Optical unit, processing device, and processing method

Abstract

The present invention is an optical unit (1) that images a first member (P1) held by a head (4) and a second member (P2) held by a stage (5), when calculating the relative positions of the first member (P1) and the second member (P2), the optical unit (1) comprising a synthesis unit (3), a camera (11), and a camera lens (2).

Description

Optical unit, processing device and processing method

[0001] The present disclosure relates to an optical unit (optical system for positioning recognition) used when positioning two members relative to each other or when positioning a member relative to a processing location, a processing device such as a positioning device using the optical unit, and a processing method such as a positioning method.

[0002] Conventionally, when manufacturing electronic components, the position of components such as substrates or chip components is grasped using a positioning device composed of a camera, etc., and each component is positioned. In this process, the positional misalignment of each component is corrected based on the amount of misalignment recognized by the camera. However, when components around the optical unit in the equipment thermally expand and deform, the optical axis of the camera itself shifts, resulting in errors in the positional correction. Therefore, it was necessary to detect the thermal distortion using a separate camera or mechanism to detect changes in the field of view and perform the correction.

[0003] For example, Patent Document 1 discloses a positioning device capable of accurately positioning a first member held by a bonding head and a second member placed on a stage. The positioning device disclosed in Patent Document 1 includes a prism having a first reflecting surface and a second reflecting surface, a camera, and a computing device. When the prism is positioned between the bonding head and the stage, the first reflecting surface reflects light incident from the head side toward the camera side, and the second reflecting surface reflects light incident from the stage side toward the camera side. The camera captures camera images including a first image representing the bonding head side and a second image representing the stage side based on the light incident from the prism. The computing device determines the positions of the first and second members based on the camera images. The computing device also detects the intersection line between the first and second reflecting surfaces of the prism, which is the boundary between the first and second images, from the images and calculates the relative positions of the first and second images. With this configuration, even if the optical axis of the camera shifts due to thermal distortion or the like, the relative position between the first image and the second image can be accurately calculated, and the relative position between the first member and the second member can be accurately corrected.

[0004] International Publication No. 2023 / 079798

[0005] However, in recent years, there has been a demand for ultra-high precision positioning of 1 μm or less, but with conventional techniques, it has been difficult to position the first member and the second member with ultra-high precision of 1 μm or less.

[0006] In this regard, Patent Document 1 lists several solutions for correcting the upper and lower fields of view. For example, to accurately position the first member and the second member, it is important to accurately detect the relative positions of the first image and the second image. Patent Document 1 describes a method of folding back one of the first and second images based on the intersection line of two reflecting surfaces that corresponds to the boundary between the first and second images.

[0007] However, it is difficult to detect this reference intersection line with high accuracy using normal imaging. In other words, because the position of the intersection line between the two reflecting surfaces of the prism is in a location different from the focal position of the lens, when actually capturing an image, the image is blurred, and the reference intersection line itself cannot be detected with high resolution.

[0008] Furthermore, as described in Patent Document 1, it is possible to use a separate mirror to focus the lens on the intersection of the two reflecting surfaces of the prism. However, the unit capturing the upper and lower fields of view is configured as an optical unit incorporating a prism, a camera, a lens, and other components. Meanwhile, the optical unit containing the mirror for detecting the intersection must be a separate unit from the optical unit containing the camera. Therefore, when components constituting these multiple units and the intervening units, such as the camera or the unit that moves the mirror, thermally expand and deform, minute angular displacements occur in each of the multiple units, and these displacements contribute to the detection result of the intersection position as an error. As a result, the calculation result of the relative position between the first and second members is subject to this error. As a result, the relative position between the first and second members cannot be accurately corrected, resulting in reduced positioning accuracy.

[0009] Furthermore, when using a mirror for detecting intersection lines, the state of the equipment differs between the state in which the image is captured using the mirror for detecting intersection lines and the state in which the image is captured to detect the relative position of the first member and the second member. Therefore, these different states can cause distortions due to changes in the center of gravity of each unit in the equipment, which can lead to errors. As a result, these errors can also be added to the calculation results of the relative position of the first member and the second member.

[0010] Furthermore, because the focal position of the lens is located at the position of the first and second members, there are two reflective surfaces between them that branch the optical paths of the first and second images. Therefore, near the boundary between the first and second images, some of the light containing each image information is not reflected toward the camera, resulting in a loss of image information, reduced resolution, and darkness. Light from the opposite field of view is mixed and enters the lens. This results in a significant reduction in the resolution of the resulting image, such as a double image where the first and second images overlap. Furthermore, even when not near the boundary between the first and second images, the ratio of the light intensity between the first and second images varies depending on the image position. Therefore, even when capturing an object with uniform brightness, the resulting image will have a gradient in brightness, similar to a gradation. This is another factor that reduces positioning accuracy.

[0011] The present disclosure has been made to solve such problems, and aims to provide an optical unit, a processing device, a processing method, etc. that can position a first member and a second member with high precision.

[0012] In order to achieve the above-mentioned object, one aspect of the optical unit according to the present disclosure is an optical unit that images a first member held on a head and a second member held on a stage when calculating the relative position of the first member and the second member, and includes a light combining unit, a camera, and a camera lens, wherein the light combining unit has an optical element having at least two reflective surfaces and a pair of work side lenses, each composed of one or more lenses, and the optical elements are positioned so that the intersection line of the two reflective surfaces is located near the focal plane of the camera lens, and when imaging the first member and the second member, one of the pair of work side lenses is positioned between the optical element and the first member, and the other of the pair of work side lenses is positioned between the optical element and the second member.

[0013] Furthermore, one aspect of a processing device according to the present disclosure includes the above-described optical unit and a computing device, wherein the camera acquires an image including each of the first member and the second member, and the computing device calculates a correction amount for the relative position between the first member and the second member based on the image, and positions the first member and the second member based on this correction amount.

[0014] Furthermore, one aspect of the processing method according to the present disclosure is a processing method for positioning the first member and the second member using the optical unit, the processing method including the steps of: holding the first member with the head; and holding the second member on the stage; disposing the optical unit between the head and the stage, and then focusing light from the first member that has passed through one of the pair of work-side lenses, after which the light is reflected by one of the two reflective surfaces of the optical element, thereby forming an image of the first member on a focal plane of the camera lens; and focusing light from the second member that has passed through the other of the pair of work-side lenses, after which the light is reflected by the other of the two reflective surfaces of the optical element, thereby forming an image of the second member on the focal plane of the camera lens, thereby acquiring a composite image including a first image of the first member and a second image of the second member; calculating a boundary between the first image and the second image in the composite image by a computing device, and calculating a correction amount for the relative positions of the first member and the second member in the horizontal direction from the boundary; and correcting the positions of the first member and the second member based on the correction amount.

[0015] According to the present disclosure, the first member and the second member can be positioned with high precision.

[0016] FIG. 1 is a diagram showing the configuration of a processing device according to a first embodiment. FIG. 2 is an enlarged view of a boundary portion between a first reflecting surface and a second reflecting surface of a prism used in the processing device according to the first embodiment. FIG. 3 is a flowchart of a processing method according to the first embodiment. FIG. 4 is a diagram showing an example of a composite image acquired in step S3 of the processing method according to the first embodiment. FIG. 5A is a diagram showing an image acquired using specular reflection light in the positioning device disclosed in Patent Document 1. FIG. 5B is a diagram showing an image acquired using diffuse reflection light in the positioning device disclosed in Patent Document 1. FIG. 6 is a diagram showing a composite image acquired using the processing device according to the first embodiment. FIG. 7 is a diagram showing the configuration of a processing device according to a second embodiment. FIG. 8 is an enlarged view of a boundary portion between a first reflecting surface and a second reflecting surface of a prism used in the processing device according to the second embodiment. FIG. 9 is a diagram showing the configuration of a processing device according to a third embodiment. FIG. 10 is a diagram showing the configuration of a processing device according to a fourth embodiment.

[0017] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. Note that each of the embodiments described below represents a specific example of the present disclosure. Therefore, the numerical values, shapes, materials, components, component placement and connection configurations, steps (processes), and step order shown in the following embodiments are merely examples and are not intended to limit the present disclosure. Therefore, among the components in the following embodiments, components that are not described in the independent claims that represent the superordinate concept of the present disclosure will be described as optional components.

[0018] In addition, in this specification and the drawings, the X-axis, Y-axis, and Z-axis represent the three axes of a three-dimensional Cartesian coordinate system. The X-axis and Y-axis are perpendicular to each other and are also perpendicular to the Z-axis. In this embodiment, the Z-axis direction is the vertical direction. Note that each drawing is a schematic diagram and is not necessarily an exact illustration. Therefore, the scales and the like do not necessarily match in each drawing. In each drawing, substantially identical components are assigned the same reference numerals, and duplicate explanations are omitted or simplified.

[0019] Furthermore, in this specification, the terms "above," "up," "below," and "below" do not refer to the upward direction (vertically upward) and downward direction (vertically downward) in absolute spatial recognition, but are used as terms defined by a relative positional relationship based on the stacking order in a stacked configuration. Furthermore, the terms "above," "up," "below," and "below" are used not only when two components are arranged with a gap between them and another component is present between them, but also when two components are arranged in contact with each other.

[0020] First Embodiment First, the configuration of a processing apparatus 100 according to a first embodiment will be described with reference to Fig. 1. Fig. 1 is a diagram showing the configuration of the processing apparatus 100 according to the first embodiment.

[0021] In the following description, the stage 5 has a mounting surface that is a substantially horizontal surface on which the second member P2 can be placed, and the direction perpendicular to the mounting surface of the stage 5 is the Z-axis direction. The camera is installed substantially horizontally or at a slight angle from the horizontal, and the X-axis direction is the straight line obtained by projecting the optical axis of the camera 11 onto the horizontal surface. The Y-axis direction is perpendicular to both the Z-axis direction and the X-axis direction.

[0022] The processing apparatus 100 in this embodiment is a positioning apparatus that positions the first member P1 and the second member P2 when they are mated. As an example, the processing apparatus 100 is a component mounter. In this case, the first member P1 and the second member P2 are mounted components. The processing apparatus 100, which is a component mounter, accurately positions the first member P1 and the second member P2 and places the first member P1 on the second member P2 when mounting an electronic component, which is the first member P1 (first component), on a substrate, which is the second member P2 (second component). The first member P1 is, for example, a thin, rectangular electronic component. Note that the first member P1 and the second member P2 may also be referred to simply as "workpieces." In this case, the term "workpieces" may refer to either the first member P1 or the second member P2, or both the first member P1 and the second member P2.

[0023] The processing apparatus 100 is not limited to a component mounter. For example, the processing apparatus 100 may be an apparatus that processes a first member P1 by pressing it as a mold against a precise position on a second member P2. The present disclosure is applicable to any apparatus that requires precise positioning of the first member P1 and the second member P2. For example, the first member P1 may be an imprint mold having a concave-convex structure, the second member P2 may be a workpiece to be imprinted, and the processing apparatus 100 may be an imprint apparatus that presses the first member P1 against the second member P2 at a precise position. Furthermore, the processing apparatus 100 may not be a processing apparatus such as an imprint apparatus, but may be an inspection apparatus that uses the first member P1 as an inspection probe, the second member P2 as an electronic component, and precisely positions the first member P1 against a small electrode or the like on the second member P2.

[0024] <Structure of Processing Apparatus> As shown in FIG. 1, a processing apparatus 100 according to this embodiment includes an optical unit 1, a head 4, a stage 5, a computing device 6, a display device 7, and a calibration jig stage 8.

[0025] The optical unit 1 can capture images of the first member P1 and the second member P2 when calculating the relative position between the first member P1 held by the head 4 and the second member P2 held by the stage 5. Therefore, when capturing images of the first member P1 and the second member P2, the optical unit 1 is disposed between the head 4 and the stage 5. Specifically, the head 4 and the stage 5 are disposed in a substantially vertical direction, and the optical unit 1 is disposed between the head 4 and the stage 5. Furthermore, the head 4 and the calibration jig stage 8 can also be disposed in a substantially vertical direction, and the optical unit 1 can also be disposed between the head 4 and the calibration jig stage 8.

[0026] The optical unit 1 includes a camera 11 having an imaging element, a camera lens 2, a light combining unit 3, and an optical unit holder 10 that integrally holds these. The optical unit holder 10 is, for example, a housing that holds the camera 11, the camera lens 2, and the light combining unit 3. The optical unit 1 is configured to be movable in horizontal directions (X-axis direction and Y-axis direction) by a drive unit (not shown).

[0027] The camera 11 sequentially or simultaneously captures a first image A1 obtained from the field of view (upper field of view) on the first member P1 side, a second image A2 obtained from the field of view (lower field of view) on the second member P2 side, and a third image A3 obtained by a reflecting surface boundary 31d (described later). This allows a composite image A including the first image A1, the second image A2, and the third image A3 to be obtained. In this case, the camera 11 may capture the composite image A including the first image A1, the second image A2, and the third image A3 as a single image, or the first image A1, the second image A2, and the third image A3 captured by the camera 11 may be combined by the computing device 6 to form a single composite image A.

[0028] The first image A1 is an image including the reference mark M1 (first member reference mark) of the first member P1, the second image A2 is an image including the reference mark M2 (second member reference mark) of the second member P2, and the third image A3 is an image including the field of view boundary line A0, which is the boundary line between the first image A1 and the second image A2.

[0029] In this embodiment, the camera 11 is a camera that can recognize an upper field of view (first field of view) and a lower field of view (second field of view), and can simultaneously capture an image of a first member P1 located above and a second member P2 located below to obtain an image that includes both the first member P1 and the second member P2. In other words, the optical unit 1 can use the camera 11 to capture a single composite image A that includes a first image A1 that includes the first member P1 and a second image A2 that includes the second member P2.

[0030] The camera 11 is configured to be able to capture an image of the focal plane 21 of the camera lens 2. The camera lens 2 is an optical system that focuses light on the imaging element of the camera 11 and is composed of one or more lenses. A coaxial illuminator 22 is arranged in the camera lens 2, which can irradiate the workpiece with light that is coaxial with the camera optical axis. The camera lens 2 is arranged so that the lens optical axis is inclined by an angle θ from the horizontal plane H. In other words, the camera optical axis of the camera 11 is inclined by an angle θ from the horizontal plane H. The coaxial illuminator 22 is an illumination device that irradiates light parallel to the camera optical axis of the camera 11. The coaxial illuminator 22 irradiates light (coaxial light) when the camera 11 images the workpiece.

[0031] The light combining unit 3 has a prism 31 which is an example of an optical element, a pair of work side lenses 32, a prism backlight 33, and an oblique light 34.

[0032] The prism 31 has a plurality of surfaces including at least two reflecting surfaces. The prism 31 having two reflecting surfaces has a structure in which, for example, a reflecting film such as a metal film is formed on the surface of a transparent substrate, but is not limited to this.

[0033] The prism 31 has two reflecting surfaces, a first reflecting surface 31a and a second reflecting surface 31b. The first reflecting surface 31a and the second reflecting surface 31b separate the upper and lower fields of view. Specifically, the first reflecting surface 31a is the upper reflecting surface corresponding to the upper field of view. The second reflecting surface 31b is the lower reflecting surface corresponding to the lower field of view.

[0034] In this embodiment, the first reflecting surface 31a and the second reflecting surface 31b are flat surfaces. The angle between the first reflecting surface 31a and the second reflecting surface 31b is a substantially right angle, specifically 90°. In this case, if the angle between the first reflecting surface 31a and the horizontal plane H is defined as angle φ1, then angle φ1 is expressed using the above-mentioned angle θ. Specifically, φ1 = 45° - θ / 2. Similarly, if the angle between the second reflecting surface 31b and the horizontal plane H is defined as angle φ2, then φ2 = 45° + θ / 2.

[0035] The first reflecting surface 31a and the second reflecting surface 31b intersect at a reflecting surface intersection line 31c. The reflecting surface intersection line 31c is the boundary line when the first reflecting surface 31a and the second reflecting surface 31b intersect. Here, the vicinity of the boundary between the first reflecting surface 31a and the second reflecting surface 31b will be described using Figure 2. Figure 2 is an enlarged view of the boundary between the first reflecting surface 31a and the second reflecting surface 31b in the prism 31.

[0036] As shown in FIG. 2 , the boundary between the first reflecting surface 31a and the second reflecting surface 31b of the prism 31 is not strictly a perfect right angle, but has a slight corner or a rounded shape. Therefore, the first reflecting surface 31a and the second reflecting surface 31b do not actually intersect, and a reflecting surface boundary 31d having a slight width exists at the boundary between the first reflecting surface 31a and the second reflecting surface 31b of the prism 31. As an example, the reflecting surface boundary 31d is a flat surface, but this is not limited thereto. Due to the presence of the reflecting surface boundary 31d in the prism 31, the composite image A obtained when the first member P1 and the second member P2 are captured by the camera 11 includes a third image A3 including a field of view boundary A0, which is the boundary between the first image A1 and the second image A2. The field of view boundary A0 is the original boundary between the first image A1 and the second image A2 when the reflecting surface boundary 31d does not exist in the prism 31.

[0037] The prism 31 is disposed so that a reflection surface intersection line 31c, which is the intersection line between the first reflection surface 31a and the second reflection surface 31b, is located near the focal plane 21 of the camera lens 2. Specifically, the prism 31 is disposed so that the reflection surface intersection line 31c and the reflection surface boundary 31d, which are located on the horizontal plane H, substantially coincide with the focal plane 21 of the camera lens 2.

[0038] In this embodiment, the reflecting surface boundary 31d of the prism 31 has a structure that transmits light. For example, by processing the prism 31, which has a reflecting film formed on the entire surface, to partially remove the reflecting film, it is possible to form the reflecting surface boundary 31d that has a small surface width and transmits light.

[0039] Because the reflective surface boundary 31d of the prism 31 transmits light, when the camera 11 captures an image with the prism back-illumination 33, which is located on the opposite side of the prism 31 from the camera lens 2 side, turned on, some or all of the light emitted from the prism back-illumination 33 (i.e., light emitted from the side of the prism 31 opposite the camera lens 2 side) is transmitted toward the camera lens 2 near the reflective surface intersection line 31c, which is the intersection line between the first reflective surface 31a and the second reflective surface 31b. This allows the reflective surface boundary 31d to be clearly imaged. In other words, the reflective surface boundary 31d can be clearly imaged using the light emitted from the prism back-illumination 33. The prism back-illumination 33 is an example of an illumination device that emits light, and it need only be located in a position where it can emit light from the opposite side of the prism 31 from the camera lens 2 side.

[0040] Furthermore, the angle of the surface of the reflective surface boundary 31d does not necessarily have to be perpendicular to the optical axis. By tilting the surface of the reflective surface boundary 31d with respect to the optical axis 20 of the camera lens 2 as shown in Figure 2, it is no longer necessary to reflect the specularly reflected light of the coaxial lighting 22 onto the camera lens 2 when using the coaxial lighting 22. This eliminates the need to balance the brightness of the workpiece and the brightness of the specularly reflected light from the reflective surface boundary 31d when imaging the workpiece, thereby improving the degree of freedom in adjusting the light irradiated onto the workpiece.

[0041] The pair of workpiece-side lenses 32 are disposed between the prism 31 and the first and second members P1 and P2 when capturing images of the first and second members P1 and P2.

[0042] The pair of work side lenses 32 is composed of a first work side lens 32a and a second work side lens 32b. Specifically, one of the pair of work side lenses 32 is the first work side lens 32a, and the other of the pair of work side lenses 32 is the second work side lens 32b. The first work side lens 32a is disposed above the prism 31, and the second work side lens 32b is disposed below the prism 31. In other words, the prism 31 is disposed between the first work side lens 32a and the second work side lens 32b. Specifically, the first work side lens 32a faces the first reflecting surface 31a of the prism 31, and the second work side lens 32b faces the second reflecting surface 31b of the prism 31. The first work side lens 32a and the second work side lens 32b are disposed so that their optical axes substantially coincide.

[0043] When the optical unit 1 is positioned between the first member P1 held by the head 4 and the second member P2 held by the stage 5 (i.e., when imaging the first member P1 and the second member P2), the first work side lens 32a is positioned between the first member P1 and the prism 31, and the second work side lens 32b is positioned between the second member P2 and the prism 31.

[0044] In addition, the pair of work side lenses 32 are positioned so that when the optical unit 1 is placed between the first member P1 held by the head 4 and the second member P2 held by the stage 5, the imaging surfaces of the first member P1 and the second member P2 are imaged on the focal plane 21 of the camera lens 2.

[0045] Specifically, the imaging surface of the first member P1 is a surface having the reference mark M1 of the first member P1, and the first workpiece side lens 32a is disposed so that the imaging surface of the first member P1 is imaged on the focal plane 21 of the camera lens 2. In other words, the first workpiece side lens 32a collects light from the first member P1 and images it on the focal plane 21 of the camera lens 2.

[0046] The imaging surface of the second member P2 is a surface having the reference mark M2 of the second member P2, and the second work-side lens 32b is disposed so that the imaging surface of the second member P2 is imaged on the focal plane 21 of the camera lens 2. In other words, the second work-side lens 32b collects light from the second member P2 and images it on the focal plane 21 of the camera lens 2.

[0047] The positions of the first workpiece side lens 32a and the second workpiece side lens 32b may be slightly deviated from the above positions as long as the image of the reflective surface boundary 31d is clear. For example, the positions of the first workpiece side lens 32a and the second workpiece side lens 32b may be within the depth of field of the camera lens 2.

[0048] Each of the pair of workpiece-side lenses 32 preferably has one or more telecentric lenses that are telecentric with respect to the workpiece side. Specifically, the first workpiece-side lens 32a may be configured as a telecentric lens that is telecentric on the first member P1 side. Similarly, the second workpiece-side lens 32b may be configured as a telecentric lens that is telecentric on the second member P2 side.

[0049] If the pair of work-side lenses 32 are non-telecentric optical systems with respect to the work side and the work is a specularly reflective material such as a wafer, there is a possibility that reflected light will not return to the camera lens 2 in areas where the optical axis of the coaxial lighting 22 is not perpendicular to the work. In this case, the image obtained will be bright only in the area where the light from the coaxial lighting 22 is irradiated perpendicularly to the work, i.e., near the optical axis, and dark in other areas. Therefore, in order to obtain a bright and clear image over a wide area, it is desirable that the pair of work-side lenses 32 be optical systems that are telecentric with respect to the work side. Of course, as long as the image resolution is within an acceptable range, the pair of work-side lenses 32 do not have to be optical systems that are telecentric with respect to the work side.

[0050] 1, each of the pair of work-side lenses 32 is illustrated as if it were composed of a single lens, but each of the pair of work-side lenses 32 may be composed of multiple lenses instead of a single lens. In other words, each of the pair of work-side lenses 32 may be a single lens or a lens group composed of multiple lenses. Furthermore, the first reflecting surface 31a and the second reflecting surface 31b of the prism 31 may not be flat, but may be the concave surfaces of a concave mirror. In this way, the first reflecting surface 31a and the second reflecting surface 31b will fulfill all or part of the role of the pair of work-side lenses 32.

[0051] The oblique illuminator 34 is an illumination device that irradiates light from an oblique direction with respect to the optical axis of the camera 11. That is, the oblique illuminator 34 irradiates light onto the workpiece at an angle with respect to the optical axis of the camera 11 when imaging the workpiece. The oblique illuminators 34 are disposed on both the first member P1 side and the second member P2 side. The oblique illuminator 34 on the first member P1 side irradiates light toward the first member P1 from an oblique direction with respect to the optical axis of the camera 11 (i.e., the optical axis of the first workpiece side lens 32a) when imaging the first member P1. The oblique illuminator 34 on the second member P2 side irradiates light toward the second member P2 from an oblique direction with respect to the optical axis of the camera 11 (i.e., the optical axis of the second workpiece side lens 32b) when imaging the second member P2.

[0052] The coaxial lighting 22 and the oblique lighting 34 may be turned on as appropriate depending on the surface condition of the workpiece. In other words, the workpiece may be imaged by appropriately irradiating the light of the coaxial lighting 22 and the oblique lighting 34 onto the workpiece. For example, if it is necessary to specularly reflect light from the workpiece, the coaxial lighting 22 mounted on the camera lens 2 may be turned on. On the other hand, if it is necessary to diffusely reflect light from the workpiece, the oblique lighting 34 may be turned on.

[0053] The head 4 can hold the first member P1. Specifically, the head 4 has a member holding surface on its underside that holds a member, and can hold the first member P1 on the member holding surface. The means for holding the first member P1 is not particularly limited, and various means such as suction or screw fastening are possible. In this embodiment, the head 4 holds the first member P1 by suction.

[0054] The stage 5 is capable of holding the second member P2. Specifically, the stage 5 is capable of holding the second member P2 on its upper surface. In other words, the second member P2 is placed on the upper surface of the stage 5. As with the head 4, the means by which the stage 5 holds the second member P2 is not particularly limited, and various means such as suction, holding, or placement are possible. In this embodiment, the stage 5 holds the second member P2 by suction.

[0055] The head 4 can be placed above the stage 5. The head 4 and the stage 5 are configured to be relatively movable. Specifically, the relative positions of the head 4 and the stage 5 in the horizontal direction can be changed. The head 4 and the stage 5 can also move closer to each other. Specifically, the relative positions of the head 4 and the stage 5 in the vertical direction can be changed to move closer to or farther away from each other.

[0056] The head 4 and the stage 5 may be configured so that only one of them is movable, or so that both are movable. In this embodiment, the head 4 and the stage 5 are configured so that both are movable. Specifically, the head 4 can move in the vertical direction (Z-axis direction). The stage 5 can move in the vertical direction (Z-axis direction) and horizontal directions (X-axis direction and Y-axis direction). The stage 5 can also rotate around the Z-axis. Therefore, although not shown, the processing device 100 has a drive unit that can move the head 4 in the Z-axis direction and a drive unit that can move the stage 5 in the X-axis direction, Y-axis direction, and Z-axis direction and rotate it around the Z-axis. The head 4 may also be configured so that it can rotate around the Z-axis, and so that it can move in the horizontal direction (X-axis direction and Y-axis direction).

[0057] The image captured by the camera 11 is output to the calculation device 6. Specifically, by using the camera 11 to capture images of the first member P1 held by the head 4 and the second member P2 held by the stage 5, it is possible to capture a composite image A including a first image A1 including the reference mark M1 of the first member P1 and a second image A2 including the reference mark M2 of the second member P2, and the composite image A is output to the calculation device 6. In this embodiment, the composite image A also includes a third image A3 of the boundary portion between the first image A1 and the second image A2.

[0058] The calculation device 6 is composed of a computer system or the like, and issues commands to each device in the processing device 100 (for example, commands to operate or stop the head 4 or stage 5, commands to capture images for the camera 11, output to the display device 7, etc.), and performs calculations from the obtained data.

[0059] For example, the calculation device 6 calculates a correction amount for the relative position between the first member P1 and the second member P2 based on the composite image A obtained by capturing an image with the camera 11, and positions the first member P1 and the second member P2 based on this correction amount. Specifically, the calculation device 6 extracts feature points of the first member P1 and the second member P2 from the composite image A, accurately calculates the boundary between the first image A1 and the second image A2 in the composite image A from the reflection plane intersection line 31c corresponding to the field of view boundary line A0 included in the composite image A, calculates the relative positions of the first member P1 and the second member P2 based on this boundary, thereby calculating a correction amount for the relative positions of the first member P1 and the second member P2, and moves the head 4 and the stage 5 based on this correction amount to accurately position the first member P1 and the second member P2.

[0060] 1, the captured composite image A may be output to a display device 7. That is, the composite image A may be displayed on the display device 7. The display device 7 is, for example, a display or a monitor.

[0061] The calibration jig stage 8 holds the calibration jig 81. Specifically, the calibration jig stage 8 is capable of holding the calibration jig 81 on its upper surface. In other words, the calibration jig 81 is placed on the upper surface of the calibration jig stage 8.

[0062] The calibration jig 81 placed on the calibration jig stage 8 is a thin plate-like object, and has a mark that can be imaged by the camera 11. The mark on the calibration jig 81 should be one that can be seen as the same from above and below. For example, the calibration jig 81 may be a transparent substrate such as glass, with the calibration jig mark M3 provided on one side thereof.

[0063] The calculation device 6 calculates the amount of correction for the relative position between the field of view position on the upper side (first member P1) and the lower side (second member P2) based on the image of the calibration jig 81 captured on the upper side (first member P1 side) and the image of the calibration jig 81 captured on the lower side (second member P2 side). In other words, the calculation device 6 calculates the amount of correction for the upper and lower reference positions of the field of view.

[0064] In this embodiment, the calibration jig mark M3 affixed to the calibration jig 81 is a thin film formed on a transparent substrate so that the same shape can be accurately seen from above and below, but this is not limited to this. The calibration jig mark M3 may be a hole or the like as long as it can be seen from above and below with appropriate accuracy. The shape, material, or number of the calibration jig marks M3 are also not particularly limited. The calibration jig 81 does not have to be placed on the calibration jig stage 8 as long as it is positioned so that it can be held by the head 4. In this embodiment, the calibration jig stage 8 and the calibration jig 81 are permanently installed in the facility, but they do not necessarily have to be permanently installed in the facility. In this case, the calibration jig 81 may be placed on the stage 5 when using the calibration jig 81.

[0065] <Processing Method (Operation of Processing Apparatus)> Next, a processing method using the processing apparatus 100 will be described using Fig. 3 while referring to Figs. 1 and 2. Fig. 3 is a flowchart of the processing method according to the first embodiment. That is, Fig. 3 shows the operation flow of the processing method using the processing apparatus 100.

[0066] The processing method according to this embodiment is a processing method for positioning the first member P1 and the second member P2 using the optical unit 1, and includes the following steps S1 to S8.

[0067] (Step S1: Calibration) First, calibration is performed on the processing device 100. Specifically, the calibration jig 81 is used to calculate the correction amount of the vertical reference positions of the field of view in the processing device 100 (step S1).

[0068] In this case, first, the calibration jig 81 is held by the head 4, and the head 4 is raised. As described above, the calibration jig 81 does not need to be permanently installed inside the processing device 100, but in this case, it is necessary to make it possible for the calibration jig 81 to be held by the head 4, for example by placing it on the stage 5 in advance.

[0069] Next, the optical unit 1 is placed above the calibration jig 81, and a first calibration image is obtained by capturing an image of the calibration jig 81 from above. Specifically, the head 4 is moved so that the optical unit 1 is below the calibration jig 81, and the first calibration image is obtained by capturing an image of the calibration jig mark M3 on the calibration jig 81 from below using the upper field of view of the optical unit 1. As an example, if the calibration jig mark M3 is a two-point circular mark, the midpoint between the centers of the two circular marks is set as the reference point of the upper field of view, and the straight line connecting the centers of the two points is set as the reference angle of the upper field of view.

[0070] Next, the optical unit 1 is placed below the calibration jig 81, and a second calibration image is obtained by capturing an image of the calibration jig 81 from below. Specifically, after retracting the optical unit 1, the head 4 is lowered and the calibration jig 81 is placed on the stage 5. The head 4 is then raised, and the optical unit 1 is returned to the position where the calibration jig mark M3 was captured. The calibration jig mark M3 is then captured in the lower field of view, thereby capturing the second calibration image. Furthermore, the reference point and reference angle in the lower field of view are calculated in the same manner as for the upper field of view.

[0071] The calculation device 6 then calculates the amount of correction for the vertical reference position of the field of view based on the difference between the reference points of the upper and lower fields of view and the difference between the reference angles of the upper and lower fields of view. The calculated amount of correction for the vertical reference position of the field of view can be added to the amount of correction for the relative position between the first member P1 and the second member P2 in step S4, which will be described later.

[0072] When calculating the correction amount for the vertical reference position of the field of view, correction using the reference point is essential, but correction using the reference angle is optional. Correction using the reference angle can be used or not depending on the required accuracy.

[0073] The frequency of calibration using the calibration jig 81 may be appropriately adjusted depending on the required accuracy. For example, calibration may be performed only once immediately after the installation of the processing apparatus 100, or may be performed after each component mounting, after a certain number of executions, or after a certain time has elapsed.

[0074] (Step S2: Work Setting) Next, the workpiece is set in the processing device 100 (step S2). Specifically, the first member P1 is held by the head 4, and the second member P2 is held by the stage 5. More specifically, the first member P1 and the second member P2 are supplied to the processing device 100 by a supply head (not shown), and the first member P1 is held by the head 4, and the second member P2 is held by the stage 5. At this time, a reference mark M1 used for alignment is marked on the surface of the first member P1, and a reference mark M2 used for alignment is marked on the surface of the second member P2. The reference mark M1 is located in a position that can be seen from below, and the reference mark M2 is located in a position that can be seen from above.

[0075] In this embodiment, the second member P2 is held in step S2, but this is not limiting. For example, if a plurality of small first members P1 are placed on a large second member P2, when the second or subsequent first members P1 are placed on the second member P2, the second members P2 are already held on the stage 5, so only the first members P1 are held by the head 4.

[0076] (Step S3: Imaging of Workpiece and Detection of Field Boundary Line) Next, in order to image the workpiece and calculate the relative positions of the upper and lower fields of view, the reflection surface intersection line 31c corresponding to the field of view boundary line A0 on the composite image A is detected (step S3).

[0077] First, the optical unit 1 is placed between the head 4 and the stage 5. That is, the optical unit 1 is placed between the first member P1 held by the head 4 and the second member P2 held by the stage 5. Specifically, the first member P1 and the second member P2 are placed one above the other with their horizontal positions approximately aligned, and then the optical unit 1 is placed at a position midway between the first member P1 and the second member P2.

[0078] Then, the light from the first member P1 that has passed through the first work side lens 32a is reflected by the first reflecting surface 31a of the prism 31 and then focused, thereby forming an image of the imaging surface of the first member P1 on the focal plane 21 of the camera lens 2, and the light from the second member P2 that has passed through the second work side lens 32b is reflected by the second reflecting surface 31b of the prism 31 and then focused, thereby forming an image of the imaging surface of the second member P2 on the focal plane 21 of the camera lens 2, thereby obtaining a composite image A that includes the first image A1, the second image A2, and the third image A3.

[0079] Specifically, by capturing an image of the reference mark M1 of the first member P1, the reference mark M2 of the second member P2, and the reflective surface boundary 31d with the camera 11, a composite image A is obtained that includes a first image A1 including the reference mark M1, a second image A2 including the reference mark M2, and a third image A3 including the field of view boundary line A0.

[0080] The reference mark M1 of the first member P1, the reference mark M2 of the second member P2, and the reflecting surface boundary 31d may be captured simultaneously as a single image, or as multiple separate images. That is, the first image A1 including the reference mark M1, the second image A2 including the reference mark M2, and the third image A3 including the field of view boundary line A0 may be captured simultaneously as a single composite image A, or may be a combination of multiple separately captured images. For example, if the imaging conditions are incompatible, such as adjusting one of the imaging conditions, such as the lighting or the shutter speed of the camera 11, to darken the others, separate images may be captured to suit the respective conditions. In this case, the composite image A can be obtained by combining the multiple images.

[0081] Furthermore, the third image A3 corresponding to the reflective surface boundary 31d can be captured more clearly by turning on the prism back illumination 33. That is, by transmitting part or all of the light irradiated from the surface of the prism 31 opposite the camera lens 2 side near the intersection line of the two reflective surfaces of the prism 31 and capturing the light with the camera 11 to obtain the third image A3, a clear third image A3 with high resolution can be obtained.

[0082] The calculation device 6 calculates a reflecting surface boundary 31d corresponding to the boundary portion between the first image A1 corresponding to the upper field of view and the second image A2 corresponding to the lower field of view in the third image A3.

[0083] It should be noted that, although the reflecting surface boundary 31d needs to be detected in order to calculate the relative position between the upper and lower fields of view, it does not necessarily have to be detected as a line as in this embodiment. For example, light-transmitting portions may be formed in the prism 31 so that the reflecting surface intersection line 31c can be detected as points or areas near both ends of the field of view, and the reflecting surface intersection line 31c may be calculated from the light that passes through the transmitting portions. In this case, the position, number, or shape of the transmitting portions is not particularly limited, and it is sufficient that the reflecting surface boundary 31d can be used as a reference for calculating the relative position between the upper and lower fields of view.

[0084] Furthermore, the detection of the reflection surface intersection line 31c is performed for the purpose of detecting and correcting the misalignment of the optical axis, which gradually changes due to thermal distortion caused by temperature changes within the optical unit 1, and does not necessarily have to be performed every time. It may be performed once for several mountings. Reducing the frequency of the detection can improve productivity. Furthermore, if noise occurs each time the workpiece is imaged, the accuracy of alignment may be improved by taking multiple images and averaging the results to reduce the effect of noise.

[0085] Furthermore, for the purpose of improving productivity, the reflection surface intersection line 31c may be detected by the optical unit 1 alone before the first member P1 and the second member P2 are placed in their predetermined positions.

[0086] Furthermore, as described above, it is most desirable that the reference mark M1 of the first member P1 and the reference mark M2 of the second member P2 are positioned so that they are vertically aligned, and that both the reference mark M1 and the reference mark M2 can be imaged without moving the optical unit 1. However, if either the reference mark M1 or the reference mark M2 is not within the imaging field of the camera 11, the optical unit 1 may be moved to sequentially image the reference mark M1 and the reference mark M2. In this case, correction may be made taking into account the amount of movement of the optical unit 1.

[0087] Furthermore, when the sizes of the first member P1 and the second member P2 are large, there may be multiple reference marks M1 on the first member P1 and multiple reference marks M2 on the second member P2. In this case, the relative positions of the reference marks M1 and M2 may be calculated for each of the multiple points on the reference marks M1 and M2, and the relative positions of the first member P1 and the second member P2 may be calculated based on the calculation results.

[0088] (Step S4: Calculation of correction amount for relative position) The composite image A acquired in step S3 is output to the calculation device 6, and the calculation device 6 calculates the correction amount for the relative position of the first member P1 and the second member P2 based on this composite image A (step S4).

[0089] Specifically, in step S4, for the composite image A acquired in step S3, the calculation device 6 calculates the boundary between the first image A1 and the second image A2 in the composite image A, and calculates the amount of correction for the relative position in the horizontal direction between the first member P1 and the second member P2 from the boundary. A specific method for calculating the amount of correction for the relative position will be described in detail below with reference to Fig. 4. Fig. 4 is a diagram showing an example of the composite image A acquired in step S3.

[0090] 4, composite image A includes a first image A1 including reference mark M1 on first member P1, a second image A2 including reference mark M2 on second member P2, and a third image A3 corresponding to reflection surface boundary 31 d. In this embodiment, first image A1 including reference mark M1, second image A2 including reference mark M2, and third image A3 including reflection surface boundary 31 d are captured as a single composite image A, but as described above, multiple images may be captured under different imaging conditions, and the position correction amount may be calculated based on the coordinates of the captured images in the following procedure.

[0091] First, the calculation device 6 calculates the field of view boundary line A0, which is the boundary between the first image A1 and the second image A2, from the obtained composite image A. In this embodiment, the field of view boundary line A0 corresponds to the reflection surface intersection line 31c, which is the intersection line between the first reflection surface 31a and the second reflection surface 31b of the prism 31. Therefore, the field of view boundary line A0 can be calculated by detecting the reflection surface intersection line 31c. In this embodiment, to detect the reflection surface intersection line 31c, as described above, the reflection surface boundary 31d, which is a surface that transmits light with a small width, is formed on the prism 31. The reflection surface intersection line 31c can be detected by capturing an image of the reflection surface boundary 31d. When capturing an image of the reflection surface boundary 31d, it is preferable to irradiate it with light from the prism back illumination 33 adjusted to an appropriate illuminance. This allows the light from the prism back illumination 33 to pass through the reflection surface boundary 31d, allowing an image of the reflection surface boundary 31d to be captured with high resolution. Furthermore, in this embodiment, since the reflecting surface boundary 31d is disposed near the focal plane 21 of the camera lens 2, the reflecting surface boundary 31d can be imaged with even higher resolution.

[0092] Then, the field of view boundary line A0 is obtained from the captured image of the reflecting surface boundary 31d. In this embodiment, a straight line at the center of the reflecting surface boundary 31d is calculated and used as the field of view boundary line A0. In this case, for example, a method can be considered in which a straight line is calculated that detects the edge of the reflecting surface boundary 31d on the first image A1 side, and a straight line is calculated that detects the edge of the reflecting surface boundary 31d on the second image A2 side, and the midline of these two straight lines is used as the field of view boundary line A0.

[0093] Note that the method for calculating the field of view boundary line A0 is not limited to this method. In addition, in this embodiment, the midlines of both sides of the reflecting surface boundary line 31d are set as the field of view boundary line A0, but this itself also depends on the shape of the reflecting surface boundary line 31d, and the method for calculating the field of view boundary line A0 itself is not particularly limited in the present disclosure.

[0094] Next, after calculating the field of view boundary line A0, the reference position N1 (first member reference position) of the first member P1 is calculated from the reference mark M1 of the first member P1, and the reference position N2 of the second member P2 is calculated from the reference mark M2 (second member reference position) of the second member P2. In this embodiment, the shape of each of the reference marks M1 and M2 is square. In this case, first, the four sides of the square are detected by image processing, and the positions of the four vertices are calculated from these four sides. Then, the positions of the centers of gravity of these four vertices can be set as the reference positions N1 and N2.

[0095] In addition to the reference positions N1 and N2, a reference angle may also be detected. In this case, the angle of the side closest to the field of view boundary line A0 among the four sides of the square with respect to the field of view boundary line A0 can be set as the reference angle.

[0096] The shape, quantity, and detailed calculation method of the reference marks M1 and M2 are not particularly limited as long as they are appropriately designed according to the workpiece. Furthermore, the reference marks M1 and M2 may be composed of multiple marks instead of a single mark. In this case, multiple marks may be detected, and their center of gravity positions may be used as the reference positions, and their main axis directions may be used as the reference angles, etc.

[0097] Next, the calculated reference position N1 is projected into the second image A2. In this case, the point where the reference position N1 is projected by folding back at the field of view boundary line A0 is set as the projection reference position N1'. This allows the relative position to be calculated correctly even if the camera 11 and lens are tilted in a direction that rotates relative to the optical axis due to thermal distortion or the like. Note that FIG. 4 is a diagram showing the case where the camera 11 is rotating about the optical axis. At this time, in order to correct the error between the detected reflecting surface boundary 31d and the calculated field of view boundary line A0, a fine correction calculation such as adding an offset from past data may be performed. Furthermore, the method for calculating the projection reference position N1' is not limited to the above method.

[0098] Next, in the second image A2, a correction amount D1 is calculated from the difference between the calculated reference position N2 and the calculated projection reference position N1'. This correction amount D1 is the correction amount for the relative position in the horizontal direction between the first member P1 and the second member P2. Note that the actual correction amount for this relative position may be obtained by adding other correction amounts and / or various offsets to this correction amount D1 as appropriate. For example, the correction amount for the relative position between the first member P1 and the second member P2 may be calculated by adding the correction amount for the vertical reference position of the field of view calculated in step S1 to the correction amount D1.

[0099] In this embodiment, the correction amount D1 is calculated by folding back the reference position N1 calculated using the reference mark M1 of the first member P1 at the field of view boundary line A0 and projecting it onto the second image A2, but this is not limited to this. For example, the reference position N2 may be calculated based on the reference mark M2 of the second member P2, and the point obtained by folding back this reference position N2 at the field of view boundary line A0 and projecting it onto the first image A1 may be set as the projection reference position N2'. The correction amount D2 may be calculated from the difference between the reference position N1 and the projection reference position N2', and this correction amount D2 may be used as the correction amount for the relative positions of the first member P1 and the second member P2 in the horizontal direction.

[0100] (Step S5: Determining Whether Position Correction is Necessary) Next, the calculation device 6 determines whether position correction is necessary (step S5). Specifically, a criterion for position correction is set in advance, and if the correction amount D1 calculated in step S4 does not satisfy the criterion, it determines that position correction is necessary (Yes in step S5) and performs position correction (step S6). On the other hand, if the correction amount D1 satisfies the criterion, it determines that position correction is not necessary (No in step S5) and proceeds to the mounting operation (step S7).

[0101] (Step S6: Position Correction Operation) If it is determined in step S5 that position correction is necessary, the calculation device 6 performs position correction of the first member P1 and the second member P2 based on the correction amount D1 calculated in step S4 (step S6).

[0102] This position correction is performed based on the correction amount D1 for the horizontal positions of the head 4 and stage 5. Thereafter, in order to recalculate the correction amount, the process may be repeated from step S3. If recalculation of the correction amount is not necessary, the position correction of step S6 is performed, and then the process moves to the next mounting operation (step S7).

[0103] (Step S7: Mounting Operation) Next, the mounting operation is performed (step S7). Specifically, after the optical unit 1 is retracted so as not to come into contact with the head 4 and the stage 5, the head 4 is brought close to the stage 5, and the first member P1 and the second member P2 are brought into contact with each other. Next, the first member P1 is separated from the head 4, and the first member P1 is placed on the second member P2 and bonded to each other. Methods for bonding the first member P1 and the second member P2 include, but are not limited to, heat and pressure bonding or solder bonding.

[0104] (Step S8: Mounting of Next Workpiece) After the first member P1 has been mounted on the second member P2, the head 4 is moved away from the stage 5, and the calculation device 6 determines whether or not to mount the next workpiece.

[0105] Specifically, if it is determined that the next first member P1 needs to be mounted (Yes in step S8), the process returns to step S2, the head 4 is moved to the component supply position to hold the next first member P1, and the stage 5 is moved to the next mounting position. At this time, if calibration is to be performed again, it may be performed from step S1.

[0106] On the other hand, if it is determined that the next mounting of the first member P1 is not necessary (No in step S8), one process ends. In this case, the optical unit 1, the head 4, the stage 5, etc. each perform the next action, such as moving in preparation for the next mounting operation.

[0107] In this embodiment, the head 4 is moved to bring it closer to the stage 5, but if the operation narrows the relative positions of the head 4 and the stage 5, the stage 5 may be moved to bring it closer to the head 4, or both the head 4 and the stage 5 may be moved to bring it closer to the head 4.

[0108] In the present embodiment, the processing apparatus 100 is a component mounter, and therefore the first member P1 is placed on the second member P2 and bonded to the second member P2. However, this is not a limitation. That is, the processing method is a mounting method in which the first member P1 is placed on the second member P2 and bonded to the second member P2. However, this is not a limitation. For example, if the processing apparatus 100 is an imprinting apparatus, the first member P1 is held by the head 4 as an imprint mold, accurately positioned using a method similar to the present embodiment, and then pressed against the second member P2 to apply pressure. After processing the second member P2, the head 4 is released along with the first member P1. Furthermore, if the processing apparatus 100 is an inspection apparatus or the like that requires a probe to be accurately pressed against an electrode of a minute test piece, the first member P1 can be held by the head 4 as a probe, accurately positioned relative to the second member P2 (the test piece), and then inspected after the first member P1 is brought into contact with the second member P2. The processing method may be a manufacturing method for electronic or optical components, or may be an inspection method for electronic or optical components.

[0109] (Effects, etc.) Next, the effects of the processing apparatus 100 using the optical unit 1 according to the first embodiment will be described with reference to FIGS. 5A, 5B, and 6. FIG.

[0110] The image on the right side of FIG. 5A shows a first image A1 (upper half of the image) and a second image A2 (lower half of the image) captured by the positioning device disclosed in Patent Document 1. The first image A1 is an image of two small solid circular marks attached as reference marks M1 on the first member P1. The second image A2 is an image of a large hollow circular mark attached as reference mark M2 on the second member P2. These marks are made of a transparent glass substrate with a mirror film formed on it. The first image A1 and the second image A2 were obtained by irradiating these marks with light coaxial with the camera optical axis and capturing the specularly reflected light reflected by the marks with a top and bottom view recognition camera. In FIG. 5A, the image on the right side shows the entire captured image, and the image on the left side shows an enlarged view of the left mark in the second image A2.

[0111] 5A, the boundary between the first image A1 and the second image A2 can only be determined from the slight gradation in the background, making it difficult to detect the boundary between the first image A1 and the second image A2 with high accuracy. Therefore, as described in Patent Document 1, an optical unit having a mirror for detecting the intersection line is required.

[0112] However, as mentioned above, the optical unit having the mirror for detecting the intersection line may be affected by thermal distortion, which may result in an error in the calculation of the upper and lower field of view positions.

[0113] Moreover, as can be seen from the enlarged image on the left side of Figure 5A, the image becomes darker near the boundary between the first image A1 and the second image A2 (the upper part of the image on the left side of Figure 5A), and the resolution is also lower.

[0114] FIG. 5B also shows an image of a test piece in which the irradiated light is diffusely reflected rather than specularly reflected by a mirror surface. The image in FIG. 5B was captured by irradiating the test piece with light at an angle relative to the camera's optical axis and capturing the diffusely reflected light from the test piece. When capturing this image, nothing was placed on the head side (first image A1 side), and the test piece was placed only on the stage side (second image A2 side). As can be seen from the image in FIG. 5B, there is a gradation in which the image gradually darkens from the second image A2 side to the first image A1 side. Furthermore, the second image A2 extends into the first image A1 area. Because diffusely reflected light is captured in the opposite field of view, the detection accuracy of the target may depend on the condition of the components in the opposite field of view.

[0115] On the other hand, an image acquired using the optical unit 1 and processing device 100 in this embodiment is shown in Fig. 6. When acquiring the image shown in Fig. 6, the first member P1 was not present on the head 4, and the second member P2, which had a specularly reflecting hollow circle mark, was placed on the stage 5 and imaged. As can be seen from Fig. 6, the third image A3 (matt portion) corresponding to the reflecting surface boundary 31d at the boundary between the two reflecting surfaces is clearly captured in the center of the composite image A, and the mark on the second image A2 side that exists near the boundary between the first image A1 and the second image A2 is also clearly captured.

[0116] In this way, with the optical unit 1 and processing device 100 in this embodiment, when capturing the first image A1 and the second image A2, a high-resolution composite image A can be obtained that is free of the loss and mixing of light caused by the two reflecting surfaces for the light from each of the first member P1 and the second member P2.

[0117] Furthermore, in this embodiment, the focal plane 21 of the camera lens 2 is aligned near the boundary between the two reflecting surfaces of the prism 31, so the boundary between the first image A1 and the second image A2 can be clearly detected. In particular, light from the upper and lower fields of view does not mix even near the boundary (field of view boundary) between the first image A1 corresponding to the upper field of view and the second image A2 corresponding to the lower field of view. Therefore, even when the first member P1 and the second member P2 are captured using diffuse reflected light, one of the first image A1 and the second image A2 does not extend into the other field of view (opposite field of view), resulting in a clear composite image A with relatively uniform brightness throughout the entire upper and lower fields of view. Moreover, because light from the upper and lower fields of view does not mix near the boundary between the first image A1 and the second image A2, there is no reduction in resolution near the boundary between the first image A1 and the second image A2, and no brightness gradation occurs in the composite image A due to light loss caused by the two reflecting surfaces.

[0118] Furthermore, in this embodiment, when capturing the first image A1 obtained from the first member P1 and the second image A2 obtained from the second member P2, an optical unit having a mirror for detecting intersection lines as in Patent Document 1 is not required, and no facility operation such as moving the optical unit 1 having the camera 11 to the location of this optical unit is required, and the first image A1 and the second image A2 can be captured on the spot. Therefore, errors due to facility operation do not occur, and productivity is improved.

[0119] Furthermore, in this embodiment, since the focal length of the camera lens 2 can be set to be short, a lens with a high NA can be selected as the camera lens 2. This allows the resolution of the composite image A to be further increased.

[0120] As described above, in this embodiment, not only can a high-resolution image of the boundary portion between the first image A1 and the second image A2 be obtained, but the entire composite image A including the first image A1 and the second image A2 can also be obtained at high resolution. This allows the correction amount D1 for the relative position between the first member P1 and the second member P2 to be calculated with high precision from the high-resolution composite image A. Therefore, the positioning of the first member P1 and the second member P2 can be performed with high precision. Furthermore, it is possible to minimize distortion associated with movement of units in the processing device 100 after correction, and to minimize the time from recognition correction to final positioning.

[0121] As described above, the optical unit 1 and processing device 100 in this embodiment include a light combining unit 3, a camera 11, and a camera lens 2. The light combining unit 3 has a prism 31 with at least two reflective surfaces, and a pair of work side lenses 32. The prism 31 is positioned so that the reflective surface intersection 31c, which is the intersection line of the two reflective surfaces, is located near the focal plane 21 of the camera lens 2. When imaging the first member P1 and the second member P2, one of the pair of work side lenses 32 is positioned between the prism 31 and the first member P1, and the other of the pair of work side lenses 32 is positioned between the prism 31 and the second member P2.

[0122] With this configuration, by capturing images of the first member P1 and the second member P2 with the camera 11 and acquiring a composite image A including a first image A1 of the first member P1 and a second image A2 of the second member P2, the image near the boundary (field of view boundary line) between the first image A1 corresponding to the first field of view and the second image A2 corresponding to the second field of view becomes high resolution, and therefore the correction amount D1 of the relative position between the first member P1 and the second member P2 can be calculated with high accuracy. This makes it possible to position the first member P1 and the second member P2 with high accuracy.

[0123] In addition, in the optical unit 1 and processing device 100 of this embodiment, the pair of work side lenses 32 are arranged so that the imaging surfaces of the first member P1 and the second member P2 are imaged on the focal plane 21 of the camera lens 2.

[0124] This configuration makes it possible to further increase the resolution of the image near the boundary between the first image A1 corresponding to the first field of view and the second image A2 corresponding to the second field of view, and also to increase the resolution of the entire composite image A. This makes it possible to calculate with higher accuracy the correction amount D1 for the relative position between the first member P1 and the second member P2, thereby enabling the positioning of the first member P1 and the second member P2 to be performed with even higher accuracy.

[0125] Second Embodiment Next, an optical unit 1A and a processing device 100A according to a second embodiment will be described with reference to Fig. 7 and Fig. 8. Fig. 7 is a diagram showing the configuration of the processing device 100A according to the second embodiment. Fig. 8 is an enlarged view of the boundary portion between the first reflecting surface 31a and the second reflecting surface 31b of the prism 31 used in the processing device 100A according to the second embodiment.

[0126] In the processing device 100A of this embodiment, of the light irradiated from the camera lens 2 side to the two reflecting surfaces (first reflecting surface 31a, second reflecting surface 31b) of the prism 31, some or all of the light near the reflecting surface intersection line 31c, which is the intersection line of the two reflecting surfaces, is reflected toward the camera lens 2 by a reflecting surface of the prism 31 other than the two reflecting surfaces.

[0127] Specifically, as shown in FIG. 7, in the processing device 100A of this embodiment, compared to the processing device 100 of the first embodiment shown in FIG. 1, the light combining section 3A of the optical unit 1A does not have a prism back illumination 33 but has a prism reflected illumination 35.

[0128] In this embodiment, the reflecting surface other than the two reflecting surfaces (first reflecting surface 31 a and second reflecting surface 31 b ) of prism 31 is a reflecting surface boundary 31 d of prism 31 .

[0129] 8, light 35a emitted from prism reflected illumination 35 is reflected by reflecting surface boundary 31d of prism 31 toward camera lens 2. Therefore, reflecting surface boundary 31d of prism 31 is capable of reflecting light 35a from prism reflected illumination 35 toward camera lens 2. Specifically, reflecting surface boundary 31d of prism 31 is processed at an angle that reflects prism reflected illumination 35 toward camera lens 2. This reflecting surface boundary 31d does not necessarily have to be a mirror surface, and may be any surface that reflects light to an extent that it can be captured by camera 11.

[0130] Furthermore, the processing method using the processing device 100A in this embodiment is basically the same as the processing method in the first embodiment, but in this embodiment, the light combining unit 3A of the optical unit 1A does not include the prism back illumination 33 but includes the prism reflection illumination 35. Therefore, when acquiring the composite image A in step S3, part or all of the light 35a irradiated from the prism reflection illumination 35 near the reflection surface intersection line 31c is directed toward the camera lens 2, and the light reflected at the reflection surface boundary 31d is captured by the camera 11 to acquire the composite image A. Then, as in step S4 in the first embodiment, the arithmetic device 6 calculates the boundary between the first image A1 and the second image A2 in the composite image A.

[0131] The processing device 100A of this embodiment, as in the first embodiment, uses the camera 11 to capture images of the first member P1 and the second member P2 to obtain a composite image A including a first image A1 of the first member P1 and a second image A2 of the second member P2. This results in a high resolution image near the boundary (field of view boundary line) between the first image A1 corresponding to the first field of view and the second image A2 corresponding to the second field of view, making it possible to calculate with high accuracy the correction amount D1 for the relative position between the first member P1 and the second member P2. This allows the first member P1 and the second member P2 to be positioned with high accuracy.

[0132] Furthermore, unlike the first embodiment, the processing device 100A in this embodiment can clearly detect the reflection surface boundary 31d by using the light 35a of the prism reflection illumination 35, and therefore can calculate the field of view boundary line A0 and the correction amount D1 from the detection result of the reflection surface boundary 31d, as in the first embodiment. In this case, there is no need to form the reflection surface boundary 31d as a light-transmitting surface between the first reflection surface 31a and the second reflection surface 31b, so the prism 31 can be manufactured more inexpensively than in the first embodiment. The structure of this embodiment is also effective in cases where it is desired to reduce the overall length of the optical unit 1A.

[0133] It is also possible to use the coaxial illumination 22 instead of the prism reflection illumination 35. In this case, if the detection contrast of the workpiece and the detection contrast of the reflective surface boundary 31d are within an appropriate range, the prism reflection illumination 35 does not need to be used.

[0134] Third Embodiment Next, an optical unit 1B and a processing device 100B according to a third embodiment will be described with reference to Fig. 9. Fig. 9 is a diagram showing the configuration of the processing device 100B according to the third embodiment.

[0135] 9, in a processing device 100B of this embodiment, compared to the processing device 100 of the first embodiment shown in FIG. 1, the light combining section 3B of the optical unit 1B does not include the back-of-prism illumination 33, but includes a plate 36 having a mark 36a. The plate 36 is a pre-prism mark plate located in front of the prism 31 (on the camera lens 2 side). Specifically, the plate 36 is located near the focal plane 21 of the camera lens 2.

[0136] The plate 36 is a substrate (for example, a transparent substrate such as glass) that transmits the wavelength band of light used in the camera 11, and has a non-transparent mark 36a attached thereto.

[0137] The marks 36a on the plate 36 can be clearly detected by imaging them reflected by the coaxial lighting 22, or by imaging the shadows that become opaque when the workpiece is imaged. However, the position of the plate 36 should be small, such as in the four corners of the field of view, and should be sized and positioned so as not to adversely affect workpiece detection. The position, shape, size, and number of the marks 36a are not particularly limited and can be designed in relation to the field of view in which the workpiece is imaged. For example, the marks 36a may be small marks near both ends of the reflective surface boundary 31d within the imaging field of view, or may be straight marks passing through the reflective surface intersection line 31c, which is the intersection line between the two reflective surfaces.

[0138] The processing device 100B of this embodiment, as in the first embodiment, uses the camera 11 to capture images of the first member P1 and the second member P2 to obtain a composite image A including a first image A1 of the first member P1 and a second image A2 of the second member P2. This results in a high resolution image near the boundary (field of view boundary line) between the first image A1 corresponding to the first field of view and the second image A2 corresponding to the second field of view, making it possible to calculate with high accuracy the correction amount D1 for the relative position between the first member P1 and the second member P2. This allows the first member P1 and the second member P2 to be positioned with high accuracy.

[0139] Moreover, unlike the first embodiment, the processing device 100B in this embodiment can calculate the field of view boundary line A0 based on the mark 36a in the obtained composite image A, and then calculate the correction amount D1. In this embodiment, the prism back illumination 33 is not required, so a compact optical unit 1B can be obtained. Furthermore, the process of forming a minute reflective surface boundary 31d at the boundary between the two reflective surfaces of the prism 31 to create a transmissive portion or a reflective portion is not required.

[0140] Fourth Embodiment Next, an optical unit 1C and a processing device 100C according to a fourth embodiment will be described with reference to Fig. 10. Fig. 10 is a diagram showing the configuration of the processing device 100C according to the fourth embodiment.

[0141] As shown in FIG. 10 , the processing apparatus 100C of this embodiment differs from the processing apparatus 100 of the first embodiment in the configuration of the light combining unit 3C of the optical unit 1C. Specifically, the light combining unit 3C of this embodiment includes a prism 37 having a first half mirror surface 37a and a second half mirror surface 37b, instead of the prism 31 having a first reflecting surface 31a and a second reflecting surface 31b in the first embodiment. The first half mirror surface 37a and the second half mirror surface 37b are the two reflecting surfaces of the prism 37, but they do not reflect all of the incident light but transmit a portion of the light. In other words, the first half mirror surface 37a and the second half mirror surface 37b transmit a portion of the incident light and reflect another portion of the incident light. The angle between the first half mirror surface 37a and the second half mirror surface 37b is approximately a right angle, specifically 90°. The back sides of the first half mirror surface 37a and the second half mirror surface 37b of the prism 37 are configured to transmit light.

[0142] Furthermore, the light combining section 3C of the optical unit 1C in this embodiment further includes a lens 38 and a plate 39 having a mark 39a on the side of the prism 37 opposite to the camera lens 2 side.

[0143] The plate 39 is a post-prism mark plate disposed behind the prism 37 (on the side opposite to the camera lens 2). The prism back illumination 33 is disposed behind the plate 39.

[0144] The marks 39a on the plate 39 are light-shielding films if the plate 39 is made of a light-transmitting material, and are light-transmitting holes if the plate 39 is made of a light-blocking material that does not transmit light. The marks 39a can be clearly imaged by using the prism backlight 33 behind the plate 39. If necessary, the marks 39a may be provided on both the front and back sides of the plate 39. Furthermore, the size, number, and arrangement of the marks 39a are not particularly limited as long as they can be used as a basis for calculating the field of view boundary line A0. Furthermore, the plate 39 may be divided into multiple parts if necessary.

[0145] The lens 38 and the prism 37 are arranged so that light from the mark 39a passes through the lens 38 and the prism 37 and is imaged on the focal plane 21 of the camera lens 2. The lens 38 may be a single lens, or may be a lens group made up of a plurality of lenses if necessary.

[0146] The processing device 100C of this embodiment, similar to the first embodiment, uses the camera 11 to capture images of the first member P1 and the second member P2 to obtain a composite image A including a first image A1 of the first member P1 and a second image A2 of the second member P2. This results in a high resolution image near the boundary (field of view boundary line) between the first image A1 corresponding to the first field of view and the second image A2 corresponding to the second field of view, making it possible to calculate with high accuracy the correction amount D1 for the relative position between the first member P1 and the second member P2. This allows the first member P1 and the second member P2 to be positioned with high accuracy.

[0147] Furthermore, in the processing device 100C of this embodiment, there is no need to use a prism 31 in which a reflective surface boundary 31d is provided between the first reflective surface 31a and the second reflective surface 31b, so imaging can be performed by making more effective use of the field of view.

[0148] It should be noted that, if the mark 39 a can be clearly imaged, the lens 38 need not be used. Furthermore, the light transmitting surface of the prism 37 on the side opposite to the camera 11 may be made curved, such that the light transmitting surface has a lens effect.

[0149] (Variations) The optical unit, processing device, processing method, etc. according to the present disclosure have been described above based on the first to fourth embodiments, but the present disclosure is not limited to the above first to fourth embodiments.

[0150] For example, the half mirror constituting the half mirror surface in the fourth embodiment can selectively transmit light depending on wavelength or polarization direction. In this case, if the light transmittance or reflectance is to be varied depending on wavelength, a dichroic mirror can be used as the half mirror. If the light transmission or reflection characteristics are to be varied depending on polarization direction, a polarizing beam splitter can be used as the half mirror. In this disclosure, the distinction between these two is not made and the term "half mirror" is used regardless of the means by which light is transmitted. The method is not important as long as the above-described effect is achieved by transmitting a portion of the light. For example, when using the characteristics of polarization, aligning the polarization directions of the two reflective surfaces of prism 37 and using camera 11 as a polarized camera allows separate and simultaneous capture of a workpiece image captured by reflection from prism 37 and a mark image captured by transmission through prism 37, thereby improving productivity.

[0151] In addition, the present disclosure also includes forms obtained by applying various modifications to the above-mentioned embodiments that would occur to a person skilled in the art, and forms realized by arbitrarily combining the components and functions of each embodiment within the scope of the present disclosure. Furthermore, the present disclosure also includes any combination of two or more claims from the multiple claims set forth in the claims at the time of filing, provided that there is no technical contradiction. For example, when a dependent claim set forth in the claims at the time of filing is made into a multiple claim or multiple multiple claims that cite all of the superordinate claims within the scope of the technical contradiction, the present disclosure also includes all combinations of claims included in that multiple claim or multiple multiple multiple claims.

[0152] The technology disclosed herein can be used as an optical unit used when positioning two components relative to each other or when positioning a component relative to a processing location, a processing device such as a positioning device that uses the optical unit, and a processing method such as a positioning method.

[0153] REFERENCE SIGNS LIST 1, 1A, 1B, 1C Optical unit 2 Camera lens 3, 3A, 3B, 3C Light combining section 4 Head 5 Stage 6 Calculation device 7 Display device 8 Calibration jig stage 10 Optical unit holding section 11 Camera 20 Optical axis 21 Focal plane 22 Coaxial lighting 31, 37 Prism 31a First reflecting surface 31b Second reflecting surface 31c Reflecting surface intersection line 31d Reflecting surface boundary 32 Workpiece side lens 32a First workpiece side lens 32b Second workpiece side lens 33 Prism back lighting 34 Oblique lighting 35 Prism reflected lighting 35a Light 36, 39 Plate 36a, 39a Mark 37a First half mirror surface 37b Second half mirror surface 38 Lens 81 Calibration jig 100, 100A, 100B, 100C Processing device P1 First member P2 Second member A Composite image A0 Field of view boundary line A1 First image A2 Second image A3 Third image M1, M2 Reference mark M3 Calibration jig mark N1, N2 Reference position N1' Projection reference position D1 Correction amount

Claims

1. An optical unit that images a first member held by a head and a second member held on a stage when calculating the relative position of the first member and the second member, the optical unit comprising: a light combining unit; a camera; and a camera lens, wherein the light combining unit has an optical element with at least two reflective surfaces and a pair of work-side lenses, each consisting of one or more lenses, and the optical element is positioned so that the intersection of the two reflective surfaces is located near the focal plane of the camera lens, and when imaging the first member and the second member, one of the pair of work-side lenses is positioned between the optical element and the first member, and the other of the pair of work-side lenses is positioned between the optical element and the second member.

2. The optical unit according to claim 1, wherein the pair of workpiece-side lenses are arranged so that the imaging surfaces of the first member and the second member are imaged on the focal plane.

3. The optical unit according to claim 1, further comprising an illumination device, the illumination device being positioned so as to be able to irradiate light from the side of the optical element opposite the camera lens side.

4. The optical unit according to claim 3, wherein part or all of the light irradiated from the side opposite the camera lens side of the optical element is transmitted to the camera lens side near the intersection line of the two reflecting surfaces.

5. An optical unit as described in claim 1, wherein part or all of the light irradiated from the camera lens side onto the two reflecting surfaces of the optical element in the vicinity of the intersection line of the two reflecting surfaces is reflected toward the camera lens by a reflecting surface of the optical element other than the two reflecting surfaces.

6. An optical unit according to claim 5, further comprising an illumination device, wherein light emitted from said illumination device is reflected towards said camera lens by a reflecting surface of said optical element other than said two reflecting surfaces.

7. The optical unit according to claim 1, further comprising an illumination device that emits light parallel to the optical axis of the camera.

8. The optical unit according to claim 1, further comprising an illumination device that irradiates light from an oblique direction relative to the optical axis of the camera.

9. The optical unit according to claim 1, wherein each of the pair of work-side lenses has a telecentric lens as the one or more lenses that is telecentric with respect to the first member and the second member side.

10. The optical unit according to claim 1, further comprising a plate having a mark near the focal plane of the camera lens.

11. The optical unit according to claim 1, wherein the two reflecting surfaces of the optical element are half-mirror surfaces that transmit a portion of light, and further comprising a member having a mark on the side of the optical element opposite to the camera lens side.

12. The optical unit according to claim 1, wherein the two reflecting surfaces of the optical element are concave surfaces of a concave mirror.

13. A processing device comprising an optical unit according to any one of claims 1 to 12 and a computing device, wherein the camera acquires images including the first member and the second member, and the computing device calculates a correction amount for the relative position between the first member and the second member based on the images, and positions the first member and the second member based on this correction amount.

14. The processing device according to claim 13, further comprising a calibration jig having a mark that can be imaged by the camera, wherein the arithmetic device calculates a correction amount for the relative position between the field of view position on the first member side and the field of view position on the second member side based on an image of the calibration jig imaged on the first member side and an image of the calibration jig imaged on the second member side.

15. The processing device according to claim 13, wherein the processing device is a component mounter.

16. A processing method for positioning the first member and the second member using the optical unit of claim 1, comprising the steps of: holding the first member with the head and holding the second member on the stage; disposing the optical unit between the head and the stage, and then focusing light from the first member that has passed through one of the pair of work-side lenses, after which it is reflected by one of the two reflecting surfaces of the optical element, thereby forming an image of the imaging surface of the first member on the focal plane of the camera lens; and focusing light from the second member that has passed through the other of the pair of work-side lenses, after which it is reflected by the other of the two reflecting surfaces of the optical element, thereby forming an image of the imaging surface of the second member on the focal plane of the camera lens, thereby obtaining a composite image including a first image of the first member and a second image of the second member; calculating, by a computing device, the boundary between the first image and the second image in the composite image, and calculating, from the boundary, a correction amount for the relative positions of the first member and the second member in the horizontal direction; and correcting the positions of the first member and the second member based on the correction amount.

17. The processing method described in claim 16, comprising the steps of: acquiring a third image by transmitting some or all of the light irradiated from the surface of the optical element opposite the camera lens side and capturing the light with the camera in the vicinity of the intersection line of the two reflecting surfaces of the optical element; and calculating the boundary between the first image and the second image in the third image by the arithmetic device.

18. The processing method described in claim 16, comprising the steps of: obtaining the composite image by directing part or all of the light irradiated from the camera lens side onto the two reflecting surfaces of the optical element in the vicinity of the intersection of the two reflecting surfaces toward the camera lens side, and capturing the light reflected by reflecting surfaces other than the two reflecting surfaces with the camera; and calculating the boundary between the first image and the second image in the composite image with the arithmetic device.

19. The processing method according to claim 16, comprising the steps of: positioning the optical unit above a calibration jig held on the stage or another stage, and capturing an image of the calibration jig from above to obtain a first calibration image; holding the calibration jig with the head, positioning the optical unit below the calibration jig, and capturing an image of the calibration jig from below to obtain a second calibration image; and calculating, by the arithmetic device, a correction amount for the relative position by adding a correction amount for the upper and lower field of view reference positions calculated based on the first calibration image and the second calibration image.

20. The processing method according to any one of claims 16 to 19, wherein the processing method is a method for manufacturing electronic or optical components, or a method for inspecting electronic or optical components.

21. The processing method according to any one of claims 16 to 19, wherein the processing method is a mounting method in which the first member is placed on the second member and joined.

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