KR100969283B1 - Apparatus for optical inspection - Google Patents

Abstract

The present invention relates to an optical inspection apparatus that can prevent distortion caused by bending, sagging or the like of an inspection object. The optical inspection apparatus of the present invention comprises: a stage on which an inspection object is placed; A photographing unit for photographing a test object placed on the stage; Illumination unit for irradiating light to the inspection object; And rolling members supporting edges of the area photographed by the photographing unit to maintain flatness of the photographing area.

Printed Circuit Board, Cloud Member

Description

Optical inspection device {APPARATUS FOR OPTICAL INSPECTION}

1 is a front view for explaining the configuration of an optical inspection device according to an embodiment of the present invention.

2 is a side view for explaining the configuration of an optical inspection device according to an embodiment of the present invention.

3 is a view showing a state in which a pair of rolling members support both ends of the imaging area w.

4 is a view showing an installation example of a cloud member when using an area scan camera.

5 is a front view for explaining the configuration of an optical inspection device according to a second embodiment of the present invention.

6 is a side view for explaining the configuration of an optical inspection device according to a second embodiment of the present invention.

7 is a view showing a state in which 12 balls support both ends of the imaging area w.

Explanation of symbols on the main parts of the drawings

100: stage

200: linear movement unit

300: recording unit

400: lighting unit

500: cloud member

The present invention relates to an optical inspection apparatus for a printed circuit board, and more specifically, to photograph a pattern formed on an inspection object (printed circuit board) and process the captured image information to inspect whether there is a defect in the pattern formed on the inspection object. It relates to an optical inspection device.

Various printed circuit boards are rapidly changing from rigid rigid printed circuit boards to flexible printed circuit boards so that the line width of the circuit board becomes thinner and applicable to various types of products due to slim and thinning of various electronic products. Is changing. Therefore, as the line width becomes thinner, the inspection by the human eye becomes more and more difficult, and the problem of the productivity decrease due to the human eye is raised, and the introduction of the automatic optical inspection system becomes necessary to overcome this.

In other words, the manufacturers of printed circuit boards can effectively and promptly inspect the appearance inspection items such as plating areas, solder resist areas, and semiconductor wafer areas (inner lead parts) during product inspection. Inspection is a key to productivity and quality control, and especially when inspecting large glass substrates (circuit boards), maintaining flatness for stable inspection is a key.

The present invention is to provide an optical inspection device capable of a stable inspection of the circuit board.

The present invention is to provide an optical inspection device that can be inspected while maintaining the flatness of the circuit board.

The present invention provides an optical inspection apparatus capable of inspecting a circuit board using transmitted light and reflected light.

An optical inspection apparatus of the present invention for achieving the above object is a stage on which an inspection object is placed; A photographing unit for photographing a test object placed on the stage; Illumination unit for irradiating light to the inspection object; And rolling members supporting edges of the area photographed by the photographing unit to maintain flatness of the photographing area.

According to an embodiment of the present invention, the rolling member is a ball caster having a ball in rolling contact with the inspection object.

According to an embodiment of the present invention, the optical inspection apparatus further includes a linear movement unit for moving the stage in the front-rear direction so that the photographing unit can continuously photograph the inspection object.

According to an embodiment of the present invention, the photographing unit includes a line scan camera photographing by a line scan method, and the cloud member supports both ends of the photographing area photographed by the line scan camera.

According to an embodiment of the present invention, the photographing unit includes an area camera photographing by an area scan method, and the cloud member supports edges of the photographing area photographed by the area camera.

According to an embodiment of the present invention, the illumination unit includes at least one of a transmission light for irradiating the transmitted light to the inspection object, and a reflection light for irradiating the reflected light to the inspection object.

According to an embodiment of the present invention, the stage supports the left and right edges of the inspection object, and has a space open in the front and rear movement direction so that the rolling member is located below the inspection object.

According to an embodiment of the present invention, the stage has a body having a space opened in the front and rear moving direction so that the cloud member is located under the inspection object; It is provided on the top of the body and includes a supporter for supporting the left and right edges of the inspection object.

According to an embodiment of the invention, the stage further includes a positioning member for aligning the position of the inspection object placed on the supporter.

According to an embodiment of the invention, the optical inspection device is installed horizontally in the front and rear moving direction of the stage, and further includes a horizontal support that passes through the open space of the stage and the cloud member is installed.

An optical inspection apparatus of the present invention for achieving the above object is a stage on which an inspection object is placed; A photographing unit for photographing a test object placed on the stage; It includes a lighting unit for irradiating light to the inspection object; The stage includes a rolling member in cloud contact with the inspection object to maintain flatness of the inspection object.

According to an embodiment of the present invention, the rolling member includes a plurality of balls supporting edges of the photographing area of the inspection object photographed by the photographing unit at predetermined intervals.

According to an embodiment of the present invention, the optical inspection apparatus further includes a linear movement unit for moving the stage to the photographing area of the photographing unit together with the rolling member so that the photographing unit photographs the inspection object continuously.

According to an embodiment of the invention, the illumination unit includes a transmission light for irradiating the transmitted light to the inspection object, and a reflection light for irradiating the reflected light to the inspection object.

For example, embodiments of the present invention may be modified in various forms, and the scope of the present invention should not be construed as being limited by the embodiments described below. This embodiment is provided to more completely explain the present invention to those skilled in the art. Accordingly, the shape of the elements in the drawings and the like are exaggerated to emphasize a clearer description.

An embodiment of the present invention will be described in detail with reference to FIGS. 1 to 7. In addition, in the drawings, the same reference numerals are denoted together for components that perform the same function.

The inspection apparatus of the present invention is well suited for inspecting large circuit boards. In particular, it is very suitable for inspecting large circuit boards in which warpage is generated due to its own weight, which makes it difficult to maintain flatness. Here, the inspection object may be a circuit board with glass attached to the bottom surface, a glass substrate on which a circuit pattern is formed, and a wide circuit board.

(Embodiment 1)

1 is a front view for explaining the configuration of an optical inspection device according to a first embodiment of the present invention, Figure 2 is a side view for explaining the configuration of an optical inspection device according to a first embodiment of the present invention.

1 and 2, the optical inspection apparatus 10 of the present invention includes a stage 100, a linear movement unit 200, a photographing unit 300, an illumination unit 400, and a cloud member 500. do.

(stage)

The stage 100 includes a body 110 that includes a bottom surface 112, a first side surface 114, and a second side surface 116. The supporter 120 and the positioning member 130 are installed at an upper end of the body 110, that is, at an upper end of the first and second side surfaces 114 and 116. The inspection object s is placed with both edges supported by the supporter. The positioning member 130 is a cylinder for aligning both sides of the inspection object s placed on the supporter 120, and presses both sides of the inspection object to correct (align) the left and right positions. On the other hand, the body 110 is provided with a space between the first and second side surfaces 114 and 116, the space is opened in the upper and front and rear directions.

The stage 100 is moved in the front-rear direction on the base plate 20 by the linear movement unit 200. The linear movement unit 200 includes an LM guide 210 and a linear motor 220. The stage 100 is guided by the LM guide 210 installed in the base plate 20 and moved in the front-rear direction by the linear motor 220. In the present embodiment, the linear movement unit 200 is shown and described as an LM guide and a linear motor, but various mechanisms for linearly moving the rotational force of the motor using a chain, a belt, or a ball screw may be applied.

(Shooting unit)

The photographing unit 300 is a CCD camera having an image sensor such as a CCD line sensor and a lens (not shown). The photographing unit 300 photographs a surface (pattern, etc.) of the inspection object s to capture image data of the inspection object s. You get it. The image data thus obtained is provided to an image processor (not shown). Although not shown, the optical inspection apparatus naturally has an image processing unit that receives an image captured by the photographing unit, and the image processing unit is provided with a typical computer system (aka micom) to control various operations according to the automatic optical inspection, Will be processed. For example, a line scan camera may be used as the photographing unit 300, and a line scan camera or an area camera may be additionally installed according to the inspection conditions of the inspection object and the user's requirements. The photographing unit 300 is installed on the vertical frame 30 so as to be movable in the left and right directions. A moving plate 34 is installed on the guide rail 32 installed on the vertical frame 30, and a line scan camera, which is a photographing unit 300, is installed on the moving plate 34. That is, the photographing unit 300 can adjust the left and right positions according to the region to be photographed.

(Lighting unit)

The illumination unit 400 includes a transmission light 410 for irradiating the transmitted light to the inspection object (s), and a reflection light 420 for irradiating the reflected light to the inspection object (s). The reflection light 420 is disposed above the inspection object s, and the transmission illumination 410 is disposed below the photographing area of the inspection object s. The reflection light 420 and the transmission light 410 output light for acquiring image data of the photographing area of the inspection object s. As the light sources of the reflection light 420 and the transmission light 410, a plurality of linear light emitting diodes, linear tube fluorescent lamps, halogens, metal halides, and the like may be used. This can be installed. Reflective light 420 is installed on the moving plate 34, the transmission light 410 is fixed to the horizontal support 600. The transmission light 410 and the reflection light 420 may adjust the height.

(Cloud member)

The cloud member 500, which is the most important component in the present invention, is to minimize distortion caused by bending and deflection of the photographing area of the inspection object (s), and photographing area (w) of the inspection object (s). And a ball caster having a ball 510 in direct contact with the edge. The rolling member 500 is installed on the horizontal support 600 to be positioned below the photographing unit 300. The rolling member 500 is a pair of pedestals 520 that are vertical to be positioned at a height such that the stage 100 is positioned below the photographing unit 300 for inspection to be in contact with the bottom of the inspection object s. It is located at the top. For reference, the pair of pedestals 520 is preferably installed to enable height adjustment on the horizontal support 600 for height adjustment of the cloud member 500. As shown in FIG. 2, the transmission light 410 is positioned between the pair of pedestals 520, and the horizontal support 600 is positioned below the transmission light 410.

(Horizontal support)

The horizontal support 600 is a structure in which they are fixed so that the cloud member 500 and the transmission light 410 may be positioned in the open space of the stage 100 moved in the front-rear direction. The horizontal support 600 is positioned horizontally in the front and rear movement direction of the stage 100 and crosses the open space of the stage, and both ends are installed on the fixing base 610 installed on the base plate 20. The horizontal support is provided with rolling members and through-lights.

3 is a view showing a state in which a pair of rolling members 500 support both ends of the imaging area (w). As shown in FIG. 3, since the photographing unit is a camera photographing by a line scan method, the cloud contact the bottom surface of the inspection object s corresponding to both ends of the region w captured by the two cloud members 500. And the photographing unit continuously photographs the inspection object s moving in the direction of the arrow (front and rear). At this time, the photographing by the photographing unit is made in a state where the flatness is maintained by a pair of rolling member 500. Although only a pair of rolling members are shown in this embodiment, a plurality of rolling members may be installed as necessary.

4 is a view showing an installation example of a cloud member when using an area scan camera.

As shown in FIG. 4, in the case of the camera line photographed by the area scanning method, as shown in FIG. 4, four cloud members 500 are disposed at four corners of the rectangular photographing area w, respectively. As a result, the bottom surface of the inspection object s is supported by cloud contact, and since the photographing is performed while the flatness of the photographing area is maintained, a reliable inspection is possible.

In this embodiment, the stage is shown as being photographed while scanning moving, as another example, the stage on which the inspection object is placed is photographed while the photographing unit, the lighting unit, and the cloud member are fixed while the scanning unit is fixed. It is also possible. For example, the photographing unit, the lighting unit and the cloud member may be additionally installed according to the inspection conditions of the inspection object and the user's requirements.

(Second Embodiment)

5 is a front view for explaining the configuration of the optical inspection device according to a second embodiment of the present invention, Figure 6 is a side view for explaining the configuration of the optical inspection device according to a second embodiment of the present invention.

An important feature of the second embodiment is that, unlike the method of the first embodiment, in which the photographing unit, the lighting unit, and the cloud member are fixed and the inspection object is moved while the stage is fixed, in the second embodiment, the photographing unit and the lighting unit are In the fixed state, the rolling member and the stage move together to change the inspection object inspection method.

5 and 6, the optical inspection apparatus 10a of the present invention includes a stage 100a, a linear movement unit 200a, a photographing unit 300a, an illumination unit 400a, and a cloud member 500a. Include.

The stage 100a includes a body 110 including a bottom surface 112, a first side surface 114, and a second side surface 116. The supporter 120 and the positioning member 130 are installed at an upper end of the body 110, that is, at an upper end of the first and second side surfaces 114 and 116. The inspection object s is placed with both edges supported by the supporter 120. The positioning member 130 is a cylinder for aligning both sides of the inspection object s placed on the supporter 120, and presses both sides of the inspection object to correct (align) the left and right positions. On the other hand, the body 110 is provided with a space between the first and second side surfaces 114 and 116, the space is opened in the upper and front and rear directions.

On the other hand, the rolling member 500a is installed in the stage 100a. The rolling member 500a is disposed directly below the line on which the inspection object s is positioned so as to support the bottom of the inspection object s placed on the stage 100a, and the rolling members 500a and 114 are provided on the first and second side surfaces 114 and 116. It is installed on the bracket 190 extending from the formed.

The rolling member 500a is for minimizing distortion caused by bending and deflection of the photographing area of the inspection object s placed on the stage 100a, and the edge of the photographing area w of the inspection object s. And a ball caster having balls 510 in direct contact with it. The rolling member 500a is moved to the stage by being installed on the stage so as to be positioned under the inspection object. Accordingly, the balls of the rolling member are kept in point contact with the inspection object at regular intervals, and the friction is not generated due to the relative movement of the ball and the inspection object as in the first embodiment. The rolling member 500a is installed on the bracket 190 to be positioned at a height such that the bottom surface of the inspection object s can contact the cloud when the inspection object is placed on the stage. Although not shown, the bracket 190 is preferably installed on the first and second side surfaces 114 and 116 of the stage 100a to adjust the height of the cloud member 500a.

As shown in FIG. 7, the balls of the rolling member 500a are installed at regular intervals to support the inspection object s as a whole. For example, if the four balls arranged on all four sides are 100mm, the flatness can be maintained at 100mm, and six balls are arranged in two rows at 100mm intervals when the area (the length of the inspection object) for imaging the image is, for example, 500mm. Therefore, a total of 12 balls 510 are required.

Referring to FIG. 7 again, the bottom surface of the inspection object s corresponding to both ends of the area w in which six balls are captured in two rows on both sides is supported by cloud contact, and the photographing unit moves in the direction of the arrow (front and rear). Continuous shooting of the inspection object (s) moving to. At this time, the photographing by the photographing unit is made in the state of maintaining the flatness by the 12 balls.

The rolling member 500a and the stage 100a are moved in the front-rear direction on the base plate 20 by the linear movement unit 200a. The linear movement unit 200a includes an LM guide 210 and a linear motor 220. The stage 100a is guided by the LM guide 210 installed in the base plate 20 and moved in the front-rear direction by the linear motor 220. In this embodiment, although the linear movement unit 200a is illustrated and described as the LM guide and the linear motor, various mechanisms for linearly moving the rotational force of the motor using a chain, a belt, or a ball screw may be applied.

The photographing unit 300a is a CCD camera having an image sensor such as a CCD line sensor and a lens (not shown). The photographing unit 300a photographs the surface (pattern, etc.) of the inspection object s to capture image data of the inspection object s. You get it. The image data thus obtained is provided to an image processor (not shown). Although not shown, the optical inspection apparatus naturally has an image processing unit that receives an image captured by the photographing unit, and the image processing unit is provided with a typical computer system (aka micom) to control various operations according to the automatic optical inspection, Will be processed. For example, a line scan camera may be used as the photographing unit 300a, and a line scan camera or an area camera may be additionally installed according to the inspection conditions of the inspection object and the user's requirements. The photographing unit 300a is installed to the left and right directions in the vertical frame 30. The moving plate 34 is installed on the guide rail 32 installed in the vertical frame 30, and the line scanning camera serving as the photographing unit 300a is installed on the moving plate 34. That is, the photographing unit 300a may adjust left and right positions according to a region to be photographed.

The illumination unit 400a includes a transmission light 410 for irradiating the transmitted light to the inspection object s and a reflection light 420 for irradiating the reflected light to the inspection object s. The reflection light 420 is disposed above the inspection object s, and the transmission illumination 410 is disposed below the photographing area of the inspection object s. The reflection light 420 and the transmission light 410 output light for acquiring image data of the photographing area of the inspection object s. As the light sources of the reflection light 420 and the transmission light 410, a plurality of linearly arranged light emitting diodes, linear tube fluorescent lamps, halogens, metal halides, etc. may be used. Etc. may be installed. Reflective light 420 is installed on the moving plate 34, the transmission light 410 is fixed to the horizontal support (600a). The transmission light 410 and the reflection light 420 may adjust the height.

The horizontal support 600a is a structure in which they are fixed so that the transmission light 410 may be positioned in the open space of the stage 100a that is moved in the front-rear direction. The horizontal support 600a is positioned horizontally in the front and rear movement direction of the stage 100a and crosses the open space of the stage, and both ends are installed on the fixing stand 610 installed on the base plate 20. The transmission light 410 is installed in the horizontal support 600a.

In the above, the configuration and operation of the optical inspection device according to the present invention is shown in accordance with the above description and drawings, but this is only an example, and various changes and modifications are possible without departing from the technical spirit of the present invention. Of course.

As described above, the present invention can prevent distortion caused by bending and deflection (deflection) of the photographing region of the inspection object.

The present invention can obtain an image having a stable focus.

The present invention can be inspected while maintaining the flatness of the inspection object.

The present invention can obtain a higher inspection quality for the inspection object.

Claims (15)

In the optical inspection device: A stage on which the inspection object is placed; A photographing unit for photographing a test object placed on the stage; Illumination unit for irradiating light to the inspection object; A rolling member disposed to fix a relative position with respect to the photographing unit and supporting an edge of the photographing area to maintain flatness of the photographing area which is an area photographed by the photographing unit; And It includes a linear movement unit for linearly moving the stage or the recording unit so that the relative position of the recording unit and the inspection object is changed, The stage is It has a space that is open in the direction of movement of the stage and the top, and includes a body on which the inspection object is placed, The rolling member is And the stage is positioned in the space of the body when the stage is positioned to face the photographing unit. The method of claim 1, The optical inspection device Further comprising a horizontal support extending in the space of the body, disposed in the moving direction of the stage, The rolling member is Optical inspection apparatus, characterized in that installed on the horizontal support in a position facing the photographing unit. The method of claim 2, The rolling member is A ball in contact with the bottom of the inspection object; To support the ball, including a pedestal fixed to the horizontal support, The pedestal is Optical inspection apparatus, characterized in that the height can be adjusted to change the relative distance between the inspection object and the ball. The method of claim 1, The photographing unit Including a line scan camera that shoots a line scan (line scan), The rolling member is And supporting both ends of the photographing area photographed by the line scan camera. The method of claim 1, The photographing unit It includes an area camera that shoots in an area scan (area scan) method, The rolling member is And an edge of the photographing area photographed by the area camera. The method of claim 1, The lighting unit Transmitted light irradiating the transmitted light to the inspection object; And Located between the photographing unit and the transmission light, the optical inspection device comprising a reflected light for irradiating the reflected light to the inspection object. delete delete The method of claim 1, The stage is A supporter provided at an upper end of the body and supporting an edge of the inspection object; And an positioning member for aligning the position of the inspection object placed on the supporter. delete In the optical inspection device: A stage on which the inspection object is placed; A photographing unit for photographing a test object placed on the stage; An illumination unit disposed to fix a relative position with respect to the photographing unit, and illuminating light to the inspection object; And It includes a linear movement unit for linearly moving the stage so that the relative position of the photographing unit and the inspection object is changed, The stage is A body having an upper space and an open space in a moving direction of the stage, on which the inspection object is placed; Combining with the body, and comprises a rolling member for supporting the edge of the photographing area of the inspection object to be photographed by the photographing unit, And the illumination unit is located in the space of the body when the body is positioned to face the imaging unit. The method of claim 11, The rolling member is A plurality of balls disposed at a predetermined interval in the space of the body and in contact with the bottom surface of the inspection object; And a bracket for supporting each of the balls, the bracket being coupled to the body. 13. The method of claim 12, The balls are And an optical inspection device arranged to be parallel to the moving direction of the stage. The method of claim 12, The optical inspection device It extends to penetrate the space of the body, further comprising a horizontal support disposed in the movement direction of the stage, The lighting unit When the stage is positioned to face the photographing unit, the illumination is installed on the horizontal support so as to be located in the space of the body, the transmission light for irradiating the transmitted light to the inspection object; And an illumination reflecting the reflected light to the inspection object. 13. The method of claim 12, The bracket is Optical inspection apparatus, characterized in that the height can be adjusted to change the relative distance between the inspection object and the ball.

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