JP3078160B2 - Image reading device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image reading apparatus such as a handy scanner.

[0002]

2. Description of the Related Art Conventionally, an image reading apparatus such as a handy scanner is based on a difference between white reference document data and black reference document data in order to correct illumination unevenness and sensitivity unevenness of a photoelectric conversion element. To normalize the read data located in the middle
Ding correction is performed.

FIG. 9 is an external perspective view showing a conventional handy scanner, and FIG. 10 is a sectional view taken along the line AA of FIG.

The basic configuration of the handy scanner 1 is shown in FIG.
As shown in FIG. 1, a housing 4 on which the line sensor 2 is mounted and moves on the original 3 in the direction of arrow B which is the sub-scanning direction.
A line sensor 2 for irradiating the reading position 5 with light;
It comprises a lens 7 and a photoelectric conversion element 8. The lenses 7 and the photoelectric conversion elements 8 are juxtaposed in the main scanning direction in an arrow CD direction by an amount corresponding to the number of pixels for one line. The lens 7 is provided so that the reflected light from the reading position 5 converges on the photoelectric conversion element 8.

The housing 4 is provided with rollers 9a and 9b so that the lens 7 is always focused on the reading position 5. Further, the housing 4 is provided with a scan line 4 a in the direction of arrow CD corresponding to the reading position 5.

Next, the operation of the shading correction will be described.

[0007] First, the handy scanner 1 is placed on the white reference document 3, and the start button 4b is depressed. The light source 6 is turned on to irradiate the reading position 5 with light. The reflected light at the reading position 5 converges on the photoelectric conversion element 8 via the lens 7 to be converted into pixels, is converted into a voltage signal as image data by the photoelectric conversion element 8, and is converted by an analog / digital conversion circuit (not shown). Are converted to digital signals and stored in a storage unit (not shown).

Next, the handy scanner 1 is placed on the black reference document 3, and similarly, the black reference image data is converted into a digital signal and stored in the storage unit.

Next, a difference between the stored white reference digital signal and black reference digital signal is obtained and stored in a storage unit.

Next, the original 3 is read and the difference E between the black reference digital signal and the black reference digital signal is calculated. The ratio E / F of the stored difference F between the white reference data and the black reference data is calculated. Based on the correction, illumination unevenness and sensitivity unevenness of the photoelectric conversion element are corrected.

[0011]

In a conventional image reading apparatus, when a shading correction is performed, a white reference original or a black reference original is read, and then the same original is read. And the reading order of the reference document is incorrect.

The reading of the reference document is performed for each device before the image reading device is shipped, and the image reading device is scratched and stained during repeated pressing. A correction value could not be obtained, and the quality of the read image could be degraded.

SUMMARY OF THE INVENTION It is a first object of the present invention to provide an image reading apparatus capable of preventing the same original from being read by mistake and preventing the reference original from being read in an incorrect order. As a second object.

[0014]

In order to achieve the first object, an image reading apparatus according to the present invention comprises: a white reference data storage section for storing white reference document data; and a black reference document data. The reference document identification data is stored by comparing the previously read reference document data with the previously stored reference data, and stores the reference document identification data. The reference document identification data is compared with the identification data of the next read reference document data to identify the reference document data, a switching signal is output, and the previously read reference document data is output. If the reference document data matches the next read reference document data, reference document identification means for outputting an alarm signal, reference document data is input to the input section, and one output section is white reference data. Connected to the black reference data storage unit, and the other output unit is connected to the black reference data storage unit. Comprising switching means for switching the output unit by inputting the switching signal, and a warning means for outputting an alarm by inputting an alarm signal from the reference original identification means.

According to another aspect of the present invention, there is provided an image reading apparatus comprising: a base plate on which a white and black reference original is placed; An image reading device positioning jig comprising a positioning member for positioning the outer peripheral portion of the image reading device on the base plate so as to be deviated to one side from the joint with the reference document.

[0016]

The reference document identifying means of the image reading apparatus constructed as described above discriminates whether the reference document data is white reference data or black reference document data from the read reference document data. The switching means is switched so that the reference original data is white reference data.
If the reference original data is black reference data, it is stored in the black reference data storage unit. At this time, if the previously read reference original data matches the next read reference original data, an alarm is output via the alarm means.

Further, the image reading device positioning jig reads one reference document data and then reads the other reference document data.
Even if the image reading device is turned 180 ° to read the data, the image reading device is positioned at the same position with respect to the reference document.

Therefore, according to the present invention, it is possible to prevent the same reference document from being read by mistake, to prevent the reference document from being read incorrectly, and to prevent the reference document from being scratched or stained.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described with reference to the drawings. Elements common to the drawings are denoted by the same reference numerals.

FIG. 1 is a block diagram showing the basic functions of the present invention. The reference document identification means 10 identifies whether the reference document data is white reference document data or black reference document data from the read reference document data, and switches the switching means 11.
If the reference original data is white reference data, it is stored in the white reference data storage unit 12, and if the reference original data is black reference data, it is stored in the black reference data storage unit 13. Let it. that time,
When the previously read reference document data matches the next read reference document data, an alarm is output via the alarm means 14.

First Embodiment FIG. 2 is an external perspective view showing a first embodiment. The handy scanner 20 is connected to a personal computer 21 via an interface circuit (not shown). The handy scanner 20 is set on an image reading device positioning jig 22 for shading correction.

FIG. 3 is an external perspective view of the positioning jig of the image reading apparatus. FIG. 4 is a sectional view taken along the line EE in FIG. 2. FIG. 5 is an image reading apparatus positioning jig which is obtained by inverting the handy scanner in FIG. It is sectional drawing which shows the state set to the tool.

The image reading device positioning jig 22 includes a base plate 24 on which a reference document 23 is placed, and a positioning member 25 for determining the position of the handy scanner 20 with respect to the reference document 23. The positioning member 25 is provided with a positioning hole 26 into which the outer peripheral portion of the housing of the handy scanner 20 is fitted, and the corners of the positioning member 25 are fixed with screws 27, respectively.

The reference document 23 is composed of a white reference document 23a and a black reference document 23b, and is attached to a base plate 24. A joint 23c between the white reference document 23a and the black reference document 23b extends in the direction of the arrow CD and substantially coincides with the center of the positioning hole 26.

On the other hand, the reading position 5 of the reference original 23 is shown,
The housing 4 of the handy scanner 20 is moved along the arrow CD direction.
Are provided at positions of dimensions F and G (F ≠ G) from opposing outer walls in the direction of arrow B which is the sub-scanning direction.

Accordingly, the reading position 5 of the reference document 23 is shifted from the joint 23c between the white reference document 23a and the black reference document 23b by a dimension H as shown in FIG. (H ≧ 4 mm) FIG. 6 is a block diagram showing a control circuit of the first embodiment.
The input part of the analog image output amplification circuit part 30 is connected to the output part of the line sensor 2, and the output part is the input part of the analog / digital conversion circuit part 31 (hereinafter referred to as A / D conversion circuit part 31). Is connected.

A common terminal (hereinafter referred to as a C terminal) of the switch 32 has a reference voltage terminal + RE of the A / D conversion circuit unit 31.
F is connected, a power supply E and a digital / analog conversion circuit (hereinafter D / A) are connected to a normal close terminal (hereinafter referred to as NC terminal) and a normally open terminal (hereinafter referred to as NO terminal).
An output section of a conversion circuit section 33 is connected.

The reference voltage terminal -REF of the A / D conversion circuit section 31 is connected to the C terminal of the switch 34, and the NC terminal, N
The output terminal of the earth / D / A conversion circuit unit 35 is connected to the O terminal.

The output terminal of the A / D conversion circuit unit 31 is connected to the C terminal of the switch 36, and the input terminal I1 of the comparison circuit unit 37 and the image data processing circuit unit 3 are connected to the NC terminal and NO terminal.
8 inputs are connected.

The input terminal I2 of the comparison circuit unit 37 is connected to the C terminal of the relay 39 as the switching means, and the NC terminal, NO
Input terminals of a black reference data holding unit 40 as a black reference data storage unit and an input unit of a white reference data holding unit 41 as a white reference data storage unit are connected to the terminals.

The input sections of the D / A conversion circuit sections 33 and 35 are connected to the output section of the white reference data holding section 41 and the output section of the black reference data holding section 40, respectively.

A personal computer 21 is connected to the input section I2 of the comparison circuit section 37, which is a component of the reference document identification means.
The reference signal data is input from the input unit I1, and is compared with the reference original data input from the input unit I1, and the output unit outputs the reference original recognition data and the alarm signal to the personal computer 21.

The C terminal of the relay 39 is connected to the comparison circuit 3
7 outputs are connected.

Next, the operation of the first embodiment will be described with reference to FIG. FIG. 7 is a flowchart of the first embodiment.

In step 1, the personal computer 21
Is turned on to set the reference original reading mode. A message "reference document set" is displayed on the display section 21a of the personal computer 21.

In step 2, the image reading device positioning jig 2
Start button 4 of handy scanner 20 set to 2
Press b. It is assumed that the handy scanner 20 is set on the image reading device positioning jig 22 as shown in FIG. The light source 6 is turned on to irradiate the reading position 5 with light.
The reflected light at the reading position 5 passes through the lens 7 to the photoelectric conversion element 8
Are converged into pixels, and are converted into pixels.
As a voltage signal. The voltage signal is amplified by the analog image output amplifying circuit 30, converted into a digital signal by the A / D conversion circuit 31 as reference voltages E to 0 (volt), and output to the comparison circuit 37.

In step 3, the comparison circuit 37 compares the input image data with the reference signal data, and
a or the black reference document 23b is recognized and stored as reference document recognition data. The image data is, for example, a white reference original 23a.
If so, switch relay 39 and proceed to step 4,
If it is the black reference original 23b, the process proceeds to step 8 without switching the relay 39.

In step 4, the white reference original 23a is read and stored in the white reference data holding unit 41.

In step 5, the personal computer 21
Is displayed on the display section 21a of the image reading device, as shown in FIG. Set it in the tool.

In step 6, the start button 4b of the handy scanner 20 is depressed. The light source 6 is turned on to irradiate the reading position 5 with light. The reflected light at the reading position 5 converges on the photoelectric conversion element 8 via the lens 7, is converted into a pixel, and is converted into a pixel.
Is converted into a voltage signal as image data. The voltage signal is amplified by the analog image output amplifier circuit unit 30,
The A / D conversion circuit 31 converts the reference voltage into a digital signal as a reference voltage E to 0 (volt) and outputs the digital signal to the comparison circuit 37.

In step 7, the comparison circuit 37 compares the input image data with the reference signal data, and compares the result with the stored reference document recognition data. Image data
If the data is, for example, a white reference document 23a, a buzzer of the personal computer 21 issues an alarm sound, and a message of "black reference document set" is displayed on the display 21a. Return. This is because the process proceeds to step 6 without reversing the handy scanner 20 in step 5. If the original is the black reference original 23b, the process proceeds to step S8.

In step 8, the black reference original 23b is read and stored in the black reference data holding unit 40. When the reading is completed, the display unit 21a of the personal computer 21
Displays a message of "reference original reading completed".

After the reading of the reference original 23 is completed, if the personal computer 21 is set to the original reading mode,
The switches 32, 34, and 36 are switched, and the reference voltage terminals + REF and -REF of the A / D conversion circuit unit 31 are connected to the white reference data via the D / A conversion circuit units 33 and 35, respectively.
From the black reference data holding unit 41 and the white reference data.
And black reference data are input. The original data is normalized on the basis of the difference between the white reference data and the black reference data, and is processed into image data by the image data processing circuit 38.

In this embodiment, an alarm is issued to a personal computer.
Although the warning sound is output from the buzzer of the printer 21, the handy scanner 20 may be provided with a lamp or the like.

Although the contact type line sensor is used as the reading sensor, a reduction optical system type may be used.

Second Embodiment The second embodiment differs from the first embodiment in the structure of the image reading device positioning jig.

FIG. 9 is an external perspective view showing a positioning jig of the image reading apparatus according to the second embodiment. The image reading device positioning jig 50 includes a base plate 52 on which a reference original 51 is placed,
The positioning member 53 determines the position of the handy scanner 20 with respect to the reference document 51. The positioning member 53 is provided with positioning holes 54 and 55 into which the outer peripheral portion of the housing of the handy scanner 20 is fitted, and the corners of the positioning member 53 are fixed by screws 27 respectively.

The reference original 51 is composed of a white reference original 51a and a black reference original 51b, and is attached to a base plate 52. A seam 51c between the white reference document 51a and the black reference document 51b extends in the direction of the arrow CD and substantially coincides with the center of the base plate 52.

The operation of the second embodiment is the same as that of the first embodiment and will not be described.

The second embodiment is easier to set than the first embodiment because it is not related to the setting direction of the handy scanner 20.

[0051]

Since the present invention is configured as described above, it has the following effects.

From the read reference document data, whether the reference document data is white reference data or black reference document data is identified, the switching means is switched, and the reference document data is changed to white reference data.
If the reference document data is black reference data, it is stored in the white reference data storage unit, and if the reference document data is black reference data, the reference document identification means is stored in the black reference data storage unit. If the reference document data read at the same time matches the reference document data read next, an alarm is output via the alarm means, so that the same reference document is erroneously read, Prevents the reading order of the originals from being incorrect.

The image reading device positioning jig determines the position of the image reading device with respect to the reference document, thereby preventing the reference document from being scratched or stained.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a basic configuration of the present invention.

FIG. 2 is an external perspective view showing the first embodiment.

FIG. 3 is an external perspective view of an image reading device positioning jig.

FIG. 4 is a sectional view taken along the line EE in FIG. 2;

FIG. 5 is a cross-sectional view of the inverted set state.

FIG. 6 is a block diagram showing a control circuit of the first embodiment.

FIG. 7 is a flowchart of the first embodiment.

FIG. 8 is an external perspective view showing an image reading device positioning jig according to a second embodiment.

FIG. 9 is an external perspective view showing a conventional handy scanner.

10 is a sectional view taken along the line AA of FIG. 10;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 20 Handy scanner 2 Line sensor 3 Document 10 Reference document identification means 11 Switching means 12 White reference data storage part 13 Black reference data storage part 14 Alarm means

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-61-256864 (JP, A) JP-A-4-63058 (JP, A) JP-A-61-295762 (JP, A) JP-A-62 157470 (JP, A) JP-A-2-137467 (JP, A) JP-A-2-311083 (JP, A) JP-A-62-125064 (JP, U) JP-A-5-11635 (JP, U) (58) Field surveyed (Int.Cl. ⁷ , DB name) H04N 1/04-1/207

Claims (2)

(57) [Claims] 1. A method for normalizing read data located at an intermediate position based on a difference between white reference document data and black reference document data,
In an image reading apparatus for performing shading correction, a white reference data storage unit for storing white reference original data, a black reference data storage unit for storing black reference original data, The reference document data is compared with pre-stored reference data to store reference document identification data, and the reference document identification data and the next read reference document data are identified. The reference document data is compared with the data to identify the reference document data, a switching signal is output, and when the previously read reference document data matches the next read reference document data, Is a reference document identification means for outputting an alarm signal, and input reference document data to an input section, one output section is connected to the white reference data storage section, and the other output section is the black reference data. Connected to the data storage unit to switch the output unit by inputting a switching signal from the reference document identification unit. An image reading apparatus, comprising: a switching unit for changing an output of the reference document; 2. A base plate on which the white and black reference originals are placed, and a base plate such that the reading position of the image reading device is deviated to one side from the joint between the white reference original and the black reference original. 2. The image reading apparatus according to claim 1, further comprising an image reading apparatus positioning jig including a positioning member for positioning an outer peripheral portion of the image reading apparatus on the image reading apparatus.