US4947402A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Two-mirror shaping of a non-circular optical pumping beam and lasers using same
Assignee: Viavi Solutions Inc
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Filing: 1988-04-25
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Granted: 1990-08-07
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Expires: 2008-04-25
Abstract
Abstract In a laser, the laser gain member is optically pumped by a semiconductive source of pumping radiation having an elongated output beam aperture such as that provided by a single-wide stripe diode or diode array. The elongated beam of optical pumping radiation is twice reflected from a concave surface at non-normal angles of incidence and then focused onto the laser gain material for pumping same. The reflections serve to differentially focus rays diverging in the vertical plane from rays diverging in the horizontal plane to shape the pumping beam for improved pumping efficiency in the pumped mode volume of the laser gain material. In a preferred embodiment, a magnifying lens is disposed inbetween the source and the reflectors for decreasing the divergence of the pumping beam.
Inventors
- 👤 Thomas J. Kane
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 02:47
CPC Classifications
G; G02; G02B; G02B19/00; G02B19/0033; G02B19/0047; G02B19/0052; G02B19/0057; G02B19/0004; G02B19/0028; G02B27/00; G02B27/09; G02B27/0938; G02B27/0977; G02B27/0983; H; H01; H01S; H01S3/00; H01S3/005; H01S3/09; H01S3/091; H01S3/094; H01S3/0941; H01S3/09415
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
120 words
A method of shaping a beam of light rays emanated from a horizontally elongated source, to pump a laser gain medium, comprising the steps of: reflecting said beam in a first reflection off a mirror having a horizontally concave surface at a non-normal angle in the plane of incidence, and reflecting said beam in a second reflection off a mirror having a horizontally concave surface at a non-normal angle in the plane of incidence, to de-magnify the horizontal dimension of the beam relative to its vertical dimension and thereby differentially focus rays in the horizontal and vertical planes to reduce the degree of elongation of the source image to improve laser pumping efficiency and gain at said laser gain medium.
Claim 2
Independent Claim
120 words
A method of shaping a beam of light rays emanated from a horizontally elongated source, to pump a laser gain medium, comprising the steps of: reflecting said beam in a first reflection off a mirror having a horizontally concave surface at a non-normal angle in the plane of incidence, and reflecting said beam in a second reflection off a mirror having a horizontally concave surface at a non-normal angle in the plane of incidence, to de-magnify the horizontal dimension of the beam relative to its vertical dimension and thereby differentially focus rays in the horizontal and vertical planes to reduce the degree of elongation of the source image to improve laser pumping efficiency and gain at said laser gain medium.
Claim 3
Dependent Claim
41 words
The method of claim 1 wherein: said first reflection focuses vertically divergent rays of the beam towards a first vertical focal point beyond the second reflection and focuses horizontally divergent rays to a first horizontal focal point before the second reflection.
Claim 4
Dependent Claim
60 words
The method of claim 2 wherein: in said second reflection, vertically divergent once-focused rays are re-focused to a second vertical focal point having a depth of focus in said laser gain medium, and horizontally-divergent once-focused rays are refocussed to a second horizontal focal point having a depth of focus overlapping said vertical depth of focus in said laser gain medium.
Claim 5
Dependent Claim
61 words
The method of claim 1 including the step of: using a lens having a power to gather rays emanated from said source and to focus gathered rays to a magnified source image which is then shaped through said first and second reflections onto the laser gain medium so that the lens power multiplies the magnification of the first and second reflections.
Claim 6
Dependent Claim
37 words
The method of claim 1 wherein said steps of reflecting said beam use two substantially identical spherical mirrors oriented with their axes in said horizontal plane at substantially identical 45 degree angles to the incident beam axis.
Claim 7
Dependent Claim
80 words
An imaging apparatus for shaping a beam of light rays emanated from a horizontally elongated source to pump a laser gain medium, comprising: reflecting means for convergently reflecting said beam in first and second reflections at non-normal angles of incidence in its horizontal dimension, said means including two mirrors, at least one of which is horizontally convergent, to differentially focus said beam in its vertical and horizontal planes and thereby improve the shape of said beam for more efficient pumping.
Claim 8
Dependent Claim
80 words
An imaging apparatus for shaping a beam of light rays emanated from a horizontally elongated source to pump a laser gain medium, comprising: reflecting means for convergently reflecting said beam in first and second reflections at non-normal angles of incidence in its horizontal dimension, said means including two mirrors, at least one of which is horizontally convergent, to differentially focus said beam in its vertical and horizontal planes and thereby improve the shape of said beam for more efficient pumping.
Claim 9
Dependent Claim
57 words
The apparatus of claim 6 wherein: said first reflection focuses rays diverging in the vertical plane to a first vertical focal point beyond the point of axial incidence of the second reflection, and to focus rays diverging in the horizontal plane to a first horizontal focal point before the point of axial incidence of the second reflection.
Claim 10
Dependent Claim
24 words
The apparatus of claim 7 wherein: said second reflection focuses rays diverging in both said vertical and horizontal planes onto the laser gain medium.
Claim 11
Dependent Claim
51 words
The apparatus of claim 6 including: lens means for gathering rays of optical pumping radiation emanating from said elongated source and for focusing gathered rays to a magnified source image for shaping by said reflecting means so that the power of said lens means multiplies the magnification of the reflecting means.
Claim 12
Dependent Claim
28 words
The apparatus of claim 6 wherein: said reflecting means comprises a pair of substantially spherically concave reflectors and wherein said non-normal angles of incidence are generally 45 degrees.
Claim 13
Dependent Claim
88 words
A laser comprising: a semiconductor diode source of optical pumping radiation having an elongated output aperture; a first horizontally concave mirror disposed to receive at a non-normal angle of horizontal incidence and to reflect optical pumping radiation emanated from said output aperture; a second horizontally concave mirror disposed to receive at a non-normal angle of incidence said optical pumping radiation after reflection off said first concave mirror; and a laser gain material disposed to receive optical pumping radiation as reflected from said second mirror, for being optically pumped.
Claim 14
Dependent Claim
88 words
A laser comprising: a semiconductor diode source of optical pumping radiation having an elongated output aperture; a first horizontally concave mirror disposed to receive at a non-normal angle of horizontal incidence and to reflect optical pumping radiation emanated from said output aperture; a second horizontally concave mirror disposed to receive at a non-normal angle of incidence said optical pumping radiation after reflection off said first concave mirror; and a laser gain material disposed to receive optical pumping radiation as reflected from said second mirror, for being optically pumped.
Claim 15
Dependent Claim
15 words
The laser of claim 11 wherein said first and second concave mirrors are substantially spherical.
Claim 16
Dependent Claim
22 words
The laser of claim 12 wherein the horizontal angles of incidence for said first and second mirrors are both substantially 45 degrees.
Claim 17
Dependent Claim
35 words
The laser of claim 11 including a magnifying lens disposed in the path of said beam between said semiconductive diode source and said first concave mirror for magnifying the image of the output beam aperture.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-08-06 | 1994-02-05 | 1994-08-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-08-06 | 1998-02-05 | 1998-08-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-08-06 | 2002-02-05 | 2002-08-07 | $7700.00 | Window Closed / Lapsed |