IMAGING DEVICE WITH PRE-CHARGED SIGNAL LINE

The invention is directed to an imaging device and a method of operating the imaging device, which will reduce banding in the image caused by parasitic capacitance. The imaging device comprises an array of pixels arranged in rows and columns and column signal lines adapted to be selectively coupled to the rows of pixels at predetermined times. Each pixel element has a photodetector coupled to a reset switch for receiving a reset signal to reset the photodetector. The imaging device further includes a precharge circuit adapted to place a voltage on the column signal lines. The method of operating the imaging device includes the steps of applying a precharge voltage to the signal lines, resetting the photodetectors in a row, integrating the photodetector voltage as light impinges on the reset photodetectors, coupling the integrated photodetectors to the signal lines, and sampling the integrated voltage coupled to each of the signal lines. When the double sampling technique is used, the steps further include resetting the photodetectors and sampling the photodetector reset voltages on the signal lines. The precharge voltage is applied to signal lines during the integration period of the photodetectors and is disconnected from a signal line during sampling.