Image sensor having sub-diffraction-limit pixels
An imaging system has an imager comprising a plurality of jots. A readout circuit is in electrical communication with the imager. The readout circuit can be configured to facilitate the formation of an image by defining neighborhoods of the jots, wherein a local density of exposed jots within a neighborhood is used to generate a digital value for a pixel of the image.
1. An imaging integrated-circuit (IC) comprising:
sub-diffraction-limit (SDL) pixels disposed in an array;
color filters disposed in an array and covering respective groups of two or more of the SDL pixels; and
readout circuitry to sample the groups of the SDL pixels following an exposure interval to generate, for each of the groups, digital values having a color association according to color filtration effected by the respective one of the color filters that covers the group.
2. The imaging IC of claim 1 further comprising circuitry to generate a color image based on the digital values generated for each of the groups of the SDL pixels.
3. The imaging IC of claim 1 wherein each of the digital values is a single bit value.
4. The imaging IC of claim 1 wherein, for each of the groups of SDL pixels, each of the digit values contains a single-bit intensity value corresponding to photocharge accumulated within a respective one of the SDL pixels in the group.
5. The imaging IC of claim 1 wherein the color filters comprise red color filters, green color filters and blue color filters.
6. The imaging IC of claim 5 wherein the red color filters, green color filters and blue color filters are disposed in a Bayer filter pattern.
7. The imaging IC of claim 1 wherein the SDL pixels include first and second SDL pixels co-located within a spatial region of the array smaller than or equal to a 3.7 μm-diameter Airy disk.
8. The imaging IC of claim 1 wherein each of the SDL pixels is sized not larger than 0.25 μm 2 .
9. The imaging IC of claim 1 wherein each of the SDL pixels is a complementary metal oxide semiconductor (CMOS) active pixel.
10. The imaging IC of claim 1 wherein the readout circuitry to sample the groups of the SDL pixels following an exposure interval comprises circuitry to sample at least one of the SDL pixels within at least one of the groups prior to conclusion of the exposure interval and upon conclusion of the exposure interval.
11. A method of operation within imaging integrated-circuit (IC) having a plurality of sub-diffraction-limit (SDL) pixels disposed within an array and color filters disposed in an array and covering respective groups of two or more of the SDL pixels, the method comprising:
exposing the SDL pixels to light during an exposure interval; and
sampling the groups of the SDL pixels following the exposure interval to generate, for each of the groups, digital values having a color association according to color filtration effected by the respective one of the color filters that covers the group.
12. The method of claim 11 further comprising generating a color image based on the digital values generated for each of the groups of the SDL pixels.
13. The method of claim 11 wherein each of the digital values is a single bit value.
14. The method of claim 11 wherein, for each of the groups of SDL pixels, each of the digit values contains a single-bit intensity value corresponding to photocharge accumulated within a respective one of the SDL pixels in the group.
15. The method of claim 11 wherein the color filters comprise red color filters, green color filters and blue color filters.
16. The method of claim 15 wherein the red color filters, green color filters and blue color filters are disposed in a Bayer filter pattern.
17. The method of claim 11 wherein the SDL pixels include first and second SDL pixels co-located within a spatial region of the array smaller than or equal to a 3.7 μm-diameter Airy disk.
18. The method of claim 11 wherein each of the SDL pixels is sized not larger than 0.25 μm 2 .
19. The method of claim 11 wherein sampling the groups of the SDL pixels following the exposure interval sampling at least one of the SDL pixels within at least one of the groups prior to conclusion of the exposure interval and upon conclusion of the exposure interval.
20. An imaging integrated-circuit (IC) comprising:
sub-diffraction-limit (SDL) pixels disposed in an array;
color filters disposed in an array and covering respective groups of two or more of the SDL pixels; and
means for sampling the groups of the SDL pixels following an exposure interval to generate, for each of the groups, digital values having a color association according to color filtration effected by the respective one of the color filters that covers the group.