Apparatus for combining light from a plurality of coherent light sources

An apparatus for combining coherent light from a plurality of coherent light sources, the apparatus comprising:

• a plurality of light guides, each of said plurality of light guides comprising:
• an entrance face and an exit face;
• a first mirror at said entrance face, said first mirror comprising an aperture for admitting light therein from a respective one of said plurality of coherent light sources;
• and
• a second mirror at said exit face, said second mirror being partially-reflective and enabled to transmit a first portion of said light and reflect a second portion of said light back towards said first mirror;
• and
• a second stage light guide for combining emitted light exiting said plurality of light guides, said second stage light guide comprising:
• a second stage entrance face and a second stage exit face, said second stage entrance face for receiving said emitted light from each said exit face of said plurality of light guides;
• and
• a third mirror, at said second stage exit face, for reflecting said light back towards said second mirror, said third mirror comprising an exit aperture for said light to exit said second stage light guide.