JPH04102051A - Apparatus for inspecting appearance - Google Patents

Abstract

PURPOSE:To perform stable inspection even if there is a fluctuation in position of an object and a fluctuation in position of a characteristic image within the object by inspecting by means of creating inspection areas corresponding to an outer position and an inner characteristic position of the object. CONSTITUTION:A TV camera 1 converts an image of an object to an electric signal, while an A/D-converter 2 converts its concentration signal into a binary digital signal. An X, Y detecting unit 3 detects the upper end position U1 and the left end position L1 of the object from the binary image, and a microprocessor 8 sets an inspection area of a shape in an area creating unit 5. The creating unit 5 creates an inspection area A1 for the binary image, while an X, Y detecting unit 4 detects the upper end position U2 and the left end position L2 of a characteristic image PT of the object and the processor 8 sets an inspection area of the shape in an area creating unit 6. The first area A1 and a second area A2 are created from the creating units 5, 6, while a characteristics extracting unit 9 extracts an appropriate characteristic amount, which is to be compared with a predetermined reference value so that inspection is made as to whether the object is good or defective. Thus stable inspection is possible.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention converts an object image into an electrical signal using an imaging device including a television camera, and processes this to determine the external shape and internal characteristics of the object. The present invention relates to an appearance inspection device that enables inspection according to shape.

[Conventional technology]

Conventionally, this type of visual inspection equipment detects the external position of the target object and generates an inspection area corresponding to that position, thereby enabling inspection regardless of changes in the position of the target object. Are known.

[Problem to be solved by the invention]

However, although such a device can deal with changes in the position of the object, there is a problem in that it cannot deal with changes in the position of characteristic images within the object.

Therefore, an object of the present invention is to provide an appearance inspection apparatus that can handle not only the positional change of an object but also the case where there is a positional change of a characteristic image within the object.

[Means to solve the problem]

At least binarize the image obtained by imaging the object,
In a visual inspection device that performs predetermined arithmetic processing based on a binarized image to inspect an object, it includes a first detection means that detects the upper edge and left edge of the object, and a first detection means that detects the upper edge and the left edge of the object based on the detected positions. a first area generating means for generating a first inspection area set in advance according to the external shape of the object; and a first area generating means for detecting the upper and left edges of a characteristic image of the object within the generated first inspection area. 2 detection means, and a second area generation means for generating a preset second inspection area according to a characteristic image of the object based on the detected position, and Images of a third area of the first inspection area excluding the second inspection area are processed to enable inspection of the object.

[Operation] In addition to detecting the external position of the object, it also detects the position of the characteristic image within the object, and generates and inspects inspection areas corresponding to the external position and internal characteristic image position, respectively. To perform stable inspection not only when there is a positional change of an object but also when there is a positional change in a characteristic image within the object.

〔Example〕

FIG. 1 is a block diagram showing an embodiment of the invention. In the figure, l is a television camera as an imaging device, 2 is an analog/digital (A/D) converter, 3 and 4 are x,
X for y-coordinate position detection.

Y detection unit, 5.6 is an area generation unit for generating a predetermined inspection area, 7 is an image memory, 8 is a microprocessor as an image processing device, 9 is a feature extraction unit, 10
is a bus.

FIG. 2 is an explanatory diagram for specifically explaining this invention.
Below cylinder 1. Its operation will be explained with reference to FIG.

That is, the television camera 1 converts an object image into an electrical signal, and the A/D converter 2 converts the gray level signal into a binary digital signal (binarized signal).

An example of a binarized image is shown in FIG. 2 with the symbol PO.

The X, Y detection unit 3 detects from the converted binarized image the upper end position of the object (symbol Ul in FIG. 2) as the position where the image first appears when viewed from above (in the Y-axis direction), and The left end position of the object (labeled Ll in FIG. 2) is detected as the position where the image appears. The detected position is read by the microprocessor 8, and an inspection area of a predetermined shape is set in the area generation section 5 accordingly.

On the other hand, the A/D converted binary image is stored in the image memory 7 at the same time as the position is detected. The area generation unit 5 generates a predetermined inspection area as shown by the dotted line A1 in FIG. 2 from the stored binarized image at the detected position U1. (generated inside it to have some margin for Ll), X.

The Y detection unit 4 detects a characteristic image PT of the object within this area.
The upper end position U2 and the left end position L2 are X.

Detection is performed in the same manner as the Y detection section 3. The detected position is read by the microprocessor 8, and an inspection area of a predetermined shape is set in the area generation section 6 accordingly.

Thereafter, the binarized image is taken out from the image memory 7, and the area generation units 5 and 6 generate predetermined first areas At and second areas A2, respectively.The second area is located at the detected position U2.゜Generated outside of L2 to have some margin), the feature extraction unit 9 includes the area from the second area and the third area obtained by removing this second area from the first area. Appropriate feature quantities are extracted, and their quality is inspected by comparing them with predetermined reference values.

In this way, the position of the characteristic image of the object is also detected and a fixed inspection area is generated accordingly, allowing for stable inspection even when the position of the characteristic image within the object varies. can be done.

〔Effect of the invention〕

According to this invention, not only the external position of the object is detected, but also the position of the characteristic image within the object is detected, and inspection areas corresponding to the external position and internal characteristic image position are respectively generated and inspected. This makes it possible to perform stable inspection not only when there is a change in the position of the object, but also when there is a change in the position of the characteristic image within the object.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the invention, and FIG. 2 is an explanatory diagram for specifically explaining the invention. 1...TV camera, 2...A/D converter, 3.4
...X, Y detection section, 5.6... Area generation section, 7
...Image memory, 8...Microprocessor, 9.
...Feature extraction unit, 10...Bath, PO...Object image, PT...Intra-object feature image, Ul...Top position of object, Ll...Left end position of object, U2... upper end position of the feature image within the object, L2... left end position of the feature image within the object, AI... first inspection area, A2...
Second inspection area.

Claims (1)

[Scope of Claims] 1) An appearance inspection device that at least binarizes an image obtained by capturing an image of an object, and performs predetermined arithmetic processing based on the binarized image to inspect the object, comprising: a first detection means for detecting the upper end and the left end of the object; a first area generation means for generating a preset first inspection area according to the external shape of the object based on the detected position; a second detection means for detecting the upper end and left end of the characteristic image of the object within the first inspection area of the octopus; and a second inspection set in advance according to the characteristic image of the object based on the detected position. a second area generating means for generating an area, and processes an image of a third area excluding the second inspection area among the second inspection area and the first inspection area to generate a target area. Appearance inspection equipment that enables inspection of objects.