US4236824A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for correction of forged optical elements
Assignee: Northrop Grumman Innovation Systems LLC
•
Filing: 1979-06-21
•
Granted: 1980-12-02
•
Expires: 1999-06-21
Abstract
Abstract The optical surface figures of both optical surfaces of a forged halide optical element can be corrected and optimized using an interferometer to observe the lens surface while applying pressure via gas to produce permanent deformation of the lens.
Inventors
- 👤 Rogers H. Anderson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 06:15
CPC Classifications
G; G01; G01B; G01B11/00; G01B11/24; G01B11/255
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
129 words
Apparatus for correction of forged halide optical elements comprising: an enclosed chamber for supporting a forged halide optical element within the chamber, the chamber having resilient gas tight sealing and support means for the optical element, the chamber having an opening therein for direct viewing of the optical element supported therein; means including controllable gas pressure regulator means for connecting a source of pressurized gas to said enclosed chamber so that a controllable gas pressure can be applied in said chamber, said gas pressure being thereby applied to the inner face of the supported optical element to cause deformation thereof to achieve a desired correction of said element; and, interferometer means positioned to view said optical element through said chamber opening to determine when the desired correction is achieved.
Claim 2
Dependent Claim
129 words
Apparatus for correction of forged halide optical elements comprising: an enclosed chamber for supporting a forged halide optical element within the chamber, the chamber having resilient gas tight sealing and support means for the optical element, the chamber having an opening therein for direct viewing of the optical element supported therein; means including controllable gas pressure regulator means for connecting a source of pressurized gas to said enclosed chamber so that a controllable gas pressure can be applied in said chamber, said gas pressure being thereby applied to the inner face of the supported optical element to cause deformation thereof to achieve a desired correction of said element; and, interferometer means positioned to view said optical element through said chamber opening to determine when the desired correction is achieved.
Claim 3
Dependent Claim
79 words
The apparatus according to claim 1 wherein said chamber comprises: an upper portion which is substantially disc shaped and has fastenable thereto in air tight relation a lower portion which is substantially cup shaped and which has said viewing opening located substantially axially in the bottom of said lower portion, with the remaining bottom as an inverted shoulder acting as a circular supporting ledge for said element, said ledge having said resilient gas tight sealing and support means therein.
Claim 4
Dependent Claim
15 words
The apparatus according to claim 1 wherein said interferometer means operates in the Fizeau mode.
Claim 5
Dependent Claim
15 words
The apparatus according to claim 1 wherein said interferometer means operates in the Twyman-Green mode.
Claim 6
Independent Claim
100 words
A method for correction of forged halide optical elements comprising the steps of: providing a halide optical element to be corrected; providing an optical element supporting chamber which chamber supports the optical element at its perimeter, said chamber being gas tight when said optical element is in place; providing a controllable source of gas pressure into said chamber to exert a controllable pressure on one face of said optical element to cause a controlled correction deformation of said element; and, providing an interferometer to view the surface of the optical element and determine when the desired correction has been obtained.
Claim 7
Independent Claim
100 words
A method for correction of forged halide optical elements comprising the steps of: providing a halide optical element to be corrected; providing an optical element supporting chamber which chamber supports the optical element at its perimeter, said chamber being gas tight when said optical element is in place; providing a controllable source of gas pressure into said chamber to exert a controllable pressure on one face of said optical element to cause a controlled correction deformation of said element; and, providing an interferometer to view the surface of the optical element and determine when the desired correction has been obtained.
Claim 8
Dependent Claim
25 words
The method according to claim 5 in which the optical element provided is selected from a group consisting of alkali halides and alkaline earth halides.
Claim 9
Dependent Claim
14 words
The method according to claim 5 in which the optical element provided is KBr.
Claim 10
Dependent Claim
22 words
The method according to claim 7 wherein the controllable pressure applied is in the range of about 25 to about 50 psi.
References Cited (Backward Citations)
US3693301A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-12-02 | 1984-06-02 | 1984-12-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-12-02 | 1988-06-02 | 1988-12-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-12-02 | 1992-06-02 | 1992-12-02 | $7700.00 | Window Closed / Lapsed |