Sensor apparatus

摘要

The invention provides a sensor apparatus (200) with compensated signal processing for generating a sensor signal corresponding to a filtered image of a scene. The apparatus (200) incorporates a multielement array (52) for providing at each element (58) first and second signals in response to first and second scene images projected onto it and a lens assembly (204) for projecting the images onto the array (52). Each element (58) is connected to an associated circuit (300). Each circuit (300) performs a subtraction of the first and second signals of its associated element from one another to provide a difference signal and supply this signal for use in generating the sensor signal. Each circuit (300) incorporates a transistor (T17) for injecting charge to compensate at least partially for subtraction accuracy degrading parasitic charge injection occurring within the circuit (300) when the apparatus (200) switches between projecting the first image and the second image onto the array (52).