Higher harmonics generator

Abstract

Abstract PURPOSE:To provide a higher harmonics generator through which phase matching is easily performed without carrying out complicated adjustment or control by preparing at a waveguide a means of dispersing the refractive index which offsets a refractive index difference between a basic wave laser beam obtained by dispersing wavelengths of nonlinear mediums and a high frequency wave laser beam. CONSTITUTION:At the upper surface of a nonlinear medium 1, a waveguide 2 is prepared in extension in the same direction as a crystal orientation of the nonlinear medium 1. At the upper surface of the waveguide 2, convex parts 3 are arranged at a prescribed pitch and a diffraction grating 4 is also prepared as a means of dispersing the refractive index which provides a refractive index distribution. The convex parts 3 are in succession arranged in the crystal orientation of the nonlinear medium 1 to shape a wave form. A basic wave laser beam is greatly different in the refractive index from that of the second higher harmonics and, what is more, the basic wave laser beam is so different in a beam intensity distribution from that of the second higher harmonics that the effective refraction index distribution receiving from the diffraction grating 4 makes a difference between two laser beams. As a result, differences of refractive indexes occurring because of a dispersion of wave lengths can be easily offset and phase matching conditions recognized between the basic wave laser beam and the second higher harmonics laser beam can be met satisfactorily and then a highly efficient transformation is carried out.

Inventors

• 👤 Morichika Yano
• 👤 矢野　盛規
• 👤 Toshiki Hijikata
• 👤 土方　俊樹

Bibliographic Details