HIGH DYNAMIC RANGE SOLID STATE IMAGE SENSOR AND CAMERA SYSTEM

A high dynamic range solid state image sensor and camera system are disclosed. In one aspect, the solid state image sensor includes a first wafer including an array of pixels, each of the pixels comprising a photosensor, and a second wafer including an array of readout circuits. Each of the readout circuits is configured to output a readout signal indicative of an amount of light received by a corresponding one of the pixels and each of the readout circuits includes a counter. Each of the counters is configured to increment in response to the corresponding photosensor receiving an amount of light that is greater than a photosensor threshold. Each of the readout circuits is configured to generate the readout signal based on a value stored in the corresponding counter and a remainder stored in the corresponding pixel.