Sensitivity and Selectivity of an Ozone Sensor for the UV Spectrum

Abstract

The use of optical retro-reflectors in improving the sensitivity of an optical sensor base on optical absorption spectroscopy for the measurement of ozone gas to increase optical path length is presented in this article. Two optical retroreflectors were employed in the design of a 20cm absorption gas cell. Our analysis shows that, in the 20cm gas cell we can achieve a sensitivity value of 0.0681ppm. However these sensitivity values are dependent on the optical density of the sensor. In addition the 20 cm gas cell has a better potential for a faster sensor response time. Also, at 253.7nm, ozone can be detected with minimal interference in the presence of CO2 and SO2 .