Patent US4929844A successfully refreshed from Google Patents.
US4929844A
Expired / Lapsed
US
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Apparatus for detecting the presence and size of a document
Assignee: Sanyo Electric Co Ltd
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Filing: 1988-11-18
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Granted: 1990-05-29
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Expires: 2008-11-18
Abstract
Abstract The invention relates to a reading apparatus provided with a document table. More particularly, it relates to a reading apparatus which automatically detects the presence or absence of a document and/or the size of a document mounted on the document table. The reading apparatus related to the invention is provided with a light source which illuminates the document table and a means for collecting information about light intensity of the document table. The reading apparatus first gains information about light intensity of the document table when the light source is off and that when it is on, and then by comparing these informations, it detects the presence or absence of a document and/or the size of the document. Accordingly, the reading apparatus correctly detects the presence or absence of a document and/or the size of the document without being affected by external light even when the document cover remains open. Furthermore, the reading apparatus correctly detects the presence or absence of a document and/or the size of the document without taking the open and closed condition of the document cover into account.
Inventors
- 👤 Yuji Houjiyou
- 👤 Hiroyuki Hayasaki
- 👤 Kyoichi Yonezawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-10 02:21
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/00681; H04N1/00684; H04N1/00687; H04N1/00708; H04N1/00742; H04N1/00748; H04N1/0075; H04N1/00753; H04N1/00763; H04N1/00769; H04N2201/00; H04N2201/04; H04N2201/0402; H04N2201/0422
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
87 words
A reading apparatus which automatically detects the presence or absence of a document on a document table, comprising; a light source which illuminates said document table; a collecting means which collects information about light intensity of said document table; a comparing means which compares said information when said light source is off with that when said light source is on; and means for determining the presence or absence of a document on said document table in accordance with the result of comparison executed by said comparing means.
Claim 2
Dependent Claim
87 words
A reading apparatus which automatically detects the presence or absence of a document on a document table, comprising; a light source which illuminates said document table; a collecting means which collects information about light intensity of said document table; a comparing means which compares said information when said light source is off with that when said light source is on; and means for determining the presence or absence of a document on said document table in accordance with the result of comparison executed by said comparing means.
Claim 3
Dependent Claim
18 words
The reading apparatus as set forth in claim 1, wherein said collecting means is composed of image sensors.
Claim 4
Dependent Claim
28 words
The reading apparatus as set forth in claim 1, wherein said information about light intensity relates to a continuous length and density of base color of said document.
Claim 5
Dependent Claim
19 words
The reading apparatus as set forth in claim 1, wherein said document table is provided with a document cover.
Claim 6
Dependent Claim
27 words
The reading apparatus as set forth in claim 4, wherein said document cover is provided with a color mark which absorbs the light from said light source.
Claim 7
Dependent Claim
38 words
The reading apparatus as set forth in claim 5, wherein said collecting means collects information about light intensity of the part corresponding to the position at which said color mark is provided when said document cover is shut.
Claim 8
Dependent Claim
36 words
The reading apparatus as set forth in claim 1, wherein said light source is moved to allow said collecting means to read information of a document by the illumination from said light source onto said document.
Claim 9
Dependent Claim
79 words
A reading apparatus which automatically detects the size of a document on a document table, comprising; a light source which illuminates said document table; a collecting means which collects information about light intensity of said document table; a comparing means which compares said information when said light source is off with that when said light source is on; and means for determining the size of said document in accordance with the result of comparison executed by said comparing means.
Claim 10
Dependent Claim
79 words
A reading apparatus which automatically detects the size of a document on a document table, comprising; a light source which illuminates said document table; a collecting means which collects information about light intensity of said document table; a comparing means which compares said information when said light source is off with that when said light source is on; and means for determining the size of said document in accordance with the result of comparison executed by said comparing means.
Claim 11
Dependent Claim
18 words
The reading apparatus as set forth in claim 8, wherein said collecting means is composed of image sensors.
Claim 12
Dependent Claim
28 words
The reading apparatus as set forth in claim 8, wherein said information about light intensity relates to a continuous length and density of base color of said document.
Claim 13
Dependent Claim
19 words
The reading apparatus as set forth in claim 8, wherein said document table is provided with a document cover.
Claim 14
Dependent Claim
27 words
The reading apparatus as set forth in claim 11, wherein said document cover is provided with a color mark which absorbs the light from said light source.
Claim 15
Dependent Claim
38 words
The reading apparatus as set forth in claim 12, wherein said collecting means collects information about light intensity of the part corresponding to the position at which said color mark is provided when said document cover is shut.
Claim 16
Dependent Claim
32 words
The reading apparatus as set forth in claim 8, wherein said information about light intensity is collected from a plurality of predetermined sections in the direction of the width of said document.
Claim 17
Dependent Claim
36 words
The reading apparatus as set forth in claim 8, wherein said light source is moved to allow said collecting means to read information of a document by the illumination from said light source onto said document.
References Cited (Backward Citations)
US4458264A
Cited
US4734762A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-05-28 | 1993-11-27 | 1994-05-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-05-28 | 1997-11-27 | 1998-05-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-05-28 | 2001-11-27 | 2002-05-29 | $7700.00 | Window Closed / Lapsed |