JP2008164565A - Imaging unit, and visual inspection apparatus using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a visual inspection apparatus capable of coping with a large specimen without enlarging the device, and capable of replacing easily an imaging part or a light projection part even when it is troubled, and a visual inspection method using the same. <P>SOLUTION: The imaging unit 22 is stored with an imaging part 32 comprising at least one lens 32d for receiving a reflected light from the specimen 2 of an illumination light emitted linearly from the light projection part 32 onto a surface of the specimen 2 and for converging it, and a plurality of imaging elements 32c arranged linearly to image-focusing the light converged by the lens 32d, in a separable casing, and the plurality of imaging units 22 is connected while matched with a width dimension of the specimen 2 to constitute one connected imaging unit. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an imaging unit used for inspecting a subject such as a wafer substrate or a flat panel display (FPD) substrate, and an appearance inspection apparatus using the imaging unit.

  Conventionally, in the appearance inspection of a wafer substrate or the like (subject) that is smaller than the FPD substrate, the surface of the subject is irradiated with illumination light of a parallel light beam at a predetermined angle, and an image of the surface corresponding to the optical change of the reflected light The image is processed and image processing is performed to check for irregularities in the resist film applied to the surface, defects such as pinholes, and the presence or absence of dust adhesion.

  In recent years, for example, in a manufacturing process of a liquid crystal display which is a kind of FPD, a mother glass substrate capable of manufacturing a plurality of displays at once is used in order to improve productivity. Recently, a mother glass substrate having a length of one side exceeding 2000 mm and 3000 mm has appeared. This mother glass substrate has a substrate size that can efficiently produce various types of liquid crystal displays such as liquid crystal televisions and camera liquid crystal monitors. Appearance inspection apparatuses are required to support mother glass substrates of various sizes.

  As an appearance inspection apparatus corresponding to the appearance inspection of a large subject, for example, an apparatus 1 as shown in FIG. 19 has been proposed (see, for example, Patent Document 1). The appearance inspection apparatus 1 includes a base 4 provided with a stage unit 3 on which a subject 2 is placed, a portal-type column 5 upright on an upper surface 4 a of the base 4, and a base 4 on the tip 5 a of the column 5. And a support arm 6 extending in parallel with each other.

  The stage unit 3 is movable in one axial direction (for example, in the direction of the arrow a) along the upper surface 4a of the base 4, and the subject 2 placed on the stage unit 3 follows this.

  A light projecting unit 7 is attached to the support column 5 at substantially the center in the height direction. The light projecting unit 7 guides a light source (not shown) such as a halogen lamp and a light beam emitted from the light source. A fiber bundle not shown is a main component, and the fiber bundle is arranged in a direction perpendicular to the moving direction of the subject 2 (arrow a direction) within a range slightly longer than the width of the subject 2, and the surface of the subject 2 The light can be illuminated linearly.

  The support arm 6 includes a mirror 8a provided on the front end side, a line sensor camera (imaging device) 8b provided on the rear end side, and an imaging lens attached to the mirror 8a side of the line sensor camera 8b. 8c, and an interference filter 8d disposed between the mirror 8a and the imaging lens 8c. Here, the line sensor camera 8b and the imaging lens 8c are combined to form the imaging unit 8.

  In this configuration, the linear light beam (illumination light) irradiated to the surface of the subject 2 at the incident angle θ1 by the light projecting unit 7 is reflected at the reflection angle θ2 on the surface of the subject 2, and this reflected light is reflected by the mirror 8a. And is incident on the line sensor camera 8b through the interference filter 8d and the imaging lens 8c. As a result, a linear image of the surface of the subject 2 is captured by the line sensor camera 8b, and the image of the surface of the subject 2 is sequentially moved by moving the subject 2 at a constant speed in one axial direction by the stage unit 3. The image can be captured, and by processing the captured image, it is possible to inspect for the presence or absence of defects on the entire surface of the subject 2.

  In this appearance inspection apparatus 1, since the image of the entire surface of the subject 2 can be acquired by relatively moving the subject 2 and the appearance inspection apparatus 1 in one axial direction, it is possible to deal with a large subject 2. . Further, since the light beam (reflected light) reflected by the subject 2 is bent in a direction parallel to the subject 2 by the mirror 8a, the height can be kept low and the appearance inspection apparatus 1 can be miniaturized.

As an apparatus corresponding to the appearance inspection of a large subject, the apparatuses shown in FIGS. 20 to 21 have been proposed (see, for example, Patent Document 2). FIG. 20 shows the appearance inspection apparatus 10, and FIG. 21 is a view taken along line AA in FIG.
As shown in FIGS. 20 to 21, the appearance inspection apparatus 10 includes a light projecting unit 11 and an imaging unit 12, and illumination light is applied to the surface of the subject 2 from the light projecting unit 11 supported by appropriate means. The reflected light that is irradiated and reflected is received and imaged by the imaging unit 12 supported by appropriate means, and an image of the surface of the subject 2 is acquired. In addition, an image of the entire surface of the subject 2 is acquired by relatively moving the appearance inspection apparatus 10 and the subject 2 in one axial direction (direction of arrow a).

  The light projecting unit 11 includes a fiber bundle 11a in which two end faces 11b are arranged in a line and a cylindrical lens 11c spaced in parallel to the end face 11b.

  The imaging unit 12 includes a rod lens array (lens) 12a and a linear image sensor (imaging element) 12b. The rod lens array 12a receives reflected light of illumination light that is irradiated linearly on the surface of the subject 2. At the same time, this is condensed and an equal-magnification image of the irradiation area (imaging range) on the surface of the subject 2 is formed on the linear image sensor 12b.

  In this configuration, the linear illumination light emitted from the light projecting unit 11 is applied to the surface of the subject 2 at the incident angle θ1, and the reflected light reflected from the surface of the subject 2 enters the imaging unit 12 at the reflection angle θ2. Is done. As a result, the reflected light is captured and imaged by the linear image sensor 12b, and the subject 2 and the appearance inspection apparatus 10 are moved relative to each other at a constant speed in one axial direction of the subject 2, thereby sequentially subject 2 Image acquisition of the surface is performed, and the entire surface of the subject 2 can be inspected.

In this appearance inspection apparatus 10, an image of the entire surface of the subject 2 can be acquired by the relative movement of the subject 2, the light projecting unit 11, and the imaging unit 12, so that it is possible to deal with a large subject 2. Further, since the cylindrical lens 11c is used for the light projecting unit 11 and the rod lens array 12a is used for the imaging unit 12, the light projecting unit 11 and the imaging unit 12 can be brought close to the surface of the subject 2, and the apparatus 10 can be miniaturized.
JP 2000-266682 A JP-A-9-61365

 However, in the above-described appearance inspection apparatus, it is necessary to redesign the optical system instead of the light projecting unit and the imaging unit corresponding to the size of the mother glass substrate (subject), and there is a problem in the degree of freedom in design. In this way, if the optical design was redone each time according to the size of the subject, it would not only impose a heavy burden on productivity, but also need to have various members according to the size of the subject. There was a problem that a large burden was imposed on the economy from the nature.

  In addition, even when a problem occurs in the light projecting unit or the image capturing unit, if it is configured by one light projecting unit and one image capturing unit, a plurality of workers are required for the operation of removing and attaching them. In addition, in the FPD production line, since the bus line for conveying the mother glass substrate is as high as 1500 mm, it is difficult to replace the long light projecting portion of 2000 mm and 3000 mm.

 Further, when a large mother glass substrate is inspected by a pair of light projecting unit and image capturing unit, a long and narrow slit-like illumination region irradiated in the width direction of the subject, for example, an irradiation region having a length of 2000 mm, is collected. In order to take an image, a very long imaging distance is required as in Patent Document 1, and there is a problem that the appearance inspection apparatus is enlarged. In addition, when the imaging devices having the same resolution are used, there arises a problem that the detection accuracy is lowered because the image quality of the image taken by the imaging unit is lowered as the imaging separation from the subject becomes longer. .

  In addition, if the imaging lens is widened and the distance between the subject and the imaging unit is shortened in order to increase the detection accuracy for a large subject, the peripheral image is distorted with respect to the center of the imaging, which adversely affects defect detection. There is a fear.

In order to improve the yield of the production line, after applying a resist to the surface of the specimen, visual inspection is performed at the earliest possible stage, and if any abnormality is found, the result can be fed back to the production equipment. It has been demanded. For this reason, the appearance inspection apparatus is required to be directly connected to the production line as much as possible. However, in the conventional case, the appearance inspection apparatus cannot be incorporated into the manufacturing apparatus, and the appearance inspection apparatus has to be arranged on the downstream side of the developing device, which is the final manufacturing process of the manufacturing line. For this reason, when a defect occurs in the resist coating apparatus, which is the first manufacturing process, a large number of mother glass substrates are flowing in each manufacturing apparatus and in the transfer line between the manufacturing apparatuses. It takes a long time for the defective substrate to reach the inspection apparatus, making it impossible to respond quickly. When a defective substrate arrives at the appearance inspection apparatus, a large amount of defective substrates are caused to flow between the resist coating apparatus and the inspection apparatus, resulting in a problem that the manufacturing yield is lowered.
In addition, when a macro inspection device that captures an image of the entire surface of the mother glass substrate and a micro inspection device equipped with a microscope that observes in detail the defects detected by the macro inspection device are integrated into a composite inspection device, As shown in Patent Document 1, the macro inspection apparatus occupies a large space, and there arises a problem that the entire composite inspection apparatus is enlarged.

  In view of the above circumstances, the present invention can cope with a large subject without increasing the size of the apparatus, and an imaging unit that can be easily replaced even when a malfunction occurs in an imaging unit or a light projecting unit. An object of the present invention is to provide a visual inspection apparatus used.

  In order to achieve the above object, the present invention provides the following means.

  The imaging unit of the present invention includes at least one lens that illuminates illumination light linearly on the surface of the subject from the light projecting unit, receives reflected light from the subject of the illumination light, and collects the reflected light. An imaging unit including a separable housing having an imaging unit composed of a plurality of imaging elements arranged in a line to form an image of the light collected by the lens, and the imaging unit is connected to the subject. A plurality of units are connected in accordance with the width dimension to constitute one connected imaging unit.

  An appearance inspection apparatus according to the present invention includes a light projecting unit that irradiates a surface of a subject with linear illumination light, a lens that receives reflected light from the subject and collects the illumination light, An image pickup unit that receives and collects light collected by the lens, an image processing unit that processes an image formed by the image pickup unit, and the light projecting unit and the image pickup unit. In an appearance inspection apparatus including a stage unit that holds the subject so as to move relative to each other in one axis direction, illumination light is linearly irradiated from the light projecting unit to the surface of the subject, and the subject of the illumination light An image pickup unit comprising at least one lens that receives reflected light from the light and collects the light and a plurality of image pickup elements arranged in a line that forms an image of the light collected by the lens can be separated. The imaging unit is housed in a housing, and this imaging unit is connected to the width of the subject. Characterized by comprising a single coupling the imaging unit and a plurality linked in the law.

  According to the above invention, by providing a plurality of imaging units connected so as to be equal to or larger than the examination range of the subject, the examination range can be changed in size by a simple operation of connecting and removing the imaging unit. In addition, by moving the subject and the imaging unit relative to each other, a one-surface image of the subject surface can be reliably acquired. Accordingly, it is possible to flexibly cope with various sizes of subjects without changing the optical system, and it is possible to reduce the size of the appearance inspection apparatus and perform inspection in a small space.

  Hereinafter, an imaging unit and an appearance inspection apparatus according to a first embodiment of the present invention will be described with reference to FIGS.

  The first embodiment of the present invention relates to an appearance inspection apparatus that macroscopically inspects a surface of an object such as a semiconductor wafer substrate or a glass substrate for a flat panel display.

  The appearance inspection apparatus 20 shown in FIGS. 1 to 2 includes, for example, a stage unit 3 on which a subject 2 which is a mother glass substrate for manufacturing a plurality of liquid crystal displays, and the stage unit 3 in one axial direction (X direction). The base 4 is movably supported, and the connected imaging unit 21 is attached to the center of the base 4 in a direction (Y direction) orthogonal to the moving direction (X direction) of the stage unit 3.

  The base 4 is formed in a rectangular disk shape, and two raceways 4b and 4c for moving the stage portion 3 in the X direction are provided on the upper surface 4a. The two raceways 4b and 4c are the stage portions. 3 is provided in parallel from one end 4d to the other end 4e in the X direction of the base 4 so as to pass below the connected imaging unit 21. In addition, the base 4 has a width dimension H in the X direction of the base 4 and a width dimension T in the X direction of the connected imaging unit 21 added to a length twice the width dimension L in the X direction of the stage unit 3. It is formed to be larger than the dimensions.

  The stage portion 3 is formed in a rectangular plate shape, and connection blocks 3b are provided on both ends of the lower surface 3a in the X direction, and can be moved on the tracks 4b and 4c of the base 2 via the connection block 3b. Has been. The subject 2 is placed on the upper surface 3c.

  As shown in FIGS. 3 and 4, the coupled imaging unit 21 includes a plurality of imaging units 22 such that the total length C in the Y direction is longer than the width dimension B (length dimension in the Y direction) of the subject 2. Are connected. Further, L-shaped fixing brackets (fixing means) 23 are attached to both side surfaces 21 a and 21 b in the Y direction of the connected imaging unit 21. The fixing bracket 23 is attached by appropriate means, for example, a pin and a hole engaging with a fitting pin 30h and a fitting hole 30j, which will be described later in detail, formed in the imaging unit 22, respectively. The connected imaging unit 21 is configured to be held above the surface of the subject 2 so that the surface of the subject 2 and the lower surface of the connected imaging unit 21 do not come into contact with each other during the examination. Further, the fixing bracket 23 keeps the relative angle of the imaging element 32c, which will be described later, arranged on a straight line with respect to the subject 2 constant by connecting the imaging units 22 to each other.

As shown in FIG. 7, the imaging unit 22 includes a substantially concave housing 30 and a light projecting unit that irradiates the surface of the subject 2 attached along one inner wall of the housing 30 with linear illumination light. 31 and an imaging unit 32 that receives the reflected light reflected from the surface of the subject 2 and is imaged, which is attached to the other inner wall of the housing 30 facing the light projecting unit 31. An opening 30 a is formed below the housing 30, and the surface of the subject 2 is irradiated with irradiation light from the light projecting unit 31 by making the opening 30 a face the surface of the subject 2. The reflected light reflected by the imaging unit 32 can be received by the imaging unit 32. The imaging unit 32 is preferably capable of imaging an imaging range of 150 mm to 500 mm, for example, and has a short imaging distance. The imaging unit 32 determines the length A1 of the light projecting unit 31 and the length A2 of the imaging unit 22. In the case where the LED elements are linearly arranged in the light projecting unit 31, the LED elements can be arranged up to the end of the housing 30, and the length of the illumination range (imaging range) of the light projecting unit 32. A1 and the length A2 of the housing 30 can be made substantially the same length. In addition, the light emitted from each LED element of the light projecting unit 31 is formed into parallel line illumination light by the cylindrical lens 36, and the line illumination light of each LED element is slightly expanded so that the line illumination light of the adjacent LED element is Make sure they overlap each other. In the present embodiment, it is assumed that an imaging range of 40 mm can be captured, and the length A2 of the imaging unit 22 in the Y direction is set to 400 mm.
For example, when the length dimension in the Y direction of the subject 2 is 2000 mm, five imaging units 22 are connected, four are connected when the length is 1500 mm, and three are connected when the length is 1000 mm. It is possible to configure the connected imaging unit 21 suitable for each size.
The coupled imaging unit 21 is moved relative to the subject 2 in the X direction, and the image formed by the imaging unit 32 of each imaging unit 22 is connected by the image processing means 33, whereby the width dimension of the subject 2 is measured. The entire pattern area smaller than B can be imaged.

  The housing 30 is formed of a lightweight and excellent corrosion-resistant metal such as aluminum, and two engagements extending in the Y direction in parallel with the side walls 30c and 30d on the outer peripheral side of the upper wall 30b. A groove 34 is provided. Further, on the outer peripheral side of the both side wall portions 30c and 30d, a single engagement groove 35 extending in the Y direction is provided at the approximate center in the height direction (Z direction) in parallel with the upper wall portion 30b. ing. These engagement grooves 34 and 35 are formed in a T-shaped cross section. As shown in FIG. 10, for example, when connecting a plurality of image pickup units 22, the engagement grooves 34 and 35 are fitting members that integrate the image pickup units 22. It is used as an insertion groove, and is continuously provided from the front end 30e to the rear end 30f of the housing 30 as shown in FIGS.

  Further, the housing 30 is provided with three fitting pins 30h protruding in parallel with the side surface 30g on the front end portion 30e side and projecting perpendicularly to the side surface 30g, and on the side surface 30i on the rear end portion 30f side. A fitting hole 30j that engages with the fitting pin 30h is provided at a position opposed to the fitting pin 30h that protrudes from the side surface 30g on the distal end portion 30e side. Here, the fitting pin 30h has, for example, a cylindrical shape or a triangular prism shape, and the fitting hole 30j has a shape into which the fitting pin 30h can be fitted.

  Further, on the inner peripheral side of the housing 30, a mounting portion 31 b formed with fitting grooves 31 c for mounting both ends of a flat-plate-shaped light projecting portion holding member 31 a on which a light projecting portion 31 described later is held, and details Is provided with a mounting portion 32b formed with a fitting groove 31c for mounting a substantially arc-shaped imaging portion holding member 32a as viewed in the direction of the arrow Y, where the imaging portion 32 described later is held. The attachment portions 31b are provided on the side wall portion 30c side and the upper wall portion 30b, respectively, and are inclined so that the line-shaped openings of the respective fitting grooves 31c and 31c coincide. As for the attachment part 32b which attaches the both ends of the imaging part holding member 32a, the fitting groove is formed in the upper wall part 30b and the side wall part 30d, respectively.

  The light projecting unit 31 includes, for example, LED elements arranged in a line in the Y direction and those in which end faces of fiber bundles that guide a light beam from a light source are arranged in a line in the Y direction. In the present embodiment, an example using a line illumination light source in which LED elements are arranged in a line in the Y direction will be described. As shown in FIG. 7, a cylindrical lens 36 for shaping the light beam emitted from each LED element into a parallel light beam is attached to the emission side of the light projecting unit 31. The light projecting unit 31 is held by a light projecting unit holding member 31a, and both ends of the light projecting unit holding member 31a are fitted and fixed in fitting grooves 31c and 31c. At this time, the light projecting unit holding member 31a is fixed so that the linear illumination light emitted from the light projecting unit 31 is irradiated onto the surface of the subject 2 at a predetermined incident angle θ1. In addition, the width in the X direction of the irradiation range irradiated from the light projecting unit 31 to the surface of the subject 2 is slightly wider than the length in the X direction of the imaging region required by the imaging unit 32.

As shown in FIGS. 8 and 9, the imaging unit 32 condenses the reflected light reflected by the irradiation region, for example, an imaging lens 32 d such as a microlens or a cylindrical lens, and the reflection condensed by the imaging lens 32 d. It is comprised by the image pick-up element 32c which images light. Here, the image sensor 32c is arranged linearly in the Y direction. As shown in FIG. 7, the imaging unit 32 is held by an imaging unit holding member 32a, and both ends of the imaging unit holding member 32a are fitted into the fitting grooves of the mounting portions 32b and 32b and fixed. At this time, the reflected light reflected from the surface of the subject 2 at the reflection angle θ2 is fixed at a position where the reflected light can be reliably received, and the imaging range B in the Y direction captured by the imaging unit 32 is the length of the illumination range. The imaging distance is set to be approximately the same length as A1.
In the present embodiment, the imaging unit 32 is fixed at a position where the incident angle θ1 of the illumination light and the reflection angle θ2 are equal to capture regular reflection light (interference light) in the imaging range B reflected from the surface of the subject 2. Has been. When imaging the diffracted light from the subject 2, the imaging unit 32 may be fixed at a position where the reflection angle of the n-th order diffracted light is reflected, and the imaging unit is set at a position where the reflection angles of the interference light and the diffracted light are respectively reflected 32 may be fixed. It is also possible to arrange the image pickup device 32c as a two-dimensional curved surface as the image pickup unit 32 so that interference light and diffracted light can be simultaneously picked up by the image pickup device 32c arranged in a line in the Y direction.

  As shown in FIG. 10, the imaging unit 22 includes a fitting pin 30 h protruding from the side surface 30 g on the front end 30 e side of the housing 30, and a side surface 30 i on the rear end 30 f side of the other imaging unit 22. Can be connected by fitting into a fitting hole 30j provided in the plurality of image pickup units 22, whereby a plurality of image pickup units 22 can be connected to form a connected image pickup unit 21. Here, the adjacent image pickup units 22 are connected such that there is no overlapping portion in the images picked up by the respective image pickup units 22 and the images picked up by the image pickup units 22 are connected to obtain a one-line image. Further, by inserting fitting members into the engaging grooves 34 and 35 provided in the upper wall portion 30b and the both side wall portions 30c and 30d of the housing 30, the plurality of imaging units 22 are reliably integrated. The length of the integrated linked imaging unit 21 in the Y direction is such that a plurality of imaging units 22 having a length of 400 mm, for example, 5 in the case of 2000 mm, are linked according to the length dimension of the subject 2 in the Y direction. This can be easily adjusted.

  In addition, each imaging unit 22 is electrically connected when mechanically coupled, and is configured as one coupled imaging unit 21. As shown in FIG. 1, the coupled imaging unit 21 is electrically connected to an image processing unit 33 and a display unit 33a.

  Next, a method for inspecting the subject 2 using the appearance inspection apparatus 20 having the above-described configuration will be described with reference to FIGS.

  The subject 2 is placed on the upper surface 3c of the stage unit 3, and the stage unit 3 is moved along the tracks 4b and 4c at a constant speed in one axial direction (X direction) by a transport mechanism (not shown). When the distal end portion 2a of the subject 2 reaches the illumination area (imaging area) of the illumination light emitted from the light projecting unit 31 of each imaging unit 22 of the coupled imaging unit 21, the illumination area on the surface of the subject 2 becomes the imaging unit. 32. Since the subject 2 is moving at a constant speed with respect to the connected imaging unit 21, each imaging unit of the connected imaging unit 21 images the surface of the subject 2 at a predetermined pitch timing. When the rear end 2b passes through the imaging range B of the illumination light, the entire image of the subject 2 is captured. By attaching these line-shaped image data by the image processing means 33, a macro image of the entire surface of the subject 2 is acquired.

  The image data acquired by the plurality of imaging units 32 is sent to the image processing unit 33 to detect defects such as film irregularities, pattern defects, and scratches on the subject 2, and is displayed on the display unit 33a and displayed on the inspector. Is visually inspected.

  Therefore, according to the appearance inspection apparatus 20 described above, the optimum length for the size of the subject 2 is changed by changing the number of connected imaging units 22 according to the width dimension B of the subject 2 in the Y direction. In addition, the coupled imaging unit 21 can be easily configured, and the optical system can be flexibly handled without changing the design of the optical system. Further, even when a malfunction occurs in the imaging unit 32 or the light projecting unit 31, only the imaging unit 22 in which the malfunction has occurred can be removed and replaced, and maintenance can be easily performed. In addition, by setting the imaging unit 22 to a length of 150 mm to 500 mm that is easy for an operator to hold, the imaging unit 22 can be attached and detached by one person, and workability is improved.

  Further, according to the appearance inspection apparatus 20 described above, the imaging range of one imaging unit 32 can be reduced by setting the imaging range of the imaging unit 32 to 1 / n of the inspection range of the subject 2. The imaging distance between the subject 2 and the imaging unit 32 is shortened, the connected imaging unit 21 can be reduced in size, and the appearance inspection apparatus 20 can be reduced in size. As a result, it is possible to save the space occupied by the appearance inspection apparatus 20 and arrange it in the transport path between the manufacturing apparatuses of the manufacturing line, the specimen loading / unloading port of each manufacturing apparatus, and the manufacturing apparatus. It becomes possible. Therefore, since the subject 2 carried out from each manufacturing apparatus can be inspected, the cause of the defect generated in the manufacturing apparatus can be quickly identified, and the manufacturing process can be corrected quickly. And it is prevented that a lot of defective goods are put out, and it has a big advantage also economically. In addition, since the single image of the subject 2 can be acquired by the plurality of imaging units 32, an image having a resolution substantially proportional to the number of the imaging units 32 can be obtained, and the defect detection accuracy can be significantly improved. Here, when the image of the entire surface of the subject 2 is satisfied with the conventional resolution, the performance of the image sensor 32c can be reduced, and the cost of the appearance inspection apparatus 20 can be reduced.

  Further, according to the appearance inspection apparatus 20 described above, the connected imaging unit 21 is fixed by the fixing bracket (fixing means) 23, and the subject 2 is passed under the connected imaging unit 21, whereby the one-surface image of the subject 2 is obtained. Since it can be obtained, it can be incorporated into a production line and inspected using existing conveyance means. In this case, the appearance inspection apparatus 20 can be provided in a portion of the existing conveyance means that is not used for purposes other than conveyance, which greatly contributes to space saving.

  Next, an imaging unit and an appearance inspection apparatus according to a second embodiment of the present invention will be described with reference to FIGS.

  In the second embodiment of the present invention, the examination of the subject 2 is performed using the connected imaging unit 21 similar to that shown in FIGS. 3 to 10 shown in the first embodiment. In description of this embodiment, the same code | symbol is attached | subjected with respect to the structure which is common in the visual inspection apparatus 20 which concerns on 1st Embodiment, and description about a detail is abbreviate | omitted.

  11 to 12, the subject 2 is placed on the upper surface 3c of the stage unit 3 mounted at the center of the base 4, and in this case, the stage unit 3 is stationary. The subject 2 is placed on the stage unit 3 using, for example, a transport robot. The connected imaging unit 21 provided with the fixtures (fixing means) 23 on both side surfaces 21a and 21b is larger than the width dimension (examination range) of the subject 2 placed on the stage unit 3 as in the first embodiment. The imaging unit 22 is connected so as to be long, can be moved in one axial direction (X direction) of the subject 2, and can be irradiated with linear illumination light on the surface of the subject 2. Similarly to the first embodiment, the fixture 23 can hold the coupled imaging unit 21 above the surface of the subject 2 so that the surface of the subject 2 and the coupled imaging unit 21 do not come into contact with each other at the time of examination. ing. Further, the base 4 has a width H in the X direction of the base 4 obtained by adding a length twice as large as the width T in the X direction of the coupled imaging unit 21 to the width L in the X direction of the stage unit 3. It is formed to be larger than the dimensions.

  The coupled imaging unit 21 is movable on two base tracks 4b and 4c provided in parallel to the base 4 with the stage portion 3 therebetween. At this time, the connected imaging unit 21 has a fixed block 23a attached to the fixing bracket 23, and is installed on the tracks 4b and 4c via the fixed block 23. For example, the fixed block 23a is connected to driving means (not shown). Thus, the connected imaging unit 21 can be moved on the tracks 4b and 4c and moved at a constant speed.

  Therefore, according to the appearance inspection apparatus 40 described above, since the entire surface image of the subject 2 can be acquired by moving the connected imaging unit 21 instead of the subject 2, the same effect as the first embodiment can be obtained. Play.

  In addition, this invention is not limited to said 1st Embodiment and 2nd Embodiment, In the range which does not deviate from the meaning, it can change suitably. For example, in the above embodiment, the light projecting unit 31 and the image capturing unit 32 housed in the housing 30 of the image capturing unit 22 are held by the light projecting unit holding member 31a and the image capturing unit holding member 32a, respectively. The optical unit 31 and the imaging unit 32 may be directly fixed to the housing 30 with screws. Further, although the light projecting portion holding member 31a and the imaging portion holding member 32a are fitted and fixed in the fitting grooves, the fixing means is not particularly limited. Further, the T-shaped engaging grooves 34 and 35 formed in the upper wall portion 30b and the side wall portions 30c and 30d of the housing 30 are used when the fitting member is connected and integrated with each other. The dovetail groove is provided in the horizontal arm portion of the gantry, and the dovetail portion that fits into the dovetail groove is formed in the upper wall portion 30b of the housing 30 so that each imaging unit 22 can be attached and detached. You may make it provide.

  In the first and second embodiments described above, the imaging unit 22 collects the reflected light from the subject 2 on one housing 30 and the collected reflected light. Although one imaging unit 32 including a plurality of imaging elements 32c to form an image and one light projecting unit 31 are accommodated, the imaging unit 22 includes one imaging unit 32 as shown in FIGS. You may provide the some image pick-up part 32 comprised from the light projection part 31, the some lens 32d, and the some image pick-up element 32c corresponding to this. In this case, the imaging ranges of the adjacent lenses 32d in the imaging unit 22 do not overlap each other, and the captured images are connected as they are to obtain a one-plane image.

  Further, in the first embodiment and the second embodiment described above, the imaging unit 22 has a single lens 32d that condenses the reflected light on one housing 30, and a plurality of images that image the collected reflected light. Although one imaging unit 32 including the imaging element 32c and one light projecting unit 31 are accommodated, the imaging unit 22 reflects the reflected light from the subject 2 as shown in FIGS. Only one imaging unit 32 including one lens 32d that collects the light and a plurality of imaging elements 32c that forms an image of the collected reflected light may be housed in the housing 30. In this case, linear illumination light is irradiated to the surface of the subject 2 from the light projecting unit 31 separately provided outside the imaging unit 22, and the imaging unit 22 can receive the reflected light reflected from the surface of the subject 2. Thus, it is provided at a position where a predetermined imaging range can be imaged.

  Further, as shown in FIGS. 17 to 18, a single housing 30 of the imaging unit 22 that does not contain the light projecting unit 31 includes a plurality of lenses 32 d and a plurality of imaging elements 32 c corresponding to the respective lenses 32 d. A plurality of imaging units 32 including the above may be accommodated. In this case, the image pickup ranges B arranged by the adjacent lenses 32d in the image pickup unit 22 do not overlap with each other, and the picked-up images are connected as they are to obtain a single image.

1 is a plan view of an appearance inspection apparatus according to a first embodiment of the present invention. It is a side view of the external appearance inspection apparatus shown in FIG. It is a top view which shows the connection imaging unit of the external appearance inspection apparatus shown in FIG. FIG. 4 is a side view of the coupled imaging unit illustrated in FIG. 3. It is a top view which shows the imaging unit which concerns on this invention. FIG. 6 is a side view of the imaging unit shown in FIG. 5. It is sectional drawing of the imaging unit shown in FIG. It is a top view which shows the imaging state by the imaging unit shown in FIG. It is a side view of FIG. It is a perspective view which shows the connection state of the imaging unit shown in FIG. It is a top view of the external appearance inspection apparatus which concerns on 2nd Embodiment of this invention. It is a side view of the external appearance inspection apparatus shown in FIG. It is a top view which shows the imaging state by the imaging unit provided with the light projection part and the some imaging part. FIG. 14 is a side view of FIG. 13. It is a top view which shows the imaging state by the imaging unit which is not equipped with a light projection part. FIG. 16 is a side view of FIG. 15. It is a top view which shows the imaging state by the imaging unit provided with the several imaging part. It is a side view of FIG. It is a figure which shows the example of the conventional external appearance inspection apparatus. It is a figure which shows the example of the conventional external appearance inspection apparatus. It is the AA arrow directional view of the conventional external appearance inspection apparatus shown in FIG.

Explanation of symbols

2 Subject 3 Stage unit 4 Base 20 Appearance inspection device 21 Connected imaging unit 22 Imaging unit 23 Fixing bracket (fixing means)
30 Housing 31 Projecting Unit 32 Imaging Unit 32c Imaging Element 32d Lens 33 Image Processing Unit 40 Appearance Inspection Device

Claims (5)

  Illumination light is linearly irradiated from the light projecting unit to the surface of the subject, the reflected light of the illumination light from the subject is received, and is collected by the lens and at least one lens that collects the reflected light. The imaging unit is composed of a plurality of imaging elements arranged in a line to form the imaged light, and the imaging unit is housed in a separable casing, and a plurality of the imaging units are connected in accordance with the width dimension of the subject. An image pickup unit comprising a single connected image pickup unit. The imaging unit according to claim 1,
The imaging unit, wherein at least one of the light projecting units is housed in a linear shape in the housing. The imaging unit according to claim 1 or 2,
The said housing | casing is connected with the said other housing | casing so that each said image pick-up element may be distribute | arranged on a straight line. The imaging unit according to any one of claims 1 to 3,
An imaging unit, wherein a fixing means is provided on a side surface of the casing that intersects a straight line connecting the imaging elements so as to keep a relative angle of the imaging element with respect to the subject constant. A light projecting unit that irradiates the surface of the subject with linear illumination light, a lens that receives the reflected light from the subject and collects the illumination light, and light collected by the lens. An imaging unit that receives light and forms an image thereof, an image processing unit that processes an image formed by the imaging unit, and the subject in one axial direction with respect to the light projecting unit and the imaging unit In the visual inspection apparatus comprising a stage unit that holds the relative movement,
Illumination light is linearly irradiated from the light projecting unit to the surface of the subject, the reflected light of the illumination light from the subject is received, and is collected by the lens and at least one lens that collects the reflected light. The imaging unit is composed of a plurality of imaging elements arranged in a line to form the imaged light, and the imaging unit is housed in a separable casing, and a plurality of the imaging units are connected in accordance with the width dimension of the subject. An external appearance inspection apparatus comprising a single connected imaging unit.

Images