A NEW SOLID STATE RELATIVE HUMIDITY METER IS PROPOSED USING AN INTRINSICALLY STABLE PRIMARY SENSOR AND ACCURATE DIGITAL CIRCUITRY.

A NEW SOLID STATE RELATIVE HUMIDITY METER IS PROPOSED USING AN INTRINSICALLY STABLE PRIMARY SENSOR AND ACCURATE DIGITAL CIRCUITRY. THE INSTRUMENT IS BASED ON THE WELL PROVEN TECHNOLOGY OF THE RHICON SENSORS WHICH PROVIDE A WELL OPTICAL TRANSITION AT FIXED, PREDETERMINED VALUES OF WATER VAPOR PRESSURE. SINCE THESE TRANSITIONS ARE BASIC UNVARYING NATURAL PHENOMENA AT THE MOLECULAR LEVEL THEY INSURE THE LONG TERM, NON DRIFTING, ABSOLUTE PRECISION OF THIS TECHNOLOGY. THE HYGROMETER MAKES USE OF THIS OPTICAL TRANSITION TO OPERATE AS A WARM MIRROR DEW POINT INSTRUMENT, THUS BECOMING A SIMPLE, RUGGED, PRIMARY, ACCURATE DEVICE WITH LONG TERM STABILITY AND REALIZABLE AT A MODEST COST. THE APPROACH IS NEW YET THE TECHNOLOGY USED, BOTH CHEMISTRY AND ELECTRONICS, IS WELL ESTABLISHED AND WITH ABUNDANT EXPERIMENTAL DATA AVAILABLE. IT IS PROPOSED THAT A FULL SCALE HYGROMETER BE BUILT AND TESTED UTILIZING DISCRETE COMPONENTS. THE RESULTS OF THIS WORK WILL PROVIDE THE BASIS FOR THE DEVELOPMENT OF AN LSI CHIP, INTEGRATING BOTH SENSORS AND ELECTRONICS DURING PHASE II.