We propose and demonstrate a novel approach to achieving rapid and phase-coherent continuous broadband tuning of a single-mode external-cavity semiconductor laser. Two internal acousto-optic devices control the angle of incident light on a diffraction grating and the effective round-trip phase electronically. Although the present implementation derives the phase from a long delay line and is not yet mode-hop free, the new approach lends itself to fully electronic control.
© 2000 Optical Society of America
M. Kourogi, K. Imai, B. Widyatmoko, T. Shimizu, and M. Ohtsu, "Continuous tuning of an electrically tunable external-cavity semiconductor laser," Opt. Lett. 25, 1165-1167 (2000)