Method and apparatus for generating a visible image with an infrared transmissive window

• US 20020135571A1
• Filed: 12/21/2000
• Published: 09/26/2002
• Est. Priority Date: 12/21/2000
• Status: Active Grant

• Current Assignee: Raytheon Company (Rtx Corporation)
• Original Assignee: Raytheon Company (Rtx Corporation)
• Inventors: Weimer, Wayne A., Rester, David H., Klocek, Paul
• Granted Patent: US 6,833,822 B2
• Time in Patent Office: Days
• US Class Current: 345/204
• CPC Class Codes: G02B 23/12 with means for image conversion or intensification
• CPC Class Codes: G03H 1/2249 Holobject properties
• CPC Class Codes: G03H 2001/0055 in advertising or decorative art
• 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 vehicle (10) includes an infrared imaging system (11). The system includes an infrared camera (12) positioned in the center of the front grille of the vehicle. The infrared camera includes a window (13) that has a holographic fringe pattern (14) which cooperates with visible light rays (27, 47, 52, 57) to generate an image (29) that is visible at a location spaced from the vehicle. The visible image may, for example, be a trademark or other symbol identifying the manufacturer of the vehicle. Infrared radiation (31) passes through the element and the structure thereof without significant change, and is detected by an infrared detector (33). A visible image corresponding to the infrared radiation is ultimately displayed by a head up display (19) on a portion (16) of the vehicle windshield (17).

Claims

1. An apparatus comprising an element which includes structure that cooperates with visible light rays to generate an image which is visible at a location spaced from said element, wherein infrared radiation passes through said element and said structure thereof without significant change.

2. An apparatus according to claim 1, wherein said structure includes a fringe pattern for a hologram.

3. An apparatus according to claim 2, wherein said element has a surface and wherein said fringe pattern is embossed in said surface of said element.

4. An apparatus according to claim 1, further comprising a light source which emits visible light rays, wherein said structure cooperates with light rays emitted by said light source to generate said image.

5. An apparatus according to claim 4, wherein said element has a front surface and a rear surface, said location being on a side of said element corresponding to said front surface, and said light source projecting light rays onto one of said front and rear surfaces.

6. An apparatus according to claim 1, further comprising a frame, said frame supporting said element and including a light source, wherein said light source emits light rays that cooperate with said structure to generate said image.

7. An apparatus according to claim 1, wherein said element includes a material and a dye disposed in said material.

8. An apparatus according to claim 1, wherein said element is a polymeric transmissive material that passes infrared radiation having a wavelength in the range of approximately 8-12 micrometers.

9. An apparatus according to claim 1, wherein said element includes a sheet and a member made of different materials, said sheet being coupled to said member and said sheet including said structure.

10. An apparatus according to claim 1, further comprising an infrared detector, said infrared detector receiving infrared radiation which has passed through said element.

11. An apparatus according to claim 10, wherein said infrared detector is an uncooled detector, said uncooled detector having an array of detector elements for detecting infrared radiation impinging thereon.

12. An apparatus according to claim 11, further comprising a lens section positioned optically between said element and said infrared detector, said lens section focusing infrared radiation which has passed through said element onto said infrared detector.

13. An apparatus according to claim 12, further comprising a circuit and a display, said display including a surface, said circuit receiving from said infrared detector electrical information representative of infrared radiation detected by said infrared detector, and providing on said surface a visible image of a scene corresponding to the infrared radiation.

14. An apparatus according to claim 13, further comprising a vehicle with a windshield, said surface being an inner surface of said windshield, said vehicle including said display, said element, said lens section, and said infrared detector.

16. A method according to claim 15, further comprising the step of focusing infrared radiation which has passed through said element onto an infrared detector using a lens section, said lens section being positioned optically between said element and said infrared detector.

17. A method according to claim 15, further comprising the step of selecting as said structure a fringe pattern for a hologram.

18. A method according to claim 15, further comprising the step of generating visible light rays with a light source, said light rays being affected by said structure to generate said visible image.

15. A method comprising the steps of:

generating a visible image by causing visible radiation to cooperate with structure of an element in a manner so that the visible image is visible at a location spaced from said element; and

passing infrared radiation through said element and said structure thereof without significant change in the infrared radiation.