JPS631245A - Automatic picture checking device - Google Patents

Abstract

PURPOSE:To detect the optiacl density of a pattern to be checked when a check subject obtained by changing a chart for check in response to the checking item is put on a mounting stage, by providing a check pattern position memory means which stores previously the positon of the check pattern existing on the check subject. CONSTITUTION:A pattern information memory means 74 stroes the check subject pattern in a check and processing procedure memory means 75 stores the check processing procedure for the check pattern. A measurement control menas 73 sends a chart code 84 to the means 74 and the means 74 outputs a pattern code 86 showing the check pattern included in a chart shown by the code 84 and a key point position 87 showing the key positoin of the pattern to be checked. The measurement means 76 moves up to the position 87 indicated by the means 73 and detects the picture density to be measured accroding to a picture density detecting format 88.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an automatic image inspection device for inspecting the quality of images reproduced by, for example, a facsimile machine, a printing machine, or a copying machine.

"Prior Art" In offices, various information devices output graphic information such as text and images. A typical example of this is a copying machine that copies original documents. A copying machine forms an electrostatic latent image on a photosensitive drum, reads image information using an image sensor such as a CCD, and develops the image using a developing device, or uses a recording head such as a thermal head. Images are reproduced on paper.

When designing such information devices or shipping these information devices from factories, reproduced images are inspected. There are two types of such tests:

(i) Inspection of whether the information equipment operates normally according to predetermined procedures and reproduces images.

(11) Inspection of whether the quality of the reproduced image is acceptable in the market or within the specifications established at the time of equipment design.

For example, in the case of a copying machine, the inspection items include the position of the image relative to the copied paper, the density of the image relative to the original, and the resolution. The inspector inspects using scales, magnifying lenses, measuring instruments, or visually to check whether each process of the copying machine is working properly and that there are no errors in image reading or toner image transfer position. Determine whether or not.

In the case of copying machines, the latter inspection is also performed by an inspector. That is, the quality of the image is determined by the inspector directly comparing the image copied on the paper with the sample.

In conventional inspections as described above, the inspector is the main person, so
There were the following problems.

(i) Measured values or test results changed when different testers were used.

(11) Even for the same tester, the measured values or test results may change due to familiarity with the test or the psychological influence of the test subject tested previously.

(iii) Measured values or test results also changed due to physical or mental fatigue of the examiner.

In order to avoid such drawbacks, an image inspection device that automatically performs inspection has been proposed (Japanese Patent Application Laid-Open No. 1034-1989).
No. 5 and Japanese Patent Application Laid-open No. 10346/1983).

This image inspection apparatus is provided with a table on which an object to be inspected having an image is positioned and placed.

The object to be inspected is set on this table, and the detection section is placed opposite to it. Then, the detection data output from this detection section is supplied to a data processing section, and the position, density, and resolution of the image are digitized based on the detection data.

``Problems to be Solved by the Invention'' However, in this proposed image inspection device, the detection unit sequentially detects several predetermined patterns.
Only standardized tests can be performed. For example, assume that for a certain information device to be inspected, only density inspection is required, and for other information devices, resolution inspection is required at multiple locations of the object to be inspected.The proposed image inspection device In this case, a standardized test is performed on all objects to be inspected, so the former information equipment is subjected to unnecessary tests, wasting inspection time.Furthermore, the latter information equipment has no inspection points. There was a risk that it would be enough.

Of course, the latter inspection can be accomplished by incorporating a program that performs many inspections at many locations on the object to be inspected, but such image inspection equipment can only handle objects that require simple inspection. There is a problem in that the object to be inspected is inspected more inefficiently.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an automatic image inspection apparatus that can freely set inspection contents depending on the object to be inspected.

"Means for Solving the Problem" The present invention includes an inspection pattern position storage means that stores in advance the position of an inspection pattern existing on an object to be inspected held on a mounting table, and a plurality of types of inspection patterns according to inspection items. Inspection pattern selection means for selecting an inspection pattern whose optical density is to be measured from among the inspection patterns, and optical density measurement means arranged opposite to the selected inspection pattern according to the storage position of the inspection pattern position storage means. The automatic image inspection apparatus is equipped with a moving means for moving the image. When the object to be inspected, whose inspection chart has been changed according to the inspection item, is placed on the mounting table, the pattern to be inspected is searched for, and the optical density measuring means placed opposite to it finds the pattern to be inspected. Optical density is sensed.

Of course, it is possible to set inspection items and omit unnecessary inspections without changing the chart.

"Example" The present invention will be described in detail below with reference to Examples.

Overview of the Apparatus FIG. 1 shows the appearance of an automatic image inspection apparatus according to an embodiment of the present invention. This automatic image inspection apparatus is composed of an inspection section 1, a computer section 2, and a printer section 3. Of these, the inspection section 1 is a section that continuously inspects copy paper 4 as an object to be inspected. The inspection section 1 includes a supply tray 5 and a discharge tray 6. When inspecting a copying machine, a desired chart is set in the copying machine, and copy sheets 4 obtained thereby are stacked on a supply tray 5 as shown. The copy sheets 4 are fed one by one into a cylindrical chart holder 8 by a feed roller ruff. The surface of the chart holder 8 is covered with an insulating film, and the copy paper 4 is electrostatically attracted to this surface by a charging operation by an electrostatic charge supply device (not shown). In this state, the image of the copy paper 4 as the object to be inspected is inspected.

will be held.

The copy paper 4 that has been inspected is peeled off from the chart holder 8 by a peeling mechanism that will be described later. The peeled copy sheets 4 are sequentially discharged onto the discharge tray 6.

An operation display panel 9 is arranged in this inspection section 1.
Disposed here are a power switch 11, a movement key 12 used when manually specifying the pattern of the object to be inspected, and a display 13 for displaying concentration data as a measurement result.

The combinator section 2 can be constituted by a commercially available computer, and performs identification of inspection items, processing of data such as concentration data, and various displays. This part includes a keyboard 15 as a manual means and a CRT 16 as a display means.
, a disk drive device 17 for driving a floppy disk, etc., and a CPU (central processing unit) for data processing is installed inside.

The printer section 3 is a section that outputs test results and the like, and in this embodiment a dot printer is used.

FIG. 2 shows an outline of the inspection section of this automatic image inspection apparatus. A shaft 21 for rotating the feed roller 7 of the inspection section 1 receives driving force from a feed roller drive motor 23 via a chain 22. The supply tray 5 is adapted to be given a force to move upward by the excitation of a solenoid (not shown), and at the time of this excitation, the top layer surface of the copy paper 4 as the object to be inspected comes into contact with the feed roller 21. When the feed roller 21 rotates by a predetermined amount in this state, only one sheet of copy paper 4 in the uppermost layer is fed out. Prior to this feeding, the surface of the chart holder 8 is uniformly charged by a charging mechanism (not shown). As a result, the fed-out copy paper 4 is electrostatically attracted to the chart holding section 8. The rotation of the cylindrical chart holder 8 in the circumferential direction (Y-axis direction) is as follows:
Chart holding line drive motor 26 connected to decelerator 25
This is done by the driving force of

In this embodiment, the outer diameter of the chart holder 8 is 162 mm in diameter.
77 mm, the step angle of the chart holding line drive motor 26 is 1.8 degrees, and the reduction ratio of the reducer 25 is 1/256.
And so. As a result, the chart holder drive motor 26 is driven one step, and the surface of the chart holder 8 is moved by 10 μm in the Y-axis direction. Control of the rotational position of the chart holder 8, that is, the position control in the Y-axis direction, is performed using a point detected by a photosensor 28 in a notch 27 provided at the end of the cylinder as a reference point.

A ball screw 32 rotated by an X-axis stepping motor 31 is arranged above the chart holder 8 so that its axis is parallel to the rotation axis of the cylindrical chart holder B8. The Y-axis direction movement hole 34 of the optical head mounting block 33 is threadedly engaged with the ball screw 32. Therefore, when the X-axis stepping moke 31 rotates, it moves in the X-axis direction while being guided by two guide bars 35 and 36 arranged parallel to the ball screw 32.

In this embodiment, the pitch of the ball screw 32 is 5 mm. The step angle of the X-axis stepping motor 31 is set to 0.
With the configuration set at 72 degrees, the optical head mounting block 33 moves by 10 μm in the X-axis direction by l-step driving. There are two glue switches in the X-axis direction.37.38
are arranged to limit the movement range of the optical head mounting block 33.

A density detection section 41, which will be described next, is attached to the optical head attachment block 33. A magnifying eyepiece lens 42 is also attached to the density detection unit 41, and the position of the image captured by the objective lens 43 can be checked during focus adjustment and especially during manual operation.

FIG. 3 shows the optical structure of the optical head.

The concentration detection section 41 includes a tungsten lamp 51 for illumination. The light emitted from the tungsten lamp 51 is converted into i-light by the illumination lens 52, and the chart holder 8
The measurement site 53 is illuminated. The reflected light from the measurement site 53 is collected by an objective lens 43 and split into two directions by a prism 54 equipped with a semi-transparent mirror (beam splitter).

One of the branched lights is reflected by a mirror 55, passes through a measurement field of view adjustment mechanism 56, has its wavelength component corrected by a color correction filter 57, and enters a photomultiplier tube 58. Here, the measurement field of view adjustment mechanism 56 has an aperture plate 59 and a field lens 61 disposed in the optical path.

The aperture plate 59 is a plate provided with a rectangular opening as shown in FIG. In this opening area of 50 μrn×2500 μm, an image of the measurement site on the copy paper is formed with a 5-fold magnification. On the chart, that is, on the copy paper 4 in this example, the long side is 500 μm and the short side is 10 μm.
The light beam reflected from the rectangular area (FIG. 4) passes through this opening and enters the photomultiplier tube 58 described above. The longitudinal direction of the opening of the aperture plate 59 can be set at an arbitrary angle by an aperture plate rotation solenoid 62.

The other light branched by the prism 54 has its traveling direction changed by the roof-shaped prism 64, and forms an erect image on the observation screen 65.

The image of the measurement site 53 thus formed can be enlarged and observed using the magnifying eyepiece 42.

Circuit Configuration of the Device (Principle Configuration of the Device) Before specifically explaining the device, the fundamental configuration of the circuit will be explained.

The following FIG. 5 shows an outline of the circuit configuration of the automatic image inspection apparatus. This device is equipped with external signal input means 72 for instructing desired inspection items. The measurement control means 73 is configured to set the position and type of the pattern to be inspected and the inspection processing procedure according to the inspection item indicated by the external signal input means 72. The pattern information storage means 74 stores the pattern to be inspected within the object to be inspected, and the processing procedure storage means 75 stores the inspection processing procedure for the pattern to be inspected.

The measurement means 76 scans the surface of the object to be inspected under the control of the measurement control means 73 and detects the image density. The arithmetic processing means 78 performs arithmetic processing on the data obtained from the measuring means 76 according to a processing procedure instructed by the measurement control means 73. The test results obtained thereby are outputted by the output means 83. The output means 83 is typically the printer section 3 shown in FIG. 1, but the test results can also be displayed on the CRT screen of the combinator section 2.

The operation of this automatic image inspection device will be explained in more detail. In the automatic image inspection apparatus, the type of the object to be inspected and the inspection items are coded by the external signal manual means 72 during inspection. A chart code 84 for identifying the chart copied to the object to be inspected and an inspection item code 85 representing the inspection item are sent to the measurement control means 73. The measurement control means 73 sends the chart code 84 to the pattern information storage means 74. Pattern information storage means 7
4 is a pattern code 86 representing a pattern to be inspected included in the chart represented by the chart code 84, and a representative point position 8 representing a representative position of this pattern to be inspected.
Outputs 7. Of these, the pattern code 86 is sent to the processing procedure storage means 75 together with the inspection item code 85,
The image density detection format 88 corresponding to the inspection item and pattern to be inspected and the arithmetic processing code 89 representing the arithmetic processing procedure are read into the measurement control means 73.

At this stage, ■ the type of pattern to be inspected required for inspection, ■
Positional information on where the pattern exists on the copy paper, information on (1) an image density detection method for that pattern, and (2) information about a method for calculating and processing the results corresponding to the inspection items are stored in a code in the measurement control means 73. It will be set in a formatted state.

Among these pieces of information, the representative point position 87 representing the coordinates of the position where the pattern exists and the image density detection format 8
8 is sent to measuring means 76.

The measuring means 76 moves to the representative point position 87 instructed by the measurement controlling means 73, and reads the image density detection format 8.
8, the image density to be measured is detected. The detection result is outputted to the arithmetic processing means 78 as a concentration data string 91. At the end of the concentration data string 91, an end signal 9
2 is added to instruct the start of arithmetic processing.

Upon receiving the end signal 92, the arithmetic processing means 78 executes the arithmetic processing code 89 previously supplied from the measurement control means 73.
Based on this, the corresponding calculation processing routine is selected. This arithmetic processing routine is then loaded into the internal arithmetic processing routine memory area. In the arithmetic processing means 78, the density data string 91 described above is stored in a density data string memory area. The arithmetic processing means 78 processes this concentration data string 91 using the routine loaded into the arithmetic processing routine memory area, and outputs the results according to the test items as the test results 9.
3 and is supplied to the output means 83.

The output means 83 will output this content.

The above-described image density detection and density data arithmetic processing operations are sequentially performed for all inspection patterns preset in the measurement control means 73.

The arithmetic processing means 78 not only performs arithmetic processing on each pattern, but also performs statistical processing of the arithmetic processing results corresponding to all set patterns to be inspected. In this way, the desired test results for the object to be tested will be obtained.

(Configuration of External Signal Input Means) Next, the configuration of the external signal input means will be explained using FIG. 6.

The external signal input means 72 includes encoding means 101. The chart salt 102 and test items 103 manually entered by the operator are encoded by this encoding means 101. When the code type discrimination means 104 receives the coded information, it separates it into a cheat code and a test item code. Then, it is output as a chart code 84 and a test item code 85 via the code control unit 105.

(Structure of Pattern Information Storage Means) FIG. 7 shows the structure of the pattern information storage means. The pattern information storage means 74 supplies the chart code 84 to the pattern information storage position retrieval means 107. The pattern information storage position search means 107 searches for the position of the pattern to be inspected, and searches the pattern information storage unit 1.
08 as a pointer 109.

FIG. 8 shows the contents of the pattern information storage section. The pattern information storage unit 108 stores as data the pattern codes of all the objects to be inspected in the corresponding chart and the representative point positions of the patterns represented by these pattern codes, using the chart code as a key. There is. In this figure, for example, for chart code 'xxx', there are three pattern codes a.
1a and 1b are available. This means that pattern code a is added to the chart specified by this chart code XXX''.
This means that two types of patterns specified by , b are displayed, and the coordinates of the three patterns in total are as shown in the representative point position.

Here, the pattern represented by the pattern code a is, for example, the electrophotographic society test chart "No. 1-
Rt975" resolution measurement pattern (not shown). In this test chart, this pattern is placed in the upper left and lower right parts. Also, pattern code b
The pattern represented by is a pattern for density measurement in this electrophotographic society test chart.

In this test chart, various concentration samples are displayed in a row at the bottom, forming a pattern for concentration measurement.

The pattern information output means 110 includes the pattern information storage section 1
08 is read out from the position indicated by the pointer 109 output by the pattern information storage position search means 107. The read content is the pointer 109
These are all pattern codes and their representative point positions for one chart code indicated by . The pattern code 86 and its corresponding combination of representative point positions 87 are sequentially read out under the control of the measurement control means 73 shown in FIG. 5 and sent into the measurement control means 73.

(Configuration of processing procedure storage means) Next, the contents of the processing procedure storage means 75 are shown in FIG.

The processing procedure storage means 75 is supplied with an inspection item code 85 and a pattern code 86. Among these, the inspection item code 85 is detected by the inspection item code detection means 11.
2, and the pattern code 86 is detected by the pattern detection means 113. The detection result of the test item code detection means 112 is outputted as a first pointer 114 to the processing code storage means 115, and the detection result of the pattern detection means 113 is outputted as the second pointer 115 to the processing code storage means 116.

FIG. 1O shows the contents of the processing code storage means. The processing code storage means 116 stores (i) an arithmetic processing code, (11) a pattern code, and (iii) an image density detection code for each inspection item code. The first pointer 114 output from the above-mentioned test item code detection means 112 specifies the test item code for specifying the test item. Then, the second pointer 115 output from the pattern detection means 113 selects the arithmetic processing code in that inspection item code. In the example shown in FIG. 10, the pattern code a″
It can be seen that for the pattern specified by , the image density detection specified by the image density detection code A'' and the calculation process specified by the calculation processing code A'' are performed. The code contents specified by the two pointers 114 and 115 are:
It is temporarily stored in a storage area within the processing code storage means 116.

Returning to FIG. 9, the explanation will be continued. Inspection procedure search means 11
7 reads out the image density detection code 118 stored in the processing code storage means 116.

In the example of FIG. 10 described above, the image density detection code 118
is “i”. Based on this, the third pointer 119 as address information is stored in the inspection procedure storage means 121.
Output for.

FIG. 11 shows the contents of the inspection procedure storage means. The inspection procedure storage means 121 stores image density detection formats for each image density detection code. There are multiple sets of image density detection formats, each of which is stored in block units. The contents of these block units are, for example, (i) measurement start position, (11) direction, (
iii) interval, (iv)! points, (v) slit direction.

Here, (1) the measurement start position is shown as a position as a representative point. As described above, the representative point is indicated by the coordinates that serve as a reference for each pattern, whereas the counter representative point is the difference between the coordinate value of the starting position and the coordinate value of the representative point when scanning the pattern.

The (II) direction is a scanning direction, and there are two types of directions: an X-axis direction and a Y-axis direction. (iii) The interval is the sampling interval for concentration detection, and (iv) The total number of points is the total number of sampled data. (V
) The slit direction refers to the direction of the opening of the aperture plate 59 shown in FIG. In this embodiment, the opening is set parallel to the X-axis or parallel to the Y-axis rotated by 90 degrees.

The third pointer 119 specifies the image density detection code. In the example shown in Figure 11, the image density detection code
is selected. The first code output means 122 reads out the image density detection format 88 selected by the third pointer 119, and the measurement control means 73 shown in FIG.
is supplied to the measuring means 76 under the control of. On the other hand, the second code output means 123 is processed by the processing code storage means 116.
The arithmetic processing code 89 is read out from the arithmetic processing means 78 and similarly supplied to the arithmetic processing means 78 under the control of the measurement control means 73.

(Configuration of measurement means) The following FIG. 12 shows the contents of the measuring means.

The measuring means 75 can be roughly divided into three parts: (1) an image density detection section, (11) a detection aperture control section, and (iii) a moving section. Measurement output terminal 75
Then, based on the image density detection format 88 supplied from the measurement control means 73, the object to be inspected (in this embodiment, the copy paper 4 on which the chart has been copied) is moved, and the image density is detected in a predetermined format. will be carried out.

That is, the image density detection format 88 (see FIG. 11) supplied from the measurement control means 73 is supplied to the data sampling control section 131, and based on the format 88 decoded here, the image density detection section and the detection aperture control section , and the moving part will be controlled accordingly.

By the way, the data sampling control section 131 controls the light receiving means 1 based on the data 133 obtained from the drive control section 132.
The current location of 33 is known. Therefore, the data sampling system full 131 determines the amount by which the light receiving means 133 should be moved by comparing it with the measurement start position obtained from the image density detection format 88. Data 134 regarding the determined movement amount etc. is sent to the drive control section 132.

The drive control unit 132 determines the amount of movement in the X-axis direction and the amount of movement in the Y-axis direction based on the data 134, and outputs an X-axis direction drive signal 135 and a Y-axis direction drive signal 136 with the corresponding number of pulses. x#J direction drive signal 135
is supplied to the X-axis stepping motor 31, and the Y-axis direction drive signal 136 is supplied to the chart holder drive motor 26 (see FIG. 2) which also serves as a stepping motor.

As already explained, the concentration detection section 41 (FIG. 2) is moved in the X-axis direction by the X-axis stepping motor 31.

Further, the drum-shaped chart holder 8 is rotated in the Y-axis direction by the drive of the chart holder drive motor 26, and the light receiving means 133 consisting of the photomultiplier tube 58 and the like is moved to a desired measurement position.

The data sampling control unit 131 then decodes the image density detection direction, sampling interval, total number of sampling points, and slit direction. First, the aperture direction is compared with the current aperture direction, and an angle signal 138 representing the comparison result with the designated angle is output. Angle signal 138
is supplied to an angle signal generator 139. Angle signal generator 139 supplies control signal 141 to aperture plate rotation solenoid 62 (see FIG. 3) to rotate aperture plate 61 by a desired angle.

When the setting of the light receiving means 133 is completed as described above,
The data sampling control section 131 sets the total number of points obtained from the image density detection format 88 in a counter (not shown) within the control section. Then, the image density detection direction and the sampling interval are outputted to the drive control section 132 as data 134, and theft is performed.

The drive control section 132 moves the concentration detection section 41 or the chart holding section 8 by a predetermined amount in accordance with the instructed detection direction.

By the way, the detection output 14 output from the light receiving means 133
3 is amplified by an amplifier 144 in the image density detection section, and its output 145 is logarithmically converted by a logarithmic converter 146. Conversion output 147 is provided to A/D converter 148. A/D
4. The converter 148 specifies the time at which the A/D conversion is performed from the A/D signal generation R149. /D signal 151 is supplied. The A/D signal generator 149 generates the A/D signal 151 by the A/D start signal 152 supplied from the sampling controller 131.
However, is the Δ/D start signal 152 based on data sampling? The output of a counter (not shown) in 1131 is used.

That is, this counter is preset with a count value corresponding to the measurement start position, and the light receiving means 1
As 33 begins to move, the count increases. When the count value of the counter reaches the preset value, the A/D
A start signal 152 will be output. When the A/D conversion is completed, the A/D signal generation section 149 completion signal 153
Output. When the data sampling control section 131 receives the end signal 153, it manages the above-mentioned counter and instructs the drive control section 132 to move the light receiving means 133, and if necessary, starts the next A/D at a predetermined timing. A D start signal 152 will be output. In this way,
It becomes possible to manage the sampling interval of concentration data.

On the other hand, when A/D conversion is instructed by the A/D signal 151, the Δ/D converter 148 converts the conversion output 147 from analog to digital. The density data 154 after conversion is
The images are sequentially stored in the image density buffer 155. The stored concentration data 154 is supplied to the arithmetic processing means 78 as a concentration data string 91, and is subjected to arithmetic processing.

Now, when the sampling of the concentration data progresses and the built-in counter counts a certain value as the final value, the data sampling control section 131 outputs an end signal 156 to the measurement control means 73.

When the measurement control means 73 receives this end signal 156,
Data regarding the next block is supplied to the data sampling control section 131 as an image density detection format 88. In this way, concentration data is collected for each part to be measured.

(W4Ii of arithmetic processing means) FIG. 13 shows the configuration of the arithmetic processing means. The calculation processing means includes a calculation control section 161. The calculation control section 161 receives the calculation processing code 8 from the measurement control means.
9 is supplied. The arithmetic processing code 89 is a code representing the arithmetic processing procedure. The arithmetic control unit 161 decodes the arithmetic processing code 89 and supplies the result as an arithmetic processing code 162 to the arithmetic processing address search means 163.

The arithmetic processing address search means 163 uses this arithmetic processing code 162 to search the arithmetic processing storage section 164.

The arithmetic processing storage unit 164 stores arithmetic processing data groups necessary for various tests. When the arithmetic processing address search means 163 moves the pointer 165 to the start address of the corresponding memory area by searching, the arithmetic processing address search means 163
A termination signal 166 is sent to 61. After receiving the end signal 166, the arithmetic control unit 161 generates a start signal 167,
Supply to loader starter 168.

When loader stark 168 receives activation signal 167, it generates load signal 169.171.

(1) Pointer 1 in the arithmetic processing storage unit 164
A series of arithmetic processing contents 172 shown in 65 and (ii)
The density data string 91 stored in the image density buffer 155 (see FIG. 12) of the measuring means is transferred to the working area 1.
74. After loading, loader scooter 1
68 supplies a start signal 175 to the working area 174, activates it, and transfers control to the working area 174 itself.

Along with this, the working area 174 contains the concentration data string 91.
The desired arithmetic processing is performed on the data. The result is stored in the calculation result output buzzer 177 as the calculation result 176. The output means 83 shown in FIG. 5 manually outputs this stored content as an inspection result 93 and visualizes it.

Flow of density inspection operation FIG. 14 shows the flow of inspection operation by this automatic image inspection apparatus. The part surrounded by a broken line 181 in this flowchart is a part where pattern information for the corresponding chart is obtained from an externally inputted chart code and read into the main storage section (not shown) in the measurement control means 73 described above.

First, when the automatic image inspection device is started, a message is displayed on the screen of the CRT 16 of the computer section 2 shown in FIG. In step (2), the inspection operator manually inputting the chart code CC from the keyboard 15 is awaited. The chart code is manually created,
When this is read, in step (3), the CPU (not shown) in the measurement control means drives the disk drive device 17 to obtain pattern information about the corresponding chart, and the chart information stored on the floppy disk. Open the file (step ■).

FIG. 15 shows the contents of the chart information file. The chart information file is composed of an index table and a pattern information storage section. In the index table, a chart code CC8 and a pattern information storage address ADPI are stored as a pair. Here, pattern information storage address ADPI
refers to the address of the corresponding pattern information in the pattern information storage unit. For example, if the chart code representing the chart to be inspected is CC1, the pattern information storage address is A D P + . Therefore, the address A D P of the pattern information storage section
Looking at the + part, this chart code has four pattern codes P C, , PC92, P C,3, P
It can be seen that it contains C. And - as an example, the pattern code PC, represented by □, has three coordinates (X, , Y, , ), (X, 2.' Yl2
>, (X, 3. Yl) (7) Sot1. It can be seen that it exists in the position (near).

First, the index table is read into the work area of the main origin tα section (step ■), and the corresponding pattern information storage address ADPI'h is obtained using the manually entered chart code CC as a search element (step ■).
. Next, the address ADP+ of the pattern information storage unit
A series of pattern information starting from is read out and loaded into the pattern information table in the main memory (step ■).
.

FIG. 16 shows an example of the contents of the pattern information table. The pattern information table shows each pattern code for the chart to be measured and the positions of representative points where these exist. For example, in this example, there are two patterns represented by pattern code PC on the same chart, so their representative point positions (Xll, Yll), (X+2. YI2
') are shown on the table.

After the pattern information table for the chart to be inspected is created as described above, the chart information file on the floppy disk is closed (step 2).

The part surrounded by a broken line 182 is a part where a processing procedure is determined from the test item code entered by an external person and the above-mentioned pattern information, and a measurement control table is created in the main memory. The operation of this part will be explained next.

If the chart type is manually set in the previous work, CRT 1
A message requesting that the inspection item be entered manually using a code is displayed on the screen of 6 (step ■), and the operator waits for the inspection operator to input the inspection item code INS+ from the keyboard 15. Inspection item code INS, melt,
For example, it is a code for specifying inspection items such as resolution and density.

If there is only one type of inspection item, the inspection item code INS,
There is only one type of test item, but if there are multiple test items, multiple test item codes rNs1 must be input. Then, enter one test item code l from the keyboard 15.
After reading N5H (step ■), if the request end message is not manually input (step ■; N), reading of other test item codes 1N5H can be repeated.

When the manual operation of inspection item code lN5z is completed, the CPU
In order to ask for processing procedure information for the corresponding inspection item, the first step is to operate the disk drive device 17 and open the processing procedure information file stored on the floppy disk (step 0).

FIG. 17 shows the contents of the information processing procedure file.

The information processing procedure file is composed of a processing procedure code table and a density detection format storage section. The processing procedure code table includes (1) inspection items, (ii)
Four types of information are stored as a set: () pattern code, (iii) arithmetic processing code, and (iv) one-time detection format storage address. Here, the arithmetic processing code cl13 is a code representing the arithmetic processing corresponding to the inspection item code 1nsj, and the pattern code 1)CJ is used when inspecting the inspection item indicated by the inspection item code in SJ. This is the code that represents the pattern. Density detection format storage address a
dfj is a code representing a density detection format for testing the corresponding test item in the pattern described above.

In the density detection format storage section, density detection formats mforml are stored starting from the storage address corresponding to each density detection format storage address adf,1.

The CPU first searches on the processing procedure code table for a column having an inspection item code 1ns4 that matches the input inspection item code INS+ (step 2). Next, enter the pattern code 1) Cj and - in the matching column.
Search whether a matching pattern code PCk exists on the pattern information table shown in FIG. 16 (
Step O). If the number of columns in the pattern table is N, the search is repeated up to this number N (step @).

- If it does not match, the pointer J indicating the search column of the processing procedure code table is advanced to the legal instrument, and the above search is repeated (step 0).

If the two match, read out the arithmetic processing code Cβ and the density detection format storage address adf4 from the matching processing procedure code table (Step 0), and read a series of density detection formats (MFORMi) starting from this address. (=mform)) step [phase]).

Next, the representative point positions (X, Y), . . . for the corresponding pattern are read out from the corresponding column of the pattern information table (step ■).
.

The inspection item code lN5z, arithmetic processing code CIg (=cβJ), and representative point position (X,
Y)i and the concentration detection format MFORMi are written to the measurement control table in the main storage (step 0). FIG. 18 shows the structure of this measurement control table.

The above operations are repeated for each manually inputted inspection item code INS+ (step @), and after the measurement control table shown in FIG. 18 is created, the floppy disk file is closed (step @).

Next, in FIG. 14, the area surrounded by a broken line 183 is the area where the density of the measurement area on the copy paper 4 is detected according to the measurement control table, and the area surrounded by the broken line 184 is the measurement control table and the density detection result. This is the part that uses arithmetic processing to obtain results for the inspection items and outputs them to the outside. The image portions surrounded by these broken lines 183 and 184 are repeated one by one for the previous inspection items on the measurement control table, and are repeated for the number of sheets of copy paper 4 manually input prior to the inspection work. That is, if a plurality of copy sheets 4 on which the same chard is copied are set in advance on the supply tray 5 shown in FIG. 1, each of these sheets will be inspected for each inspection item.

Now, the work flow will be explained starting from the part surrounded by the broken line 183.

At the end of step ■, a message is displayed on the screen of the CRT 16 (step @) requesting the number of sheets of paper to be inspected (in this example, copy paper 4 on which the chart has been copied) NS, and the inspection operator keyboard 15
There is a wait for the number of sheets NS to be calculated manually. As described above, the inspection worker normally inputs the number of copy sheets 4 set in the supply tray 5 manually from the keyboard 15.

When the device receives key human power (step ①), the inspection operation begins. First, the pointer (PP) indicating the current work status of the measurement control table shown in FIG. ).

When the copy paper 4 is sent out from the supply tray 5 and is electrostatically attracted to the chart holding section 8 to complete its installation,
The representative point position (X
, Y) pp and concentration detection format M F ORM p
p is read out (step 0), and a density detection subroutine for detecting the density of the pattern to be inspected is called (step [phase]).

When density detection is completed for the corresponding pattern, the arithmetic processing code of the measurement control table is read out (step @). At the same time, an arithmetic processing subroutine with the same name is loaded/run from the floppy disk, and arithmetic processing is started for the concentration detection result in the output storage section (step [phase]).

In this manner, when the arithmetic processing for the target inspection item is completed, the results are sequentially outputted by the printer 3 (step 0). Thereafter, the pointer is advanced to the next column (+1) of the measurement control table shown in FIG. 18 (step Φ).

In this way, density detection, arithmetic processing, and printer output are repeated according to the contents of each blank in this table until the pointer passes over the last column of this measurement control table (step Φ).

When the pointer crosses the last column of this table. The number NS of copy sheets 4 to be inspected is subtracted by 1 (step 0). If the number of sheets NS is 1 or more, it means that the copy paper 4 to be measured still remains in the supply tray 5 (step ①). So in this case,
The copy paper exchange subroutine is called in the copy paper 4 exchange mode. After the next copy paper 4 is loaded into the chart holding section 8, the pointer of the measurement control table is initialized (step 2), and the inspection of the next copy paper is started.

The above measurement operation is repeated, and the number of copies of copy paper 4 is NS.
is subtracted by 1. Step 0) As a result, the number of sheets NS
When becomes 0, the copy paper exchange subroutine is called in the copy paper 4 discharge mode (step @), and after the last copy paper 4 is discharged to the discharge tray 6, the entire operation is completed.

Positioning for Each Measurement Site The flow of measurement has been described above. Next, positioning for each pattern on the copy paper 4 will be described.

In order to measure an image from a copy sheet on which a chart has been copied, the objective lens 43 of the optical head must correctly capture the target measurement site. By the way, if the density detection unit 41 side is unilaterally set to a predetermined coordinate position, the desired position on the copy paper 4 is ±5
An error of about mm occurs. This is due to the following reasons.

(1) Misalignment that occurs when a chart is copied using a copying machine.

In addition to alignment errors (registration misalignment) between the copy paper 4 and the photosensitive drum of the copying machine and magnification setting errors, there are also Contains errors caused by skew (rotation).

(11) Misalignment when setting the chart in the chart holder 8.

This is a deviation that occurs when the copy paper 4 sent out from the supply tray 5 is set in the chart holding unit 8, and is caused by an error in the setting of the supply tray 5 or a misalignment in position alignment when the copy paper 4 is sent out. In this embodiment, the target position can be reached with an accuracy of ±Q, 5 mm. For this purpose, as shown in FIG.
For example, there are position detection patterns 192 to 1 at those three locations.
94 was placed. These position detection patterns 192~
The coordinates of 194 are grasped by the chart type on the automatic image inspection device side. These patterns on the chart 1
The coordinate values from 92 to 194 are called real coordinates, and these are (Xl, Yl, X2, Y2, X3, Y3
).

The device calculates these real coordinate values (Xl, Yl, X2, Y2, X3, Y
y) to scan the surrounding copy paper 4,
By detecting changes in image density, these types of copy paper 4
Detect the position in . The coordinate values of these position detection patterns 192 to 194 on the copy paper 4 are (Xl+V
I S X2+ y2 , X3+V3).

By assembling the relational expressions of both (X, Y) and (x, y), the actual position (xo, YO) corresponding to the coordinates (xo, yo) of the pattern to be measured on the copy paper 4 is This coordinate value (xo
, yo) to cause the density detection unit 41 to reach the target image area.

The position detection pattern does not need to be placed in three places on the copy paper; for example, by placing it in two places,
It is possible to understand the rotation and positional shift of the Further, by arranging more points, it is possible to grasp the elongation of each part of the copy paper 4, and it is possible to further improve the accuracy of reaching the measurement site.

In the embodiment described above, the image density was detected by setting a fine window with a width of 10 μm on the copy paper as the object to be inspected, so the density data is equivalent to that obtained when image inspection is performed with the human eye. can be obtained. Therefore, depending on the data processing, it is possible to obtain test results (calculations of sensory values) as delicate as those obtained by testing with the human eye.

[Effects of the Invention] As described above, according to the present invention, since the supply means for supplying the object to be inspected to the mounting table is provided, it becomes possible to automatically inspect the object to be inspected, such as copy paper.

Furthermore, since it is possible to select an inspection pattern according to the measurement content, efficient inspection becomes possible.

[Brief explanation of drawings]

The drawings are for explaining an automatic image inspection device according to an embodiment of the present invention, of which FIG. 1 is a perspective view of the automatic image inspection device, FIG. 2 is a schematic configuration diagram showing the main parts of the inspection section,
Fig. 3 is an explanatory diagram showing the arrangement of the optical components of the optical head, Fig. 4 is an explanatory diagram showing the size of the measurement unit area on copy paper, and Fig. 5 is the circuit configuration of the automatic image inspection device. 6 is a block diagram showing the structure of the external signal manual means, FIG. 7 is a block diagram showing the structure of the pattern information storage means, and FIG. 8 is an explanatory diagram showing the structure of the pattern information storage section. , FIG. 9 is a block diagram showing the structure of the processing procedure storage means, FIG. 1O is a block diagram showing the structure of the processing code storage means, FIG. 11 is a block diagram showing the structure of the inspection procedure storage means, and FIG. FIG. 13 is a block diagram showing the configuration of the arithmetic processing means, FIG. 14 is a flowchart showing the flow of inspection operations by the automatic image inspection device, and FIG. 15 is the structure of the chart information file. FIG. 16 is an explanatory diagram showing the structure of the pattern information table, FIG. 17 is an explanatory diagram showing the structure of the information processing procedure file, FIG. 18 is an explanatory diagram showing the structure of the measurement control table, and FIG. FIG. 2 is a plan view of a chart showing locations of position detection patterns. ■・・・Inspection section, 2...Computer section, 3...Printer section, 4...Copy paper (object to be inspected), 5...・
・Supply tray, 7...Feed roller, 8...
...Chart holder (mounting table), 15...Keyboard, 16...CRT. 17... Disk drive device, 41...
...Concentration detection section, 43...Objective lens, 51.
... Tungsten lamp, 58 ... Photomultiplier tube, 59 ... Aperture plate, 62 ...
Aperture plate rotating solenoid, 72... External signal manual means, 73... Measurement control means, 74... Pattern information storage means, 75...
...Processing procedure storage means, 76...Measurement means, 78...Calculation processing means, 83...Output means, 191...
Chart, 192-194...Pattern for position detection. Application: Hitotomi Xerox Co., Ltd. Representative, Patent Attorney Ume Yamanouchi Figure 2 Figure 5 (External Imiya No. λ Kagyu Prisoner-72) Figure 7 Figure 8 Figure 9 Figure 11 121 Figure 12 Kui & JL Moxibustion Department〉 (Surveyor & 76) Figure 19 Figure 16 Figure 17 Figure 18

Claims (1)

[Claims] A mounting table for holding an object to be inspected having an image composed of a plurality of types of inspection patterns, a supply means for supplying the object to be inspected to the mounting table, and an optical density measuring means for detecting the optical density of the inspection pattern. The automatic image inspection apparatus includes an inspection pattern position storage means that stores the positions of inspection patterns in advance, and an inspection pattern that selects a pattern to be inspected whose optical density is to be measured from among a plurality of types of inspection patterns according to an inspection item. and a moving means for arranging the optical density measuring means to face the selected pattern to be inspected according to the storage position of the inspection pattern position storage means, and the optical density measuring means is arranged to face the selected pattern to be inspected according to the storage position of the inspection pattern position storage means. An automatic image inspection device characterized by selectively detecting density.