Searchlights with diffusers for uniformly projecting light

• US 10,253,945 B2
• Filed: 12/12/2014
• Issued: 04/09/2019
• Est. Priority Date: 12/12/2014
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Jungwirth, Douglas R.
• Primary Examiner(s): Negron, Ismael
• Application Number:
  US14/568,939
• Publication Number:
  US 20160169473A1
• Time in Patent Office: 1,579 Days
• CPC Class Codes: F21S 8/003 Searchlights, i.e. outdoor lighting device producing powerful beam of parallel rays, e.g. for military or attraction purposes searchlights mounted on a vehicle B60Q1/245
• CPC Class Codes: F21V 13/10 the elements being reflectors and screens
• CPC Class Codes: F21V 3/049 Patterns or structured surfaces for diffusing light, e.g. frosted surfaces
• CPC Class Codes: F21W 2131/10 Outdoor lighting

Abstract

A searchlight including at least one diffuser for eliminating spatial non-uniformities in the illuminated beam. The searchlight may further include a reflector, with the diffuser(s) positioned in front of the reflector.

Claims

1. A searchlight apparatus for improving illumination from the searchlight by filling-in spatial non-uniformities in an illuminated beam, the apparatus comprising:

a lamp of the searchlight to radiate white light, which is produced by an arc generated between electrodes through a Xenon gas inside of the lamp,

wherein the white light produces the illuminated beam comprising the spatial non-uniformities in the form of shadows; and

at least one diffuser, which comprises a white light holographic diffuser, located in front of the lamp and a reflector of the searchlight, to receive and to pass the white light through to diffuse the illuminated beam such that the white light diffuses into the shadows in the illuminated beam and the illuminated beam is larger in size than without using the at least one diffuser,

wherein the at least one diffuser is a symmetric diffuser with a diffusion angle of approximately zero (0) degrees to approximately six (6) degrees or an asymmetric diffuser with a diffusion angle from approximately zero (0) degrees to approximately ten (10) degrees.

2. The apparatus of claim 1, wherein the reflector is a parabolic reflector.

3. The apparatus of claim 1, wherein the reflector is one of a converging reflector or a diverging reflector.

4. The apparatus of the claim 1, wherein the searchlight is housed within a housing.

5. The apparatus of claim 4, wherein the at least one diffuser is located within the housing of the searchlight.

6. A system for improving illumination from a searchlight by filling-in spatial non-uniformities in an illuminated beam, the system comprising:

a lamp of the searchlight to radiate white light, which is produced by an arc generated between electrodes through a Xenon gas inside of the lamp,

wherein the white light produces the illuminated beam comprising the spatial non-uniformities in the form of shadows;

at least one diffuser, which comprises a white light holographic diffuser, located in front of the lamp and a reflector of the searchlight, to receive and to pass the white light through to diffuse the illuminated beam such that the white light diffuses into the shadows in the illuminated beam and the illuminated beam is larger in size than without using the at least one diffuser,

wherein the at least one diffuser is a symmetric diffuser with a diffusion angle of approximately zero (0) degrees to approximately six (6) degrees or an asymmetric diffuser with a diffusion angle from approximately zero (0) degrees to approximately ten (10) degrees; and

a housing comprising the searchlight.

7. The system of claim 6, wherein the reflector is a parabolic reflector.

8. The system of claim 6, wherein the reflector is one of a converging reflector or a diverging reflector.

9. A method for improving illumination from a searchlight by filling-in spatial non-uniformities in an illuminated beam, the method comprising:

radiating, from a lamp of the searchlight, white light, which is produced by an arc generated between electrodes through a Xenon gas inside of the lamp,

wherein the white light produces the illuminated beam comprising the spatial non-uniformities in the form of shadows; and

receiving by and passing through at least one diffuser, which comprises a white light holographic diffuser, located in front of the lamp and a reflector of the searchlight, the white light to diffuse the illuminated beam such that the white light diffuses into the shadows in the illuminated beam and the illuminated beam is larger in size than without using the at least one diffuser.

10. The method of claim 9, wherein the reflector is a parabolic reflector.

11. The method of claim 9, wherein the reflector is one of a converging reflector or a diverging reflector.

12. The method of claim 9, wherein the method further comprises receiving by and passing through at least one Fresnel lens, located in front of the lamp and the reflector of the searchlight, the white light.

13. The method of claim 9, wherein at least one of the at least one diffuser is a symmetric diffuser.

14. The method of claim 13, wherein the symmetric diffuser has a diffusion angle of approximately zero (0) degrees to approximately six (6) degrees.

15. The method of the claim 9, wherein the searchlight is housed within a housing.

16. The method of claim 15, wherein the at least one diffuser is located within the housing of the searchlight.

17. The method of claim 15, wherein the at least one diffuser is located external to the housing of the searchlight.

18. The method of claim 9, wherein at least one of the at least one diffuser is an asymmetric diffuser.

19. The method of claim 18, wherein the asymmetric diffuser has a diffusion angle from approximately zero (0) degrees to approximately ten (10) degrees.

20. The method of claim 18, wherein the asymmetric diffuser has a diffusion angle in one of a vertical direction and a horizontal direction.