SOLID STATE INTEGRATING, IMAGE MOTION COMPENSATING IMAGER

• US 3,833,762 A
• Filed: 06/04/1973
• Issued: 09/03/1974
• Est. Priority Date: 06/04/1973
• Status: Expired due to Term

• Current Assignee: Richard A. Gudmundsen
• Original Assignee: Richard A. Gudmundsen
• Inventors: Gudmundsen, Richard A.
• Primary Examiner(s): Richardson, Robert L.
• Application Number:
  US05/366,828
• Time in Patent Office: 456 Days
• Field of Search: 178/7.1,7.2,DIG.40 250/578,211J,211R 317/235N
• US Class Current: 348/208.99
• CPC Class Codes: H04N 25/71 Charge-coupled device [CCD] sensors; Charge-transfer registers specially adapted for CCD sensors
• CPC Class Codes: H04N 25/72 using frame transfer [FT]

Abstract

An integrating image motion compensator is disclosed. The compensator comprises photo-responsive charge transfer means, overlying transparent insulation means and transparent charge transfer electrode means spaced from the charge transfer means by the insulation means. Channel isolation means associated with the charge transfer means define individual charge transfer channels. The operating system further comprises means for inducing separate charge collection regions within each channel and for transferring the regions along the charge transfer means at a controllable rate. Image speed sensing means sense the image speed and synchronize the rate of charge transfer with the rate of image movement. When large area image motion compensators are needed, optical image segmentation means are provided to allow the use of many small compensators to form a composite, large, image motion compensator. In the preferred embodiment the photoresponsive charge transfer means is a semiconductor layer having a gap energy less than the energy of the photons forming the image to be converted. A plurality of parallel charge transfer channels are defined at the surface of the semiconductor by stripes of heavily doped semiconductor material which isolates the channels. The transparent control electrodes are preferably divided into four sets to form a four-phase charge transfer control system. The photons comprising the image to be converted are incident on the semiconductor through the overlying transparent insulator and electrodes. Potential wells within the charge transfer channels are stepped along the channels at the same rate at which the image is traveling along the channel. Thus, all the photons arriving from a given image point strike in the same potential well and contribute to the charge therein. At the end of the transfer channel, any charge therein is sensed in any appropriate manner, such as by a back-biased pn junction. Non-transparent control electrodes may be employed if a thin semiconductor chip is used, and the light is focused onto the back surface of the device.

Claims

1. An integrating image motion compensator comprising:

photo-responsive charge transfer means, having an upper surface;

overlying transparent insulation means; and

transparent charge transfer electrode means, spaced from the charge transfer means by the insulation means.

2. The apparatus of claim 1 further comprising readout means for sensing the charge in a charge collecting region.

3. The apparatus of claim 2 further comprising channel isolation means defining a plurality of parallel charge transfer channels within the charge transfer means.

4. The apparatus of claim 3 further comprising means for inducing separate charge collecting regions within the charge transfer means and for transferring the regions along the charge transfer means at a controllable rate.

5. An integrating image motion compensator comprising:

photo-responsive charge transfer means, having an upper surface;

overlying insulation means;

charge transfer electrode means spaced from the charge transfer means by the insulation means;

readout means for sensing the charge in the charge transfer means.

6. The apparatus of claim 5 further comprising channel isolation means defining a plurality of parallel charge transfer channels within the charge transfer means.

7. The apparatus of claim 6 further comprising means for inducing a plurality of separate charge collecting regions within each of the charge transfer channels and for transferring the regions along the charge transfer channels at a controllable rate.

8. The apparatus of claim 7 further comprising:

synchronization means for synchronizing the charge collecting region transfer rate with the rate of motion along the charge transfer means of an image focused thereon, whereby the same charge collection region travels with an image point throughout its movement along the charge transfer means.

9. The apparatus of claim 8 further comprising:

orientation means for aligning the charge transfer channel means with the direction of movement of the image, whereby a given image point travels along one of the plurality of channels defined within the charge transfer means.

10. The apparatus of claim 6 wherein the charge transfer electrode means comprises a plurality of parallel electrodes oriented at an angle with respect to the individual channels.

11. The apparatus of claim 10 wherein the charge transfer channel means comprises a semiconductor layer.

12. The apparatus of claim 11 wherein:

the isolation means is associated with the upper surface of the semiconductor layer;

13. The apparatus of claim 12 wherein the semiconductor layer is of a first conductivity type and the channel isolation means comprise semiconductor regions of the first conductivity type which are more heavily doped than the main semiconductor layer.

14. The apparatus of claim 10 wherein the electrodes are divided into first, second, third, and fourth electrode sets, each set being comprised of every fourth electrode and wherein each first electrode is adjacent one fourth electrode and one second electrode, each second electrode is adjacent one first electrode and one third electrode, each third electrode is adjacent one second electrode and one fourth electrode, and each fourth electrode is adjacent one third electrode and one first electrode, excepting only the end electrodes each of which is adjacent only one of the two specified electrodes.

15. The apparatus of claim 14 wherein adjacent electrodes are spaced apart vertically by the insulation means, but overlap horizontally to insure that potential wells induced by adjacent electrode are continuous.

16. An integrating image motion compensator comprising:

a layer of semiconductor material of a first conductivity type having length, breadth, depth and an upper surface;

a plurality of elongated semiconductor channel isolation regions of the first conductivity type associated with the upper surface of the semiconductor, said isolation regions being more heavily doped than the layer of semiconductor material;

an insulating layer overlying the semiconductor material;

a plurality of parallel electrodes oriented substantially perpendicular to the channel isolation regions, said electrodes being disposed in first and second parallel planes, spaced from the semiconductor and each other by the insulating layer, every other electrode along the length of the semiconductor layer being in the first plane and the alternate electrodes being in the second plane, each electrode other than the two end electrodes overlapping the two adjacent electrodes in the other plane.

17. A large field of view image motion compensating system comprising:

a plurality of integrating image motion compensators, each comprising;

photoresponsive charge transfer means, having an upper surface;

overlying insulation means;

charge transfer electrode means spaced from the charge transfer means by the insulation means;

channel isolation means defining a plurality of parallel charge transfer channels within the charge transfer means;

readout means for sensing the charge in a channel at a readout location;

optical field of view segmenting means for dividing a continuous field of view into a plurality of spacially separated segments, different image segments being focused on different integrating image motion compensators, whereby the combined output of all of the compensators constitutes a conversion of an image extending over more than one compensator.

18. The system of claim 17 further comprising means for inducing a plurality of separate charge collecting regions within the charge transfer channels of the image motion compensators and for transferring the charge collecting regions along the charge transfer channels at a controllable rate.

19. The apparatus of claim 18 further comprising:

synchronization means for synchronizing the charge collecting region transfer rate with the rate of motion along the charge transfer means of an image focused thereon, whereby the same charge collection region travels with an image point throughout its movement along the charge transfer means of a given image motion compensator.

20. The apparatus of claim 19 further comprising:

orientation means for orienting the image motion compensators with their charge transfer channels aligned with the direction of movement of the image, whereby a given image point travels along one of the plurality of channels of an image motion compensator.

21. A method of operating an integrating image motion compensator which comprises photoresponsive charge transfer means and control means therefor, said method comprising the steps of:

focusing an image to be converted onto the compensator;

inducing separate charge collecting regions within the charge transfer channel means;

transferring the charge collecting regions along the channel means; and

sensing the charge in the charge transfer channel means at an output point.

22. The method of claim 21 further comprising the step of:

synchronizing the charge collecting region transfer rate with the rate of movement of the image acrOss the image motion compensator.

23. The method of claim 21 further comprising the steps of:

sensing the rate of movement of the image across the image motion compensator;

synchronizing the charge collecting region transfer rate with the rate of movement of the image across the image motion compensator.

24. The method of claim 23 further comprising the step of:

aligning the individual charge transfer channels parallel to the direction of image motion.