Optical readout system for membrane deformation measurements in a matrix optoacoustic infrared imager

An optical readout system for membrane deformation detection with spatial resolution is described in this work. The optical method is based on a visible light-emitting diode (LED), CMOS camera and Savart plate. The Savart plate splits a light beam from the LED into two coherent rays. The rays reflected from the membrane surface are focused on the camera and form the interference picture which varies with membrane deformation. The sensitivity of the given readout system to the membrane displacement is below 1 nm. The application of the proposed system to designing an uncooled matrix detector of infrared radiation is presented.