Proceedings Article | 24 January 2008
Proc. SPIE. 6829, Advanced Materials and Devices for Sensing and Imaging III
KEYWORDS: Sensors, Glasses, Laser processing, Optical testing, Semiconductor lasers, Optoelectronics, Signal processing, Signal detection, Product engineering, Laser systems engineering
During the production of Low-E (Low-Emission) glass, the distance between Low-E membrane reactor and the float
glass impacts the thickness of Low-E membrane coated, and the quality of products. The system, designed to measure
the displacement of the reactor, which represents the distance between Low-E membrane reactor and the float glass, will
work in the industrial condition of high temperature and strong interference. On the consideration of non-contact,
noninvasive and high-speed, a measure system by PSD (Position Sensitive Detector) based on Laser-Triangulation
method is designed and a prototype made. In this system, a laser beam, generated by a semiconductor laser generator,
focuses on the underside surface of the Low-E membrane reactor made of graphite. And then, the laser spot on the
underside surface, through a small focus lens, is detected by a 1D-PSD (One-Dimension Detector). The electric signal,
reflecting the position of the small laser spot on the PSD, is amplified and processed by amplifier and signal processing
circuit, then is sampled by a A/D converter. Based on the Laser-Triangulation method, the displacement can be computed.
Trial shows, the system based on Laser-Triangulation method meets the requirements of high-speed, noninvasive,
non-contact, and to some extent diminishes the influence of nonlinearity and dark current of the PSD.
