Accurate spectroscopic wavelength determination of pulsed lasers

We present a simple, easy, and straightforward spectroscopic approach for t he determination of the wavelength of pulsed laser systems with an accuracy of less than or equal to 0.006 cm(-1) (180 MHz). This is better than curre ntly realised by the best commercially available wavemeters for pulsed lase r systems. As an example, the temperature dependence of the emitted wavelen gth of a pulsed Nd:YAG laser has been studied in detail. Our measurements i ndicate that the passively Q-switched monolithic nonplanar ring-oscillator Nd:YAG laser with a free spectral range of the resonator of about 5.8 GHz c an be tuned without mode hops over a range of 3.8 GHz. The concept is gener ally applicable to any other wavelength regions of interest.