| 摘要 |
A semiconductor image sensor comprises an array of charge collection elements buried within the semiconductor for collecting charge photogenerated in response to the image. This sensor is easily configured to discern changes in an image. One or more charge transfer devices (CTD's) of an array are associated with each column of charge collection elements. For readout, the charge collected by each charge collection element is transferred to an associated storage cell of an array CTD associated with the column in which that charge collection element is disposed. For discernment of moving targets or image changes, a difference between the charge collected by a given charge collection element during a first frame and a second frame is determined. To discern a moving target, each column of charge collection elements has a first and a second array CTD associated therewith and a first image frame of charge is collected, transferred to and stored in the channels of the first array CTD's, after which a second image frame of charge is collected, transferred to and stored in the channels of the second array CTD's. The charges in the first and second array CTD's are then read out in parallel, thereby transferring the image frames in parallel. Output CTD channels positioned to accept charge from the channels of the array CTD's have special charge transfer control structures for transferring the charge from the channels of the array's first CTD's to the channel of a first output CTD and from the channels of the array's second CTD's to the channel of a second output CTD to ensure that parallel transfer of the image frames continues in the output CTD's. This parallel in the array, parallel in the output (parallel-parallel) CTD transfer architecture minimizes interframe cross-talk and maximizes resolution. Interleaved first and second array CTD's to which charge may be selectively transferred are achieved by splitting the propagation electrodes for one phase into two electrodes each in order to control charge transfer from the charge collectors to the first and second associated CTD's independently. The CTD's (array and output together) may be combined with a prior art single-frame-at-a-time imager to form a system which appears (at the external system output) to be the same as the monolithic structure.
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