| 摘要 |
In a laser gas analyzer using a frequency modulation method, a light source portion 204 comprises a laser driving signal generation portion 204s which combines a wavelength scanning driving signal that varies the emission wavelength of a laser so as to scan the absorption wavelength of the gas for measurement and a high-frequency modulation signal to modulate the emission wavelength, and which outputs the result as a laser driving signal; a current control portion 204c; a laser element 204e; a thermistor 204f; a Peltier element 204g; and a temperature control portion 204d. A signal processing circuit 208 comprises a synchronous detection circuit 208b which detects the amplitude of the frequency-doubled component of the modulation signal from the output signal of a light-receiving portion 207, and a computation portion 208e. |
