JPH05236204A - Scanner - Google Patents

Abstract

PURPOSE:To realize the scanner used for an automatic original feeder with a simple configuration. CONSTITUTION:When the automatic original feeder is in use, the optical system is set to the operating mode 10a of the automatic original feeder and a focus of a lens at the original side is moved up to an upper projection face of an auxiliary glass 3 by inserting the auxiliary glass 3 thicker than an original platen glass 1 into an optical system. In this case, the original 2a passes on the surface of the auxiliary glass 3 and is lighted by a lighting device 6 and an original image is led to a lens 8 by a mirror 7 and formed onto an image sensor 9. The original 2a passing through the auxiliary glass 3 is recovered into the automatic original feeder by a step difference between the auxiliary glass 3 and the original platen glass 1 and a paper scooper 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to document feeding of an automatic document feeder for a scanner using an image sensor or the like.

[0002]

2. Description of the Related Art Conventionally, in a scanner equipped with an automatic document feeder, the following methods have been studied as means for collecting documents from the platen glass surface into the automatic document feeder. FIG. 5 is a first configuration diagram of a portion for collecting a document in the automatic document feeder in the conventional apparatus. The original 2a is fed while being pressed against the reading glass 11 for the automatic original feeding device by the rotation of the roller 4, the original 2a is illuminated by the illuminating device 6 at that time, and the illuminated original image is guided to the lens 8 by the mirror 7 to form an image. Document 2 which is imaged on the sensor 9 and read, and which has passed through the reading glass 11
The a is collected in the automatic document feeder by the paper scoop 5 inserted in the recess of the case beam 12.

FIG. 6 is a second structural view of the portion for collecting the original document in the automatic document feeder, and the original document 2a is fed while being pressed against the original table glass 1 by the rotation of the roller 4, and at that time, the illuminating device 6 is provided. The original 2a is illuminated by the light source, and the illuminated original image is guided by the mirror 7 to the lens 8 to be imaged and read by the image sensor 9. The original 2a which has passed the reading position is inserted into the original scoop groove 13 of the original glass 1. The collected paper scraps 5 are collected in the automatic document feeder.

FIG. 7 is a third structural view of the portion for collecting the original document in the automatic document feeder, and the original document 2a is pressed against the original guide transparent sheet 25 attached to the automatic document feeder by the rotation of the roller 4. While being sent, the original 2a is illuminated by the illuminating device 6 through the original guide transparent sheet 25 and the original table glass 1, and the illuminated original image is guided to the lens 8 by the mirror 7 to be imaged on the image sensor 9 and read. The original 2a that has passed the reading position is
The transparent sheet 25 for document guide collects it in the automatic document feeder.

[0005]

In the document collecting means of the conventional automatic document feeder, in the first conventional example, since the paper scoop is inserted between the platen glass and the glass for the automatic document feeder, A beam shape that closes the space between the two glasses is required, and when the case and the beam are integrated, molding defects such as insufficient filling and warpage are likely to occur in the beam portion, and the beam shape needs to be a separate body. Further, the beam shape and the glass for the automatic document feeder are elongated in the main scanning direction, and the periphery of the automatic document feeder becomes weak.

Further, the second conventional example has a drawback that the groove processing of the original glass is very expensive because the original table glass itself is provided with the groove.

In the third conventional example, when the lens focus is set on the surface of the normal original for reading the normal original,
When using the automatic document feeder, the transparent sheet for document guide is sandwiched between the platen glass and the document, so the lens focus shifts by the thickness of the sheet, and conversely the document is focused when using the automatic document feeder. In that case, there is a drawback that the lens focus is usually deviated when reading the original.

[0008]

A scanner of the present invention comprises an optical system unit including an illuminating device, a lens, and an image sensor. An original is placed on a transparent plate for an original, and the optical system unit is moved in the sub-scanning direction. By the first method of moving and reading the original, and by moving the optical system unit outside the moving range of the optical system unit at the time of reading by the first method, and moving the original in the sub-scanning direction by the automatic original feeding device. In the case of having a second method for reading, and in the case of reading by the second method, in a scanner using a dedicated reading window, the original reading window is used as the dedicated reading window at the end of the transparent plate for the original. A second transparent plate having a thickness protruding from the upper surface of the transparent plate is provided.

Further, the paper scooping means used in reading the original by the second method is formed adjacent to the step portion between the original transparent plate and the second transparent plate.

Further, it is characterized in that the step portion is used as a position reference of the document arrangement when the document is read by the first method.

Further, the lower portion of the second transparent plate is projected from the lower surface of the original transparent plate.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a block diagram of a method for collecting a document in an automatic document feeder in a scanner of the present invention.

In the case of reading without using the automatic document feeder, the optical system is in a state such as the normal reading state 10b, and the reading in the sub-scanning direction is performed to read the original 2b.
Illuminated by the illumination device 6, the original image is guided by the mirror 7 to the lens 8 and is formed on the image sensor 9. When the automatic document feeder is used, the optical system is in the automatic document feeder use state 10a, and the original 2a is pushed by the rotation of the roller 4 against the auxiliary glass 3 which is a transparent plate, and then the auxiliary glass is moved. Document 2a that passed
Are collected in the automatic document feeder by the step between the auxiliary glass 3 and the platen glass 1 and the paper scoop 5. If the above-mentioned auxiliary glass 3 is not provided, the original 2a is sandwiched between the paper scoop 5 and the original glass 1, and the original 2a cannot be separated from the original glass 1 and cannot be collected.

FIG. 2 is a first detailed view of the scooped portion of the document of the automatic document feeder. The white reference is on the lower surface of the auxiliary glass 3 and on the white reference printing surface 23 which does not hinder reading or illumination. The original scale that is printed and serves as a reference for original placement is also printed on the upper surface of the auxiliary glass 3 and on the original scale printing surface 22 that does not hinder reading or illumination. The document position is determined by pressing the document edge against the edge. A protective film 26 is coated between the auxiliary glass 3 and the platen glass 1 to prevent the glass from being damaged during transportation.

FIG. 3 is a second detailed view of the scooping portion of the document of the automatic document feeder, which is a part 2 for both scale and white reference.
4 is a position where the upper surface is the scale and the lower surface is the white reference, and when the original 2b is placed on the original table glass 1, the scale can be confirmed through the auxiliary glass 3 and the reading and illumination are not hindered. When the original 2b is installed, the original position is determined by pressing the edge of the original against the edge of the auxiliary glass 3.

FIG. 4 shows the principle of changes in the lens focus when the automatic document feeder is used and during normal reading.

The lens optical path 14 at the time of normal reading is refracted by the original platen glass 1 at the position of the refraction point 19 and becomes like an in-glass optical path 16, and an image is formed on the surface of the original platen glass 1. In this state, if the optical path 14 is refracted like the optical path 16 at the position of the overhead line 21, the optical path becomes like the overhead optical path 17. In order to obtain an optical path similar to the optical path 17, the optical path 15 is refracted by the auxiliary glass 3 at the refraction point 20 to obtain the in-glass optical path 18, and the auxiliary glass 3 is projected to the upper surface in order to press the document at the focal point of the optical path 18. Let

According to the above principle, it is possible to obtain the optimum lens focus position both when the automatic document feeder is used and when it is not used.

[0019]

According to the present invention, the original is fed inside the automatic document feeder without forming a groove in the original glass and without providing a separate glass in addition to the original table glass at positions separated in the sub-scanning direction. Since it can be collected at a very low cost, it is very inexpensive and easy to process.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of the configuration of a scanner according to the present invention.

FIG. 2 is a detailed view of a scanner according to the present invention.

FIG. 3 is a detailed view of a scanner according to the present invention.

FIG. 4 is an optical principle diagram of a scanner according to the present invention.

FIG. 5 is an explanatory diagram of a configuration of a conventional scanner.

FIG. 6 is an explanatory diagram of a configuration of a conventional scanner.

FIG. 7 is an explanatory diagram of a configuration of a conventional scanner.

[Explanation of symbols]

 1 Original Plate Glass 2a Original for Automatic Document Feeder 2b Normal Scanning Original 3 Auxiliary Glass 4 Automatic Document Feeder Roller 5 Automatic Document Feeder Paper Scooping 6 Illuminator 7 Mirror 8 Lens 9 Image Sensor 10a Used Automatic Document Feeder 10b Normal Reading state 11 Scanning glass for automatic document feeder 12 Case beam 13 Document rake groove 14 Lens light path during normal reading 15 Lens light path during automatic document feeding 16 Optical path inside glass 17 Aerial optical path 18 Optical path inside glass 19 Refraction point 20 Refraction point 21 Overhead line 22 Original scale printing surface 23 White reference printing surface 24 Scale and white reference dual use parts 25 Original guide transparent sheet 26 Protective film

Claims (4)

[Claims] 1. A first method comprising an optical system unit including an illuminating device, a lens and an image sensor, placing a document on a transparent plate for a document, and moving the optical system unit in a sub-scanning direction to read the document. A second method of reading the original by moving the optical system unit outside the movement range of the optical system unit at the time of reading by the first method and moving the original in the sub-scanning direction by the automatic original feeding device. In the case of reading by the second method, in a scanner using a dedicated reading window, as the dedicated reading window, a first reading window having a thickness protruding from the upper surface of the original transparent plate is provided at the end of the original transparent plate. A scanner having two transparent plates. 2. A paper scooping means used for reading an original by the second method is formed adjacent to a step between the original transparent plate and the second transparent plate. The scanner according to claim 1. 3. The scanner according to claim 1, wherein the stepped portion is used as a position reference of the document arrangement when the document is read by the first method. 4. The scanner according to claim 1, wherein the lower portion of the second transparent plate projects from the lower surface of the original transparent plate.