Photosensitive charge-accumulating device and a lidar incorporating such a device

Abstract

The photosensitive device implements charge coupling and accumulation for analyzing a light signal. A sensor has an image zone M rows and N columns of photosensitive sites for receiving a light signal during successive acquisition periods, a transfer zone of P rows and N columns of non-photosensitive sites for receiving, in each site of a first row, the sum of the charges in a respective column of the image zone at the end of each successive sampling period. It also has a storage zone of P rows an N columns in which each column is adjacent to a respective column of the transfer zone and each site is arranged to receive charges contained in an adjacent site of the transfer zone and to accumulate it. The sensor is clocked for a sequence. During each of R successive observation periods, there are P successive time samplings each of duration T, each by simultaneously transferring charges into the sites of the storage zone and subsequently transferring the charges from all sites into a single column into the first row of the transfer zone after moving charges of each row from the transfer zone to the following row. After P samples have been taken, the charges of each row of the transfer zone are transferred to the adjacent site of the storage zone. After R observation periods, the storage zone is read out row by row.