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US4673285A Expired / Lapsed US ⏱️ 0.0 years remaining

Optical scanning of duplex documents

Assignee: Xerox Corp
•
Filing: 1986-05-23
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Granted: 1987-06-16
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Expires: 2006-05-23
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Abstract

Abstract A scanning system is provided for sequentially scanning both sides of a duplex document and projecting images onto a light sensitive linear array. In a first configuration, the platen and scan/illumination stations are fixed and the document is moved across the platen in a scan and reverse scan direction. The scan/illumination stations are sequentially energized and images of both sides of the document are directed along separate optical paths until they are redirected by a movable mirror assembly into a common lens. In a second configuration, both sides of a duplex document are sequentially scanned by movable scan/illumination stations and directed into a common lens which sequentially projects the document images onto the linear array.

Inventors

  • 👤 David K. Shogren

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-07 23:52
CPC Classifications
G; G03; G03B; G03B27/00; G03B27/32; G03B27/52; H; H04; H04N; H04N1/00; H04N1/04; H04N1/12; H04N1/121; H04N1/0464; H04N1/19; H04N1/191; H04N1/192; H04N1/193

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 212 words
Apparatus for sequentially scanning both sides of a duplex document and for projecting line images along an optical path onto a light sensitive image member comprising, in combination: a stationary transparent platen located in an object plane, a first and second scan/illumination station positioned on opposite sides of said platen, means for moving a duplex document across said platen in a first direction to provide a scan excursion adjacent the first side of the document and in a reverse scan direction to provide a scan excursion adjacent the second side of the document, means for energizing said first scan/illumination station at the start of said first scan excursion whereby reflected first side images are propagated along a first optical path, means for energizing said second scan/illumination station at the start of said reverse scan excursion whereby reflected second side images are propagated along a second optical path, a stationary projection lens for projecting and focusing document images on the surface of said light sensitive member, and optical means positioned between the platen and said lens, said optical means adapted to sequentially direct said first and second side images along a common optical path into said lens, whereby said lens projects said images along a common optical path to said light sensitive member.
Claim 2
Dependent Claim 212 words
Apparatus for sequentially scanning both sides of a duplex document and for projecting line images along an optical path onto a light sensitive image member comprising, in combination: a stationary transparent platen located in an object plane, a first and second scan/illumination station positioned on opposite sides of said platen, means for moving a duplex document across said platen in a first direction to provide a scan excursion adjacent the first side of the document and in a reverse scan direction to provide a scan excursion adjacent the second side of the document, means for energizing said first scan/illumination station at the start of said first scan excursion whereby reflected first side images are propagated along a first optical path, means for energizing said second scan/illumination station at the start of said reverse scan excursion whereby reflected second side images are propagated along a second optical path, a stationary projection lens for projecting and focusing document images on the surface of said light sensitive member, and optical means positioned between the platen and said lens, said optical means adapted to sequentially direct said first and second side images along a common optical path into said lens, whereby said lens projects said images along a common optical path to said light sensitive member.
Claim 3
Dependent Claim 13 words
Apparatus according to claim 1 wherein said optical means includes a pivotable miror.
Claim 4
Dependent Claim 36 words
Apparatus according to claim 1 wherein said optical means includes a mirror pair adapted to be translated along the optical path, one of said mirrors being further adapted to selectively move out of the optical path.
Claim 5
Dependent Claim 16 words
Apparatus according to claim 1 wherein said light sensitive image memger is a linear image array.
Claim 6
Dependent Claim 178 words
Apparatus for sequentially scanning both sides of a duplex document and for projecting line images along an optical path onto a light sensitive image member comprising, in combination: a stationary transparent platen located in an object plane, a first and second scan/illumination station positioned on opposite sides of said platen, means for moving a duplex document across said platen in a first direction to provide a scan excursion adjacent the first side of the document and in a reverse scan direction to provide a scan excursion adjacent the second side of the document, means for energizing said first scan/illumination station at the start of said first scan excursion whereby reflected first side images are propagated along a first optical path, means for energizing said second scan/illumination station at the start of said reverse scan excursion whereby reflected second side images are propagated along a second optical path, a projection lens sequentially movable from said first to said second optical path for projecting and focusing first and second side document images onto the surface of said light sensitive member.
Claim 7
Dependent Claim 178 words
Apparatus for sequentially scanning both sides of a duplex document and for projecting line images along an optical path onto a light sensitive image member comprising, in combination: a stationary transparent platen located in an object plane, a first and second scan/illumination station positioned on opposite sides of said platen, means for moving a duplex document across said platen in a first direction to provide a scan excursion adjacent the first side of the document and in a reverse scan direction to provide a scan excursion adjacent the second side of the document, means for energizing said first scan/illumination station at the start of said first scan excursion whereby reflected first side images are propagated along a first optical path, means for energizing said second scan/illumination station at the start of said reverse scan excursion whereby reflected second side images are propagated along a second optical path, a projection lens sequentially movable from said first to said second optical path for projecting and focusing first and second side document images onto the surface of said light sensitive member.
Claim 8
Dependent Claim 221 words
Apparatus for sequentially scanning both sides of a duplex document and for projecting line images along an optical path onto a light sensitive image member comprising, in combination: a stationary transparent platen located in an object plane, a first and second scan/illumination station positioned on opposite sides of said platen, means for moving said first scan/illumination station across said platen in a first direction to provide a scan excursion adjacent the first side of the document, said moving means being further adapted to move said second scan/illumination station in a reverse scan direction to provide a scan excursion adjacent the second side of the document, means for energizing said first scan/illumination station at the start of said first scan excursion whereby reflected first side images are propagated along a first optical path, means for energizing said second scan/illumination station at the start of said reverse scan excursion whereby refected second side images are propagated along a second optical path, a projection lens for projecting and focusing document images on the surface of said light sensitive member, and optical means positioned between the platen and said lens, said optical means adapted to sequentially direct said first and second side images along a common optical path into said lens, whereby said lens projects said images along a common optical path to said member.
Claim 9
Dependent Claim 221 words
Apparatus for sequentially scanning both sides of a duplex document and for projecting line images along an optical path onto a light sensitive image member comprising, in combination: a stationary transparent platen located in an object plane, a first and second scan/illumination station positioned on opposite sides of said platen, means for moving said first scan/illumination station across said platen in a first direction to provide a scan excursion adjacent the first side of the document, said moving means being further adapted to move said second scan/illumination station in a reverse scan direction to provide a scan excursion adjacent the second side of the document, means for energizing said first scan/illumination station at the start of said first scan excursion whereby reflected first side images are propagated along a first optical path, means for energizing said second scan/illumination station at the start of said reverse scan excursion whereby refected second side images are propagated along a second optical path, a projection lens for projecting and focusing document images on the surface of said light sensitive member, and optical means positioned between the platen and said lens, said optical means adapted to sequentially direct said first and second side images along a common optical path into said lens, whereby said lens projects said images along a common optical path to said member.
Claim 10
Dependent Claim 21 words
Apparatus according to claim 6 wherein said optical means includes a sequentially activated first and second full rate/half rate mirror assembly.
Claim 11
Dependent Claim 22 words
Apparatus according to claim 7 wherein said lens is movable along the optical path to maintain total conjugate during each scan excursion.
Claim 12
Dependent Claim 18 words
Apparatus according to claim 7 wherein said lens is sequentially converted from a straight-through lens to a half-lens.
Claim 13
Dependent Claim 43 words
Apparatus according to claim 6 wherein both first and second side images are reflected from at least one common mirror surface into the lens and wherein said lens is adapted to move in a scanning direction during said first and second scan excursion.

References Cited (Backward Citations)

US2578320A Cited
US3318212A Cited
US3885871A Cited
US3998543A Cited
US4035073A Cited
US4536077A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-06-15 1990-12-15 1991-06-16 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-06-15 1994-12-15 1995-06-16 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-06-15 1998-12-15 1999-06-16 $7700.00 Window Closed / Lapsed

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