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US4672619A
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Color centers for tunable lasers in the near infrared region
Assignee: University of Utah Research Foundation Inc
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Filing: 1982-05-18
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Granted: 1987-06-09
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Expires: 2002-05-18
Abstract
Abstract Stable color centers capable of laser emission in the near infrared region of the optical spectrum are provided in alkali halide host crystals containing monovalent heavy metal cation impurities such as thallium, gallium, indium, silver and copper. The laser active color centers are formed by exposing the crystal to ionizing radiation followed by irradiation with light having a wavelength absorbed by the F centers. The resulting material is capable of stable, broadly tunable laser operation with high power output in the near infrared region. Oscillation on a single mode can be easily obtained.
Inventors
- 👤 Fritz Luty
- 👤 Werner Gellermann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 20:30
CPC Classifications
H; H01; H01S; H01S3/00; H01S3/14; H01S3/16; H01S3/1681
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
84 words
An optical resonator for causing the stimulated emission of radiation comprising: a laser material having laser-active color centers which include at least one monovalent heavy metal cation impurity and at least one anion vacancy, each of said color centers having at least one electron associated therewith; means for exciting said laser-active color centers to an excited state; and an optical resonant cavity for holding the laser material and capable of resonating so as to stimulate the emission of coherent radiation from said color centers.
Claim 2
Dependent Claim
84 words
An optical resonator for causing the stimulated emission of radiation comprising: a laser material having laser-active color centers which include at least one monovalent heavy metal cation impurity and at least one anion vacancy, each of said color centers having at least one electron associated therewith; means for exciting said laser-active color centers to an excited state; and an optical resonant cavity for holding the laser material and capable of resonating so as to stimulate the emission of coherent radiation from said color centers.
Claim 3
Dependent Claim
32 words
An optical resonator as defined in claim 1 wherein the optical resonant cavity has a three-mirror, astigmatically compensated configuration and the laser material is located at the beam waist of said cavity.
Claim 4
Dependent Claim
20 words
An optical resonator as defined in claim 2 further comprising tuning means for tuning said emission from said color centers.
Claim 5
Dependent Claim
22 words
An optical resonator as defined in claim 3 wherein the tuning means is an optical grating rotatably mounted within the optical resonator.
Claim 6
Dependent Claim
85 words
A wavelength tunable laser comprising: a laser material having laser-active color centers which include at least one monovalent heavy metal cation impurity and at least one anion vacancy, each of said color center having at least one electron associated therewith; means for exciting said laser material to emit coherent radiation within the emission band of said laser material; and mirrors forming an optical resonator, said resonator enclosing the laser material and an optical grating for selecting a particular wavelength of said radiation within said resonator.
Claim 7
Dependent Claim
85 words
A wavelength tunable laser comprising: a laser material having laser-active color centers which include at least one monovalent heavy metal cation impurity and at least one anion vacancy, each of said color center having at least one electron associated therewith; means for exciting said laser material to emit coherent radiation within the emission band of said laser material; and mirrors forming an optical resonator, said resonator enclosing the laser material and an optical grating for selecting a particular wavelength of said radiation within said resonator.
Claim 8
Dependent Claim
20 words
A wavelength tunable laser as defined in claim 5 wherein the optical grating is rotatably mounted within the optical resonator.
Claim 9
Independent Claim
68 words
A method for generating color centers capable of laser activity, said method comprising the steps of: forming a crystal comprised of an alkali halide doped with monovalent heavy metal cation impurities; exposing said crystal to ionizing radiation so as to form F centers; and irradiating said crystal with light having at least one wavelength absorbed by the F centers, thereby aggregating the F centers with the cation impurities.
Claim 10
Independent Claim
68 words
A method for generating color centers capable of laser activity, said method comprising the steps of: forming a crystal comprised of an alkali halide doped with monovalent heavy metal cation impurities; exposing said crystal to ionizing radiation so as to form F centers; and irradiating said crystal with light having at least one wavelength absorbed by the F centers, thereby aggregating the F centers with the cation impurities.
Claim 11
Dependent Claim
32 words
A method for generating color centers as defined in claim 7 wherein the alkali halide crystal is selected from the group consisting of sodium chloride, potassium chloride, potassium bromide, and rubidium chloride.
Claim 12
Dependent Claim
30 words
A method for generating color centers as defined in claim 7 wherein the alkali of the alkali halide crystal is selected from the group consisting of sodium, potassium, and rubidium.
Claim 13
Dependent Claim
31 words
A method for generating color centers as defined in claim 9 wherein the halide of the alkali halide crystal is selected from the group consisting of fluoride, chloride, bromide, and iodide.
Claim 14
Dependent Claim
31 words
A method for generating color centers as defined in claim 7 wherein the halide of the alkali halide crystal is selected from the group consisting of fluoride, chloride, bromide, and iodide.
Claim 15
Dependent Claim
35 words
A method for generating color centers as defined in claim 7 wherein the concentration of the cation impurities in the alkali halide cyrstal is in the range of about 0.05 to about 0.5 mole percent.
Claim 16
Dependent Claim
17 words
A method for generating color centers as defined in claim 7 wherein the cation impurity is thallium.
Claim 17
Dependent Claim
33 words
A method for generating color centers as defined in claim 13 wherein the alkali halide host crystal is selected from the group consisting of sodium chloride, potassium chloride, potassium bromide, and rubidium chloride.
Claim 18
Dependent Claim
31 words
A method for generating color centers as defined in claim 13 wherein the alkali of the alkali halide host crystal is selected from the group consisting of sodium, potassium, and rubidium.
Claim 19
Dependent Claim
32 words
A method for generating color centers as defined in claim 15 wherein the halide of the alkali halide host crystal is selected from the group consisting of fluoride, chloride, bromide, and iodide.
Claim 20
Dependent Claim
32 words
A method for generating color centers as defined in claim 13 wherein the halide of the alkali halide host crystal is selected from the group consisting of fluoride, chloride, bromide, and iodide.
Claim 21
Dependent Claim
30 words
A method for generating color centers as defined in claim 13 wherein the concentration of thallium impurity cations is in the range of about 0.05 to about 0.5 mole percent.
Claim 22
Dependent Claim
17 words
A method for generating color centers as defined in claim 7 wherein the cation impurity is gallium.
Claim 23
Dependent Claim
17 words
A method for generating color centers as defined in claim 7 wherein the cation impurity is indium.
Claim 24
Dependent Claim
17 words
A method for generating color centers as defined in claim 7 wherein the cation impurity is silver.
Claim 25
Dependent Claim
17 words
A method for generating color centers as defined in claim 7 wherein the cation impurity is copper.
Claim 26
Dependent Claim
29 words
A method for generating color centers as defined in claim 7 wherein the crystal is exposed to ionizing radiation at a crystal temperature at which anion vacancies can diffuse.
Claim 27
Dependent Claim
66 words
A method for generating color centers as defined in claim 7 wherein the crystal is exposed to ionizing radiation at a crystal temperature below that at which anion vacancies can diffuse, and further comprising the step of warming the crystal to a temperature at which anion vacancies can diffuse prior to irradiating the crystal with light having at least one wavelength absorbed by the F centers.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-06-08 | 1990-12-08 | 1991-06-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-06-08 | 1994-12-08 | 1995-06-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-06-08 | 1998-12-08 | 1999-06-09 | $7700.00 | Window Closed / Lapsed |