Image sensors with on-chip ADC data compression for multi-bit electron-number outputs

A system, comprising:

• one or more lenses;
• and
• an image sensor configured to receive light that has passed through the lenses to reach the image sensor, comprising:
• a plurality of pixels configured to generate analog signals corresponding to a digital image based on photoelectrons accumulated by the pixels when exposed to the light;
• one or more analog-to-digital conversion circuits configured to convert the analog signals to digital signals of the digital image, wherein the digital signals include (a) a first set of digital signals of the digital image individually having a value corresponding to an integer number of discrete photoelectrons and (b) a second set of digital signals of the digital image individually having a value between values of the first set of digital signals so as to correspond to a non-integer number of discrete photoelectron;
• and
• a quantization circuit configured to convert the second set of digital signals to a third set of digital signals of the digital image, wherein the third set of digital signals individually has a value corresponding to an integer number of discrete photoelectrons.

A device, comprising:

• a camera, comprising:
• one or more lenses;
• and
• an image sensor configured to receive light that has passed through the lenses to reach the image sensor, comprising:
• a plurality of pixels configured to generate analog signals corresponding to a digital image based on photoelectrons accumulated by the pixels when exposed to the light;
• one or more analog-to-digital conversion circuits configured to convert the analog signals to digital signals of the digital image, wherein the digital signals include (a) a first set of digital signals of the digital image individually having a value corresponding to an integer number of discrete photoelectrons and (b) a second set of digital signals of the digital image individually having a value between values of the first set of digital signals so as to correspond to a non-integer number of discrete photoelectron;
• and
• a quantization circuit configured to convert the second set of digital signals to a third set of digital signals of the digital image, wherein the third set of digital signals individually has a value corresponding to an integer number of discrete photoelectrons;
• and
• an image signal processor configured to process the first set of digital signals and the third set of digital signals to generate one or more images.