US4711696A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for enhancing Ti:Al2 O3 tunable laser crystal fluorescence by controlling crystal growth atmosphere
Assignee: Union Carbide Corp
•
Filing: 1986-03-11
•
Granted: 1987-12-08
•
Expires: 2006-03-11
Abstract
Abstract Controlled growth atmosphere process for titanium doped tunable laser material to enhance lasing efficiency using carbon monoxide during melt formation.
Inventors
- 👤 Milan R. Kokta
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 10:41
CPC Classifications
C; C30; C30B; C30B15/00; C30B29/00; C30B29/10; C30B29/16; C30B29/20; Y; Y10; Y10S; Y10S117/00; Y10S117/906
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
123 words
A method for making a Ti doped Al 2 O 3 crystal suitable as a laser material comprising: (i) making a solid phase mixture of a doping amount of TiO 2 in Al 2 O 3 to provide a melt under a non-reactive atmosphere; (ii) introducing carbon monoxide into said non-reactive atmosphere while the melt is in the solid phase; (iii) purging said non-reactive atmosphere of carbon monoxide and its reactive gaseous products prior to liquifaction of said solid phase mixture; (iv) introducing a reducing agent other than carbon monoxide into said non-reactive atmosphere as a substitute for said carbon monoxide; and (v) heating said melt to a sufficiently high temperature under said non-reactive atmosphere to form a Ti:Al 2 O 3 crystal.
Claim 2
Independent Claim
123 words
A method for making a Ti doped Al 2 O 3 crystal suitable as a laser material comprising: (i) making a solid phase mixture of a doping amount of TiO 2 in Al 2 O 3 to provide a melt under a non-reactive atmosphere; (ii) introducing carbon monoxide into said non-reactive atmosphere while the melt is in the solid phase; (iii) purging said non-reactive atmosphere of carbon monoxide and its reactive gaseous products prior to liquifaction of said solid phase mixture; (iv) introducing a reducing agent other than carbon monoxide into said non-reactive atmosphere as a substitute for said carbon monoxide; and (v) heating said melt to a sufficiently high temperature under said non-reactive atmosphere to form a Ti:Al 2 O 3 crystal.
Claim 3
Dependent Claim
27 words
The method of claim 1 wherein said reducing agent in step (iv) includes H 2 in an amount sufficient to reduce free oxygen present at the melt.
Claim 4
Dependent Claim
35 words
The method of claim 3 wherein the crystal formed in step (v) is cooled and at least above a temperature of about 1600° C., the cooling crystal is maintained in a non-reactive atmosphere containing hydrogen.
Claim 5
Dependent Claim
26 words
The method of claim 3 wherein the TiO 2 is of high purity and the Al 2 O 3 contains less than 100 ppm of impurities.
Claim 6
Dependent Claim
20 words
The method of claim 1 wherein the melt is heated to a temperature of about 2050° C. to 2080° C.
Claim 7
Dependent Claim
14 words
The method of claim 5 wherein the crystal is formed by the Czochralski technique.
Claim 8
Dependent Claim
19 words
The method of claim 1 wherein the solid phase mixture contains from about 0.03 to 1.0 weight percent titanium.
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) | 1990-12-07 | 1991-06-08 | 1991-12-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-12-07 | 1995-06-08 | 1995-12-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-12-07 | 1999-06-08 | 1999-12-08 | $7700.00 | Window Closed / Lapsed |