US3914023A
Expired / Lapsed
US
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Wide-band multilayer interference filter
Assignee: Balzers Patent und Beteiligungs AG
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Filing: 1973-12-05
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Granted: 1975-10-21
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Expires: 1993-12-05
Abstract
Abstract A wide-band multilayer interference filter comprises a filter having a periodic arrangement of layers of the structure ABCDDCBA, where A,B,C,D indicate individual layers having each an optical thickness of one-fourth of the predetermined constructional wavelength and the mutually different refraction indices of said layers fulfill the following conditions:
Inventors
- 👤 Alfred Thelen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 17:10
CPC Classifications
G; G02; G02B; G02B5/00; G02B5/20; G02B5/28; G02B5/285; C; C09; C09K; C09K2323/00; C09K2323/03; C09K2323/031; C09K2323/033
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
79 words
A wide-band multilayer interference filter in which the stopbands of higher order are partly suppressed, comprising a filter having a periodic arrangement of layers of the structure ABCDDCBA, where A,B,C,D indicate individual layers having each an optical thickness of one-fourth of the predetermined constructional wavelength and the mutually different refraction indices of said layers fulfill the following conditions: y2 - 2y. x2 - x + 1/x + 1 0 where x nA/nB y nB/nC and nA nD nB nC
Claim 2
Dependent Claim
79 words
A wide-band multilayer interference filter in which the stopbands of higher order are partly suppressed, comprising a filter having a periodic arrangement of layers of the structure ABCDDCBA, where A,B,C,D indicate individual layers having each an optical thickness of one-fourth of the predetermined constructional wavelength and the mutually different refraction indices of said layers fulfill the following conditions: y2 - 2y. x2 - x + 1/x + 1 0 where x nA/nB y nB/nC and nA nD nB nC
Claim 3
Dependent Claim
23 words
A wide-band multilayer interference filter according to claim 1, wherein the stRuctural sequence ABCDDCBA in the layer system recurrs at least three times.
Claim 4
Dependent Claim
25 words
A wide-band multilayer interference filter according to claim 1, wherein the refractive indices of the layers are: nA 1.46 nB 1.68 nC 2.04 nD 2.35
Claim 5
Dependent Claim
25 words
A wide-band multilayer interference filter according to claim 1, wherein the refractive indices of the layers are: nA 1.38 nB 1.55 nC 1.83 nD 2.05
Claim 6
Dependent Claim
25 words
A wide-band multilayer interference filter according to claim 1, wherein the refractive indices of the layers are: nA 1.80 nB 2.31 nC 3.28 nD 4.20.
Claim 7
Dependent Claim
38 words
A wide-band multilayer interference filter according to claim 1, wherein the layers A are made of SiO2, the layers B are made of Al2O3, the layers C are made of ZrO2, the layers D are made of TiO2.
Claim 8
Dependent Claim
38 words
A wide-band multilayer interference filter according to claim 1, wherein the layers A are made of MgF2, the layers B are made of ThF4, the layers C are made of La2O3, the layers D are made of ZrO2.
Claim 9
Dependent Claim
39 words
A wide-band multilayer interference filter according to claim 1, wherein the layers A are made of SiO2, the layers B are made of ZnS, the layers C are made of Si, and the layers D are made of Ge.
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) | 1978-10-20 | 1979-04-21 | 1979-10-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-10-20 | 1983-04-21 | 1983-10-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-10-20 | 1987-04-21 | 1987-10-21 | $7700.00 | Window Closed / Lapsed |