Verfahren und Anordnung zur Stromversorgung eines Messlasers, insbesondere eines Diodenlasers zur absorptionsspektroskopischen Spurengasanalytik

The invention relates to a process and a setup for the power supply of a measurement laser, in particular a diode laser for absorption-spectroscopic trace gas analysis. According to the invention, a diode laser power supply output stage with an extremely low bandwidth is used, whereby there is full electrical isolation between the direct-current diode laser power supply and a tuning signal implemented in the diode laser using optical means. Faults, which otherwise access the diode laser via the power supply, are suppressed efficiently by means of the low bandwidth of the laser power supply, which no longer depends on the frequency of the signal required for tuning; this permits stable operation of the laser and this is the basis for high sensitivity in the measuring system equipped accordingly. To prevent a phase shift between the optical signal for tuning the diode laser and the resulting frequency change in this signal, a thermal-optical projection and the supply of a defined quantit y of heat emanating from the tuning laser take place directly in the region of the pn transition between the measurement and diode lasers.