Image sensor including avalanche photodiode

An image sensor comprising:

• a pixel array including a plurality of pixels each including an avalanche photodiode;
• a data accumulator configured to generate a plurality of subframe images including a first subframe image and a second subframe image by accumulating count values of pixel data from the pixel array for each unit exposure time;
• and
• a signal processor configured to generate a frame image by processing the plurality of subframe images,
• wherein the signal processor is configured to,
• calculate difference vectors for the second subframe image with respect to the first subframe image as a reference, and
• generate a corrected second subframe image by applying the difference vectors to the second subframe image, and generate the frame image by adding the corrected second subframe image to the first subframe image.

An image sensor comprising:

• a pixel array comprising a light-receiving unit including an avalanche photodiode, and a pixel circuit;
• a data accumulator configured to generate a plurality of subframe images by accumulating count values of pixel data from the pixel array for each unit exposure time;
• and
• a signal processor configured to generate a frame image by processing the plurality of subframe images,
• wherein the signal processor is configured to determine an increase or a decrease in a subsequent subframe rate based on a parameter related to difference vectors calculated by comparison between some of the plurality of subframe images.