TDLAS Method and Apparatus for Monitoring Port Blockage for TDLAS Measurements in Harsh Environments

摘要

A method for monitoring failure of a sight tube mounted on a wall of a process chamber, wherein the sight tube operates in conjunction with a TDLAS optical head with a window between the sight tube and the TDLAS optical head. The method includes providing an optical sensor in the TDLAS optical head, the optical sensor being arranged to receive light output by a light output process in the process chamber. An output signal generated from light output by a light output process in the process chamber and received by the photosensor is monitored. It is determined whether the output signal is decreased.