High efficiency second harmonic generation vertical external cavity surface emitting laser

摘要

A vertical external cavity surface emitting laser (VECSEL) in which the full-width at half maximum (FWHM) of laser light is reduced by two etalon filter layers to improve the efficiency of second harmonic (SHG) crystal is provided. The VECSEL includes: a laser chip for generating laser light; a first etalon filter layer formed on the laser chip; a second etalon filter layer that is formed on the first etalon filter layer and has a different refractive index than the first etalon filter layer; a first mirror separated from and disposed obliquely to the laser chip; a second mirror for reflecting the laser light reflected from the first mirror back to the first mirror to form a cavity with the laser chip; and an SHG crystal disposed along an optical path between the first and second mirrors and doubles the frequency of the laser light generated in the laser chip.