JPH09326906A - Original reader - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent dirt of a white reference board by fitting the white reference board to an original retainer cover and reading a color density reference through a transparent glass plate so as to avoid the color density reference from being concealed by an original even when a size of a reflecting original is large. SOLUTION: A reflection original 45 is placed on an original reception member 24 and adhered to an upper face of an opaque original board 46. Furthermore, an original retainer cover 25 is mounted to a mobile board 23 via a hinge 48 in an opening/closing way and the reflection original 45 is pressed into contact to the upper face of the original board 46 with a transparent glass plate 25a and a support frame 25b. Moreover, a white reference board 50 made of a white ceramic material is fitted to a back side of an end ridge of a read side of the transparent glass plate 25a. Prior to reading of the reflection original 45, a color density of the white reference board 50 is read and stored through the transparent glass plate 25a and the original is read based on it as a reference. Thus, even when the size of the reflection original 45 is large, the white reference board is not concealed by the original and does not get dirt.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a document reading device used for producing a plate making from a print document.

[0002]

2. Description of the Related Art For example, in the case of making a plate from a printing original and printing the original, an original called a scanner is used to convert the original image into an electric signal and read it and perform various signal processing to obtain a desired image before making the original. Reader is in use.

Some small document reading devices move the light source or the reading head with respect to the fixed document. However, when the document is large, the document table on which the document is set is moved to move the sub document. It is known that scanning is performed.

Specifically, a document is set on a document table which can be moved in the horizontal direction, and the document table is moved in the horizontal direction to enter the reading section. Illumination light for reflected originals or illumination light for transmitted originals is applied in a line at a right angle, and the reflected or transmitted light is imaged on a line sensor via a lens system, and the line sensor is scanned in sequence to form an image. Along with reading the signal, the entire original is read by sub-scanning by moving the original table.

In this type of document reading apparatus, a white reference plate is provided on the document table, and the color density of this reference plate is first read and stored before reading the reflection document.
This is used as a white reference and reflected in the subsequent reading of the reflection original.

[0006]

However, in the conventional document reading apparatus, since the white reference plate is provided in the vicinity of the document placing surface of the document table, the document placed on the document placing surface is not printed. In the case of a large format, there is a problem that the white reference plate is hidden by the document and does not function.

In view of the above-mentioned circumstances, it is an object of the present invention to provide an original reading device in which the white reference plate is not hidden by an original.

[0008]

A document reading device according to the present invention is configured so that a document set on a document table is irradiated with light and the light reflected by the document is read by the reading means. In the above, a document pressing cover made of a transparent material for pressing the document on the platen is provided, and within the reading range of the reading means on the document pressing cover,
A white reference plate is attached.

The white reference plate is preferably attached to the back surface of the transparent portion of the document pressing cover. The white reference plate is preferably made of a white ceramic material.

[0010]

According to the present invention, since the white reference plate is attached to the document holding cover, the problem that the white reference plate is hidden by the document is avoided.

Further, when the white reference plate is attached to the back surface of the transparent portion of the document pressing cover, there is no possibility that the white reference plate becomes dirty.

Further, when the white reference plate is made of a white ceramic material, there is an advantage that the color density is stable even during long-term use.

[0013]

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

FIG. 1 is a front view in which a part of an embodiment of a document reading apparatus according to the present invention is omitted, and FIG. 2 is a right side view of the same.

The document reading device 1 includes a document setting portion 2 in which a main body frame 4 constituting the framework of the device is formed low.
And a reading unit 3 formed higher than the above, and the document setting unit 2 has a document table 5 for detachably holding the document, and the document table 5 is slidably provided in the reading unit 3. Has been. In addition, the reading unit 3 has reflection optical fiber bundles 6 and 7 for illuminating a document linearly and a fiber optic bundle 8 for transmitting a transparent document up and down, and above the moving height of the document. A camera 9 having a lens system 15 and a line sensor 16, a rotary drum type filter 10 arranged in front of the camera 9 and a mirror portion 11 are provided, and a lamp box 12 and a substrate box 13 are arranged below. ing.

On the other hand, the original table 5 has a movable base 23 slidably supported by two guide bars 21 and 22.
An original receiving member 24 made of a transparent material, which is swingably mounted on the moving base 23 and has an original placed on the upper surface, and an original receiving member 2 which is openably and closably attached to the moving base 23.
4 is composed of a document pressing cover 25 made of a transparent material which is closed in a state of being pressed against the document. As shown in FIG. 2, the original pressing cover 25 is biased in the opening direction by a damper arm 26.

The movable board 23 is supported by the above-mentioned guide bars 21 and 22 extending from the document setting section 2 to the reading section 3 on the main body frame 4, and is movable, as shown in FIG. Similarly, the ball screw 27 extending from the document setting unit 2 to the reading unit 3 is screwed and linked, and the driving motor 28 rotationally drives the ball screw 27 to control the movement at a constant speed. The drive motor 28 is installed in the reading unit 3 and is linked to the end of the ball screw 27.

Although not shown, an opening / closing cover is installed on the upper surface of the document setting section 2, and the upper side is closed when the document table 5 is moved. In addition, the original pressing cover 2
Although the closed state of 5 is locked by the lock mechanism, this lock release mechanism is arranged on the main body frame 4 side, and the document holding lid 25 can be opened and closed only when the document table 5 is stopped at a predetermined position. It is possible.

On the other hand, in the reading section 3, a pair of optical fiber bundles 6 and 7 for reflecting originals is installed above the original table 5 that has moved as described above, and one optical fiber for transmitting originals is provided below. A bundle 8 is installed to illuminate the originals linearly. Each of the optical fiber bundles 6 to 8 is composed of a large number of optical fibers, the illumination end of which is linearly arranged in a line, and the other end of which is bundled into a cylindrical shape, and a lamp box 12 arranged below the reading unit 3. The three light source lamps (not shown) are installed to face each other. Further, in front of the linear illumination end, the light flux is adjusted through the cylindrical rod-shaped lenses 31 to 33 and is irradiated onto the document. Three light source lamps are collectively arranged in the lamp box 12, and the inside of the lamp box 12 is cooled by a cooling fan.

First optical fiber bundle 6 for illuminating reflected originals
Are inclined so that the illumination end thereof illuminates the surface of the document from the front at an angle of 45 ° in the traveling direction of the document. The second reflection original illuminating optical fiber bundle 7 has its illuminating end installed horizontally from the front to the original traveling direction, and a reflecting mirror 34 obliquely installed obliquely downward in the facing portion, and is provided in the advancing direction. It is arranged so as to illuminate the surface of the original from a diagonally 45 ° rear side.

The optical fiber bundle 8 for illuminating a transmissive original has its illuminating end installed horizontally from the front with respect to the traveling direction of the original, and a reflecting mirror 35 inclined obliquely upward is provided at the facing portion and provided from the bottom to the top. Illuminate the original through illumination.

A mirror portion 11 is provided above the illumination position of the original document by the optical fiber bundles 6 to 8 for original document illumination.
The mirror portion 11 is installed at the upper end corner of the main body frame 4 of the reading portion 3, and the reflecting surface of the mirror portion 11 reflects the light from below in a direction substantially parallel to the document traveling direction, but is incident. The light is not reflected in the direction perpendicular to the light, but the optical axis after the reflection is set to be inclined slightly downward with respect to the horizontal direction (the moving direction of the document).

In the optical path reflected by the mirror section 11,
Rotating drum filter 10, lens system 1 for camera 9
5, the line sensor 16 is installed in this order, these are fixed to the mounting frame 37, and this mounting frame 37 is fixed to the main body frame 4 in an inclined manner. The mounting position of the camera 9 is adjustable.

In the camera 9, the lens system 15 is provided on the lens barrel, the optical path is divided at the focal position through the half prism 39, and the line sensors 16 are alternately installed at the respective focal points so that signals on a straight line are continuous. It is configured to be obtained by. Main scanning for sequentially reading the signals of the respective sensors in the line sensor 16 is performed by a control board (not shown), and the control board is the board housing section 4 at the back of the camera.
0, an adjustment space for absorbing variations in the focal length of the lens system 15 is provided between the camera 9 and the substrate housing portion 40, and the camera 9 is moved and adjusted in the optical axis direction.

In the rotary drum type filter 10, both side rotary plates of the cylindrical drum are pivotally supported by a shaft 10a, and a plurality of (for example, 6) filters 41 are arranged at equal intervals in the cylindrical portion. Filter 4 stopped in front of the lens
The optical filter is provided so that the optical axis passes through the filter gap on the cylindrical surface on the opposite side to 1, and the desired filter 41 can be used by controlling the rotational position thereof.

Next, FIG. 3 is a schematic perspective view of the document reading device 1 with the document pressing lid 25 closed, and FIG. 4 is a schematic perspective view of the document table 5 with the document pressing lid 25 opened. Are shown respectively. 5 is a plan view of a main part of the document table 5, and FIG. 6 is a sectional view taken along line VI-VI of FIG. It should be noted that in order to facilitate understanding, the white reference plate is shown in an enlarged form with respect to the actual size in FIGS. 3 and 4.

A document receiving member 24 made of a transparent glass plate
The shaft 44 provided on the support frame 43 of the movable base 23
Since it is pivotally supported, it is provided so as to be swingable around an axis parallel to the moving direction of the document table 5, and the reflection document 45 is an opaque document sheet mounted on the document receiving member 24. It is attached to the upper surface of 46. Further, the document receiving member 24 can be detached from the moving base 23, and a grip 47 is provided on the support frame 43 as shown in FIG.

The original pressing cover 25 mounted on the movable base 23 via the hinge 48 so as to be openable and closable is a transparent glass plate 25 for pressing the reflective original 45 onto the original mount 46 at its closed position.
a and a support frame 25b that supports the peripheral edge of the transparent glass plate 25a.
5 and 6 are provided on the back surface of the edge portion of the side a of the reading section 3a.
As is clear from the above, a substantially square white reference plate 50 made of a white ceramic material is attached to the center position of the above-mentioned edge portion (center position in the left-right direction in FIG. 2).
Further, on the back surface of the transparent glass plate 25a, the white reference plate 5
On the front side (the left side in FIGS. 5 and 6) of the rear edge 0 (the right end edge in FIGS. 5 and 6) of 0, the black strip-shaped member 51 extending in the direction perpendicular to the paper surface of FIG. 6 is the white reference plate. It is attached as 50 background members.

The white reference plate 50 as described above is used for the document pressing lid 2.
Since it is attached to the reflective original 45, the color density of the white reference plate 50 is first read and stored through the transparent glass plate 25a prior to reading the reflective original 45, and this is used as a white reference, and the reflective original 45 after that is read. Can be reflected in the reading of.

Further, since the white reference plate is attached to the 50 document holding cover 25, the problem that the white reference plate 50 is hidden by the document 45 is avoided even when the reflection document 45 is a large plate.

Further, the white reference plate 50 is used as the original holding cover 25.
Since it is attached to the back surface of the transparent glass plate 25a, there is no possibility that the white reference plate 50 becomes dirty.

Further, since the white reference plate 50 is made of a white ceramic material, there is an advantage that the color density is stable even during long-term use.

In the present embodiment, the white reference plate 50 is located at the center position on the back surface of the edge of the transparent glass plate 25a of the document holding lid 25 on the reading unit 3 side (the center position in the left-right direction in FIG. 2). However, the mounting position of the white reference plate 50 does not necessarily have to be the central position as long as it is within the reading range of the reading means on the document pressing lid 25.

[Brief description of drawings]

FIG. 1 is a front view showing a document reading apparatus according to an embodiment of the present invention with a cover and the like omitted.

[Figure 2] Same right side view

FIG. 3 is a schematic perspective view of the document reading device with the document pressing lid closed.

FIG. 4 is a schematic perspective view of the document table with the document pressing lid opened.

FIG. 5 is a plan view of an essential part of the document table 5.

FIG. 6 is a sectional view taken along line VI-VI in FIG.

[Explanation of symbols]

 1 Original Reading Device 2 Original Setting Section 3 Reading Section 4 Body Frame 5 Original Plate 6,7 Optical Fiber Bundle for Reflecting Original Illumination 8 Optical Fiber Bundle for Transmissive Original Illumination 9 Camera 10 Rotating Drum Filter 11 Mirror 12 Lamp Box 15 Lens System 16 Line sensor 23 Moving base 24 Original receiving member 25 Original pressing lid 27 Ball screw 34 Reflecting mirror 37 Mounting frame 39 Half prism 45 Reflective original 46 Original mount 50 White reference plate

Claims (3)

[Claims] 1. A document reading apparatus configured to irradiate a document set on a document table with light and to read the reflected light from the document by a reading means, wherein the document is pressed onto the document table. And a white reference plate mounted within the reading range of the reading means on the original document holding lid. 2. The document reading apparatus according to claim 1, wherein the white reference plate is attached to a back surface of a transparent portion of the document pressing lid. 3. The white reference plate is made of a white ceramic material.
Document reading device as described.