Patent US317971A successfully refreshed from Google Patents.
Patent DE36174C successfully refreshed from Google Patents.
Patent US5146351A successfully refreshed from Google Patents.
US5146351A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Image reader
Assignee: Panasonic Holdings Corp
•
Filing: 1991-08-21
•
Granted: 1992-09-08
•
Expires: 2011-08-21
Abstract
Abstract An image signals of a black reference plate, a white reference plate and a manuscript detected by an image sensor are converted into digital data by an A/D converter, and in the A/D conversion, the image signal of the black reference plate which is enhanced in level is applied to the A/D converter, and then the enhanced digital data for the black reference plate is returned to an original level, and a corrected image data which is represented by a difference of the image data of the manuscript and the image data of the black reference plate is issued.
Inventors
- 👤 Yoshiaki Maehara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 16:25
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/40; H04N1/407; H04N1/4076; H04N1/401
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
213 words
An image reader for reading a manuscript arranged on a manuscript plane, comprising: a black reference object having a minimum reflection coefficient also arranged on said manuscript plane, an image sensor for issuing image signals of multi-gradation images of an object on said manuscript plane, an A/D converter for converting said image signals detected by said image sensor into digital data based on a reference voltage wherein a range of said converting depends on a value of said reference voltage, a voltage selector means for supplying said reference voltage to said A/D converter, supplying a first reference voltage for detecting said black reference object to said A/D converter, which is lower than a second reference voltage supplied for detecting said manuscript so that said black reference object is A/D converted with a higher dynamic range, a dividing means for dividing said digital data of the black reference object from said A/D converter to another digital data, a subtracter for subtracting the another digital data of said black reference object from the digital data of the manuscript to obtain a difference therebetween, and issuing digital data indicative of said difference, and a calculator for converting the digital data of said difference into digital data having a same number of bits as said A/D converter.
Claim 2
Dependent Claim
213 words
An image reader for reading a manuscript arranged on a manuscript plane, comprising: a black reference object having a minimum reflection coefficient also arranged on said manuscript plane, an image sensor for issuing image signals of multi-gradation images of an object on said manuscript plane, an A/D converter for converting said image signals detected by said image sensor into digital data based on a reference voltage wherein a range of said converting depends on a value of said reference voltage, a voltage selector means for supplying said reference voltage to said A/D converter, supplying a first reference voltage for detecting said black reference object to said A/D converter, which is lower than a second reference voltage supplied for detecting said manuscript so that said black reference object is A/D converted with a higher dynamic range, a dividing means for dividing said digital data of the black reference object from said A/D converter to another digital data, a subtracter for subtracting the another digital data of said black reference object from the digital data of the manuscript to obtain a difference therebetween, and issuing digital data indicative of said difference, and a calculator for converting the digital data of said difference into digital data having a same number of bits as said A/D converter.
Claim 3
Dependent Claim
221 words
An image reader for reading a manuscript arranged on a manuscript plane, comprising: a black reference object having a minimum reflection coefficient also arranged on said manuscript plane, an image sensor for issuing image signals of multi-gradation images of an object on said manuscript plane, an A/D converter for converting said image signal into digital data on the basis of a reference level wherein a range of said converting depends on a value of said reference voltage, voltage selector means for supplying a first reference level to said A/D converter for detecting said black reference object on said manuscript plane and supplying a second reference level to said A/D converter for detecting said manuscript on said manuscript plane, said first reference voltage being lower than said second reference voltage so that said black reference object is A/D converted with a higher dynamic range, a dividing means for dividing a value of said digital data of the black reference object to form divided digital data, a subtracter for subtracting the divided digital data of said black reference object from the digital data of the manuscript to obtain a difference therebetween, and issuing digital data indicative of said difference, and a calculator for converting the digital data of said difference into digital data of the same number of bits as said A/D converter.
Claim 4
Dependent Claim
221 words
An image reader for reading a manuscript arranged on a manuscript plane, comprising: a black reference object having a minimum reflection coefficient also arranged on said manuscript plane, an image sensor for issuing image signals of multi-gradation images of an object on said manuscript plane, an A/D converter for converting said image signal into digital data on the basis of a reference level wherein a range of said converting depends on a value of said reference voltage, voltage selector means for supplying a first reference level to said A/D converter for detecting said black reference object on said manuscript plane and supplying a second reference level to said A/D converter for detecting said manuscript on said manuscript plane, said first reference voltage being lower than said second reference voltage so that said black reference object is A/D converted with a higher dynamic range, a dividing means for dividing a value of said digital data of the black reference object to form divided digital data, a subtracter for subtracting the divided digital data of said black reference object from the digital data of the manuscript to obtain a difference therebetween, and issuing digital data indicative of said difference, and a calculator for converting the digital data of said difference into digital data of the same number of bits as said A/D converter.
Claim 5
Dependent Claim
226 words
An image reader for reading a manuscript arranged on a manuscript plane, comprising: a black reference object having a minimum reflection coefficient also arranged on said manuscript plane, an image sensor including a semiconductor charge coupled device for issuing image signals of multi-gradation images of said manuscript, and for issuing enhanced image signals of said black reference object by prolonging respective periodic times of a scanning starting signal and a scanning clock signal, an A/D converter for converting said image signal from said image sensor into digital data based on a reference voltage wherein a range of said converting depends on a value of said reference voltage, a voltage selector means for supplying a first reference voltage for detecting said black reference object being lower than a second reference voltage for detecting said manuscript to said A/D converter so that said black reference object is A/D converted with a higher dynamic range, a dividing means for dividing said digital data of the black reference object to a divided value, a subtracter for subtracting the divided digital data of said black reference object from the digital data of the manuscript to obtain a difference therebetween, and issuing digital data indicative of said difference, and a calculator for converting the digital data of the difference into digital data of the same number of bits as said A/D converter.
Claim 6
Dependent Claim
226 words
An image reader for reading a manuscript arranged on a manuscript plane, comprising: a black reference object having a minimum reflection coefficient also arranged on said manuscript plane, an image sensor including a semiconductor charge coupled device for issuing image signals of multi-gradation images of said manuscript, and for issuing enhanced image signals of said black reference object by prolonging respective periodic times of a scanning starting signal and a scanning clock signal, an A/D converter for converting said image signal from said image sensor into digital data based on a reference voltage wherein a range of said converting depends on a value of said reference voltage, a voltage selector means for supplying a first reference voltage for detecting said black reference object being lower than a second reference voltage for detecting said manuscript to said A/D converter so that said black reference object is A/D converted with a higher dynamic range, a dividing means for dividing said digital data of the black reference object to a divided value, a subtracter for subtracting the divided digital data of said black reference object from the digital data of the manuscript to obtain a difference therebetween, and issuing digital data indicative of said difference, and a calculator for converting the digital data of the difference into digital data of the same number of bits as said A/D converter.
Claim 7
Dependent Claim
210 words
An image reader for reading a manuscript arranged on a manuscript plane, comprising: a black reference object having a reflection coefficient of substantially zero also arranged on said manuscript plane, a light source for radiating enhanced light in illumination of said black reference object, an image sensor for detecting a multi-gradation image of an object on said manuscript plane, an A/D converter for converting said detected signal of said image sensor into digital data based on a reference voltage, wherein a range of said converting depends on a value of said reference voltage, a voltage selector means for supplying a first reference voltage to said A/D converter for detecting said black reference object, which is lower than a second reference voltage which is supplied to said A/D converter for detecting said manuscript, a dividing means for dividing said enhanced value of the digital data of the black reference object to a divided value, a subtracter for subtracting the divided digital data of said black reference object from the digital data of the manuscript to obtain a difference therebetween, and issuing digital data indicative of said difference, and a calculator for converting the digital data of said difference into digital data of the same number of bits as said A/D converter.
Claim 8
Dependent Claim
210 words
An image reader for reading a manuscript arranged on a manuscript plane, comprising: a black reference object having a reflection coefficient of substantially zero also arranged on said manuscript plane, a light source for radiating enhanced light in illumination of said black reference object, an image sensor for detecting a multi-gradation image of an object on said manuscript plane, an A/D converter for converting said detected signal of said image sensor into digital data based on a reference voltage, wherein a range of said converting depends on a value of said reference voltage, a voltage selector means for supplying a first reference voltage to said A/D converter for detecting said black reference object, which is lower than a second reference voltage which is supplied to said A/D converter for detecting said manuscript, a dividing means for dividing said enhanced value of the digital data of the black reference object to a divided value, a subtracter for subtracting the divided digital data of said black reference object from the digital data of the manuscript to obtain a difference therebetween, and issuing digital data indicative of said difference, and a calculator for converting the digital data of said difference into digital data of the same number of bits as said A/D converter.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-09-08 | 1996-03-09 | 1996-09-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-09-08 | 2000-03-09 | 2000-09-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-09-08 | 2004-03-09 | 2004-09-08 | $7700.00 | Window Closed / Lapsed |