Improved Signal Output
Original Publication Date: 1980-Nov-01
Included in the Prior Art Database: 2005-Feb-14
Inficon's SENTINEL 200A has, as shown in Fig. 1, a sensor for monitoring evaporation rate which converts the vapor stream traveling through the sensor into photon energy. The frequency of the light is a function of the evaporant(s) and the amplitude at that frequency is a measure of deposition rate of that evaporant. The optical signal is conducted from the sensor via a 1/2-inch OD stainless steel (SST) tube. The surface (interior) of this tube is not reflective at the wavelengths being used, and thus a 1/R/2/ loss occurs as the signal (photon) travels to the quartz window isolating vacuum from the outside. If this 1/R/2/ loss could be eliminated, a significant signal improvement could be attained.