US3946150A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical scanner
Assignee: Xerox Corp
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Filing: 1973-12-20
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Granted: 1976-03-23
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Expires: 1993-12-20
Abstract
Abstract A flux scanner which is comprised of a rotating polygon for scanning a beam of radiated flux transverse a photoreceptive medium. In the beam path between the flux source and the polygon, an astigmatic-beam expander lens is employed to focus the flux distributions to a spot at an image plane. The astigmatic lens is configured so as to produce a very narrow beam of flux to control the size of the spot in a direction orthogonal to the transverse direction, without any loss of efficiency. Between the photoreceptive medium and the polygon, a cylindrical lens and linear optical elements are positioned to focus the beam to control the size of the spot along the transverse direction. The transverse direction is designated optically as the tangential plane; whereas the direction orthogonal to the transverse direction is designated optically as the sagittal plane. These optical elements are configured to cause the sagittal and tangential planes of best focus to coincide at the image plane even though the object effectively emanates from two separate locations.
Inventors
- 👤 David Grafton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 17:35
CPC Classifications
G; G02; G02B; G02B27/00; G02B27/0025; G02B27/0031; G02B13/00; G02B13/0005; G02B26/00; G02B26/08; G02B26/10; G02B26/12; G02B26/125; G03; G03B; G03B27/00; G03B27/32; G03B27/52; G03B27/522; G03B27/525; G03B27/526; G03B41/00; G03B41/02; G03B41/04; G03B41/06; H; H04; H04N; H04N1/00; H04N1/024; H04N1/032; H04N1/036; H04N1/04; H04N1/113; H04N1/1135
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
202 words
Apparatus for recording information onto a scanned medium comprising: laser means for generating a collimated beam of radiation, means for modulating the beam in accordance with the information content of an electrical signal, first optical means for imaging said modulated beam to a spot in a focal plane at the surface of said medium, said medium being sensitive to said radiation beam, scanning means positioned between said laser means and said medium for scanning the spot across said medium to impart the information content of said spot to said medium, second optical means positioned between said laser means and said scanning means for focusing said beam to a predetermined spot size, said second optical means comprising first and second cylindrical lens elements, said first cylindrical lens element being positioned with its power plane substantially orthogonal to the scan direction and said second cylindrical lens element being positioned with its power plane substantially parallel to the scan direction, and a cylindrical lens positioned in the optical path of the imaged beam between said first optical means and said medium with its power plane substantially orthogonal to the direction of scan whereby said beam is focused to maintain the spot in said focal plane.
Claim 2
Dependent Claim
202 words
Apparatus for recording information onto a scanned medium comprising: laser means for generating a collimated beam of radiation, means for modulating the beam in accordance with the information content of an electrical signal, first optical means for imaging said modulated beam to a spot in a focal plane at the surface of said medium, said medium being sensitive to said radiation beam, scanning means positioned between said laser means and said medium for scanning the spot across said medium to impart the information content of said spot to said medium, second optical means positioned between said laser means and said scanning means for focusing said beam to a predetermined spot size, said second optical means comprising first and second cylindrical lens elements, said first cylindrical lens element being positioned with its power plane substantially orthogonal to the scan direction and said second cylindrical lens element being positioned with its power plane substantially parallel to the scan direction, and a cylindrical lens positioned in the optical path of the imaged beam between said first optical means and said medium with its power plane substantially orthogonal to the direction of scan whereby said beam is focused to maintain the spot in said focal plane.
Claim 3
Dependent Claim
38 words
The apparatus as defined in claim 1 wherein said second optical means further includes a third cylindrical lens element interposed between said first and second cylindrical lens elements with its power plane substantially orthogonal to the scan direction.
Claim 4
Dependent Claim
25 words
The apparatus as defined in claim 2 wherein said first and second cylindrical lens element are plano-convex and said third cylindrical lens element is plano-concave.
Claim 5
Dependent Claim
47 words
The apparatus as defined in claim 1 wherein said scanning means includes a multifaceted polygon having reflective facets for reflecting the modulated beam incident to it onto said medium and means for rotating said polygon such that the spot is scanned in successive traces across said medium.
Claim 6
Dependent Claim
41 words
The apparatus as defined in claim 4 wherein said first optical means comprises a plurality of lens elements selected such that a linear relationship between the angular position of the rotating polygon and the position of the scanning spot is provided.
Claim 7
Dependent Claim
30 words
The apparatus as defined in claim 5 wherein said plurality of lens elements comprise a first positive lens element, a second negative lens element and a third positive lens element.
Claim 8
Dependent Claim
194 words
Apparatus for recording information onto a scanned medium comprising: laser means for generating a collimated beam of radiation, means for modulating the beam in accordance with the information content of an electrical signal, first optical means for imaging said modulated beam to a spot in a focal plane at the surface of said medium, said medium being sensitive to said radiation beam, said first optical means comprising a plurality of lens elements selected such that a linear relationship between the angular position of the rotating polygon and the position of the scanning spot is provided. a rotating multifaceted polygon positioned between said laser means and said medium for scanning the spot across said medium in successive traces to impart the information content of said spot to said medium, second optical means positioned between said laser means and said scanning means for focusing said beam to a predetermined spot size, and a cylindrical lens positioned in the optical path of the imaged beam between said first optical means and said medium with its power plane substantially orthogonal to the direction of scan whereby said beam is focused to maintain the spot in said focal plane.
Claim 9
Dependent Claim
194 words
Apparatus for recording information onto a scanned medium comprising: laser means for generating a collimated beam of radiation, means for modulating the beam in accordance with the information content of an electrical signal, first optical means for imaging said modulated beam to a spot in a focal plane at the surface of said medium, said medium being sensitive to said radiation beam, said first optical means comprising a plurality of lens elements selected such that a linear relationship between the angular position of the rotating polygon and the position of the scanning spot is provided. a rotating multifaceted polygon positioned between said laser means and said medium for scanning the spot across said medium in successive traces to impart the information content of said spot to said medium, second optical means positioned between said laser means and said scanning means for focusing said beam to a predetermined spot size, and a cylindrical lens positioned in the optical path of the imaged beam between said first optical means and said medium with its power plane substantially orthogonal to the direction of scan whereby said beam is focused to maintain the spot in said focal plane.
Claim 10
Dependent Claim
30 words
The apparatus as defined in claim 7 wherein said plurality of lens elements comprise a first positive lens element, a second negative lens element and a third positive lens element.
Claim 11
Dependent Claim
54 words
The apparatus as defined in claim 7 wherein said second optical means comprises: first and second cylindrical lens elements, said first cylindrical lens element being positioned with its power plane substantially orthogonal to the scan direction and said second cylindrical lens element being positioned with its power plane substantially parallel to the scan direction.
Claim 12
Dependent Claim
38 words
The apparatus as defined in claim 9 wherein said second optical means further includes a third cylindrical lens element interposed between said first and second cylindrical lens elements with its power plane substantially orthogonal to the scan direction.
Claim 13
Dependent Claim
25 words
The apparatus as defined in claim 10 wherein said first and second cylindrical lens elements are plano-convex and said third cylindrical lens element is plano-concave.
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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) | 1979-03-23 | 1979-09-22 | 1980-03-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-03-23 | 1983-09-22 | 1984-03-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-03-23 | 1987-09-22 | 1988-03-23 | $7700.00 | Window Closed / Lapsed |