摘要 |
A wavelength conversion element is provided with a substrate including a nonlinear optical single crystal having a periodically poled structure, wherein a visible light transmittance of the substrate is 85% or higher when ultraviolet light is irradiated to the substrate. Further, a laser light having an average output of 1 W or more is outputted by shortening a wavelength of inputted laser light having a wavelength of 640 nm to 2000 nm. By improving visible light transmission characteristics when the ultraviolet light is irradiated in this way, a breakdown of crystal can be prevented and a stabilization of output characteristics at high output can be realized. As a result, an absorption of green light induced by ultraviolet light can also be suppressed and a saturation of output and the breakdown of crystal can be avoided.
|