US 8,264,766 B2Granted

Wavelength conversion element, wavelength conversion method, phase matching method, and light source device

AssigneesNikon Corporation, National Institute for Materials Science

InventorsKenichi Muramatsu, Sunao Kurimura

Life of this patent

Estimating the term…

Loading patent…

Abstract

A wavelength conversion element is provided as one including a monocrystalline nonlinear optical crystal. 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. The plurality of first and second regions are formed as alternately arranged in a period substantially equal to d expressed by a predetermined expression, between the entrance face and the exit face.

Claims8

Dependent claims

A wavelength conversion element comprising a monocrystalline nonlinear optical crystal belonging to point group 32 or point group 3,

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 (1) or Formula (2) below, along a Z-axis direction of the crystal between the entrance face and the exit face,
[
Math
⁢
⁢
79
]
d
=
m
⁢
⁢
λ
2
⁢
(
n
+
⁡
(
2
⁢
ω
)
-
n
-
⁡
(
ω
)
)
(
1
)
d
=
m
⁢
⁢
λ
2
⁢
(
n
-
⁡
(
2
⁢
ω
)
-
n
+
⁡
(
ω
)
)
(
2
)
where n+(2ω) is a refractive index of right-handed circularly polarized light in the Z-axis direction of the nonlinear optical crystal for the second harmonic, n+(ω) a refractive index of right-handed circularly polarized light in the Z-axis direction of the nonlinear optical crystal for the fundamental incident wave, n−(2ω) a refractive index of left-handed circularly polarized light in the Z-axis direction of the nonlinear optical crystal for the second harmonic, n−(ω) a refractive index of left-handed circularly polarized light in the Z-axis direction of the nonlinear optical crystal for the fundamental incident wave, and m an order of QPM (quasi phase matching) and natural number.

66 more elements

Dependencies are inferred from the claim text.

Facts

Application: 12/588,501Filed 16 Oct 2009 · continuation in part
Priority: JP P2007-10912718 Apr 2007
Published: US 2010/0110534 A16 May 2010
Granted: 11 Sep 2012
Term ends: Not estimatedThe source records don’t support an estimate.

Classification3 codes

G02F 1/3775
In an optical waveguide structure: with a periodic structure, e.g. domain inversion, for quasi-phase-matching [QPM]
G02F 1/3558
Characterised by the materials used: poled materials, e.g. with periodic poling; Fabrication of domain inverted structures, e.g. for…
G02F
Optical devices or arrangements for the control of light by modification of