Image reading apparatus and image reading method

• US 20040174575A1
• Filed: 03/01/2004
• Published: 09/09/2004
• Est. Priority Date: 03/03/2003
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation), Toshiba Tec Corporation (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation), Toshiba Tec Corporation (Toshiba Corporation)
• Inventors: Hashizume, Yusuke, Ide, Naoaki
• Granted Patent: US 7,471,426 B2
• Time in Patent Office: Days
• US Class Current: 358/505
• CPC Class Codes: H04N 1/401 Compensating positionally unequal response of the pick-up or reproducing head H04N1/403 takes precedence
• CPC Class Codes: H04N 1/46 Colour picture communication systems
• CPC Class Codes: H04N 1/486 with separate detectors, each detector being used for one specific colour component

Abstract

An image reading apparatus having a color line sensor and a monochromatic line sensor starts to read on the basis of the color reading start position when reading the image of a document in color and starts to read on the basis of the monochromatic reading start position when reading the image of a document in monochrome.

Claims

1. An image reading apparatus which reads images on the reading face of a document in color or in monochrome, the image reading apparatus comprising:

a line sensor which includes a color line sensor for reading a color image and a monochromatic line sensor for reading a monochromatic image different from the color line sensor;

a scanning section on which an optical system for directing light from the reading face of the document to the line sensor is provided;

a driving mechanism which moves the scanning section in a feed direction with respect to the reading face of the document;

a reference plate which is provided in front of the leading edge of the reading face of the document in the feed direction in which the scanning section is moved by the driving mechanism; and

a control section which, when the reading face of the document is read in color, starts to read the reference plate with the color line sensor at the time that the scanning section moved in the feed direction by the driving mechanism reaches a color reading start position for the reference plate, thereby reading the reference plate with the color line sensor, and

which, when the reading face of the document is read in monochrome, starts to read the reference plate with the monochromatic line sensor at the time that the scanning section moved in the feed direction by the driving mechanism reaches a monochromatic reading start position for the reference plate, thereby reading the reference plate with the monochromatic line sensor.

2. The image reading apparatus according to claim 1, wherein the control section, when the reading face of the document is read in color, causes the driving mechanism to move the scanning section in the feed direction and starts to read the reference plate with the color line sensor at the time that the scanning section reaches the color reading start position for the reference plate, thereby reading the reference plate with the color line sensor, and further corrects the data on the reading face of the document read by the color line sensor on the basis of the data on the reference plate read by the color line sensor, and

when the reading face of the document is read in monochrome, causes the driving mechanism to move the scanning section in the feed direction and starts to read the reference plate with the monochromatic line sensor at the time that the scanning section reaches the monochromatic reading start position for the reference plate, thereby reading the reference plate with the monochromatic line sensor, and further corrects the data on the reading face of the document read by the monochromatic line sensor on the basis of the data on the reference plate read by the monochromatic line sensor.

3. The image reading apparatus according to claim 1, wherein

the color line sensor is composed of a plurality of line sensors whose scanning positions are arranged at specific intervals in the feed direction, and

the control section, when the reading face of the document is read in color, causes the driving mechanism to move the scanning section in the feed direction and causes the individual line sensors of the color line sensor to start to read the reference plate in turn at the time that the scanning position of the line sensor whose scanning position is at the rear in the color line sensor in the feed direction reaches the reading start position for the reference plate, thereby reading the reference plate with the color line sensor.

4. The image reading apparatus according to claim 1, wherein

the color line sensor is composed of a plurality of line sensors whose scanning positions are arranged at specific intervals in the feed direction, and

the control section, when the reading face of the document is read in color, causes the driving mechanism to move the scanning section in the feed direction and causes the individual line sensors of the color line sensor to start to read the reference plate in turn at the time that the scanning position of the line sensor whose scanning position is at the head in the color line sensor in the feed direction reaches the reading start position for the reference plate, thereby reading the reference plate with the color line sensor.

5. The image reading apparatus according to claim 1, wherein

the color line sensor is composed of a plurality of line sensors whose scanning positions are arranged at specific intervals in the feed direction, and

the control section, when the reading face of the document is read in color, causes the driving mechanism to move the scanning section in the feed direction and causes the individual line sensors of the color line sensor to start to read the reference plate at the same time at the time that the scanning position of the line sensor whose scanning position is at the rear in the color line sensor in the feed direction reaches the reading start position for the reference plate, thereby reading the reference plate with the color line sensor.

6. An image reading method used in an image reading apparatus which comprises a line sensor which includes a color line sensor for reading a color image and a monochromatic line sensor for reading a mono-chromatic image different from the color line sensor, a scanning section on which an optical system for directing light from the reading face of the document to the line sensor is provided, a driving mechanism which moves the scanning section in a feed direction with respect to the reading face of the document, and a reference plate which is provided in front of the leading edge of the reading face of the document in the feed direction in which the scanning section is moved by the driving mechanism, the image reading method comprising:

when the reading face of the document is read in color, starting to read the reference plate with the color line sensor at the time that the scanning section moved in the feed direction by the driving mechanism reaches a color reading start position for the reference plate and thereby reading the reference plate with the color line sensor; and

when the reading face of the document is read in monochrome, starting to read the reference plate with the monochromatic line sensor at the time that the scanning section moved in the feed direction by the driving mechanism reaches a monochromatic reading start position for the reference plate and thereby reading the reference plate with the monochromatic line sensor.

7. The image reading method according to claim 6, further comprising:

when the reading face of the document is read in color, reading the reference plate with the color line sensor and then correcting the data on the reading face of the document read by the color line sensor on the basis of the data on the reference plate read by the color line sensor, and

when the reading face of the document is read in monochrome, reading the reference plate with the monochromatic line sensor and then correcting the data on the reading face of the document read by the monochromatic line sensor on the basis of the data on the reference plate read by the monochromatic line sensor.

8. The image reading method according to claim 6, wherein

the color line sensor is composed of a plurality of line sensors whose scanning positions are arranged at specific intervals in the feed direction, and

the act of reading the reference plate with the color line sensor is to cause the driving mechanism to move the scanning section in the feed direction and cause the individual line sensors of the color line sensor to start to read the reference plate in turn at the time that the scanning position of the line sensor whose scanning position is at the rear in the color line sensor in the feed direction reaches the reading start position for the reference plate, thereby reading the reference plate with the color line sensor.

9. The image reading method according to claim 6, wherein

the color line sensor is composed of a plurality of line sensors whose scanning positions are arranged at specific intervals in the feed direction, and

the act of reading the reference plate with the color line sensor is to cause the driving mechanism to move the scanning section in the feed direction and cause the individual line sensors of the color line sensor to start to read the reference plate in turn at the time that the scanning position of the line sensor whose scanning position is at the head in the color line sensor in the feed direction reaches the reading start position for the reference plate, thereby reading the reference plate with the color line sensor.

10. The image reading method according to claim 6, wherein

the color line sensor is composed of a plurality of line sensors whose scanning positions are arranged at specific intervals in the feed direction, and

the act of reading the reference plate with the color line sensor is to cause the driving mechanism to move the scanning section in the feed direction and cause the individual line sensors of the color line sensor to start to read the reference plate at the same time at the time that the scanning position of the line sensor whose scanning position is at the rear in the color line sensor in the feed direction reaches the reading start position for the reference plate, thereby reading the reference plate with the color line sensor.