DE112007000458T5 - Optical display with recessed optical plate - Google Patents

Abstract

A light handling unit for use between a display panel and a backlight, the light handling unit having a display panel side facing the display panel and a backlight side facing the backlight, the unit comprising:
a grooved layer having a first light-handling layer, a cross member substantially parallel to and spaced from the first light-handling layer, and an array of first interconnecting members integral with the cross member, the first interconnecting members attached to the first light-handling layer ,

Description

Field of the invention

The This invention relates to optical displays, and more particularly to display systems, which are backlit, as in LCD monitors and LCD TVs can be used.

background

Liquid crystal displays (LCDs) are optical displays used in devices such as laptop computers, Calculators, digital clocks and televisions become. Some LCDs have a light source that faces the side of the display is arranged with a light guide on which arranged is to move the light from the light source to the back of the To conduct LCD panels. Other LCDs, for example some LCD monitors and LCD TVs (LCD TVs) are directly lit, using a number of light sources behind the LCD panel are arranged. This arrangement will be larger Increasingly popular because the light output requirements, to achieve a certain level of display brightness, with increase the square of the display size while the place for the arrangement of light sources along the Page of the display is available, only linear with the display size increases. In addition, some LCD applications require like LCD TVs, that the display is bright enough to get out of one greater distance than other applications to be considered, and the viewing angle requirements for LCD TVs are generally different from those for LCD monitors and hand-held devices.

Some LCD monitors and most LCD TVs are commonly used through a number of cold cathode fluorescent lamps (CCFLs) from behind illuminated. These light sources are linear and extend over the full width of the ad, with the result that the Back of the ad by a row of bright stripes illuminated, which are separated by darker areas. One such illumination profile is not desired, and therefore a diffuser plate is used to illuminate the lighting profile to smooth the back of the LCD device.

At present, LCD TV diffuser panels employ a polymer matrix of polymethyl methacrylate (PMMA), poly (carbonate), cycloolefins, random copolymers of polymethyl methacrylate or polystyrene combined with a variety of dispersed phases comprising glass, polystyrene beads and CaCO ₃ particles , These plates often deform or warp after exposure to the elevated temperatures of the lamps. In addition, in order to make the illumination profile on the backside of the LCD panel more uniform, some stray plates are provided with a scattering characteristic that varies spatially across its width. Such nonuniform diffusers are sometimes referred to as print pattern diffusers. They are expensive to manufacture and increase manufacturing costs because the scattering pattern must be matched at the time of assembly with the illumination source. In addition, the scattering plates require tailor-made extrusion mixing to evenly distribute the scattering particles throughout the polymer matrix, further increasing cost.

Around furthermore, a distortion or other types of physical To prevent twisting, the diffuser plate must be relatively have a minimum thickness to the height and width. If the Size of the display increases, it means that the Diffuser plate is also increasingly thick, and consequently the weight of the display increases.

Summary of the invention

A Embodiment of the invention is directed to a display system directed, which is a light source, a display panel and an arrangement of light-handling layers that exist between the light source and the display panel. The light source is illuminated the display panel through the arrangement of light-handling layers. The array of light-handling layers has a fluted Plate on which has a front layer facing the display panel, a rear layer facing the light source and a plurality of connecting elements which connect the front and back layers.

A Another embodiment of the invention is directed to a light handling unit directed, which has a grooved layer. The grooved layer has a first light-handling layer, a cross-member that is in the essentially parallel to the first light-handling layer and of her spaced, and an array of first connecting elements on which the cross member with the first light-handling layer connect.

These and other aspects of the present application will become apparent from the following detailed description clearly. In no case should the above summaries as limitations of the claimed Object, this object being only is defined by the appended claims, which will be changed during the prosecution can.

Brief description of the drawings

The Invention may be in consideration of the following detailed Description of various embodiments of the invention in conjunction with the attached drawings more complete be understood, in which like reference numerals the same elements describe. Show it:

1 schematically a display device that uses a fluted plate;

2A schematically a fluted plate;

2 B and 2C schematically fluted plates with attached optical films;

3 schematically a fluted plate having a spatially variable single-pass transmittance;

4 schematically a fluted plate having a spatially variable refractive index;

5A and 5B schematically fluted plates whose upper and lower layers each have spatially varying thicknesses;

6A and 6B schematically fluted plates whose upper and lower layers each have spatially varying thicknesses;

7A . 7B , and 7C schematically fluted plates having flutes of different cross-sectional shape;

8A schematically a plan view of a fluted plate showing parallel grooves arranged;

8B schematically a plan view of a fluted plate showing groups of parallel flutes which are arranged vertically;

9 and 10 schematically fluted plates with an optically useful surface structure;

11A . 11B . 12A and 12B schematically, various optical film assemblies having a fluted plate;

13A and 13B schematically the construction of a fluted plate using a spine, which is attached to an optical film;

14A and 14B schematically the construction of a fluted plate using a double-sided spine, which is attached to optical films;

15 and 16 schematically other film assemblies that are built around a double-sided back;

17 schematically the construction of a fluted plate, the first and second layers used having mutual connecting elements; and

18 schematically a display system having a heat transfer medium flow through grooves of the fluted plate.

While the invention for various modifications and alternative Forms are susceptible, their peculiarities become exemplary shown in the drawings and will be described in detail. It should, however, understand that it is the intention that Invention not to the particular embodiments described to restrict. On the contrary, it is the intention, all modifications, equivalents and to cover alternatives that are within the spirit and scope of the invention fall, which is defined by the appended claims is.

Detailed description

The The present invention is directed to liquid crystal displays (LCDs or LC displays) applicable, and is applicable to LCDs that directly from behind, and applicable to LCDs that illuminated by the edge, for example, LCDs used in LCD monitors and LCD TVs (LCD TVs).

The currently used in LCD TVs used diffuser plates on a polymer matrix, for example polymethyl methacrylate (PMMA), Polycarbonate (PC) or cycloolefins acting as a rigid plate is trained. The plate contains scattering particles, for example, organic particles, inorganic particles or voids (Blow). These plates often deform or warp after being exposed to the elevated temperatures of the light sources which are used to illuminate the display. These Plates are also more expensive to manufacture and in to assemble the final display device.

The present application discloses directly illuminated LCD devices having an array of light handling layers disposed between the LCD panel itself and the light source. The array of light-handling layers may comprise a diffuser layer whose transmissivity and haze levels are designed to be a directly illuminated LC display ge provide their brightness over the display is relatively uniform.

A schematic exploded view of an exemplary direct illuminated LC display device 100 is in 1 presents. Such a display device 100 can be used for example in an LCD monitor or LCD TV. The display device 100 is based on the use of an LC panel 102 which is typically an LC layer 104 which is between panel plates 106 are arranged. The plates 106 are often formed of glass, and may have electrode structures and alignment layers on their insides to control the orientation of the liquid crystals in the LC layer 104 exhibit. The electrode structures are usually arranged to define LC panel pixels, areas of the LC layer where the orientation of the liquid crystals can be controlled independently of adjacent areas. There may also be a color filter on one or more of the plates 106 to impose a color on the displayed image.

An upper absorption polarizer 108 is above the LC layer 104 and a lower absorption polarizer 110 is under the LC layer 104 arranged. In the illustrated embodiment, the upper and lower absorption polarizers are outside the LC panel 102 arranged. The absorption polarizers 108 . 110 and the LC panel 102 In combination, control the light transmission of the backlight 112 through the ad 100 to the viewer. In some LC displays, the absorption polarizers can 108 . 110 be arranged vertically with their transmission axes. If a pixel of the LC layer 104 is not activated, it can not change the polarization of light going through there. Consequently, light passing through the lower absorption polarizer 110 goes through the upper absorption polarizer 108 absorbed when the absorption polarizers 108 . 110 are aligned vertically. On the other hand, when the pixel is activated, the polarization of the light passing therethrough is rotated so that at least a portion of the light passing through the lower absorption polarizer 110 is passed through, even through the upper absorption polarizer 108 is allowed through. A selective activation of the different pixels of the LC layer 104 for example by a control device 114 causes the light to exit the display at certain desired locations, thus forming an image seen by the viewer. The controller may, for example, comprise a computer or television controller that receives and displays television images. There may be one or more optional layers 109 over the upper absorption polarizer 108 be provided to provide, for example, the display surface with a mechanical and / or environmental protection. In an exemplary embodiment, the layer 109 a hard coat over the absorption polarizer 108 exhibit.

It will be recognized that some sort of LC displays in one Way different from the one described above. For example, the absorption polarizers can be aligned in parallel be, and the LC panel can turn the polarization of the light, when it is in an inactive state. Nevertheless the basic structure of such ads remains similar to the above described.

The backlight 112 has a number of light sources 116 on, which generate the light, the LC panel 102 illuminated. There will usually be cold cathode linear fluorescent tubes extending across the display 100 extend than the light sources 116 in the display device 100 used. However, other types of light sources may be used, such as incandescent or arc lamps, light emitting diodes (LEDs), lasers, flat fluorescent panels, or external fluorescent lamps. It is not intended that this list of light sources be limiting or exhaustive, but only exemplary.

The backlight 112 can also have a reflector 118 to reflect the light coming from the light sources 116 down, in one direction from the LC panel 102 spreads away. The reflector 118 can also be useful to the light in the display device 100 reuse as will be explained below. The reflector 118 may be a specular reflector or may be a diffuse reflector. An example of a specular reflector acting as the reflector 118 can be used is the Vikuiti ^™ Enhanced Specular Reflection (ESR) film available from 3M Company, St. Paul, Minnesota. Examples of suitable diffuse reflectors include polymers such as polyethylene terephthalate (PET), polycarbonate (PC), polypropylene, polystyrene, and the like, which are loaded with diffusely reflecting particles such as titanium dioxide, barium sulfate, calcium carbonate, and the like. Other examples of diffuse reflectors containing microporous materials and fibril-containing materials are disclosed in US Pat U.S. Patent 6,780,355 (Kretman et al.).

It is an arrangement 120 of light handling layers between the backlight 112 and the LC board 102 arranged. The light-handling layers affect the light coming from the backlight 112 spreads to the operation of the display device 100 to improve. For example, an arrangement 120 of light-handling layers, a diffuser layer 122 exhibit. The diffuser layer 122 is used to scatter the light received from the light sources, resulting in an increase in the uniformity of the illumination light that is on the LC panel 102 meets. Consequently, this results in an image perceived by the viewer, which is more uniformly bright. The diffuser layer 122 may contain loose scattering particles distributed throughout the layer, or may have one or more surface scattering structures or a combination thereof.

The arrangement of light-handling layers 120 may also include a gain diffuser, a layer which diffuses light generally in the viewing direction. In some embodiments, a gain diffuser contains transparent particles that protrude from the surface of the film, thus providing refractive power to the light passing through the particles. This reduces the divergence of the light, resulting in an increase in on-axis brightness, sometimes called gain. Some types of gain diffusers are described in more detail in US Pat U.S. Patent No. 6,572,961 (Koyarna et al.).

The order 120 of light-handling layers can also be a reflection polarizer 124 exhibit. The light sources 116 typically produce unpolarized light, but the lower absorption polarizer leaves 110 only a single polarization state, and therefore about half of the light passing through the light sources 116 is generated, not to the LC layer 104 pass through. The reflection polarizer 124 however, it may be used to reflect the light that would otherwise be absorbed in the lower absorption polarizer, and therefore this light may be reflected by reflection between the reflective polarizer 124 and the reflector 118 be reused. At least part of it through the reflection polarizer 124 reflected light can be depolarized and then to the reflection polarizer 124 be reflected in a polarization state by the reflection polarizer 124 and the lower absorption polarizer 110 to the LC layer 104 is allowed through. In this way, the reflection polarizer 124 Be used to the fraction of light passing through the light sources 116 is emitted, increase the LC layer 104 reached, and therefore it is through the display device 100 generated image brighter.

It Any suitable type of reflection polarizer can be used for example, multilayer film optical (MOF) reflective polarizers; diffuse Reflective Polarisatinsfolie (DRPF), such as polarizers with a continuous / disperse phase, wireframe reflection polarizers or cholesteric reflective polarizers.

Both the MOF polarizers and the continuous / disperse phase polarizers rely on the refractive index difference between at least two materials, usually polymer materials, to selectively reflect light of a polarization state while transmitting light in an orthogonal polarization state. Some examples of MOF reflective polarizers are in co-owned U.S. Patent No. 5,882,774 (Jonza et al.). Commercially available examples of MOF reflective polarizers include the multi-layer reflective polarizers Vikuiti ^™ DBEF-D200 and DBEF-D440 which have diffusing surfaces available from 3M Company, St. Paul, Minnesota.

Examples of suitable DRPF include polarisers having a contiguous / disperse phase as in the co-owned U.S. Patent No. 5,825,543 (Ouderkirk et al.), And diffuse reflecting multilayer polarizers, as described, for. B. in the co-owned U.S. Patent No. 5,867,316 (Carlson et al.). Other suitable types of DRPF are in the U.S. Patent No. 5,751,388 (Larson).

Some examples of suitable wireframe polarizers include those described in U.S. Pat U.S. Patent No. 6,122,103 (Perkins et al.). Wire grid polarizers are commercially available from, among others, Moxtek Inc., Orem, Utah.

Some examples of suitable cholesteric polarizers include those described, for example, in U.S. Pat U.S. Patent No. 5,793,456 (Broer et al.) And im U.S. Patent 6,917,399 (Pekorny et al.). Cholesteric polarizers are often provided along with a quarter wave retardation layer on the output side, so that the light transmitted through the cholesteric polarizer is converted to linear polarization.

The order 120 of light-handling layers can also be a brightness-enhancing layer 128 exhibit. A brightness enhancing layer is one that has a surface structure that deflects off-axis light in a direction closer to the axis of the display. This increases the amount of light that moves on the axis through the LC layer 104 thus, the brightness of the image seen by the viewer is increased. An example is a prismatic brightness enhancement layer having a number of prismatic ridges that deflect the illumination light by refraction and reflection. Examples of prismatic brightness-increasing layers, which can be used in the display device include the Vikuiti ^™ BEFII and BEFIII family of prismatic films available from 3M Company, St. Paul, Minn., including BEFII 90/24, BEFII 90/50, BEFIIIM 90/50 and BEFIIIT.

The order 120 of light-handling layers may also be a carrier layer 130 which is used to provide a hold for the other light-handling layers. In some arrangements, one of the other light-handling layers in the carrier layer 130 be integrated. For example, some existing televisions have scattering particles in a relatively thick (2-3 mm), rigid polymer plate, thus combining the functions of providing retention and optical scattering in a single layer.

The carrier layer 130 Advantageously, it has a fluted plate which is a plate having flutes or recesses between the two surfaces of the plate. A cross-sectional view of an exemplary fluted plate 200 is shown schematically in 2A shown. The grooved plate 200 has a first layer 202 and a second layer 204 with fasteners 206 on that the first and second layers 202 . 204 connect. The recesses or open spaces 208 made by the fasteners 206 and the first and second layers 202 . 204 can be considered as fillets.

The grooved plate 200 is self-supporting and may be used in some exemplary embodiments to provide support to the other light-handling layers. The grooved plate 200 may be made of any suitable material, for example organic materials such as polymers. For example, the fluted plate 200 be formed using any suitable method, for example extrusion, molding and the like.

The thickness of the fluted plate 200 and the size of the fillets 208 can be selected depending on the particular application. For example, the fluted plate may be a few millimeters thick, for example, in the range of approximately 1 mm-4 mm, or may be thicker. The grooved plate 200 may also be thinner, for example having a thickness of approximately 50 μm or more. In addition, the center-to-center distance of the flutes 208 be selected to take any suitable value. For example, the distance may be in the range of about 1-4 mm or greater. In other embodiments, the fillet pitch may be smaller, for example down to about 50 μm or less.

The Using a fluted plate, the weight of a display system, like a TV. For example, weighs in a 40-inch LCD TV, a conventional massive diffuser plate typically about 2.3 lbs (1 kg), and accounts for about 5% of the total weight of the TV. A fluted plate only weighs a fraction of a comparable solid plate, in general about 25%, and therefore a fluted plate would only about Provide 1% of the total weight of the TV.

additionally the fluted plate has the mechanical advantages of a "double T-beam" with upper and lower plates up through an airspace and a connecting element are separated. Consequently, the fluted Plate a high resistance to warping and Rolling in under the severe lighting conditions ready typical in many display systems.

The Directions of the flutes can with respect to the Be oriented light sources in a desired direction. For example, if the light sources are elongated, as in Most fluorescent lamps, the flutes can do so be oriented that they are parallel to the light sources, or they can be so oriented that they do not are parallel. A specific orientation between the light sources and the fillets can for a given design of the Light source and the fluted plate improved illumination uniformity and also an improved thermal reaction, e.g. B. Provide warping, curling, etc.

Suitable polymeric materials for the fluted plate may be amorphous or semi-crystalline, and may comprise a homopolymer, copolymer or mixtures thereof. Polymeric foams can also be used. Exemplary polymeric materials include, but are not limited to: amorphous polymers such as poly (carbonate) (PC); Polystyrene) (PS); Acrylates, for example acrylic sheets as supplied under the trademark ACRYLITE ^® by Cyro Industries, Rockaway, New Jersey; Acrylic copolymers such as isooctyl acrylate / acrylic acid; Poly (methyl methacrylate) (PMMA); PMMA copolymers; cycloolefins; Cylcoolefincopolymere; Acrylonitrile-butadiene-styrene (ABS); Styrene-acrylonitrile copolymers (SAN); epoxides; Poly (vinylcyclohexane); PMMA / poly (vinylfluoride) blends; atactic poly (propylene); Poly (phenylene oxide) alloys; Styrene block copolymers; polyimide; polysulfone; Poly (vinyl chloride); poly (dimethylsiloxane) (PDMS); polyurethanes; Poly (carbonate) / aliphatic PET blends; and semi-crystalline polymers such as polyethylene) (PE); Poly (propylene) (PP); Olefin copolymers, such as PP / PE copolymers; Poly (ethylene terephthalate) (PET); Poly (ethylenenaphthalat) (PEN); Polyamide; ionomers; Vinyl acetate / polyethylene copolymers; cellulose acetate; Zellu loseacetatbutyrat; Fluoropolymers; Poly (styrene) -poly (ethylene) -Copoly mers; PET and PEN copolymers; and mixtures containing one or more of the listed polymers.

Some exemplary embodiments of the fluted plate 200 have polymeric materials that are substantially transparent to light. Some other exemplary embodiments may include a scattering material in the fluted plate 200 using, for example, a polymer matrix containing scattering particles. The polymer matrix may be any suitable type of polymer that is substantially transparent to visible light, for example, any of the above-listed polymeric materials.

The scattering particles can be any type of particle useful for scattering light, for example, transparent particles whose refractive index differs from the surrounding polymer matrix, diffusely reflecting particles, or voids or bubbles in the matrix. Examples of suitable transparent particles include solid or hollow inorganic particles, for example glass beads or glass dishes, solid or hollow polymer particles, for example solid polymer spheres or hollow polymer shells. Examples of suitable diffusely reflecting particles include particles or beads of PS, PMMA, polysiloxane, titanium dioxide (TiO ₂ ), calcium carbonate (CaCO ₃ ), barium sulfate (BaSO 4), magnesium sulfate (MgSO ₄ ), and the like. In addition, voids in the polymer matrix can be used to diffuse the light. Such cavities may be filled with a gas, for example air or carbon dioxide.

The fluted plate may be provided with other additives. For example, the fluted plate may contain antioxidants, such as Irganox 1010 available from Ciba Specialty Chemicals, Tarrytown, New York. Other examples of additives may include one or more of the following: a weathering agent, UV absorber, a hindered amine light stabilizer, a dispersing agent, a lubricant, an antistatic agent, a pigment or a dye, a nucleating agent, a flame retardant, a blowing agent or nanoparticles.

It can be the entire grooved plate 200 be formed of a scattering material, or selected portions of the fluted plate 200 can consist of a scattering material. For example, the first layer 202 , or the second layer 204 be formed of a scattering material, while the rest of the plate 200 is formed of a different material. In other embodiments, both the first and second layers may be 202 . 204 be formed of a scattering material. If a fluted plate 200 made of a diffusing material used in a display system as shown in FIG 1 is illustrated, the fluted plate provides a mechanical hold as well as providing a scattering function so that a separate diffuser layer can be eliminated.

In other exemplary embodiments, the fluted plate 200 with a diffuser layer 210 be provided, such as schematically in 2 B shown. The diffuser layer 210 can either be on the first layer 202 or the second layer 204 be attached. In addition, in some embodiments, there may be diffuser layers attached to each of the first and second layers 202 . 204 be attached. The diffuser layer 210 Can on the fluted plate 200 be attached using an adhesive layer (not shown), or in other embodiments, the diffuser layer 210 even be an adhesive layer on the fluted plate 200 is attached.

Commercially available materials suitable for use in a diffusing layer include 3M ^™ Scotchcal Diffuser Film, Type 3635-70 and 3635-30, and 3M ^™ Scotchcal ^™ ElectroCut ^™ Graphic Film, Type 7725-314 available from 3M Company, St. Paul, Minnesota are available. Other commercially available diffusers include acrylic foam tapes, such as 3M ^™ VHB ^™ Acrylic Foam Tape No. 4920.

In some exemplary embodiments, the diffuser layer 210 a scattering characteristic that is uniform across its width, in other words, the amount of scattering the light experiences is for dots across the width of the diffuser layer 210 the same.

The diffuser layer 210 can be optionally patterned, or by an optional patterned diffuser 210a be supplemented or replaced. The optional patterned diffuser 210a For example, it may have a patterned diffusing surface or a printed diffuser layer, such as titanium dioxide (TiO ₂ ) particles. The patterned diffuser 210a can on the diffuser layer 210 , between the diffuser layer 210 and the grooved plate 200 lie. In addition, a patterned diffuser on the fluted plate 200 be applied, which is at least partially formed of scattering material.

The grooved plate 200 may be provided with protection of ultraviolet (UV) light, for example by having a UV absorbing material or a material which is resistant to the effects of UV light. Suitable UV-absorbing compounds are commercially available, the z. Cyasorb ^™ UV-1164, available from Cytec Technology Corporation of Wilmington, Del. and Tinuvin ^™ 1577, available from Ciba Specialty Chemicals of Tarrytown, NY. The grooved plate 200 may also have brightness enhancing phosphors that convert UV light to visible light.

There may be other materials in the layers of the fluted plate 200 be included to reduce the adverse effects of UV light. An example of such a material is a hindered amine light stabilizing composition (HALS). In general, the most useful HALS are those derived from a tetramethylpiperidine and those which can be considered tertiary polymer amines. Suitable HALS compositions are commercially available, for example, under the trade name "Tinuvin" from Ciba Specialty Chemicals Corporation of Tarrytown, NY One such useful HALS composition is Tinuvin 622 , UV-absorbing materials and HALS are also used in the U.S. Patent No. 6,613,819 (Johnson et al.).

In other embodiments, the fluted plate 200 two diffuser layers 210 . 212 respectively at the first and second layers 202 . 204 the grooved plate 200 are attached. The diffuser layers 210 . 212 can each directly to the respective layer 202 . 204 the grooved plate 200 be applied as in 2C or may be attached using an adhesive layer (not shown).

The two diffuser layers 210 . 212 may have the same scattering properties, or may have different scattering properties. For example, the diffuser layer 210 one from the second diffuser layer 212 have different permeability or turbidity levels, or may be of a different thickness.

The optical properties of the fluted plate may be uniform across its width, but this is not necessary. In some exemplary embodiments, for example, those in U.S. Pat 3 shown fluted plate 300 can be the amount of spread caused by the fluted plate 300 itself is mediated, spatially across the width of the plate 300 vary. This can be achieved, for example, by introducing loose scattering particles unevenly over an extruded fluted plate. The graph above the fluted plate shows a spatial variation of the single-pass transmittance T. The single-pass transmittance is the fraction of the incident light passing through the fluted plate 300 higher permeability levels indicate less scattering and lower levels of permeability indicate higher scattering. In the example shown, the periodicity of the spatial variation of the transmission is equal to the distance between the connection elements 306 , Such spatial variation of the scattering may be useful to avoid unevenness in the brightness of the transmitted light due to the connecting elements 306 to reduce. However, there is no condition that the variation in T has this periodicity, and the variation in T may have a different periodicity or need not be periodic.

Another optical feature of the fluted plate, which over the fluted plate 400 may vary, the refractive index of one or both of the first and second layers 402 . 404 , as in 4 is shown schematically. Such a variation can be achieved, for example, by introducing a material with a different refractive index unevenly over an extruded fluted plate. The graph above the chamfered plate 400 shows a spatial variation of the refractive index. In the example shown, the periodicity of the spatial variation of the refractive index is equal to the distance between the connecting elements 406 , Such spatial variation of the scattering may be useful to avoid unevenness in the brightness of the transmitted light due to the connecting elements 406 to reduce. However, there is no condition that the variation of the refractive index has this periodicity, and the variation of the refractive index may have a different periodicity or need not be periodic.

In some exemplary embodiments, one or more of the layers of the fluted plate may have a thickness that varies across the plate. For example, in the fluted plate varies 500 that is schematically in 5A is shown, the thickness of the first layer 502 of it, at the edge of the plate 500 to be relatively thin, to, in the middle of the plate 500 to be relatively thick while the second layer 504 maintains a constant thickness over its width. A variation of the thickness of the first layer 502 may be used, inter alia, to provide additional strength to the plate or to provide a variation in the optical properties of the plate. In an illustrative example where the first layer 502 contains a uniform concentration of loose scattering particles, a variation of the thickness of the first layer 502 be used to provide a spatially varying Streucharakteristik. In the example shown, there is greater scattering of the light passing through the central portion of the plate 500 goes, as at the edge.

In other embodiments, the second layer 504 , or both the first and second layers 502 . 504 have a variable thickness. Like in 5B shown, has a fluted plate 520 a first layer 522 uniform thickness and a second layer 524 variable thickness. It will be appreciated that variations in the thickness of the first and / or second layers 502 . 504 . 522 . 524 may be periodic or non-periodic.

In some embodiments, the surfaces of the material surrounding the recesses or flutes may be parallel or perpendicular to the outer surfaces of the fluted plate, but this is not a necessary condition. In some exemplary embodiments, the surfaces of the first or second layer that define the flutes may be non-parallel to the top of the fluted plate. This is shown schematically in 6A for a special grooved plate 600 shown in the bottom 602a the first layer 602 to the top 604b the second layer 604 for at least some of the fillets 608 is not parallel. Consequently, the cross-sectional shapes of some of the flutes 608a not square or rectangular.

The underside of the groove may also be non-parallel to the underside of the second layer. For example, in the embodiment of FIG 6B the thicknesses of both the first and second layers 622 . 624 across the width of the plate 620 not even. In other exemplary embodiments, the first layer may be uniformly thick while only the second plate has an uneven thickness.

The flutes do not need to be quadrilateral in shape and may take other forms. For example, in one exemplary embodiment, incorporated in FIG 7A is shown schematically, the fluted plate 700 triangular shaped fasteners 706 on that between the first and second layers 702 . 704 connect. Consequently, the grooves can also 708 have a triangular cross-section. In another exemplary embodiment, incorporated in 7B is shown schematically, has the fluted plate 720 upper and lower layers 722 . 724 on, the sinusoidal insides 722a . 724a which have the fillets 728 define. The connecting elements 726 are formed where the sinusoidal surfaces meet.

In another exemplary embodiment, incorporated in 7C is shown schematically, has the fluted plate 730 upper and lower layers 732 . 734 on, over curved connectors 736 connected to each other. In the illustrated embodiment, the curved connecting elements alternate 736 between a curvature in one direction and the opposite direction to produce a wave effect.

It may be in addition to those shown herein many other cross sections for the fasteners and the fillets are used. Furthermore, the illustrated Embodiments presented for illustrative purposes only, and there is no intention to limit the scope of the invention to those only To restrict cross sections presented herein.

In some exemplary embodiments, for example, the fluted plate 800 , in the 8A is shown schematically, which is a plan view of the plate 800 shows are the fillets 808 arranged linearly and parallel to each other. In other exemplary embodiments, for example, the fluted plate 820 , in the 8B is shown schematically, the flutes 828 however, are linear with a first group of flutes parallel to each other and a second group of flutes 828 arranged, which are parallel to each other, but perpendicular to the first group. In other embodiments, different flutes may be at different angles to one another.

In some embodiments, the surface of the first or second layer may be planar and provided with an antireflection coating. In other embodiments, the first and / or the second layer may provide an optical function. For example, the outer or inner surfaces of the first and / or second layers may be provided with a matte finish. In another exemplary embodiment, the first and second layers may be provided with a surface structure. For example, the fluted plate 900 , in the 9 is shown schematically, first and second layers 902 . 904 on that over fasteners 906 attached to each other. In this particular embodiment, the top is 910 the first layer 902 with a series of prismatic ribs 912 Mistake. Ribs 912 may be parallel to each other, in which case the surface 910 like a prismatic brightness-enhancing layer works, the slightly off-axis light by a beam of light 914 is illustrated, so distracts that it is in one to the axis 916 more parallel direction propagates.

The fluted plate may have other types of surfaces. In another example, that in 10 is shown schematically, the first layer 1002 the grooved plate 1000 a top 1010 put on a set of lenses 1012 that has the light 1014 going through the plate to provide a refractive power. The lenses 1012 may have a width equal to the distance between the connectors 1006 is, but this is not required. The lenses 1012 can be lenticular lenses that span the width of the plate 1000 extend. This lens type is particularly well suited to a plate made using an extrusion process. Other methods can be used to make the lenses 1012 to form, such. B. forms.

The fluted plate can be used to hold other optical layers in a display. For example, one or more other layers may be attached to the fluted plate. The following examples are presented to show some possible combinations of other layers with a fluted plate. 11A shows an arrangement 1100 optical layers containing a chamfered plate 1101 with a reflective polarizer layer 1110 which is at the top of an upper layer 1102 the fluted plate is attached. The reflection polarizer layer 1110 may be attached using an adhesive, for example a clear adhesive or an optically scattering adhesive. It can be a prismatic brightness enhancing layer 1112 over the reflective polarizer layer 1110 be attached. In some exemplary embodiments, it may be desirable for at least a portion of the light to enter the brightness enhancing layer through an air interface or an interface that transitions from a low to a high refractive index 1112 entry. Therefore, a layer having a low-index material, for example, a fluorinated polymer, may be interposed between the brightness-enhancing layer 1112 and the next layer under the brightness enhancing layer 1112 to be ordered.

In other exemplary embodiments, an air gap may exist between the brightness enhancing layer 1112 and the layer under the brightness enhancing layer 1112 be provided. One approach to providing the air gap is on one or both opposing surfaces of the brightness enhancing layer 1112 and the layer under the brightness-enhancing layer 1112 to record a structure. In the illustrated embodiment, the bottom is 1114 the brightness-enhancing layer 1112 with projections 1116 structured, which touch the adjacent layer. There are thus cavities 1118 between the projections 1116 formed, with the result that light entering the brightness enhancing layer 1112 at a position between the projections 1116 enters, it enters through an air interface. In other embodiments, the reflective polarizer layer 1110 be omitted and the prismatic brightness enhancing layer 1112 directly on the grooved plate 1101 be attached. In some embodiments, the fluted layer 1101 provide an optical scattering, or a separate scattering layer may be provided, for example on a lower layer 1104 the grooved layer 1101 is attached or at the first layer 1102 the grooved layer 1101 between (i) the recessed layer and (ii) the reflective polarizer layer 1110 and / or the prismatic brightness enhancing layer 1112 is attached.

Other approaches to forming cavities and thus providing an air interface for light entering the brightness enhancement layer may be used. For example, the brightness enhancement layer may have a flat bottom, with the adjacent layer being structured with protrusions. These and additional approaches will be available in the U.S. Patent No. 7,010,212 (Emmons and others). Each of the embodiments of a fluted plate discussed herein may be adapted to provide an air interface for light entering the brightness enhancing layer.

The order of slides attached to the fluted plate 1101 attached, may be different. For example, a reflective polarizer layer 1110 on the prismatic surface of the brightness enhancing layer 1112 be attached, and the brightness-enhancing layer 1112 is at the fluted plate 1101 attached. This arrangement 1120 is in 11B shown schematically. The attachment of optical films to the prismatic surface of a brightness enhancement layer is further described in U.S. Pat U.S. Patent No. 6,846,089 (Stevenson et al.).

An exemplary embodiment comprising an assembly 1200 in which one or more films are attached to the bottom layer of the fluted plate is shown in FIG 12A shown schematically. In this embodiment, a reflection polarizer 1210 at the second layer 1204 the grooved plate 1201 attached, and a prismatic brightness enhancing layer 1212 is at the first layer of the fluted plate 1201 attached. It can be an optional diffuser layer 1214 at the bottom of the reflection polarizer 1210 be attached. In other embodiments, the fluted plate itself may provide scattering. In such a case, it may be desirable for the fluted plate 1201 the light passing through the reflection polarizer 1210 has not depolarized significantly.

Another exemplary embodiment shape 1220 a fluted plate 1201 , which is attached to an array of light-handling sheets, is incorporated in 12B shown schematically. In this embodiment 1220 is a diffuser layer 1222 on the grooved plate 1201 attached. It is an intermediate layer 1224 on the diffuser layer 1222 arranged, and a prismatic brightness-increasing layer 1226 is above the interlayer 1224 arranged. The diffuser layer 1222 may be, for example, an acrylic foam tape: the foam tape deforms when the intermediate layer 1224 is pressed into the foam tape, wherein a recessed area is created, in which the intermediate layer sits. The intermediate layer 1224 may have an optical function: for example, the intermediate layer 1224 a reflection polarizer film. Examples of other suitable arrangements of light-handling sheets that can be used with a fluted plate are described in more detail in U.S. Application Publication No. US Pat. 2006/0082699 (Gehlsen et al.).

In addition to forming, there are other methods of making a corrugated plate. One method is to attach a back to which already fasteners are attached to another optical film. This approach is used in the 13A and 13B shown schematically. The back 1302 has a cross element 1304 and an array of connectors 1306 on. The connecting elements 1306 can in the cross element 1304 be integrated. For example, the back 1302 be formed by molding or extrusion. The back 1302 can be formed from the same types of materials as previously explained for a fluted plate. Consequently, the back can 1302 be formed of an optically transparent or optically scattering material.

It will be an optical film 1310 at the connecting elements 1306 attached. The optical film can be any suitable type of film. For example, the foil 1310 a prismatic brightness enhancing film, a diffuser film, a reflection polarizer film, a reinforcing diffuser film, a lens sheet, an absorption polarizer, a matte film, or the like. In addition, the optical film 1310 just be a transparent foil. Furthermore, optical films can also on the back 1302 under the cross element 1304 be attached.

13B shows the optical film 1310 attached to the fasteners 1306 is attached. The foil 1310 can be attached to the fasteners using any suitable method. For example, the bottom can 1312 the foil 1310 and / or the tips 1314 the connecting elements 1306 with an adhesive that is cured after the bottom 1312 and the connector tips 1314 are arranged in contact. In a different approach, in which the slide 1310 and the connecting elements 1306 both are formed of polymeric materials, the film can 1310 and the connecting elements 1306 be placed in contact before the respective polymer materials are fully crosslinked, and the film 1310 and the connecting elements 1306 are then networked together. Several other approaches may be used, for example, to contact the optical film immediately following extrusion with the molten polymer to create a bond between the optical film and the fillets. In another approach, the fillets (after extrusion) may be heated and laminated at a later time. In addition, a coextruded fillet may also be employed whereby the fillet is formed from a material such as the matrix (non-adhesive blank) with a material which is coextruded at the tip (tacky material).

After the slide 1310 has been fastened, form the foil 1310 and the back 1302 together a plate, the fillets 1316 having.

In another embodiment, schematically in the 14A (separate elements) and 14B (Attached elements) is shown, has a back 1402 Sets of fasteners 1406a . 1406b on respective sides of a cross element 1404 on. There can be two optical films 1410a . 1410b at the respective sets of fasteners 1406a . 1406b be attached. The optical films 1406a . 1406b may be any desired type of optical film such as a transparent film, a diffuser film, a prismatic brightness-enhancing film, a reflective polarizing film or the like.

After at least one of the slides 1410a . 1410b on the back 1402 The foils form 1410a and 1410b and the back 1402 together a plate, the fillets 1416 having.

A particular embodiment of an arrangement 1500 optical films that have a back 1502 of in 14B illustrated type is in 15 shown schematically. In this embodiment, a diffuser layer 1510 at the lower connecting elements 1506b attached, and a prismatic brightness enhancing layer 1512 is attached to the upper connecting elements. It may optionally have a reflective polarizer layer 1514 on the structured side of the prismati brightness-enhancing layer 1512 be attached.

Another illustrative arrangement 1600 is in 16 shown schematically, in which the reflection polarizer 1514 between the diffuser layer 1510 and the back 1502 is arranged.

Another approach to attach two layers together is to use layers that are mutually connectable. For example, the two layers may be mechanically attachable to each other using a fastening mechanism such as that used to seal food storage bags. An exemplary embodiment of such a mechanism will be described in US Pat 17 represented, the parts of the upper and lower layers 1702 . 1704 shows. every layer 1702 . 1704 has respective mutual connection elements 1706 . 1708 which are directed to the other layer. If the two layers 1702 . 1704 be compressed, lock the mutual fasteners 1706 . 1708 with each other to form the fasteners. The layers 1702 . 1704 with the respective mutual connecting elements 1706 . 1708 For example, they can be formed using an extrusion process. The mutual fasteners 1706 can have the same shape as the mutual fasteners 1708 but this is not required.

If Backs are used to the upper and lower layers to join or not, the fluted plate can in part continuous processes are formed. The slides that the upper and lower layers, and the opti onal back can be subtracted from respective roles and to each other be attached. Once the layers are attached together, the resulting grooved product is relatively proportionate stiff. Individual plates can be chipped from the continuous one Product to be cut off.

A fluted plate can be used to enhance heat management in a display system such as a television display or monitor. An exemplary embodiment of a display system 1800 , this in 18 is shown schematically, has one or more light sources 1802 , a chipped plate 1804 an arrangement of light-handling layers 1806 and a display panel 1808 on. There may be a coolant through the fillets of the fluted plate 1804 flow, resulting in a lower operating temperature of the display system. The coolant may be air, and in some embodiments, the air may simply flow through vertically oriented flutes due to natural convection. In other embodiments, the coolant may be forced through the fillets by a coolant circulation device. For example, a fan 1810 Be used to air through the flutes of the fluted plate 1804 to press. In other embodiments, a transparent liquid, such as water, may be forced through the fillets by a pump.

It it will be realized that there are many other possible ones Arrangements are within the scope of the invention, in which others Layers in other orders from bottom to top in the arrangement, or in other positions relative to the back.

The The present invention should not be considered to be is limited to the specific examples described above rather, it should be understood that they are all Aspects of the invention, which is defined in the appended claims be clearly stated. It will easily be different modifications, equivalent Method, as well as numerous structures to which the present Invention may be applicable to those skilled in the art to which the the present invention, upon review of the present Description will be apparent. For example, too freestanding optical films in a display device next to a beveled plate used on other optical layers is attached. Also, an ad may have more than one gutted one Use plate. The flutes of the several fluted plates may be arranged parallel to each other, or the flutes a plate can not be parallel to the grooves of a be oriented to another fluted plate. The requirements are intended to cover such modifications and devices.

Summary

A display system includes a light source, a display panel, and an array of light handling layers disposed between the light source and the display panel. The light source illuminates the display panel through the array of light-handling layers. The array of light-handling layers has a fluted plate having a front layer facing the display panel, a back layer facing the light source, and a plurality of interconnecting elements interconnecting the front and back layers. In some embodiments, the fluted plate has a first light-handling layer, a cross member substantially parallel to and spaced from the first light-handling layer, and an array of first interconnecting elements that support the cross member and the cross-member connect first light-handling layer.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

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Claims (19)

Light handling unit for use between a display panel and a backlight, wherein the Light handling unit a display panel side for orientation to the display panel and a backlight page to Orientation towards the backlight out, the Unit comprising: a grooved layer that is a first Light-handling layer, a transverse element that is essentially parallel to the first light-handling layer and is spaced therefrom, and an arrangement of first connecting elements, the are integral with the transverse element, wherein the first connecting elements attached to the first light-handling layer. The unit of claim 1, wherein the first light-handling layer a diffuser layer, a brightness enhancing layer or a Reflective polarizer has. The unit of claim 1, further comprising a second light-handling layer which is attached to the grooved layer. A unit according to claim 3, wherein an arrangement second Connecting elements, the second light-handling layer and the cross member combines. The unit of claim 3, wherein the second light-handling layer is connected to the first light-handling layer so that the first light-handling layer between the cross member and the second Light handling layer is located. A unit according to claim 1, wherein the first connecting elements are arranged on a display panel side of the cross member and extend from the cross member, wherein the unit further comprises second connecting elements on a backlight side of the cross member are arranged, wherein the second connecting elements of Transverse element, and further comprising a second light-handling layer has, which is attached to the second connecting elements. A display system comprising: a light source; one Display panel; and an arrangement of light-handling layers, which is arranged between the light source and the display panel are that the light source the display panel through the arrangement illuminated by light-handling layers, the arrangement of Light handling layers has a fluted plate, wherein the fluted plate has a front layer leading to the display panel has a back layer facing the light source and a plurality Connecting elements comprising the front and rear layer connect. The system of claim 7, wherein the array of light-handling layers a reflective polarizer layer, a diffuser layer and / or a having prismatic brightness enhancement layer. The system of claim 7, wherein at least a portion the fluted plate formed of a scattering material is. The system of claim 7, wherein the array of Light-handling layers further comprise a diffuser layer, a reflective polarizer layer and / or having a prismatic brightness enhancing layer. System according to claim 7, wherein the front and / or rear layer has a first light-handling layer. The system of claim 11, wherein the first light-handling layer a prismatic brightness enhancing layer, a diffuser layer and / or a reflective polarizer layer. The system of claim 11, wherein the connecting elements have first and second connecting elements, wherein the first Fasteners attached to a cross member and with the front layer are connected, the second connecting elements attached to the cross member and connected to the rear layer are the first light-handling layer on the first connecting elements and / or the second connecting elements is attached, and the further comprises a second light-handling layer associated with the other of the first connection elements and the second connection elements connected is. The system of claim 7, further comprising a controller coupled to control an image formed by the Display panel is displayed. The system of claim 7, wherein the display panel a liquid crystal display (LCD). The system of claim 7, further comprising a coolant circulation device for pressing a cooling medium through fillets the fluted plate has. The system of claim 16, wherein the coolant circulation device is a fan and the coolant is air. A system according to claim 7, wherein flutes of the fluted Plate are arranged vertically to a natural convection passage to allow air through there. System according to claim 7, wherein the connecting elements first fasteners attached to the front layer are, and second connecting elements, which at the rear layer are attached, wherein the first connecting elements mutually are locked with the second connecting elements.