Hybrid imaging sensor with shared readout

A pixel circuit, comprising:

• a pixel array including a plurality of pixels arranged in rows and columns, wherein each pixel includes:
• a photodiode configured to photogenerate image charge in response to incident light;
• and
• a transfer transistor coupled to the photodiode to transfer the image charge out from the photodiode;
• and
• a color filter array disposed over the pixel array, wherein the color filter array includes a plurality of color filters each having one of a plurality of colors and disposed over at least one of the plurality of pixels,
• wherein
• each of the plurality of pixels is coupled to a first readout circuit,
• the plurality of pixels includes (i) a first subset of pixels of the plurality of pixels and (i) a second subset of pixels of the plurality of pixels, the second subset of pixels being coupled to a second readout circuit,
• two diagonally arranged pixels are coupled together to share a floating diffusion,
• the two diagonally arranged pixels coupled together are disposed underneath color filters of a same color, and
• the color filter array comprises a quad color filter array formed of red color filters, green color filters, blue color filters, and clear filters arranged in a manner such that in each 2×2 grouping of pixels
• color filters of a same color are disposed over a first pair of diagonally arranged pixels included in the first subset of pixels, wherein the first pair of pixels share a floating diffusion, and wherein the same color is red, blue, or green, and
• clear filters are disposed over a second pair of diagonally arranged pixels included in the second subset of pixels, wherein each pixel of the second pair of diagonally arranged pixels has a separate floating diffusions that is shared with a respective pixel, in a different row that is outside of the 2×2 grouping of pixels.

An imaging system, comprising:

• a pixel circuit including:
• a pixel array having a plurality of pixels arranged in rows and columns, wherein the plurality of pixels includes a first subset of the pixels and a second subset of the pixels, and wherein each of the plurality of pixels includes:
• a photodiode configured to photogenerate image charge in response to incident light;
• and
• a transfer transistor coupled to the photodiode to transfer the image charge out from the photodiode;
• and
• a color filter array disposed over the pixel array, wherein the color filter array includes a plurality of color filters each having one of a plurality of colors and disposed over at least one of the pixels;
• a first readout circuit coupled to each of the plurality of pixels such that each of the plurality of pixels is configurable to read out a first set of data signals to the first readout circuit;
• a second readout circuit coupled to each of the pixels included in the second subset such that each of the pixels included in the second subset is configurable to read out a second set of data signals to the second readout circuit, wherein the second set of data signals is different from the first set of data signals, and wherein each of the pixels included in the first subset is not configurable to output the second set of data signals to the second readout circuit;
• and
• a mode select switch circuit coupled to the pixels included in the second subset, wherein the pixels included in the second subset are configured to provide either the first set of data signals to the first readout circuit or the second set of data signals to the second readout circuit in response to the mode select circuit,
• wherein two diagonally arranged pixels are coupled together to share a floating diffusion, and
• wherein the two diagonally arranged pixels coupled together are disposed underneath color filters of a same color.