Multiple resolution image sensor

A photooptical sensor comprising:

• an array of pixels, each said pixel including means for providing a pixel signal related to the illumination incident on that pixel;
• and
• reading means coupled to the array for reading out said pixel signals cyclically so that each such reading cycle corresponds to the time interval in which one of said pixel signals is read out from one of said pixels, said reading means being operable to selectively vary the number of pixel signals read out on each such cycle so that on some of said reading cycles a plurality of said pixel signals are read out of said pixels simultaneously, whereas on others of said reading cycles only one of said pixel signals is read out of said pixels, said pixels being arranged in R rows and C columns, said columns extending generally transverse to said rows, where R and C are integers greater than one, said reading means including R row conductors, each said row conductor being associated with the pixels in one of said rows and C column conductors, each said column conductor being associated with the pixels in one of said columns, whereby each said pixel is associated with one said row conductor and one said column conductor, said reading means further including means for selectively energizing said row conductors and said column conductors on each reading cycle and selectively varying the number of row conductors and number of column conductors energized on each cycle, an output connection, and selective connecting means for connecting each pixel to said output connection in a given reading cycle only if both the row conductor and the column conductor associated with that pixel are energized during such cycle, whereby said reading means will select one or more of said pixels on each cycle, said output connection including two output sense lines, said selective connecting means including means for selecting one of said two output sense lines on each cycle and connecting all of the pixels selected on that cycle to the one of said two output sense lines which has been selected on that cycle.

A photooptical sensor comprising:

• an array of pixels, each said pixel including means for providing a pixel signal related to the illumination incident on that pixel;
• and
• reading means coupled to the array for reading out said pixel signals cyclically so that each such reading cycle corresponds to the time interval in which one of said pixel signals is read out from one of said pixels, said reading means being operable to selectively vary the number of pixel signals read out on each such cycle so that on some of said reading cycles a plurality of said pixel signals are read out of said pixels simultaneously, whereas on others of said reading cycles only one of said pixel signals is read out of said pixels, said pixels being arranged in R rows and C columns, said columns extending generally transverse to said rows, where R and C are integers greater than one, said reading means including R row conductors, each said row conductor being associated with the pixels in one of said rows and C column conductors, each said column conductor being associated with the pixels in one of said columns, whereby each said pixel is associated with one said row conductor and one said column conductor, said reading means further including means for selectively energizing said row conductors and said column conductors on each reading cycle and selectively varying the number of row conductors and number of column conductors energized on each cycle, an output connection, and selective connecting means for connecting each pixel to said output connection in a given reading cycle only if both the row conductor and the column conductor associated with that pixel are energized during such cycle, whereby said reading means will select one or more of said pixels on each cycle, said output connection including two output sense lines, said selective connecting means including means for connecting different ones of said pixels selected on different cycles to different ones of said two output sense lines,
• the sensor further comprising means for deriving a Walsh-Hadamard transformation of the pixel signals of a portion of the array from the signals appearing on said output sense lines.