Share Email Print

Proceedings Paper

Microprocessor Based Light Bridge Sensors
Author(s): Hal Philipp; Robert J. Marks II
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

Modern photoelectric proximity sensors typically employ the use of a pulse modulated IR beam, a photodetector, amplifier, synchronous demodulator, and comparator to generate an output signal that indicates the presence of an object in the sense field (Figure 1). While these types of photoelectric controls generally work to acceptable performance levels at reasonable cost, they generally require a manual adjustment and high gain optics to achieve reasonable sensitivity and dynamic range. Adjustment is usually performed by setting amplifier gain; sometimes this is performed with an AGC circuit. The use of an amplifier gain adjustment has the drawback of limiting sensitivity and dynamic range under many normal operating conditions.

Paper Details

Date Published: 29 November 1988
PDF: 7 pages
Proc. SPIE 0961, Industrial Optical Sensing, (29 November 1988); doi: 10.1117/12.947856
Show Author Affiliations
Hal Philipp, Philipp Technologies Corporation (United States)
Robert J. Marks II, University of Washington (United States)

Published in SPIE Proceedings Vol. 0961:
Industrial Optical Sensing
James Carney; Ernie Stelzer, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?