Tunable laser device and a method for producing light of respective selectable wavelengths

摘要

A tunable laser device (1) comprises integrally formed first and second ridge waveguides (5, 6). A longitudinally extending ridge (12) defines first and second light guiding regions (19, 20) of the first and second waveguides (5, 6) A plurality of first and second slots (27, 28) extending laterally in the ridge (12) adjacent the first and second waveguides (5, 6), produce first and second mirror loss spectra of the respective first and second waveguides (5, 6) with minimum peak values at respective first and second wavelength values. The spacing between the second slots (28) is different to that between the first slots (27) so that with one exception the minimum peak values of the first and second mirror loss spectrum occur at different wavelength values. The first and second waveguides (5, 6) are independently pumped with variable currents to selectively vary the common wavelength at which the minimum peak values of the first and second mirror loss spectra occur to produce Vernier tuning of the device.