Diode laser sensor for process control and environmental monitoring
نویسندگان
چکیده
Absorption spectroscopy with tunable diode lasers (TDLAS) in the infrared region is a well-known technique for the chemical analysis of gas mixtures. The laser provides a high selectivity, which is important in industrial environments such as in-line stack monitoring, where complex gas mixtures are present. A wavelength tunable diode laser in the near infrared region has been utilized as a light source in absorption measurements of air pollution resulting from energy usage for industry. The emission frequency can be varied over a relatively wide spectral range by changing the current and temperature of the diode. # 1999 Elsevier Science Ltd. All rights reserved.
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