JPS60154144A - Detecting method of excessive glossy surface body - Google Patents

Abstract

PURPOSE:To detect an unnecessary excessive glossy surface body by extracting only the high reflection component of a glossy surface body from a video signal, calculating the actual presence area of the glossy surface body on the basis of the extracted signal, and comparing the actual presence area with a predetermined presence area of the glossy surface body. CONSTITUTION:An image of the object position on a substrate 6 is picked up by a television camera 9 to supply the obtained video signal to a binary coding circuit 11, which performs binary coding operation on the basis of a threshold level for extracting only the high reflection component from a soldering position 2 and a solder sticking position of a solder bridge 2A, etc., and suplies the binary-coded signal to a signal processing part 12. The signal processing part 12 consists of a processor and various kinds of memory, etc., and the processor executes the program in memory to perform signal processing operation; the position of the solder sticking part is judged and compared with the presence area of the soldering position based upon a predetermined standard pattern to detect the sticking of excessive solder at the solder bridge 2A, etc., and a cathode-ray tube display device 13 is controlled according to the detection result to make a prescribed display.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a method for automatically detecting the presence of an object with a shiny surface, such as a solder attachment site, at a position other than the desired foot position. .

[Prior art]

In order to automatically inspect the quality of soldering on printed circuit boards, etc., the conventional method was to irradiate the soldering area with a beam of light from only one direction, image the target area with a television camera, and then The video signal obtained by the method is binarized, and based on this 2@ conversion signal, the position of the solder 1 spot and the adhesion of unnecessary 1 solder such as air solder bridges are detected. .

However, with conventional means, not only the area where solder 1 is attached, but also the surrounding conductor patterns and silk-printed symbols have high reflectance, making it impossible to distinguish between these and the area where solder 1 is attached. 10,000, if you set the threshold and hold level to a high value to obtain a binary signal, 1 solder
Only the highly reflective parts of the attachment site are extracted as individual dots,
% Kendade has the drawback that detection of the location of the adhesion site is inaccurate.

In addition, a means for three-dimensionally recognizing the shape of a target object using scanning irradiation using a slit beam or a spot beam has also been developed, but in this case, the disadvantage is that the apparatus is large-scale and expensive.

[Summary of the invention]

The purpose of the present invention is to fundamentally solve the drawbacks of the conventional methods. After extracting only the high-reflectance components of the The present invention provides an extremely effective method for detecting unnecessary glossy surface surplus objects.

〔Example〕

Hereinafter, the present invention will be explained in detail with reference to figures showing examples.

FIG. 1 is a diagram showing the state of irradiation of light beams, in which a number of light sources 3a are applied to the air soldering area 2 formed on the land 1 made of a conductor and its surroundings from diagonally above in each direction around the area.
~3h simultaneously irradiates light rays, and light sources 3a~3
If you use a high-intensity point light source such as an incandescent light bulb as h, the solder area 2 and 1 will be solder.
Since the surfaces of the two bridge members are glossy, high reflection areas corresponding to the light sources 3a to 3h are generated at the 'solder' attachment area 2, and high reflection areas are also generated at the 'solder' bridge 2A. A threshold level for capturing an image of the target part from the visual direction using a television camera, etc., and extracting only the medium and high reflection components of the reflected light based on the irradiation by the light sources 3a to 3h of the soldering part 2 and the soldering bridge 2A. Alternatively, if the video signal obtained by imaging is binarized, unnecessary reflected light components will be removed, and the second
The image shown in the figure is obtained.

That is, from 1 soldering part 2, the light source 38 to 3h
Correspondingly, the same number of luminances 4a to 4h as these are obtained by the high reflection component, and each bright spot 4a to 4h indicates the position of the V-solder "position 2", and the bright spots 4A, 4 B
This indicates the existence of two solder bridges.

3 to 5 are diagrams of light irradiation and imaging situations showing other embodiments. In FIG. 3, 'solder'
A light source 3 is suspended by an arm 5 whose rotation center is directly above the target area 2 and its surroundings, and is rotated around the area to be imaged. Imaging is repeatedly performed from above in synchronization with the rotation of the light source 3. The image shown in FIG. 2 can be obtained by processing the video signals obtained from each imaging and combining them in the same manner as described above.

FIG. 4 shows a case in which a plurality of single solder areas 2a to 2c scattered on the printed circuit board 6 are to be targeted.
A plurality of light sources 3a to 3h simultaneously irradiate light beams from above around the periphery of the printed circuit board 6.
In addition, the imaging field of view is limited for signal processing, and the television camera is moved depending on the target object, such as the soldering parts 2a to 2c, or the television camera is fixed and the imaging field of view is limited for signal processing. shall be moved.

In addition, in FIG. 5, the light sources 3a to 3h and the television camera 9 are integrated into a ring 7 and an arm 8, and are movable while being supported by a support mechanism not shown in the figure. The entire system is moved simultaneously.

FIG. 6 is a block diagram showing the electrical configuration of the board 6.
The target area is imaged by a television camera 9, and the video signal obtained by this is given to the binarization circuit 11, where the -solder area 2 and air solder bridge 2A etc. 'Binarization is performed using a threshold level that extracts only the high reflection component from the attachment site, and this binarized signal is given to the signal processing section 12.

The signal processing unit 12 is composed of a processor and various types of memory, etc., and the processor executes a program in the memory to perform signal processing operations.1 The signal processing unit 12 judges the position of the solder attachment site, and also determines the position of the solder attachment site. Based on the standard pattern, 1 is a person, and by comparison with the area where the adhesion site exists, there is 1 solder, 2 people on the bridge, etc.
Detects the adhesion of
3 and performs a predetermined display.

FIG. 7 is a flowchart of the signal processing operation by the processor, in which the 12-valued signal from the binarization circuit 11 is stored in the memory (step 101), and the 1-solder adhesion real area is determined from the bright spot. 102, - Compare the real domain and the existential domain' 103, and then find out whether the real domain is the existential domain? 〃According to N-0 of 104, existential area = existential area? “Check 105, this is YES
If so, it is determined that the condition is good, and an 'OK display' 106 is displayed on the cathode ray tube display #13.

Regarding the above, if step 104 is YES, since there is a surplus 1 solder adhesion site such as 2 solder bridges, etc., 1 surplus 1 solder adhesion/display 1o7 is performed on the CRT display 13. , step 105O
In response to NO, since 1 solder of the required part is not attached, 1v' solder is not attached or soldered as in step 107.
Display 108 is performed.

However, the irradiation direction of the light source 3 may be determined by adding the chromatic number and the irradiation angle according to the conditions, and the same can be done by using the television camera 9 11 or using another imaging device. It is optional to display the display using an indicator light or sound, and the display can be applied not only to the 'solder' adhesion site but also to various objects having a glossy surface.

Furthermore, in FIG. 7, steps 104 and 105 may be interchanged, and in some cases, the same result can be obtained even if step 104 is omitted, and the present invention can be modified in various ways.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, the influence of reflected light from other than the target shiny surface object is eliminated, and the location of the shiny surface object can be reliably determined based on the high reflection component. By comparing the actual area and the standard existing area according to this, the detection of objects with excessive glossy surfaces can be performed accurately, and this can be used for automatic inspection of various objects with glossy surfaces.
Remarkable effects can be obtained.

[Brief explanation of drawings]

The figures show an embodiment of the present invention. 2.2a to 2c. 2.2a to 2c. 2.2a to 2c. 2.2a to 2c. 2.2a to 2c. ... Middle 1 soldering part (glossy surface object), 2A ... 1 solder I bridge (glossy surface excess object), 3, 3a to 3h ... light source, 9 ... television camera, 11e: Binarization circuit, 12: Signal processing section. Patent applicant: Hitachi Electronics Co., Ltd. Agent: Masaki Yamakawa (#1 or 2) Fig. 1 30 Fig. 4 Fig. 6

Claims (1)

[Claims] A glossy surface object and its surroundings are irradiated with light beams from the surroundings to image the object and its surroundings, and a high reflection component of the light reflected by the irradiation of the object is extracted from the video signal obtained by the imaging; The present invention is characterized in that the actual area of the glossy surface is determined based on the signal obtained by the method, the actual area is compared with a predetermined existing area of the object, and an excess object on the glossy surface is detected according to the comparison result. A method for detecting objects with excessive glossy surfaces. □