Compact visible laser sources based on frequency-doubled /spl alpha/-DFB laser diode

Summary form only given. We report the generation of blue and green laser light by single-pass frequency doubling of a novel high-power single-mode laser diode in a 1-cm-long quasi-phase-matched periodically poled LiNbO/sub 3/. The IR source is an angled-grating distributed-feedback (/spl alpha/-DFB) laser diode. Because of the high-power spatially coherent beam, efficient frequency doubling may be obtained without resonant cavity with stringent wavelength requirements or single-mode nonlinear waveguide with strict positional alignment tolerances. Furthermore, the /spl alpha/-DFB is relatively more tolerant to optical feedback, thus eliminating the need for costly and bulky optical isolators.