JP2540323B2 - Object inspection device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an object inspection apparatus, and in particular, the presence or absence of an observed object based on a video signal obtained by imaging the observed object with a television camera. It is suitable for application to an object inspection device that observes the state of an observed object such as the presence or absence of defects.

[Outline of Invention]

The present invention is configured to recognize the normal or abnormal state of the observed object at the monitoring point set on the imaging screen by the imaging screen defined based on the video signal of the television camera. In the object inspection device, the position of the monitoring area is corrected based on the correlation between the first and second detection information obtained from the video signals of the master and the observed object by the position shift detection marker set on the imaging screen. By doing so, it is possible to correct the positional deviation of the observed object with high accuracy.

[Conventional technology]

As an inspection device of this type, in a video signal obtained by imaging an observed object with a television camera, the signal level is within a predetermined range based on the signal level of a signal portion corresponding to a predetermined monitoring area. It has been proposed that the presence / absence of an object, the presence / absence of a defect in each part of the object, and the like be recognized by determining whether or not to enter (Japanese Patent Application No. 58-148243).

For example, in the case of inspecting whether or not the mounting work is correctly performed when the assembly process for mounting the key on the board surface of the keyboard is completed by using the inspection device having such a configuration, for example, when a large weight such as a cooler is used. When inspecting whether or not the work is done correctly when the work process of attaching the label to the surface of the housing of the electrical equipment is completed, a standard observed object with a normal appearance (this is used as the master Compare the luminance of the specified monitoring area set on the image pickup screen when the television camera takes an image with the luminance at the corresponding position on the image pickup screen when the observed object to be inspected is imaged By doing so, a method is adopted in which it is determined that the observed object is abnormal if there is a difference between the two.

In the case of a keyboard, if there is a key that is not attached, the brightness in the monitoring area differs from the brightness of the corresponding portion in the master. Can be reliably detected.

In the case of a cooler, if the same label as the master label is not attached at the same position, the brightness in the monitoring area set at the label position is different from the brightness of the master, so be sure to detect the abnormality. You can

[Problems to be solved by the invention]

However, when trying to inspect the abnormality of the object by such a method, if the position of the monitoring area set on the observed object is slightly displaced from the position of the monitoring area set in the master, Since there is a possibility that a correct determination result may not be obtained, if there is a positional shift in the position of the monitoring area set for the observed object, it is necessary to detect and correct it with the highest possible accuracy.

The present invention has been made in consideration of the above points, and uses a relatively simple method to shift the position of the monitoring area set for the observed object with respect to the monitoring area set for the master. The object of the present invention is to propose an object inspection device capable of detecting with high accuracy.

[Means for solving problems]

In order to solve such a problem, in the present invention, a predetermined monitoring point is set on an image pickup screen 5 displayed based on a video signal VD obtained by picking up an image of the observed object 3 with a television camera 13. By comparing the video signal part corresponding to the monitored area 6 with the corresponding video signal part of the master, the observed object 3 in the monitored area 6 can be obtained.
In the object inspection device configured to detect the normality or abnormality of the state, the positional deviation detection markers 7X and 7Y formed of a plurality of linearly arranged pixel markers are set at predetermined display positions on the imaging screen 5. The position shift detection marker setting means (29, 29E) and the display position where each of the plurality of pixel markers is set in the image information of the image pickup screen 5 obtained when the television camera 13 picks up the image of the master. the first detection information forming means (29 for forming the first detection information INF _M based on the image information obtained from the corresponding video signal portion,
SP2 to SP5) and from the video signal portion corresponding to the display position where each of the plurality of pixel markers is set in the image information of the image pickup screen 5 obtained when the observed object 3 is picked up by the television camera 13. second detection information forming means (29, SP6~SP8) which on the basis of the obtained image information forming the second detection information INF _D and a first image corresponding to a plurality of pixels markers of the first detection information By correlating the array of the information INF _{M with} the array of the second image information corresponding to the plurality of pixel markers of the second detection information INF _D , the arrays of the first and second image information are obtained. Position deviation data creating means (29, SP) for creating position deviation data indicating whether or not there is a mismatched section
9), and when the positional shift data indicates that there is a non-matching section, the positional shift correcting means for correcting the relative set position of the monitoring area 6 with respect to the imaging screen 5 so as to correct the positional shift corresponding to the non-matching section. (29, SP14) and so on.

[Action]

A linear positional deviation detection marker set on the imaging screen 5
Detection information about the master and the observed object 3 from the video signal portion corresponding to the plurality of pixel markers forming 7X and 7Y.
Upon detection of the INF _M and INF _D, the detection information INF _M and
INF _D represents the positional deviation in the direction along the extension direction of the linear positional deviation detection markers 7X and 7Y.

Thus, it is possible to detect the positional deviation between the master and the observed object 3 based on whether or not there is a non-matching section in the arrangement of the detection information obtained from the pixel markers, so that the positional deviation can be reliably detected. Can be corrected.

〔Example〕

[1] First Embodiment Hereinafter, with reference to the drawings, an embodiment in which the present invention is applied to an object inspection device for confirming characters on a label attached to a cooler will be described in detail.

(1) Principle of position shift detection In this embodiment, as shown in FIG. 2, the object inspection apparatus has a label 3 formed by arranging predetermined character patterns 4 at predetermined positions on a housing 2 of a cooler 1. Check if it is attached.

Therefore, the image around the label 3 of the cooler 1 is picked up by the television camera, and the image of the label 3 is displayed at a predetermined position on the image pickup screen 5 as shown in FIG.

Thus, each position of the video image projected on the imaging screen 5 can be represented by the XY coordinates set on the imaging screen 5, and the monitoring area 6 is set by designating the position on the XY coordinates. The presence or absence of the character pattern 4 on the label 3 or whether the character pattern 4 is correct or not is confirmed by using the luminance signal corresponding to the video signal portion included in the monitoring area 6 among the video signals obtained from the camera.

Practically, a surveillance marker having a predetermined shape and size is assigned to the surveillance area 6 so that data on a video signal portion corresponding to the surveillance marker can be taken in.

Thus, in the image pickup screen 5 of the cooler 1, the brightness (for example, the average brightness) of the monitoring area 6 on the label 3 as the observed object and the monitoring area 6 on the image pickup screen 5 obtained from the master.
It is determined whether or not the character pattern 4 on the label 3 as the object to be observed is the same as the master character pattern, by comparing the brightness of the master 3 with the brightness of the predetermined value. It is designed to do.

In order to detect whether or not the display position of the label 3 on the imaging screen 5 coincides with the master, the X-direction displacement detection marker 7X and the Y-direction displacement detection marker are displayed on the imaging screen 5.
7Y is provided.

As shown in FIG. 3, the X-direction positional deviation detection marker 7X is a predetermined number of pixel markers 7X ₁ , 7X ₂ ... 7X _i , 7 _i which are sequentially arranged in the X direction on the imaging screen 5 as an example. ₊₁ , 7X _{i + 2} ...
7X _n is formed in a straight line, and when set on the imaging screen 5, the luminance information of the corresponding pixel row can be taken out pixel by pixel.

In addition, the Y-direction position shift detection marker 7Y is similarly set to Y
The pixels are formed in a linear shape so as to correspond to the pixel rows sequentially arranged in the direction, and thus the luminance information of each pixel on the image pickup screen 5 can be designated.

The X-direction and Y-direction positional deviation detection markers 7X and 7Y are
A part of the corner of the label 3 is set so as to be superimposed on the image of the label 3, and thus, from the portion of the markers 7X and 7Y for detecting the displacement in the X and Y directions, which is superimposed on the label 3. For example, it is possible to obtain the pixel information of the logical "1" level indicating the bright luminance and the luminance information of the logical "0" level indicating the dark luminance from the portion not overlapping the label 3. ing.

Thus, the label of the X-direction positional deviation detection marker 7X is displayed while the cooler 1 as the master is being imaged.
When set on 3M, as shown in FIG. 3 (A), the pixel markers 7X _{i + 1 to} 7X _n are overlapped with the label 3M, so that the pixel as shown in FIG. 3 (B) is displayed. It is possible to obtain the detection information INF _M whose logic level switches from “0” to “1” with the marker 7X _{i + 1} as a boundary.

On the other hand, as shown in FIG. 3 (C), when the label 3D made of the observed object is superimposed on the pixel markers 7X _{i + 3 to} 7X _n , the X-direction position shift detection marker 7X is detected. 3 to FIG. 3D, the detection information such that the logic level is switched from “0” to “1” with the pixel marker 7X _{i + 3} as a boundary.
INF _D is obtained.

Thus, the detection information INF _M obtained from the label 3M of the master
And by performing the exclusive-OR operation for example on the basis of the detection information INF _D obtained from the observed object labels 3D, as shown in FIG. 3 E, by obtaining the correlation information COR,
In the center pixel markers 7X _{i + 1} and 7X _{i + 2} , a non-coincidence section DIS occurs, and the coincidence sections ACC1 and ACC
It occurs in 2.

Thus, from the correlation information COR, the 3D label of the observed object can be obtained.
However, it can be known that the position is displaced from the master label 3M in the X direction by the amount of the disagreement section DIS.

Therefore, when the detection data is obtained from the monitoring area 6 for the label 3D as the object to be observed, if the position of the monitoring area 6 is moved as a whole in the X direction by the number of pixels of the disagreement section DIS, it actually becomes a master. Therefore, the detection data can be obtained from the same position as the monitoring area 6 set on the label 3M.

With respect to the Y-direction position shift detection marker 7Y as well, the same correlation information as that described above for the X-direction position shift detection marker 7X (FIG. 3) can be obtained, and thus in the Y direction as well, the label 3D as the observed object is obtained. However, when the label is displaced from the label 3M as the master in the Y direction, this can be corrected.

If this correlation information COR is expressed as a general expression, Becomes In the equation (1), f (i) represents the brightness level obtained from the i-th pixel marker 7X _i on the imaging screen 5 with the label 3M as the master, and g (i) is the label as the observed object. The luminance level obtained from the i-th pixel marker 7X _i for the imaging screen 5 obtained from 3D is shown. Further, ΔX represents the number of pixels in the non-coincidence section DIS (FIG. 3 (E)), and thus the expression (1) is expressed by the luminance level f of the i-th pixel of the X-direction positional deviation detection marker 7X.
For (i), (i +
The luminance level g (i obtained from the ΔX) th pixel marker
+ ΔX) has the largest correlation.

At this time, it is shown that the luminance data having the largest correlation can be obtained from the pixel markers that are displaced by ΔX for all the pixel markers 7X _{1 to} 7X _n of the X-direction displacement detection marker 7X.

Therefore, if the positional deviation amount ΔX that minimizes the equation (1) is obtained, it can be known as the positional deviation amount ΔX with respect to the master of the observed object.

(2) Specific Configuration The object inspection device 11 has a configuration shown in FIG.

That is, the label 3 of the cooler 1 sequentially carried by the conveyor 12 is imaged by the television camera 13, the video signal VD thereof is input to the video data input unit 14 and the timing control unit 15, and the superimposing circuit is also provided. 16
Is supplied to the monitor unit 17 via.

Conveyor controller 21 that drives and controls the conveyor 12
Each time the cooler 1 is positioned at the image pickup position of the television camera 13, the inspection start signal SIG _IN is given to the timing controller 15.

The timing control unit 15 generates a clock signal that is synchronized with the horizontal and vertical synchronizing signals of the video signal VD, counts the clock signal, and samples the sampling pulse at predetermined intervals for the luminance signal of each line of the video signal VD. SM
P1 is applied to the analog / digital conversion circuit 22 of the video data input section 14, and thus the analog / digital conversion circuit
At 22, the video signal VD is converted pixel by pixel into pixel data DP and supplied to the image memory 24 via the switching circuit 23.

The timing control unit 15 gives the write address signal ADW to the image memory 24 based on the sampling pulse SMP1.

The switching circuit 23 has a master-side switching output terminal M and a detection-side switching output terminal D, stores the pixel data DP in the master image memory section 24M of the image memory 24 via the master-side switching output terminal M, or pixel data. The DP is stored in the detected image memory unit 24D according to the write address signal ADW.

In the case of this embodiment, the CPU 25 is the cooler 1 as the master.
When the master image data acquisition command is input by the operator from the operation switch unit 27 via the bus 26 in the state of the master data acquisition mode in which the image is captured by the television camera 13, the bus 26 is switched on. A pixel obtained at the output end of the analog / digital conversion circuit 22 by sending a switching signal SW to the switching circuit 23 by giving a switching command signal to the timing control section 15 via the pixel The data DP is loaded into the master image memory section 24M side via the master side switching output terminal M.

On the other hand, when an inspection mode command signal is input from the operation switch unit 27, the CPU 25 switches the switching circuit 23 to the detection side switching output end D side via the timing control unit 15, and the conveyor controller 21 controls The pixel data DP is detected by controlling the timing control unit 15 by the inspection start signal SIG _IN generated every time the cooler 1 as the observed object is positioned at the image pickup position of the television camera 13. Take it in on the 24D side.

The CPU 25 has a video data input unit 14, a timing control unit 1
5, the monitor unit 17 in response to the operation input of the operation switch unit 27, according to the program stored in the program memory of the ROM28, while using the register of the RAM29 if necessary, the object inspection apparatus 11 By controlling as a whole, the determination process of the label 3 of the cooler 1 as the observation target is executed, and when the determination for one cooler 1 is completed, the CPU 25 conveys the conveyor through the bus 26 and the control signal output unit 30. By outputting the inspection end signal SIG _OUT to the controller 21, the cooler 1 as a new observation target
Is carried to the imaging position of the television camera 13.

RAM29 is the cursor position register 2 as shown in FIG.
9A, a monitoring area preset register 29B, a detection data register 29C, a rating data register 29D, a positional deviation detection marker register 29E, and a positional deviation data register 29F.

The cursor position register 29A sets the monitoring area 6 on the imaging screen 5 displayed on the monitor 17 based on the video signal VD, selects the position, size, and shape of the monitoring area 6, and selects the X direction. And Y direction displacement detection marker
The position of the cursor used when setting 7X and 7Y is remembered moment by moment.

The monitoring area preset register 29B has one label 3
When the operator inputs up to 16 points through the operation switch unit 27, the position of the monitoring area 6 set for the above character pattern is stored.

The detection data register 29C is used when the CPU 25 captures the brightness data of the monitoring area 6 preset in the monitoring area preset register 29B when the cooler 1 to be observed is positioned at the image pickup position of the television camera 13. , Store this detection data.

The rating data register 29D is a cooler 1 as a master.
Is positioned at the image pickup position of the television camera 13, the brightness data of the monitoring area 6 stored in the monitoring area preset register 29B is stored from the master image memory section 24M.

The position shift detection marker register 29E is arranged in the X direction and the Y direction.
When the operator inputs the image positions of the direction displacement detection markers 7X and 7Y by using the operation switch unit 27, the image positions are stored.

The misregistration data register 29F is for misregistration detection stored in the misregistration detection marker register 29E when the cooler 1 as the master or the cooler 1 as the observation target is positioned at the image pickup position of the television camera 13. The luminance data of the markers 7X and 7Y is stored from the detected image memory unit 24D.

Thus, the data stored in the RAM 29 is read by the CPU 25 as necessary when the operator designates the data processing mode to the CPU 25 by the operation switch unit 27, and is necessary in each processing step. Supply data. At the same time, the data in the RAM 29 is supplied to the pattern generator 31 via the bus 26 as needed, and the pattern data DN is sent to the monitor unit via the superimpose circuit 16.
By giving to 17, the currently set cursor,
Monitoring area 6, X-direction and Y-direction positional deviation detection marker 7X
, And 7Y are displayed on the display screen of the monitor unit 17 by superimposing on the image displayed based on the video signal VD. Thus the operator is the monitor
By looking at the pattern displayed on the display screen of 17, it is possible to input an appropriate command signal to the CPU 25 via the operation switch unit 27.

In the above configuration, the CPU 25 executes the inspection process for the label 3D as the observed object according to the processing procedure shown in FIG.

That is, when the processing program is started in step SP1, the CPU 25 waits for the operator to input a master data fetch command from the operation switch unit 27 in the next step SP2.

Here, the operator sets the cooler 1 as a master at the image pickup position of the television camera 13, and then inputs a master data take-in command to the CPU 25 via the operation switch unit 27.

At this time, the CPU 25 shifts to the next step SP3 and controls the timing control unit 15 via the bus 26 to convert the video signal VD about the master obtained from the television camera 13 into the analog / digital conversion circuit 22, Switching circuit
Master image memory unit via the master side switching output terminal 23
Capture as image data for one frame in 24M.

Subsequently, the CPU 25 moves to step SP4 and uses X of the master image data fetched in the master image memory section 24M by using the data of the position shift detection marker register 29E.
The pixel data of the positional and Y-direction positional deviation detection markers 7X and 7Y are stored in the positional deviation data register 29F.

Subsequently, the CPU 25 shifts to step SP5 and uses the data in the monitoring area pull set register 29B to set the master image memory section 24M.
Of the master image data taken in, the brightness data of the monitoring area 6 is taken in the rating data register 29D as the rating reference data, and thus the label 3M as the master
Ends the data acquisition process for.

Subsequently, the CPU 25 executes the inspection processing program. That is, the CPU 25 waits for the arrival of the detection data fetch command in the subsequent step SP6.

Here, the operator causes the cooler 1 as the object to be observed to be successively carried by the conveyor 12 to the image pickup position of the television camera 13 one by one through the operation switch unit 27.

The conveyor controller 21 sends an inspection start signal SIG _IN to the timing control unit 1 when the cooler 1 as an observation target is positioned at the imaging position of the television camera 13.
By sending it to 5, in the next step SP7, the video signal VD for the label 3D of the cooler 1 as the object to be observed (that is, the object to be observed) is detected.
To take in.

Subsequently, the CPU 25 moves to step SP8 and stores the X direction and Y stored in the displacement detection marker register 29E of the RAM 29.
Using the position data of the direction displacement detection markers 7X and 7Y, the X direction and Y direction displacement detection markers 7X and
The pixel data designated by 7Y is read from the detected image memory unit 24D and the position shift data register 29 of the RAM 29 is read.
Capture in F. In this way, the displacement data register 29F contains the X obtained from the cooler 1 as the master and the observed object.
It is possible to obtain a state in which the pixel data of the positional deviation detection markers 7X and 7Y are captured.

Subsequently, in step SP9, the CPU 25 reads the brightness data corresponding to each pixel of the X-direction and Y-direction position shift detection markers 7X and 7Y fetched in the position shift data register 29F, and the formula (1) is described above. In this way, the positional deviations ΔX and ΔY are calculated based on the position data obtained for the master and the observed object.

Thus, the processing step for obtaining the displacement data representing the displacement amount of the observed object of the cooler 1 as the observed object, that is, the label 3D, which is currently imaged by the television camera 13, is completed.

Subsequently, the CPU 25 proceeds to step SP10 to read the monitoring area position data of the monitoring area preset register 29B, and use the positional deviation data stored in the positional deviation data register 29F for the positional deviation amounts ΔX and ΔY. The corrected signal is transferred to the timing control unit 15 via the bus 26 as an address signal for the detected image memory unit 24D. Thus, the brightness data read from the detected image memory section 24D is taken into the detected data register 29C.

After that, the CPU 25 proceeds to step SP11 and compares the luminance data with the luminance information of the master stored in the rating data register 29D to perform the quality determination processing of the product.

The CPU 25 judges whether the judgment result is good or bad at the subsequent step SP12.
At step S6, the process returns to step SP6 while waiting for the defect processing for improving the defect of the label 3 of the cooler 1 currently imaged by the television camera 13.

On the other hand, when it is determined in step SP12 that the CPU 25 is not defective, the CPU 25 immediately proceeds to step SP6 described above.
Return to

Thus, the CPU 25 waits for the next cooler 1 to be observed to be positioned at the imaging position of the television camera 13, and the new cooler 1 to be observed is set to the imaging position of the television camera 13. When the inspection start signal SIG _IN is newly supplied to the timing control unit 15, the data of the displacement detection markers 7X and 7Y for the new observed object is read, the displacement data is created, and the monitoring area is corrected. Then, the luminance data of the corrected monitoring area is taken in and the quality determination process is repeated.

According to the above configuration, when the position of the label 3D of the cooler 1 to be observed is displaced in the X direction or the Y direction with respect to the position of the label 3M of the cooler 1 as the master on the imaging screen, Is detected based on the pixel data obtained from the position shift detection markers 7X and 7Y, the position shift of the label 3D as the observed object with respect to the label 3M can be easily detected.

Thus, by correcting the position of the monitoring area 6 based on the detection result, it is possible to highly accurately determine whether the label 3 is abnormal.

[2] Second Embodiment FIG. 7 shows another embodiment of the present invention, in which the video data input section 14 includes a sample and hold circuit as indicated by the same reference numerals as those in FIG. 41 and an analog / digital conversion circuit 42, and holds the brightness information of the monitoring area 6 (FIG. 1) in the sample hold circuit 41 under the control of the sampling pulses SMP2 and SMP3 sent from the timing controller 15. , RAM29 after converting this into digital data in the analog / digital conversion circuit 42
The evaluation data register 29D or the detection data register 29C of FIG.

As described above, in the case of FIG. 7, the luminance information about the monitoring area 6 set in the monitoring area preset register 29B of the RAM 29 can be taken into the RAM 29 separately from the data of the position shift detection markers 7X and 7Y. This is different from the configuration shown in FIG.

In the configuration of FIG. 7, the CPU 25 executes the inspection processing according to the processing procedure shown in FIG. 8 in which the corresponding parts to those in FIG.

In FIG. 8, compared with the case of FIG. 6, a processing step for correcting the position of the monitoring area 6 is performed during a processing step SP10 for fetching the luminance data of the monitoring area 6 from the processing step SP9 for creating the positional deviation data. The difference is that it is designed to run SP14.

In the processing procedure of FIG. 8, when the CPU 25 captures the master image data in step SP3 and then captures the positional deviation detecting marker data in step SP4, the video signal VD obtained from the television camera 13 is converted into an analog / digital signal It is taken into the master image memory unit 24M via the conversion circuit 22 and the switching circuit 23. At this time, the data taken into the master image memory unit 24M may be the pixel data DP for detecting the positional deviation of the X-direction and Y-direction positional deviation detection markers 7X and 7Y. In this embodiment, the pixel data DP consists of 1-bit digital information, and this 1-bit digital information is taken into the master image memory unit 24M for the entire image pickup screen 5.

Following this, the CPU 25 causes the sample hold circuit 41 to sample and hold the video signal VD when fetching the rating data in step SP5. Here, the video signal VD sampled and held by the sample and hold circuit 41 is analog luminance information of pixels included in the monitoring area 6, and is an analog signal.

Thus, the CPU 25 converts the sample-hold output of the sample-hold circuit 41 through the analog / digital conversion circuit 42 into a predetermined plurality of bits (for example, 5 bits) of data and stores the data in the rating data register 29D.

After that, the CPU 25 converts the video signal VD into the 2-bit pixel data DP in the analog / digital conversion circuit 22 as the displacement detection data from the observed object in step SP7, and then fetches it into the detected image memory section 24D via the switching circuit 23. , In the next step SP8, after the pixel data of the X-direction and Y-direction positional deviation detection markers 7X and 7Y of the data of the detected image memory unit 24D is loaded into the positional deviation data register 29F, the next step SP9 The positional shift amounts ΔX and ΔY are calculated by calculating the correlation with respect to the positional shift data of.

However, in the case of this embodiment, the CPU 25 uses the following step S
In P14, using the positional deviation amounts ΔX and ΔY,
The monitor area position data read from the monitor area preset register 29B is corrected by the positional deviation amounts ΔX and ΔY and sent to the timing controller 15. In this way, the timing control unit 15 uses the X-direction and Y-direction positional deviation detection markers 7X and
The monitoring area 6 is moved to a position that is translated in the X and Y directions by the positional deviation amounts ΔX and ΔY detected by 7Y, and the analog luminance information of each pixel included in the corrected monitoring area 6 is sampled. The hold circuit 41 is caused to sample and hold.

Thus, in the imaging screen 5, when the position of the label 3D as the observed object is displaced as compared with the position of the label 3M as the master, the displacement amount ΔX
After correcting the position of the monitor area 6 by an amount corresponding to ΔY and ΔY, the brightness information is fetched in step SP10.

As a result, the position information obtained from the label 3M as the master and the position information obtained from the label 3D as the observed object are almost the same, so that the error due to the position deviation does not occur in the result of the determination operation in step SP11. You can

According to the above configuration, the effect described above with reference to FIGS. 4 and 6 can be obtained, and in addition to this,
According to the configurations of FIG. 8 and FIG. 8, the analog luminance information fetched for determining the quality of the observed object is the imaging screen 5
Since it is limited to the monitoring area 6 rather than the entire area, the time for fetching the determination data into the RAM 29 can be further shortened, and the inspection time can be shortened as a whole.

[3] Other Embodiments (1) In the above-described embodiment, the X-direction and Y-direction positional deviation detection markers 7X and 7Y that linearly extend in the X-direction and the Y-direction are used as an observed object. Although the position deviation of the label 3D from the label 3M as the master is detected in two directions of the X direction and the Y direction, the extension direction of the position deviation detecting marker and the number thereof can be variously changed. .

For example, as shown in FIG. 9, when a circular object 41M is imaged as a master, when detecting the positional deviation of the observed object 41D with respect to this object 41M, three positional deviation detection markers 42A, 42B, 42C are used. Object 4 at a predetermined position on the circumference
Set diagonally so as to cross the periphery of 1M and 41D.

By doing so, detection information in three directions can be obtained as the positional deviation information, and thus the positional deviation direction and the amount of the observed object 41D can be easily detected.

(2) In the above-described embodiment, an example in which the marker for positional deviation detection that extends linearly is described, but the present invention is not limited to this, and for example, as shown in FIG. 10, a position that extends in an arc shape. The displacement detection marker 49 may be used.

In FIG. 10, reference numeral 45 is an image of a gear, and a monitoring region 47 is set in each tooth tip 46, and the presence or absence of a defect in the tooth tip 46 is detected by this.

In this case, on the peripheral edge of the center hole 47 of the gear 45, three positional deviation detection markers 48A, 48B, 48 are provided so as to face the center O thereof.
C is provided, and these three positional deviation detection markers 48A to
The gear 45 can be positioned at the position of the center O based on the positional deviation information obtained from 48C.

In addition to this, in the state where the gear 45 is positioned at the center O, the arc-shaped positional deviation detection marker 49 can be set so as to sequentially traverse along the row of the tooth tips 46.

According to the configuration of FIG. 10, the arc-shaped positional deviation detection marker
49 is capable of detecting the detection data representing the positions of the adjacent tooth tips 46 sequentially in pixel units, and accordingly, the tooth tip 46 of the gear 45 as the observed object with respect to the tooth position of the gear as the master. If the position is displaced in the rotation direction, the amount of displacement in the rotation direction can be detected.

Therefore, based on the detection output of the arc-shaped positional deviation detection marker 49, if the monitoring area 47 is moved in the rotation direction as a whole so as to eliminate the positional deviation, if there is a missing tooth with respect to the tip of the master, This can be reliably detected without being affected by the positional deviation.

(3) In the above-described embodiment, the position shift detection marker having a width of one pixel is applied, but the position shift detection marker is not limited to this width and may be a width corresponding to a plurality of pixels. Good, the point is that it is linear as a whole.

(4) In the above-described embodiment, as shown in FIG. 3, the observed object displayed in the image pickup screen clearly has the white level or the black level, and is therefore included in the position shift detection marker. An example in which the present invention is applied to the case where the detection information that clearly switches from the logical "0" level to the logical "1" level can be obtained from the pixel to be detected corresponding to the boundary position of the observed object has been described. When the boundary of the observed object on the imaging screen includes a gray level, the boundary position may be unclear.

That is, in this case, as shown in FIG. 11 (A), the video signal VD obtained from the television camera 13 has pixels of distance Δd before falling from the white level L _W to the black level L _B at the boundary position. Therefore, a detection signal whose position deviation amount is unclear is generated by the number of pixels within the distance Δd.

In such a case, in the configuration of FIG. 4, for example, in the luminance data captured in the master image memory unit 24M and the detection image memory unit 24D, the displacement data from the pixel included in the displacement detection marker is detected. White level L _W and black level L _B based on the detection data captured in register 29F
Data is extracted, the threshold level L _TH is calculated as the average value, and the threshold level L _TH is calculated.
By comparing the detection signal representing the video signal VD to _TH, it is sufficient to obtain detection information INF _D of the detection information INF _M and the object to be detected on the master, as shown in FIG. 11 (B).

Thus, it is possible to reliably detect the positional deviation of the detected object including the gray level.

(5) In the above-described embodiment, the present invention is applied to the case of inspecting the label attached to the cooler and the tooth top of the gear, but the present invention is not limited to this and can be applied to various observed objects. .

(6) In the above-described embodiment, when the image of the observed object is displaced from the image of the master, the position of the monitoring area is corrected. However, instead of this, the television camera 13 Alternatively, even if the image pickup screen of the video signal VD is corrected as a whole by changing the relative position of the observed object imaged by the television camera 13, the same effect as the above case can be obtained. be able to.

〔The invention's effect〕

As described above, according to the present invention, a linear positional deviation detection marker is set on the imaging screen, and the correlation of the detection information obtained from the video signal portion corresponding to the pixel marker included in the positional deviation detection marker is used. Therefore, by detecting the positional deviation, the positional deviation on the image of the observed object with respect to the master can be detected and corrected with high accuracy.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing an image pickup screen in the first embodiment,
FIG. 2 is a side view showing a cooler to be observed, FIG. 3 is a signal diagram used for explaining detection information obtained from the positional deviation detecting marker, and FIG. 4 is a diagram showing the object inspection apparatus in the first embodiment. A systematic connection diagram showing a concrete configuration, FIG. 5 is a schematic diagram showing a configuration of RAM, FIG. 6 is a flow chart showing an object inspection processing procedure, and FIG. 7 is a second embodiment of the object inspection apparatus. Fig. 8 is a systematic connection diagram, Fig. 8 is a flow chart showing the object inspection processing procedure, Fig. 9 is a schematic diagram showing the arrangement of position deviation detection markers when the observed object is circular, and Fig. 10 is FIG. 11 is a schematic diagram showing the arrangement of the positional deviation detection markers when the observed object is a gear, and FIG. 11 is a signal waveform diagram for explaining the signal processing when the observed object includes gray levels. 3 ... Label, 4 ... Character pattern, 5 ... Imaging screen,
6 ... Monitoring area, 7X, 7Y ... Positional deviation detection marker, 11
...... Object inspection device, 13 …… Television camera, 14 ……
Video data input section, 15 …… Timing control section, 25 ……
CPU.

Claims (3)

(57) [Claims] 1. A video signal portion corresponding to a monitoring area set at a predetermined monitoring point on an image display screen displayed based on a video signal obtained by imaging an observed object with a television camera. In the object inspection device adapted to detect the normality or abnormality of the state of the observed object in the monitoring area by comparing with the corresponding video signal portion of the master, a plurality of linearly arranged objects are arranged. Positional deviation detection marker setting means for setting a positional deviation detection marker composed of pixel markers at a predetermined display position on the imaging screen, and the imaging screen obtained in a state in which the master is imaged by the television camera Forming the first detection information based on the image information obtained from the video signal portion corresponding to the display position where the plurality of pixel markers are set among the image information Corresponding to a display position in which each of the plurality of pixel markers is set in the image information of the imaging screen obtained in a state in which the observed object is imaged by the television detection camera. Second detection information forming means for forming second detection information on the basis of image information obtained from the video signal portion, and first image information corresponding to the plurality of pixel markers of the first detection information. By obtaining a correlation between the array and the array of the second image information corresponding to the plurality of pixel markers of the second detection information, a section that does not match the array of the first and second image information is obtained. A positional deviation data creating means for creating positional deviation data representing whether or not there is a position deviation data, and when the positional deviation data indicates that there is the non-matching section, the position deviation corresponding to the non-matching section is corrected. As described above, an object inspection apparatus comprising: a positional deviation correcting unit that corrects a relative set position of the monitoring area with respect to the imaging screen. 2. The position shift is corrected by moving the display position of the monitoring area on the imaging screen of the observed object with respect to the observed object based on the position shift detection result. The object inspection device according to claim 1. 3. The position shift is corrected by moving a display position of an imaging screen of the observed object with respect to the monitoring area based on the position shift detection result. Item inspection apparatus according to item 1.