US4641926A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polarizing element
Assignee: Fujitsu Ltd
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Filing: 1985-12-26
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Granted: 1987-02-10
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Expires: 2005-12-26
Abstract
Abstract A polarizing element comprising a transparent flat plate having at least two parallel surfaces, a polarizing separate layer provided on a portion of one parallel surface of the transparent flat plate and an optical reflecting material provided on a portion of the other parallel surface of the transparent flat plate.
Inventors
- 👤 Masataka Shirasaki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 21:57
CPC Classifications
G; G02; G02B; G02B5/00; G02B5/30; G02B27/00; G02B27/28; G02B27/283
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
185 words
A polarizing element comprising a first right angle prism, a second right angle prism, and a transparent flat plate having at least two parallel surfaces, a polarization separating layer provided on a portion of a first one of said two parallel surfaces of the transparent flat plate, and an optical reflecting layer provided on a portion of the second parallel surface of the transparent flat plate, said transparent flat plate being interposed between the first right angle prism and the second right angle prism, wherein each of said first and second right angle prisms has two right-angle-forming surfaces which intersect to form the respective right angle and a diagonal surface, wherein a light beam incident on a respective one of said surfaces of each of said first and second right angle prisms is separated into two respectively polarized light beams by said polarization separating layer, one of said polarized light beams is reflected by said optical reflecting layer, and two respective output light beams are output through a predetermined other one of said surfaces of a predetermined one of said first and second right-angle prisms.
Claim 2
Dependent Claim
185 words
A polarizing element comprising a first right angle prism, a second right angle prism, and a transparent flat plate having at least two parallel surfaces, a polarization separating layer provided on a portion of a first one of said two parallel surfaces of the transparent flat plate, and an optical reflecting layer provided on a portion of the second parallel surface of the transparent flat plate, said transparent flat plate being interposed between the first right angle prism and the second right angle prism, wherein each of said first and second right angle prisms has two right-angle-forming surfaces which intersect to form the respective right angle and a diagonal surface, wherein a light beam incident on a respective one of said surfaces of each of said first and second right angle prisms is separated into two respectively polarized light beams by said polarization separating layer, one of said polarized light beams is reflected by said optical reflecting layer, and two respective output light beams are output through a predetermined other one of said surfaces of a predetermined one of said first and second right-angle prisms.
Claim 3
Dependent Claim
46 words
The polarizing element of claim 1, wherein said incident light beam and said two respective output light beams are substantially perpendicular to the respective surface of each respective one of said right angle prisms upon which it is incident and from which it is output, respectively.
Claim 4
Dependent Claim
117 words
An optical switch, comprising: two of said polarizing elements of claim 2, arranged so that two light beams corresponding to said two respective output light beams output from said predetermined surface of said predetermined right angle prism of a first one of said polarizing elements are provided as respective input light beams to a predetermined respective surface of a predetermined one of said right angle prisms of the second polarizing element, and a Faraday rotator located between said two polarizing elements to receive as an input said two respective output beams output from said first polarizing element and to output said two light beams corresponding thereto as said respective input light beams to said second polarizing element.
Claim 5
Dependent Claim
56 words
The optical switch of claim 3, comprising a wave plate combined in series with said Faraday rotator, the combination thereof receiving as inputs said two output light beams from said first polarizing element, and providing as outputs from the combination said two corresponding light beams as said respective input light beams to said second polarizing element.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-02-09 | 1990-08-11 | 1991-02-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-02-09 | 1994-08-11 | 1995-02-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-02-09 | 1998-08-11 | 1999-02-10 | $7700.00 | Window Closed / Lapsed |