Optical scanning element

Patent metadata

Field	Value
Publication number	US-11385334-B2
Application number	US-201916237860-A
Country	US
Kind code	B2
Filing date	Jan 2, 2019
Priority date	Jul 7, 2016
Publication date	Jul 12, 2022
Grant date	Jul 12, 2022

Abstract

An optical scanning device includes a supporting body 2; an optical waveguide composed of a single crystal having electro-optic effect and integrated with the supporting body directly or through a clad layer; a plurality of periodic domain inversion parts formed in the optical waveguide, the periodic domain inversion parts having periods different from each other; and a plurality of electrodes capable of applying voltages on the periodic domain inversion parts, respectively, to generate diffraction gratings in the periodic domain inversion parts, respectively. The clad layer is composed of a material having a refractive index lower than a refractive index of the single crystal forming the optical waveguide. Each of the periodic domain inversion parts on which the voltage is applied is selected to generate the diffraction grating in the selected periodic domain inversion part so that a propagation light propagated in the optical waveguide is emitted to the outside of the optical scanning device as a diffracted light.

First claim

The invention claimed is:

1. An optical scanning device for selectively emitting a diffracted light in at least one of a plurality of directions that are different from each other, said device comprising:
a supporting body;
an optical waveguide comprising a single crystal having electro-optic effect and integrated with said supporting body directly or through a clad layer;
a plurality of periodic domain inversion parts formed in said optical waveguide, said periodic domain inversion parts having periods different from each other;
a plurality of electrodes, each being capable of applying a voltage on each of said periodic domain inversion parts to generate a diffraction grating in each of said periodic domain inversion parts; and
a side face clad provided between said optical waveguide and said electrodes,
wherein said clad layer and side face clad comprise materials having refractive indices lower than a refractive index of said single crystal forming said optical waveguide, respectively;
wherein each of said periodic domain inversion parts on which said voltage is applied is selected to generate said diffraction grating in said selected periodic domain inversion part, and said diffraction grating is not generated in each of the said periodic domain inversion parts which is not selected, wherein said diffraction grating is capable of emitting said diffracted light in said one of said plurality of directions; and
wherein a propagation light is propagated in said optical waveguide and said diffracted light is emitted from said diffraction grating generated in said selected periodic domain inversion part to the outside of said optical scanning device in said one of the said plurality of directions.

2. The device of claim 1 , wherein said optical waveguide is integrated with said supporting body through said clad layer.

3. The device of claim 1 , wherein Tsub/λ, is 0.6 or higher and 50 or lower, provided that Tsub is assigned to a thickness of said optical waveguide and λ, is assigned to a wavelength of said propagation light propagating in said optical waveguide.

4. The device of claim 1 , wherein said single crystal has a polarization direction perpendicular to a propagation direction of said optical waveguide,
wherein said polarization direction of said single crystal is inclined with respect to a normal direction of a surface of said optical waveguide by an angle of 80° or larger and 100° or smaller, and
wherein each of said electrodes is formed on the outside of said side face clad.

5. The device of claim 1 , wherein said diffracted light comprises a first-order diffracted light.

6. The device of claim 1 , wherein said diffracted light comprises a second-order or higher-order diffracted light.

7. The device of claim 1 , wherein said diffracted light comprises diffracted lights of a plurality of orders different from each other, said diffracted lights being emitted.

8. A method of scanning a surface to be measured using said optical scanning device of claim 1 , said method comprising:
irradiating said emitted light emitted from said optical scanning device onto said surface to be measured; and
obtaining data relating to said surface to be measured using a reflection light reflected by said surface to be measured.

9. The method of claim 8 , wherein said surface to be measured is scanned while said optical scanning device is moved in a lengthwise direction of said optical scanning device.

10. The device of claim 1 , wherein said diffracted light comprises a first-order diffracted light and a second-order or higher-order diffracted light.

11. The device of claim 1 , wherein the plurality of electrodes are provided on both ends of the respective periodic domain inversion parts on opposite side faces of said optical wave guide.

Assignees

• Ngk Insulators Ltd

Inventors

• Kondo Jungo
• Okada Naotake
• Ejiri Tetsuya
• Asai Keiichiro
• Yamaguchi Shoichiro

Classifications

• G02F1/2955 Primary

  by controlled diffraction or phased-array beam steering (controlled diffraction for optical waveguide switching G02F1/313) · CPC title

• G02F1/295

  {Analog deflection from or} in an optical waveguide structure] · CPC title

• G01S7/481

  Constructional features, e.g. arrangements of optical elements · CPC title

• G01S7/4818 Primary

  using optical fibres · CPC title

• G01S7/499

  using polarisation effects · CPC title