JPH07107283A - Picture reader - Google Patents

Abstract

PURPOSE:To provide a picture reader capable of obtaining the white reference data corresponding to the time change of a magnification image sensor without attaching dusts and dirt due to the original reading in spite of the reading original. CONSTITUTION:A white reference board 2, arm 5 to which the white reference board is connected to be rotated freely around one point, rotating member 4 coupled with the arm, and motor 5 which drives the rotating member are provided. When the white reference data are not read, the white reference board 3 is located aside the reading position of the image sensor 1 and the white reference board 3 is moved on the image sensor 1 at the time of the white reference data reading. Thus, the white reference data can be taken every time when the originals are read in spite of the type of original and no dirt or dust is attached to the white reference board due to the original reading. Thus, the accurate shading correction can be performed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a document moving type image reading apparatus using a 1x image sensor such as a facsimile or a scanner.

[0002]

2. Description of the Related Art A document moving type image reading apparatus using an equal-magnification image sensor has hitherto been disclosed in, for example, Japanese Patent Laid-Open No. 4-2.
263 is an image reading apparatus.

An image reading apparatus of a moving original type using an equal-magnification image sensor and using an equal-magnification image-forming system as the equal-magnification image sensor is generally illustrated in FIG. Is configured to. In the figure, 1 is an equal-magnification image sensor, 2 is a platen roller, and 21.
1 is a cover glass of a 1 × image sensor, 22 is a 1 × imaging lens of the 1 × image sensor 1, and 23 is a 1 × image.
It is an LED light source of the di-sensor 1. In this image reading apparatus, electrical scanning in the main scanning direction of the same-magnification image sensor 1 and mechanical sub-scanning of a document conveying system including a paper feeding roller, a paper discharging roller, etc., not shown. Can read a two-dimensional image. Conventionally, there are the following three methods for obtaining the white reference data for the shading correction of the image reading apparatus having this configuration.

First, with the platen roller 1 as a white reference,
A method in which the data read by the platen roller before the original is conveyed to the normal-size sensor reading position is used as white reference data.

Second, a method of detecting the white portion at the beginning of the original and using the read data of the beginning portion as the white reference data.

Thirdly, when the image reading apparatus is shipped from the factory, the data read from the white reference plate is recorded in a memory such as a ROM, and the data read from the memory is read from the memory when the image is read. -The method used as a data.

[0007]

However, the above three methods have the following problems.

In the first method, the white platen roller becomes dirty and dust is attached with the reading of the original document and cannot be used as a white reference.

The second method cannot deal with an original whose head portion is not white.

In the third method, it is not possible to cope with the light source light quantity of the same-magnification image sensor and the change in sensor sensitivity with time.

The present invention has been made in order to solve the above-mentioned problems, and it is free from dust and dirt associated with reading an original regardless of the original to be read, and is capable of coping with a change with time of an equal-magnification image sensor. It is an object of the present invention to provide an image reading device that can acquire reference data.

[0012]

In order to achieve the above object, the present invention is configured as follows.

As a first means, a white reference plate, an arm in which the white reference plate is rotatably connected about one point, a rotating member integrated with the arm, and a rotating member are provided. A driving motor is provided, and the white reference plate is set to a position other than the reading position of the 1x image sensor when the white reference data is not read, and the white reference plate is read at the 1x image when reading the white reference data. -Move to above the sensor.

As a second means, a white reference plate, an arm in which the white reference plate is rotatably connected about one point, a rotary member integrated with the arm, and a rotary member are provided. A motor for driving and a guide for guiding the white reference plate onto the 1x image sensor are provided, and the white reference plate is set to a position other than the reading position of the 1x image sensor except when reading the white reference data. Alternatively, the white reference plate may be moved onto the same-magnification image sensor when reading the white reference data.

As a third means, a white reference plate, an arm in which the white reference plate is rotatably connected about one point, a rotating member integrated with the arm, and a rotating member are provided. A driving motor and a guide that guides the white reference plate onto the 1x image sensor so as not to come into close contact with the 1x image sensor are provided. Set to a position other than the position of the image sensor and set the white reference
The white reference or the like may be moved to the same-size image sensor when reading the data.

As a fourth means, a white reference plate, an arm in which a white reference plate is rotatably connected about one point, a rotating member integrated with the arm, and a rotating member are provided. A motor for driving, a guide for guiding the white reference plate onto the 1x image sensor so as not to be in close contact with the 1x image sensor, and a shading plate for blocking flare light incident on the 1x image sensor are provided. When the white reference data is not read, the white reference plate is set to a position other than the reading position of the same-size image sensor, and the white reference plate is read in the same-size image when reading the white reference data.
It may be possible to move it over the sensor.

As a fifth means, a white reference plate, an arm in which the white reference plate is rotatably connected about one point, a rotary member integrated with the arm, and a rotary member are provided. A driving motor and a rubber with a rounded shape that can guide the white reference plate on the white reference plate so that the white reference plate does not come in close contact are provided on the white reference plate. It is also possible to set the white reference plate at a position other than the reading position of the 1x image sensor and move the white reference plate onto the 1x image sensor when reading the white reference data.

[0018]

Embodiments of the present invention will be described below in detail with reference to the drawings.

A first embodiment of the present invention will be described with reference to FIG. In FIG. 1, 1 is a 1 × image sensor, 2 is a platen roller for pressing a document (not shown) against the 1 × image sensor 1 with a constant pressure, 3 is a white reference plate,
4 is a transmission system such as a gear, 5 is an arm connecting the white reference plate and the gear, 6 is a drive system such as a motor for driving the gear, 21
Is a cover glass of the 1x image sensor 1, 22 is a 1x imaging system of the 1x image sensor 1, 23 is an LED light source part of the 1x image sensor 1, and 24 is a sensor part of the 1x image sensor 1. Further, the gear 4 and the arm 5 are integrated, and the white reference plate 3 and the arm 5 are connected so that the white reference plate 3 can rotate around a bearing 7 which is a connecting portion with the arm. A document is two-dimensionally read by electrical main scanning of the image sensor 1 of the same size and mechanical sub-scanning by a document conveying system including a paper feed roller, a paper roller and the like (not shown).

In the present embodiment, when the white reference data is taken in, the motor 6 is rotated to guide the white reference plate 3 onto the same-magnification image sensor 1 and the data read by the white reference plate 3 may be used as the white reference data. it can.

When reading a document, the motor 6 is used.
By rotating the white reference plate 3, the white reference plate 3 is moved from above the same-magnification image sensor 1 to avoid a position other than the reading position of the same-magnification image sensor.

With this configuration, since the white substrate 3 is not in contact with the original document, dirt and dust on the original document are prevented from adhering to the white substrate 3.

For this reason, regardless of the type of the original, the dirt associated with reading the original does not adhere, and the white reference data can be taken into the original every time the original is read.

The second embodiment of the present invention will be described with reference to FIG. In FIG. 2, the same components as those in FIG. 1 are given the same numbers. The difference between this embodiment and the first embodiment is that guides 8 for smoothly guiding the white reference plate onto the same-size image sensor are installed on both sides of the same-size image sensor. With this configuration, the same effect as that of the first embodiment can be obtained, and since the white reference plate 3 can be smoothly guided onto the image sensor of the same size, mechanical failure is reduced.

A third embodiment of the present invention will be described.
The difference between this embodiment and the second embodiment is that the guide 8 in FIG. 2 is installed so that the white reference plate 3 and the glass surface of the image sensor of the same size have a space of, for example, about 0.1 mm. . With this configuration, the same effect as that of the second embodiment can be obtained, and the white surface of the white reference plate 3 does not adhere to the glass surface of the image sensor 1 of the same size, and the white reference data is always taken in on the white surface with no contamination. be able to.

A fourth embodiment of the present invention will be described with reference to FIG. In FIG. 3, the same components as those in FIGS. 1 and 2 are designated by the same reference numerals. In this embodiment, as in the third embodiment, the guide 8 is installed so that the white substrate 3 and the glass surface 10 of the normal-size image sensor have a space of, for example, about 0.1 mm. The difference between this embodiment and the third embodiment is that the light shielding plate 9 is provided. With this configuration, the third
The effect similar to that of the above embodiment can be obtained, and flare light incident on the equal-magnification image sensor 1 can be shielded from the interval between the equal-magnification image sensor 1 and the white reference plate 3, and more accurate white reference data can be captured. be able to.

The fifth embodiment of the present invention will be described with reference to FIG. In FIG. 4, the same components as those in FIGS. 1, 2 and 3 are designated by the same reference numerals. In FIG. 4, reference numeral 10 denotes a rubber having a roundness. The difference from the embodiment of FIG. 4 is that the guide 8 and the light shielding plate 9 are omitted and the rubber 10 having a roundness is attached to the white reference plate. With this configuration, the rubber 10 guides the white reference plate 3 onto the 1x image sensor 1, creates a gap between the 1x image sensor 1 and the white reference plate 3, and blocks flare light incident from the gap. You can As a result, the effect of the fourth embodiment is obtained, the structure is simplified, and the cost is reduced.

[0028]

According to the first aspect of the present invention, since the white reference plate is used, the white reference data can be read every time the original is read, regardless of the type of the original. Further, since the white reference plate does not come into contact with the document, dirt and dust accompanying the document reading will not adhere to the white reference plate.
Therefore, accurate shading correction can be performed.

According to the second aspect of the invention, the same effect as that of the first aspect of the invention can be obtained, and further, the guide is used to guide the white substrate to the glass surface of the image sensor of the same size. Performance improves and fewer failures occur.

According to the third aspect of the invention, the same effect as that of the second aspect of the invention can be obtained, and further, when the white reference plate is moved onto the glass surface of the image sensor of the same size when the white reference data is taken in. In addition, since there is a gap between the glass surface of the 1x image sensor and the white reference plate, even if the white reference data is taken in, the lax surface of the 1x image sensor is dirty and dust adheres to the white reference plate. There is no. Therefore, more accurate shading correction can be performed.

According to the invention described in claim 4, it is possible to obtain the same effect as that of the invention described in claim 3, and further, the light enters the same-magnification image sensor through the gap between the glass surface of the same-magnification image sensor and the white reference plate. Since the light blocking plate for blocking the flare light is provided, the white reference data can be input without being affected by the flare light. Therefore, more accurate shading correction can be performed.

According to the invention of claim 5, it is possible to obtain the same effect as that of the invention of claim 4, and further, by attaching a rubber to the white reference plate so as to function as both a guide and a light-shielding plate. Can be simplified and the cost can be reduced.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a sectional view showing a second embodiment of the present invention.

FIG. 3 is a sectional view showing a fourth embodiment of the present invention.

FIG. 4 is a sectional view showing a fifth embodiment of the present invention.

FIG. 5 is a sectional view showing a conventional image reading apparatus.

[Explanation of symbols]

 1 1 × image sensor 2 Platen roller 3 White reference plate 4 Rotating member 5 Arm 6 Motor 7 Bearing 8 Guide 9 Light-shielding plate 10 Rounded rubber 21 Cover glass 22 Double imaging system 23 LED light source part 24 Sensor part

Claims (5)

[Claims] 1. A document moving type image reading apparatus using an equal-magnification image sensor, a white reference plate, an arm connecting the white reference plate rotatably around one point, and A rotary member integrated with the arm and a motor for driving the rotary member are provided, and the white reference plate is set at a position other than the reading position of the equal-magnification image sensor except when the white reference data is read. An image reading apparatus, wherein the white reference plate is moved to a position, and the white reference plate is moved onto the same-magnification image sensor when reading white reference data. 2. The image reading device according to claim 1, further comprising a guide for guiding the white reference plate onto the same-size image sensor. 3. The image reading device according to claim 1, further comprising a guide for guiding the white reference plate onto the image sensor of the same size so as not to be in close contact with the image sensor of the same size. 4. The image reading apparatus according to claim 1, wherein a guide for guiding the white reference plate onto the same-magnification image sensor so as not to be in close contact with the same-magnification image sensor, and a same-magnification image sensor.
An image reading apparatus comprising: a light-shielding plate that shields flare light incident on the disensor. 5. The image reading apparatus according to claim 1, wherein the white reference plate is provided with a rounded rubber that can guide the white reference plate on the same-size image sensor so that the white reference plate does not adhere to the white reference plate. Image reading device.