US20080020355A1

US20080020355A1 - Variable beam boresight device

Info

Publication number: US20080020355A1
Application number: US11/488,245
Authority: US
Inventors: C. Gil Young
Original assignee: Lockheed Martin Corp
Current assignee: Lockheed Martin Corp
Priority date: 2006-07-18
Filing date: 2006-07-18
Publication date: 2008-01-24

Abstract

A structure for visibly boresighting an invisible MILES-type laser beam emitted by a small arms transmitter to sights of a weapon intermittently projects a visible light beam that is parallel to the beam emitted by the MILES-type laser. Adjusting the visible beam to impinge on that portion of a target in the sights of the weapon also boresights the MILES-type laser to the weapon's sights.

Description

FIELD

The invention pertains to combat simulation systems. More particularly, the invention pertains to structure and methods of boresighting an infrared laser to sights of a weapon.

BACKGROUND

In known MILES-type combat simulation systems involving individual combatants, MILES-type small arms transmitters (SAT) are affixed to combatants' rifles, for example, or other similar small arms for purposes of the simulation. The MILES-type lasers emit an infrared beam which is intentionally not visible to the human eye. While this configuration is desirable for simulation purposes, it does present problems for boresighting the beam to the sights of the weapon. Various solutions had been implemented to solve this problem.
In a known implementation, a fixture can be used for purposes of boresighting the MILES beam to the sights of the weapon. While effective, the use of fixtures is costly, at times inconvenient, especially during times when the combatants are in the field preparing to or conducting a simulation, require logistics support, and have limited accuracy.
There continues to be a need for small arms transmitters which conveniently incorporate an intermittently usable visible laser beam for boresighting purposes. Preferably the source of the visible laser beam could be incorporated into the SAT without a need for substantial or expensive changes thereto. It is also necessary and preferable that the resultant multimode transmitter be easily adjustable for boresighting purposes and robust so as to retain boresight adjustment during firing exercises as well as during rough handling of the weapon.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of a small arms transmitter in accordance with the invention mounted on the barrel of a weapon;

FIG. 2 is a schematic diagram illustrating optical characteristics of the small arms transmitter of FIG. 1;

FIG. 3 is a view, partially in section, illustrating additional aspects of the small arms transmitter of FIG. 1; and

FIG. 4 is a sectional view illustrating an alternate embodiment of the small arms transmitter of FIG. 1.

DETAILED DESCRIPTION

While embodiments of this invention can take many different forms, specific embodiments thereof are shown in the drawings and will be described herein in detail with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention, as well as the best mode of practicing same, and is not intended to limit the invention to the specific embodiment illustrated.
In a disclosed embodiment, a visible laser beam, co-aligned with a MILES-type laser beam, is built into a small arms transmitter (SAT) so that a user can effectively see where the MILES-type beam is incident. The visible laser can be a laser diode emitting in the red region of the visible spectrum. Other-color laser diodes may be used instead of red, but red laser diodes are adequately visible for this application.
The user aims his/her weapon, using his/her normal sights, at a point on an easily-visible stationary target sufficiently distant so that the parallax introduced by the fact that the laser beams are not laterally co-located with the gun sight axis, is not significant. At 100 meters the parallax error is a few tenths of an mrad, which is smaller than the error in most boresighting operations.
One of the common retro-reflective, self-adhesive tapes can be attached to the target to enhance the visible-laser visibility. The SAT is then adjusted until the visible laser beam strikes the same point. The MILES laser beam, emitted by the SAT, which was previously co-aligned with the visible laser beam, is therefore boresighted to the weapon's sights.
In another aspect of the invention, the two laser diodes, along with their collimating lenses, are mounted in a SAT optics sub-assembly. At the time of manufacture the sub assembly frame is mounted on a precision fixture that simulates the angular orientation of the sub assembly when mounted in the SAT, with respect to the weapon-barrel angular orientation. The MILES laser diode is positioned so that the beam characteristics and angular direction are correct, and then cemented in place. The visible-laser diode is similarly positioned and adjusted so that its beam is collinear with the MILES laser beam. It is then also cemented in place. At this point in the procedure the two laser beams are aligned permanently parallel to one another and therefore boresighted to each other.
In yet another aspect of the invention, the optics sub-assembly is next installed into the SAT. In a disclosed embodiment, the sub-assembly is attached to the frame of the SAT by a ball joint, which will allow rotation in the two orthogonal directions while not allowing translation.
The sub assembly can be rotated about two orthogonal axes perpendicular to the optical axis of the MILES laser beam by two adjustment screws. In this way the two co-aligned laser beams are angularly moved with respect to the barrel of the weapon for boresighting to the angular orientation of the barrel.
In known SATs the boresight angular adjustment range is about +/−8 mrad, which has proven adequate. Collimating lenses having a focal length on the order of 15 mm can be included. Hence, the overall length of the SAT optics sub-assembly can be about 20 mm. A +/−8 mrad adjustment range translates into about 6 mils of translation at the location of manually operable adjustment screws.
The adjustment screws can have TEFLON plastic or other low-friction elements either on the end of the screw or on a pad that the screw contacts. Another approach is to include a flexible joint in each linkage between the adjustment screws and the laser assembly. Something of this nature is preferred because of the slight motion of the SAT optics sub-assembly transverse to one screw symmetry axis when the orthogonal screw is adjusted. The fine-thread adjustment screws can be configured to work against stiff springs to eliminate backlash, and to retain the boresight adjustment during blank firing and rough handling of the gun. Linear adjustments could be used as an alternate.
A protective window can be incorporated in the SAT. It provides an environmental seal because the SAT optics sub-assembly will move during the boresight adjustment.
In yet another aspect of the invention, it would be desirable if the beams for the MILES laser and the visible, boresighting laser passed through common SAT optics. For example and without limitation, a beam splitter could be used to fold the visible beam into coincidence with the MILES beam. Both beams could then be directed through a common collimating lens prior to exiting the SAT transmitter. The beams can be adjusted by laterally displacing the collimating lens using a simple two dimensional positioning device.
FIG. 1 illustrates a block diagram view of a small arms transmitter 12 in accordance with the invention. As illustrated in FIG. 1, the SAT 12 can be coupled to the barrel of a weapon B, for example the barrel of a rifle, by a removable mounting bracket 16. Those of skill in the art will understand that a variety of mounting brackets could be used without departing from the spirit and scope of the present invention.
SAT 12 emits an infrared MILES beam, invisible to the human eye, 20 and a visible boresighting beam 24. Both beams 20, 24 exit the SAT 12 displaced and parallel to one another.
It will be understood that the SAT 12 includes a housing or a frame 26 which incorporates the sources of the beams 20, 24 as well as any other appropriate optics. As described subsequently, the beams 20, 24 can be adjusted in unison for boresighting purposes.
FIG. 2 illustrates a schematic view of an optics sub-assembly 30 which can be carried within a frame or housing 26 which defines an interior region. The assembly 26 incorporates a source 20-1, for example a laser diode, of the invisible MILES laser beam 20. The assembly 30 also incorporates a second source 24-1 of the visible laser beam 24 which could emit monochromatic light of a wavelength visible to the human eye of any desirable color.
Each of the sources 20-1, 24-1 is located at a focal point of a respective collimating lens 20-2 and 24-2. Radiant energy which passes through the respective collimating lens 20-2, 24-2 is emitted from the frame or housing 26 as a respective beam 20, 24.
FIG. 3 illustrates additional details of the SAT 12. The sub-assembly 30 is carried within an interior region 26-1 of the housing or frame 26. It is preferably supported therein by a ball joint 34. It will be understood that other means of support could be used without departing from the spirit and scope of the present invention.
The housing 26 also carries a protective optically transparent window 36 to protect the sub-assembly 30 from external environmental conditions. Those of skill will understand that the window 36 could be formed of selected glass or plastic.
As illustrated in FIG. 3, the transmitter 12 incorporates an elevation adjustment screw 38-1 and an azimuth adjustment screw 38-2. In use, the simulation participant, under appropriate conditions, can energize the source 24-1 of the visible boresighting beam 24.
Using the adjustment elements 38-1, 38-2 the user can then aim the weapon using its normal sights at a point on an easily-visible stationary target. The target is selected such that it is sufficiently distant that any parallax introduced by the fact that the two beams 20, 24 are not laterally co-located with the sights of the weapon is insignificant.
The sub-assembly 30 can then be adjusted using adjusting elements 38-1, 38-2 so that the visible beam 24 is incident on the same point at which the weapon is being aimed using its normal sights. The MILES beam 20 emitted by source 20-1 was previously co-aligned with the visible beam 24. It is as a result boresighted to the weapon's sights.
For purposes of providing a stable orientation and adjustment of the sub-assembly 30, a spring 40, or other friction inducing element, can be associated with each of the adjustment elements 38-1, 38-2. Those of skill will understand that the housing or frame 26 of the SAT can be formed of metal, plastic or the like all without limitation.
FIG. 4 illustrates an alternate embodiment of a SAT 50. The SAT 50 incorporates a source, such as the source 20-1 of an infrared MILES laser beam and a source 24-1 of a beam of visible laser light. The beam emitted by the visible laser light, such as beam 24-2 is folded by a prism 52 and deflected by a beam splitter 54 so as to be coextensive with the beam 20-2 emitted by the MILES source 20-1. The composite beam passes through a collimating lens 56 and exits the SAT 50 via an environmental seal window 60. The collinear beams from the respective sources 20-1, 24-1 extend parallel to a common axis A and coextensive with one another.
An adjusting element such as element 62 can be used to laterally deflect the lens 56. An orthogonal adjustment screw, not shown, can be used to laterally deflect the lens in the orthogonal direction so that these two lens deflection directions will steer the two coincident beams to align them to the weapon sight axis. It will be understood that other adjusting elements and configurations to achieve the desired coextensive emission of the beams could be used without departing from the spirit and scope of the present invention.
From the foregoing, it will be observed that numerous variations and modifications may be effected without departing from the spirit and scope of the invention. It is to be understood that no limitation with respect to the specific apparatus illustrated herein is intended or should be inferred. It is, of course, intended to cover by the appended claims all such modifications as fall within the scope of the claims.

Claims

1. A small arms transmitter for a combat simulation system comprising:

a housing;

a multi-laser assembly carried by the housing, the assembly carries a first laser which emits a beam of light visible to a simulation participant, and a second laser which emits a beam of light not visible to the simulation participant, the two beams are emitted parallel to one another; and

at least one movable element, carried by the housing, the element alters emission orientation of the beams relative to the housing.

2. A transmitter as in claim 1 which includes a manually operable element to selectively activate the first laser.

3. A transmitter as in claim 1 which includes a second movable element, orthogonal to the one movable element.

4. A transmitter as in claim 1 which includes a mounting device for coupling the housing to a weapon.

5. A transmitter as in claim 1 which includes at least one optical lens carried by the housing.

6. A transmitter as in claim 1 where the movable element alters one of an elevation or an azimuth of the beams.

7. A transmitter as in claim 6 which includes a second movable element, orthogonal to the one movable element,

the second movable element alters the other of the elevation or the azimuth.

8. A transmitter as in claim 7 where the assembly is coupled to the housing by a deflectable mounting element.

9. A transmitter as in claim 8 where the mounting element deflects in response to at least one of elevation, or, azimuth adjustments.

10. A transmitter as in claim 3 where a ball joint adjustably attaches the assembly to the housing.

11. A transmitter as in claim 10 where the housing includes an optical window through which the beams pass.

12. An adjustable small arms transmitter comprising:

a housing having an optical window and defining an internal region;

first and second adjustment elements carried by the housing, spaced apart from one another; and

a structure that emits first and second beams of radiant energy, the structure is movably carried by the housing in the region, the beams pass through the window, the structure moves in response to the adjustment elements.

13. A transmitter as in claim 12 where the structure is coupled to the housing by a deflectable ball joint therebetween.

14. A transmitter as in claim 12 where the structure moves one of linearly or arcuately in response to the adjustment elements.

15. A transmitter as in claim 12 where the adjustment elements are independently movable linearly or arcuately.

16. A device comprising:

means for generating a first, visible, beam of radiant energy;

means for generating a second beam of radiant energy;

means for aligning both beams such that they are parallel to one another;

means for adjusting the beams arcuately and in unison;

a frame which carries the means for generating; and

means for attaching the frame to a weapon.

17. A device as in claim 16 which includes means for collimating the beams.

18. A device as in claim 16 where the means for adjusting comprises a deflectable ball joint having first and second ends with one end attached to the frame.

19. A device as in claim 18 where the means for generating the beams are carried by an optical sub-assembly, the sub-assembly is attached to the other end of the ball joint.

20. A device as in claim 19 where the sub-assembly includes at least one collimating lens.

21. A small arms transmitter comprising:

a housing;

a first source of a monochromatic beam of radiant energy;

a second source of human visible monochromatic beam of radiant energy, the first and second sources are displaced from one another and carried in the housing;

at least one optical element to deflect at least one of the beams with the beams emitted from the housing along a common center line.

22. A transmitter as in claim 21 where the optical element is selected from a class which includes at least a prism, a beam splitter and an optical lens.

23. A transmitter as in claim 22 which includes a manually movable beam adjusting element.

24. A transmitter as in claim 23 where movement of the beam adjusting element moves a collimating lens.

25. A transmitter as in claim 23 where the element is one of rotated or moved linearly to adjust at least one of the beams.