Abstract: This invention discloses an optical detector system, including a photo detector generating an electrical current according to light received thereby, voltage terminals at opposite sides of the photo detector for connection to a voltage source, a pair of resistors each connected between a voltage terminal and the respective side of the photo detector, a pair of matched amplifiers each having an input connected to the juncture between the respective resistor and the respective side of the photo detector, each of the matched amplifiers having an input resistance substantially less than that of the resistor to which it is connected, and an output circuit combining the outputs of the matched amplifiers.