Time-resolved breast imaging device

The present invention relates generally to a diagnostic medical imaging apparatus and more particularly to a mammography machine that employs a near-infrared laser as a radiation source. A photodetection circuit for use in a laser imaging apparatus comprises a photodetector adapted to respond to a laser pulse exiting from a breast being scanned; a multi-gain preamplifier circuit connected to the output of the photodetector; a switch connected to the output of the multi-gain preamplifier for sampling the output of the photodetector; an RC circuit for spreading the sampled signal; an amplifier connected to the output of the RC circuit; and an integrator for integrating each sample of the output. A time-gating circuit is operably connected to the switch to open and close the switch at regular intervals of time during the occurrence of the output. A laser pulse synchronization circuit is operably connected to the time-gating circuit to provide a signal to the time-gating circuit as to when the laser pulse is expected to arrive at the photodetector.