Ultraviolet Oxygen Detector

摘要

An ultraviolet oxygen sensor has been investigated, designed, fabricated and tested which is to photoelectrically measure the partial pressure of oxygen in the pressure range from 100 to 500 torr. A krypton source was used to illuminate the Fery prism which is the dispersing element of a dual beam single monochromator set to pass energy in the Schumann-Runge absorption continuum band of oxygen in the wave-length region of 1450 to 1510 A. Since the absorption coefficient of oxygen has an average value of 350/cm in this band, absorption spectroscopy is employed in the measurement of oxygen concentration by passing the selected band of radiation from the monochromator through a .014 cm path length of oxygen gas. By monitoring the change in luminous energy falling on the photocathode of a photomultiplier tube, one can determine the partial pressure of the gas for a specified temperature. Lambert's Law demonstrates the change in intensity for a constant distance and due to the variation of k with a change in pressure. The partial pressure is read out directly on a 0-100 microamp meter which receives the signal from a ratioing, Darlington, current amplifier system. The amplifier obtains the primary signals from the current outputs of two RCA-type CF0129C phototubes positioned to detect light from an absorbing path and a reference path. (Author)