JP4599477B2 - High illumination illumination device for defect detection device and defect detection device - Google Patents

Description

  Line sensor camera (an element in which charge-coupled elements are arranged in a line, receives a linear reflected light from a sheet-like material, and generates an electric signal corresponding to the linear reflected light, The present invention relates to a high illuminance illumination device used for a defect inspection apparatus for a sheet-like article using a CCD camera) and a defect detection apparatus using the high illuminance illumination apparatus.

  In the surface inspection of a sheet-like object, the surface of the sheet-like object is irradiated with light, the reflected light from the surface of the sheet-like object is captured by a line sensor camera (CCD camera), and the intensity of the image light is converted into an electrical signal. Inspection of defects on sheet surface.

  As a typical one, by using a line sensor camera (CCD camera) that captures a sheet-like object that is traveling and captures it as an image, by examining the image captured by this line sensor camera (CCD camera), There is something that finds a fault. In such an inspection apparatus, a predetermined amount of brightness or more is required for image capturing. For this reason, some lighting means is usually used to illuminate the traveling sheet.

  As a light irradiation method by the illuminating means, a transmission method for inspecting a defect of the object to be inspected, which receives light from a light source that transmits the object to be inspected by a line sensor camera (CCD camera), and a light incident at a predetermined incident angle. Regular reflection system that inspects the defects of the object to be inspected by a line sensor camera (CCD camera) that receives light from the light source that is reflected by the surface of the object to be inspected at an angle of reflection, and light from the light source that is irregularly reflected by the surface of the object to be inspected An irregular reflection method for inspecting defects of an object to be inspected by a line sensor camera (CCD camera) is known.

Various illumination means can be used for this purpose, but a relatively inexpensive one such as a fluorescent lamp is employed, and a plurality of illumination means are used in parallel to increase the amount of light.
JP-A-10-160414 Japanese Patent Laid-Open No. 9-300596

  However, in the inspection system for sheet-like objects using a line sensor camera (CCD camera), when pursuing detection density with inspection resolution, it is essential to increase the camera running speed. If the scanning speed is increased, the line sensor camera The amount of light input to the (CCD camera) is insufficient, leading to a decrease in the S / N ratio, and the inspection apparatus using the current illumination device has reached the detection limit.

  Then, this invention makes it a subject to provide the line type high illumination intensity illuminating device which enables the acceleration of a camera travel speed.

When a plurality of fluorescent tubes are arranged in tandem along the radial direction, the light from the rear fluorescent tube is blocked by the front fluorescent tube, but the light is diffused as described above, and the light quantity is fluorescent. The amount is smaller than the amount of light irradiated from the side and rear of the tube and collected by the reflector.
That is, the light from the front surface of the fluorescent tube is diffused by the original function of the fluorescent tube and does not contribute much to the increase in illuminance on the irradiated surface, whereas the light from the side surface of the fluorescent tube has the shape of the reflective surface of the reflector. By specifying, the light is condensed and projected, and the illuminance on the surface of the object to be inspected can be increased.

The present invention has been made on the basis of the above-mentioned facts, and in order to solve the above-mentioned problems, the high-illuminance illumination device for a defect detection device of the invention of claim 1 is a tandem arrangement type disposed below an object to be inspected. A single-type lamp composed of a lamp, and a parallel-arranged lamp composed of a pair of cascade-arranged lamps arranged in parallel with a gap serving as an inspection through hole above the object to be inspected. It is composed of a plurality of fluorescent tubes arranged in tandem along the irradiation direction, and a concentrating reflector having a plurality of curved surfaces for reflecting the light from each fluorescent tube so as to collect it at the same focal point. It is characterized by that .

According to a second aspect of the present invention, there is provided a defect detection apparatus comprising a pair of lamps arranged in parallel with a single lamp composed of a column-arranged lamp disposed below the object to be inspected and a gap serving as an inspection through hole above the object to be inspected. Through a parallel-arranged lamp composed of the above-mentioned serially-arranged lamps, and through the inspection through-holes provided in the parallel-arranged lamp, the light emitted from the above-arranged vertically disposed lamps above the object to be inspected is increased. A defect detection apparatus having a line sensor camera (CCD camera) for imaging an inspection surface of an object to be illuminated, and a signal processor, wherein the columnar arrangement type lamps are arranged in a column along the irradiation direction. A plurality of fluorescent tubes, and a concentrating reflector having a plurality of curved surfaces for reflecting the light from each fluorescent tube so as to collect the light at the same focal point, and inspecting from a single lamp below The body is irradiated and passes through the object Light is received by the line sensor camera (CCD camera), and the light reflected on the surface of the object to be inspected from the upper parallel lamp is received by the line sensor camera (CCD camera). The amount of the above is converted into an electric signal, and the defect of the object to be inspected is detected based on the electric signal.

According to the high illuminance illumination device of the present invention, the illuminance at the inspection location can be increased, so that sufficient inspection and decomposition can be obtained even when the scanning speed of the line sensor camera (CCD camera) is increased.
Moreover, as shown in FIG. 7, the illumination means (vertical lamp, right side illumination device in FIG. 7) in which two fluorescent tubes are juxtaposed in the vertical direction is an illumination in which two fluorescent tubes are juxtaposed in the horizontal direction. Compared with the means (horizontal lamp, left side illumination device in FIG. 7), the high illuminance illumination device can be brought closer to the object to be inspected, so that high illuminance can be obtained.
In FIG. 7, in order to facilitate comparison, the vertical lamp and the horizontal lamp are displayed with the same volume.
Furthermore, in the third invention, since the high-illuminance illumination devices are arranged above and below the object to be inspected, the present invention can be applied to a defect detection device of either a transmission method or a reflection method.

  A plurality of fluorescent tubes arranged in tandem along the irradiation direction and a concentrating reflector composed of a pair of left and right reflectors that reflect the light from each fluorescent tube so as to collect the light at the same focal point. The lamps are configured, and a pair of tandem lamps are arranged so as to collect light from each lighting device at the same focal point.

An embodiment of the high illuminance illumination device (single lamp) 10 of the present invention will be described with reference to FIGS.
In addition, although the Example using two fluorescent tubes is described below, as long as the arrangement direction is the same, you may employ | adopt not only two but more fluorescent tubes.

In this embodiment, the two fluorescent tubes 11 arranged in tandem along the irradiation direction, and the condensing reflecting plate 13 that reflects the light from each fluorescent tube 11 so as to collect the light at the same focal point, are of a single type. A lamp 10 is configured.
As shown in FIGS. 1 and 2, the condensing reflecting plate 13 includes a first curved surface (a bowl-shaped concave mirror) 14 that reflects light from the upper fluorescent tube 11 in the focal direction, and a first curved surface 14. It is formed with a second curved surface (a bowl-shaped concave mirror) 15 that continuously reflects light from the lower fluorescent tube 11 in the focal direction.
The fluorescent tube is preferably a compact fluorescent tube in which a fluorescent tube having a tube diameter of about 17 mm is joined in a U shape, but a normal fluorescent tube may be used in parallel.

  When the fluorescent lamp 11 is turned on, the single-type lamp 10 having the above-described configuration condenses the light hitting the condensing reflecting plate 13 at one point (one line) on the surface of the inspection object 50 as shown in FIG. Increase illuminance. Further, since the illuminance and the illumination width change by adjusting the height of the stand-alone lamp 10 from the focal point of the object 50 to be inspected, the illuminance can be adjusted according to the type of the object 50 to be inspected and the moving speed of the object to be inspected. Can be adjusted.

  Using a column-arranged lamp (right illumination device in FIG. 7) and a row-arrangement lamp (illumination device on the left side in FIG. 7) composed of fluorescent tubes of the same standard, as shown in FIG. As a result of conducting a comparative test of the illuminance at the position, the results shown in the following table and FIG. 9 were obtained.

The table below shows the comparison between the illuminance when the distance from the metal outlet of the row-type lamp is 100 mm and the illuminance under other conditions.

  As shown in the above table and FIG. 9, the columnar arrangement type lamps obtained higher illuminance than the row arrangement type lamps at all positions from the metal outlet.

  An embodiment of the high illuminance illumination device (parallelly arranged lamp) 20 of the present invention will be described based on FIGS.

As shown in FIGS. 3 and 4, the single lamp 10 of the above embodiment is projected at the same incident angle with the irradiation direction inward so that the light from the pair of lamps 10 and 10 is condensed at the same focal point. The lamps 20 are arranged in parallel with a gap in the housing 21 to form a parallel-arranged lamp 20.
In addition, when the line sensor camera (CCD camera) 30 and the tandem-arranged lamps 20 are arranged in a straight line on the upper surface of the housing 21, the parallel-arranged lamps 20 are formed so that the inspection object 50 can be seen from above. An inspection through hole 22 is provided opposite to a gap formed between the pair of individual lamps 10 and 10.

  An embodiment of a defect detection apparatus using the high illumination illumination device (single lamp 10 and parallel lamp 20) of the present invention will be described with reference to FIGS.

  FIG. 5 shows an embodiment in which the advanced illumination device (single lamp 10 and parallel-arranged lamp 20) of the present invention is used as a defect detection device, and the defect detection device is arranged in a column arranged below the object to be inspected. A line sensor camera that images the inspection surface of the inspection object 50 through the inspection lamp 50, the parallel-arrangement-type lamp 20 disposed above the object to be inspected, and the inspection through holes 22 provided in the parallel-arrangement lamp 20. CCD camera) 30.

The light irradiated from the single-type lamp 10 to the object to be inspected 50 passes through the object to be inspected 50 and enters the line sensor camera (CCD camera) 30, and the light irradiated from the parallel lamp 20 to the object to be inspected 50 It is reflected by the surface of the object to be inspected 50 and enters a line sensor camera (CCD camera) 30 where it is converted into an electrical signal. The electrical signal is sent from the line sensor camera (CCD camera) 30 to a signal processor (not shown). After being sent, it is recognized as a defect through a detection circuit / determination circuit.
Note that the tandem lamp 10 is used to increase the illuminance on the inspection surface by irradiating from below when the inspection object 50 is translucent. When the inspection object 50 is made of a non-transparent material, Irradiation from below the object to be inspected by the single lamp 10 is not necessary.

  When a defect is detected, the signal processor notifies the existence of the defect by operating a marker, a rotating lamp, a printer, etc., or displaying a defect image on the PC screen.

  FIG. 6 shows the arrangement of the line sensor camera (CCD camera) and the illuminating device of the defect detection apparatus shown in FIG. 5. As the light projection system, the transmission system and the reflection system are used depending on the properties of the object to be inspected. , A combination of both types can be employed.

As described above, the high-illuminance illumination device of the present invention can be used for sheet defect inspection.
It can also be used for inspection of printed matter. A printed matter that is printed using a plurality of inks often has a defect such as a misaligned character missing, and it is preferable to find such a defect early and eliminate the cause. It can also be used as an inspection device for detecting defects in printed matter.

  In addition, the defect detection device using the high-illuminance illumination device of the present invention can detect dirt, pinholes, and attached foreign matter, so that not only the printing industry, but also the film industry, paper industry, nonwoven fabric industry, plastic industry, metal It can be used in industries that handle sheet-like and plate-like bodies such as the industry, FPD industry, and board industry.

It is sectional drawing of a high illumination intensity illuminating device (single type lamp). It is explanatory drawing of the condensing state of a high illumination intensity illuminating device (single type lamp). It is sectional drawing of a high illumination intensity illuminating device (parallel arrangement type lamp). It is explanatory drawing of the condensing state of a high illumination intensity illuminating device (parallel arrangement type lamp). It is the schematic of the Example applied to the fault detection apparatus. It is arrangement | positioning of a line sensor camera (CCD camera) and a high illumination intensity illumination apparatus. It is explanatory drawing of the effect of this invention. It is explanatory drawing of illumination intensity test conditions. It is explanatory drawing of an illumination intensity test result.

Explanation of symbols

10 Single-type lamps (tandem-type lamps)
DESCRIPTION OF SYMBOLS 11 Fluorescent tube 12 Metal mouth 13 Condensing reflecting plate 14 1st curved surface 15 2nd curved surface 20 Side by side lamp 21 Case 22 Through-hole 30 for inspection Line sensor camera (CCD camera)
40 Illuminance meter 50 Inspected object (sheet-like object)
60 Row-type lighting fixtures

Claims (2)

A parallel-type lamp composed of a single-type lamp composed of a column-arranged lamp disposed below the object to be inspected and a pair of cascade-arranged lamps disposed in parallel with a gap serving as an inspection through hole above the object to be inspected A plurality of fluorescent tubes arranged in a row along the irradiation direction, and a plurality of fluorescent tubes for reflecting the light from each fluorescent tube so as to collect the light at the same focal point. A high illuminance illumination device for a defect detection device, comprising a condensing reflector having a curved surface . A parallel-type lamp composed of a single-type lamp composed of a column-arranged lamp disposed below the object to be inspected and a pair of cascade-arranged lamps disposed in parallel with a gap serving as an inspection through hole above the object to be inspected And the inspection surface of the object to be inspected that is illuminated with high illuminance by the light emitted from the vertically arranged lamp from above the object to be inspected through the inspection through-hole provided in the parallel-arranged lamp. A defect detection apparatus having a line sensor camera for imaging , and a signal processor, wherein the tandem lamps are arranged in a row along the irradiation direction, and light from each fluorescent tube A line sensor camera that is composed of a condensing reflector having a plurality of curved surfaces for reflecting so as to be focused at the same focal point, and that has been irradiated onto the object to be inspected from a single independent lamp below and has passed through the object to be inspected. in receiving, over the parallel The line sensor camera receives the light that is irradiated on the object to be inspected from the table lamp and reflected on the surface of the object, converts the amount of the received light into an electrical signal, and detects the defects of the object to be inspected based on the electrical signal. A defect detection apparatus characterized by: