A NEW PORTABLE INFRA-RED AMBIENT AIR MONITOR

摘要

Infra-red analysis is widely used for detecting and quantifying toxic vapors in ambient air. This paper describes the design, calibration and operational features of a new, microprocessor-controlled smart portable IR analyzer, which is precalibrated at the factory for over a hundred OSHA-cited toxic gases. Automatic servo systems for selection of both analytical wavelength and gas cell pathlength are described. Production analyzers are optically "cloned" from factory reference analyzers using a computer-controlled optical bench. Memory space is available for users1 own calibrations as well as the factory data, and a unique curve-fitting algorithm provides correction for calibration curve non-linearities. The electro-optical and uP-controlled systems of the new analyzer are described in some detail.