Multi wavelength laser device

Patent metadata

Field	Value
Publication number	US-9762022-B2
Application number	US-201315036193-A
Country	US
Kind code	B2
Filing date	Dec 5, 2013
Priority date	Dec 5, 2013
Publication date	Sep 12, 2017
Grant date	Sep 12, 2017

Abstract

The multi wavelength laser device includes a laser light source 10 that emits a plurality of laser lights 20 whose fundamental wavelengths differ from one another, a dispersing element 30 that changes the traveling direction of each of the plurality of laser lights according to the wavelength and the incidence direction, and that emits the laser lights in a state in which the laser lights are superposed on the same axis, and a wavelength conversion element 40 that has a plurality of polarization layers disposed therein and having different periods, and that performs wavelength conversion on the fundamental wave laser lights emitted from the dispersing element 30 and placed in the state in which the laser lights are superposed on the same axis, and emits a plurality of laser lights 50 acquired through the wavelength conversion in a state in which the laser lights are superposed on the same axis.

First claim

The invention claimed is:

1. A multi wavelength laser device comprising:
a laser light source to emit a plurality of laser lights whose fundamental wavelengths differ from one another;
a dispersing element to change a traveling direction of each of said plurality of laser lights emitted from said laser light source according to a wavelength and an incidence direction, and to emit said plurality of laser lights in a state in which said plurality of laser lights are superposed on same axis; and
a wavelength conversion element including a plurality of polarization layers disposed therein, said plurality of polarization layers including polarization inverted regions and polarization non-inverted regions having different periods, and performing wavelength conversion, in said polarization layers having different periods, on said plurality of laser lights emitted from said dispersing element and placed in the state in which said plurality of laser lights are superposed on said same axis, and emits a plurality of laser lights which are acquired through said wavelength conversion and whose wavelengths differ from one another in the state in which said plurality of laser lights are superposed on same axis, the wavelength conversion element including a structure in which periods of polarization inversion of said plurality of polarization non-inverted regions and said plurality of polarization inverted regions in said plurality of polarization layers increase or decrease gradually and continuously along a direction from an end portion thereof upon which said laser lights having the fundamental wavelengths are incident to an end portion thereof from which said wavelength conversion element emits the laser lights acquired through said wavelength conversion.

2. The multi wavelength laser device according to claim 1 , wherein said wavelength conversion element performs said wavelength conversion on the plurality of laser lights emitted from said dispersing element and placed in the state in which the plurality of laser lights are superposed on said same axis by performing wavelength conversion using at least one of second harmonic generation and sum frequency generation in said polarization layers, and emits the plurality of laser lights which are acquired through said wavelength conversion and whose wavelengths differ from one another in the state in which the plurality of laser lights are superposed on the same axis.

3. The multi wavelength laser device according to claim 1 , wherein said multi wavelength laser device further comprises an optical lens that is placed between said laser light source and said dispersing element, and that emits said plurality of laser lights which are emitted from said laser light source and whose fundamental wavelengths differ from one another toward same region on said dispersing element.

4. The multi wavelength laser device according to claim 1 , wherein said dispersing element has an angle adjustment mechanism that can adjust incidence directions of said plurality of laser lights whose fundamental wavelengths differ from one another.

5. A multi wavelength laser device comprising:
a pumping light source to emit a plurality of pumping lights for providing gains for laser media;
the laser media including respective end portions on a side of said pumping light source, said end portions allowing said pumping lights to pass therethrough and reflecting a laser light having a fundamental wavelength, and to perform optical amplification by using said plurality of pumping lights emitted from said pumping light source and emit a plurality of laser lights whose fundamental wavelengths differ from one another;
a dispersing element to change a traveling direction of each of said plurality of laser lights emitted from said laser media according to a wavelength and an incidence direction, and to emit said plurality of laser lights in a state in which said plurality of laser lights are superposed on same axis;
a wavelength conversion element including a polarization inverted region and a polarization non-inverted region which are formed periodically, and performing wavelength conversion, in said polarization inverted region and said polarization non-inverted region, on said plurality of laser lights emitted from said dispersing element and placed in the state in which said plurality of laser lights are superposed on said same axis, and emits a plurality of laser lights acquired through said wavelength conversion in the state in which said plurality of laser lights are superposed on same axis; and
a mirror to construct resonators for said plurality of laser lights whose fundamental wavelengths differ from one another, together with said end portions of said laser media on the side of said pumping light source, and to allow the plurality of laser lights emitted from said wavelength conversion element and acquired through said wavelength conversion to pass therethrough, and reflects said plurality of laser lights whose fundamental wavelengths differ from one another.

6. The multi wavelength laser device according to claim 5 , wherein said wavelength conversion element performs said wavelength conversion on the plurality of laser lights emitted from said dispersing element and placed in the state in which the plurality of laser lights are superposed on said same axis by performing wavelength conversion using at least one of second harmonic generation and sum frequency generation in said polarization layers, and emits the plurality of laser lights which are acquired through said wavelength conversion and whose wavelengths differ from one another in the state in which the plurality of laser lights are superposed on the same axis.

7. The multi wavelength laser device according to claim 5 , wherein said multi wavelength laser device further comprises an optical lens that is placed between said laser light source and said dispersing element, and that emits said plurality of laser lights which are emitted from said laser light source and whose fundamental wavelengths differ from one another toward same region of said dispersing element.

8. The multi wavelength laser device according to claim 6 , wherein said wavelength conversion element has a structure in which periods of polarization inversion of said plurality of polarization non-inverted regions and said plurality of polarization inverted regions in said plurality of polarization layers increase or decrease gradually and continuously along a direction from an end portion thereof upon which said laser lights having the fundamental wavelengths are incident to an end portion thereof from which said wavelength conversion element emits the laser lights acquired through said wavelength conversion.

9. The multi wavelength laser device according to claim 7 , wherein said wavelength conversion element has a structure in which periods of polarization inversion of said plurality of polarization non-inverted regions and said plurality of polarization inverted regions in said plurality of polarization layers increase or decrease gradually and continuously along a direction from an end portion thereof upon which said laser lights having the fundamental wavelengths are incident to an end portion thereof from which said wavelength conversion element emits the laser lights acquired through said wavelength conversion.

10. The multi wavelength laser device according to claim 5 , wherein said dispersing element has an angle adjustment mechanism that can adjust incidence directions of said plurality of laser lights whose fundamental wavelengths differ from one another.

Assignees

• Mitsubishi Electric Corp

Inventors

• Shoda Fumio
• Yanagisawa Takayuki
• Akino Yosuke

Classifications

• G02F2001/3503

  Physics · mapped topic

• H01S3/109 Primary

  Frequency multiplication, e.g. harmonic generation · CPC title

• H01S3/08054

  Passive cavity elements acting on the polarization, e.g. a polarizer for branching or walk-off compensation (quarter-wave plates in a Q-switch laser H01S3/1124, H01S3/115) · CPC title

• H01S3/08086

  Multiple-wavelength emission · CPC title

• G02F2201/305

  diffraction grating · CPC title