Optimized hybrid Bayer color filter array
In some embodiments, an image sensor structure receives light from a color filter array that includes multiple regions. A high resolution region includes a first bayer pattern of color filters that filter light for individual sensors of a sensor array while a lower resolution region includes second bayer pattern of color filters that filter light for groups of sensors of the sensor array. Images may be read from the image sensor in multiple resolutions, with images read in a highest resolution mode preserving maximum detail while images read in lower resolution modes may requires less hardware and computational resources and may exhibit better noise performance, in some embodiments. Various regions of the image sensor structure may correspond to different modes of operation or differing resolving capabilities of a corresponding lens assembly for the image sensor structure.
1 . A camera module, comprising:
a lens assembly with a variable focal length;
a color filter array comprising a plurality of non-overlapping regions, including a first region and a second region, configured to filter light received at a plurality of sensors, wherein the first region and the second region comprise respective color filter patterns comprising a plurality of color filters arranged in an equal number of rows and columns, and wherein at least a portion of the color filters of individual patterns of the color filter patterns are different from other color filters of the individual patterns;
the first region comprising one or more repetitions of a first color filter pattern, wherein individual repetitions of the one or more repetitions of the first color filter pattern filter light received at a first number of sensors; and
the second region comprising one or more repetitions of a second color filter pattern, wherein individual repetitions of the one or more repetitions of the second color filter pattern filter light received at a second number of sensors, wherein the second number of sensors is different from the first number of sensors;
wherein the first region corresponds to a first image circle of a telephoto range of the variable focal length of the lens assembly;
wherein the second region corresponds to a second image circle of a wide angle range of the variable focal length of the lens assembly; and
wherein the second number of sensors is greater than the first number of sensors.
2 . The camera module of claim 1 , wherein the color filter pattern is a Bayer filter pattern, and wherein the camera module further comprises a demosaic subsystem configured to derive full color pixel data from respective Bayer pattern color filter tiles.
3 . The camera module of claim 2 , further comprising an analog to digital converter (ADC) configured to convert analog signals received from individual ones of the plurality of sensors to a plurality of digital pixel values, wherein at least a portion of the plurality of digital pixel values corresponding to sensors receiving filtered light from a lower resolution region of the plurality of non-overlapping regions comprises individual pixel values respectively converted based on the analog signals of a plurality of sensors.
4 . The camera module of claim 3 , wherein individual pixel values corresponding to the lower resolution region are respectively converted using analog signals from individual sensors and are contiguous to at least one other individual pixel value of the same Bayer pattern color, and wherein the demosaic subsystem is further configured to derive full color pixel data from a Bayer pattern comprising individual pixel values contiguous to other individual pixel values of the same Bayer pattern color.
5 . The camera module of claim 3 , wherein individual pixel values corresponding to the lower resolution region are respectively converted from a digital sum of respective ADC conversions of individual ones of a plurality of analog signals from respective sensors.
6 . The camera module of claim 3 , wherein individual pixel values corresponding to the lower resolution region are respectively converted from an analog average of a plurality of analog signals from respective sensors.
7 . The camera module of claim 3 , wherein individual ones of a plurality of sensors receiving light from a particular color filter of the lower resolution region share a floating diffusion node.
8 . An image sensor assembly, comprising:
a lens assembly with a variable focal length;
a color filter array comprising a plurality of non-overlapping regions, including a first region and a second region, configured to filter light received at a plurality of sensors, wherein the first region and the second region comprise color filter patterns further comprising a plurality of color filters arranged in an equal number of rows and columns, and wherein at least a portion of the color filters of individual patterns of the color filter patterns are different from other color filters of the individual patterns;
the first region corresponding to a first image region of a telephoto range of a variable focal length lens and comprising one or more repetitions of a first color filter pattern, wherein individual repetitions of the one or more repetitions of the first color filter pattern filter light received at a first number of sensors; and
the second region corresponding to a second image region of a wide angle range of the variable focal length lens and comprising one or more repetitions of a second color filter pattern, wherein individual repetitions of the one or more repetitions of the second color filter pattern filter light received at a second number of sensors, wherein the second number of sensors is different from the first number of sensors;
wherein the first region corresponds to a first image circle of a telephoto range of the variable focal length of the lens assembly;
wherein the second region corresponds to a second image circle of a wide angle range of the variable focal length of the lens assembly; and
wherein the second number of sensors is greater than the first number of sensors.
9 . The image sensor array of claim 8 , wherein the color filter array is organized according to a Bayer filter pattern, and wherein the camera module further comprises a demosaic subsystem configured to derive full color pixel data from respective Bayer pattern color filter tiles.
10 . The image sensor array of claim 9 , further comprising:
an analog to digital converter (ADC) configured to convert analog signals received from individual ones of the plurality of sensors to a plurality of digital pixel values, wherein at least a portion of the plurality of digital pixel values corresponding to sensors receiving filtered light from a lower resolution region of the plurality of non-overlapping regions comprises individual pixel values respectively converted based on the analog signals of a plurality of sensors.
11 . The image sensor array of claim 10 , wherein individual pixel values corresponding to the lower resolution region are respectively converted using analog signals from individual sensors and are contiguous to at least one other individual pixel value of the same Bayer pattern color, and wherein the demosaic subsystem is further configured to derive full color pixel data from a Bayer pattern comprising individual pixel values contiguous to other individual pixel values of the same Bayer pattern color.
12 . The image sensor array of claim 10 , wherein individual pixel values corresponding to the lower resolution region are respectively converted from a digital sum of respective ADC conversions of individual ones of a plurality of analog signals from respective sensors.
13 . The image sensor array of claim 10 , wherein individual pixel values corresponding to the lower resolution region are respectively converted from an analog average of a plurality of analog signals from respective sensors.
14 . The image sensor array of claim 10 , wherein individual ones of a plurality of sensors receiving light from a particular color filter of the lower resolution region share a floating diffusion node.
15 . A method, comprising:
using a lens assembly with a variable focal length to project light onto a color filter array;
filtering light received by a first region of a plurality of non-overlapping regions of the color filter array, wherein the first region comprises one or more repetitions of a first color filter pattern, wherein individual repetitions of the one or more repetitions of the first color filter pattern filter light received at a first number of sensors arranged in an equal number of rows and columns, and wherein at least a portion of the color filters of the first color filter pattern are different from other color filters of the first color filter pattern;
filtering light received by a second region of the plurality of non-overlapping regions of the color filter array, wherein the second region comprises one or more repetitions of a second color filter pattern, wherein individual repetitions of the one or more repetitions of the second color filter pattern filter light received at a second number of sensors arranged in an equal number of rows and columns, and wherein at least a portion of the color filters of the second color filter pattern are different from other color filters of the second color filter pattern, and wherein the second number of sensors is different from the first number of sensors;
wherein the first region corresponds to a first image circle of a telephoto range of the variable focal length of the lens assembly;
wherein the second region corresponds to a second image circle of a wide angle range of the variable focal length of the lens assembly; and
wherein the second number of sensors is greater than the first number of sensors.
16 . The method of claim 15 , wherein the color filter array is organized according to a Bayer filter pattern, and wherein the method further comprises deriving full color pixel data from respective Bayer pattern color filter tiles.
17 . The method of claim 15 , further comprising:
converting analog signals received from individual ones of the plurality of sensors to a plurality of digital pixel values, wherein at least a portion of the plurality of digital pixel values corresponding to sensors receiving filtered light from a lower resolution region of the plurality of non-overlapping regions comprises individual pixel values respectively converted based on the analog signals of a plurality of sensors.
18 . The method of claim 17 , wherein individual pixel values corresponding to the lower resolution region are respectively converted from an analog average of a plurality of analog signals from respective sensors.
19 . The method of claim 17 , wherein individual ones of a plurality of sensors receiving light from a particular color filter of the lower resolution region share a floating diffusion node.