Abstract

The proposed cavity design uses gratings as highly dispersive elements to produce enough dispersion to make the ratio of the fractional pathlength change to the fractional wavelength change approach unity. Under this extreme adjustment all wavelengths would have the same round trip phase condition and correspond to the same mode. Figure 1 shows a laser cavity employing two equivalent gratings. The gratings are parallel to ensure that parallel rays of different wavelengths (marked red and blue) entering from the left arc parallel¹ when reaching the cavity end mirror. This version then does not use a grating to tune the lasing frequency by beam misalignment.

© 1992 Optical Society of America