High yield DFB laser with effective reject selection

摘要

The present invention relates to a high yield DFB laser with an effective reject selection using criteria on threshold current. The demand for high output power often will require use of lasers with asymmetric power distributions with most of the light power coming out from the front mirror. The laser according to the invention preferably has an as-cleaved back mirror, an AR-coated front mirror and a 90- degree phase shift (wavelength/4) positioned at 43% of the laser length counted from the rear mirror. This type of laser gives a good SM-yield, an advantageous power asymmetry and a possibility to select good lasers using the threshold current as selection parameter.