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Patent US4921760A successfully refreshed from Google Patents.
US4921760A
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Anti-reflection coating of optical part made of synthetic resin
Assignee: Minolta Co Ltd
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Filing: 1987-09-25
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Granted: 1990-05-01
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Expires: 2007-09-25
Abstract
Abstract An anti-reflection coating with n layers on an optical part substrate made of synthetic resin wherein n is 3, 4, or 5, and the first layer at the air side comprises silicon dioxide (SiO 2 ), and the n-th layer on the surface of the synthetic resin comprises ceric oxide (CeO 2 ) is excellent in reflection reducing effect and does not result in the age-based change of the refractive index. And that the very good adhesion of the reflection reducing coating with the substrate results in hardness of layer stripping. Further an anti-reflection coating of the invention has reflection reducing effect in the near-infrared region.
Inventors
- 👤 Hakuzo Tani
- 👤 Masaru Okumura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 03:33
CPC Classifications
G; G02; G02B; G02B1/00; G02B1/10; G02B1/11; G02B1/113; G02B1/115
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
132 words
An anti-reflection coating of three layers for a synthetic resin substrate having a refractive index in the approximate range of 1.49 to 1.58, comprising: a first layer, at the air side, of silicon dioxide; a second layer having an index of refraction of n 2 ; a third layer, adjacent the substrate, of ceric oxide, having an index of refraction of n 3 , and the second layer and the third layer satisfying the following conditions, respectively: 1.50≦n 2 ≦1.62, 0.04λ 0 ≦n 2 d 2 ≦0.15λ 0 , 1.92≦n 3 ≦2.10, 0.02λ 0 ≦n 3 d 3 ≦0.50λ 0 , wherein n 2 d 2 and n 3 d 3 are the optical thickness of the second layer and the third layer, respectively, and λ 0 is the dominant design wavelength.
Claim 2
Dependent Claim
132 words
An anti-reflection coating of three layers for a synthetic resin substrate having a refractive index in the approximate range of 1.49 to 1.58, comprising: a first layer, at the air side, of silicon dioxide; a second layer having an index of refraction of n 2 ; a third layer, adjacent the substrate, of ceric oxide, having an index of refraction of n 3 , and the second layer and the third layer satisfying the following conditions, respectively: 1.50≦n 2 ≦1.62, 0.04λ 0 ≦n 2 d 2 ≦0.15λ 0 , 1.92≦n 3 ≦2.10, 0.02λ 0 ≦n 3 d 3 ≦0.50λ 0 , wherein n 2 d 2 and n 3 d 3 are the optical thickness of the second layer and the third layer, respectively, and λ 0 is the dominant design wavelength.
Claim 3
Dependent Claim
75 words
An anti-reflection coating of claim 1, which further satisfies the below conditions: 1.45≦n 1 ≦1.47, 1.92≦n 3 ≦2.10, 0.20λο≦n 1 d 1 ≦0.32λο, 0.02λο≦n 3 d 3 ≦0.50λο, wherein n 1 : refractive index of the first layer, n 3 : refractive index of the third layer, n 1 d 1 : optical thickness of the first layer, n 3 d 3 : optical thickness of the third layer, λ 0 : design dominant wavelength.
Claim 4
Dependent Claim
127 words
An anti-reflection coating of four layers for a synthetic resin substrate, comprising: a first layer, at the air side, of silicon dioxide; a second layer comprising a material selected from the group consisting of zirconium oxide, titanium dioxide, hafnium dioxide, ceric oxide, tantalum oxide, and a mixture of zirconium oxide and titanium oxide; a third layer selected from one of aluminum oxide and silicon dioxide, and a fourth layer, on the surface of the synthetic resin substrate, comprising ceric oxide having an index of refraction of n 4 , and the fourth layer satisfying the following equations: 1.92≦n 4 ≦2.10, 0<n 4 d 4 ≦0.25λ 0 wherein n 4 d 4 is an optical thickness of the fourth layer and λ 0 is a dominant design wavelength.
Claim 5
Dependent Claim
127 words
An anti-reflection coating of four layers for a synthetic resin substrate, comprising: a first layer, at the air side, of silicon dioxide; a second layer comprising a material selected from the group consisting of zirconium oxide, titanium dioxide, hafnium dioxide, ceric oxide, tantalum oxide, and a mixture of zirconium oxide and titanium oxide; a third layer selected from one of aluminum oxide and silicon dioxide, and a fourth layer, on the surface of the synthetic resin substrate, comprising ceric oxide having an index of refraction of n 4 , and the fourth layer satisfying the following equations: 1.92≦n 4 ≦2.10, 0<n 4 d 4 ≦0.25λ 0 wherein n 4 d 4 is an optical thickness of the fourth layer and λ 0 is a dominant design wavelength.
Claim 6
Dependent Claim
131 words
An anti-reflection coating of claim 3, which further satisfies the below conditions: 1.45≦n 1 ≦1.47, 1.92≦n 2 ≦2.10, 1.45≦n 3 ≦1.62, 1.92≦n 4 ≦2.10, 0.25λο≦n 1 d 1 ≦0.30λο, 0.25λο≦n 2 d 2 ≦0.60λο, 0<n 3 d 3 ≦0.25λο, 0<n 4 d 4 ≦0.25λο, wherein n 1 : refractive index of the first layer, n 2 : refractive index of the second layer, n 3 : refractive index of the third layer, n 4 : refractive index of the fourth layer, n 1 d 1 : optical thickness of the first layer, n 2 d 2 : optical thickness of the second layer, n 3 d 3 : optical thickness of the third layer, n 4 d 4 : optical thickness of the fourth layer, λ 0 : design dominant wavelength.
Claim 7
Dependent Claim
105 words
An anti-reflection coating of five layers for a synthetic resin substrate, comprising: a first layer, at the air side, of silicon dioxide; a second layer of aluminum oxide; a third layer of ceric oxide; a fourth layer of aluminum oxide, and a fifth layer, on the surface of the synthetic resin substrate, of ceric oxide having an index of refraction of n 5 , and the fifth layer satisfying the following equations: 1.92≦n 5 ≦2.10, 0.05λ 0 ≦n 5 d 5 ≦0.20λ 0 , wherein n 5 d 5 is an optical thickness of the fifth layer and λ 0 is a dominant design wavelength.
Claim 8
Dependent Claim
105 words
An anti-reflection coating of five layers for a synthetic resin substrate, comprising: a first layer, at the air side, of silicon dioxide; a second layer of aluminum oxide; a third layer of ceric oxide; a fourth layer of aluminum oxide, and a fifth layer, on the surface of the synthetic resin substrate, of ceric oxide having an index of refraction of n 5 , and the fifth layer satisfying the following equations: 1.92≦n 5 ≦2.10, 0.05λ 0 ≦n 5 d 5 ≦0.20λ 0 , wherein n 5 d 5 is an optical thickness of the fifth layer and λ 0 is a dominant design wavelength.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1993-04-30 | 1993-10-30 | 1994-05-01 | $2000.00 | Window Closed / Lapsed |
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