摘要 |
<p>A non-linear optical crystal (189), onto which a light with a first wavelength and a light with a second wavelength are coaxially shone, efficiently produces from the first-wavelength light a third light being a second higher harmonic thereof by non-critical phase matching or pseudo phase matching and almost coaxially outputs the second-wavelength light and the third-wavelength light. Therefore, a non-linear optical crystal (191) in the latter stage can efficiently produce a sum frequency without using optical path adjusting components for phase matching required in producing a sum frequency of the second-wavelength light and the third-wavelength light, enabling an efficient production of wavelength-converted light with a simple configuration.</p> |