Patent ID: 7376167
Filing Date: 2008-05-20
Classification: G02B,H01S

Abstract:
1. A tunable ring laser device comprising: a ring laser comprising a ring resonator element and an optical gain element that forms part or all of the ring resonator element, the ring resonator element and optical gain element being operable in combination to generate a laser emission at a range of frequencies decided by a resonant frequency of the ring resonator element; a coupling element for extracting laser emission from the ring laser; and a frequency selection element located outside the ring resonator element, and not forming part of the ring resonator element, the frequency selection element being connected to the ring resonator element by way of the said coupling element, and being operable to reflect a part of the extracted laser emission into the ring resonator element, and to select the frequency of said part of the extracted laser emission; said frequency selection element incorporating a mechanism for changing the frequency of the reflected light.