Patent US3604784A successfully refreshed from Google Patents.
US3604784A
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US
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Antireflection coatings
Assignee: Bausch and Lomb Inc
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Filing: 1969-01-21
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Granted: 1971-09-14
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Expires: 1989-01-21
Abstract
Abstract An antireflection coating for a light-reflecting substrate substitute three layers. Thickness of the layer adjacent the substrate is effectively one-quarter or one-half wavelength in optical thickness depending upon the index of refraction of the substrate. The middle layer is effectively one-half wavelength in optical thickness comprising a mixture of metallic oxides and the third layer is effectively one-quarter wavelength in optical thickness. A method of applying the middle layer of the coating employs directing a stream of oxygen at an electron beam which is directed at a source of coating material.
Inventors
- 👤 Anthony W Louderback
- 👤 Morris A Zook Jr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 13:47
CPC Classifications
G; G02; G02B; G02B1/00; G02B1/10; G02B1/11; G02B1/113; G02B1/115; C; C23; C23C; C23C14/00; C23C14/0021
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
114 words
A nonabsorbing substantially colorless multilayer antireflecting coating for use on a substrate having lightreflecting surfaces and an index of refraction of between 1.68 and 1.88, comprising: a first layer deposited on the substrate of a metallic oxide having an index of refraction of 1.64 to 1.72 and an effective optical thickness of one-half of a design wavelength; a second layer deposited on the first layer of a mixture of at least two metallic oxides having an index of refraction of about 2.00, effectively one-half of the design wavelength in optical thickness; and a third layer deposited on the second layer of magnesium fluoride having an effective optical thickness of one-quarter of the design wavelength.
Claim 2
Dependent Claim
114 words
A nonabsorbing substantially colorless multilayer antireflecting coating for use on a substrate having lightreflecting surfaces and an index of refraction of between 1.68 and 1.88, comprising: a first layer deposited on the substrate of a metallic oxide having an index of refraction of 1.64 to 1.72 and an effective optical thickness of one-half of a design wavelength; a second layer deposited on the first layer of a mixture of at least two metallic oxides having an index of refraction of about 2.00, effectively one-half of the design wavelength in optical thickness; and a third layer deposited on the second layer of magnesium fluoride having an effective optical thickness of one-quarter of the design wavelength.
Claim 3
Dependent Claim
21 words
The coating according to claim 1, wherein the second layer consists of a mixture of aluminum oxide and oxides of titanium.
Claim 4
Dependent Claim
34 words
The coating according to claim 1, wherein the index of refraction of the substrate is between 1.68 and 1.78 and the first layer is aluminum oxide having an index of refraction of approximately 1.64.
Claim 5
Dependent Claim
34 words
The coating according to claim 1, wherein the index of refraction of the substrate is between 1.78 and 1.88 and the first layer is magnesium oxide having an index of refraction of about 1.72.
Claim 6
Dependent Claim
13 words
The coating according to claim 1, wherein the design wavelength if 510 nanometers.
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) | 1974-09-13 | 1975-03-15 | 1975-09-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-09-13 | 1979-03-15 | 1979-09-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-09-13 | 1983-03-15 | 1983-09-14 | $7700.00 | Window Closed / Lapsed |