Color pattern and pixel level binning for APS image sensor using 2×2 photodiode sharing scheme
First Claim
1. A color image sensor comprising:
- a sensor circuit including an array of photodetectors arranged in rows and columns; and
a color filter mosaic including individual filter elements that are superposed in one-to-one registry over said plurality of photodetectors, said mosaic being comprised of a first type of filter element having a first luminance transparency characteristic, a second type of filter element having a second transparency characteristic different from that of said first luminance transparency characteristic, and a third type of filter element having a third transparency characteristic different from that of said first and second luminance transparency characteristics,wherein the filter elements are arranged in repeating patterns such that;
the first type of filter element is present over every other said photodetector in each row and column, whereby a first group of the first type of filter element forms a first diagonal line comprising only said first type of filter element, andthe second and third types of color filters are arranged in repeating patterns such that the second and third types of filter element are present over every fourth said photodetector in each row and column, whereby a second group of said second type of filter elements forms a second diagonal line comprising only said second type of filter element, and whereby a third group of said third type of filter elements forms a third diagonal line comprising only said third type of filter element,wherein the sensor circuit further comprises;
a plurality of floating diffusions, each floating diffusion being coupled to a first photodetector by a first transfer gate, a second photodetector by a second transfer gate, a third photodetector by a third transfer gate, and a fourth photodetector by a fourth transfer gate, the first, second, third and fourth photodetectors being included in said array of photodetectors with the first and second photodetectors being disposed in a first row of the array, and the third and fourth photodetectors being disposed in a second row of the array, andmeans for simultaneously transferring both a first charge present in the first photodetector and a second charge present in the fourth photodetector to said floating diffusion during a first time period, and for simultaneously transferring both a third charge present in the second photodetector and a fourth charge present in the third photodetector to said floating diffusion during a second time period.
1 Assignment
0 Petitions
Accused Products
Abstract
A color image sensor includes an array of pixels arranged in a plurality of pixel groups, each pixel group including a floating diffusion that is shared by four pixels disposed in a 2×2 arrangement. Each of said four pixels includes a photodetector and a color filter superposed over the photodetector, wherein a first pair of said four pixels include green color, and a second pair of said four pixels includes either red or blue color filters. A control circuit controls the pixel groups such that discrete image information is generated from each pixel in normal light situations, and such that summed image information is generated from each pixel group in low light situations by simultaneously connecting the green pixels to the floating diffusion during a first time period, and simultaneously connecting the red/blue pixels to said floating diffusion during a second time period.
-
Citations
18 Claims
-
1. A color image sensor comprising:
-
a sensor circuit including an array of photodetectors arranged in rows and columns; and a color filter mosaic including individual filter elements that are superposed in one-to-one registry over said plurality of photodetectors, said mosaic being comprised of a first type of filter element having a first luminance transparency characteristic, a second type of filter element having a second transparency characteristic different from that of said first luminance transparency characteristic, and a third type of filter element having a third transparency characteristic different from that of said first and second luminance transparency characteristics, wherein the filter elements are arranged in repeating patterns such that; the first type of filter element is present over every other said photodetector in each row and column, whereby a first group of the first type of filter element forms a first diagonal line comprising only said first type of filter element, and the second and third types of color filters are arranged in repeating patterns such that the second and third types of filter element are present over every fourth said photodetector in each row and column, whereby a second group of said second type of filter elements forms a second diagonal line comprising only said second type of filter element, and whereby a third group of said third type of filter elements forms a third diagonal line comprising only said third type of filter element, wherein the sensor circuit further comprises; a plurality of floating diffusions, each floating diffusion being coupled to a first photodetector by a first transfer gate, a second photodetector by a second transfer gate, a third photodetector by a third transfer gate, and a fourth photodetector by a fourth transfer gate, the first, second, third and fourth photodetectors being included in said array of photodetectors with the first and second photodetectors being disposed in a first row of the array, and the third and fourth photodetectors being disposed in a second row of the array, and means for simultaneously transferring both a first charge present in the first photodetector and a second charge present in the fourth photodetector to said floating diffusion during a first time period, and for simultaneously transferring both a third charge present in the second photodetector and a fourth charge present in the third photodetector to said floating diffusion during a second time period. - View Dependent Claims (2, 3, 4, 5)
-
-
6. A color image sensor comprising:
-
an array of photodetectors arranged in pixel groups on a substrate, each pixel group comprising; a floating diffusion; and first, second, third and fourth photodetectors respectively coupled to the floating diffusion by first, second, third and fourth transfer gates, wherein the first and second photodetectors are disposed in a first row of the array, the third and fourth photodetectors are disposed in a second row of the array, the first and third photodetectors disposed in a first column of the array, and the second and fourth photodetectors disposed in a second column of the array, a color filter mosaic including individual filter elements that are superposed in one-to-one registry over said array of photodetectors, said mosaic being comprised of a first type of filter element having a first luminance transparency characteristic, a second type of filter element having a second transparency characteristic different from that of said first luminance transparency characteristic, and a third type of filter element having a third transparency characteristic different from that of said first and second luminance transparency characteristics, wherein both a first color filter superposed over said first photodetector of each pixel group and a second color filter superposed over the fourth photodetector of said each group comprise the first type of filter element, and wherein both a third color filter superposed over the second photodetector and a fourth color filter superposed over the third photodetector comprise one of the second type and the third type of filter element, and means for simultaneously transferring both a first charge present in the first photodetector and a second charge present in the fourth photodetector of a selected pixel group to said floating diffusion during a first time period, and for simultaneously transferring both a third charge present in the second photodetector and a fourth charge present in the third photodetector of said selected pixel group to said floating diffusion during a second time period. - View Dependent Claims (7, 8, 9, 10, 11, 12)
-
-
13. A color image sensor comprising:
-
an array of pixels arranged in a plurality of pixel groups, each pixel group including a floating diffusion and four pixels disposed in a 2×
2 arrangement, each of said four pixels including a photodetector, a transfer gate connected between said photodetector and said floating diffusion, and a color filter superposed over said photodetector, wherein a first pair of said four pixels include color filters of a first type having a first luminance transparency characteristic, and a second pair of said four pixels include color filters having one of a second type and a third type, the second type having a second luminance transparency characteristic different from that of said first luminance transparency characteristic, and the third type having a third transparency characteristic different from that of said first and second luminance transparency characteristics; andmeans for determining an image signal strength received by said array of pixels; means for generating discrete image information from each of said four pixels of a selected pixel group by sequentially connecting each of said four pixels to said floating diffusion of said selected pixel group when the determined image signal strength is above a predetermined minimum signal value; and means for generating summed image information from said four pixels of the selected pixel group by simultaneously connecting the first pair of said four pixels to said floating diffusion during a first time period, and simultaneously connecting the second pair of said four pixels to said floating diffusion during a second time period different from the first time period when the determined image signal strength is below the predetermined minimum signal value. - View Dependent Claims (14, 15, 16, 17, 18)
-
Specification