JPH02237363A - Picture reader - Google Patents

Abstract

PURPOSE:To facilitate the diagnosis relating to focus by diagnosing the focus of a lens and a line sensor based on plural picture data being the result of reading a picture at plural different positions and displaying the result. CONSTITUTION:Plural parallel line sensors 210 read a deciding original picture 212 at plural different positions A, B and C, a parameter reflecting the sharpness of a picture is extracted and it is compared and decided to decide the propriety relating to the focus of a lens 209 and the line sensor 210 and the gradation of the focus and decided and the result is displayed. Thus, the diagnosis relating to the focus is facilitated and when the mount position of the lens 209 or the read sensor 210 is deviated due to mechanical shock or secular change at transportation or installation, the adjustment is simply executed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an image reading device using an image input sensor.

[Prior Art] In order to read a color original image, for example, an R (R)
, G (green), and B (blue) filters are provided in parallel, and a configuration is known in which a reflected light image from a document is color-separated line by line and read and scanned. In an image reading device using an image input sensor such as this, in which multiple line sensors are arranged in parallel, if the light image from the document is not accurately focused and imaged on the line sensor, color shifts and blurring may occur. This may cause other inconveniences.

[Problem to be solved by the invention] In an image reading device that uses a lens to form a document image on a document table onto an image input line sensor and input image data, the positions of the lens and the reading sensor are set at the factory. , is precisely adjusted and focused on the document table.

However, if the mounting position of the lens or reading sensor becomes distorted due to mechanical shock during transportation or installation of the 6J, or due to aging, there has been no easy way to adjust it.

[A Thousand Steps to Solve the Problem] The invention was made in view of the above points, and it is possible to make judgments at multiple different positions in a reading head that images the original image through a lens onto multiple parallel line sensors. A means for reading a document image for use, extracting a parameter reflecting the sharpness of the image, comparing and judging the values, and determining the acceptability and inclination direction of the bin 1-, and displaying the results. By providing this, it is possible to easily diagnose pins 1 through.

[Example] The present invention will be explained below based on Examples.

[First example] [Description of image reading device] FIG. 1 is an explanatory diagram of an image reading device.

Reference numeral 201 is the main body of the image reading device, which includes a document platen glass (
A document 204 held on a mirror pressure plate 200 on a platen 203 (hereinafter referred to as a platen) is irradiated by a lamp 205 . The reflected light image from the original is guided to mirrors 206, 207, and 208,
A 3-line sensor (
The image is formed on the CCD 210 (hereinafter referred to as CCD). CCD21
0 color-separates a color original image, reads it, and sends full-color information to the signal processing unit 211 as red (R), green (G), and blue (B) components. Note that 205 and 206 are mechanically moved at a speed of (1), and 207 and 208 are moved by a motor 250 in a direction perpendicular to the electrical scanning direction of the line sensor at (172) V to scan the entire surface of the document.

212 is a manuscript board on which an image as shown in Fig. 6 is drawn;
It is mounted at almost the same height as the platen 203. The image on the original plate 212 is read by the CCD 210, and a parameter reflecting the sharpness of the image is extracted to diagnose the bin 1 of the CCD 210.

[3 line CCD] FIG. 3 shows the appearance of the 3-line CCD 210.

Reference numeral 301 denotes a red component (R) line, and the surface of a plurality of light receiving elements of the line sensor is covered with a filter that transmits only the red component light. Similarly, 302 is a line sensor for green component (G), and 303 is a line sensor for blue component (B), respectively.
The surfaces of multiple light-receiving elements are covered with filters that transmit only blue component light.

Each line sensor 301 to 303 has a diameter of 180 μm.
The B line sensor is composed of a light receiving element array in which approximately 5000 light receiving elements of 20 μm x 10 μm are arranged, and the R and G sensors have a light receiving element array of 10 μm x 10 71 m. Approximately 5000 elements
It consists of an array of light-receiving elements. The reason why the light receiving areas of the two light receiving elements B, R and G are different is as follows. However, in a filter that only transmits blue component light, the transmittance of blue light is
/Ref F that passes through a transmission filter that transmits only green component light
/Tends to be lower than the transmittance of green light. Therefore,
In order to improve the S/N ratio (signal to noise ratio) of the signal, the light-receiving area of only B is increased, and the signal and level of R and G are made to match.

[Signal Processing Block Diagram] FIG. 2 is a diagram showing the flow of image signals from sensor signals in this embodiment.

The CPU 613 is a CPU that controls the entire neck mounting, and the I/
Predetermined data is set in the motor dryer 620 based on information such as the magnification inputted from the operation unit 622 via the O-boat 6/9, and the motor dryer 620 operates according to the set data according to the desired magnification. A drive signal is sent to the motor 621 (corresponding to the motor 250 shown in the first diagram) to scan the reading system at a desired speed.

In the figure, Hsync is a synchronization signal for main scanning reading,
CLK is an image data transfer clock signal, which is generated at the timing shown in FIG.

In FIG. 2, 601 is an atres counter, and C
CD(R)30 1. CCD (G)302, CCD
(B) Give the read address to 303.

CCD (R) 30 1, CCD (G) 302, CCD
(B) The image read by 303 is converted into an electrical signal, and each intensifier 602, 603, 604 intensifies 1].
The signals are then taken out as digital signals through sample bold circuits 605, 606, 607 and A/D converters 608, 609, 610. 611 and 612 are first-in first-out I memory elements (hereinafter referred to as F I
This is a delay element composed of a 3-line CCD (FO), and is used to adjust the delay between lines of a 3-line CCD according to each reading magnification.

650 is a ROM table, which holds data to be set for each unit according to the magnification.

Specifically, for example, when reading at the same magnification, G
The line sensor 302 of B and the line sensor 303 of B are reading a position corresponding to 18 lines. Therefore, the delay element 612 is set to have a delay of 18 lines by the CPU 613.

ffiJ, there is an interval of 36 lines between the R line sensor 301 and the B line sensor 303, so the delay element 611 has a delay of 36 lines.
Spatial shifts in RGB signals are matched.

For example, when reading at a reduced size of 75%, scanning is performed at 4/3 times the sub-scanning speed of the optical system when it is 100%, so the reading line interval between G and B on the original is 1
This is equivalent to 3.5 lines.

Therefore, since the delay elements 611 and 612 perform correction in units of one line in the main scanning direction, it is necessary to perform data interpolation for 0.5 lines in this case. Interpolation circuit 614, 6
15 performs this data interpolation.

663 to 665 are memories for storing output data of each line sensor 301 to 303, and 660 to 662 are pass switches for switching data storage to each memory 663 to 665.

[Manuscript for judgment] FIG. 6 is an external view of the original plate 212.

This is a view of the document plate 212 viewed from below, and the reading position A.
is located Lmm below the document table 203, and the reading position E.
B is located at the same height as the document table 203, and the reading position w
C is positioned L mm above the document table 203.

[Display message] FIG. 7 is a diagram showing a display message.

Reference numeral 1301 is a device diagnosis switch, which is connected to the operating section 6 in FIG.
It's on 22.

Reference numeral 1302 is a touch panel display located in the operation section 622. If you touch the part labeled "Sensor" with your finger, that part will be highlighted, and if you touch the part labeled "OK" with your finger, 1303 screen will be displayed.

1303, if you touch the part that is displayed as "bint", that part will be highlighted, and if you touch the part that is displayed as OK, the process shown in the process flowchart of FIG. 5 will be executed, and the process shown in FIG. 8 or The message shown in FIG. 9 is displayed on the touch panel display.

[Determination Table] FIG. 10 is a table regarding the determination of the focus position of the R sensor 301, FIG. 11 is the G sensor 302, and FIG. 12 is the B sensor 303.

In the figure: Below the mouth: The focus surface of the sensor is at the bottom of the document table 203. The focus surface of the sensor is near the document table 203. The focus surface of the sensor is at the top of the document table 203. The state × occurs because, for example, in FIG. 10, Sr A>Sr B<Sr C ・-Equation (2
) is the condition. The above condition means that the S value below or above the document table is larger than that near the document table, and does not occur in a state of normal audience. Therefore, Mira 206, 207, 2
08 or some kind of abnormal state may have occurred on the original board 203, which can be determined.

FIG. 8 is a correspondence table between the determination result and the display message when it is possible to determine whether or not 12 noV is possible regarding the direction of the tilt of bin 1.

FIG. 9 is a correspondence table between determination results and display messages when some determination regarding the direction of focus inclination is impossible.

For example, 1 201 in the table: (R-FnGJ1nB
(lower), R lower. The focus surface of the R sensor is below the document table.The focus surface of the G sensor is above the document table.The bin 1 surface of the B sensor is below the document table.

The image reading sensor CCD 210 is a rigid body, and under normal conditions the condition 1201 does not occur and the mirror 20
6, 207, 208 or the document table 212 may be abnormal.

[Processing flow diagram] FIG. 5 is a processing flowchart regarding the CPU 613.

At step 101, the motor 62 is driven to set the reading position at reading position A shown in FIG. Controls the lotus switches 610, 661.6'62 and the image memory 66
3. The image data of the manuscript version 212 is taken into 664 and 665. The sharpness of the image is calculated by calculating the sum of squares of the difference between adjacent pixels (hereinafter referred to as S value) using the calculation 2 for each line stored in the memories 663 to 665, respectively, {X (i) -X (+-1)) The value of the parameter to be reflected. Here, Sr Sg S value at reading position A regarding the AIR signal A-S value at reading position A regarding the G signal Sb S at reading position A regarding the A:B signal
It is a value.

At step 102, the motor 621 is driven, the reading position is set to the reading position wB shown in FIG. 6, and the LS value is calculated. Here, Sr is the S value Sg at the reading position B for the BAR signal Sg is the S value at the reading position B for the BAG signal
Value Sb B: This is the S value at the reading position B related to the B signal.

At step 103, the motor 621 is driven, a reading position is set at reading position C shown in FIG. 6, and the S value is calculated. Here, Sr at reading position C regarding Sr CAR signal
Value Sg S at reading position C regarding COG signal
The value St) is the S value that falls at the reading position C regarding the CAB signal.

Then, at 104, FIGS. 10, 11, and 12
According to the determination table shown in the figure, the focus position is determined after each of the R signal, G signal, and B{;:i.

As mentioned above, the reading position A in Figure 6 is below the document table surface L.
mmO position it, and the reading position wC is above the document table surface. It is located at llIn.

Therefore, for example, Sr
Value Sg B: S at reading position B with respect to R signal
Value Sb S at reading position C regarding CAR signal
Three values of the value or Sr A>Sr B>Sr C --・-Formula (
In case 1), reading position A is located below the document table.
This means that the sharpness of the image on the judgment document plate 212 is most often detected, and the bin 1 surface can be considered to be below the document table.

Then, in step 105, a message is displayed on the operation unit 622 based on the determination table shown in FIG. In Fig. 8, for example, in the case of item number 1111 (nG in R''2nB above), the focus of the R sensor is in the vicinity of the document table, the pin of the sensor is 20 on G near the document table, and the plane is B above the document table. :The bin 1 side of the B sensor is above the document table.

If the distance between the imaging lens 209 and the CCD 210 shown in FIG. 3 is wider than normal, the focal plane will be above the document table 203, and the distance between the imaging lens 209 and the CCD 210 will be narrower than normal. In this case, the focus surface or document platen 2
It will be lower than 03. Therefore, in the case of the condition of item number 1111, it can be considered that the distance between the imaging lens 209 and the lower part of the CCD 210 is wider than the normal state.

As shown in the message column of FIG. 8, the operator can more easily understand the judgment results by displaying them in pictures rather than in text.

[Second Embodiment] FIGS. 13 to 18 are drawings relating to a second embodiment of the present invention.

The first embodiment relates to diagnosis of a reading device using a 3-line parallel color sensor.

The second embodiment relates to diagnosis of a reading device using a red and black two-color reading two-line parallel sensor.

FIG. 13 is an external view of a red and black two-color reading two-line parallel sensor (hereinafter referred to as a two-line sensor) 1401.

It is composed of a black sensor 1402 that inputs the neutral density of the original, and a red sensor 1403 that inputs the red-tinted original image.

FIG. 14 is a signal processing block diagram regarding the second embodiment. In FIG. 14, the same components as in FIG. 2 are designated by the same numbers, and their explanations will be omitted.

FIG. 15 is a processing flowchart regarding the CPU 1601.

The operation will be explained below along the flow shown in FIG.

At step 1501, the motor 1606 is driven to set the reading position of the reading device 201 at reading position A shown in FIG. Thereafter, the bus switches 1602 and 1603 are controlled to capture image data into the image memories 1603 and 1605.

Then, as in the first embodiment, the sum of squares S of the difference between adjacent pixels
are calculated for the black sensor 1402 and the red sensor 1403, and are respectively set as S red 1 AS black 18. 1502
At this point, the motor 1606 is driven to set the reading position 201 at reading position B shown in FIG. Thereafter, the bus switches 1602 and 1603 are controlled to capture image data into the image memories 1603 and 1605. Then, the S value is calculated for the black sensor 1402 and the red sensor 1403 in the same way, and is shifted to S red - B and S black - B, respectively.

At 1503, the motor 1606 is driven to set the reading position of the reading device 201 at the reading position C shown in FIG. Then pass switch 1602.1603
and captures image data into image memories 1603 and 1605.

Then, similarly, the S value is calculated for the black sensor 1402 and the red sensor 1403, and is divided into S red - CS black - C, respectively.

Then, in step 1504, the focus state regarding the red sensor 1403 and the black sensor 1402 is determined based on the determination tables shown in FIGS. 16 and 17.

Then, in step 1505, a corresponding message is selected from the determination result and message correspondence table shown in FIG. 18, and the message is displayed on the operation unit 1607.

FIG. 17 is a focus determination table regarding the red sensor 1403.
Lower red middle red sensor 1403 bin] One side is the document table 203
The focal plane of the upper red/red sensor 1403 means the area above the document table 203.

In addition, FIG. 18 shows a bin determination table regarding the black sensor 14o2.
The focus plane of 2 is below the document table 203 The focus plane of the red medium/black sensor 1402 is near the document table 203 The focus plane of the red and black sensor 1402 is above the document table 203.

FIG. 18 shows a correspondence table between determination results and messages.

The attached figures and the figures in the middle relate to the third embodiment of the present invention.

In the first and second embodiments described above, the judgment manuscript board 21
2 was structured in a step-like manner in the vertical direction as shown in FIG. Also, the image drawn on the judgment manuscript plate 212 is the sixth image.
As shown in the figure, a straight line was drawn perpendicular to the main scanning direction.

In the third embodiment, as shown in FIG. 19, a straight line is drawn on a flat document plate at a constant angle with respect to the main scanning direction.

Further, as shown in FIG. 20, the document table is hung at a certain angle with respect to the horizontal direction of the document table.

By using the oblique image shown in FIG.
It is possible to extract parameters that reflect the resolution of the CD 210 not only in the main scanning direction but also in the sub-scanning direction, making it possible to perform more accurate diagnosis.

Furthermore, by using a flat manuscript board, the manuscript board 212 can be manufactured and removed more easily.

[Effects of the Invention] As explained above, in a reading device that images a document image on a plurality of parallel line sensors through a lens, the document image for judgment is read at a plurality of different positions, and a parameter that reflects the sharpness of the image is set. By extracting and comparing the values, the quality of focus and bin 1 can be determined.
By providing a means for determining the direction of inclination of the image and displaying the result, it becomes possible to easily diagnose the focus.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram of the image reading device of the first embodiment, Fig. 2 is a signal processing block diagram of the first embodiment, Fig. 3 is an external view of the 3-line CCD, and Fig. 4 is the timing of Hsync. 5 is a processing flowchart of the first embodiment, FIG. 6 is an explanatory diagram of the image of the judgment manuscript version 212, FIG. 7 is a diagram showing a display message of the first embodiment, and FIG. FIG. 9 is a diagram showing a relationship table between the determination results and display messages of the first embodiment. FIG. 9 is a diagram showing a relationship table between the determination results and display messages of the first embodiment. FIG. 10 is a diagram showing the relationship between the determination results and display messages of the first embodiment. 11 is a diagram showing a determination table regarding the G sensor 302 of the first embodiment. FIG. 12 is a diagram showing a determination table regarding the B sensor 303 of the first embodiment. , Fig. 13 is an external view of the red-black sensor, Fig. 14 is a signal processing block diagram of the second embodiment, Fig. 15 is a processing flow chart of the second embodiment, and Fig. 16 is a diagram of the second embodiment.
FIG. 17 is a diagram showing a determination table regarding the red sensor 1403 of the second embodiment. FIG. 18 is a determination result and message correspondence table of the second embodiment. FIG. 19 is an explanatory diagram of an image of the judgment manuscript board of the third embodiment, and FIG. 20 is an explanatory diagram of the I-accommodation position of the judgment manuscript board of the third embodiment. , 301-303 phantom CCD. 611.612 is a delay element,
660-662 are lotus switches, 663-665 are dryers, and 613 is a CPU. Now, in front of the can,) Na wa r, Ha ε C

Claims (10)

[Claims] (1) In an image reading device that images a document image through a lens onto an image input sensor composed of a plurality of parallel line sensors, the lens and line An image reading device that performs a diagnosis regarding the focus of a sensor and displays the diagnosis result. (2) An image reading device according to claim (1), characterized in that a diagnosis is made by extracting a parameter value that reflects the sharpness of an image. (3) The image reading device according to claim (2), wherein the value of the parameter reflecting the sharpness of the image is the sum of squares of differences between adjacent pixels. (4) An image reading device according to claim (1), characterized in that the inclination direction of the focus plane is determined by comparing and determining parameter values that reflect the sharpness of the image. (5) An image reading device according to claim (1), characterized in that it reads a judgment document image. (6) The image reading device according to claim (5), wherein the original image for determination is composed of an image having a diagonal component. (7) An image reading device according to claim (5), characterized in that the document image for determination uses a document plate configured in a stepwise manner in the vertical direction. (8) An image reading device according to claim (5), characterized in that the document image for determination uses a document plate having a flat plate attached obliquely in the vertical direction. (9) The image reading device according to claim (1), wherein the plurality of parallel line sensors are three-line color line sensors. (10) The image reading device according to claim (1), wherein the plurality of parallel line sensors are two-line sensors.