Accumulating optical detector with shutter emulation

A system for testing samples, comprising:

• an excitation source applying a series of excitations pulses to the sample;
• an optical sensor situated to image a desired area of the sample;
• a controller providing clock signal to the excitation source and a sync signal to the optical sensor;
• wherein the optical sensor comprises:
• an array of light sensors, an array of charge accumulators, and a switching circuit interposed between the array of light sensors and the array of charge accumulators;
• wherein the array of light sensors produces electrical current when illuminated by electromagnetic radiation, the array of charge accumulators accumulates electric charge when receiving the electrical current generated by the array of light sensors, and the switching circuit electrically isolates or connects the array of charge accumulators to the array of light sensors according to the sync signal.

A method for examining a sample, comprising:

• applying a series of excitations pulses to the sample;
• operating a light sensor array to image a selected area of the sample;
• energizing a switching array so as to connect the light sensor array to a capacitor array during selected time windows at time periods between the series of excitation pulses;
• and,
• using charge from the capacitor array to generate images of the sample.