Abstract There is disclosed a linear solid-state photosensor which exhibits avalanche multiplication and which has a resolution capability comparable to that of silver halide photography. The photosensor is of the type which is suitable for use in a slit image camera of the type commonly carried by airplanes, satellites, or any other moving vehicle which can position the image forming slit so that the scene to be photographed passes by it. In this event, of course, the movement of the scene relative to the camera replaces the more conventional movement of the film relative to the camera''s optical axis. The photosensor of this invention replaces the film of the camera in such applications and is capable of providing a direct conversion of the light image to electrical signal output in a manner analogous to that of a television camera. There is also disclosed herein a method of manufacturing the linear solid-state photosensor so as to achieve the desired resolution.
Apparatus as in claim 1 wherein an integrating capacitor is formed in parallel circuit relationship with the other one of the rectifying junctions of each said pair of junctions
Claim 2
Dependent Claim
172 words
In combination comprising: a plurality of pairs of photosensitive diodes positioned adjacent to each other in linear sequential relationship to form an elongated image sensing element, the diodes of each pair being connected in an electric series circuit relationship and all of the pairs of diodes being connected in electric parallel circuit relationship; means for applying an input voltage across said parallel circuit; the first diode in each of said pairs being positioned immediately adjacent to and coaligned with a corresponding diode in a succeeding adjacent one of said pairs so as to receive a linear segment of an optical image falling thereon, said first diodes each being reverse biased; a second diode in each of said pairs being positioned immediately adjacent to a second diode in another of said pairs to form a linear switching segment, said second diodes each being reverse biased; and an optical scanning means for scanning said linear switching segment to read out from each of said pairs of diodes the intensity of light in said image.
Claim 3
Dependent Claim
34 words
The combination set forth in claim 14 wherein said diodes comprise an integrated circuit formed in a semiconductor substrate, said integrated circuit having at least 5,000 diodes per linear inch of said sensing element.
Claim 4
Dependent Claim
21 words
The combination set forth in claim 3 wherein each of said first diodes has an integrating capacitor connected in parallel therewith.