High dynamic range, low-noise floating-gate photosensor

The floating-gate photosensor is a new method for detecting wideband photosignals that has high dynamic range and low noise. Low noise is achieved because the transduction from a photocurrent to a voltage uses capacitive coupling rather than the use of a load resistor. The floating-gate photosensor has demonstrated a noise equivalent power of 10 nW, a rise time of 50 nS, and a dynamic range of 10/sup 5/:1. The detector is AC coupled and has a square-root compressing transfer function for large photosignals.