JPS61209305A - Image input apparatus - Google Patents

Abstract

PURPOSE:To make it possible to inexpensively pick up the image of matter to be inspected with high resolving power, by rotating an image pick-up means having a plurality of light receiving elements linearily arranged thereto around the arrangement direction of the light receiving elements. CONSTITUTION:When processed parts are placed on an illumination stand, light is projected to the line sensor of a unidimensional CCD camera 1 and predetermined charge is accumulated at every picture element and successively outputted as voltage quantity by the timing signal of CLOCK 1. This voltage quantity is inputted to an image processing part 11 as binary image data by a comparator 17. Said image data is stored in the processing part 11 and, when this operation is performed N-times, the image data of N picture elements of the line sensor are stored on a matrix in a line to constitute unidimensional image data. At the same time, an electromotive cloud stand 3 is slightly rotated according to the timing signal of CLOCK 2. When the stand 3 is successively rotated within a range of necessary angle of rotation, two-dimensional image data, wherein the picture elements of the line sensor correspond to a lateral direction on the matrix and the angle of rotation of the stand 3 corresponds to a longitudinal direction, is constituted.

Description

Detailed Description of the Invention [Technical Field of the Invention] The present invention relates to an image processing device that performs processing by recognizing, for example, the shape and surface of an object. Regarding equipment.

[Technical background of the invention and its problems] Due to the recent technological development of electronic computers, digital image processing is being widely deployed in the industrial field due to the demand for automation of production processes and inspection processes. Specifically, there are various methods such as defect inspection of IC masks, LSI wiring, shape inspection of processed parts, etc.

In such image processing apparatuses, an image sensor such as a two-dimensional CCD camera has conventionally been often used as an image input device. That is, image data captured by a two-dimensional CCD camera is stored in an image memory, and then image processing is performed.

However, the resolution of this two-dimensional CCD camera is as low as 320 x 480 at the current technological level, and when trying to detect small changes in shape of relatively large parts, such as shape inspection of press-formed parts, etc.
Although high resolution is required, it cannot be used in such cases. In addition, in order to increase the actual resolution, it is necessary to move the camera closer to the object to be inspected or use a long focal length lens, but in this case, the entire object to be inspected can be captured in one image with one camera. I can't grasp it.

In particular, if the object to be examined has a concave shape, it cannot be captured in an image regardless of the resolution. Furthermore, it is conceivable to capture the entire object to be inspected in one image using multiple cameras, but in this case, it is difficult to process the boundary portions of the images of each camera, and it is also expensive. As described above, there are various problems due to the low resolution, the shape of the object to be examined, etc., and as a result, there is a problem that image recognition of the object to be examined cannot be performed reliably.

[Objective of the Invention 1 This invention has been made in view of the above, and its purpose is to image a test object at low cost and with high resolution regardless of the size, shape, etc. of the test object. The purpose of this invention is to provide an image input device that can perform the following tasks.

[Summary of the Invention] In order to achieve the above object, the present invention includes an image carrier having a plurality of light receiving elements arranged in a linear manner, and a rotation means for rotating the imaging means around the arrangement direction of the light receiving elements. The main point is to have the following.

[Embodiments of the invention] Hereinafter, the present invention will be explained in detail using the drawings.

FIG. 1 is a block diagram showing an embodiment in which the present invention is applied to an image processing apparatus. The outline of the configuration in the figure includes a one-dimensional CCD camera 1 that images an object to be inspected, an electric pan head 3 on which the camera is installed and rotates, and a pan head drive section 7 that drives the pan head. an image input section 9, a control section 5 that controls the one-dimensional COD camera 1 and the pan head drive section 7, and an image processing section 11 that processes the image data obtained in the image input section 9. The structure is as follows.

FIG. 2 is a diagram showing a mode in which the image processing apparatus of this embodiment is applied to shape inspection of pressed parts. In the figure, reference numeral 21 is a press-processed part in which a hole is formed, which is an object to be inspected, and reference numeral 23 is a lighting stand. Furthermore, for the sake of explanation, the X direction, Y direction, and Z direction are taken as shown in the figure.

The one-dimensional CCD camera 1 is composed of a line sensor and a wide-angle lens (not shown), and the line sensor is one-dimensional and has pixels in the X direction. The electric pan head 3 is rotated by the pan head driving section 7 as indicated by an arrow 25 in FIG. Specifically, for example, the size of the press-processed part 21 is set to about 600 x 1000.
If it is about mm, the one-dimensional CCD camera 1 is connected to the lighting stand 23.
It is appropriate that the camera be installed at a height of about 500III11 from 2000, the number of pixels of the line sensor should be 2048, the angle of view of the lens should be about 75°, and the rotation angle of the electric pan head 3 should be about 120°.

The control unit 5 includes a clock generator 13 and an N-ary counter 1.
Consists of 5. Clock generator output signal C
LOCK1 has a pulse waveform as shown in FIG. 3(a).

The N-ary counter 15 inputs the signal CLOCK1, counts N pulses as shown in FIG. 3 (ω), generates one pulse, and outputs the signal CLOCK2. Here, N is the number of pixels of the line sensor. In other words, the signal CLOCK1 controls the one-dimensional CCD camera 1, and the signal CLOCK2 controls the pan head motor.

The image processing unit 11 is composed of, for example, a minicomputer, and processes the image data obtained by the image input unit 9.
It also controls the image input section 9 and the image output section (not shown). Note that 17 is a comparator that compares the analog signal obtained by the one-dimensional CCD camera 1 with the reference voltage BASE signal and outputs it to the image processing section 11 as binary image data.

Further, in this embodiment, the control section 5 is an independent component, but it is also possible to configure the CPLIk (central processing unit) in the image processing section 11 to have the function of the control section 5.

First, the operation of the image processing apparatus according to this embodiment will be explained.

First, when the pressed part 21, which is the object to be inspected, is placed on the illumination stand 23, the light that has passed through the hole formed in the part 21 or directly onto the line sensor of the one-dimensional CCD camera 1 is projected, and each A predetermined charge is accumulated in each pixel according to the intensity of light. This charge radiation is sequentially output as, for example, a voltage amount at regular intervals according to a timing signal of CLOCKl.

This voltage amount is determined by the reference voltage BA in the comparator 17.
It is compared with the SE signal and input to the image processing section 11 as binary image data. In the image processing section 11, this binary image data is sequentially stored in a row on a matrix as shown in FIG. 4 in an image memory. When this series of operations is performed N times, the image data of N pixels of the line sensor are stored in one column on the matrix, forming -dimensional image data. At the same time, on the other hand, one-dimensional COD
The electric pan head 3 on which the camera 1 is installed is slightly rotated after the drive control of the pan head drive section 7 according to the timing signal of CLOCK2. In other words, one pulse of the signal CLOCK2 is output for every N pulses of the signal CLOCK1, so one-dimensional image data is generated on the matrix of the image memory for each rotation angle of the electric pan head controlled by the signal CLOCK2. They are constructed in sequence. When the electric pan head 3 is sequentially rotated within the range of rotation angles required to capture all the objects 21 to be examined, the line sensors are displayed in the horizontal direction on the matrix of the image memory. Two-dimensional image data is constructed in which each pixel corresponds to the rotation angle of the electric pan head in the vertical direction.

Next, processing when the image processing apparatus according to this embodiment is applied to shape inspection of pressed parts will be explained using a flowchart shown in FIG. Here, the object to be inspected is a press-formed part 21 as shown in FIG. 2, and the inspection content is to inspect the presence or absence and position of holes in the part.

First, two-dimensional image data is created in the image memory by sequentially inputting image data of the object to be examined according to the above-mentioned action (
Step 110). Next, the created two-dimensional image data is processed according to predetermined calculations, and each hole is labeled (step 120).

Next, the inspection process is repeated for the number of holes, but first, the parameter E for performing the repeat process is set to the initial value rOJ (step 130), and then the repeat loop (steps 140 to 180) is performed. Next, the parameters are updated (step 140), and the center position of the hole is calculated based on the arithmetic-processed data obtained in step 120 (step 150). next,
A comparison is made with the center position data of a standard pattern set in advance, and it is determined whether the center position data is within a predetermined tolerance range (step 160). As a result of the determination, if the tolerance is exceeded, a message such as that no hole is formed is displayed on the image output device (step 170), and the process proceeds to step 180. If it is within the allowable range, the process proceeds to step 180 to check whether the parameter (2) is equal to the number P of holes to be inspected in the press-formed part 21, that is, to inspect all the holes that should have been formed. If they are not equal, the process returns to step 140 and repeats the repeat loop until ■=P, and the inspection process ends.

[Effects of the Invention] As explained above, according to the present invention, since the imaging means having a plurality of linearly arranged light receiving elements is rotated by the rotating means around the arrangement direction of the light receiving elements, The entire object under test can be obtained in one image with high resolution using an inexpensive imaging means, and as a result, it can contribute to accurate image recognition of the object under test.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention applied to an image processing device, FIG. 2 is a diagram showing an embodiment of the image processing device of FIG. 1 applied to shape inspection, and FIG. 3 1 is a waveform diagram of the control signal shown in FIG. 1, and FIGS. 4 and 5 are diagrams for explaining the operation of the image processing apparatus shown in FIG. 1. 1... One-dimensional COD camera 3... Electric pan head 5... Control unit 7... Pan head drive unit 9... Image input unit 13... Clock generator 15... N-ary counter W B 2゜0-FJ one------

Claims (1)

[Claims] an imaging means having a plurality of linearly arranged light receiving elements;
An image input device comprising: a rotation means for rotating the imaging means around the arrangement direction of the light receiving elements.