US5020073A
Expired / Lapsed
US
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Apparatus for aligning the optic axis of an intra-cavity birefringent element, and tunable laser using same
Assignee: CDC ACQUISITION CORP
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Filing: 1989-03-07
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Granted: 1991-05-28
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Expires: 2009-03-07
Abstract
Abstract Alignment of a birefringent tunable laser gain medium characterized by a first face and a second face cut at Brewster's angle so that a plane of polarization is defined. The gain medium is secured in the optical path by a rotatable member having an axis of rotation that is normal to the Brewster faces of the optical device. Coupled with the rotatable member is a support allowing adjustment of the angular position about the axis of rotation fo the rotatable member. An operator adjusts the angular position of the rotatable member until the C-axis of the gain medium lies in the plane of polarization. Even though the C-axis may not be parallel to the direction of polarization, the depolarization effects of the misalignment are eliminated by proper adjustment of the angular position relative to the plane of polarization. A tunable, solid state laser using the alignment apparatus with a birefringent filter achieves greater linear tuning range.
Inventors
- 👤 Anthony J. Alfrey
- 👤 James A. Palmer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 13:27
CPC Classifications
H; H01; H01S; H01S3/00; H01S3/10; H01S3/106; H01S3/05; H01S3/08; H01S3/081
Claims Analysis
Total Claims: 39
Claim 1
Independent Claim
115 words
An apparatus for aligning a laser gain medium in an optical path, the gain medium having a first face and a second face, at least one of the first and second faces at Brewster's angle so that a plane of polarization is defined, comprising: rotatable means, having an axis of rotation and an adjustable angular position about the axis of rotation, for securing the gain medium in the optical path so that the optical path intersects the first and second faces, and wherein the axis of rotation is normal to the one face at Brewster's angle; and means, connected to the rotatable means, for adjusting the adjustable angular position relative to the plane of polarization.
Claim 2
Independent Claim
115 words
An apparatus for aligning a laser gain medium in an optical path, the gain medium having a first face and a second face, at least one of the first and second faces at Brewster's angle so that a plane of polarization is defined, comprising: rotatable means, having an axis of rotation and an adjustable angular position about the axis of rotation, for securing the gain medium in the optical path so that the optical path intersects the first and second faces, and wherein the axis of rotation is normal to the one face at Brewster's angle; and means, connected to the rotatable means, for adjusting the adjustable angular position relative to the plane of polarization.
Claim 3
Dependent Claim
11 words
The apparatus of claim 1, wherein the gain medium is birefringent.
Claim 4
Dependent Claim
13 words
The apparatus of claim 1, wherein the gain medium includes an anisotropic crystal.
Claim 5
Dependent Claim
11 words
The apparatus of claim 1, wherein the gain medium is rod-shaped.
Claim 6
Dependent Claim
40 words
The apparatus of claim 1, wherein the gain medium is a crystal of titanium sapphire having a C-axis, and the C-axis lies in a plane having an angular position about the axis of rotation determined by the adjustable angular position.
Claim 7
Dependent Claim
90 words
The apparatus of claim 1, wherein the rotatable means includes: a cylindrical member having a first end, a second end, and a longitudinal axis, the longitudinal axis being the axis of rotation, and the first and second ends being normal to the longitudinal axis, the cylindrical member further having a passage from the first end to the second end, the gain medium being secured within the passage so that the first face and the second face are parallel to the first end and second end, respectively, of the cylindrical member.
Claim 8
Dependent Claim
34 words
The apparatus of claim 6, wherein the means for adjusting includes: a guide for supporting the cylindrical member so that the optical path traverses the gain medium while permitting rotation about the longitudinal axis.
Claim 9
Dependent Claim
36 words
The apparatus of claim 7, wherein the cylindrical member and the guide are formed of heat conducting material, and further including: means, coupled to the guide, for flowing a cooling medium in contact with the guide.
Claim 10
Independent Claim
150 words
An apparatus for aligning a laser gain medium in an optical path, the gain medium having a first face and a second face, at least one of the first and second faces at Brewster's angle so that a plane of polarization is defined, comprising: rotatable means, having an axis of rotation and an adjustable angular position about the axis of rotation relative to the plane of polarization, for securing the gain medium in the optical path so that the optical path intersects the first and second faces, and wherein the axis of rotation is normal to the one face at Brewster's angle; and means, connected to the rotatable means, for adjusting the adjustable angular position relative to the plane of polarization wherein the means for adjusting includes: a guide for supporting the rotatable means so that the optical path traverses the gain-medium while permitting rotation about the axis of rotation.
Claim 11
Independent Claim
150 words
An apparatus for aligning a laser gain medium in an optical path, the gain medium having a first face and a second face, at least one of the first and second faces at Brewster's angle so that a plane of polarization is defined, comprising: rotatable means, having an axis of rotation and an adjustable angular position about the axis of rotation relative to the plane of polarization, for securing the gain medium in the optical path so that the optical path intersects the first and second faces, and wherein the axis of rotation is normal to the one face at Brewster's angle; and means, connected to the rotatable means, for adjusting the adjustable angular position relative to the plane of polarization wherein the means for adjusting includes: a guide for supporting the rotatable means so that the optical path traverses the gain-medium while permitting rotation about the axis of rotation.
Claim 12
Dependent Claim
46 words
The apparatus of claim 9, wherein the rotatable means and the guide comprise heat conducting material so that heat may flow from the gain medium to the guide, and further including: means, coupled to the guide, for flowing a cooling medium in contact with the guide.
Claim 13
Independent Claim
113 words
An apparatus for generating a laser beam at an operating frequency, comprising: a laser cavity defining an optical path; a birefringent filter mounted within the laser cavity along the optical path; a birefringent device having a crystallographic axis lying in a first plane, the birefringent device and the birefringent filter cooperatively affecting the operating frequency, the birefringent device having a first face and a second face out at Brewster's angle so that a plane of polarization is defined and having a direction of propagation extending between the first and second faces; means for securing the birefringent device in the optical path so that the first plane is parallel to the plane of polarization.
Claim 14
Independent Claim
113 words
An apparatus for generating a laser beam at an operating frequency, comprising: a laser cavity defining an optical path; a birefringent filter mounted within the laser cavity along the optical path; a birefringent device having a crystallographic axis lying in a first plane, the birefringent device and the birefringent filter cooperatively affecting the operating frequency, the birefringent device having a first face and a second face out at Brewster's angle so that a plane of polarization is defined and having a direction of propagation extending between the first and second faces; means for securing the birefringent device in the optical path so that the first plane is parallel to the plane of polarization.
Claim 15
Dependent Claim
13 words
The apparatus of claim 12, wherein the birefringent device includes an anisotropic crystal.
Claim 16
Dependent Claim
15 words
The apparatus of claim 11, wherein the birefringent device is a rod-shaped laser gain medium.
Claim 17
Dependent Claim
15 words
The apparatus of claim 11, wherein the birefringent device is a tunable laser gain medium.
Claim 18
Dependent Claim
25 words
The apparatus of claim 11, wherein the birefringent device is a crystal of titanium sapphire having a C-axis, and the C-axis is the crystallographic axis.
Claim 19
Independent Claim
135 words
An apparatus for generating a laser beam, comprising: an optical resonant cavity defining an optical path; a birefringent filter mounted within the resonant cavity along the optical path; a gain medium, the gain medium having a first face and a second face at Brewster's angle so that a plane of polarization is defined; rotatable means, having an axis of rotation, for securing the gain medium in the optical path so that the axis of rotation is normal to the first face and the rotatable means has an adjustable angular position about the axis of rotation; means, connected to the rotatable means, for adjusting the adjustable angular position; and means, coupled with the resonant activity, for supplying a pump energy bean longitudinally into the gain medium through at least one of the first and second faces.
Claim 20
Independent Claim
135 words
An apparatus for generating a laser beam, comprising: an optical resonant cavity defining an optical path; a birefringent filter mounted within the resonant cavity along the optical path; a gain medium, the gain medium having a first face and a second face at Brewster's angle so that a plane of polarization is defined; rotatable means, having an axis of rotation, for securing the gain medium in the optical path so that the axis of rotation is normal to the first face and the rotatable means has an adjustable angular position about the axis of rotation; means, connected to the rotatable means, for adjusting the adjustable angular position; and means, coupled with the resonant activity, for supplying a pump energy bean longitudinally into the gain medium through at least one of the first and second faces.
Claim 21
Dependent Claim
38 words
The apparatus of claim 16, wherein the gain medium includes an anisotropic crystal having a C-axis, and the C-axis lies in a plane having an angular position about the axis of rotation determined by the adjustable angular position.
Claim 22
Dependent Claim
11 words
The apparatus of claim 16, wherein the gain medium is rod-shaped.
Claim 23
Dependent Claim
39 words
The apparatus of claim 16, wherein the gain medium is crystal of titanium sapphire having a C-axis, and the C-axis lies in a plane having an angular position about the axis of rotation determined by the adjustable angular position.
Claim 24
Dependent Claim
90 words
The apparatus of claim 16, wherein the rotatable means includes: a cylindrical member having a first end, a second end, and a longitudinal axis, the longitudinal axis being the axis of rotation, and the first and second ends being normal to the longitudinal axis, the cylindrical member further having a passage from the first end to the second end, the gain medium being secured within the passage so that the first face and the second face are parallel to the first end and second end, respectively, of the cylindrical member.
Claim 25
Dependent Claim
34 words
The apparatus of claim 20, wherein the means for adjusting includes: a guide for supporting the cylindrical member so that the optical path traverses the gain medium while permitting rotation about the longitudinal axis.
Claim 26
Dependent Claim
36 words
The apparatus of claim 21, wherein the cylindrical member and the guide are formed of heat conducting material, and further including: means, coupled to the guide, for flowing a cooling medium in contact with the guide.
Claim 27
Dependent Claim
35 words
The apparatus of claim 16, wherein the means for adjusting includes: a guide for supporting the rotatable means so that the optical path traverses the gain medium while permitting rotation about the axis of rotation.
Claim 28
Dependent Claim
48 words
The apparatus of claim 23, wherein the rotatable means and the guide are formed of heat conducting material so that heat may flow from the gain medium to the guide, and further including: means, coupled to the guide, for flowing a cooling medium in contact with the guide.
Claim 29
Independent Claim
173 words
An apparatus for generating a laser beam, comprising: an optical resonant cavity defining an optical path; tunable means, mounted within the resonant cavity, for tuning the resonant cavity to select a longitudinal mode; a gain medium comprising an anisotropic crystalline material having a crystalline axis and capable of supporting laser gain over a range of wavelengths, the gain medium having a first face and a second face at Brewster's angle so that a plane of polarization is defined; rotatable means, having an axis of rotation, for securing the gain medium in the optical path so that the axis of rotation is normal to the first face and the rotatable means has an adjustable angular position about the axis of rotation; means, connected to the rotatable means, for adjusting the adjustable angular position in order to align the crystalline axis essentially within the plane of polarization; and means, coupled with the resonant activity, for supplying a pump energy beam longitudinally into the gain medium through at least one of the first and second faces.
Claim 30
Independent Claim
173 words
An apparatus for generating a laser beam, comprising: an optical resonant cavity defining an optical path; tunable means, mounted within the resonant cavity, for tuning the resonant cavity to select a longitudinal mode; a gain medium comprising an anisotropic crystalline material having a crystalline axis and capable of supporting laser gain over a range of wavelengths, the gain medium having a first face and a second face at Brewster's angle so that a plane of polarization is defined; rotatable means, having an axis of rotation, for securing the gain medium in the optical path so that the axis of rotation is normal to the first face and the rotatable means has an adjustable angular position about the axis of rotation; means, connected to the rotatable means, for adjusting the adjustable angular position in order to align the crystalline axis essentially within the plane of polarization; and means, coupled with the resonant activity, for supplying a pump energy beam longitudinally into the gain medium through at least one of the first and second faces.
Claim 31
Dependent Claim
23 words
The apparatus of claim 25, further including: means, in heat flow communication with the gain medium, for controlling temperature of the gain medium.
Claim 32
Dependent Claim
11 words
The apparatus of claim 25, wherein the gain medium is rod-shaped.
Claim 33
Dependent Claim
11 words
The apparatus of claim 25, wherein the gain medium comprises titanium:sapphire.
Claim 34
Dependent Claim
90 words
The apparatus of claim 25, wherein the rotatable means includes: a cylindrical member having a first end, a second end, and a longitudinal axis, the longitudinal axis being the axis of rotation, and the first and second ends being normal to the longitudinal axis, the cylindrical member further having a passage from the first end to the second end, the gain medium being secured within the passage so that the first face and the second face are parallel to the first end and second end, respectively, of the cylindrical member.
Claim 35
Dependent Claim
34 words
The apparatus of claim 29, wherein the means for adjusting includes: a guide for supporting the cylindrical member so that the optical path traverses the gain medium while permitting rotation about the longitudinal axis.
Claim 36
Dependent Claim
37 words
The apparatus of claim 30, wherein the cylindrical member and the guide are formed of heat conducting material, and further including: means, coupled to the guide, for flowing a heat transfer medium in contact with the guide.
Claim 37
Dependent Claim
35 words
The apparatus of claim 25, wherein the means for adjusting includes: a guide for supporting the rotatable means so that the optical path traverses the gain medium while permitting rotation about the axis of rotation.
Claim 38
Dependent Claim
52 words
The apparatus of claim 25, wherein the rotatable means comprises heat conducting material so that heat may flow from the gain medium to the rotatable means, and further including: means, in heat flow communication with the rotatable means, for flowing a heat transfer medium in heat flow communication with the rotatable means.
Claim 39
Dependent Claim
14 words
The apparatus of claim 25, wherein the axis of rotation intersects the gain medium.
References Cited (Backward Citations)
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1994-05-27 | 1994-11-26 | 1995-05-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-05-27 | 1998-11-26 | 1999-05-28 | $3760.00 | Window Closed / Lapsed |
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