Patent US5513035A successfully refreshed from Google Patents.
US5513035A
Expired / Lapsed
US
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Infrared polarizer
Assignee: Panasonic Holdings Corp
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Filing: 1994-08-24
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Granted: 1996-04-30
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Expires: 2014-08-24
Abstract
Abstract A polarizer comprising; a substrate transparent to a light of actual use and optical thin films of a higher refractive index than that of said substrate deposited on both surfaces of said substrate. The substrate is arranged so as to receive the incident light obliquely thereto. When the incident angle and the thickness of the optical thin film are optimally selected, the transmittance for the P polarized light can be made approximately 100%, while that for the S polarized light very small. The polarizer can extract a substantially linearly polarized light from natural light, A projection image display system has the polarizer as its pre-polarizer. The polarizer is also useful for infrared radiation.
Inventors
- 👤 Yoshito Miyatake
- 👤 Shinya Sannohe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 15:05
CPC Classifications
G; G02; G02B; G02B5/00; G02B5/30; H; H04; H04N; H04N9/00; H04N9/12; H04N9/31; H04N9/3141; H04N9/315; H04N9/3167; G02B27/00; G02B27/28; G02B27/283; G02B5/3025; G02B5/3033; H04N9/3102; H04N9/3105
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
82 words
A polarizer comprising: at least one polarization-selective mirror including a substrate made of a substance which is substantially transparent to infrared radiation, and optical thin films with a higher refractive index than that of said substrate disposed on opposite surfaces of said substrate, said at least one mirror being obliquely arranged with respect to a given optical axis such that a transmittance of the polarizer for P polarized light incident upon the polarizer along said optical axis is at a maximum value.
Claim 2
Dependent Claim
82 words
A polarizer comprising: at least one polarization-selective mirror including a substrate made of a substance which is substantially transparent to infrared radiation, and optical thin films with a higher refractive index than that of said substrate disposed on opposite surfaces of said substrate, said at least one mirror being obliquely arranged with respect to a given optical axis such that a transmittance of the polarizer for P polarized light incident upon the polarizer along said optical axis is at a maximum value.
Claim 3
Dependent Claim
23 words
The polarizer in accordance with claim 1, wherein said substrate is made from silicon and said optical thin films are made from germanium.
Claim 4
Dependent Claim
30 words
The polarizer in accordance with claim 1, wherein said substrate is made from a substance selected from the group consisting of sodium chloride, potassium chloride, calcium difluoride and barium difluoride.
Claim 5
Dependent Claim
26 words
The polarizer in accordance with claim 1 wherein said optical thin films are made from a substance selected from the group consisting of silicon and germanium.
Claim 6
Dependent Claim
31 words
The polarizer in accordance with claim 1, wherein a plurality of said polarization-selective mirrors are provided, and further comprising a framework for supporting said plurality of polarization-selective mirrors in zig-zag fashion.
Claim 7
Dependent Claim
17 words
The polarizer in accordance with claim 5, wherein an even number of said polarization-selective mirrors are provided.
Claim 8
Dependent Claim
46 words
The polarizer in accordance with claim 1, wherein a plurality of polarization-selective mirrors are provided, and wherein at least two of said polarization-selective mirrors are disposed in spaced parallel relation with one another so as to sandwich a thin air layer or a thin gap therebetween.
Claim 9
Dependent Claim
83 words
The polarizer in accordance with claim 7, wherein a plurality of said polarization-selective mirrors are provided, and further comprising a framework which supports said polarization-selective mirrors in such a fashion as to form at least two mirror units each forming a zig-zag pattern, said mirror units being concentrically arranged so as to sandwich a zig-zag shaped gap therebetween such that a transmittance of the polarizer for P polarized infrared radiation incident upon the polarizer along said optical axis is at a maximum value.
Claim 10
Dependent Claim
19 words
The polarizer in accordance with claim 8, wherein an even number of mirror units are supported by said framework.
Claim 11
Dependent Claim
189 words
A polarizer comprising: at least one polarization-selective mirror including a substrate made of a substance which is substantially transparent to infrared radiation, and optical thin films with a higher refractive index than that of said substrate disposed on opposite surfaces of said substrate, said at least one mirror being obliquely arranged with respect to a given optical axis such that a transmittance of the polarizer for P polarized light incident upon the polarizer along said optical axis is at a maximum value, said polarizer satisfying the following conditions: ##EQU7## where n 0 represents a refractive index of an exterior medium; n 1 represents a refractive index of the optical thin films; n 2 represents a refractive index of the substrate; d represents a thickness of the optical thin films; θ 0 represents an incident angle at which the light enters from the exterior medium into the optical thin film, θ 1 represents an angle of refraction of infrared radiation in said optical thin film; θ 2 represents an angle of refraction of infrared radiation in said substrate; and λ represents a main wavelength of infrared radiation traveling through air.
Claim 12
Dependent Claim
189 words
A polarizer comprising: at least one polarization-selective mirror including a substrate made of a substance which is substantially transparent to infrared radiation, and optical thin films with a higher refractive index than that of said substrate disposed on opposite surfaces of said substrate, said at least one mirror being obliquely arranged with respect to a given optical axis such that a transmittance of the polarizer for P polarized light incident upon the polarizer along said optical axis is at a maximum value, said polarizer satisfying the following conditions: ##EQU7## where n 0 represents a refractive index of an exterior medium; n 1 represents a refractive index of the optical thin films; n 2 represents a refractive index of the substrate; d represents a thickness of the optical thin films; θ 0 represents an incident angle at which the light enters from the exterior medium into the optical thin film, θ 1 represents an angle of refraction of infrared radiation in said optical thin film; θ 2 represents an angle of refraction of infrared radiation in said substrate; and λ represents a main wavelength of infrared radiation traveling through air.
Claim 13
Dependent Claim
23 words
The polarizer in accordance with claim 10, wherein said substrate is made from silicon and said optical thin films are made from germanium.
Claim 14
Dependent Claim
30 words
The polarizer in accordance with claim 10, wherein said substrate is made from a substance selected from the group consisting of sodium chloride, potassium chloride, calcium difluoride and barium difluoride.
Claim 15
Dependent Claim
26 words
The polarizer in accordance with claim 10, wherein said optical thin films are made from a substance selected from the group consisting of silicon and germanium.
Claim 16
Dependent Claim
31 words
The polarizer in accordance with claim 10, wherein a plurality of said polarization-selective mirrors are provided, and further comprising a framework for supporting said plurality of polarization-selective mirrors in zig-zag fashion.
Claim 17
Dependent Claim
17 words
The polarizer in accordance with claim 10, wherein an even number of said polarization-selective mirrors are provided.
Claim 18
Dependent Claim
46 words
The polarizer in accordance with claim 10, wherein a plurality of polarization-selective mirrors are provided, and wherein at least two of said polarization-selective mirrors are disposed in spaced parallel relation with one another so as to sandwich a thin air layer or a thin gap therebetween.
Claim 19
Dependent Claim
82 words
The polarizer in accordance with claim 10, wherein a plurality of said polarization-selective mirrors are provided, and further comprising a framework which supports said polarization-selective mirrors in such fashion as to form at least two mirror units each forming a zig-zag pattern, said mirror units being concentrically arranged so as to sandwich a zig-zag shaped gap therebetween such that a transmittance of the polarizer for P polarized infrared radiation incident upon the polarizer along said optical axis is at a maximum value.
Claim 20
Dependent Claim
19 words
The polarizer in accordance with claim 10, wherein an even number of mirror units are supported by said framework.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1999-04-30 | 1999-10-30 | 2000-04-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-04-30 | 2003-10-30 | 2004-04-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-04-30 | 2007-10-30 | 2008-04-30 | $7700.00 | Window Closed / Lapsed |