Linear motor or voice coil for fast tuning of a laser cavity

Patent metadata

Field	Value
Publication number	US-9871340-B2
Application number	US-201615294101-A
Country	US
Kind code	B2
Filing date	Oct 14, 2016
Priority date	Oct 16, 2015
Publication date	Jan 16, 2018
Grant date	Jan 16, 2018

Abstract

A tunable laser including: a reflecting mirror; a partially transmitting mirror; a gain medium energized by a pump source; a pair of mirrors surrounding the gain medium, a first prism and a second prism located between the gain medium and the reflecting mirror; the first prism receives radiation from the gain medium and disperses the radiation to the second prism; the second prism receives and directs the radiation towards an optical element which filters the spatially dispersed radiation based on the position to the second prism, the radiation resonates between the reflecting mirror and the partially transmitting mirror; the second prism is placed on a stage moved by a linear motor such that a desired center wavelength is obtained by moving the second prism to a position so as to allow radiation having the desired center wavelength to resonate between the reflecting mirror and the partially transmitting mirror.

First claim

What is claimed is:

1. A tunable laser comprising:
a reflecting mirror;
a partially transmitting mirror;
a gain medium;
a pair of mirrors surrounding the gain medium, one or two of the pair of mirrors being curved;
a pump source configured to energize the gain medium;
a first prism and a second prism located between the gain medium and the reflecting mirror;
wherein the first prism is configured to receive radiation from the gain medium and disperse the radiation to the second prism;
wherein the second prism is configured to receive the radiation from the first prism, and direct the radiation towards an optical element or an assembly of optical elements which filters the spatially dispersed radiation based on its position relative to the second prism, such that the radiation resonates between the reflecting mirror and the partially transmitting mirror;
wherein the second prism is placed on a movable stage such that a desired center wavelength of the laser output from the partially transmitting mirror is obtained by moving the stage carrying the second prism to a position so as to allow a portion of the dispersed radiation having the desired center wavelength to resonate between the reflecting mirror and the partially transmitting mirror; and
wherein the stage is moved by a linear motor configured to change the wavelength the laser output by at least 100 nm within 1 second.

2. The tunable laser of claim 1 , further comprising an aperture in front of the reflecting mirror.

3. The tunable laser of claim 1 , wherein the reflecting mirror is a curved mirror.

4. The tunable laser of claim 1 , further comprising a detector configured to detect the laser radiation output from the partially transmitting mirror.

5. The tunable laser of claim 4 , further comprising a controller configured to control the linear motor based on a result from the detector.

6. The tunable laser of claim 4 , wherein the controller is further configured to control the pump source based on a result from the detector.

7. The tunable laser of claim 6 , wherein the detector configured to detect a spectrum of the laser radiation output from the partially transmitting mirror.

8. The tunable laser of claim 1 , wherein the stage or an assembly of stages is movable in a two-dimensional plane, and is moved by a linear motor along one direction and by another linear motor along another direction.

9. The tunable laser of claim 1 , wherein the first prism is placed on another movable stage.

10. The tunable laser of claim 1 , wherein the reflecting mirror is placed on another movable stage.

11. The tunable laser of claim 2 , wherein the aperture is place on another movable stage.

12. The tunable laser of claim 1 , wherein the linear motor comprises an internal encoder to determine its position and the wavelength can be set through a lookup table.

Assignees

• Thorlabs Inc

Inventors

• Fendel Peter
• Sproles David
• Easter James
• Luo Xuan

Classifications

• H01S3/0811 Primary

  incorporating a dispersive element, e.g. a prism for wavelength selection · CPC title

• H01S3/136 Primary

  by controlling devices placed within the cavity · CPC title

• H01S3/10069

  Memorized or pre-programmed characteristics, e.g. look-up table [LUT] · CPC title

• H01S3/08059

  Constructional details of the reflector, e.g. shape (mirrors in general G02B5/08; mountings for mirrors G02B7/18) · CPC title

• H01S3/105

  by controlling the mutual position or the reflecting properties of the reflectors of the cavity {, e.g. by controlling the cavity length}({H01S3/10076}, H01S3/13 take precedence) · CPC title