TIME-RESOLVED BREAST IMAGING DEVICE

A photodetection circuit for use in a laser imaging apparatus comprises a photodetector (30) adapted to respond to a laser pulse exiting from a breast being scanned; a multi-gain preamplifier circuit (40) connected to the output of the photodetector; a switch (140) connected to the output of the multi-gain preamplifier for sampling the output of the photodetector; an RC circuit (142) for spreading the sampled signal; an amplifier (142) connected to the output of the RC circuit; and an integrator (146) for integrating each sample of the output. A time-gating circuit (108) 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 (104) 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.