Night vision system utilizing a diode laser illumination module and a method related thereto

• US 6,429,429 B1
• Filed: 06/22/2000
• Issued: 08/06/2002
• Est. Priority Date: 06/22/2000
• Status: Expired due to Term

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Weber, Willes H., Fohl, Timothy, Remillard, Jeffrey Thomas
• Primary Examiner(s): Epps, Georgia
• Assistant Examiner(s): HASAN, MOHAMMED A
• Application Number:
  US09/598,284
• Time in Patent Office: 775 Days
• Field of Search: 250/353, 250/338.1, 250/339.06, 250/340
• US Class Current: 250/353
• CPC Class Codes: G02B 23/12 with means for image conversion or intensification
• CPC Class Codes: G02B 5/136 plural reflecting elements forming part of a unitary body G02B5/124 takes precedence
• CPC Class Codes: H04N 23/56 provided with illuminating means
• CPC Class Codes: H04N 5/33 Transforming infrared radiation cameras or camera modules for generating image signals from infrared radiation H04N23/20; circuitry of SSIS for transforming infrared radiation into image signals H04N25/20

Abstract

A night vision system 10 is provided for detecting objects at relatively low visible light levels. The system 10 includes an infrared light source 14. The system 10 further includes a thin sheet optical element 16 extending along a first axis 27 receiving light from the infrared light source 14 and reflecting the light generally in a first direction. Finally, the system 10 includes an infrared camera for receiving the light reflected off objects in the environment and generating a video signal responsive to the received light.

Claims

1. A night vision system, comprising:

an infrared light source;

a thin sheet optical element extending along a first axis receiving light from said infrared light source and reflecting said light generally in a first direction; and

,

an infrared camera for receiving said light reflected off of an object and generating a video signal responsive to said received light.

2. The night vision system of claim 1 wherein said infrared light source is an infrared diode laser.

3. The night vision system of claim 1 wherein said thin sheet optical element includes a first and second plurality of reflective facets, said first plurality of reflective facets receiving said light from said infrared light source and reflecting said light to a second plurality of reflective facets that further reflect said light from said thin sheet optical element generally in said first direction.

4. The night vision system of claim 3 wherein said thin sheet optical element includes a front surface, a back surface, a bottom surface, and a side surface connected between said front, back, and bottom surfaces, said bottom surface defining a first plurality of reflective steps extending along an axial length of said thin sheet optical element, said first plurality of reflective steps including said first plurality of reflective facets, said back surface defining a second plurality of reflective steps extending generally perpendicular to said first axis, said second plurality of reflective steps including said second plurality of reflective facets aligned to receive said light reflected from said first plurality of reflective facets and to further reflect said light through said front surface.

5. The night vision system of claim 1 wherein said thin sheet optical element is comprised of a polymeric material.

6. The night vision system of claim 1 wherein said thin sheet optical element further includes an aspheric lens disposed integral with or on said thin sheet optical element, said lens receiving said light from said infrared light source and collimating said light, said light being transmitted from said lens through said thin sheet optical element to said first plurality of reflective facets.

7. The night vision system of claim 1 further comprising a fiber optic cable transmitting said light from said infrared light source to said thin sheet optical element.

8. The night vision system of claim 1 further comprising an optical bandpass filter for filtering said light entering said infrared camera.

9. The night vision system of claim 1 further comprising a holographic diffuser or lens array disposed proximate said thin sheet optical element to diffuse said light being emitted from said thin sheet optical element.

15. The night vision system of claim 9 further comprising an optical bandpass filter for filtering said light entering said infrared camera.

10. A night vision system, comprising:

an infrared light source;

a thin sheet optical element having an aspheric lens and a first and second plurality of reflective facets, said aspheric lens being integral with or proximate to said thin sheet optical element and receiving light from said infrared light source and collimating said light;

said first plurality of reflective facets receiving said light from said aspheric lens and reflecting said light to said second plurality of reflective facets that further reflect said light generally in a first direction; and

,

an infrared camera for receiving said light reflected off of an object and generating a video signal responsive to said received light.

11. The night vision system of claim 10 wherein said infrared light source is an infrared diode laser.

12. The night vision system of claim 10 wherein said thin sheet optical element includes a front surface, a back surface, a bottom surface, and a side surface connected between said front, back, and bottom surfaces, said bottom 5 surface defining a first plurality of reflective steps extending along an axial length of said thin sheet optical element, said first plurality of reflective steps including said first plurality of reflective facets, said back surface defining a second plurality of reflective steps extending generally perpendicular to said first axis, said second plurality of reflective steps including said second plurality of reflective facets aligned to receive said light reflected from said first plurality of reflective facets and to further reflect said light through said front surface.

13. The night vision system of claim 10 wherein said thin sheet optical element is comprised of a polymeric material.

14. The night vision system of claim 10 further comprising a fiber optic cable transmitting said light from said infrared light source to said thin sheet optical element.

16. The night vision system of claim 10 further comprising a holographic diffuser or lens array disposed proximate said thin sheet optical element to diffuse said light being emitted from said thin sheet optical element.

17. A method of detecting objects utilizing a night vision system, comprising the steps of:

transmitting infrared light to a thin sheet optical element;

reflecting said light from said thin sheet optical element generally in a first direction from said thin sheet optical element;

receiving said light reflected off of an object; and

, generating a video signal responsive to said received light.

18. The method of claim 17, wherein said step of reflecting said light, includes the substeps of:

collimating said light entering said thin sheet optical element;

reflecting said light from a first plurality of reflective facets to a second plurality of reflective facets; and

,

reflecting said light from said second plurality of reflective facets generally in said first direction.

19. The method of claim 17 wherein said step of receiving said light reflected off of said object includes the substep of:

filtering said light through an optical bandpass filter.

20. The method of claim 17 further comprising the step of diffusing said light reflected from said thin sheet optical element.

21. A night vision system, comprising:

an infrared light source;

a light reflector receiving infrared light from said infrared light source and reflecting said light from a first reflective surface in said reflector to a second reflective surface in said reflector, said light being further reflected from said second reflective surface toward an object; and

,

an infrared detector configured to receive said light reflected off said object.

22. A night vision system, comprising:

an infrared light source;

a polymeric light reflector receiving infrared light from said infrared light source and reflecting said light toward an object; and

,

an infrared detector configured to receive said light reflected off said object.

23. A night vision system, comprising:

a light source generating light at a non-visible frequency;

a polymeric light reflector receiving said light from said light source and reflecting said light toward an object; and

,

a light detector configured to receive said light reflected off said object.

24. A night vision system comprising:

an infrared light source generating infrared light;

a light reflector having a transparent portion and a reflective surface, said infrared light moving through said transparent portion to said reflective surface, said surface reflecting said light toward an object; and

,

an infrared detector configured to receive said light reflected off said object.

25. A method for an detecting an object using a night vision system, comprising:

transmitting infrared light to a light reflector;

reflecting said light from a first reflective surface in said reflector to a second reflective surface in said reflector;

reflecting said light from said second reflective surface toward an object; and

,

receiving said light reflected off of said object utilizing an infrared detector.