TEMPORAL AND SPECTRAL CHARACTERISTICS OF THE OUTPUT OF AN EXCIMER LASER

The output of a Questek Model 2210 excimer laser, operated with XeCl fill, is characterized in both the time and frequency domains. Power spectra are obtained through use of the fast Fourier transform which show that the output is essentially white in character. Furthermore, noise power diminishes with repetition rate, reaching a broad minimum around 40 Hz. Analysis in the time domain shows a 'roughly Gaussian' distribution. Movement of optically opaque ('thick') particles in the path of the laser beam is shown to increase the variance of the noise, but not its low-frequency content.