Circuit with an exposure measuring unit for sensor controlled range measurement

Claim 1

A circuit having an exposure measuring portion and designed for sensor-controlled range measurement, comprising: two linear semiconductor image sensors having sensor elements; means for projecting line segments corresponding to two images separately obtained from an object onto the corresponding image sensors; an evaluator means connected to each of the sensor elements for switching between two different states depending upon whether a reference charge in the sensor elements is exceeded so as to digitalize sensor signals; an evaluating circuit means for evaluating the digitalized sensor signals in dependence upon varying relative position shifts with respect to a maximum correlation; device means connected to the evaluating circuit means for evaluating a range of said object; means for determining integration time of the sensor elements including strip-shaped comparing sensor elements positioned for exposure to an optically generated charge quantity which corresponds to a plurality of sensor elements in at least one of the image sensors; said comparing sensor elements being arranged along a longitudinal axis parallel to said at least one image sensor; dimensions of the individual comparing sensor elements along the longitudinal axis being substantially smaller than a corresponding dimension of the at least one image sensor; and each of the individual comparing sensor elements being connected via an evaluator means to associated inputs of a gate circuit means, an output of which represents an output of an exposure measuring portion which is formed of said comparing sensor elements, associated evaluator means, and gate circuit means, said evaluator means switching between two different states depending on whether a reference charge in the comparing sensor element is exceeded.