Measuring device for temperature

Abstract

Abstract PURPOSE:To measure temperature highly precisely with a simple constitution by performing the measurement of temperature by utilizing a fact that refractive index of a substance changes according to temperature. CONSTITUTION:A light projected by a projector 11 passes through an optical fiber 13 and is reflected by a rotating mirror 20 and scanned in the direction of an arrow A. And, when it is reflected by the 1st reflecting mirror 211, it passes through the same optical path and is reflected by a semitransmitting mirror 14, transduced into an electric signal by a photoreceptor 15 and turned to be a starting signal for a counter and the like as a reference signal. Meanwhile, the light scanned in the direction of an arrow A' enters a prism 23a, undergoes total internal reflection on the interface with the substance 23b while the incident angle alpha is of a prescribed size, is reflected by a reflector 24, and, passing through the same optical path, is received by the photoreceptor 15. When the incident angle alpha becomes smaller than a prescribed value, the light entering the prism 23a transmits through the substance 23b. Since the refractive index of the prism 23a changes when the temperature thereof changes, the temperature can be known from a time until a reflected light becomes absent at the photoreceptor 15.

Inventors

• 👤 Ichiro Wada

Bibliographic Details