| 摘要 |
PURPOSE: To obtain an excellent homogeneous refractive index by carrying out a pulling up growth toward specific angled orientation to a phase matching angle corresponding to a used laser in the case of growing β-barium borate crystal. CONSTITUTION: The phase matching angle CO) of β-barium borate element by which a 2nd higher harmonic wave of 1.064μm oscillation light oscillated by Nd: YAG laser or the like is obtained, is orientation inclined by about 234 deg. from C-axis. Accordingly, a single crystal is grown up at pulling up orientation, θ=90-23=67 deg. from β-barium borate composition melt. Next, pulled up β-barium borate single crystal is cut down so as to become an element through which the laser beam passes in the vertical direction to the pulling up direction and is provided as a β-barium borate wavelength converting element that fluctuates refractive index (Δn) within ±10<-6> . |
