Reflex Level Gauge Principle

rent tube which is clamped to the gauge body. The sight glass has prismatic right angled grooves on the side facing the liquid and vapor space.”Based upon the presence of liquid or vapor area, external light waves incoming towards the reflex level gauge will undergo either absorption or reflection.

In case of vapors, the light radiations running into the groove surface are entirely reflected and returned back to the direction of observation. Thereby, the vapor area gives out silvery white appearance.

On the other hand, the light radiations which come across the surface of the grooves in the liquid region are fully absorbed owing to which the liquid at the back of the glass emerges black in color.