Patent ID: 8422120
Filing Date: 2013-04-16
Classification: G02F

Abstract:
1. A wavelength conversion element comprising a monocrystalline nonlinear optical crystal having an optical rotatory power, wherein the nonlinear optical crystal has: a plurality of first regions having a polarity direction along a predetermined direction; a plurality of second regions having a polarity direction opposite to the predetermined direction; an entrance face into which a fundamental incident wave having a wavelength λ and a frequency ω is incident in a direction substantially perpendicular to the predetermined direction; and an exit face from which a second harmonic with a frequency 2ω generated in the crystal emerges, and wherein the plurality of first and second regions are formed as alternately arranged in a period substantially equal to d expressed by Formula (3), Formula (4), Formula (5), or Formula (6) below, between the entrance face and the exit face, where n