Solid state electronic camera including thin film matrix of photosensors

• US 4,788,594 A
• Filed: 10/15/1986
• Issued: 11/29/1988
• Est. Priority Date: 10/15/1986
• Status: Expired due to Term

• Current Assignee: Energy Conversion Devices
• Original Assignee: Energy Conversion Devices
• Inventors: Norris, Lawrence G., Ovshinsky, Stanford R.
• Primary Examiner(s): Ng, Jin F.
• Assistant Examiner(s): BRINICH, STEPHEN M
• Application Number:
  US06/918,952
• Time in Patent Office: 776 Days
• Field of Search: 358/294, 358/213.11, 358/213.23, 358/213.27, 358/213.28, 358/213.31, 358/909, 358/213.13, 250/578
• US Class Current: 348/64
• CPC Class Codes: H01L 27/14665 Imagers using a photoconductor layer
• CPC Class Codes: H04N 23/00 Cameras or camera modules comprising electronic image sensors; Control thereof
• CPC Class Codes: H04N 25/00 Circuitry of solid-state image sensors [SSIS]; Control thereof

Abstract

A thin film photosensor array for an electronic camera, said array adapted to provide an electrical signal corresponding to an image projected thereon. The photosensor array is preferably fabricated as a large area matrix of thin film, small area photosensitive elements capable of providing high resolution output in response to input from conventional camera optical systems. The photosensor array can be specifically tailored to provide color output or particular spectral sensitivity.

Claims

1. An electronic camera including:

a thin film photosensor array adapted to read a pattern of information incident thereon and generate a detectable electrical signal corresponding thereto;

means adapted to optically project a pattern of information corresponding to an object onto said photosensor array;

means for triggering the reading of the pattern of information projected onto said photosensor array and

said array including a plurality of small area photoresponsive elements, each of said elements adapted to photogenerate an electrical signal in response to the illumination thereof and including at least one layer of a semiconductor alloy material chosen from the group consisting of;

amorphous silicon alloy materials, amorphous germanium alloy materials, and amorphous silicon carbon alloy materials or amorphous silicon germanium alloy materials.

2. A camera as in claim 1, wherein said plurality of photoresponsive elements are chosen from the group consisting essentially of:

photodiodes, phototransistors, photoresistors, photovoltaic devices, or combination thereof.

3. An electronic camera as in claim 2, wherein each of said photoresponsive elements is a photodiode which includes two oppositely doped layers of semiconductor material.

4. A camera as in claim 3, wherein each photodiode further includes a layer of substantially intrinsic semiconductor material interposed between said oppositely doped layers so as to form a p-i-n type photodiode.

5. A camera as in claim 1, wherein said thin film photosensor array further includes addressing means for accessing each of the plurality of photoresponsive elements.

6. A camera as in claim 5, wherein said addressing means includes a plurality of electrically conductive lines arranged so as to form an x-y matrix.

7. A camera as in claim 6, wherein said addressing means further includes a current blocking element associated with each photoresponsive element, said blocking element and said address lines cooperating to provide electrical communication with preselected ones of said photoresponsive elements.

8. A camera as in claim 7, wherein said blocking elements are chosen from the group consisting of diodes, transistors, resistors, threshold switches, relays, or combinations thereof.

9. A camera as in claim 7, wherein each of said blocking elements is a p-i-n type diode.

10. A camera as in claim 1, wherein said thin film photosensor array is fabricated as a rectangular matrix having sides dimensioned to be at least 35 mm.

11. A camera as in claim 10, wherein the image resolution of said photosensor array is at least 20 lines/mm.

12. A camera as in claim 1, wherein said photosensor array is fabricated as a rectangular matrix having sides dimensioned to be at least 5.7 cm on an edge and including at least 1.4 million discrete photoresponsive elements.

13. A camera as in claim 1, wherein said array includes at least two groups of photoresponsive elements, each group sensitive to a different portion of the electromagnetic spectrum, said groups cooperating to provide an electrical signal corresponding to the color values of the image projected thereonto.

14. A camera as in claim 13, wherein each of said groups of photoresponsive elements includes an optical filter for providing said sensitivity to different portions of the electromagnetic spectrum.

15. A camera as in claim 13, wherein each group of photoresponsive elements is fabricated with a photogenerative region formed from a semiconductor material having a band gap optimized to provide said sensitivity to different wavelengths of the electromagnetic spectrum.

16. A camera as in claim 1, wherein said thin film photosensor array is a two dimensional matrix.

17. A camera as in claim 1, wherein said thin film photosensor array is linear.

18. A camera as in claim 1, wherein said optical projecting means includes at least one lens.

19. A camera as in claim 1, wherein said read triggering means comprises mechanical means adapted to initiate the reading of said pattern of information.

20. A camera as in claim 19, wherein said mechanical means includes a shutter.

21. A camera as in claim 1, wherein said read triggering means comprises electrical means adapted to initiate reading or storage of said pattern of information.

22. A camera as in claim 21, wherein said electrical means includes address circuitry for accessing said photosensor array.

23. A camera as in claim 22, wherein at least a portion of said address circuitry is integrated on a single substrate with said photosensor array.

24. A camera as in claim 1, wherein said optical means further includes means for controlling the intensity of said image projected onto the photosensor array.

25. A camera as in claim 1, wherein said photosensor array is detachably mounted in the camera at the focal plane of said optical means.

26. A camera as in claim 1, wherein said photosensor array forms a portion of the back of said camera.

27. A camera as in claim 1, further including a video display terminal adapted to receive the electrical signal corresponding to the projected pattern and provide a visual display thereof.

28. A camera as in claim 1, further including printer means adapted to receive the electrical signal corresponding to the pattern projected onto the photosensor array and provide a hard copy, visual representation thereof.

29. A camera as in claim 1, further including storage means for storing the electrical signal generated by the photosensor array.

30. A camera as in claim 1, further including means for electronically processing the electrical signal generated by the photosensor array.

31. A camera as in claim 1, further including a chemical photographic medium therein, wherein said electrical signal generated by the array controls the exposure of the chemical photographic medium.