Optical fibre receiving and laser beam combining unit

Claim 1

A laser system having a beam combining unit for combining the output beams of a plurality of high power lasers after the beams have been transmitted along optical fibres by focusing the beams to a common point, said laser system comprising: a plurality of high power lasers; an individual optical fibre, having a first end and a second end, associated with each laser, each laser being arranged to focus its output beam onto said first end of its associated optical fibre; and a beam combining unit for combining the output beams of the lasers, said beam combining unit including: holder means for receiving and holding the second ends of the optical fibres, an individual and discrete collimating lens associated with each optical fibre, each collimating lens being spaced from said second end of its associated optical fibre by a distance substantially equal to its focal length, each collimating lens being arranged to collimate the output beam from its associated optical fibre produce a collimated beam, and the optical axes of said collimating lenses being substantially parallel to each other, and a single focusing lens located on the opposite side of each of the collimating lenses from the holder means and having its optical axis parallel to the optical axes of the collimating lenses, the focusing lens being arranged to combine the collimated beams from the collimating lenses by focusing the collimated beams to a common point which is located on the opposite side of the focusing lens from the collimating lenses.