A hybrid image sensor includes an infrared detector array and a CMOS
readout integrated circuit (ROIC). The CMOS ROIC is coupled to at least
one detector of the IR detector array, e.g., via indium bump bonding.
Each pixel of the CMOS ROIC includes a first, relatively lower gain, wide
dynamic range amplifier circuit which is optimized for a linear response
to high light level input signals from the IR detector. Each pixel also
includes a second, relatively higher gain, lower dynamic range amplifier
circuit which is optimized to provide a high signal to noise ratio for
low light level input signals from the IR detector (or from a second IR
detector). A first output select circuit is provided for directing the
output of the first circuit to a first output multiplexer. A second
output select circuit is provided for directing the output of the second
circuit to a second output multiplexer. Thus, separate outputs of the
first and second circuits are provided for each of the individual pixel
sensors of the CMOS imaging array.