Coupling efficiency

Coupling efficiency for laser beam radiation of high quality

A coupling efficiency of > 80% is achieved when coupling laser sources with rotationally symmetric beams of high quality (M2 < 1.05) and no astigmatism.

Loss contributions are mainly through:

  • Transmission loss in the laser beam coupler ~  1%
  • Imaging aberration, stray loss and beam distortion (M2 > 1) ~ 8%
  • Fresnel reflection loss at fiber end faces ~ 8%