Abstract: A high temperature optical probe for an optical gas temperature sensor includes a support, a generally conical hollow tip, and a joint physically interconnecting the support and the tip. The tip includes as an electromagnetic radiation emitter a sapphire-free ceramic selected from the group consisting of silicon carbide and silicon nitride. An optical lens supported in the tip is removable from the tip for repair and replacement. The joint is of a material and geometry to accommodate the thermal stresses caused by differences in thermal coefficients of expansion between the tip, joint and support, and the mechanical stresses caused by the interaction of the probe and the gas stream during high velocity movement of the gas stream past the tip. The joint sidewall is welded to the support and has a thickness of 0.008-0.012 inch where it overlaps the tip.

Abstract: A high temperature optical probe for an optical gas temperature sensor includes a support, a generally conical hollow tip, and a joint physically interconnecting the support and the tip. The tip includes as an electromagnetic radiation emitter a sapphire-free ceramic selected from the group consisting of silicon carbide and silicon nitride.