WO2017055115A1

WO2017055115A1 - Lighting module and lighting device comprising the lighting module.

Info

Publication number: WO2017055115A1
Application number: PCT/EP2016/072093
Authority: WO
Inventors: Peter Johannes Martinus BUKKEMS; Adrianus Johannes Stephanus Maria De Vaan
Original assignee: Philips Lighting Holding B.V.
Priority date: 2015-10-02
Filing date: 2016-09-19
Publication date: 2017-04-06

Abstract

A lighting module (10) is disclosed, which is mountable in a lighting device (20). The lighting module (10) comprises a carrier substrate (14) including an at least in part flexible sheet assembly (12). At least a portion of the sheet assembly (12) is arranged in a rolled-up arrangement that has been rolled more than one turn so as to form a layered structure. The layered structure may comprise a tubular member (13), having a tubular shape. The layered structure is arranged such that, at least when the lighting module (10) is mounted in the lighting device (20), there is at least one intervening space (17) between at least two adjacent, opposing surfaces of the at least a portion of the sheet assembly (12), wherein the intervening space (17) permits passage of fluid through the layered structure or tubular member (13) by the fluid passing between the at least two adjacent, opposing surfaces. The at least one light-emitting element (11) may be coupled to the sheet assembly (12). A lighting device (20) comprising a lighting module (10) and a method of manufacturing a lighting device (20) are also disclosed.

Description

Lighting module and lighting device comprising the lighting module

TECHNICAL FIELD

The present invention generally relates to the field of lighting devices.

Specifically, the present invention relates to a lighting module that is configured to be arranged or mounted within an at least in part light-transmissive envelope. The present invention further relates to a lighting device comprising such a lighting module.

BACKGROUND

The use of solid state lighting devices, such as light-emitting diodes (LEDs), for illumination purposes continues to attract attention. Compared to incandescent lamps, fluorescent lamps, gas discharge lamps, etc., solid state based light sources may provide numerous advantages such as, inter alia, longer operational life, reduced power consumption, higher efficacy, less heat generation, green environmental products (i.e. not including mercury). Efforts have been made in order to develop solid state based lighting devices mimic or resemble traditional incandescent lighting devices, e.g. with respect to light distribution, correlated color temperature and/or the mechanical envelope. Since there are many luminaires developed to contain the traditional lighting devices such as, e.g., incandescent lamps, LED based 'retrofit lamps' are desired, which retrofit lamps are designed to have the appearance of a traditional incandescent light bulb and to be mounted in a conventional luminaire socket, etc. A particularly interesting direction is LED based lighting devices that are built in a glass bulb like an incandescent lamp, where the light emitting filament wire is replaced with one or more LEDs. This is particularly interesting since a huge manufacturing base is installed to manufacture the glass envelopes of such lamps at very low cost. Cooling of the LEDs in such LED based retrofit lamps may however pose a problem. Overheating of LEDs can lead to reduced lifetime, decreased light output or failure of the LEDs. Overheating of other components of the LED lamps, such as for example driver circuitry for driving LED(s) that is/are included in the LED lamp, may also be detrimental to the functionality and/or capacity of the LED lamp. US8791640B2 discloses a lamp using LEDs, which according to US8791640B2 requires relatively little cooling. However, there is still need in the art for increasing the efficiency in removing heat from such lighting devices.

SUMMARY

In view of the above, a concern of the present invention is to provide a lighting module or lighting device which allows for achieving a relatively high heat flow from the light-generating element(s) and other components such as the driver electronics and/or the control electronics, or from the lighting module or lighting device itself, towards the bulb environment (i.e. the outer surface of the bulb).

Another concern of the present invention is to enable the assembling of such retrofit lighting devices in a similar way as for inter alia incandescent lighting devices, such that already available manufacturing equipment may be re-used.

To address at least one of these concerns a lighting module and a method of manufacturing a lighting device in accordance with the independent claims are provided. Preferred embodiments are defined by the dependent claims.

According to a first aspect there is provided a lighting module. The lighting module is mountable in a lighting device. The lighting module comprises at least one carrier substrate configured to support at least one light-emitting element. The carrier substrate includes an at least in part flexible sheet assembly, wherein at least a portion of the sheet assembly is arranged in a rolled-up arrangement that has been rolled more than one turn so as to form a layered structure, and wherein the layered structure is arranged such that, at least when the lighting module has been mounted in the lighting device, there is at least one intervening space between at least two adjacent, opposing surfaces of the at least a portion of the sheet assembly. The intervening space permits passage of fluid through the layered structure by the fluid passing between the at least two adjacent, opposing surfaces of the at least a portion of the sheet assembly.

The at least one light-emitting element may be mechanically and electrically coupled to the sheet assembly.

For example, the lighting module may be mountable, or configured to be mounted, within an at least in part light-transmissive envelope of a lighting device. The layered structure may be arranged such that, at least when the lighting module has been mounted within the at least in part light-transmissive envelope, there is at least one intervening space between at least two adjacent, opposing surfaces of the at least a portion of the sheet assembly. By way of the intervening space between at least two adjacent, opposing surfaces of the at least a portion of the sheet assembly, which intervening space permits passage of fluid (such as, for example, air, nitrogen, oxygen, hydrogen, helium, or a gas composition including or containing at least one of these gas elements) through the layered structure by the fluid passing between the at least two adjacent, opposing surfaces of the at least a portion of the sheet assembly, the at least a portion of the sheet assembly that is arranged in a rolled-up arrangement may provide functionality similar to that of a chimney, allowing for the fluid to flow through the layered structure, thereby facilitating heat transport by way of convection within the layered structure for cooling of the layered structure and the at least one light-emitting element. Thereby, a relatively high degree of cooling of light- emitting element(s) and possibly other components which may be coupled to the sheet assembly may be achieved.

The at least a portion of the sheet assembly may be arranged in a rolled-up arrangement that has been rolled an integer number of full or complete turns and possibly additionally a part of a full or complete turn. For example, the at least a portion of the sheet assembly may be arranged in a rolled-up arrangement that has been rolled one and a half turns, or two and a half turns, etc.

The at least a portion of the sheet assembly may for example be arranged in a rolled-up arrangement that has been rolled more than one turn so as to form a tubular member which exhibits a layered structure. Thus, the layered structure may have a tubular shape.

As mentioned in the foregoing, at least a portion of the sheet assembly is arranged in a rolled-up arrangement that has been rolled more than one turn so as to form a layered structure, or a tubular member exhibiting a layered structure. According to one or more embodiments of the present invention, a portion of the sheet assembly is arranged in a rolled-up arrangement that has been rolled more than one turn so as to form a layered structure, which portion may carry or support the at least one light-emitting element, while another portion or portions of the sheet assembly may be arranged in a rolled-up arrangement that has been rolled less than one turn. The latter portion or portions may for example carry or support for example driver electronics or circuitry and/or other components.

The layered structure may be arranged such that there is a plurality of intervening spaces between the at least two adjacent, opposing surfaces of the at least a portion of the sheet assembly. For example, there may be a distance between only some adjacent turns of the at least a portion of the sheet assembly. The layered structure or tubular member may hence have layers not all of which are in contact with each other. The layers, or at least some of the layers, may be arranged with an intervening space there between, at least when the lighting module is mounted within the at least in part light-transmissive envelope. The intervening space may for example comprise or be constituted by an open void or cavity.

According to one or more embodiments of the present invention, the layered structure or tubular member may be hollow, for example similarly to a tube or conduit. The layered structure or tubular member may include a region or cavity defined (at least in part) by the innermost turn of the at least a portion of the sheet assembly (at least when the lighting module is mounted within the at least in part light-transmissive envelope) which for example may include or be constituted by open void(s), permitting any fluid, such as, for example, air, nitrogen, oxygen, hydrogen, helium, or a gas composition including or containing at least one of these gas elements, to pass through the layered structure or tubular member. Thereby, it may be further facilitated to transport heat by way of convection taking place within the layered structure or tubular member for cooling of the layered structure or tubular member and the at least one light-emitting element.

According to one or more embodiments of the present invention, in case there is a plurality of intervening spaces within the layered structure, at least some of the intervening spaces may have different size.

The spacing or distance between two adjacent turns or adjacent, opposing surfaces of the sheet assembly may differ from (i.e. be larger or smaller) the spacing or distance between two other adjacent turns or adjacent, opposing surfaces of the sheet assembly. Another way to describe this is that the distance between any adjacent, spaced turns or adjacent, opposing surfaces of the at least a portion of the sheet assembly may vary, or be the same or substantially the same.

As indicated in the forgoing, the intervening space(s) may for example comprise or be constituted by one or more open voids or cavities. However, it is to be understood that some filler material, which for example may be a porous material that allows for a fluid flow there through, may possibly be arranged in at least a part of the intervening space, or, in case there is a plurality of intervening spaces within the layered structure, in at least a part of at least one of the plurality of intervening spaces.

In order to fixate the shape of the at least a portion of the sheet assembly, edges of the sheet assembly at one or both end portions of the layered structure or tubular member may for example be partially glued, welded, clamped, pressed or fastened together. According to another example, the shape of the at least a portion of the sheet assembly may be fixated for example by arranging supports such as clips or the like at one or both end portions of the layered structure or tubular member. In alternative or in addition, the edges of the at least a portion of the sheet assembly may be appropriately shaped to allow proper fixation of the at least a portion of the sheet assembly in the lighting module or lighting device. In order to fixate the shape of the at least a portion of the sheet assembly, the edges of the at least a portion of the sheet assembly may be shaped. The edges of the at least a portion of the sheet assembly may for example be shaped so as to exhibit a hook-like arrangement, which may allow for it to relatively easily be clipped or mounted in the lighting module or lighting device.

As will be discussed further in the following, a lighting module according to the first aspect may be included in a lighting device comprising a light-transmissive envelope, which may at least in part enclose the lighting module and in which the lighting module may be mounted. The light-transmissive envelope may at least in part define a fluidly sealed and enclosed space within which the lighting module is arranged, and which enclosed space may include or be filled with a thermally conductive fluid, for example a gas such as air, nitrogen, oxygen, hydrogen, helium, or a gas composition containing at least one of these gas elements. The lighting device may for example be included in or constitute a LED bulb or retrofit lamp which is connectable to a lamp or luminaire socket by way of some appropriate connector, for example an Edison screw base, a bayonet fitting, or another type of connection suitable for the lamp or luminaire known in the art.

The light-transmissive envelope may comprise a through-hole for mounting and/or insertion of the lighting module within the light-transmissive envelope.

The rolled-up arrangement may be arranged such that the at least a portion of the sheet assembly has been rolled more than one turn into a releasably fixed arrangement, such that the at least a portion of the sheet assembly by the rolling experiences an elastic compressive force along at least one length dimension of the layered structure or tubular member. The elastic compressive force may cause the at least a portion of the sheet assembly to become compressed so as to permit insertion of at least the sheet assembly, or the entire or substantially the entire carrier substrate, within the light-transmissive envelope through the through-hole.

In the context of the present application, by the at least a portion of the sheet assembly being "compressed so as to permit insertion" of the carrier substrate or the sheet assembly within the light-transmissive envelope through the through-hole, it is meant that the at least a portion of the sheet assembly may be compressed so as to attain such a small size, e.g. such a small diameter, so as to permit the carrier substrate or the sheet assembly to fit through the through-hole for insertion within the light-transmissive envelope. After the carrier substrate or the sheet assembly has been inserted and possibly mounted within the light-transmissive envelope, the roll can be released from releasably fixed arrangement so as to form a larger roll or tube inside the light-transmissive envelope (as compared to when being in the releasably fixed arrangement), which roll or tube may have a larger diameter than the through-hole or entrance opening of the light-transmissive envelope, and which roll or tube may consist of only a single layer of the flexible sheet assembly. Alternatively, the roll or tube may be released to form a non-tubular sheet assembly inside the light- transmissive envelope.

Alternatively, the roll may consist of a single layer of carrier material which, after released, expands to such a form factor that it may not pass anymore the through-hole for insertion within the light-transmissive envelope.

By means of the sheet assembly being at least in part flexible, at least a portion of the sheet assembly may hence be rolled more than one turn such that it experiences an elastic compressive force that may cause the at least a portion of the sheet assembly to become compressed. This may be comparable to rolling up a sheet of a material such as paper or the like into a roll that is rolled so hard, that in case the roll is released by the person who rolled the sheet, the roll expands diametrically due to its own elastic force, possibly so as to increase the spacing between at least some of the turns of the roll.

According to one or more embodiments of the present invention, at least a portion of the sheet assembly may be arranged in a rolled-up arrangement that has been spirally rolled more than one turn. According to one or more other embodiments of the present invention, at least a portion of the sheet assembly may be arranged in a rolled-up arrangement that has been perpendicularly rolled more than one turn. For example, the at least a portion of the sheet assembly may be arranged in a rolled-up arrangement that has been rolled more than one turn such that the layered structure or tubular member exhibits a conical, or substantially conical, shape, or a cylindrical, or substantially cylindrical, shape, or a bar shape. In the context of the present application, by the layered structure or tubular member being substantially conical or substantially cylindrical it is meant that the layered structure or tubular member may be cone-like or cylinder-like, respectively, i.e. having a shape or form at least in part resembling the shape or form of a cone or cylinder, respectively, and not necessarily shaped as a perfect or ideal cone or cylinder, respectively. It is to be understood that in the context of the present application, by the layered structure or tubular member being conical or substantially conical, the layered structure or tubular member may be shaped similar to or in accordance with a truncated cone. In the context of the present application, by a bar shape it is meant a shape similar to or in accordance with a bar.

The carrier substrate may be configured to support driver circuitry. The driver circuitry may be electrically coupled to the at least one light-emitting element. The driver circuitry may comprise or be constituted by driver circuitry such as known in the art, which may be capable of converting electricity from mains power or another power supply to electricity suitable to operate or drive the at least one light-emitting element. The driver circuitry may be capable of at least converting between Alternating Current and Direct Current and converting voltage into a suitable voltage for operating or driving the at least one light-emitting element. The driver circuitry might incorporate control circuitry configured to control the driver circuitry. The control circuitry may be capable to receive control commands to control the driver circuitry, e.g. so as to modify settings in the driver circuitry. The control circuitry might be capable to receive control commands employing any known method, such as wireless radio frequency, infrared (IR), or ultrasonic communication. In alternative or in addition, the control circuitry or driver circuitry may be configured to receive control commands via electrical conductors connected to the driver circuitry.

The carrier substrate may be configured to support control circuitry. Thus, it is not necessary that the driver circuitry (possibly) incorporates the control circuitry. The driver circuitry and the control circuitry may hence be separately arranged.

The layered structure may be arranged such that, at least when the lighting module has been mounted in the lighting device, there is at least one layer of the at least a portion of the sheet assembly between the at least one light-emitting element and at least a portion of the driver circuitry and/or the control circuitry.

The at least one light-emitting element may be arranged on the sheet assembly so as to end up an outer surface of the layered structure (or tubular member), possibly so as to directly face a light-transmissive envelope of the lighting device when the lighting module has been mounted in the lighting device. The driver circuitry and/or the control circuitry may be arranged on the sheet assembly so as to end up on an inner surface of the layered structure (or tubular member). For example, the at least one light-emitting element may be arranged on the sheet assembly so as to end up an outer surface of the layered structure (or tubular member), and the driver circuitry and/or the control circuitry may be arranged on the sheet assembly so as to end up on an inner surface of the layered structure (or tubular member) that is facing an inner surface of the layered structure (or tubular member) opposite to the outer surface of the layered structure (or tubular member) on which the at least one light-emitting element is arranged.

The carrier substrate may include at least one radio-frequency antenna. The at least one radio-frequency antenna may for example be integrated or encapsulated in the carrier substrate. The at least one light source and/or the driver circuitry may be controllable with respect to operation thereof. For example, as known in the art, LEDs may be

controllable with respect to brightness of emitted light, and with respect to switching them on and off. The at least one light source and/or the driver circuitry may for example be configured so as to receive one or more control signals or messages, e.g. from some control unit which may be included in the lighting module or the lighting device, for controlling operation thereof. By way of the at least one radio-frequency antenna, one or more control signals or messages may be received wirelessly from some other entity capable of wireless communication. The at least one radio -frequency antenna may for example be capable of wireless communication using any communication technique or means known in the art. In principle, any appropriate telecommunication, data transmission, digital transmission, or digital communication technique may be employed.

The carrier substrate may for example include at least one flexible printed circuit board (PCB) and/or flexible foil. The flexible PCB and/or the flexible foil may constitute or be included in the sheet assembly. By the sheet assembly being constituted by or including a flexible PCB and/or a flexible foil and by the rolled-up arrangement of the at least a portion of the sheet assembly, the number of required conductors, connections, wiring, etc., for connecting light-emitting element(s), driver circuitry, radio -frequency antenna(s), and/or other electrical components may become relatively low, since every one or substantially all of such components may be arranged on a single carrier substrate, instead of requiring several carrier substrates for connecting different components.

The carrier substrate may be configured to transfer heat, generated for example by driver circuitry, the at least one radio -frequency antenna and/or the at least one light- emitting element when in use, away from the driver circuitry, the at least one radio-frequency antenna and/or the at least one light-emitting element. Thus, the carrier substrate may be configured so as to exhibit a heat transferring capacity and/or functionality.

The carrier substrate may comprise or consist of a stack of layers of materials, wherein one layer in the stack may form the electrical interfaces between any electronic components. The carrier substrate may comprise or consist of a stack of layers of materials, wherein one layer in the stack may form a thermal path to allow heat flow from any electronic components and to spread this heat towards a relatively large surface area, thereby allowing the heat to flow via the gas within the light-transmissive envelope towards the outer surface of the light-transmissive envelope.

The material forming the thermal path within the carrier substrate preferably comprises a material having a relatively high thermal conductivity, such as, for example, copper or aluminum.

The material forming the electrical paths within the carrier substrate preferably comprises a material having a relatively high electrical conductivity, such as, for example, copper, aluminum, silver, gold, carbon, graphene, steel, iron, zinc, nickel, tin, or any kind of solder alloy.

The carrier substrate may comprise a relatively thin, flexible PCB material, including electrically conductive tracks or paths, e.g. comprising copper, forming the electrical interfaces between any electrical components.

The carrier substrate may comprise a relatively thin, flexible substrate, such as a thin polymer film, where the conductors forming the electrical interfaces between electrical components are printed on the polymer film.

The carrier substrate may comprise a relatively thin, flexible substrate, such as a thin film of a highly thermal conductive material such as aluminum, copper or another metal film, where the conductors forming the electrical interfaces between electrical components are printed on the metal film, having an insulator layer between the printed conductors and the metal film.

The electrical components may be electrically connected to the conductive paths on the carrier substrate by an electrical conductive adhesive or (preferably) by means of soldering.

The electrical paths on the flexible substrate preferably comprise copper, aluminum or silver paths. The electrical paths may be printed on the flexible substrate by the printing and curing of an electrical conductive ink, such as an electrical conductive ink based on copper particles, silver particles, aluminum particles, or any combination thereof.

The electrical paths on the flexible substrate may consist of a stack of two or more electrically conductive layers, such as tracks of a first material A providing good adhesion on the carrying substrate, tracks of a second material B providing good adhesion to the first material A providing highly electrical conductive paths, tracks of a third material C providing good adhesion on the second material B and enabling an electrical solder joint connection between the electrical components and the second material B.

The electrical paths on the flexible substrate may comprise a relatively large and thick copper pattern, allowing heat generated by the electronic components when in use to flow over, and spread over, a relatively large part or portion of the flexible substrate.

The electrical components are preferably soldered to the electrical conductive paths on the flexible substrate, such that the heat may flow from the electrical components via the solder connections towards the flexible substrate and such that the electrical components can be assembled on the flexible substrates using conventional pick and place and solder technologies.

The rolled-up arrangement of the sheet assembly may be formed starting from the sheet assembly being in a flat or substantially flat state. The carrier substrate of the lighting module may for example be formed starting from a portion of a relatively large carrier substrate or sheet assembly which may possibly be in a flat or substantially flat state. For example, the carrier substrate of the lighting module may for example be cut from such a relatively large carrier substrate or sheet assembly. Light-emitting elements and possibly other electrical components may be coupled to the relatively large carrier substrate or sheet assembly prior to forming the carrier substrate of the lighting module from a portion of such a relatively large carrier substrate or sheet assembly. Several carrier substrates of lighting modules according to embodiments of the present invention may be formed from a single one of such a relatively large carrier substrate or sheet assembly.

The at least one light-emitting element may be arranged on the sheet assembly so as to end up an outer surface and/or possibly an inner surface of the layered structure or tubular member.

The at least one light-emitting element may for example include or be constituted by a solid state light emitter. Examples of solid state light emitters include inorganic LEDs, organic LEDs, laser diodes and light conversion elements such as phosphor plates, Lumiramic plates or phosphor conversion crystals. Solid state light emitters are relatively cost efficient light sources, since they in general are relatively inexpensive to manufacture, have a relatively high optical efficiency, have a relatively long lifetime and are environmentally friendly. However, in the context of the present application, the term "light- emitting element" should be understood to mean substantially any device or element that is capable of emitting radiation in any region or combination of regions of the electromagnetic spectrum, for example the visible region, the infrared region, and/or the ultraviolet region, when activated e.g. by applying a potential difference across it, passing a current through it or illuminating it with light of particular wavelengths. Therefore a light-emitting element can have monochromatic, quasi-monochromatic, polychromatic or broadband spectral emission characteristics. Examples of light-emitting elements include semiconductor, organic, or polymer/polymeric LEDs, violet LEDs, blue LEDs, Red LEDs, Green LEDs, Amber LEDs, UV-A LEDs, UV-B LEDs, UV-C LEDs, optically pumped phosphor coated LEDs, optically pumped nano-crystal LEDs, lasers, laser pumped phosphor, laser pumped nano-crystals, optically pumped light conversion elements or any other similar devices as would be readily understood by a person skilled in the art. Furthermore, the term light-emitting element can, according to one or more embodiments of the present invention, mean a combination of the specific light-emitting element or light-emitting elements which emit the radiation in combination with a housing or package within which the specific light-emitting element or light-emitting elements are positioned or arranged. For example, the term light-emitting element can encompass a bare LED die arranged in a housing, which may be referred to as a LED package.

According to a second aspect there is provided a lighting device comprising a lighting module according to the first aspect.

The lighting device may comprise comprising an at least in part light- transmissive envelope, within which the lighting module may be mountable. The lighting module may be mounted within the light-transmissive envelope. The light-transmissive envelope may for example be transparent or translucent, or it may include at least one portion that is transparent and at least one portion that is translucent. The light-transmissive envelope may for example be made of, at least in part, glass, for example fused silica glass (vitreous silica glass), soda-lime-silica glass (window glass), sodium borosilicate glass (pyrex), lead- oxide glass (crystal glass), aluminosilicate glass, or oxide glass. In alternative or in addition, the light-transmissive envelope may be made of, at least in part, sapphire and/or or transparent or translucent ceramic. The light-transmissive envelope may in principle have any shape. According to examples, the light-transmissive envelope may be spherical-shaped, pear-shaped or tube-shaped. The light-transmissive envelope may have any shape as known for conventional lamps.

The light-transmissive envelope may comprise at least one light-scattering element configured to scatter light incident on the at least one light-scattering element. By means of the at least one light-scattering element, light output from the lighting module or lighting device may become more homogeneous. Light-scattering effects may be desired for aesthetical purposes (e.g. so as to provide a sparkling effect to a viewer). For example, the at least one light-scattering element may comprise light-scattering particles embedded or integrated in the light-transmissive envelope. The at least one light-scattering element may for example be positioned between the at least one light-emitting element and the light- transmissive envelope. In alternative or in addition, the at least one light-scattering element may comprise a layer or coating of material such as A1203, BaS04 and/or Ti02 on an inner and/or outer surface of the light-transmissive envelope, and/or an inner and/or outer surface of the light-transmissive envelope may be made diffusing, e.g. so as to exhibit a rough structure.

The light-scattering elements may consist of optical surface structures, intended to scatter the light and/or to direct the light in any preferred directions.

According to a third aspect there is provided a method of manufacturing a lighting device comprising a lighting module mounted within a light-transmissive envelope, the lighting module comprising at least one carrier substrate configured to support at least one light-emitting element, wherein the carrier substrate comprises an at least in part flexible sheet assembly. The method comprises arranging at least a portion of the sheet assembly in a rolled-up arrangement, by rolling the at least a portion of the sheet assembly more than one turn so as to form a layered structure. The sheet assembly is mounted within the light- transmissive envelope. The rolling of the at least a portion of the sheet assembly a plurality of more than one turn is such that the layered structure is or becomes arranged such that, at least when the lighting module is mounted within the at least in part light-transmissive envelope, there is at least one intervening space between at least two adjacent, opposing surfaces of the at least a portion of the sheet assembly. The intervening space permits passage of fluid through the layered structure by the fluid passing between the at least two adjacent, opposing surfaces.

The method may comprise mechanically and electrically coupling the at least one light-emitting element to the sheet assembly.

The light-transmissive envelope may comprise a through-hole.

The at least a portion of the sheet assembly may be rolled more than one turn into a releasably fixed arrangement such that the at least a portion of the sheet assembly by the rolling experiences an elastic compressive force along at least one length dimension of the layered structure or tubular member, wherein the elastic compressive force causes the at least a portion of the sheet assembly to become compressed so as to attain a size that permits insertion of at least the sheet assembly, or the entire or substantially the entire carrier substrate, within the light-transmissive envelope through the through-hole. The at least a portion of the sheet assembly may be (e.g. temporarily or momentarily) held in the releasably fixed arrangement. At least the sheet assembly may then be inserted within the light- transmissive envelope through the through-hole.

In the context of the present application, by the at least a portion of the sheet assembly becoming compressed so as to attain a size that permits insertion of at least the sheet assembly, or the entire or substantially the entire carrier substrate, within the light- transmissive envelope through the through-hole, it is meant that the at least a portion of the sheet assembly attains a size such that it is possible to insert at least the sheet assembly within the light-transmissive envelope through the through-hole, without or substantially without risking to damage the sheet assembly while passing it through the through-hole (that is to say, so as to not have to force the sheet assembly through the through-hole). Once the 'spring rolled' sheet assembly has been inserted within the light-transmissive envelope through the through-hole, it may then 'spring back' such that its size becomes larger.

For example, after having inserted at least the sheet assembly within the light- transmissive envelope, the at least a portion of the sheet assembly may be released from the releasably fixed arrangement. That is to say, the at least a portion of the sheet assembly may be released so that the at least a portion of the sheet assembly is not in the releasably fixed arrangement, and such that the elastic compressive force along at least one length dimension of the layered structure or tubular member vanishes entirely or in part. Thereby, the layered structure or tubular member may expand (that is, for example when being within the light- transmissive envelope) along the at least one length dimension of the layered structure or tubular member. The expansion of the layered structure or tubular member may be based on at least a part of the elastic compressive force that is released. For example, the expansion of the layered structure or tubular member may be based on the magnitude of the at least part of the elastic compressive force. The elastic compressive force may be such so as to, when the at least a portion of the sheet assembly is released from the releasably fixed arrangement, cause the layered structure to expand along the at least one length dimension of the layered structure such that the at least a portion of the sheet assembly attains a size that does not permit withdrawing at least the sheet assembly from the light-transmissive envelope through the through-hole. For example in case the layered structure or tubular member is cylindrical or has a cylinder-like shape, the expansion of the layered structure or tubular member may be radially, e.g., such that a radius of the layered structure or tubular member becomes larger. Thus, the at least one length dimension of the layered structure or tubular member may for example be a radius of the layered structure or tubular member.

For example in case the layered structure or tubular member is conical or has a cone-like shape (possibly according to the shape of a truncated cone), the expansion of the layered structure or tubular member may be radially with respect to a base radius of the layered structure or tubular member, e.g., such that a base radius of the layered structure or tubular member becomes larger. Thus, the at least one length dimension of the layered structure or tubular member may for example be a base radius of the layered structure or tubular member.

According to one or more embodiments of the present invention, the intervening space or intervening spaces within the layered structure may be enlarged or even formed by way of the expansion of the layered structure or tubular member. This may facilitate a relatively large flow of fluid through the layered structure or tubular member, whereby a relatively high thermal flow by convection within the layered structure or tubular member may be achieved.

The arranging of the at least a portion of the sheet assembly in a rolled-up arrangement by rolling the at least a portion of the sheet assembly more than one turn so as to form a layered structure may for example comprise spirally rolling the at least a portion of the sheet assembly more than one turn.

Further objects and advantages of the present invention are described in the following by means of exemplifying embodiments. It is noted that the present invention relates to all possible combinations of features recited in the claims. Further features of, and advantages with, the present invention will become apparent when studying the appended claims and the description herein. Those skilled in the art realize that different features of the present invention can be combined to create embodiments other than those described herein.

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplifying embodiments of the invention will be described below with reference to the accompanying drawings.

Fig. 1 is a schematic side view of a lighting device according to an embodiment of the present invention. Fig. 2 is a schematic view from the above of a carrier substrate including an at least in part flexible sheet assembly in accordance with an embodiment of the present invention, wherein at least a portion of the sheet assembly can be arranged in a rolled-up arrangement that has been rolled more than one turn so as to form a tubular member exhibiting a layered structure.

Fig. 3 is a schematic side view of a carrier substrate including an at least in part flexible sheet assembly in accordance with an embodiment of the present invention, wherein the sheet assembly is arranged in a rolled-up arrangement that has been rolled more than one turn so as to form a tubular member exhibiting a layered structure.

Fig. 4 is a schematic view from the above of a carrier substrate including an at least in part flexible sheet assembly in accordance with an embodiment of the present invention, wherein the sheet assembly is arranged in a rolled-up arrangement that has been rolled more than one turn so as to form a tubular member exhibiting a layered structure.

Fig. 5 is a schematic side view of a carrier substrate including an at least in part flexible sheet assembly in accordance with an embodiment of the present invention, wherein the sheet assembly is arranged in a rolled-up arrangement that has been rolled more than one turn so as to form a tubular member exhibiting a layered structure.

Fig. 6 is a schematic side view of a lighting device according to an embodiment of the present invention that is in a partly assembled state, and wherein the sheet assembly has been rolled more than one turn into an intermediate, releasably fixed arrangement.

Fig. 7 is a schematic side view of the lighting device illustrated in Figure 6, wherein the sheet assembly, which has been rolled more than one turn into an intermediate, releasably fixed arrangement, has been inserted within the light-transmissive envelope.

Fig. 8 is a schematic side view of the lighting device illustrated in Figures 6 and 7, wherein the sheet assembly has been released from the intermediate, releasably fixed arrangement.

Fig. 9 is a schematic flowchart illustrating a method of manufacturing a lighting device according to an embodiment of the present invention.

All the figures are schematic, not necessarily to scale, and generally only show parts which are necessary in order to elucidate embodiments of the present invention, wherein other parts may be omitted or merely suggested. DETAILED DESCRIPTION

The present invention will now be described hereinafter with reference to the accompanying drawings, in which exemplifying embodiments of the present invention are shown. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments of the present invention set forth herein; rather, these embodiments of the present invention are provided by way of example so that this disclosure will convey the scope of the invention to those skilled in the art. In the drawings, identical reference numerals denote the same or similar components having a same or similar function, unless specifically stated otherwise.

Figure 1 is a schematic side view of a lighting device 20 according to an embodiment of the present invention. The lighting device 20 comprises an at least in part light-transmissive envelope 2 and a lighting module 10 that is mounted within the light- transmissive envelope 2.

The light-transmissive envelope 2 may for example be transparent or translucent, or it may include at least one portion that is transparent and at least one portion that is translucent. The light-transmissive envelope 2 for example be made of, at least in part, glass, for example fused silica glass, soda-lime-silica glass, sodium borosilicate glass, lead- oxide glass, alumino silicate glass, or oxide glass. It is to be understood that the shape of the light-transmissive envelope 2 depicted in Figure 1 is according to an example, and that, according to one or more other embodiments of the present invention, other shapes of the light-transmissive envelope 2 are possible.

It is to be understood that only a portion of the light-transmissive envelope 2 is depicted in Figure 1, in order to offer a more clear view of the lighting module 10 that is mounted within the light-transmissive envelope 2.

Further in accordance with the embodiment of the present invention illustrated in Figure 1 , the lighting device 20 may comprise a base 3 for connection to a lamp or luminaire socket (not shown in Figure 1). The base 3 may include or be constituted by any suitable type of coupler or connector, for example an Edison screw base, a bayonet fitting, or any other type of connection which may be suitable for the particular type of lamp or luminaire.

The light-transmissive envelope 2 may define a fluidly sealed and enclosed space 5 within which the lighting module 10 is arranged, and which space may include or be filled with a thermally conductive fluid, for example a gas such as air, nitrogen, oxygen, hydrogen, helium, or a gas composition containing at least one of these gas elements. For accommodating the lighting module 10 within the light-transmissive envelope 2 the light- transmissive envelope 2 may be hollow or include an open void or cavity.

The light-transmissive envelope 2 may comprise a through-hole (not shown in Figure 1) for insertion of the lighting module 10 within the light-transmissive envelope 2 (cf. the following description referring to Figures 6 to 8).

The lighting module 10 comprises a carrier substrate that is configured to support a plurality of light-emitting elements 11. In principle any number of light-emitting elements may be employed. According to one or more embodiments of the present invention, a single light-emitting element may be employed. The carrier substrate includes a flexible sheet assembly 12. As illustrated in Figure 1, the sheet assembly 12 is arranged in a rolled-up arrangement that has been rolled more than one turn so as to form a tubular member 13 exhibiting a layered structure, wherein the layered structure is arranged such that, at least when the lighting module 10 is mounted within the light-transmissive envelope 2, there is an intervening space between adjacent, opposing surfaces of the sheet assembly 12. The intervening space permits passage of fluid through the tubular member 13 by the fluid passing between the adjacent, opposing surfaces of the sheet assembly 12. Each of the light- emitting elements 11 is mechanically and electrically coupled to the sheet assembly 12. As illustrated in Figure 1 , the light-emitting elements 11 can be arranged on the sheet assembly 12 so as to end up an outer surface of the tubular member 13. In alternative or in addition, at least one light-emitting element may be arranged on an inner surface of the tubular member 13.

Further in accordance with the embodiment of the present invention illustrated in Figure 1, the lighting device 20 may comprise a support structure, for example of the type illustrated in Figure 1 and indicated at 4, which supports the lighting module 10 in the lighting device 20. In accordance with the embodiment of the present invention illustrated in Figure 1 , the support structure 4 may for example comprise a cylindrical support or the like connected to and/or supported by the base 3. The cylindrical support may extend for example along a longitudinal axis of the lighting module 10 (or tubular member 13) and into the tubular member 13 via an open end thereof. It is to be understood that the support structure 4 illustrated in Figure 1 is according to an exemplifying embodiment of the present invention, and that variations and other configurations of the support structure 4 are possible.

The support structure 4 may for example be made of, at least in part, glass. The support structure 4 may comprise a channel or conduit (not shown in Figure 1) that can be used to pump air out of the light-transmissive envelope 2 and introduce another gas, e.g. a thermally conductive fluid or gas, in the space 5. The channel or conduit of the support structure 4 may be used in order to provide power to the light-emitting elements 11 and any other electrical components of the lighting module 10, e.g. by means of one or more electrical conductors or wires which may extend from the outside of the light-transmissive envelope 2 to its inside via the channel or conduit. After having mounted the lighting module 10 on the support structure 4 so that the support structure 4 supports the lighting module 10 in the lighting device 20, the light-transmissive envelope 2 and the support structure 4 may be (possibly fixedly) coupled together. For example where the light-transmissive envelope 2 and the support structure 4 are made of, at least in part, glass, the light-transmissive envelope 2 and the support structure 4 may be thermally bonded together, e.g. by 'melting' them together, for example at the through-hole 21. Air may then be removed from the inside of the light-transmissive envelope 2, and another gas, e.g. a thermally conductive fluid or gas, may be introduced in the space 5. The support structure 4 may then be connected to the base 3 for example via a threaded (screw) connection or by means of a glue connection or the like.

In accordance with the embodiment of the present invention illustrated in

Figure 1, the carrier substrate may include a radio-frequency antenna 15. There may be more than one radio-frequency antenna 15. The radio-frequency antenna 15 may for example be integrated or encapsulated in the carrier substrate, or in the sheet assembly 12, or coupled thereto for example in some appropriate manner as known in the art.

The rolled-up arrangement of the sheet assembly 12 may be formed starting from the sheet assembly 12 being in a flat or substantially flat state, as illustrated in Figure 2, which is a schematic view from the above of a carrier substrate 14 including a flexible sheet assembly 12 according to an embodiment of the present invention.

As illustrated in Figure 2, there may be a plurality of light-emitting elements 11 mechanically and electrically coupled to one side of the sheet assembly 12.

It is to be understood that the number of light-emitting elements 11 and the arrangement or localization of the light-emitting elements 11 on the sheet assembly 12 as depicted in Figures 1 and 2 are according to exemplifying embodiments of the present invention and that variations are possible.

As indicated by Figure 2, the light-emitting element(s) 11 may be mechanically and electrically coupled to (e.g., one side) of the sheet assembly 12 prior to that the sheet assembly 12 is arranged in a rolled-up arrangement that has been rolled more than one turn so as to form a tubular member 13 exhibiting a layered structure, for example such as illustrated in Figure 1. In accordance with the embodiment of the present invention illustrated in Figure 2, the carrier substrate 14 may include a radio -frequency antenna 15. There may be more than one radio-frequency antenna 15. The radio-frequency antenna 15 may for example be integrated or encapsulated in the carrier substrate 14, or in the sheet assembly 12, or coupled thereto in some appropriate manner as known in the art.

Further in accordance with the embodiment of the present invention illustrated in Figure 2, the carrier substrate 14 may be configured to support driver circuitry, which is very schematically indicated at 16. As indicated in Figure 2, the driver circuitry 16 may be coupled to the sheet assembly 12. The driver circuitry 16 may be electrically coupled to the light-emitting elements 11. The driver circuitry 16 may have control circuitry incorporated, which control circuitry by way of an antenna, e.g. the radio -frequency antenna 15, may wirelessly receive control signals. The control signals may for example be transmitted from a control module or control device (not shown in Figure 2).

As indicated in Figures 1 and 2, the driver circuitry 16 may be arranged in the intervening space formed between adjacent, opposing surfaces of the sheet assembly 12.

The carrier substrate 14 may for example include at least one flexible printed circuit board (PCB) and/or flexible foil or the like, which flexible PCB and/or flexible foil may constitute or be included in the sheet assembly 12, in accordance with the embodiment of the present invention illustrated in Figures 1 and 2.

The flexible PCB may be manufactured in a traditional way, by etching a desired pattern of copper conductors from a copper layer on a top surface of the PCB substrate material or, alternatively, the flexible PCB may be manufactured using printed electronics technologies where the desired pattern of conductors is printed and cured on top of a sheet of carrier material. Alternatively, the flexible PCB may be manufactured in another appropriate way as known in the art.

The driver circuitry 16 may be electrically coupled to the light-emitting elements 11 for example by way of the sheet assembly 12 being constituted by or including a flexible PCB and/or a flexible foil, with the driver circuitry 16 and the light-emitting elements 11 being coupled to the sheet assembly 12. Also, other components which may be coupled to the sheet assembly 12 such as the radio-frequency antenna 15 may be electrically coupled to the light-emitting elements 11 and/or the driver/control circuitry 16 by way of the sheet assembly 12 being constituted by or including a flexible PCB and/or a flexible foil or the like. The driver circuitry 16 may for example include circuitry capable of converting electricity from mains power or an external power supply (not shown in Figure 1 or 2) to electricity suitable to operate or drive the light-emitting elements 11 and/or power any other electrical components that may be included in the lighting device 20. The driver circuitry 16 may be capable of at least converting between Alternating Current and Direct Current and converting voltage into a suitable voltage for operating or driving the light- emitting elements 11. The driver circuitry 16 may include other electronics such as a controller (not shown in Figure 1 or 2).

The lighting device 20 may include electronics such as wiring (not shown in Figure 1 or 2) for conveying electricity to the light-emitting elements 11, which wiring for example may extend from the base 3 to the carrier substrate 14 or the sheet assembly 12.

Figure 3 is a schematic side view of a carrier substrate including a flexible sheet assembly 12 in accordance with an embodiment of the present invention, which may be included in a lighting module according to an embodiment of the present invention. The carrier substrate illustrated in Figure 3 is similar to the carrier substrate illustrated in Figure 1. The carrier substrate is configured to support a plurality of light-emitting elements (not shown in Figure 3). As illustrated in Figure 3, the sheet assembly 12 is arranged in a rolled- up arrangement that has been rolled more than one turn so as to form a tubular member 13 exhibiting a layered structure, wherein the layered structure is arranged such that there is an intervening space between adjacent, opposing surfaces of the sheet assembly 12. The intervening space permits passage of fluid through the tubular member 13 by the fluid passing between the adjacent, opposing surfaces. According to the embodiment of the present invention illustrated in Figure 3, the sheet assembly 12 is arranged in a rolled-up arrangement that has been perpendicularly rolled more than one turn such that the tubular member 13 exhibits a cylindrical shape. However, other shapes of the tubular member 13 are possible.

With further reference to Figure 3, the sheet assembly 12 may in the rolled-up arrangement be bent, for example along bending lines on the sheet assembly 12, which bending lines for example may be parallel or substantially parallel with a longitudinal axis of the lighting module 10, tubular structure 13 or layered structure. For example, the sheet assembly 12 may in the rolled-up arrangement be bent such that the upper and/or lower base of the tubular structure 13 or layered structure may have a polygonal shape, such as for example, but not limited to, a hexagonal shape or an octagonal shape. Such a configuration of the sheet assembly 12 can be implemented in any of the other embodiments of the present invention described herein. As illustrated in Figure 3, the spacing or distance between two adjacent turns or adjacent, opposing surfaces of the sheet assembly 12 may be equal or substantially equal.

It is to be understood that according to one or more other embodiments of the present invention, the spacing or distance between two adjacent turns or adjacent, opposing surfaces of the sheet assembly 12 may be different. Such an embodiment of the present invention is illustrated in Figure 4, which is a schematic view from above of a carrier substrate including a flexible sheet assembly 12. The carrier substrate illustrated in Figure 4 is similar to the carrier substrate illustrated in Figure 3, but differs in that the spacing or distance between adjacent turns or adjacent, opposing surfaces of the sheet assembly 12 are not all the same. As illustrated in Figure 4, the spacing or distance between the adjacent turns or adjacent, opposing surfaces of the sheet assembly 12 forms an intervening space 17. For example, the spacing or distance between adjacent turns or adjacent, opposing surfaces of the sheet assembly 12 that are not at or close to an inner surface or an outer surface of the tubular member 13 may be larger than the spacing or distance between adjacent turns or adjacent, opposing surfaces of the sheet assembly 12 that are at or close to the inner surface or the outer surface of the tubular member 13.

It is to be understood that the number of turns of the rolled-up arrangement of the sheet assembly 12 illustrated in the figures is according to exemplifying embodiments of the present invention, and that variations are possible.

As mentioned in the foregoing description referring to Figure 3, other shapes of the tubular member 13 than the one illustrated in Figure 3 are possible. For example, the tubular member 13 may have a conical shape, or a shape similar to that of a truncated cone. Such a case is illustrated in Figure 5, which is a schematic side view of a carrier substrate including a flexible sheet assembly 12 in accordance with an embodiment of the present invention, which may be included in a lighting module according to an embodiment of the present invention. According to the embodiment of the present invention illustrated in Figure 5, the tubular member 13 has a shape in accordance with a truncated cone. In order to achieve a tubular member 13 having a conical shape or a shape similar to that of a truncated cone, the sheet assembly 12 (or at least a portion thereof) may be arranged in a rolled-up arrangement that has been spirally rolled more than one turn. By a tubular member 13 having a conical shape or a shape similar to that of a truncated cone, the optical axis of any light-emitting element arranged on an outer surface (or inner surface) of the tubular member 13 may be arranged non-perpendicular with respect to a longitudinal axis (not shown in Figure 5) of the tubular member 13. Thereby, it may be facilitated or enabled to provide a relatively high uniformity in light emission, e.g., with respect to light intensity and/or brightness, substantially all around the lighting module 10. That is, it may be facilitated or enabled to achieve a lighting module 10 capable of emitting light in a relatively large number of directions from the lighting module 10, or even so as to achieve a substantially

omnidirectional light emission from the lighting module 10. A skilled person will realize that other shapes of the tubular member 13 that permits the optical axis of any light-emitting element arranged on an outer surface (or inner surface) of the tubular member 13 to be arranged non-perpendicular with respect to a longitudinal axis of the tubular member 13 are possible. For example, at least a portion of an outer surface or inner surface of the tubular member 13 may curve outwards or inwards at least longitudinally.

With further reference to Figure 5, the sheet assembly 12 may in the rolled-up arrangement be bent, for example along bending lines on the sheet assembly 12, which bending lines for example may be parallel or substantially parallel with a longitudinal axis of the lighting module 10, tubular structure 13 or layered structure. For example, the sheet assembly 12 may in the rolled-up arrangement be bent such that the upper and/or lower base of the tubular structure 13 or layered structure may have a polygonal shape, such as for example, but not limited to, a hexagonal shape or an octagonal shape. Such a configuration of the sheet assembly 12 can be implemented in any of the other embodiments of the present invention described herein.

Figure 6 is a schematic side view of a lighting device 20 according to an embodiment of the present invention that is in a partly assembled state. The lighting device 20 illustrated in Figure 6 is similar to the lighting device 20 illustrated in Figure 1 , and the same reference numerals in Figures 1 and 6 denote similar or the same components, possibly with the same or similar functions or functionality. The lighting device 20 illustrated in Figure 6 differs from the lighting device 20 illustrated in Figure 1 in that the lighting module 10 includes a carrier substrate similar to that illustrated in Figure 5.

As illustrated in Figure 6, the light-transmissive envelope 2 may comprise a through-hole 21 for insertion of the lighting module within the light-transmissive envelope 2. The through-hole 21 has a diameter dl . Figure 6 illustrates a state wherein the sheet assembly 12 has been rolled more than one turn into a releasably fixed arrangement, such that the sheet assembly 12 by the rolling experiences an elastic compressive force along at least one length dimension of the tubular member 13, wherein the elastic compressive force causes the sheet assembly 12 to become compressed so as to attain a size that permits insertion of at least the sheet assembly 12, or the carrier substrate or the entire lighting module 10, within the light- transmissive envelope 2 through the through-hole 21. The sheet assembly 12 may be (e.g. temporarily or momentarily) held in the releasably fixed arrangement illustrated in Figure 6. In the releasably fixed arrangement of the sheet assembly 12 illustrated in Figure 6, the base of the tubular member 13 has a diameter d2 that is less than dl .

Figure 7 is a schematic side view of the lighting device 20 illustrated in Figure

6, wherein the sheet assembly 12, while being held in the releasably fixed arrangement illustrated in Figure 6, has been inserted within the light-transmissive envelope 2.

In accordance with the embodiment of the present invention illustrated in Figures 6 and 7, by the sheet assembly 12 being compressed so as to permit insertion of the lighting module 10, the carrier substrate or the sheet assembly 12 within the light- transmissive envelope 2 through the through-hole 21, the sheet assembly 12 is compressed so as to attain a size that permits the lighting module 10, the carrier substrate or the sheet assembly 12 to fit through the through-hole 21 (since d2 is less than dl), so as to permit insertion of the lighting module 10, the carrier substrate or the sheet assembly 12 within the light-transmissive envelope 2.

After having inserted the lighting module 10, the carrier substrate or the sheet assembly 12 within the light-transmissive envelope 2, the sheet assembly 12 may be released from the releasably fixed arrangement, so that the sheet assembly 12 is not anymore in the releasably fixed arrangement, and such that the elastic compressive force along at least one length dimension of the tubular member 13 vanishes entirely or in part. Thereby, the tubular member 13 may expand within the light-transmissive envelope 2 along the at least one length dimension of the tubular member 13. The expansion of the tubular member 13 may be based on at least a part of the elastic compressive force that is released. For example, the expansion of the tubular member 13 may be based on the magnitude of the at least part of the elastic compressive force. Since the sheet assembly 12 is flexible, the expansion of the tubular member 13 may be due to its own elastic force.

With reference to the description in the foregoing referring to Figure 1 , the sheet assembly 12 may for example be released from the releasably fixed arrangement after having mounted the lighting module 10 on the support structure 4 so that the support structure 4 supports the lighting module 10 in the lighting device 20, and before the light- transmissive envelope 2 and the support structure 4 are coupled together.

Expansion of the tubular member 13 within the light-transmissive envelope 2 is illustrated in Figure 8, which is a schematic side view of the lighting device 20 illustrated in Figures 6 and 7, wherein the sheet assembly 12 has been released from the intermediate, releasably fixed arrangement, whereby the tubular member 13 has expanded within the light- transmissive envelope 2. The tubular member 13 may thereby expand so as to attain a size that does not permit the lighting module 10, the carrier substrate or the sheet assembly 12 to fit through the through-hole 21. In accordance with the embodiment of the present invention illustrated in Figure 8, the tubular member 13, which has a shape in accordance with a truncated cone, has expanded radially with respect to the radii of the base plane and the truncation plane of the tubular member 13, such that the radii of the base plane and the truncation plane of the tubular member 13 have become larger. In accordance with the embodiment of the present invention illustrated in Figure 8, the base of the tubular member 13 has a diameter d3, which is larger than dl .

By way of expansion of the tubular member 13 within the light-transmissive envelope 2, the intervening space or intervening spaces within the layered structure may be enlarged (for example as compared to when the sheet assembly 12 is in the releasably fixed arrangement illustrated in Figures 6 and 7) or even formed.

It is to be understood that the carrier substrates illustrated in Figures 3 to 8 may support at least one light-emitting element and possibly driver circuitry thereon, and possibly having at least one radio-frequency antenna coupled thereto, similarly to the carrier substrates illustrated in Figure 1 or 2. However, such possible components (as well as other possible components) which may be supported on or coupled to the respective carrier substrates illustrated in Figures 3 to 8 are not shown in Figures 3 to 8.

Figure 9 is a schematic flowchart illustrating a method 90 according to an embodiment of the present invention., which method 90 is for manufacturing a lighting device comprising a lighting module mounted within a light-transmissive envelope, which lighting module comprises a carrier substrate configured to support at least one light-emitting element, and which carrier substrate comprises an at least in part flexible sheet assembly.

The at least one light-emitting element may be mechanically and electrically coupled to the sheet assembly, 91.

At least a portion of the sheet assembly is arranged in a rolled-up arrangement, 92, by rolling the at least a portion of the sheet assembly more than one turn so as to form a layered structure.

The sheet assembly is mounted within the light-transmissive envelope, 93. By the arranging of the at least a portion of the sheet assembly in a rolled-up arrangement by rolling the at least a portion of the sheet assembly more than one turn so as to form a layered structure, the layered structure becomes arranged such that, at least when the lighting module is mounted within the at least in part light-transmissive envelope, there is an intervening space between at least two adjacent, opposing surfaces of the at least a portion of the sheet assembly, wherein the intervening space permits passage of fluid through the layered structure by the fluid passing between the at least two adjacent, opposing surfaces.

In conclusion it is disclosed a lighting module mountable in a lighting device.

The lighting module comprises a carrier substrate including an at least in part flexible sheet assembly. At least a portion of the sheet assembly is arranged in a rolled-up arrangement that has been rolled more than one turn so as to form a layered structure. The layered structure may comprise a tubular member, having a tubular shape. The layered structure is arranged such that, at least when the lighting module is or has been mounted in the lighting device, there is at least one intervening space between at least two adjacent, opposing surfaces of the at least a portion of the sheet assembly, wherein the intervening space permits passage of fluid through the layered structure or tubular member by the fluid passing between the at least two adjacent, opposing surfaces. The at least one light-emitting element may be coupled to the sheet assembly. A lighting device comprising a lighting module and a method of manufacturing a lighting device are also disclosed.

While the present invention has been illustrated in the appended drawings and the foregoing description, such illustration is to be considered illustrative or exemplifying and not restrictive; the present invention is not limited to the disclosed embodiments. Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims. For example, instead of forming a tubular member exhibiting a layered structure by the arranging of the at least a portion of the sheet assembly 12 in a rolled-up arrangement by rolling the at least a portion of the sheet assembly 12 more than one turn, other shapes of the layered structure are possible. That is to say, the sheet assembly 12 may be arranged in a rolled-up arrangement that has been rolled more than one turn so as to form a layered structure that not necessarily has a tubular shape. Instead of a tubular shape other shapes are possible which may be formed from modules each of which may, in a compressed state such as described in the foregoing, have such a shape that it may pass the through-hole 21 of the light-transmissive envelope 2, and which modules in the released state (e.g., having been released from a releasably fixed arrangement such as described in the foregoing) may be changed into larger modules that may not pass the through-hole 21 of the light-transmissive envelope 2. The modules may in the released state for example have a shape similar to that of polygonal bars (such as, for example, triangular bars, rectangular bars, squared bars, pentagonal bars, hexagonal bars, heptagonal bars, octagonal bars etc.). A dimension of the cross section of such bar-shaped modules might vary in their length direction (like, e.g., pyramid shaped modules). In the released state such bar-shapes modules may comprise a structure having at least partly overlapping parts or portions, such as, for example, a rolled-up tubular structure having been rolled more than one turn.

In the appended claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. Any reference signs in the claims should not be construed as limiting the scope.

Claims

CLAIMS:

1. A lighting module (10) mountable in a lighting device (20), the lighting module comprising:

at least one carrier substrate (14) configured to support at least one light- emitting element (11);

the carrier substrate including an at least in part flexible sheet assembly (12), wherein at least a portion of the sheet assembly is arranged in a rolled-up arrangement that has been rolled more than one turn so as to form a layered structure, and wherein the layered structure is arranged such that, there is at least one intervening space (17) between at least two adjacent, opposing surfaces of the at least a portion of the sheet assembly, wherein the intervening space permits passage of fluid through the layered structure by the fluid passing between the at least two adjacent, opposing surfaces, and wherein the carrier substrate is further configured to support driver circuitry (16), the driver circuitry being electrically coupled to the at least one light-emitting element, and/or wherein the carrier substrate is further configured to support control circuitry configured to control the driver circuitry.

2. A lighting module according to claim 1, wherein the at least a portion of the sheet assembly has been rolled more than one turn into a releasably fixed arrangement such that the at least a portion of the sheet assembly by the rolling experiences an elastic compressive force along at least one length dimension of the layered structure.

3. A lighting module according to claim 1 or 2, wherein at least a portion of the sheet assembly is arranged in a rolled-up arrangement that has been spirally rolled more than one turn.

4. A lighting module according to any one of claims 1-3, wherein the layered structure has a cylindrical, conical or bar shape.

5. A lighting module according to any one of claims 1-4, wherein the layered structure is arranged such that there is a plurality of intervening spaces between the at least two adjacent, opposing surfaces of the at least a portion of the sheet assembly.

6. A lighting module according to claim 1, wherein the layered structure is arranged such that, at least when the lighting module has been mounted in the lighting device, there is at least one layer of the at least a portion of the sheet assembly between the at least one light-emitting element and at least a portion of the driver circuitry and/or the control circuitry.

7. A lighting module according to any one of claims 1-6, wherein the carrier substrate includes at least one radio -frequency antenna (15) integrated or encapsulated in the carrier substrate.

8. A lighting device (20) comprising a lighting module (10) according to any one of claims 2-7.

9. A lighting device according to claim 8 comprising a lighting module according to claim 2, wherein the lighting device comprises an at least in part light-transmissive envelope (2) within which the lighting module is mountable, wherein the light-transmissive envelope comprises a through-hole (21) for insertion of the lighting module within the light- transmissive envelope, wherein the elastic compressive force causes the at least a portion of the sheet assembly to become compressed so as to permit insertion of at least the sheet assembly within the light-transmissive envelope through the through-hole.

10. A method (90) of manufacturing a lighting device (20) comprising a lighting module (10) mounted within a light-transmissive envelope (2), the lighting module comprising at least one carrier substrate (14) configured to support at least one light-emitting element (11) and configured to support driver circuitry and/or control circuitry, wherein the carrier substrate comprises an at least in part flexible sheet assembly (12), the method comprising:

arranging (92) at least a portion of the sheet assembly in a rolled-up arrangement by rolling the at least a portion of the sheet assembly a more than one turn so as to form a layered structure; and mounting (93) the sheet assembly within the light-transmissive envelope; wherein the layered structure is arranged such that, at least when the lighting module is mounted within the at least in part light-transmissive envelope, there is at least one intervening space (17) between at least two adjacent, opposing surfaces of the at least a portion of the sheet assembly, wherein the intervening space permits passage of fluid through the layered structure by the fluid passing between the at least two adjacent, opposing surfaces.

11. A method according to 10, wherein the light-transmissive envelope (2) comprises a through-hole (21), and wherein the arranging of the at least a portion of the sheet assembly in a rolled-up arrangement by rolling the at least a portion of the sheet assembly (14) more than one turn so as to form a layered structure comprises:

rolling the at least a portion of the sheet assembly more than one turn into a releasably fixed arrangement such that the at least a portion of the sheet assembly by the rolling experiences an elastic compressive force along at least one length dimension of the layered structure, wherein the elastic compressive force causes the at least a portion of the sheet assembly to become compressed so as to attain a size that permits insertion of at least the sheet assembly within the light-transmissive envelope through the through-hole;

the method further comprising:

holding the at least a portion of the sheet assembly in the releasably fixed arrangement; and

inserting at least the sheet assembly within the light-transmissive envelope through the through-hole.

12. A method according to claim 11, further comprising, after having inserted at least the sheet assembly within the light-transmissive envelope, releasing the at least a portion of the sheet assembly from the releasably fixed arrangement, whereby the layered structure expands along the at least one length dimension of the layered structure based on at least a part of the elastic compressive force.

13. A method according to claim 12, wherein the elastic compressive force is such so as to, when the at least a portion of the sheet assembly is released from the releasably fixed arrangement, cause the layered structure to expand along the at least one length dimension of the layered structure such that the at least a portion of the sheet assembly attains a size that does not permit withdrawing at least the sheet assembly from the light- transmissive envelope through the through-hole.

14. A method according to any one of claims 10-13, wherein the arranging of the at least a portion of the sheet assembly in a rolled-up arrangement by rolling the at least a portion of the sheet assembly more than one turn so as to form a layered structure comprises spirally rolling the at least a portion of the sheet assembly more than one turn.