Share Email Print

Proceedings Paper

Heat monitoring by fiber-optic microswitches
Author(s): Andrea A. Mencaglia; Massimo Brenci; Riccardo Falciai; Donatella Guzzi; Tania Pascucci
Format Member Price Non-Member Price
PDF $14.40 $18.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

In several industrial environments it can be necessary to utilize control devices connected to alarm systems for the monitoring of temperature variations, for example, those related to the occurrence of fires. In particular situations, such as in the presence of either electromagnetic interference or explosive substances, the use of a fiber optic device to control the increase of heat can be extremely convenient. This work is concerned with two micro-optic temperature switches based on bimetallic strip temperature behavior. The first type is constituted by two faced fibers: one fiber is connected with a LED source and is placed on a bimetallic strip; the other receives the light coming from the first one. The second device consists of only one fiber terminated with a GRIN microlens: light coming from the lens is reflected by a mirrored GRIN lens placed on a bimetallic strip and is then collected by the same fiber. A temperature variation causes a strip bending and, consequently, an intensity modulation of the transmitted radiation. Such devices are an improvement over traditional thermal microswitches; in fact, in the proposed configurations, the off condition is characterized by a reduction in, instead of an interruption of, the signal. It is thus possible to check for possible failures in operation (i.e., breaks in the fiber), as well as monitor the temperature. The second device is particularly suitable to be miniaturized and so it appropriate for realizing multiple-microswitch systems.

Paper Details

Date Published: 1 August 1991
PDF: 5 pages
Proc. SPIE 1506, Micro-Optics II, (1 August 1991); doi: 10.1117/12.45968
Show Author Affiliations
Andrea A. Mencaglia, IROE/CNR (Italy)
Massimo Brenci, IROE/CNR (Italy)
Riccardo Falciai, IROE/CNR (Italy)
Donatella Guzzi, IROE/CNR (Italy)
Tania Pascucci, IROE/CNR (Italy)

Published in SPIE Proceedings Vol. 1506:
Micro-Optics II
Anna Maria Verga Scheggi, Editor(s)

© SPIE. Terms of Use
Back to Top