JPS58129205A - Method and device for inspecting articles automatically - Google Patents

Abstract

PURPOSE:To inspect articles to be inspected instantaneously without collating with reference picture images by picking up the images of said articles with TV cameras, obtaining the video signals for the focussed images thereof and the out-of-focus images thereof, binary coding both video signals to obtain differences between the same, and erasing the background signals. CONSTITUTION:Level controllers for video signals Ev1 and Ev2 obtained from the 1st TV camera 3 which is focused and the 2nd camera 4 which is out of focus are defined as 7 and 8 in figure. The 1st comparator 11 compares the video signal E'v1 with the 1st threshold level voltage Et1 from a reference voltage generator 12 and outputs the 1st binary coded signal Eb1 which goes to a 1 when said signal is larger than the value thereof and to a 0 when the signal is below said value. The 2nd comparator 13 compares the video signal E'v2 with a threshold voltage Et2 as well and outputs the binary coded signal Eb2. An exclusive-OR circuit 15 takes the difference between these two binary coded signals and outputs the absolute value thereof which goes to a 0 when both Eb1 and Eb2 are 0 or 1. Therefore, the background pulses are erased, and the decision, discrimination, etc. of whether the articles to be inspected are defective or nondefective are made possible by drawing out only the characteristic pulses.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an automatic inspection method and method for inspecting an object for inspecting the outside and inside shape of the object by viewing the object with a telescope camera and processing the video signal. This article relates to automatic inspection equipment that performs.

(绢) As an automatic inspection method that automatically performs product identification while detecting defects in quality products, a television screen camera is used to take an image of the item to be inspected, and 4-circle images are stored in advance. Various comparison methods have been proposed. However, this woodcutter's method requires a very lenient rounding tool to remember me, and it also requires 11IIIa1kg4
The drawback is that the rounding device that requires a calculation device is expensive 6-)
In addition, it takes a long time to compare the -1 of the inspected article with the reference image, which increases the time required for inspection, making it unsuitable for inspection on a production line. In this method, it is necessary to accurately align the reference l#iII and the image of the item to be inspected, and there is a drawback that incorrect inspection may occur if the tie lines used to image the 14 items during inspection on the production line are misaligned. is 629.

The purpose of the present invention is to
It is an object of the present invention to provide an automatic inspection method and #lf for an article which eliminates the above-mentioned drawbacks by making it possible to inspect an article to be inspected only by processing the image gII (No. 1) of the article to be inspected.

In the inspection method of the present invention, the article to be inspected is telescoped.

a step of capturing an image with a camera to obtain a 10th image signal in focus and a 20th out-of-focus image signal; and extracting features from the first image signal. The process of ternarizing and obtaining all the binarized signals including the feature/l las and the background Δ las by comparing the second image value 4# with the 20th threshold level. 11Ilc) The process of obtaining a second binarized signal consisting of a bar ownΔlus of the same width as the background Δlus of the binarized signal, and 11Ilc) The binarized signal and the summary 2 Take the value signal and OII and erase the background Δlus)
1-Characteristics: 1-Characteristics: 1-Characteristics: 1-Characteristics:

Hereinafter, the present invention will be explained with reference to the illustrated embodiment.

FIG. 1 shows seven examples of the positional relationship and the configuration of the optical system when the present invention is implemented using two television sets. A transport device such as teakle, etc., and 2 are objects to be inspected that are placed on top of the transport device 1. 3 and 4 are TV cameras of 41 and 2, and the $10 TV camera 3 is arranged with its lens I 3 m facing the inspected article 2,
The second telepino camera 4 is arranged side by side with the telepino camera 3 of jlEl. A filler 5 is provided between the lens 3a of the first telescope camera 3 and the 16 items 2 to be inspected at an angle of inclination of 45''O, and a portion of the light from the 16 items 2 to be inspected passes through this half mirror. - through dll
The light is incident on the television camera 3 of the camera.

A reflector 6 is disposed in front of the lens 4 of the telepino 1 linker 4 of No. 42, and a portion of the light from the inspected article 2 reflected by the half K is set so that the light is incident on camera 4. Therefore, the first and 742nd television cameras 3 and 4 simultaneously capture images of the inspected article 2 viewed from the same angle.

Then, focus the lens of the first television camera 3 on the object to be inspected 2, and shift the focus of the lens of the 1112O television camera 4 from the object to be inspected. The amount of this focus shift is appropriately set depending on the object to be inspected. In this embodiment, the telepino cameras 3 and 4 are used as the telepino camera of recommendation 1 and 'i42, respectively, but these can also be replaced. As shown in Figure 112, the light from the inspected article reflected by the mirror 5 may be made to directly enter the camera 4 without passing through the reflecting mirror. This figure shows an example of the configuration of an apparatus for carrying out the method of the present invention, in which 7 and 8 are respectively 41 and 2.
Level adjusters 9 and lO adjust the levels of the first and second video signals gv and g,= obtained from the television scene cameras 3 and 4;
These are amplifiers that amplify the 0, 1, and 2 signals. 11 is the first comparator, and this ratio I! The instrument is amplification a
9, the amplifier generates a reference voltage for the 9 ml video signal E4.
2 to (1G) - 9g that is "1" K when the pressure is over Et1
51111fD which becomes "0" when Jl is less than Et1
The second threshold level wax pressure gl= obtained from the binary 4 raw 414 is compared with t, and the second image (No. 1 ffi
,'s X > 142 thread dropper ()E
n1ts When above m, K becomes 1') sE insect is gtt
42 binarized signals Ebs which become rOJ when the value is less than 42 are output.

15 is an Excle-Jig-OR circuit 1g1JlII which takes the difference between the binary signal of 4112) and the binary signal of 71912 and outputs the absolute tll [sound, and the output v0 of this Excl-Jino-Or circuit 15 2 binary signal [
rOJ when bx and g are both “0” or “1”
becomes ``1'' when either 10,000 of b1 or gbs is ``1'' and the other is ``0''. The exclusion OR circuit 415 constitutes an ft#-error erasing circuit.

Next, the inspection method of the present invention using the above-mentioned apparatus l11 will be explained. In this case, first, the object to be inspected 2 is photographed simultaneously with the Pino cameras 3 and 4,
In-focus first video signal 1cyt and out-of-focus first video signal j
Obtain the movie number Evl of l12. In this case, the first and second telephoto cameras 3 and 4 are synchronized with each other. Next, increase the levels of the first and second video signals Icv1 and Ev by fi4Il! 9 and 10 to obtain first and second video signals 1cvI and 1.1 as shown in the gs4 diagram and BK. If there is a defect at approximately the center of the inspected article, this defect appears as a loop-shaped N1Ps approximately at the center of the video signal in FIG. 4A (for example, as shown). Since the 312 telephoto camera 4 blurs the image of the object 2t, the defective part does not clearly appear in the $2 camera, and the focus is 941Ov.
Characteristic parts such as the lumbar sp@ of the A image signal do not appear.

Next, compare 41's Eirin Signal 1evstJ11's Threshold Drepel Eti with Kgl's 2 as shown in Figure 44CK.
Obtained @ conversion signal IJ1t, a12's Eirin (f number Hvs t
The threshold value of J2 is calculated by applying the [Cts] ratio 11 to obtain the binarized signal Ebs of the leg 2 as shown in g4i1D. Here, the threshold level Et1 of dXl is the level for extracting features (To-), and the feature portion to be detected in the first binarized signal (in this case, the missing 11111s
Set it to an appropriate value so that it includes the arm lume that indicates the number of minutes. In this embodiment, the first binarized partial code icb is composed of .
is called a notalus (in this specification, this is a t-feature) indicating the detected spec #i feature aS. ), Pl and Pl
′ should be detected! %*t of the background of the characteristic portion - 6.9 lus (in this specification, this is referred to as background/medium lus).

$2 threshold Js u, IXl binarized signal 1cbt K included background/arms P1' and Pl
Background with the same width and phase as P1 and P; only K
An appropriate value is set so as to form a value signal Ebl with a higher value of 2.

Next, as described above, the first and second binarized atonement symbols I are obtained.
8. By taking the difference between and gbs, the background no! Delete Lus and bring out only Luss PJ in its features. In this embodiment, the exclusive OR circuit 15 takes the absolute value of the difference between the 2 (13) converted signals] 1 cbt and Icbs O, and eliminates the background f and the detected signal consisting of the features P and '. Obtained E0. This PJ appears only when there are 149 detectable parts (defects, if you ask) in the inspected item, so whether or not the inspected item is necessary is determined based on the presence or absence of these nozzles P and 'O. etc. can be done.

Note that the li waveform shown in Fig. 4 is simplified for ease of explanation (6-), and the actual binarization decoding includes many more background pulses, which should be detected. If there are two or more defects, two or more parables may be included.

Thus, in the method of the present invention, the focus is shifted! I created a video signal of 2 and erased this $2 video signal, so I compared it with the reference image. (14) can be inspected using only the video signal of the article to be inspected (14), so there is no need to precisely align the article to be inspected with respect to the television screen camera.

In the above example, two telepino cameras were used, and the focus of the lens of one camera was set to f, but the focus of the lenses of both cameras was set to the object to be inspected, and the focus of the lens of one camera was set to f. It is also possible to obtain a second defocused video signal by shifting the focusing voltage applied to the image pickup tube from the normal voltage. In this case, if an error of one horizontal scan is allowed, the present invention can be implemented with just one television camera as shown below.

$51! il shows the configuration of the device used when implementing the present invention with one telepino camera,
In the same figure, 2o is a telepino 1 camera whose lens is focused on the object to be inspected, 21 and 22 are comparators for 1 and 2, and 23 and 24 are 1 and 1 cameras for sl and sl, respectively.
69, the video signal lcv is compared with 421.
and by 22 it-PtL first and second thread l-
This delay circuit delays by a time corresponding to the t-pressure at the field level. As this delay circuit, any one such as an ultrasonic type, a CCD type, a shift renostar type, a memory type, etc. can be used. 26 is an EXCLE-7f OR circuit, and its first input is delayed by a delay circuit 25 and receives a binary signal gb.
and a binary signal M8b' are input.

In this embodiment, the first and #I2 comparators 21 and 22 constitute a binarization circuit, and the delay circuit 25 and the exclusion OR circuit 26 constitute an error cancellation circuit.

27 is a focused voltage output circuit, in this example, a high voltage voltage fM 2
7 m and poten 7, 1, 1, 27 k and 27, tokarana 9
, the 4xo collecting voltage vl that needs to be applied to the image pickup tube to output the in-focus video signal 1 from the television camera, and the 4xo collecting voltage vl that needs to be applied to the image pickup tube to output the video signal of 9 out of focus 9, and the imaging to the round to output the 2nd video mf1 out of focus. 42 convergence voltage Vl to be applied to the tube. These focusing voltages are applied to the focusing voltage input terminal of the camera 1 of the telepino camera 20 through the switching wA path 28. Kirisada@approximately 2s is a synchronization portion from the video signal E1 through the entire circuit 29, and is pre-loaded by an excellent horizontal synchronizer/dulse PhK! ! Fuku! ! It is controlled by the output of vJAm30. Furimaguf c1ν! The circuit 30 inverts and alternately outputs "l" and "0" signals every time the horizontal synchronization/4 pulse is manually input, and the switching circuit 28 outputs signals of "l" and "0" alternately, for example, when the "l" signal is input @IIC$ A 10-series flux voltage v1 is applied to the image pickup tube, and when a signal of "O" is input manually, a Shutoden electric power fE V * of t42 is applied to the image pickup tube.

The focusing methods of image pickup tubes include electrostatic type, magnetic flux type, and electrostatic/magnetic flux type that uses a combination of both. Focus can be adjusted. Therefore, the television camera used in this embodiment may be of any type, and the magnitude of the rounded second focusing voltage that shifts the focus may vary depending on the object to be inspected. Set to an appropriate 1st shift depending on the part.

(11) Next, an inspection method using the apparatus shown in FIG. 5 will be explained with reference to FIGS. 6A to 6F. Figures 46 and 46 respectively show the horizontal synchronization pulse P and the video signal Ev (output number of the television camera).

As mentioned above, the convergence voltage applied to the convergence voltage input terminal of the image pickup tube of the television camera 20 is switched for each horizontal scan, so the video signal IAvK obtained from the television camera 20 is 1's reflection [1! No. 1cv
m and the focus shift 9 second video signal Evl appear alternately. Therefore, this video signal E7 is converted to a first ratio I11. Blur 2
1, by comparing the rounding value of time extraction with Sren 1-Lepel Et1, we obtain 2 as shown in Figure 6C.
Obtain the digitized signal Wb and further output the signal 1gI No.E. The second comparison 6
22 to the threshold level gt=42, the main binary signal 6 shown in Figure 6 is obtained. The binarized signal is the binarized value number of the 41 Eirin signals g and i. 41 binarized signals in 1 horizontal scan 1111II
The 2111 signal Eb' is a signal containing the 2il conversion value of the second video signal Nvl in one horizontal scan (18). Next, the binary signal 1b1gb signal 11. and the 2Im signal gb/ are input to the exclusive OR circuit 26. As a result, the back volume of the arm p @
'rPs' is deleted to obtain a detection signal containing only the feature 14 PJ. Incidentally, Fig. 116F shows the output signal tube of Furi, f Frojig 41113G.

In the embodiment shown in Figure 1III5, the first and second
Since the signal Nv that alternately includes the ratio #111Kg1 and the second video signal is input, the 2011ized signal Eb has the following:
The video signal gv of KJII2 is compared with the first threshold level Ill and binarized, and in addition to the first binary signal wbs, the video signals g and s of KJII2 are compared with the first threshold level level Ill. 14. It is binarized compared to , and a good signal t is included. Similarly, in the binarized signal, a second binarized signal 1:BS is also included, as well as a video signal g of GT.
Compare vl with the threshold level Itl of s2
The converted signal 1Cbt contains and P′s・9, Eb
, is the background pulse pi・l p,・and the feature pulse P,・
However, depending on the equipment to be tested, the background
It is conceivable that the width of the PIO is equal to the @ of the background Noyals P1 and P■, respectively. In such a case, as shown in FIG. 7, a switching operation is performed every time the horizontal synchronization pulse Pi is input between the teripino camera 20 and the first (182g) comparators 21 and 22. A distribution circuit 31 is provided to perform Jll included in the video signal Ev.
The video (No. 71 g, u and the second video signal z1 may be distributed to the first and second comparators 21 and 22, respectively. In this case, the first ratio [421 output 111 is Comparing the in-focus video signal Ev of #11 with the 1st threshold drepel gtt, only the ll&1 binary signal Eb1 is obtained, and the output side of the g2o specific yield 'a22 is I am happy with the second video signal Nvl which is out of focus.
In comparison with 0 threshold level Icts, only the binary signal Eb of 211 and good/bad is obtained.

In the Queen's Fruit tIIA example, i41 and stripe 2 thread 7 -
When detecting a small defect, it is possible to make the levels of 1 and 42 equal. In this case, as shown in Figure 48, Only a comparator 21 is provided to convert the video signal obtained from the television camera 20 into a digital camera.
What is necessary is to compare it with t.

As described above, according to the method and apparatus of the present invention, an object to be inspected is photographed by a television camera to obtain video signals of an in-focus image and an out-of-focus image, and both video signals and two images are obtained. By converting it into values and taking the difference, the signal t can be obtained regardless of the background of the feature-min.
- Since the image is erased, there is an advantage that inspection can be carried out instantaneously without comparison with a reference image.

Further, since it is not necessary to precisely align the inspected article with respect to the telephoto camera, it is easy to carry out the inspection, and inspection of one article on a production line Km) can be carried out easily and accurately. Furthermore, since Otani's storage device does not require a complicated processing device, the cost of the device can be reduced.

(21)

[Brief explanation of the drawing]

Figures 1 and 2 are explanatory diagrams showing different camera arrangements and optical system configurations when the present invention is implemented using two telephoto cameras, respectively, and Figure 43 is an illustration of the book A professional diagram showing the configuration of the apparatus for carrying out the method, Figure 4 Hitino! I is a diagram showing the signal waveforms of each part in FIG.
FIG. 6 is a diagram showing signal waveforms at various parts of FIGS. 6 to 5. FIG. 2... Article to be inspected, 3.4.20... Television camera, 5... Half mirror 111, 13, 21°2
2... Comparator, 15.26... Exclusio-OR circuit, 25... Delay circuit, 27... Kento voltage output-route, 28... Cut lA1gl pain. (22) Figure 5 Figure 6 (F):

Claims (1)

[Claims] (1) In an automatic inspection method for an article that automatically inspects the appearance and shape of the article to be inspected, the article to be inspected is imaged by a telescope camera and a first video signal in focus is generated. Obtaining the second out-of-focus video signal and comparing the video signal of Kagaki Kiri with the #$1 threshold for feature extraction. Compare the video signals of Tongsu and Kaburahiki 2 with the threshold level of s2 to obtain the first two-wave signal including the characteristic/character representing the characteristic portion and the background/character representing the background of the characteristic portion. The background included in the binarized signal of Aikirei 1 from KotoK is the same as the arm Rus.
To obtain the binarized signal of the second layer consisting of the width-identical tank O background Δrus, and to calculate the background and quantity by taking the difference between the binarized signal of the key and the second binarized signal. A method for automatically inspecting moldy articles with one step: t4# to eliminate mold. (2) Two sets of 41 telepino camera and a second telepino W/camera are provided as a telepino camera, and the first telepino camera obtains the first video signal, and the second telepino camera obtains the first video signal. The method for automatically inspecting an article as set forth in claim 1, wherein the video signal of s2 is obtained using a telepin camera. (3) The telepino camera f: only one is provided,
Claim 1 provides that the first video signal and the Ji2 video signal are obtained alternately by changing the voltage applied to the focusing electrode of the image pickup tube of the scissors telepin camera every horizontal scan. Automatic inspection method for goods. (4) Meal's threshold level is 20. Threshold level is set equally.
Automatic product inspection method. (5) In a self-inspection device that automatically inspects the outside and inside shapes of objects to be inspected, a telescope camera that captures an image of the object to be inspected and outputs a focused 941 video signal. , a telepino camera of aI2 which takes an image of the -1 inspected article and outputs a focus shift 9 No. 20, a lens of the telepino camera of -1 stripes l and -2, and the said inspected article. +sll K fi! , the key is placed so that the light from the item to be inspected is incident on the first television scene camera and the key is incident on the second television scene camera, and the key &! Comparing the video signal of 90 degrees obtained from the 41 telepino camera with the 41 thread w-ruby level, the characteristic part molecule: The 41 mold parable and the background representing the background part, 4 Lus are met.
a first comparator outputting a binary signal of 1;
The video signal of J2 obtained from the TV zone camera is 42
Comparison of hs2 to output a binarized signal of s2 consisting of a background pulse with the same width as the background pulse included in the binarized signal of IiI Kirei I compared with the thread level of 7m - And the ratio of mkirei 1 and rei 2 *aO output Confucian number's jacket and 9
The hxaΔ las elimination circuit that erases the quaternary background quantity lus is used, and the first, & jll! An automatic inspection device for articles whose 4I value is to take pictures of the inspected article from hexagonal angles through an optical system that includes a camera. Then, the inspected article has a len<0
The focused TV zone camera and the focused TV zone camera output the focused video signal from the focused TV zone camera. In the 9th episode, output the out-of-focus stripe 3 image #I compensation code from the 10th collection of Tokyo Voltage and the TV scene camera.
A focused voltage output circuit that outputs a focused voltage of 6JI2 to the recording tube, and a horizontal synchronization signal separated from the output of the telepino camera as input to each horizontal synchronization/ll.
Every KM&! A focusing voltage switching circuit that switches between the 10th focusing voltage and the 20th focusing voltage and applies it to the camera tube, A 102-valued signal including a characteristic pulse representing a characteristic pulse and a background/gurus representing the background of the #characteristic portion is generated, and the f12o video signal is binarized to generate a background included in the l-th binarized i number. A binarization circuit that generates a background pulse with the same width and the same phase as the pulse, and a background nodules that eliminates the background pulse by taking the difference between the binarized signal of cocoon weight l11 and the binarized signal of 42. (7) ELLT, binarization 1J1JlI is a comparison of the output signal of the key telepino camera with the threshold level. The background of 111's 9th erasure is compared to the above! -, the output of - is delayed for a time equivalent to one horizontal scan, and the outputs of the bjI extension m path, the output of the ibengo U path, and the output of the ratio aS are input. From the OR circuit to fk5, 411 claims are made @1Ki6 is Kizhen's automatic inspection device for goods. (s) In the binary conversion circuit, the output signal of the TV screen camera is compared with the ill's shield level, and the output signal is compared with the second shield level. Broom 20 ratio *a and karana p, -ki background・
The arm erase circuit delays the output of the 41st and xojt*tao by the time required for one horizontal scan. (1) An automatic inspection device for articles as set forth in claim 6, which comprises an eta crucito or circuit that interdigitates the output of the other side of the hot water and the output of the i*ffi circuit. (9) The binarization circuit includes a first comparison amount that compares the input signal with the threshold level of III, a comparator of a12 that compares the input signal with the threshold level of ls2, and * The first video signal and the 20 video signal that alternately appear in the output signal of the digital camera are respectively compared to the first ratio I! and a distribution circuit for distributing the signal to a s20 ratio of 12m), and a pulse canceling circuit for delaying the output of one of the first and 11120 filters for a time equivalent to a horizontal scan. Claim 1 comprising: a circuit; and an exclusive or circuit which receives as input the other output of the first and 20th comparison circuits and the output of the #Kiyutsukabetsuro! Automatic inspection equipment for articles listed in I No. 6 JJK Journal.