JP5373657B2 - Component mounting apparatus and component mounting method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a component-mounting apparatus that can measure the height of a substrate with a low-cost and space-saving configuration, and to provide a component mounting method. <P>SOLUTION: A substrate recognition camera 9 takes an image of a mark 30 based on light transmitting a half-mirror 100. Additionally, a laser light source 101 emits a laser beam L1 to the position of a substrate surface 3a, away from the image-taking position of the substrate recognition camera 9, in a direction perpendicular to the substrate surface 3a. Then, the light L2, which is the laser beam L1 reflected at an irradiated position 31, is guided by a prism 102 to the half-mirror 100 so as to be reflected by the half-mirror 100 and is guided to the substrate recognition camera 9, along the optical axis OA1 of the camera 9. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a component mounting apparatus and a component mounting method for mounting electronic components on a substrate.

  2. Description of the Related Art Conventionally, a component mounting apparatus has been known in which an electronic component is sucked from a component supply unit and mounted on a substrate positioned at a mounting work position by driving a movable head unit mounted with a component suction mounting head. ing. In this type of device, a board recognition camera is usually mounted on the head unit. The camera captures marks on the board and recognizes the position of the board in advance to ensure component mounting accuracy. I am doing so. In such a component mounting apparatus, if the height of the substrate fluctuates due to warpage of the substrate or the like, the mounting position of the component shifts in the vertical direction, making it difficult to mount the component suitably. Therefore, for example, in the apparatus described in Patent Document 1, a laser measuring instrument is installed in the head unit to measure the height of the substrate. For example, in the apparatus described in Patent Document 2, a light emitting device irradiates light on the substrate surface from an oblique direction to form a figure having a clear outline on the substrate surface, and the above-mentioned figure is obtained by a substrate recognition camera. Is measured to measure the height of the substrate.

Japanese Patent No. 3097262 (FIGS. 1 and 4) JP2003-298294A (FIGS. 4, 11, and 15)

  However, in the apparatus described in Patent Document 1, an expensive laser measuring instrument is installed in the head unit, which increases the cost. In addition, the mass and installation space of the head unit are increased by the amount of the laser measuring instrument, and the driving force required to drive the head unit is also increased.

  On the other hand, in the apparatus described in Patent Document 2, since the camera for substrate recognition is shared for measuring the height of the substrate, the problem as in Patent Document 1 does not occur from the viewpoint of cost and installation space. However, since light is emitted from the oblique direction to the substrate surface by the light emitting device, the following problems may occur.

  That is, as is clear from FIG. 11 of Patent Document 2, when the height of the substrate changes due to warpage of the substrate, the light irradiation position on the substrate surface also changes. Therefore, there are irregularities such as holes and mounted parts in the vicinity of the measurement position of the board height, and if the light irradiation position overlaps with this irregularity, the above figure cannot be captured clearly with the camera, so accurate height measurement Becomes difficult.

  Further, as shown in FIG. 15 of Patent Document 2, a configuration in which an imaging unit is installed so as to capture the above image from an oblique direction, and light is irradiated vertically from the light emitting device toward the substrate surface is also conceivable. In such a configuration, since the light irradiation position does not change even if the height of the substrate changes, the above problem can be avoided. However, since the imaging unit is installed so as to capture the above image from an oblique direction, this imaging unit cannot be shared with the substrate recognition camera, leading to an increase in cost and installation space.

  The present invention has been made in view of the above problems, and an object thereof is to provide a component mounting apparatus and a component mounting method capable of measuring the height of a substrate with a low-cost and space-saving configuration.

  A component mounting apparatus according to the present invention is a component mounting apparatus that mounts a component on a substrate by a mounting head that is movable relative to the substrate. In order to achieve the above object, a mark on the substrate surface is marked on the substrate surface. An imaging unit that captures an image from a direction perpendicular to the substrate, a light source that irradiates light perpendicularly to a position on the substrate surface that is distant from an imaging position on the substrate surface that is imaged by the imaging unit, and irradiates light on the substrate surface from the light source And a light guide unit that guides the reflected light reflected at the light irradiation position to the imaging unit and receives the reflected light by the imaging unit, and the substrate in a direction perpendicular to the substrate surface based on the reception result of the reflected light by the imaging unit It is characterized by measuring the height.

  A component mounting method according to the present invention is a component mounting method in which a component is mounted on a substrate by a mounting head that is relatively movable with respect to the substrate. A step of imaging by the imaging unit from a direction perpendicular to the substrate surface, a step of irradiating light perpendicular to the position of the substrate surface away from the imaging position of the substrate surface imaged by the imaging unit, and light on the substrate surface The step of guiding the reflected light reflected by the substrate surface to the imaging unit when it is irradiated and receiving the reflected light by the imaging unit, and the height of the substrate in the direction perpendicular to the substrate surface based on the result of receiving the reflected light by the imaging unit And a measuring step.

  In the invention configured as described above (component mounting apparatus and component mounting method), since the mark on the substrate surface is imaged from the direction perpendicular to the substrate surface by the imaging unit, the mark is suitably recognized by the imaging unit without hindrance. be able to. In addition, light is irradiated perpendicularly to the position on the substrate surface away from the imaging position on the substrate surface imaged by the imaging unit, and reflected light reflected on the substrate surface is guided to the imaging unit and received by the imaging unit. The height of the substrate in the direction perpendicular to the substrate surface is measured based on the result of receiving the reflected light by the imaging unit. Here, since light is irradiated perpendicularly to the substrate surface, even if the height of the substrate surface changes due to warpage of the substrate, the position where the light is irradiated on the substrate surface does not change. Therefore, the height of the substrate in the direction perpendicular to the substrate surface can be accurately measured. In addition, since the imaging unit can be shared for mark recognition and height measurement, it is possible to reduce the cost and space of the apparatus.

  Here, the light guide unit may be configured by combining a reflective optical member such as a reflection mirror. For example, the light emitted from the imaging position on the first optical path in which reflected light travels from the irradiation position to the imaging unit. May be configured to have a prism disposed at a position away from the second optical path going to the imaging unit. Further, the prism is made of a medium having a refractive index larger than that of the medium positioned in the second optical path, and the amount of reduction in the focal length due to the refractive index of the prism is equal to the geometric optical path length of the first optical path. It is desirable that the refractive index of the prism and the geometric optical path length of the optical path along which the reflected light travels in the prism are set so as to substantially match the difference from the geometric optical path length of the second optical path. That is, since the irradiation position is far from the imaging position, the geometric optical path lengths of the first optical path and the second optical path are different. However, when the prism set as described above is used, the optical focal lengths in the respective imaging units with respect to the irradiation position and the imaging position become substantially equal. Therefore, for example, by setting the distance between the imaging unit and the imaging position so that the imaging position is in focus, both the mark and the reflected light can be received appropriately, so both mark recognition and height measurement can be performed with high accuracy. Can be executed. That is, for example, when the geometric optical path lengths of the first optical path and the second optical path are different from each other and the distance between the imaging unit and the imaging position is set so that the imaging position is in focus, the reflected light is favorably received. In order to achieve this, it is necessary to move components such as the imaging unit and the light guide unit so that the irradiation position is in focus. However, according to the said structure, the movement of such a member becomes unnecessary.

  The light guide unit has a half mirror arranged on the optical axis of the imaging unit, guides the reflected light emitted from the irradiation position to the half mirror from the axis outside the optical axis of the imaging unit, It may be configured to guide the imaging unit along the optical axis. In this case, the imaging unit images the mark via the half mirror. In this configuration, for example, a configuration in which the imaging unit and the half mirror are arranged so that the mark is captured based on the light transmitted through the half mirror can be employed. In such a configuration, the reflected light emitted from the irradiation position is guided to the half mirror from outside the optical axis of the imaging unit, reflected by the half mirror, and guided to the imaging unit along the optical axis. What is necessary is just to comprise. Alternatively, for example, a configuration in which the imaging unit and the half mirror are arranged so that the mark is imaged based on the light reflected from the half mirror can be employed. In such a configuration, the reflected light emitted from the irradiation position is guided to the half mirror from outside the optical axis of the imaging unit, transmitted through the half mirror, and guided to the imaging unit along the optical axis. What is necessary is just to comprise. According to these configurations, it is possible to suitably perform both mark recognition and height measurement by the imaging unit without moving the light guide unit and the like. That is, when a half mirror is not provided, a configuration in which the light guide unit is disposed on the optical axis of the imaging unit and the reflected light emitted from the irradiation position is guided to the imaging unit along the optical axis can be considered. However, in this case, since the light guide unit interferes when the mark is imaged, a configuration in which the light guide unit is moved to a position away from the optical axis of the imaging unit is necessary. On the other hand, according to the said structure provided with a half mirror, since the structure which moves a light guide part is unnecessary, it is possible to aim at simplification of an apparatus structure.

  In addition, a shutter unit that can switch between guiding and blocking the reflected light to the half mirror in the optical path where the reflected light travels from the irradiation position to the half mirror, and a shutter drive control unit that switches the guidance and blocking of the reflected light by driving the shutter unit May be further provided. According to this configuration, when measuring the height of the substrate, the reflected light is transmitted through the half mirror by driving the shutter unit and switching the shutter unit so that the reflected light is guided to the half mirror. As a result, the height measurement of the substrate surface can be suitably performed. On the other hand, when imaging the mark, stray light is guided to the half mirror from the optical path where the reflected light travels from the irradiation position to the half mirror by driving the shutter unit and blocking the guidance of the reflected light to the half mirror by the shutter unit. Thus, it is possible to prevent the stray light from being guided to the imaging unit via the half mirror, and as a result, it is possible to perform mark recognition with high accuracy.

It is a top view which shows schematic structure of one Embodiment of the component mounting apparatus concerning this invention. It is a partial side view of the component mounting apparatus shown in FIG. It is a block diagram which shows the main electrical structures of the component mounting apparatus shown in FIG. It is a perspective view which shows the principal part of a measurement part. It is a side view which shows typically the principal part of a measurement part. It is a figure for demonstrating the geometric optical path length from each part to the light-receiving part of the camera for board | substrate recognition. It is a figure which shows the deformation | transformation form of a measurement part.

  FIG. 1 is a plan view showing a schematic configuration of an embodiment of a component mounting apparatus according to the present invention. FIG. 2 is a partial side view of the component mounting apparatus shown in FIG. FIG. 3 is a block diagram showing the main electrical configuration of the component mounting apparatus shown in FIG. In FIGS. 1 and 2 and the drawings described later, XYZ rectangular coordinate axes are shown in order to clarify the directional relationship between the drawings.

  In the component mounting apparatus 1, the board transport mechanism 2 is disposed on the base 11, and the board 3 can be transported in a predetermined transport direction X. More specifically, the substrate transport mechanism 2 has a pair of conveyors 21 and 21 that transport the substrate 3 from the right side to the left side of FIG. And the conveyors 21 and 21 carry in the board | substrate 3, make it stop in a predetermined mounting operation position (position of the board | substrate 3 shown to the same figure), and fix and hold | maintain the board | substrate 3 with a holding device not shown. Then, the electronic components supplied from the component supply unit 4 are transferred to the substrate 3 by the mounting head 61 mounted on the head unit 6. When the mounting process is completed for all the components to be mounted on the substrate 3, the substrate transport mechanism 2 unloads the substrate 3. A component recognition camera 7 is disposed on the base 11. The component recognition camera 7 includes an illumination unit, a CCD (Charge Coupled Device) camera, and the like, and picks up images of electronic components held by the mounting heads 61 of the head unit 6 from below. Yes.

  The component supply unit 4 described above is arranged on the front side (+ Y axis direction side) and the rear side (−Y axis direction side) of the substrate transport mechanism 2 configured as described above. These component supply units 4 include a number of tape feeders 41. Each tape feeder 41 is provided with a reel (not shown) around which a tape storing and holding electronic components is wound, so that the electronic components can be supplied to the head unit 6. In other words, each tape stores and holds small chip electronic components such as integrated circuits (ICs), transistors, and capacitors at predetermined intervals. Then, when the tape feeder 41 feeds the tape from the reel to the head unit 6 side, the electronic components in the tape are intermittently delivered, and as a result, the electronic components can be picked up by the mounting head 61 of the head unit 6. .

  The head unit 6 conveys electronic components to the substrate 3 while being held by suction by the mounting head 61, and transfers the electronic components to a position designated by the user. Then, a total of twelve mounting heads 61 including six mounting heads 61F arranged in a line in the X-axis direction on the front side and six mounting heads 61R arranged in a line in the X-axis direction on the rear side are arranged. Have. That is, as shown in FIGS. 1 and 2, in the head unit 6, six mounting heads 61F extending in the vertical direction Z are arranged at an equal pitch in the X-axis direction (the direction in which the substrate 3 is transferred by the substrate transfer mechanism 2). It is provided in a row. Further, a rear row configured in the same manner as the front row is provided on the rear side (−Y-axis direction side) with respect to the mounting head 61F. That is, six mounting heads 61 </ b> R extending in the vertical direction Z are provided in a row at an equal pitch in the X-axis direction.

  In addition, a suction nozzle 62 is attached to the tip of each mounting head 61. A negative pressure generator, a positive pressure generator, and the atmosphere are connected to each suction nozzle 62 via an electric switching valve (not shown). The control device 8 applies a negative pressure suction force from the negative pressure generator to the suction nozzle 62 so that the lower end portion (tip portion) of the suction nozzle 62 is an electronic component. Parts can be held by adsorbing the upper surface. Conversely, when a positive pressure from the positive pressure generator is supplied to the suction nozzle 62 by the control device 8, the suction and holding of the electronic component by the mounting head 61 is released, and the electronic component is instantaneously mounted on the substrate 3 by the positive pressure. . Then, after the electronic component is mounted, the suction nozzle 62 is opened to the atmosphere. As described above, in the head unit 6, the electronic component can be attached and detached by controlling the negative pressure adsorption force and the positive pressure supply by the control device 8.

  Each mounting head 61 can be moved up and down (moved in the Z-axis direction) with respect to the head unit 6 by a nozzle lifting / lowering drive mechanism (not shown) and rotated about the nozzle center axis by a nozzle rotation driving mechanism (not shown) (FIG. 2). In the R direction). Of these drive mechanisms, the nozzle raising / lowering drive mechanism raises and lowers the mounting head 61 between a lowered position when sucking or mounting and a raised position when carrying or imaging. On the other hand, the nozzle rotation driving mechanism is a mechanism for rotating the suction nozzle 62 as necessary, and the electronic component can be positioned in a predetermined R-axis direction during mounting by rotation driving. Each of these drive mechanisms is composed of a servo motor and a predetermined power transmission mechanism.

  Further, the head unit 6 transports the electronic components sucked by these mounting heads 61 between the component supply unit 4 and the substrate 3 and mounts them on the substrate 3, so that the X-axis direction over a predetermined range of the base 11. And in the Y-axis direction (direction orthogonal to the X-axis and Z-axis directions). That is, the head unit 6 is supported so as to be movable along the X axis with respect to the mounting head support member 63 extending in the X axis direction. Further, both ends of the mounting head support member 63 are supported by a fixed rail 64 in the Y-axis direction, and are movable along the fixed rail 64 in the Y-axis direction. The head unit 6 is driven in the X-axis direction by the X-axis servomotor 65 via the ball screw 66, and the mounting head support member 63 is driven in the Y-axis direction by the Y-axis servomotor 67 via the ball screw 68. Is done. As described above, the head unit 6 can transport the electronic component sucked by the mounting head 61 from the component supply unit 4 to the target position.

  In the present embodiment, in addition to imaging various marks (fiducial marks, bad marks, etc.) on the surface of the substrate 3, a measurement including the substrate recognition camera 9 is performed to measure the height of the substrate 3. The unit 10 is attached to the head unit 6. Hereinafter, the configuration and operation of the measurement unit 10 will be described with reference to FIGS. 3 to 6.

  FIG. 4 is a perspective view showing a main part of the measuring unit 10. FIG. 5 is a side view schematically showing the main part of the measuring unit 10. FIG. 6 is a diagram for explaining the geometric optical path length from each part to the light receiving part of the substrate recognition camera. For convenience, the illustration of the shutter portion is omitted in FIG. The substrate recognition camera 9 captures an image of the mark 30 on the substrate surface 3a of the substrate 3 positioned at the mounting work position from a direction Z perpendicular to the substrate surface 3a, and has a light receiving portion 91 made of, for example, a CCD. . The light receiving unit 91 is disposed to face the substrate surface 3a and receives light in a direction (Z direction) perpendicular to the substrate surface 3a. That is, the substrate recognition camera 9 is arranged so that the optical axis OA1 of the substrate recognition camera 9 is perpendicular to the substrate surface 3a.

  A half mirror 100 described later is disposed below the substrate recognition camera 9 (−Z direction side), and an annular illumination unit 92 is opposed to the substrate 3 below the half mirror 100 (−Z direction side). Is arranged. The annular illumination unit 92 is configured by arranging a plurality of LEDs (Light Emitting Diodes) 92b in an annular shape on a donut board-shaped wiring board 92a having a circular through hole formed in the center. A coaxial illumination unit 93 is disposed on the right side (−X direction) of the half mirror 100 in FIG. 4. The coaxial illumination unit 93 is configured by two-dimensionally arranging a plurality of LEDs 93b on a wiring board 93a. The wiring board 93a is attached to a transparent glass plate 93c, and light emitted from each LED 93b passes through the glass plate 93c and proceeds to the half mirror 100. Further, below the annular illumination portion 92 (on the −Z direction side), a disc-shaped diffusion plate 94 made of, for example, milky white glass and having a circular through hole formed in the center is disposed. And the illumination light from the coaxial illumination part 93 reflected by the half mirror 100 and the illumination light from the annular illumination part 92 are transmitted through the diffusion plate 94, and the substrate surface 3a is diffusely illuminated.

  The half mirror 100 is arranged on the optical axis OA1 of the substrate recognition camera 9 so that the mirror surface is inclined at approximately 45 degrees with respect to the optical axis OA1. With this configuration, in this embodiment, the substrate recognition camera 9 images the mark 30 based on the light that has passed through the annular illumination unit 92 and the through-holes of the diffusion plate 94 and transmitted through the half mirror 100. Thus, in the present embodiment, the board recognition camera 9 corresponds to the “imaging unit” of the present invention.

  The measurement unit 10 further includes a laser light source 101. The laser light source 101 irradiates the laser beam L1 perpendicularly to the position of the substrate surface 3a away from the imaging position 32 of the substrate surface 3a by the substrate recognition camera 9. The irradiation position 31 of the substrate surface 3a irradiated with the laser light L1 is set in advance in a flat region of the substrate 3, and may be one place or a plurality of places. The laser light L1 emitted from the laser light source 101 is collimated by the collimating lens 111 and irradiates the substrate surface 3a. Thus, in this embodiment, the laser light source 101 corresponds to the “light source” of the present invention.

  As shown in FIG. 5, a prism 102 is disposed on the right side (−X direction) of the laser light source 101. This prism 102 is formed by integrating a substantially quadrangular prism-shaped lower half 121 and a substantially triangular prism-shaped upper half 122, and has an incident surface 123 that faces the irradiation position 31 irradiated with the laser light L1. Yes. Then, the reflected light L2 obtained by reflecting the laser light L1 from the laser light source 101 at the irradiation position 31 enters the prism 102 via the incident surface 123 and goes straight. The reflected light L2 traveling straight in the prism 102 is totally reflected by the inclined surface 124 of the upper half 122 and guided to the end face 125 orthogonal to the X-axis direction. Exit toward The reflected light L2 emitted from the prism 102 is reflected by the half mirror 100 and received by the light receiving unit 91 of the substrate recognition camera 9. That is, the prism 102 guides the reflected light L2 emitted from the irradiation position 31 to the half mirror 100 from the off-axis of the optical axis OA1 of the substrate recognition camera 9. As described above, in the present embodiment, the half mirror 100 and the prism 102 constitute the “light guide unit” of the present invention.

  In this embodiment, the shutter portion 103 is a plate-like member painted in black, for example, and is a blocking position (a position indicated by a two-dot chain line in FIG. 5) on the optical path where the reflected light L2 travels from the end face 125 of the prism 102 to the half mirror 100. ) And a separated position (a position indicated by a solid line in FIG. 5) apart from the optical path. Then, when the drive unit 131 (FIG. 3) drives the shutter unit 103, the shutter unit 103 moves between the blocking position and the separation position.

  The control device 8 (FIG. 3) includes a drive control unit 84, an image processing unit 85, an illumination control unit 86, and a light source control unit 87 for controlling each unit of the measurement unit 10, and the operation of the entire component mounting apparatus 1. A main control unit 81 that performs overall control and a storage unit 82 that stores various processing programs and various data are connected to each other via a bus 83 so that signals can be exchanged. The main control unit 81 controls the drive control unit 84, the image processing unit 85, the illumination control unit 86, the light source control unit 87, and the like according to a processing program stored in advance in the storage unit 82. That is, when the mark 30 is imaged, the drive control unit 84 controls the drive unit 131 to move the shutter unit 103 to the blocking position (the position indicated by the two-dot chain line in FIG. 5) and the illumination control unit 86. The annular illumination unit 92 and the coaxial illumination unit 93 are turned on. The data received from the mark 30 illuminated by the annular illumination unit 92 and the coaxial illumination unit 93 through the half mirror 100 and received by the light receiving unit 91 is sent to the image processing unit 85, and the image processing unit 85 Image processing is performed to acquire an image of the mark 30.

  On the other hand, when measuring the height of the substrate 3 in the Z direction, the drive control unit 84 controls the drive unit 131 to move the shutter unit 103 to the separation position (the position indicated by the solid line in FIG. 5) and the light source. The control unit 87 turns on the laser light source 101 and emits the laser light L1. Then, the reflected light L 2 reflected at the irradiation position 31 and transmitted through the prism 102 is reflected by the half mirror 100 and received by the light receiving unit 91, and is sent to the image processing unit 85. Then, for example, the peak position of the amount of received light is obtained by the image processing unit 85, and the height of the substrate 3 is obtained based on the peak position. That is, the peak position of the received light amount when the substrate surface 3a is at the reference height H0 (position indicated by the solid line in FIG. 5) is obtained in advance as the reference position P0 and stored in the storage unit 82. When the height of the substrate 3 becomes a different value (position indicated by a broken line in FIG. 5) due to warpage of the substrate 3, the peak position P <b> 1 of the received light amount is shifted from the reference position P <b> 0 stored in the storage unit 82. The main control unit 81 obtains the height H1 of the substrate surface 3a based on the deviation amount. The main control unit 81 controls the movement of the head unit 6 while correcting the change from the reference height H0 of the height H1 of the substrate surface 3a to control the mounting of the electronic components on the substrate 3. Thus, in the present embodiment, the drive control unit 84 and the drive unit 131 constitute the “shutter drive control unit” of the present invention.

  Here, referring to FIG. 6, the geometrical optical path length of the first optical path in which the reflected light L2 travels from the irradiation position 31 to the light receiving unit 91 of the substrate recognition camera 9, and the substrate surface 3 a by the substrate recognition camera 9. The geometrical optical path length of the second optical path in which the light emitted from the imaging position 32 (mark 30 in FIG. 6) proceeds to the light receiving unit 91 of the substrate recognition camera 9 will be described.

The geometrical optical path length D1 of the first optical path in which the reflected light L2 travels from the irradiation position 31 on the substrate surface 3a to the light receiving unit 91 is:
D1 = d + c + b
It is represented by Here, the symbol d is the distance from the irradiation position 31 to the total reflection position on the inclined surface 124 of the prism 102, the symbol c is the distance from the total reflection position to the mirror surface of the half mirror 100, and the symbol b is the reflection of the half mirror 100. The distance from the position to the light receiving unit 91 is shown. On the other hand, the geometrical optical path length D2 of the second optical path in which the light emitted from the mark 30 travels to the light receiving unit 91 is
D2 = a + b
It is represented by Here, the symbol a indicates the distance from the mark 30 to the mirror surface of the half mirror 100. In this embodiment, as apparent from FIG. 6, since c + d> a, D1> D2. Therefore, considering only the geometrical optical path length, for example, when the substrate recognition camera 9 is arranged so that the mark 30 is in focus, the irradiation position 31 is not in focus and the reflected light L2 is favorably received. It becomes difficult.

However, in the present embodiment, the mark 30 and the reflected light L2 are preferably captured using the technique previously invented by the inventor of the present application (the technique described in Japanese Patent Laid-Open No. 2009-4448). It is composed. That is, as a medium constituting the prism 102, the second optical path in which light emitted from the imaging position 32 (the mark 30 in this embodiment) of the substrate surface 3a by the substrate recognition camera 9 travels to the light receiving unit 91 of the substrate recognition camera 9 is used. A medium having a refractive index N larger than the refractive index (about 1) of the medium (air in this embodiment) is employed. At this time, the reduction amount ΔD of the focal length due to the refractive index N of the prism 102 is
ΔD = Dp (1-1 / N)
It is represented by Here, the refractive index N of the prism 102 is N> 1. Reference sign Dp is the geometric optical path length of the optical path along which the reflected light L2 travels through the prism 102, and Dp = e + f as shown in FIG. And
D1−ΔD≈D2
The medium (refractive index N) constituting the prism 102 is selected so that the geometrical optical path length Dp of the optical path along which the reflected light L2 travels in the prism 102 is set. Accordingly, when the substrate recognition camera 9 is arranged so that the mark 30 is in focus, the irradiation position 31 is also in focus, and the mark 30 can be moved without moving the member such as the substrate recognition camera 9 or the prism 102. It is possible to suitably perform the imaging and the reception of the reflected light L2.

  As described above, according to the embodiment of the present invention, the mark 30 on the substrate surface 3a is imaged by the substrate recognition camera 9 from the direction perpendicular to the substrate surface 3a. And can be suitably recognized.

  Further, in the present embodiment, the laser light source 101 that irradiates the laser light L1 perpendicularly to the position of the substrate surface 3a away from the imaging position 32 of the substrate surface 3a by the substrate recognition camera 9, that is, the irradiation position 31, When the laser beam L1 is irradiated, the reflected light L2 reflected at the irradiation position 31 on the substrate surface 3a is guided to the substrate recognition camera 9 and received by the substrate recognition camera 9, and the substrate surface is based on the light reception result. The height of the substrate 3 in the direction Z perpendicular to 3a is measured. As described above, since the laser light source 101 irradiates the laser beam L1 perpendicularly to the substrate surface 3a, even if the height of the substrate surface 3a changes due to the warp of the substrate 3, the laser beam L1 on the substrate surface 3a. The irradiation position 31 irradiated with is not changed. Therefore, the height of the substrate 3 in the direction Z perpendicular to the substrate surface 3a can be accurately measured.

  Further, according to the present embodiment, since the board recognition camera 9 is shared for the recognition of the mark 30 and the height measurement of the board surface 3a, the component mounting apparatus 1 can be reduced in cost and space. It is possible.

  In the present embodiment, the light emitted from the imaging position 32 by the substrate recognition camera 9 travels to the substrate recognition camera 9 on the first optical path where the reflected light L2 travels from the irradiation position 31 to the substrate recognition camera 9. The prism 102 is disposed at a position away from the second optical path. Further, the prism 102 is made of a medium having a refractive index N larger than that of air, and the reduction amount ΔD of the focal length due to the refractive index N of the prism 102 is set to the geometrical optical path length D1 of the first optical path. The medium (refractive index N) of the prism 102 is selected so as to substantially match the difference with the geometrical optical path length D2 of the second optical path, and the geometrical path of the optical path along which the reflected light L2 travels in the prism 102 is selected. An optical path length Dp is set. With this setting, the optical focal lengths of the substrate recognition cameras 9 with respect to the irradiation position 31 and the imaging position 32 of the substrate recognition camera 9 are substantially equal. Therefore, when the substrate recognition camera 9 is arranged so that the mark 30 is in focus, the irradiation position 31 is also in focus, and the member of the mark 30 is not moved without moving the substrate recognition camera 9 or the prism 102. Imaging and reflected light L2 can be received favorably.

  In the present embodiment, the half mirror 100 is disposed on the optical axis OA1 of the substrate recognition camera 9, and the reflected light L2 emitted from the irradiation position 31 is halfway from the off-axis of the optical axis OA1 of the substrate recognition camera 9. It is guided to the mirror 100, reflected by the half mirror 100, and guided to the substrate recognition camera 9 along the optical axis OA1. The substrate recognition camera 9 captures an image of the mark 30 based on the light transmitted through the half mirror 100. Therefore, it is possible to suitably perform both mark recognition and height measurement by the substrate recognition camera 9 without moving the prism 102 or the like. That is, when the half mirror is not provided, the exit surface from which the reflected light L2 is emitted from the prism is arranged on the optical axis OA1 of the substrate recognition camera 9, and the reflected light L2 is used for substrate recognition along the optical axis OA1. A configuration for guiding the camera 9 is conceivable. However, in this case, the prism becomes a hindrance when the mark 30 is imaged. Therefore, a configuration is required in which the prism is moved to a position away from the optical axis OA1 of the substrate recognition camera 9. On the other hand, according to this embodiment provided with the half mirror 100, since the structure which moves the prism 102 is unnecessary, it is possible to attain simplification of an apparatus structure.

  Further, in the present embodiment, the shutter unit 103 and the drive unit 131 are provided, and guidance and blocking of the reflected light L2 to the half mirror 100 are switched in an optical path in which the reflected light L2 travels from the irradiation position 31 to the half mirror 100. That is, when measuring the height of the substrate surface 3 a, the shutter unit 103 is moved to the separated position so that the reflected light L <b> 2 is guided to the half mirror 100. Thus, the reflected light L2 is guided to the substrate recognition camera 9 through the half mirror 100, and the height measurement of the substrate surface 3a can be suitably performed. On the other hand, when imaging the mark 30, the stray light is guided to the half mirror 100 from the optical path along which the reflected light L <b> 2 travels from the irradiation position 31 to the half mirror 100 by moving the shutter unit 103 to the blocking position. Guide to the substrate recognition camera 9 through the half mirror 100 can be prevented. As a result, the mark 30 can be recognized with high accuracy.

  The present invention is not limited to the above-described embodiment, and various modifications other than those described above can be made without departing from the spirit of the present invention. For example, in the above-described embodiment, the single prism 102 is used, but the present invention is not limited to this. For example, as described in the above-mentioned publication (Japanese Patent Laid-Open No. 2009-4448), a plurality of prisms are used. A group may be used.

  In the above embodiment, the blocking position of the shutter unit 103 is set between the prism 102 and the half mirror 100. However, the present invention is not limited to this, and is set between the irradiation position 31 and the prism 102. Also good. In short, a blocking position is set on the optical path along which the reflected light L2 travels from the irradiation position 31 to the half mirror 100, and the substrate recognition camera 9 passes along the optical axis OA1 of the substrate recognition camera 9 via the half mirror 100. The guided stray light may be blocked.

  In the above embodiment, the mechanical shutter unit 103 is used to move between the blocking position and the separation position. However, the present invention is not limited to this. For example, an electronic device such as a liquid crystal that can switch between transmission and blocking of light. A shutter may be arranged on the optical path where the reflected light L2 travels from the irradiation position 31 to the half mirror 100 to switch between guiding and blocking the reflected light L2. Alternatively, for example, a cylindrical cover that covers the periphery of the half mirror 100, the annular illumination unit 92, and the coaxial illumination unit 93 is movably provided, and when the mark 30 is imaged, the periphery of the half mirror 100 or the like is covered with the cover, When measuring the thickness, the cover may be retracted from the periphery of the half mirror 100 or the like.

  Moreover, in the said embodiment, although the reflected light L2 is guided to the half mirror 100 using the prism 102, it is not restricted to this, A reflection mirror etc. may be used. However, when the prism 102 is used as in the above embodiment, as described above, when the substrate recognition camera 9 is arranged so that the mark 30 is in focus, the irradiation position 31 can also be in focus. For this reason, the above embodiment is more advantageous than the case of using a reflection mirror.

  Moreover, in the said embodiment, although the laser light source 101 is used as a light source, it is not restricted to this, For example, LED, a fluorescent lamp, etc. may be sufficient. That is, any substrate recognition camera 9 may be used as long as it can recognize the irradiation position 31 where the light emitted from the light source irradiates the substrate surface 3a. The shape of the spot formed at the irradiation position 31 by the light emitted from the light source may be any shape as long as the substrate recognition camera 9 can recognize the irradiation position 31 such as a circle, a rectangle, or a triangle. Good. In the above embodiment, the collimator lens 111 is used. However, if the substrate recognition camera 9 can recognize the irradiation position 31, the collimator lens 111 may not be used.

  In the above-described embodiment, the reflected light L2 emitted from the irradiation position 31 is reflected by the half mirror 100 and guided to the substrate recognition camera 9 along the optical axis OA1. Although the mark 30 is imaged based on the light transmitted through the mirror 100, the present invention is not limited to this. For example, the mark 30 may be configured as shown in FIG. That is, in FIG. 7, the substrate recognition camera 9 is disposed on the right side (−X direction) of the half mirror 100, and the coaxial illumination unit 93 is disposed above the half mirror 100. According to this embodiment, the reflected light L2 emitted from the irradiation position 31 passes through the half mirror 100 and is guided to the substrate recognition camera 9 along the optical axis OA1. Further, the substrate recognition camera 9 images the mark 30 based on the light reflected from the half mirror 100. Even in the form as shown in FIG. 7, it is possible to obtain the same effects as those in the above embodiment.

DESCRIPTION OF SYMBOLS 1 ... Component mounting apparatus 3 ... Board | substrate 3a ... Board | substrate surface 30 ... Mark 31 ... Irradiation position 8 ... Control apparatus 84 ... Drive control part (shutter drive control part)
9 ... Camera for substrate recognition (imaging part)
91. Light receiving part (imaging part) of substrate recognition camera
100: Half mirror (light guide part)
101: Laser light source (light source)
102 ... Prism (light guide)
103: Shutter unit 131: Drive unit (shutter drive control unit)

Claims (5)

In a component mounting apparatus for mounting a component on the substrate by a mounting head movable relative to the substrate,
An imaging unit for imaging a mark on the substrate surface from a direction perpendicular to the substrate surface;
A light source that irradiates light perpendicular to the position of the substrate surface away from the imaging position of the substrate surface imaged by the imaging unit;
A light guide unit that guides the reflected light reflected at the light irradiation position to the imaging unit when the surface of the substrate is irradiated with light from the light source, and causes the imaging unit to receive the reflected light.
A component mounting apparatus that measures the height of the substrate in a direction perpendicular to the substrate surface based on a result of receiving the reflected light by the imaging unit. The light guide unit is disposed on a first optical path where the reflected light travels from the irradiation position to the imaging unit and away from a second optical path where light emitted from the imaging position proceeds to the imaging unit Has a prism,
The prism is formed of a medium having a refractive index larger than that of the medium positioned in the second optical path, and the amount of reduction in focal length due to the refractive index of the prism is a geometric optical path of the first optical path. The refractive index of the prism and the geometric optical path length of the optical path through which the reflected light travels in the prism are set so as to substantially match the difference between the length and the geometric optical path length of the second optical path. The component mounting apparatus according to claim 1. The light guide unit includes a half mirror disposed on the optical axis of the imaging unit, and guides the reflected light emitted from the irradiation position to the half mirror from outside the optical axis of the imaging unit. And guided to the imaging unit along the optical axis through the half mirror,
The component mounting apparatus according to claim 1, wherein the imaging unit images the mark through the half mirror. A shutter part capable of switching between guiding and blocking the reflected light to the half mirror in an optical path along which the reflected light travels from the irradiation position to the half mirror;
The component mounting apparatus according to claim 3, further comprising: a shutter drive control unit that drives the shutter unit to switch between guiding and blocking the reflected light. In a component mounting method for mounting a component on the substrate by a mounting head movable relative to the substrate,
Imaging a mark on the substrate surface by an imaging unit from a direction perpendicular to the substrate surface;
Irradiating light perpendicularly to the position of the substrate surface away from the imaging position of the substrate surface imaged by the imaging unit;
Guiding the reflected light reflected by the substrate surface when the substrate surface is irradiated with light to the imaging unit and receiving the reflected light by the imaging unit;
And a step of measuring the height of the substrate in a direction perpendicular to the surface of the substrate based on a result of receiving the reflected light by the imaging unit.

Images