JP5615660B2 - Machine tool with observation point focusing support function - Google Patents

Description

  The present invention relates to a machine tool (slicer, dicing machine, lathe, milling machine) having a function of observing an observation object (for example, a workpiece) using a microscope system.

  In Japanese Patent Application No. 2010-49407, the inventor is a grinding machine that grinds a workpiece by moving the rotating grinding wheel relative to the workpiece set on the chuck upper surface, and is movable in the vertical direction. Measuring a vertical distance between a reference plane of the microscope system and an observation object of the microscope system by processing a microscope system, a CCD camera that captures an image of the microscope system, and an image captured by the CCD camera The image processing device, the image processing device based on a sharpness that is a degree of whether or not the microscope system is in focus, the vertical direction of the reference plane of the microscope system and the observation object We have proposed a grinding machine with a distance measuring function, which is characterized by measuring the distance.

  According to such a grinding machine with a distance measuring function, the vertical distance between the reference surface of the microscope system and the observation object of the microscope system is measured based on the image of the microscope system. In measuring the vertical distance between the reference surface and the workpiece, the workpiece can be applied to a workpiece that is not damaged and has no electrical conductivity. The vertical distance between the grinding wheel and the workpiece can be obtained by utilizing the mutual positional relationship between the grinding wheel and the reference surface of the microscope system.

  Here, when a microscope system with an objective lens is used with respect to the microscope system, as shown in FIG. 6, so-called epi-illumination light is irradiated as spot-like light onto the observation object. Therefore, it can be determined relatively easily where the observation target is the observation point. However, when a microscope system with an objective lens is used, the so-called working distance (WD) is small (usually about 20 mm with a x20 objective lens), and it is necessary to bring the objective lens close to the observation object up to the distance. Therefore, there is a problem that coolant and mist adhere to the objective lens.

  On the other hand, when a telecentric optical microscope system having a lens principle as shown in FIG. 7 is used, the above problem does not occur because the working distance (WD) is large (usually about 50 to 150 mm). . However, when a telecentric optical microscope system is used, the so-called epi-illumination light becomes parallel light, so that there is a problem that it is difficult to easily focus on the observation object.

  The present invention has been made paying attention to the problem, and the object of the present invention is to provide an observation point specifying function that enables easy focusing on an observation object while using a telecentric optical microscope system. It is to provide a machine tool with.

The present invention includes a telecentric optical microscope system provided with a light source and an optical path for epi-illumination, a CCD camera for taking an image of the telecentric optical microscope system, and an oblique direction with respect to the optical path for epi-illumination. A first spot light source for projecting the first spot light; and a second spot light source for projecting the second spot light from an oblique direction with respect to the optical path for the incident illumination, wherein the first spot light is at least the At the focus level of the telecentric optical microscope system, the telecentric optical microscope system falls within the image of the telecentric optical microscope system, and the second spot light is also at least at the focus level of the telecentric optical microscope system. It will be within the image of the microscope system. The first is a spot light and the second spot light, in focus level of the telecentric optical microscope system has to be crossed with each other, and the first spot light source and the second spot light source, together A machine tool with an observation point specifying function characterized by projecting light of different spot diameters .

According to the present invention, since the telecentric optical microscope system is used and the working distance (WD) is large, the possibility that the coolant and mist adhere to the lens of the microscope system is small, while the first spot light and the first spot light Since the two-spot light intersects (overlaps) each other at the focal level of the telecentric optical microscope system, focusing on the observation object can be easily performed by identifying (determining) the intersection. Can do. In addition, it can be said that identification (discrimination) is easier in a situation where a small-diameter spot light is projected so as to overlap a large-diameter spot light.

Alternatively, the present invention provides a telecentric optical microscope system provided with a light source and an optical path for epi-illumination, a CCD camera that captures an image of the telecentric optical microscope system, and an oblique to the optical path for epi-illumination. A first spot light source for projecting a first spot light from a direction, and a second spot light source for projecting a second spot light from an oblique direction with respect to the optical path for the epi-illumination, wherein the first spot light is At least at the focus level of the telecentric optical microscope system, the telecentric optical microscope system is within an image of the telecentric optical microscope system, and the second spot light is also at least at the focus level of the telecentric optical microscope system. To be in the image of the optical microscope system It is, the first and the spot light and the second spot light at the focal position of the telecentric optical microscope system, adapted to most approach each other, the first spot light source and the second spot light source Is a machine tool with an observation point focusing support function characterized by projecting light beams having different spot diameters .

  According to the present invention, since the telecentric optical microscope system is used and the working distance (WD) is large, the possibility that the coolant and mist adhere to the lens of the microscope system is small, while the first spot light and the first spot light Since the two-spot lights are closest to each other at the focus level of the telecentric optical microscope system, it is possible to easily focus on the observation object by identifying (determining) the approach state. it can.

  Preferably, the telecentric optical microscope system, the first spot light source, and the second spot light source move up and down integrally with respect to the observation object. In this case, since the mutual positional relationship between these components is fixed, the occurrence of errors during focusing is effectively suppressed.

  Preferably, the first spot light source and the second spot light source are arranged symmetrically with respect to the optical path for epi-illumination. In this case, the overlapping or approach of the first spot light and the second spot light can be identified (discriminated) more clearly.

  Preferably, each of the first spot light source and the second spot light source has a light control means. In this case, the state of each spot light can be suitably adjusted according to the situation such as the brightness of the site.

  Preferably, the first spot light source and the second spot light source project spot lights having different colors (wavelengths). In this case, a combination of light colors can be preferably used. For example, when a red light (R) laser light source is used as the first spot light source and a green light (G) laser light source is used as the second spot light source, yellow (Y) is identified in the region where the two spot lights overlap. Therefore, the overlap or approach of the first spot light and the second spot light can be more clearly identified (discriminated).

  Preferably, the first spot light source and the second spot light source project light having different spot diameters. For example, it can be said that identification (discrimination) is easier in a situation where a small-diameter spot light is projected so as to overlap a large-diameter spot light. In this case, if the colors of the two spot lights are different, identification (discrimination) is further facilitated.

According to the present invention, since the telecentric optical microscope system is used and the working distance (WD) is large, the possibility that the coolant and mist adhere to the lens of the microscope system is small, while the first spot light and the first spot light Since the two-spot light intersects each other at the focal level of the telecentric optical microscope system, focusing on the observation object can be easily performed by identifying (determining) the intersection. In addition, it can be said that identification (discrimination) is easier in a situation where a small-diameter spot light is projected so as to overlap a large-diameter spot light.

  Alternatively, according to the present invention, since the telecentric optical microscope system is used and the working distance (WD) is large, the possibility that the coolant and mist adhere to the lens of the microscope system is small, while the first spot light And the second spot light are closest to each other at the focus level of the telecentric optical microscope system, and the focusing on the observation object is easily performed by identifying (determining) the approach state. be able to.

It is the schematic of the slicer (machine tool) with the observation point focusing assistance function in one embodiment of this invention. It is the schematic which shows the telecentric optical microscope system of FIG. 1, and its peripheral element. It is a figure explaining how the 1st spot light and the 2nd spot light look. It is a figure explaining how the 1st spot light and 2nd spot light of other embodiments look. It is a figure explaining how the 1st spot light and 2nd spot light of other embodiment look. It is the schematic for demonstrating the spot light which comes out of an objective lens. It is the schematic for demonstrating the principle of a telecentric lens.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a schematic diagram of a slicer (machine tool) with an observation point focusing support function according to an embodiment of the present invention. FIG. 2 is a schematic diagram showing the telecentric optical microscope system of FIG. 1 and its peripheral elements.

  As shown in FIGS. 1 and 2, the slicer 10 according to the present embodiment includes a chuck upper surface 11 on which a workpiece W is set. The chuck upper surface 11 can be translated in the X direction (left-right direction in FIG. 1) and the Y direction (direction perpendicular to the paper surface in FIG. 1). Further, the chuck upper surface 11 is rotatable around a rotation axis (not shown) in the XY plane (also having R degrees of freedom).

  The slicer 10 according to the present embodiment includes a rotating thin blade blade 12, and the workpiece W can be sliced by relatively moving the rotation axis of the rotating thin blade blade 12. .

  The slicer 10 according to the present embodiment includes a telecentric optical microscope system 21 that can move in the vertical direction. The telecentric optical microscope system 21 is connected to a CCD camera 22 that captures an image of the telecentric optical microscope system 21. The CCD camera 22 is connected to an image processing device 23 for observing an object to be observed, here, the upper surface of the work W by processing an image photographed by the CCD camera 22. Here, the image processing device 23 calculates the vertical distance between the reference surface 21s of the telecentric optical microscope system 21 and the observation object (the upper surface of the workpiece W) as a result of the observation of the observation object (the upper surface of the workpiece W). It can be measured. However, a simple monitor television may be connected instead of the image processing device 23.

  The telecentric optical microscope system 21 is characterized by a large inherent working distance (WD). The telecentric optical microscope system 21 has an autofocus function at a specific depth of field.

  As shown in FIG. 2, the telecentric optical microscope system 21 is provided with a light source 21a for epi-illumination, and an optical path from the light source 21a through the prism 21p to the observation object (the upper surface of the workpiece W). 21w is formed.

  Further, as shown in FIG. 2, the first spot light source 61 for projecting the first spot light from the oblique direction with respect to the incident light path 21w and the second spot from the oblique direction with respect to the incident light path 21w. And a second spot light source 62 for projecting light. The first spot light source 61 and the second spot light source 62 are supported and fixed integrally with the telecentric optical microscope system 21 by a support mechanism (not shown) so as to move up and down integrally with the telecentric optical microscope system 21. It has become. In the present embodiment, the first spot light source 61 and the second spot light source 62 are arranged symmetrically with respect to the optical path 21w for epi-illumination.

  The first spot light enters the image (in the imaging region) of the telecentric optical microscope system 21 at the focal level of the telecentric optical microscope system, and the second spot light also enters the telecentric optical microscope system. At the focal level, the telecentric optical microscope system 21 falls within the image. As shown in FIG. 3B, the first spot light and the second spot light cross each other at the focal level of the telecentric optical microscope system 21. As shown in FIGS. 3A and 3C, the first spot light and the second spot light are observed apart from each other above or below the focus level of the telecentric optical microscope system 21.

  Each spot light source 61, 62 is a laser light source of a laser beam having a small spot diameter in the present embodiment. The spot light is preferably visible colored light so that identification is easier. Further, the two spot lights are preferably spot lights having different colors (wavelengths). In this case, since the two spot lights appear to have different colors when the intersection state is established, it is easier to identify (determine) the intersection state. For example, the first spot light source 61 is preferably a red laser light source, and the second spot light source is preferably a green laser light source. In this case, when the two spot lights are in a crossing state, the light is yellow light, so that it is easier to identify (discriminate) the crossing state.

  In this embodiment, the image processing apparatus 23 includes a panel PC 23a and an image input board 23b. The video (image) from the CCD camera 22 is taken into the panel PC 23a via the image input board 23b, and various image diagnoses can be performed by the panel PC 23a. For example, various evaluations can be performed on the state of the workpiece after slicing.

  Furthermore, the panel PC 23a may be configured to evaluate the sharpness of each acquired image by an image processing program. Image sharpness is an index that indicates whether or not the subject is in focus, and it is possible to evaluate the absolute value of the image and the image that is slightly offset from the top, bottom, right, and left, and the correlation coefficient. Known to traders. In this case, the sharpness of the acquired image of the telecentric optical microscope system 21 is evaluated. Only when the sharpness of the acquired image of the telecentric optical microscope system 21 is the highest is the reference surface of the telecentric optical microscope system 21 and the observation object of the telecentric optical microscope system 21 (here, the upper surface of the work W). Corresponds to a state that corresponds to the working distance (WD) unique to the telecentric optical microscope system. That is, at the vertical position of the telecentric optical microscope system 21 when such a state is obtained, the panel PC 23a determines the vertical distance between the reference surface 21s of the telecentric optical microscope system 21 and the upper surface of the workpiece W by telecentricity. It can be measured (can be associated) as a working distance (WD) unique to the optical microscope system.

  Further, the image processing device 23 of the present embodiment can be connected to the NC device 31. For example, the image processing device 23 acquires coordinate values related to the reference plane of the telecentric optical microscope system 21 from the NC device 31. Then, the image processing device 23 determines the coordinate value related to the reference surface 21s of the telecentric optical microscope system 21 and the measured vertical distance (working distance (WD) unique to the telecentric optical microscope system). Based on this, the coordinate value of the upper surface of the workpiece W is determined. Then, the image processing device 23 sends the coordinate value of the upper surface of the workpiece W to the NC device 31.

  When a simple monitor television is connected instead of the image processing device 23, the operator can directly observe or evaluate the state of the workpiece visually.

  In addition, the telecentric optical microscope system 21 of the present embodiment is fixed (at least in the Z-axis direction) to a fixing member 13 that supports the rotation axis (main axis) of the thin blade 12 and is integrated with the fixing member 13. It is designed to move vertically. Thus, the vertical distance between the reference surface 21s of the telecentric optical microscope system 21 and the upper surface of the workpiece W is directly set to the vertical distance between the reference surface (for example, the lower limit) of the thin blade blade 12 and the upper surface of the workpiece W. It can be converted.

  The NC device 31 is connected to the fixed member 13 that supports the rotation axis (main axis) of the thin blade 12 and the drive control unit 41 that controls the vertical movement of the telecentric optical microscope system 21. The control unit 41 may be controlled.

  For example, the NC device 31 is configured to continuously scan the fixing member 13 and the telecentric optical microscope system 21 in the vertical direction via the drive control unit 41. Then, the image processing apparatus 23 continuously acquires images of the telecentric optical microscope system 21 during the scanning at predetermined time intervals, and also shows an image showing a peak of sharpness based on the sharpness of each acquired image. Thus, the vertical distance between the reference surface 21s of the telecentric optical microscope system 21 and the upper surface of the workpiece W is measured. Specifically, the vertical distance between the reference plane of the telecentric optical microscope system 21 and the upper surface of the workpiece W at the position of the telecentric optical microscope system 21 that brings about the sharpness peak during the scanning = the telecentric optical microscope system. A specific working distance (WD) is determined (measured).

  Next, the operation of the present embodiment as described above will be described.

  First, the fixing member 13 and the telecentric optical microscope system 21 that support the rotation axis (main axis) of the thin blade 12 are moved (scanned) in the vertical direction via the drive control unit 41 under the control of the NC device 31. . During the scanning, as shown in FIG. 3B, the telecentric optical microscope system 21 is extremely focused by identifying (determining) that the first spot light and the second spot light intersect each other. It can be done easily. When focusing is performed, the vertical distance between the reference surface of the telecentric optical microscope system 21 and the upper surface of the workpiece W = the working distance (WD) unique to the telecentric optical microscope system.

  Alternatively, at a predetermined time interval, images of the telecentric optical microscope system 21 are acquired by the image processing device 23 via the CCD camera 22, and the image processing device 23 processes each obtained image with a program called COGNEX. Thus, the sharpness that is the degree of whether or not the telecentric optical microscope system 21 is in focus may be grasped. Then, the vertical distance between the reference surface of the telecentric optical microscope system 21 and the upper surface of the workpiece W is measured by specifying an image showing a sharpness peak. Specifically, at the position of the telecentric optical microscope system 21 that brings about the sharpness peak during the scanning, the vertical distance between the reference surface 21s of the telecentric optical microscope system 21 and the upper surface of the workpiece W is expressed as the telecentric optical system. It may be determined (measured) as a working distance (WD) unique to the microscope system. In this case, the image processing apparatus 23 acquires the coordinate value regarding the reference plane 21s of the telecentric optical microscope system 21 from the NC apparatus 31 at the time of the measurement. Then, the coordinate value of the upper surface of the workpiece W is determined based on the coordinate value of the reference surface and the measured vertical distance (the working distance (WD) unique to the telecentric optical microscope system). Further, the image processing device 23 sends the determined coordinate value of the upper surface of the workpiece W to the NC device 31. Thereby, data (coordinate values) for NC machining control can be automatically created.

  Here, according to the present embodiment, by identifying the level (position) at which the spot light (for example, laser beams of different colors) from the spot light sources 61 and 62 intersects, the telecentric optical microscope system 21 The focus level can be easily identified, that is, the telecentric optical microscope system 21 can be focused very easily. Thereby, the observation point of the observation object can be easily specified (discriminated). That is, it is possible to easily identify which position of the workpiece W is being observed. Therefore, it is easy to translate the workpiece W in the XY plane according to the identification result.

  In addition, it is preferable that the spot light irradiation by the spot light sources 61 and 62 is performed only when necessary for work safety and energy saving. For example, it is preferable to provide an openable / closable shutter or other known dimming means for blocking or dimming the irradiation of the spot light from each spot light source 61, 62.

  According to the present embodiment as described above, since the telecentric optical microscope system 21 is used and the working distance (WD) is large, there is little possibility that coolant and mist adhere to the lens of the microscope system. Since the first spot light and the second spot light intersect (overlap) each other at the focus level of the telecentric optical microscope system, the focus on the observation object can be determined by identifying (determining) the intersection. Matching can be performed easily.

  In addition, even when the first spot light and the second spot light intersect each other at the focal level of the telecentric optical microscope system, the effects of the present invention can be expected even when they are closest to each other. FIG. 4 shows how the first spot light and the second spot light appear in such a case.

  In some cases, it is preferable that the first spot light source and the second spot light source project light having different spot diameters. FIG. 5 shows how the first spot light and the second spot light appear in such a case.

  In the above embodiment, if the vertical distance between the reference surface 21s of the telecentric optical microscope system 21 and the upper surface of the workpiece W is measured based on the image of the telecentric optical microscope system 21, the thin blade 12 And the reference plane 21s of the telecentric optical microscope system 21 can be used to obtain the vertical distance between the thin blade 12 and the workpiece W.

  In particular, if the telecentric optical microscope system 21 is moved (scanned) in the vertical direction via the drive control unit 41, the telecentric optical microscope system 21 at the position of the telecentric optical microscope system 21 that brings about the peak of sharpness. The vertical distance between the reference surface 21s and the upper surface of the workpiece W is measured, and the measurement can be performed semi-automatically.

  In order to obtain the coordinate value data more accurately, it is recommended that the telecentric optical microscope system 21 be moved a plurality of times in the vertical direction (scanning). However, rather than simply performing a plurality of scans, for example, the NC device 31 causes the telecentric optical microscope system 12 to scan roughly once in the vertical direction (fast) via the drive control unit 41, and the image processing device 23 , Continuously acquiring images of the telecentric optical microscope system 21 during the rough scanning at predetermined time intervals, specifying an image showing a peak of sharpness based on the sharpness of each acquired image, and The region including the vertical position corresponding to the image is extracted, and the NC apparatus 31 again re-squeezes the telecentric optical microscope system 21 in the vertical direction at least once in the vertical direction via the drive control unit 41 again. The image processing apparatus 23 scans the image of the telecentric optical microscope system 21 during the fine scanning for a predetermined time. The vertical distance between the reference surface 21s of the telecentric optical microscope system 21 and the observation object is specified by continuously acquiring images with sharpness of each acquired image and specifying an image showing a sharpness peak based on the acquired image sharpness. Is preferably measured. By such an aspect, the vertical distance between the reference surface of the telecentric optical microscope system 21 and the observation object can be measured semi-automatically and accurately and rapidly.

  In addition, it has been confirmed by actual experiments by the present inventors that the depth of field of the telecentric optical microscope system 21 used in the above-described embodiment is preferably a shallow (small) value. Specifically, the distance measurement error when using a telecentric optical microscope system having a depth of field of 70 μm is 20 μm to 30 μm, whereas the telecentric optical system having a depth of field of 17 μm. The distance measurement error when using the microscope system was about 5 μm. Therefore, it is recommended to use a telecentric optical microscope system with a shallow depth of field for slicers that require higher precision machining. Specifically, a depth of field of about 5 μm to 20 μm is preferable.

DESCRIPTION OF SYMBOLS 10 Slicer with observation point focusing support function Chuck upper surface 12 Thin blade blade 13 Fixed member 21 Telecentric optical microscope system 21s Reference surface 21a Epi-illumination light source 21p Prism 21w Epi-illumination optical path 22 CCD camera 23 Image processing device 23a Panel PC
23b Image input board 31 NC unit 41 Drive control unit 61, 62 Spot light source (laser light source)

Claims (7)

A telecentric optical microscope system provided with a light source and an optical path for epi-illumination,
A CCD camera for taking an image of the telecentric optical microscope system;
A first spot light source that projects the first spot light from an oblique direction with respect to the incident light path;
A second spot light source that projects the second spot light from an oblique direction with respect to the incident light path;
With
The first spot light is within an image of the telecentric optical microscope system at least at a focus level of the telecentric optical microscope system;
The second spot light also enters an image of the telecentric optical microscope system at least at the focal level of the telecentric optical microscope system,
The first spot light and the second spot light intersect each other at the focus level of the telecentric optical microscope system ,
The machine tool with an observation point focusing support function, wherein the first spot light source and the second spot light source project light having different spot diameters . A telecentric optical microscope system provided with a light source and an optical path for epi-illumination,
A CCD camera for taking an image of the telecentric optical microscope system;
A first spot light source that projects the first spot light from an oblique direction with respect to the incident light path;
A second spot light source that projects the second spot light from an oblique direction with respect to the incident light path;
With
The first spot light is within an image of the telecentric optical microscope system at least at a focus level of the telecentric optical microscope system;
The second spot light also enters an image of the telecentric optical microscope system at least at the focal level of the telecentric optical microscope system,
The first spot light and the second spot light are closest to each other at a focal position of the telecentric optical microscope system ,
The machine tool with an observation point focusing support function, wherein the first spot light source and the second spot light source project light having different spot diameters . 2. The telecentric optical microscope system, the first spot light source, and the second spot light source are configured to move up and down integrally with respect to the observation object. 2. A machine tool with an observation point focusing support function described in 2. The observation point focus according to any one of claims 1 to 3, wherein the first spot light source and the second spot light source are arranged symmetrically with respect to the optical path for epi-illumination. Machine tool with alignment support function.   The machine tool with an observation point focusing support function according to any one of claims 1 to 4, wherein each of the first spot light source and the second spot light source has a light control means. . 6. The observation point focusing support function according to claim 1, wherein the first spot light source and the second spot light source project spot lights of different colors from each other. Machine tool with. The first spot light source is a red laser light source,
The machine tool with an observation point focusing support function according to claim 6, wherein the second spot light source is a green laser light source.

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