EP0186166A1
Expired / Lapsed
EP
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Optical low pass filter utilizing a phase grating
Assignee: Sony Corp
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Filing: 1985-12-20
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Granted: —
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Expires: 2005-12-20
Abstract
Abstract 57 An optical low pass filter including a phase grating (1), wherein the grating is implanted inwardly from the surface of a substrate (2), the grating having a uniform repetitive period and having a refractive index different from that of the substrate.
Inventors
- 👤 Kouichi Ise
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-28 09:04
CPC Classifications
G; G02; G02F; G02F2/00; G02B; G02B6/00; G02B6/10; G02B6/12; G02B6/122; G02B6/124; G02B27/00; G02B27/42; G02B27/46; G02B5/00; G02B5/18; G02B5/1866; G02B5/1871
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
43 words
An optical low pass filter including: a substrate (2), a phase grating (1) implanted within said substrate (2) and having a surface flush therewith, said grating (1) having a uniform repetitive period and having a refractive index different from that of said substrate.
Claim 2
Dependent Claim
43 words
An optical low pass filter including: a substrate (2), a phase grating (1) implanted within said substrate (2) and having a surface flush therewith, said grating (1) having a uniform repetitive period and having a refractive index different from that of said substrate.
Claim 3
Dependent Claim
16 words
An optical filter according to claim 1 wherein said grating consists of a stripe-like pattern (3).
Claim 4
Dependent Claim
38 words
An optical filter according to claim 1 which includes a pair of gratings formed in surfaces of said substrate which are perpendicular to each other, each of said pair of gratings having a period different from each other.
Claim 5
Dependent Claim
36 words
An optical filter according to claim 1 which includes a pair of gratings (14) in one surface extending in rows and columns on one surface (13) of said substrate (2) which are perpendicular to each other.
Claim 6
Dependent Claim
34 words
An optical filter according to claim 1 wherein the refractive index N of said grating and the refractive index N of said substrate along the x, y and z axes have the following relationship:
Claim 9
Dependent Claim
21 words
An optical filter according to claim 1 wherein the difference in optical distance between the grating and the substrate rises smoothly.
Claim 10
Dependent Claim
32 words
An optical filter according to claim 6 wherein the shape of the grating is such as to cause the difference in optical distance between the grating and the substrate to rise smoothly.
Claim 11
Dependent Claim
31 words
An optical filter according to claim 6 wherein the variation of refractive index within said grating causes the difference in optical distance between the grating and the substrate to rise smoothly.
References Cited (Backward Citations)
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