Abstract: A method for operating an optical measuring system including a wavelength-tunable temperature-stabilized laser light source for measuring the concentration of a target gas in a measured gas, wherein an instantaneous base current IDC_ZG,act corresponding to a wavelength ?ZG of a target gas absorption line is set so that a wavelength distance ??DC defined during calibration between a target gas absorption line for a target gas and a reference gas absorption line for a reference gas is maintained. During operation, a temperature difference in the laser light source, defined in advance during calibration, between the operating points selected at the time of calibration of the reference gas, with a base current IDC_RG,cal, and the target gas, with a base current IDC_ZG,cal, is maintained by determining the required instantaneous base current IDC_ZG,act for the target gas, as a function of an instantaneous base current IDC_RG,act for the reference gas.

Abstract: A method for operating an optical measuring system including a wavelength-tunable temperature-stabilized laser light source for measuring the concentration of a target gas component in a measured gas, wherein an instantaneous base current IDC_ZG,act corresponding to a wavelength ?ZG of a target gas absorption line is set so that a wavelength distance ??DC defined during calibration between a target gas absorption line for a target gas component and a reference gas absorption line for a reference gas component is maintained. During operation, a relative temperature difference in the laser light source, defined in advance during calibration, between the operating points selected at the time of calibration of the reference gas, with a base current IDC_RG,cal, and the target gas component, with a base current IDC_ZG,cal, is maintained by determining the required instantaneous base current IDC_ZG,act for the target gas component, as a function of an instantaneous base current IDC_RG,act for the reference gas.

Abstract: A method for operating an optical measuring system for measuring the concentration of a gas component in a measured gas, based on wavelength modulation spectroscopy, wherein a laser light source is operated in a current-modulated manner with a base current IDC and a modulation current IAC and a laser beam of the wavelength ?0 having a wavelength modulation amplitude ??AC is emitted, and the wavelength modulation amplitude ??AC of the laser light is kept constant by way of variable setting of the current modulation amplitude ?IAC. The method provides for keeping a modulated power ?PAC at an internal resistor RI of the laser light source constant at the operating point so as to stabilize the wavelength modulation amplitude ??AC.