Contact-type image sensor module and image reading apparatus using the module

• US 20050006562A1
• Filed: 02/05/2004
• Published: 01/13/2005
• Est. Priority Date: 07/08/2003
• Status: Active Grant

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Endo, Takafumi, Sugihara, Hirohisa
• Granted Patent: US 7,166,827 B2
• Time in Patent Office: Days
• US Class Current: 250/208.100
• CPC Class Codes: H01L 27/14625 Optical elements or arrangements associated with the device
• CPC Class Codes: H01L 27/14678 Contact-type imagers

Abstract

In color reading including an infrared light source, light reflected by a document focuses on a light-receiving part of a sensor IC with different conjugate lengths, due to color aberration of the rod-lens. Since the wavelength of the infrared light is relatively long, the deterioration of the reading resolution appears to be extensive. Here, when reading a document such as a valuable security or a paper bill, a defocusing phenomenon has been prevented, and when reading by infrared light, a high accurate reading characteristic has been realized. As a solution, light is irradiated from a light output window (101a) of a light source (101) and reflected by a document (8), and an infrared light shielding area is provided on a bottom face of a glass (51) placed in an optical path of the light reflected by the document (8), between the document (8) and a sensor IC (3).

Claims

1. A contact-type image sensor module comprising:

a light source for irradiating two or more sorts of light including infrared light on a document;

a lens for focusing light reflected from the document;

a light-receiving part for receiving the reflected light focused by the lens;

a housing for containing at least the lens and the light-receiving part; and

a transparent element to which the document draws near or comes into contact with, the transparent element supported by the housing, and provided on an area thereof through which the reflected light passes with infrared light shielding extending to a width of 0.1 through 0.4 mm in a direction orthogonal to that in which the document travels.

2. A contact-type image sensor module as recited in claim 1, wherein:

the transparent element has at least a two-tier structure;

the transparent element on a side thereof a document face draws near is hemispherical; and

the infrared light shielding is provided on the planar side of the hemispherical part of the transparent element.

3. A contact-type image sensor module comprising:

a light source for irradiating two or more sorts of light including infrared light on a document;

a lens for focusing reflected light from the document;

a light-receiving part for receiving the reflected light focused by the lens;

a housing for containing at least the lens and the light-receiving part;

a transparent element for passing through the reflected light; and

a document guide to which the document draws near or comes into contact with, the document guide is supported by the housing attachably to or detachably from the housing, and fixes the transparent element.

4. A contact-type image sensor module as recited in claim 3, wherein the document guide has a slit in the proximity of a reading position thereof.

5. A contact-type image sensor module comprising:

a light source for irradiating two or more sorts of light including infrared light on a document;

a lens for focusing reflected light from the document;

a light-receiving part for receiving the reflected light focused by the lens;

a housing for containing at least the lens and the light-receiving part; and

a document guide to which the document draws near or comes into contact with, the document guide is supported by the housing attachably to or detachably from the housing.

6. A contact-type image sensor module as recited in claim 5, wherein the document guide has a slit in the proximity of a reading position thereof.

7. A contact-type image sensor module comprising:

a light source for irradiating two or more sorts of light including infrared light on a document;

a lens for focusing reflected light from the document;

a light-receiving part for receiving the reflected light focused by the lens;

a housing for containing at least the lens and the light-receiving part;

a transparent element placed on a part of an area of the element for passing through the reflected light; and

a document guide for fixing the transparent element, the document guide to which the document draws near or comes into contact with, and supported by the housing.

8. A contact-type image sensor module as recited in claim 7, wherein the document guide has a slit in the proximity of a reading position thereof.

9. An image reading apparatus comprising:

a contact-type image sensor module having;

a light source for irradiating two or more sorts of light including infrared light on a document;

a lens for focusing light reflected from the document;

a light-receiving part for receiving the reflected light focused by the lens;

a housing for containing at least the lens and the light-receiving part; and

a transparent element to which the document draws near or comes into contact with, the transparent element supported by the housing, and provided on an area thereof through which the reflected light passes with infrared light shielding extending to a width of 0.1 through 0.4 mm in a direction orthogonal to that in which the document travels, wherein;

optical axes of the two contact-type image sensor modules placed opposite each other are made to coincide;

the housings of the contact-type image sensor modules are fixed to each other with a single metallic part; and

both faces of the document are read out with the document being conveyed into a gap between the opposing document guides.

13. An image reading apparatus as recited in claim 9, wherein:

the contact-type image sensor having;

the transparent element has at least a two-tier structure;

the transparent element on a side thereof a document face draws near is hemispherical; and

the infrared light shielding is provided on the planar side of the hemispherical part of the transparent element.

10. An image reading apparatus comprising:

a contact-type image sensor module having;

a light source for irradiating two or more sorts of light including infrared light on a document;

a lens for focusing reflected light from the document;

a light-receiving part for receiving the reflected light focused by the lens;

a housing for containing at least the lens and the light-receiving part;

a transparent element for passing through the reflected light; and

a document guide to which the document draws near or comes into contact with, the document guide is supported by the housing attachably to or detachably from the housing, and fixes the transparent element, wherein;

optical axes of the two contact-type image sensor modules placed opposite each other are made to coincide;

the housings of the contact-type image sensor modules are fixed to each other with a single metallic part; and

both faces of the document are read out with the document being conveyed into a gap between the opposing document guides.

14. An image reading apparatus as recited in claim 10, wherein:

the contact type image sensor comprising the document guide having a slit in the proximity of a reading position thereof.

11. An image reading apparatus comprising:

a contact-type image sensor module having;

a light source for irradiating two or more sorts of light including infrared light on a document;

a lens for focusing reflected light from the document;

a light-receiving part for receiving the reflected light focused by the lens;

a housing for containing at least the lens and the light-receiving part; and

a document guide to which the document draws near or comes into contact with, the document guide is supported by the housing attachably to or detachably from the housing, wherein;

optical axes of the two contact-type image sensor modules placed opposite each other are made to coincide;

the housings of the contact-type image sensor modules are fixed to each other with a single metallic part; and

both faces of the document are read out with the document being conveyed into a gap between the opposing document guides.

15. An image reading apparatus as recited in claim 11, wherein:

the contact type image sensor comprising the document guide having a slit in the proximity of a reading position thereof.

12. An image reading apparatus comprising:

a contact-type image sensor module having;

a light source for irradiating two or more sorts of light including infrared light on a document;

a lens for focusing reflected light from the document;

a light-receiving part for receiving the reflected light focused by the lens;

a housing for containing at least the lens and the light-receiving part;

a transparent element placed on a part of an area of the element for passing through the reflected light; and

a document guide for fixing the transparent element, the document guide to which the document draws near or comes into contact with, and supported by the housing, wherein;

optical axes of the two contact-type image sensor modules placed opposite each other are made to coincide;

the housings of the contact-type image sensor modules are fixed to each other with a single metallic part; and

both faces of the document are read out with the document being conveyed into a gap between the opposing document guides.

16. An image reading apparatus as recited in claim 12, wherein:

the contact type image sensor comprising the document guide having a slit in the proximity of a reading position thereof.