Precisely tunable, narrow-band pulsed dye laser

Anarrow-band, precisely tunable dye laser pumped by an injection-seeded YAG laser is described. The laser achieves an output of 100 mJ/pulse and 40% efficiency when one uses Rhodamine 6G dyes. The output pulse is Gaussian both in time and spatial profile. The laser oscillator employs an intracavity étalon that is repetitively pressure scanned over one free spectral range while the grating successively steps to consecutive étalon modes. We pressure scanned the étalon under computer control using a bellows. Methods are described for calibrating the tuning elements for absolute precision. We demonstrated that the laser has an absolute precision of ±0.4 pm over a 1.0-nm scan. This accuracy is achievable over the wavelength range of a dye.