Imaging and tracking sensor designed with a sandwich structure

• US 4,939,369 A
• Filed: 10/04/1988
• Issued: 07/03/1990
• Est. Priority Date: 10/04/1988
• Status: Expired due to Fees

• Current Assignee: BAE Systems Information and Electronic Systems Integration Incorporated (BAE Systems Plc)
• Original Assignee: Loral Fairchild Corp. (Newell Brands Inc.)
• Inventors: Elabd, Hammam
• Primary Examiner(s): Howell, Janice A.
• Assistant Examiner(s): HANIG, RICHARD E
• Application Number:
  US07/253,271
• Time in Patent Office: 637 Days
• Field of Search: 250/332, 250/330, 250/338.1, 250/338.4, 250/339, 250/370.01, 250/370.08, 250/370.14, 357/30 C
• US Class Current: 250/332
• CPC Class Codes: G01S 7/486 Receivers
• CPC Class Codes: H01L 27/14643 Photodiode arrays; MOS imagers
• CPC Class Codes: H04N 25/00 Circuitry of solid-state image sensors [SSIS]; Control thereof

Abstract

A multi-function imaging and tracking device is disclosed. A first Schottky diode array lying in a first plane performs a tracking and acquisition function. A second Schottky diode array lying in a second plane performs an imaging function. The first array is a low resolution, high-speed array while the second array is a high resolution, low-speed array. The second array having an operational parameter to be adjusted by the first array.

Claims

1. Apparatus for detecting and imaging a target comprising:

(a) means for detecting light reflected from the target, said means for detecting comprising a low angular resolution array;

(b) means for imaging a target detected by the means for detecting, said means for imaging comprising a higher angular resolution array; and

(c) means for control of said means for imaging connected to said means for detecting, said means for detecting light controlling said means for imaging the target.

3. Apparatus as recited in claims 1 or 2 further comprising means for transmitting light to the target, said light detected by said means for detecting.

4. Apparatus as recited in claims 1 or 2 further comprising means for transmitting light to the target, said light detected by said means for detecting, wherein said means for transmitting light is selected from the group of lasers, LEDs, and phase arrays thereof.

5. Apparatus as recited in claim 4, wherein said means for transmitting light transmits a beam selected from the group of coded and modulated beams.

6. Apparatus as recited in claims 1 or 2, wherein said means for detecting and said means for imaging are mounted on a structure selected from the group of an aircraft, a satellite, a missile, and an industrial platform.

7. Apparatus as recited in claims 1 or 2, further comprising a lens, said lens focusing light of a first wavelength of interest from the target on said imaging array and projecting light of a second wavelength of interest on said means for detecting.

8. Apparatus as recited in claim 7, wherein said means for detecting is mounted between said lens and said means for imaging, said means for detecting sensing light of a different wavelength than said means for imaging.

9. Apparatus as recited in claim 7 further comprising a 3-5 μ

m and 1.06 μ

m filter between said lens and said means for detecting.

10. Apparatus as recited in claims 1 or 2, wherein said means for detecting and said means for imaging are both in a low-temperature bath.

11. Apparatus as recited in claim 10, wherein said low-temperature bath is selected from the group of liquid nitrogen dewars, Joule Thompson cryostats, sterling cycle refrigerators and passive coolers.

13. Apparatus as recited in claims 1 or 2, wherein said means for detecting is an array of Schottky barrier detectors selected from the group of platinum silicide and paladium silicide detectors.

14. Apparatus as recited in claim 13, wherein said means for imaging is an array of PtSi Schottky barrier detectors.

15. Apparatus as recited in claims 1 or 2, wherein said means for tracking operates with pulse widths from 1 nanosecond to 1000 nanoseconds.

16. Apparatus as recited in claim 15, wherein said imaging array operates in the range of 1 frame/second to 1000 frames/second.

17. Apparatus as recited in claims 1 or 2, wherein said tracking array operates at about real time and said imaging array operates at about 30 frames/second.

18. Apparatus as recited in claims 1 or 2, wherein said tracking array substantially covers part of the field of view of said imaging array.

19. Apparatus as recited in claims 1 or 2, wherein said means for tracking is in the range from full field of view to a 2×

2 quad cell and said imaging array is about a 256×

244 to 5000×

5000 array.

20. Apparatus as recited in claims 1 or 2, wherein signals from said means for tracking are amplified in a low-noise amplifier.

21. Apparatus as recited in claims 1 or 2, wherein elements of the means for detecting are offset from elements of the means for imaging.

22. Apparatus as recited in claims 1 or 2, wherein said means for detecting and said means for imaging are mounted on a structure selected from the group of an aircraft, a satellite, and a missile, and the target is a navigation target.

2. Apparatus for imaging a target comprising:

(a) means for detecting light reflected from the target, said means for detecting operating at a rate selected from the group of a high frame rate and real time; and

(b) means for imaging the target, said means for imaging having one or more operational parameters adjusted in response to the output of said means for detecting.

12. Apparatus as recited in claim 2, wherein said operational parameter is selected from the group of frame rate, gain, black level, dynamic range, time of start integration, integration time, exposure control, field of view, and position of the means for imaging.

23. A semiconductor device for detecting and imaging a target comprising:

(a) a first array of Schottky diodes, said first array being a high resolution array;

(b) a second Schottky diode array mounted in a plane displaced from said first Schottky diode array, said second Schottky diode array having a resolution different from said first array; and

(c) means for controlling said first array upon detection of target by said second array.

24. The semiconductor device as recited in claim 23, wherein the first array is a 2×

2 quad cell and said second array is a 488×

512 element array.

25. The semiconductor device as recited in claim 23, wherein elements of the second array are located between the first array and an object to be imaged.

26. The semiconductor device as recited in claim 25, further comprising a lens, said lens located between the object to be imaged and the second array, said lens projecting light having a wavelength of about 1.06 μ

m on said second array and light having a wavelength in the range of 3-5 μ

m on said second array.

27. The semiconductor device as recited in claim 24, wherein said second array is selected from the group metal barrier Schottky barrier diodes, PtSi, Pd₂ Si, IrSi Schottky barrier arrays, and combinations thereof.

28. The semiconductor device as recited in claim 24, wherein said first array is an imaging array.

29. The semiconductor device as recited in claim 26 further comprising a 3-5 μ

m filter between said first and said second array, said filter 1.06 μ

m radiation to said first array whereby the filter reacting acts as a dielectric mirror.

30. The semiconductor device as recited in claim 24 further comprising a liquid nitrogen bath for maintaining said first and said second array at substantially 80°

K. or below.

31. Apparatus as recited in claim 24 further comprising a control system, said control system adjusting an operational parameter of said first array based on input from said second array, said operational parameter selected from the group of gain, frame rate, black level, dynamic range, start integration time, exposure control, field of view, and position of the means for imaging.

32. Apparatus as recited in claim 23 further comprising metal gratings on elements of said second array.

33. Apparatus as recited in claim 32, wherein said gratings are aluminum and N+ gratings.

34. Apparatus as recited in claim 23, wherein a depletion layer of a detector in said first array protrudes through a substrate of the detector.

35. A semiconductor device for detecting and imaging a target comprising:

(a) a first array of Schottky diodes, said first array being high resolution array; and

(b) a second Schottky diode array mounted in a plane displaced from said first Schottky diode array, said second Schottky diode array having a resolution different from said first array, wherein the second array operates in the range from real time or at a frame rate in the range from 30 to 10,000 frames per second and said first array operates in the range from one frame per second to 2,000 frames per second.

36. Apparatus as recited in claim 35 further comprising a first multiplexer for processing signals from said first array and a second multiplexer for processing signals from said second array.

37. A semiconductor device for detecting and imaging a target comprising:

(a) a first array of Schottky diodes, said first array being a high resolution array; and

(b) a second Schottky diode array mounted in a plane displaced from said first Schottky diode array, said second Schottky diode array having a resolution different from said first array, wherein elements of the second array are located between the first array and an object to be imaged, and wherein elements of the second array lie outside of array path of light from the object to be imaged to the first array.

38. The semiconductor device as recited in claim 37, wherein said second array is a PtSi Schottky diode array.

39. A semiconductor device for detecting and imaging a target comprising:

(a) a first array of Schottky diodes, said first array being a high resolution array; and

(b) a second Schottky diode array mounted in a plane displaced from said first Schottky diode array, said second Schottky diode array having a resolution different from said first array, further comprising means for activating said first array upon detection of a target by said second array.

40. A kit for detecting and imaging a target comprising:

(a) means for transmitting coded light to a target of interest;

(b) a first Schottky diode array for detecting said coded, coherent light, said first Schottky diode array being a low resolution Schottky diode array selected from the group platinum, paladium, and iridium;

(c) a second Schottky diode array adapted to be positioned such that said first array is between the target and the second array, said second Schottky diode array having a resolution different than said first array and comprising a Schottky diode array;

(d) a lens for focusing said coherent light on said first array and thermal infrared light on said second array;

(e) a first multiplexer and a low noise amplifier for processing signals from said first array;

(f) a second multiplexer for processing signals from said second array; and

(g) means response to a signal from said first array for affecting the operation of said second array.

41. Apparatus for imaging a target comprising:

(a) means for detecting light reflected from the target, said means for detecting operating at a rate selected from the group of a high frame rate and real time; and

(b) means for imaging the target, said means for imaging having an operational parameter adjusted by said means for detecting, wherein said means for imaging is activated upon detection of a target by said means for detecting.

42. Apparatus for detecting and imaging a target comprising:

(a) means for detecting light reflected from the target, said means for detecting comprising a low angular resolution array; and

(b) means for imaging a target detected by the means for detecting, said means for imaging comprising a higher angular resolution array, wherein said means for imaging is activated upon detection of a target by said means for detecting.