Novel geometry for single-mode scanning of tunable lasers

A geometry that allows for the single-mode scanning of lasers that use a diffraction grating as the dispersive element is described. It is observed that under the right conditions a rotation of the tuning element can provide changes simultaneously in cavity length and diffraction angle that exactly match the requirements needed for continuous single-mode scanning. As a case study, the method is applied to the grazing-incidence pulsed dye laser.