Abstract

Active-passive mode-locking is an established technique for generation of reproducible ultrashort laser pulses. It combines the deterministic features of the active mode-locking with the short pulse generation, which is provided by the saturable-absorber passive mode-locker.¹ Recently, it was shown that a reflection device formed by a second harmonic generation crystal and a dichroic mirror with high reflectivity at the second harmonic can be used as a passive mode-locker.^2,3 Since it is a solid-state technique with a number of advantages, a combination with active mode-locking seems to be promising for the generation of stable and short laser pulses.

© 1991 Optical Society of America