Optical Systems Program Light Modulation System

Vibration camcorder undergoing field testing

• AC-coupled 16x16 photodiode array
• 256 parallel channels of filtered, amplified and digitized output
• 1kHz frame rate
• 140dB (24-bit) effective dynamic range

This sensor achieves both high sampling rate and large effective dynamic range. It can resolve minute modulations riding on a large ambient light level. Fourier processing of all channels allows temporal-frequency imaging, producing images of light modulation at particular frequencies of interest. The sensor lends itself to applications where one is interested in stationary (fixed-frequency) light modulations, and allows high sensitivity because one can select a narrow bandwidth similar to a lock-in approach.