JPH0624032B2 - Image inspection equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Outline] In the image inspection apparatus, the present invention divides an inspection object into a plurality of blocks in order to obtain a wide field of view and high resolution,
When the respective blocks are imaged by the image pickup means such as a camera, in order to correct the positional deviation from the camera due to the error in the setting position of the inspection object, a normal image pattern is obtained based on the relative position information between the image pickup means. The quality of the image is determined by collating the captured image data.

[Industrial application field]

The present invention relates to an image inspection apparatus that determines the quality of an image of an inspection target by comparing captured image data with normal image data registered in advance.

In particular, this image inspection apparatus divides an inspection object into a plurality of blocks in order to obtain a wide field of view and high resolution, and divides each block to capture an image.

[Conventional technology]

A conventional image inspection apparatus converts an image pattern of a normal inspection object into relative information with respect to a reference point and pre-registers it in order to absorb an error in a set position of the inspection object, and then registers the inspection object with a camera. Similarly, the image data obtained by image capturing is converted into relative information with respect to the reference point, and the quality of the image of the inspection object is judged by comparing these image patterns with the image data. It was Then, as the reference point, a feature at a predetermined position of the inspection object is used as a mark, and, for example, the corner of the upper left end of the inspection object is detected.

[Problems to be solved by the invention]

However, in such a conventional image inspection apparatus, when the inspection object is large, or when it is a complicated image, in order to obtain high resolution and high field of view, the inspection object is divided into a plurality of blocks. And each block is imaged by the imaging means. Then, since the reference point must be provided for each block, there is a problem that the reference point search processing time increases.

The present invention has been made in view of such a conventional problem, and when the inspection target is a large size or even if the image is complicated, the setting of the reference point marker is performed by the imaging means. It is therefore an object of the present invention to provide an image inspection apparatus capable of performing image inspection at a high speed regardless of the number of the image inspection devices.

[Means for solving problems]

In order to achieve this object, according to the present invention, as shown in the principle block diagram of the present invention in FIG. 1, an inspection target object having a reference point marker is imaged and image data is acquired. A first image pickup means 1 for outputting the image data, another image pickup means 5 for holding the predetermined relative position with the first image pickup means 1 and picking up the image of the inspection object, and outputting image data; And a first storage means 2 for storing the image data output from the other imaging means 1 and 5, and a second storage for previously storing a normal image pattern of the inspection object at a relative address with respect to a reference point. Means 3 and the first storage means 2
The position of the reference point relative to the reference point and the image data at the relative position are detected by detecting the marker of the reference point in the image data output by the first image pickup means 1 stored in Based on the information, the virtual reference point of the image data output by the other image pickup means 5 is obtained, the relative position with respect to the virtual reference point and the image data at the relative position are obtained, and the image data at the obtained relative position are obtained. The collating means 6 for collating the image data at the relative address with the reference point of the image pattern from the second storage means 3 is provided.

[Action]

Next, the operation of the present invention will be described based on the principle block diagram of the present invention shown in FIG.

The first image pickup means 1 picks up an image of an inspection target object having a reference point marker and outputs image data. In addition, another imaging means 5
Holds a predetermined relative position with respect to the first image pickup means 1, picks up the image of the inspection object, and outputs image data. Then, the image data output from the first and other imaging means 1 and 5 is stored in the first storage means 2. Separately from this, a normal image pattern of the inspection object is stored in the second storage means 3 in advance at a relative address with respect to the reference point.

Then, the matching means 6 detects the marker of the reference point in the image data from the first image pickup means 1 stored in the first storage means 2, and detects the relative position with respect to the reference point and the image at the relative position. Data is obtained, and subsequently, a virtual reference point of the image data output by the other imaging means 5 is obtained based on the position information of the reference point, and a relative position with respect to the virtual reference point and image data at the relative position are obtained, The image data at the relative positions respectively obtained and the second storage means 3
And the image data at the relative address of the image pattern from the reference point are compared to determine the quality of the image of the inspection object.

Therefore, a reference point is not necessary in the range imaged by the other image pickup means 5, only a virtual reference point needs to be obtained from the reference point of the first image pickup means 1, the process is easy, and the speed of image inspection is increased. Even if the inspection target is divided into a plurality of blocks in a large or complicated image to be imaged and inspected, the quality judgment is quickly processed.

〔Example〕

 Embodiments of the present invention will be described below with reference to the drawings.

FIG. 2 shows the structure of the image inspection apparatus in one embodiment of the present invention.

Reference numeral 11 is a keyboard corresponding to the inspection object, and a reference position marker is attached at a predetermined position. The keyboard 11 is conveyed to a belt conveyor (not shown) or the like and set at a predetermined position. Reference numerals 12 and 13 denote cameras, which capture images of predetermined blocks on the plane of the keyboard 11 set at the predetermined positions and output image data, respectively. And these camera 12, camera 13
Is fixed in advance so as to always maintain a predetermined relative position. The camera 12 corresponds to the first image pickup means 1 described in the claims, and the camera 13 corresponds to the other image pickup means 5 described in the claims. Reference numeral 14 is a camera switching circuit for switching the cameras 12 and 13 at a predetermined timing. Reference numeral 15 denotes a camera input circuit, which stores the image data output from the camera switching circuit 14 at a predetermined address of a memory 16 formed of a RAM or the like. An image pattern of the normal keyboard 11 is also stored in advance in the memory 16, and the memory 16 corresponds to the first storage means 2 and the second storage means 3 described in the claims. Reference numeral 17 denotes an inspection circuit, which compares and collates a normal image pattern stored in advance in the memory 16 with image data stored from the cameras 12 and 13 via the camera switching circuit 14 and the camera input circuit 15. The quality of the image of the inspection object is judged. The inspection circuit 17 corresponds to the processing means 4 and the matching means 6 described in the claims.
An image bus 18 serves as a path for image data, image pattern information, etc. between the camera input circuit 15, the memory 16 and the inspection circuit 17. Reference numeral 19 denotes a central processing unit composed of a microprocessor or the like, which outputs a control signal to the camera input circuit 15 via the CPU bus 20 and inputs an inspection result from the inspection circuit 17.

Reference numeral 21 is a disk controller, 22 is a floppy disk device, and 23 is a hard magnetic disk device storing various image patterns. When registering a new image pattern, the new image pattern is stored in the floppy disk device 22.
Input from the disk controller 2
It is adapted to be registered in the hard magnetic disk device 23 via the 1. Reference numeral 24 is a display controller, and 25 is a C for displaying image data captured by the cameras 12 and 13.
The RT display device 26 is a keyboard for giving various operation commands. An external input / output control device 27 is composed of an RS232C communication control circuit, a DI / DO control circuit and the like for performing data communication with a host device or the like.

A procedure for pre-storing a normal image pattern of the keyboard 11 at an address relative to the reference point will be described with reference to the drawings.

As shown in FIG. 3, the keyboard 11 is divided into a block B1 imaged by the camera 12 and a block B2 imaged by the camera 13 for image pickup. These blocks B1 and B2 are imaged by the cameras 12 and 13, and the image of the image stored in the memory 16 is stored as image data represented by an address on the horizontal axis and an address on the vertical axis. That is, the image of the keyboard 11 is stored in the memory 16 as image data of 1 or 0 according to the shade of the imprint. G1 is the origin of the block B1 and the address is (0,0). Reference numeral 30 denotes a corner at the upper left end of the keyboard 11 which is preset as a reference point marker. The mark 30 serves as a reference point P1 of the image data included in the block B1. The address of this reference point P1 is (VX, VY). A is a search area when searching for the reference point P1. Reference numeral 28 denotes an arbitrary key top embedded in the keyboard 11. When an image is captured by the camera 12, the image pattern of this key top 28 is stored in the memory 16
However, this image pattern is stored as an address (Mx1, My1) relative to the address (VX, VY) of the reference point 30. The above relationship can be expressed as follows.

Mx1 = Px1-VX My1 = Px1-VY On the other hand, G2 is the origin of the block B2 and the address is (0,0). 31 is a virtual reference point P2 virtually set at the same address (VX, VY) as the reference point 30.
Is. 29 is also an arbitrary key top in the block B2, and when the image is picked up by the camera 13, the image pattern of this key top 29 is the address (Px2, Px2) of the memory 16.
Although located at Py2), this image pattern is stored as an address (Mx2, My2) relative to the address (VX, VY) of the virtual reference point 31. The above relationship can be expressed as follows.

Mx2 = Px2-VX My2 = Py2-VY Such a procedure for registering a normal image pattern in the memory 16 is shown in a flowchart of FIG.

First, in step 51 of FIG. 4, the camera 12 captures an image of the block B1. In step 52, all addresses are searched for whether the reference point 30 exists in the search area A. In step 53, the image data is registered as a normal image pattern in a predetermined address of the memory 16 at a relative address from the searched address P1 (VX, VY) of the reference point 30. Next, in step 54, the camera 13 captures an image of the block B2. In step 55, the address (VX, V
The virtual reference point 31 is virtually set at a position corresponding to Y). Next, the address P2 (VX, V
The image data is stored in the memory 16 at a relative address from Y).
Is registered as a normal image pattern in a predetermined address of.

The operation of the image inspection apparatus having such a configuration will be described with reference to the drawings.

As shown in FIG. 5, the keyboard 11 'having the same structure as the keyboard 11 is conveyed to a belt conveyor or the like and arrives at a predetermined position, and the cameras 12 and 13 are activated. The set keyboard 11 '
Image. The image data of the keyboard 11 'is divided into blocks B1 and B2 and stored in the memory 16. At this time, since the camera 13 holds a predetermined relative position with respect to the camera 12, even if an error occurs in the setting position of the keyboard 11 ', the camera 13 always holds the relative position with respect to the camera 12. There is. G1 and G2 are block B
The origins are 1 and B2, and the addresses are both (0, 0). Reference numeral 30 'is a reference point mark set at the upper left end of the keyboard 11' and serves as a reference point P1 'of the image data of the block B1. The address of this reference point P1 'is (VX', VY '). Search area A is reference point P1 '
This is a search area when searching for. 28 is the keyboard 1
An arbitrary key top embedded in 1 ', and when imaged by the camera 12, the image data of the key top 28 is stored at the address (Px1', Py1 ').
On the other hand, G2 in the block B2 is the origin of the block B2 and is the address (0,0). Reference numeral 31 'is a virtual reference point P2' at the same address as the address (VX ', VY') of the reference point 30 '. 29 is also a key top, and when imaged by the camera 13, the image data of this key top 29 is the address (Px2 ′, Py2 ′).
It is described in. The above relationship can be expressed as follows.

Px1 '= Mx1 + VX' Py1 '= My1 + VY' Px2 '= Mx2 + VX' Py2 '= My2 + VY' Then, a procedure for comparing the stored image data with a normal image pattern to judge the image quality of the keyboard 11 'will be described. It is as shown in the flowchart of FIG.

First, in step 61 of FIG. 6, the camera 12 captures an image of the block B1. In step 62, it is searched whether or not the reference point 30 'exists in the detection area A.
In step 63, the actual image data of the actual image data is obtained by using the detected address P1 '(VX', VY ') of the reference point 30' and the relative address (Mx1, My1) of the already registered normal image pattern. The address (Px1, Py1) is obtained. In step 64, the stored image data is compared with the already registered normal image pattern. Next, in step 65, the block B2 is set by the camera 13.
Image is taken. In step 66, the virtual reference point 31 '
To decide. In step 67, the address P2 '(VX', VY ') of the determined virtual reference point 31' and the relative address (Mx of the normal image pattern already registered are used.
2, My2) is used to find the address (Px2, Py2) of the actual image data. In step 68, the stored image data is compared with the already registered normal image pattern. In step 69, in step 6
If both 4 and the results collated in step 68 are normal, the image of the inspection object is judged to be normal, the judgment result is saved, and the processing of the keyboard 11 'is completed.

Then, when the next keyboard 11 ′ is conveyed to a belt conveyor or the like and arrives at a predetermined position, the camera 1
2 and 13 pick up the image of the set keyboard 11 ', and start the same processing as described above.

In the above-described embodiment, the keyboard is imaged by two cameras, but the block B1 is imaged by one camera, and then the camera is moved so as to maintain a predetermined relative position with respect to the original position of the camera. Then, the block B2 may be imaged by the camera.

〔The invention's effect〕

As described above, according to the present invention, the first image pickup means and the other image pickup means for holding a predetermined relative position are provided, and the collation means 6 determines the relative position information with respect to the first image pickup means. Since the image data from the other image pickup means and the image pattern from the second storage means are collated,
Even if the inspection object is large, or even if it has a complicated image, the reference point can be set in one place regardless of the number of imaging means, so the processing time required to obtain the reference point Therefore, it is possible to provide an image inspection apparatus capable of processing image inspection at high speed.

[Brief description of drawings]

FIG. 1 is a block diagram of the principle of the present invention, FIG. 2 is a block diagram of an image inspection apparatus according to an embodiment of the present invention, and FIG. 3 shows a normal image pattern of the image inspection apparatus shown in FIG. FIG. 4 is a diagram showing a relationship between a captured image and a keyboard when registering,
FIG. 5 is a flow chart when the image inspection device shown in FIG. 2 registers a normal image pattern, and FIG. 5 shows image data captured by the image inspection device shown in FIG. 2 and a keyboard which is an inspection object. FIG. 6 is a flowchart showing the relationship between the normal image pattern registered by the image inspection apparatus shown in FIG. 2 and the image data of the imaged keyboard to check the image quality. DESCRIPTION OF SYMBOLS 1 ... 1st imaging means 2 ... 1st storage means 3 ... 2nd storage means 5 ... Other imaging means 6 ... Collation means

Claims (1)

[Claims] 1. A first image pickup means (1) for picking up an image of an inspection object having a reference point mark and outputting image data, and holding a predetermined relative position with respect to the first image pickup means (1). Along with this, another image pickup means (5) for picking up the image of the inspection object and outputting image data, and a first storage means for storing the image data output from the first and other image pickup means (1 and 5) (2), a second storage unit (3) that stores in advance a normal image pattern of the inspection object at a relative address with respect to a reference point, and the second storage unit (2) stores the first storage unit (2). The marker of the reference point is detected from the image data output by the first image pickup means (1) to obtain the relative position with respect to the reference point and the image data at the relative position, and based on the position information of the reference point. Of the image data output by the other image pickup means (5). A virtual reference point is obtained to obtain a relative position with respect to the virtual reference point and image data at the relative position, and the image data at the obtained relative position and the reference of the image pattern from the second storage means (3) are obtained. An image inspecting apparatus, which is provided with a collating means (6) for collating image data at an address relative to a point.