Patent ID: 7636376

Claim:
A laser source tunable in wavelength with a degenerate self-aligned external cavity comprising: an amplifier waveguided medium placed inside the external cavity, a lens assembly to collimate the light from said waveguide amplifier, a reflective volume holographic grating element as the output coupler and the wavelength selective component of the external cavity wherein, said volume holographic grating element has a grating vector substantially non-parallel with respect to the first collimated beam and receives a first and second collimated beam and generates a first and second filtered beam wherein, the first filtered beam is propagating in a direction opposite and substantially non-parallel with respect to the first collimated beam and the second filtered beam is propagating in a direction opposite and substantially parallel to said first collimated beam and providing optical feedback to said waveguide amplifier, a mirror positioned adjacent to said waveguide amplifier wherein, the reflective facet of the mirror is placed at the focal plane of said lens assembly and which receives and reflects said first filtered beam to produce said second collimated beam after collimation from said lens assembly wherein, said second collimated beam produces said second filtered beam upon diffraction from said volume holographic grating element.