This report describes work undertaken to design and build a pressure gauge utilizing a unique pick‐off which couples the phenomena of electroluminescence and photoconductivity to obtain a completely solid‐state device having a low impedance output capable of detecting very small mechanical displacements (microinches) of bellows and diaphragm pressure sensors. Advantages of this device as applied to pressure measurement are small size and weight, very high resistance to shock and vibration, and continuous resolution over a wide dynamic range. A prototype pressure gauge capable of measuring pressures from 0 to 800 mm Hg and having an electrical output of 1 to 5 V when operated from a 28‐V dc power source is described.