ARRANGEMENT COMPRISING A SEMICONDUCTOR LASER DIODE

摘要

PHN 9819 -6- An optical fibre is coupled to an end face of a semiconductor laser diode and the other end face is coupled to one end of a monomode optical waveguide. The other end of waveguide is terminated in a reflecting manner, e.g. by mirror, to reduce the coherence length of the laser. Thus so-called "speckle patterns" are only produced in the transmission fibre over a short distance from the laser and modal noise further on in the transmission fibre can be prevented by avoiding the use of non-ideal fibre couplings or other connections having a spatial filter effect within this short distance from the laser.