US4688893A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hollow waveguide having plural layer dielectric
Assignee: ESC MEDICAL SYSTEMS Inc
•
Filing: 1985-03-18
•
Granted: 1987-08-25
•
Expires: 2005-03-18
Abstract
Abstract A hollow waveguide has an inner reflective layer such as silver, overcoated with plural layers of dielectric. Preferably three dielectric layers are used, with the inner two having quarter wave thickness, and the outer one having one half on one and one half the quarter wave thickness. Compositions for the dielectric include ThF 4 /Ge/ThF 4 , ZnSe/Ge/ZnSe, Ge/ThF 4 /Ge, and ThF 4 /ZnSe/ThF 4 .
Inventors
- 👤 Katherine D. Laakmann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 05:18
CPC Classifications
G; G02; G02B; G02B6/00; G02B6/02; G02B6/032; G02B6/10
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
107 words
A flexible hollow waveguide for high efficiency transmission of CO 2 laser light which comprises: (a) a guide having an internal surface and an external cross section sufficiently small to allow for endoscopic application; (b) a metal coating applied to the internal surface of said metal guide, said coating characterized by a high degree of reflectivity of light at normal incidence for the waveglength of use; (c) a plural layer dielectric coating applied to said metal coating, said coating composite having the reflectivities of the P and S polarization averaged together to be in excess of 98.5% for all angles of incidence ranging from 80° to 90°.
Claim 2
Dependent Claim
107 words
A flexible hollow waveguide for high efficiency transmission of CO 2 laser light which comprises: (a) a guide having an internal surface and an external cross section sufficiently small to allow for endoscopic application; (b) a metal coating applied to the internal surface of said metal guide, said coating characterized by a high degree of reflectivity of light at normal incidence for the waveglength of use; (c) a plural layer dielectric coating applied to said metal coating, said coating composite having the reflectivities of the P and S polarization averaged together to be in excess of 98.5% for all angles of incidence ranging from 80° to 90°.
Claim 3
Dependent Claim
20 words
The hollow waveguide according to claim 1 wherein said guide is made of aluminum and said metal coating is silver.
Claim 4
Dependent Claim
19 words
The hollow metal waveguide according to claim 1 wherein the interior cross section of the waveguide is square shaped.
Claim 5
Dependent Claim
18 words
The hollow metal waveguide according to claim 1 wherein the interior cross section of the waveguide is circular.
Claim 6
Dependent Claim
36 words
A waveguide as described in claim 1 and comprising three said layers of dielectric, first and third ones of which being a first dielectric material, and a middle one of which being a second dielectric material.
Claim 7
Dependent Claim
33 words
A waveguide as described in claim 5 wherein said first dielectric material has an index of refraction which is relatively low in comparison with the index of refraction of said second dielectric material.
Claim 8
Dependent Claim
30 words
The hollow waveguide according to claim 5 wherein the first and third layers are ThF 4 and the second laver is selected from the group consisting of ZnSe and Ge.
Claim 9
Dependent Claim
21 words
The hollow waveguide according to claim 5 wherein the first and third layers are ZnSe and the second coating is Ge.
Claim 10
Dependent Claim
23 words
The hollow waveguide according to claim 5 wherein said first and third layers are Ge and the second layer is ThF 4 .
Claim 11
Dependent Claim
31 words
A waveguide as described in claim 5 wherein said outermost of said dielectric layers has a thickness between approximately one-eighth and three-eighth of the wavelength of light in said outermost layer.
References Cited (Backward Citations)
US3436141A
Cited
US4068920A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-08-24 | 1991-02-23 | 1991-08-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-08-24 | 1995-02-23 | 1995-08-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-08-24 | 1999-02-23 | 1999-08-25 | $7700.00 | Window Closed / Lapsed |