Wavelength conversion device and image display device

摘要

The present application discloses a wavelength conversion device. The wavelength conversion device includes a light source for generating excitation light, a laser medium for generating fundamental light from the excitation light, a resonator mirror for forming a resonator for the fundamental light in cooperation with the laser medium, and a wavelength convertor for converting wavelength from the fundamental light into harmonic light. The wavelength convertor includes a first end surface inclined by an angle θ from a surface orthogonal to an optical axis of the resonator and a second end surface parallel to the first end surface.

主权项

1. A wavelength conversion device comprising:
a light source configured to generate excitation light; a laser medium configured to generate fundamental light from the excitation light; a resonator mirror configured to form a resonator for the fundamental light in cooperation with the laser medium; and a wavelength convertor configured to convert wavelength from the fundamental light into harmonic light, wherein the wavelength convertor includes a first end surface inclined by an angle θ from a surface orthogonal to an optical axis of the resonator and a second end surface parallel to the first end surface, and the angle θ satisfies a relationship represented by Formulas 1 to 5 described below:Spreading⁢⁢Angle⁢⁢ofHarmonic⁢⁢Light<θ<θ⁢⁢1=12⁢tan-1(ϕ⁢⁢1+ϕ⁢⁢22L1)[Formula⁢⁢1] where, L1: length of the laser medium in an optical axis direction, and φ1 and φ2 are defined by Formula 2:ϕ⁢⁢1=2⁢(λ2⁢⁢π)⁢4⁢L⁡(R-L)⁢⁢ϕ⁢⁢2=ϕ⁢⁢1⁢1+2⁢(L1)2(π⁢⁢n0⁢ϕ124⁢⁢λ)2[Formula⁢⁢2] where, λ: wavelength of the fundamental light, L: resonator length, π: circular constant, R: curvature radius of the resonator mirror, and n0 is defined by Formula 3:n0=n′L′[Formula⁢⁢3]where n′ is defined by Formula 4 and L′ is defined by Formula 5:n′=n1⁢L1+n2⁡(L2-L1)+L2-L1cos⁢⁢2⁢⁢θ+L1cos⁢{sin-1⁡(n1n2⁢sin⁢⁢2⁢⁢θ)}[Formula⁢⁢4] where, n1: refractive index of the laser medium, n2: refractive index between the laser medium and the wavelength convertor, L2: distance from the laser medium to the wavelength convertor,L′⁢=L2+L2-L1cos⁢⁢2⁢⁢θ+L1cos⁢{sin-1⁡(n1n2⁢sin⁢⁢2⁢⁢θ)}.[Formula⁢⁢5]