Vertical external cavity surface emitting laser including second harmonic generation crystal having mirror surface

Abstract

Provided is a VECSEL having an SHG crystal with a mirror surface. The VECSEL includes a laser chip, a folding mirror, and the SHG crystal. The laser chip emits rays having a first wavelength, and the folding mirror is disposed a predetermined distance from the laser chip and obliquely disposed with respect to the laser chip to obliquely reflect rays having the first wavelength emitted from the laser chip. The SHG crystal doubles a frequency of rays having the first wavelength reflected by the folding mirror to form rays having a second wavelength. A coating layer is formed on an emitting surface of the SHG crystal to reflect rays having the first wavelength whose frequency has not been doubled and transmit rays having the second wavelength whose frequency has been doubled in one embodiment, whereas in another embodiment it reflects the second wavelength for emission from the back surface of the folding mirror with a different combination of coatings on incident and emitting surfaces.

Dependencies are inferred from the claim text.