Thermodynamics infrared imaging sensor

Abstract

An infrared imaging system is presented wherein a visual image of a scene being viewed is obtained from the thermal energy radiated from said scene. The thermal energy radiated is focused onto a plurality of means for absorbing energy from the infrared radiation, specifically a two-dimensional array of gas cells with the front end being a rigid infrared transparent window, the sides being rigid, and the rear ends being flexible membranes. Infrared radiation absorbed by the cells causes changes in the thermodynamic pressure within each cell and consequent expansion of the flexible membrane on the rear end of each cylindrical cell. The deflection of these flexible membranes is monitored and measured by either a laser interferometer system or a solid state pressure sensing system. Measurement of this deflection represents the amount of infrared radiation received at each of the plurality of gas cells. The resultant intensity of the laser interference beam is monitored with a laser interferometer and a TV vidicon camera. This resultant intensity reflects the magnitude of deflection from the cells. The TV vidicon signal which monitors the resultant intensity is processed and transmitted for two-dimensional video presentation of the viewed scene.