Theoretical and Experimental Investigations of an Opto-Pneumatic Detector

Abstract

The following is a theoretical and experimental study of an opto-pneumatic detector (OPD) used in an opto-pneumatic interface. This interface is capable of changing an optical signal into a pneumatic one, that can be amplified and then applied to pneumatic power stages. The opto-pneumatic interface offers the greatest promise in the automation of installations located under fire and explosive-hazardous conditions and under conditions where there are electromagnetic or radiation field actions, whereby electrical communication channel application is undesirable or impossible, and where pneumatic channels do not provide the required speed of response. The OPD is made up of a cell where an infrared light signal cuts into a black-body, increases its temperature, and generates a pressure signal in the chamber. The work has been carried out using different absorption body thickness, gas chamber volumes, different optical signal frequencies, and different fluid loads of the OPD. Following this, a mathematical model for numerical computation has been elaborated. The theoretical results were compared with the experimental results. [S0022-0434(00)00101-5]