US3912920A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polarized light illumination device
Assignee: Individual
•
Filing: 1974-02-06
•
Granted: 1975-10-14
•
Expires: 1994-02-06
Abstract
Abstract Light from a light source in the headlight of vehicles is polarized by forming a parallel beam with a paraboloidal reflector behind the light source and disposing a transparent laminated plate in the path of the beam. The plate is composed of transparent sheets disposed at an angle equal to the polarization angle and a material (e.g. air) between the sheets with a refractive index different from the refractive index of the sheets. The interfaces of the sheets and material polarize the parallel light and the light is projected to the next transparent sheet. The edge surfaces of the sheets are angular relative to the planes of the sheets and form light penetration planes and emergence planes both extending along the length of the plate. The planes are substantially perpendicular to the optical axis of the parallel light.
Inventors
- 👤 Josuke Kubota
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 22:19
CPC Classifications
G; G02; G02B; G02B27/00; G02B27/28; G02B27/283; G02B27/285; F; F21; F21S; F21S41/00; F21S41/10; F21S41/12; F21S41/135
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
207 words
A polarizing device for polarizing light from a light source in the headlight of vehicles, comprising a. a paraboloidal reflector behind the light source for forming a parallel beam with light from the light source; b. a transparent laminated plate disposed in the path of the beam of parallel light, said plate comprising a plurality of transparent sheets having a material between the sheets, said material having a refractive index different from the refractive index of said sheets, each of said sheets being angularly disposed relative to the optical axis of the parallel light from the beam at an angle equal to the polarization angle so that the parallel light is refracted at the interface of the transparent sheets and the material and projected to the next transparent sheet at the polarization angle, said sheets each having surfaces at their edges, said surfaces being angular relative to the planes of the sheets, said surfaces forming a light penetration plane extending along a substantial majority of one side of said plate and an emergence plane extending along a substantial majority of the other side of said plate for the parallel light projected on said plate, said planes being substantially perpendicular to the optical axis of the parallel light.
Claim 2
Dependent Claim
207 words
A polarizing device for polarizing light from a light source in the headlight of vehicles, comprising a. a paraboloidal reflector behind the light source for forming a parallel beam with light from the light source; b. a transparent laminated plate disposed in the path of the beam of parallel light, said plate comprising a plurality of transparent sheets having a material between the sheets, said material having a refractive index different from the refractive index of said sheets, each of said sheets being angularly disposed relative to the optical axis of the parallel light from the beam at an angle equal to the polarization angle so that the parallel light is refracted at the interface of the transparent sheets and the material and projected to the next transparent sheet at the polarization angle, said sheets each having surfaces at their edges, said surfaces being angular relative to the planes of the sheets, said surfaces forming a light penetration plane extending along a substantial majority of one side of said plate and an emergence plane extending along a substantial majority of the other side of said plate for the parallel light projected on said plate, said planes being substantially perpendicular to the optical axis of the parallel light.
Claim 3
Dependent Claim
76 words
A polarized illumination device according to claim 1, wherein said laminated plate has at each outer side thereof an outwardly supporting transparent plate which is joined to aligned end portions of said transparent sheets uniformly forming said laminated plate, said supporting transparent plate having an angle of pi /2 minus the polarization angle with respect to said transparent sheets, said outwardly supporting transparent plate being illuminated perpendicularly thereto by the parallel beam from the light source.
Claim 4
Dependent Claim
106 words
A polarized light illumination device according to claim 1; wherein said uniform transparent sheets each has an end surface thereof formed at right angles to the elongate direction thereof, a transparent plate joined to the aligned end portions of said transparent sheets at both outer sides of said laminated plate in the relation that said transparent plate has respectively an angle of pi /2 minus the polarization angle with respect to said transparent sheets, and a material filled into the space between said transparent plate and the aligned end portions of said transparent sheets, said material having a refractive index equal to said uniform transparent sheets.
Claim 5
Dependent Claim
11 words
A device as in claim 1, wherein the material is air.
Claim 6
Dependent Claim
15 words
A device as in claim 1, wherein said sheets are composed of an isotropic material.
References Cited (Backward Citations)
US2270535A
Cited
US2748659A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-10-13 | 1979-04-14 | 1979-10-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-10-13 | 1983-04-14 | 1983-10-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-10-13 | 1987-04-14 | 1987-10-14 | $7700.00 | Window Closed / Lapsed |