Question

Fluoroptic temperature sensors work on the principle of _______

(a) thermistor

(b) thermocouple

(c) optical fiber

(d) rtd

I got this question in a national level competition.

I would like to ask this question from Biosensors in portion Physiological Transducers of Biomedical Instrumentation

Answer 1

Correct choice is (c) optical fiber

To explain: Fluoroptic temperature sensors work on the principle of optical fiber sensors. They contain a rare earth phosphor which is illuminated by a white light along a short length of large core optical fibre. The light excites the phosphor which emits a number of lines. By using filters, two of these lines at 540 and 630 nm are selected, and the ratio of their intensities is a single valued function of the temperature of the phosphor.