JP2000263265A - Laser beam machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a precise position correction by picking up the picture of a work surface through the same optical path as that of a laser beam without causing a loss to a working laser beam. SOLUTION: In the position correction, a first movable reflection device 22 is arranged in the preceding stage of a working lens 24. In this device, a reflection mirror 86 is placed in the optical path of a laser beam to reflect the light of a ring light 32 reflected by the surface of a work object 30 to the input part 34a of a CCD camera 34 and the reflection mirror 86 is retreated to the outside of the optical path in outputting the laser beam from a laser oscillator. A personal computer as a controller calculates the coordinate of the work object 30 on the basis of picture data inputted from the CCD camera 34, compares the calculated value and the data in a memory means, outputs a deviation correction signal in the case deviation exists between both, and a position correction is done by moving a working table of a XY table on the basis of this correction signal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0101]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser processing apparatus, and more particularly to a laser processing apparatus having a laser irradiation position correcting mechanism using an image processing technique.

[0092]

2. Description of the Related Art In recent years, with the miniaturization of electronic devices, there has been a demand for miniaturization and high-density mounting of circuit elements used therein, and accordingly, wiring patterns for connecting each element have become thinner and thinner. Flexibility has been required.
FPC (Flexible Pri
(nt circuit) is formed by linearly etching a conductor such as copper adhered on a flexible film such as a polyimide, and an appropriate portion of each linear conductor is used for connection with an electronic element. Fine through holes are formed. Such F
In order to efficiently manufacture a PC, a large number of linear conductors are formed on the surface of a relatively large film sheet, and the formation of through holes in the lands (holes) of each conductor is completed. Therefore, it is suitable to cut the film sheet into required number of conductors. Then, in order to realize drilling of a large number of conductors formed on such a film sheet, use of a laser beam has been attempted.

Certainly, if a high-power laser beam such as a CO ₂ laser is pulse-oscillated and radiated onto the conductor land, the conductor and the polyimide can be removed instantaneously, and unnecessary dripping and distortion in the peripheral portion. Therefore, there is a possibility that the drilling of the FPC can be made more efficient. However, the film sheet that is the basis of the FPC is very thin and easily deformed such as elongation or distortion due to temperature change. Therefore, the accuracy of the position and pitch of each conductor formed on the surface is not necessarily high when viewed as a whole sheet. There is no feature. For this reason, even if the first conductor on each film sheet is accurately positioned, and the boring process is performed by automatic feeding according to the pitch between the conductors, the first conductor is caused by the deformation of the film sheet. There is a possibility that the aim gradually comes off due to the accumulation of the positional deviation of each conductor.

To solve this problem, it is effective to perform position correction using an image processing technique every time laser irradiation is performed a certain number of times. FIGS. 26 and 27 show such a conventional position correcting mechanism, in which a beam combiner 21 and a CCD camera 34 are arranged in front of a processing lens 24. FIG.
The beam combiner 21 is a mirror having a surface coated with a special coating so as to transmit the processing laser beam incident on the first surface 21a as it is and reflect visible light incident on the second surface. A laser beam emitted from a laser oscillator (not shown) passes through a light guide path including a predetermined optical system, and is directed to the first beam combiner of the beam combiner.
The light enters the surface 21a, passes through the surface 21a, and reaches the processing lens 24.
Then, the laser beam that has passed through the processing lens 24 is image-reversed and formed on the processing target object 30 to perform perforation processing (FIG. 26). An illumination means such as a ring light 32 is arranged near the processing lens 24. As shown in FIG. 27, visible light emitted from this illumination means is reflected on the surface of the processing object 30 and To the beam combiner 21 and pass through the beam combiner 21. Then, the visible light reflected on the second surface 21b of the beam combiner reaches the input unit 34a of the CCD camera 34. The visible light incident on the CCD camera 34 is converted into image data, subjected to various image processings, and transmitted to the control system of the system.

The image data captured by the CCD camera 34 is
This indicates the state of the surface of the object to be processed, and if the image data is different from the previously set image data, it can be determined that a positional shift has occurred. In addition, since the object 30 is placed on the XY table, the positional deviation can be eliminated by moving the object 30 in a predetermined direction by a predetermined amount. By executing the position correction using the image processing at appropriate intervals, it is possible to prevent the processing accuracy from being greatly reduced due to the accumulation of the positional deviation. In particular, as described above, the processing lens 24 and the CCD camera
By interposing the beam combiner 21 between the laser beam 34 and the optical path of the laser beam for processing and the optical path of visible light for observation on the same axis, extremely accurate position observation can be realized. The accuracy of the position correction can be maintained at a high level.

[0086]

However, in the conventional position correcting mechanism, since the beam combiner 21 is always present in the optical path of the laser beam, it can be said that the beam combiner 21 can transmit the laser beam. Also had certain losses and adverse effects. That is, the beam shape is deformed due to the attenuation or refraction of the laser beam, and this is an obstacle to further improving the processing accuracy. Further, since the beam combiner 21 is formed by applying a special coating process such as zinc selenide (ZnSe) to the surface of a glass material, there is also a problem that the beam combiner 21 is relatively expensive.

The present invention has been made to solve the above-mentioned conventional problems, and accurate position correction is possible by capturing an image of the surface of a processing object from the same optical path as a laser beam for processing. It is another object of the present invention to provide a laser processing apparatus provided with a position correction mechanism that can be realized at a relatively low cost without causing a loss to a processing laser beam.

[0098]

In order to achieve the above object, a laser processing apparatus according to the present invention forms an image of a laser oscillator and a laser beam output from the laser oscillator on a surface of an object to be processed. A processing lens, illumination means for illuminating the surface of the processing object, an image sensor such as a CCD camera for capturing an image of the surface of the processing object, storage means for storing data relating to the processing object, and the image sensor The position coordinates of the object to be processed are calculated based on the image data input from the CPU, and the calculation result is compared with the data of the object to be processed stored in the storage means. Control means for outputting a shift correction signal when it is determined that there is a workpiece, and a processing table on which the processing object is placed, and based on the shift correction signal output from the control means. Come, the laser machining apparatus equipped with an XY table for performing position correction by moving the required amount required direction the worktable, is characterized in that a movable reflecting means. The movable reflecting means interposes a reflecting member in the optical path of the laser beam when performing the position correction, and outputs the light of the illuminating means reflected on the surface of the processing object to the input section of the image sensor. And a mechanism for retracting the reflecting member out of the optical path when a laser beam is output from the laser oscillator. This movable reflecting means is provided at a stage before the processing lens,
That is, when the reflection member is disposed on the laser oscillator side, the reflection member can reflect the light of the illumination unit that has passed through the processing lens to the input unit of the image sensor.

In the above-mentioned laser processing apparatus, the reflection member is inserted in the optical path of the laser beam only when the position is corrected, and the image data of the surface of the object to be processed is input to the image sensor. Since a mechanism for retreating out of the optical path is provided, there is no loss or adverse effect due to the processing laser beam passing through the beam combiner as in the related art. In addition, during position correction, a reflecting member is interposed in the optical path of the laser beam, and image data of the surface of the workpiece is input to the image sensor through the same optical path as the laser beam. Can be realized. Furthermore, since the reflection member does not come into contact with the laser beam, a relatively inexpensive mirror can be used.

The movable reflecting means includes a driving source such as a rotary motor, a shaft driven by the driving source, a rotating body connected to the shaft, and a reflecting member provided on one surface of the rotating body. And those with As the above-mentioned rotating body, for example, a plate-shaped thing or a rod-shaped thing corresponds. In this case, when performing the position correction, the reflecting member moves in the optical path and reflects the light of the illuminating unit reflected on the surface of the processing target object to the input unit of the image sensor, and When the laser beam is output from the laser oscillator, the rotation direction and the rotation speed of the shaft are controlled so that the reflection member moves out of the optical path.

When the reflecting member is retracted out of the optical path, it is necessary to devise so that another portion of the rotating body does not intervene in the optical path to block the laser beam. For example, when the above-mentioned shaft is eccentrically connected to a position off the center of the rotating body, and the reflecting member moves in the opposite direction to the optical path, the other part of the rotating body is rotated so as not to reach the optical path. Adjusting the size and shape of the body. Or,
A through hole is formed in the rotating body, and when the reflecting member moves in a direction opposite to the optical path, the through hole is interposed in the optical path, and the laser beam passes through the through hole. You may.

Further, as the movable reflecting means, one having a driving source such as a linear motor and a reflecting member reciprocally driven by the driving source may be employed. In this case, when performing the position correction, the reflecting member moves in the optical path, and reflects the light of the illumination unit reflected on the surface of the processing target object to the input unit of the image sensor. When a laser beam is output from the laser oscillator, the moving direction and the moving speed of the reflecting member are controlled so that the reflecting member moves out of the optical path.

[0013]

FIG. 1 is a schematic explanatory view showing an overall image of a laser processing apparatus 10 according to the present invention. First, focusing on the laser optical system, the laser processing apparatus 10 includes a laser oscillator 12, a plurality of reflection mirrors 14a to 14h, a beam expander 16, a beam splitter 18, a pair of mask changers 20, 20, and , A pair of first movable reflectors 2
2, 22 and a pair of processed lenses 24, 24.

The laser oscillator 12 has a TEA (Transversely
Excited Atmospheric Geophysical) are formed of a CO ₂ laser oscillator. This TEACO ₂ laser oscillator is of a type in which a gas of about 1 atm (atmospheric pressure) or more is excited by discharge in a direction perpendicular to the axis of the laser tube, and can realize an extremely high pulse peak value with an extremely short pulse width. Has characteristics. Since the laser beam output from the TEACO ₂ laser oscillator 12 has a characteristic that the beam spread angle is relatively large, a long focal length lens 26 is interposed between the laser oscillator 12 and the first reflection mirror 14a. , Its spread is suppressed. Here, a laser oscillator having an output of 200 W and an emission wavelength of 9.3 μm is used as the laser oscillator 12.

The laser beam α output from the laser oscillator 12 and having passed through the long focal length lens 26 is reflected by the first reflecting mirror 14a, reaches the beam expander 16, and passes therethrough. The cross-sectional shape is shaped. That is, the cross section of the laser beam α emitted from the laser oscillator 12 is a square of 20 mm × 20 mm, but is shaped into a rectangle of 15 mm × 36 mm by passing through the beam expander 16.

The laser beam α emitted from the beam expander 16 is split into two directions by a beam splitter 18 provided in the optical path. The surface of the beam splitter 18 is provided with a special coating so that when a CO ₂ laser beam enters at an angle of 45 degrees, 50% of the CO ₂ laser beam is reflected and the remaining laser beam is transmitted. For example, a dielectric multilayer film using zinc selenide (ZnSe) or the like is applicable.

The first split laser beam β reflected by the beam splitter 18 is applied to a second reflecting mirror 14b.
Then, the light reaches the mask member 28 of the mask changer 20 via the third reflection mirror 14c. The mask member 28 is formed with a predetermined number of through holes of a predetermined shape in a predetermined number and pattern. The first branch is reduced to an arbitrary shape and number by passing through the through holes of the mask member 28. The laser beam β is reflected by the fourth reflecting mirror 14d and
To reach. The first light collected by this processing lens 24
Is inverted and image-formed on the surface of the processing object 30 to realize a drilling process.

The second branch laser beam γ transmitted through the beam splitter 18 also passes through the fifth reflecting mirror 14e, the sixth reflecting mirror 14f, and the seventh reflecting mirror 14g, and the mask member 28 of the mask changer 20 is also provided. To reach. And
The second branched laser beam γ narrowed by the mask member 28 into the same shape as described above is reflected by the eighth reflecting mirror 14h, reaches the processing lens 24, and is condensed and inverted on the surface of the processing object 30. An image is formed, and drilling is realized.

XY tables 36, 36 are arranged below the processing lenses 24, 24, respectively. Each of the XY tables 36 includes a processing table 38 on which the processing object 30 is set, a θ axis 40 for rotating the processing table 38 by a required amount to the left and right, and a processing table 38
And a Y-axis feed mechanism 44 for moving the worktable 38 and the X-axis feed mechanism 42 by the required amount in the Y-axis direction.

Stockers 46, 46 are arranged near the XY tables 36, 36, respectively, and a plurality of processing objects 30 are stored in each stocker 46 in a vertically stacked state. Each stocker 46 and the XY table 36
And loader / unloader mechanisms 48 and 48 composed of a belt conveyor, a pick-up arm, etc., are arranged, and the processing object 30 is sequentially taken out from a predetermined storage location in the stocker 46 to process the XY table. It functions to transport the work 30 to the table 38 (loader operation) and return the processed object 30 to the original storage location in the stocker 46 (unloader operation). Each of the processing objects 30 is arranged in a stackable manner in the stocker 46 so as to be able to move up and down, and when the processing of a certain processing object 30 is completed, 1
The loader operation of the next processing object 30 is performed by descending by the step.

In this laser processing apparatus 10, the laser beam α output from one laser oscillator 12 as described above is converted into a first split laser beam β and a second split laser beam γ by the beam splitter 18. The laser processing in the first processing stage 50 and the second processing stage 52 each including the mask changer 20, the first movable reflecting device 22, the processing lens 24, the XY table 36, etc., is performed simultaneously and in parallel. realizable.

As shown in FIGS. 2 and 3, the first movable reflection device 22 includes a pulse motor 83 which is arranged at a predetermined angle above (before) the processing lens 24, and a pulse motor 83 of the pulse motor 83. Rectangular rotating plate 8 fixedly connected to drive shaft 84
5 and have. A reflection mirror 86 is attached to the surface of the rotating plate 85. 4 and 5, the drive shaft 84 of the pulse motor 83 is eccentrically connected to a position off the center of the rotating plate 85. Therefore, by driving the pulse motor 83 to rotate the rotary plate 85, the reflection mirror 86 is disposed at a position where the optical path of the laser beam is blocked (FIG. 3) or retracted to a position deviated from the optical path (FIG. 2). It is possible to do.

Ring lights 32, 32 are arranged near the processing lenses 24, 24, and the surface of the processing object 30 is constantly illuminated by visible light emitted from the ring lights 32. Then, the illumination light (visible light) reflected on the surface of the processing target 30 passes through the processing lens 24 and is emitted upward. When the reflection mirror 86 of the first movable reflection device 22 is located in the optical path of the laser beam, this visible light is reflected by the reflection mirror 86 and enters the input section 34a of the CCD camera 34 (FIG. 3). That is, the CCD camera 34 can capture the visible light that has passed through the processing lens 24, and can use the same optical path as the laser beam for image data at the same location where the processing laser beam is irradiated. Means that it can be observed. In contrast,
When the reflection mirror 86 of the first movable reflection device 22 is located outside the laser beam path, the processing laser beam β (γ) directly enters the processing lens 24 (FIG. 2). The pulse motor 83 can freely adjust the rotation speed and the rotation direction according to an output signal from a control system described later.

FIG. 6 shows a specific example of the processing object 30. The processing object 30 includes a large number of linear conductors on the surface of a flexible film sheet 54 made of polyimide or the like. Those that formed 56 correspond. FIG. 7 is an enlarged view showing an example of the linear conductors 56.
One wiring pattern 58 is formed for each unit. Also,
At both ends of each linear conductor 56, rectangular lands 60, 60 indicating holes to be drilled are formed. A land pattern A is formed by the four lands 60 formed on the right end of each wiring pattern 58, and a land pattern B is formed by the four lands 60 formed on the left end. Each wiring pattern 58 is completed as an individual FPC 67 by cutting the film sheet 54 along a contour line 66 shown by a broken line after the completion of the perforation processing.

The wiring pattern 58 is formed on the film sheet 54.
Above, they are collectively arranged to form a plurality of blocks 68 (FIG. 6). FIG. 6 shows an example in which a total of 32 blocks of 8 × 4 are arranged at regular intervals. Also, as shown in FIG.
In the 68, 24 wiring patterns 58 are collected. Further, in the vicinity of each block 68, a dot-shaped correction mark 69 is arranged.

The film sheet 54 itself is very thin,
Since it is difficult to carry out automatic conveyance as it is, it is placed on the base plate 70 (FIG. 6). A pair of positioning pins 71 project diagonally from the surface of the base plate 70. By positioning the positioning pins 71 through the positioning holes 72 of the film sheet 54, the positioning between the base plate 70 and the film sheet 54 is performed. Is realized. If the base plate 70 is made of a material having a strong reflection characteristic, the laser light that has been perforated is reflected by the base plate 70 and may be incident on the object to be processed again to damage the same. It is desirable that the base plate 70 be made of a material having excellent laser light absorption characteristics such as graphite.

A steel holding plate 73 is overlaid on the surface of the film sheet 54 (FIG. 6). The holding plate 73 has a rectangular through window 74a corresponding to the land pattern A of the wiring pattern 58, a rectangular through window 74b corresponding to the land pattern B, and a correction mark 69.
Are formed for each block. As described above, by pressing the surface with the pressing plate 73, it is possible to effectively prevent the flexible film sheet 54 from being warped or wrinkled. A pair of positioning holes 75 are formed diagonally in the holding plate 73, and positioning with the base plate 70 is realized by inserting the positioning pins 71 of the base plate 70 into the positioning holes 75. The film sheet 54 is thus made up of the base plate 70 and the holding plate
It is stored in the stocker 46 while being sandwiched by 73, and transported onto the processing table 38 of the XY table.

As shown in FIG. 9, the mask member 28 is mounted on the mask changer 20 in a state of being fitted into the opening window of the mask holder 76. This mask holder 76 has 4
Windows 76a to 76d are formed.
Four mask members 28a to 28d are mounted so as to cover a to 76d. In the example of FIG. 9, intrinsic mask members 28a and 28b are attached to the two opening windows 76a and 76b. Among them, a mask pattern composed of four through holes 77 corresponding to the land pattern A of the wiring pattern 58 is formed on the first mask member 28a, and a land pattern B is formed on the second mask member 28b. A mask pattern including four corresponding through holes 77 is formed. Also the remaining opening windows
The third mask member 28c attached to 76c and 76d and the fourth mask member
The mask member 28d is a dummy mask member having no through holes formed therein.

The mask changer 20 is arranged so as to be able to reciprocate in the horizontal direction so as to block the optical path of the laser beam. This can be realized, for example, by slidably engaging the lower end portion 20a of the mask changer 20 with the linear guide 78 and moving the lower end portion 20a by a suitable driving means such as a pulse motor or an electromagnetic solenoid. By the reciprocating operation of the mask changer 20, the mask member 28 interposed in the optical path of the laser beam can be replaced (in FIG. 9, the second mask member 28b is connected to the optical path).
79 is shown interposed). By removing the retaining screws 80, 80 of the mask changer 20, the mask member 28 together with the mask holder 76 can be replaced. Therefore, when processing a wiring pattern in which three or more types of land patterns are included in one wiring pattern 58, the wiring pattern may be replaced with a mask holder having a mask member corresponding to each land pattern.

Next, a control system of the laser processing apparatus 10 will be described. As shown in FIG. 1, the laser processing apparatus 10 is basically driven and controlled by a single personal computer (hereinafter, referred to as a “PC 81”).
For example, data read by the CCD camera 34 and image-processed by the control board 82 is subjected to arithmetic processing by a central processing unit (CPU) of the personal computer 81 in accordance with a control program installed in an auxiliary storage device (HDD) of the personal computer. At the same time, a control signal based on the calculation result is output to the XY table 36, the laser oscillator 12, the loader / unloader mechanism 48, the stocker 46, and the like. The drive control of the pulse motor 83 of the movable reflection device 22 is also realized based on a control signal output from the personal computer 81.

That is, the two CCD cameras 34, 34 are connected to a personal computer 81 via a pair of control boards 82, 82, respectively. After the image processing, the image is taken into the personal computer 81. In addition, both XY tables 36, 36
Is connected to the personal computer 81 via the control boards 82 and 82, respectively.
The rotation of the θ-axis 40 and the movement in the XY directions are realized in accordance with the output signal from the personal computer 81. The laser oscillator 12 is also connected to the personal computer 81 via the control boards 82, 82, and on / off control of laser irradiation is realized based on an output signal from the personal computer 81. Although not shown, the pulse motors 83 of the first movable reflecting devices 22, 22 are also connected to the personal computer 81 via the control boards 82, 82, and respond to pulse signals output from the personal computer 81. Switching between the rotation and the stop and control of the rotation speed and the rotation direction are realized. A pair of monitors 83, 83 are connected to the personal computer 81 via control boards 82, 82, respectively.
Shows an enlarged image of the object 30 captured by the CCD camera 34.

In addition, loader / unloader mechanisms 48, 48,
The stockers 46, 46 and the mask changers 20, 20 are also connected to the personal computer 81 via the control boards 82, 82, respectively, and are driven and controlled in accordance with output signals from the personal computer 81. Also,
Although not shown, a motor-driven focus adjustment mechanism is built in the vicinity of each processing lens 24, 24, and this focus adjustment mechanism is also connected to the personal computer 81, and focuses on the basis of an output signal from the personal computer 81. Matching is performed. Note that the control boards 82, 82 are actually mounted in expansion slots of a personal computer.

Before executing the boring processing using the laser processing apparatus 10, it is necessary to set at least the following items. These settings are realized by inputting necessary values on a control program installed in the personal computer. (1) Selection of stage for performing laser processing Enter whether to perform processing in the first processing stage 50 and the second processing stage 52 at the same time or to perform processing in only one of the stages. (2) Setting of correction mark belonging to first block The distance to the correction mark 69 of the first block 68a is set with reference to one positioning pin 71 of the base plate 70 (0 coordinate) (FIG. 8). . More specifically, FIG.
As shown in FIG. 0, the distance GOffX in the X direction and the distance GOf in the Y direction
fY is input as “GOffX: 5500 μm, GOFFY: 20000 μm”. In addition, the size (diameter) of the correction mark 69 is input. As this size, for example, 420 μm
Is set. (3) Setting of Number of Blocks Arranged on Film Sheet The number of blocks 68 arranged on the film sheet 54 is set as, for example, “X direction: 8, Y direction: 4”. (4) Setting the distance between the blocks The distance between the blocks 68 is set to, for example, “X direction: 50,000 μm, Y direction: 60,000” based on the respective correction marks 69.
μm ”. (5) Input of the number of types of land patterns Taking the wiring pattern 58 shown in FIG. 7 as an example, two types of land patterns A and B are provided, and the number of land patterns is "2". When the wiring pattern 58 including more land patterns is processed, this value naturally increases accordingly. (6) Input of mask number corresponding to land pattern This is a setting for specifying the mask member corresponding to the land pattern.
Is selected, and the second mask member 28b is selected for the land pattern B. (7) Identification of the first processed part of each block As shown in FIG. 10, from the correction mark 69 of each block,
The distances OffX1 and OffY1 to the land pattern A of the first wiring pattern belonging to the block are, for example, “OffX1”.
1: 6850 μm, OffY1: 21650 μm ”. (8) Setting of Land Pattern A The number, shape, and size of the lands 60 constituting the land pattern A are set to, for example, “number of lands: 4, shape: square, size: length 30”.
0 μm, horizontal 300 μm ”. Land 6
The distances PitchX1 and PitchY1 between 0 and 60 are changed to “PitchX1: 1000
μm, PitchY1: 200 μm ”. (9) Specifying the start position of the land pattern next to each block As shown in FIG. 10, from the correction mark 69 of each block,
Distance OffX2 to the next one in the next land pattern (land pattern B) belonging to the block
And OffY2, for example, “OffX2: 41850 μm, OffY2: 2105
0 μm ”. (10) Setting of land pattern B The number, shape, and size of the lands 60 constituting the land pattern B are set to, for example, “number of lands: 4, shape: square, size: length 30”.
0 μm, horizontal 300 μm ”. Also, the distance PitchX2 between the lands is input as “PitchX2: 500 μm”. In the case of this land pattern B, Y
Since there is no deviation in the direction, there is no need to enter “PitchY2”. (11) Setting of Number of Processes per Land Pattern A numerical value corresponding to the number of wiring patterns 58 included in each block is input, for example, as “number of processes: 24”. (12) Pitch between land patterns The pitch between land patterns in one block is input. (13) Setting of laser conditions The frequency and the number of shots of the laser beam used for drilling are set to, for example, “frequency: 9.3 μm, number of shots:
1 ". Incidentally, in laser processing using a CO ₂ laser, an emission wavelength of 10.6 μm is generally selected. However, if a hole is formed in the FPC, flare is likely to occur and soldering will be difficult, so that the 9.3 μm
It is desirable to select a wavelength.

With the above settings, the type, position, shape, etc. of the land pattern to be punched by laser irradiation on the film sheet 54 are set in the control program. If these settings are made into a template for each type of the processing object and registered in the control program, it is possible to save the trouble of re-inputting the next time the same type of film sheet is processed. The above setting items are merely examples, and various other setting items can be prepared.

After the above setting is completed, the film sheet
The image of each correction mark 69 or land pattern placed on the 54 is captured by the CCD camera 34, and the difference between the coordinates where the correction mark or land pattern is actually located and the above set value is calculated. The XY table 36 may be moved to correct the error. For convenience of explanation, the operation will be described below mainly on one processing stage, but in practice, substantially the same process proceeds simultaneously in both processing stages.

First, a main switch (not shown) is turned on, and the laser oscillator 12, the CCD camera 34, and the XY table 36 are turned on.
And the like are set in a standby state, and execution of laser processing sequence control is commanded on the personal computer 81. When the above command is received, the XY table 36 moves around according to a preset program, and the CCD camera 34
The image below 24 is sent out. At this point, it goes without saying that the reflection mirror 86 of the first movable reflection device 22 is interposed in the optical path of the laser beam as shown in FIG. The image data input from the CCD camera 34 is input to the personal computer 81 after image processing on the control board 82. In the personal computer 81, matching is performed between the data on the preset correction mark 69 and the land pattern and the image data sent from the CCD camera 34, and the processing target is not placed on the XY table 36. Make sure that Next, the loader / unloader mechanism
A signal is output to 48 so that the first processing object 30 stored in the stocker 46 is transported, and the XY table 36 is moved to a position where the processing object 30 can be received.

As a result, when the processing object 30 is placed on the processing table 38 of the XY table 36, the CCD camera 34 moves the surface of the processing object 30 through the processing lens 24 by moving the XY table 36. Scanning is performed to detect whether or not the processing target 30 set on the processing table 38 has an inclination. The presence or absence of this inclination is detected, for example, as follows. First, the images of the correction marks 69 of each block 68 arranged in the X direction are captured by the CCD camera 34, and subjected to image processing to calculate the coordinates where the respective correction marks 69 are placed. An inclination is detected. Also, the inclination in the Y direction can be calculated by capturing the images of the correction marks 69 of each block 68 arranged in the Y direction with the CCD camera 34 and performing image processing on the images to calculate the coordinates where the respective correction marks 69 are placed. Is detected by As a result, when it is determined that the workpiece 30 has an inclination, the θ axis of the XY table is determined.
By rotating the 40 in the required direction by the required amount, the inclination is eliminated. The correction of the inclination of the processing target 30 is performed separately in the first processing stage 50 and the second processing stage 52.

Next, the CCD camera 34 captures an image of one positioning pin 71 as a reference within a predetermined range (FIG. 8), and detects the absolute coordinates of the positioning pin 71. Data relating to the shape, dimensions, position coordinates, and the like of the positioning pins 71 are registered in the control program in advance. Next, the coordinates at which the positioning pin 71 is located are set as a reference (zero coordinates), and the processing lens 24 is moved to the preset coordinates at which the correction mark 69 of the first block 68a is located.
Moves. Although the processing lens 24 is actually still, the relative position between the processing lens 24 and the processing object 30 is displaced by moving the XY table 36 side. The movement is described mainly with the lens 24. Also, during processing, as described above, the holding plate 73 is attached to the surface of the film sheet 54.
And only the correction marks 69 and land pattern portions are exposed through the penetrating window 74. Here, the description will be made with the holding plate 73 removed.

First block 68 by CCD camera 34
The image of the correction mark 69 of a is recognized, and the coordinates at which it is actually located are calculated. If there is a deviation between the preset position data and the actual coordinates, a deviation correction signal is output from the personal computer 81 to correct the deviation, and the XY table is output in accordance with the deviation correction signal.
36 moves the required amount in the required direction.

After completing the position correction on the correction mark 69, the processing lens 24 moves to the coordinates where the land pattern A belonging to the first block 68a is located, and the image around the land pattern A is moved within a preset range. take in. Then, the deviation between the actual position of the land pattern and the preset position is calculated by the same procedure as described above, and the XY table 36 is moved with an accuracy on the order of μm to correct the deviation. After the correction of the deviation is completed, the reflecting mirror 86 of the first movable reflecting device 22 is immediately retracted out of the optical path of the laser beam as shown in FIG. The drilling process is performed on the land pattern A. At this time, the first mask member 28a is interposed in the optical path of the laser beam. The laser beam emitted from the laser oscillator 12 is applied to the first mask member.
Since the light is split into four beams corresponding to the number of the lands 60 by passing through the 28a, it is possible to make a hole in the four lands 60 with one shot.

After the hole patterning process for the land pattern A positioned at the head is realized as described above, the XY table 36 is sequentially moved based on the preset pitch between the land patterns, and each time the laser beam is used. By all means
One drilling process is performed continuously. Then, in the thirteenth land pattern A of the first block 68a, after the reflection mirror 86 of the movable reflection device 22 is interposed again in the laser beam path and the position is corrected by the same image processing as described above,
The reflecting mirror 86 is retracted outside the laser beam path, and the drilling of the remaining land pattern A is continued. As described above, after the boring of the land pattern A belonging to the first block 68a is completed, the processing lens 24 moves to the top of the land pattern B of the first block 68a, where the same procedure as described above is performed. Performs position correction using image processing. Then, the second mask member 28b corresponding to the land pattern B is moved by the sliding operation of the mask changer 20.
Are arranged in the optical path 79 of the laser beam (FIG. 9), and the boring by the laser beam is continuously performed 12 times. Then, in the thirteenth land pattern B of the first block 68a, the position is corrected again by the same image processing as described above, and then the remaining land pattern B is punched.

As a result, at the time when the boring for all the land patterns belonging to the first block 68a is completed, the processing lens 24 moves to the correction mark 69 belonging to the second block 68b. After the position correction is performed, the boring of each land pattern belonging to the second block 68b is executed according to the same procedure as described above. Thereafter, according to the same procedure, the film sheet 54
Drilling is performed on each of the land patterns of the 32 blocks arranged above.

As described above, the first workpiece 30
Is completed, the object 30 on the XY table 36 is returned to the original position in the stocker 46 by the loader / unloader mechanism 48. And stocker
Each of the processing objects 30 stacked in 46 is lowered by one sheet, and the unprocessed processing object 30 is conveyed onto the XY table 36 by the loader / unloader mechanism 48, and the hole processing for the processing object 30 is performed. Be started.

The procedure of position correction by image processing used here is summarized below. First, based on the position data of the land pattern set in the control program in advance, after the processing lens 24 moves to the coordinates where the land pattern will exist, the CCD camera 34 moves the processing object 30 through the processing lens 24. The image of the surface is taken in a preset range. The captured image data is subjected to various types of image processing such as A / D conversion, binarization processing, filter processing, and edge enhancement processing by the control board 82, and then sent to the memory of the personal computer 81. The CPU of the personal computer 81 analyzes this image data according to a predetermined algorithm, and calculates the position coordinates where the land pattern is actually placed. Next,
The result of this calculation and the auxiliary storage device (HD
D) is compared with the position data of the land pattern set in D), and when it is determined that there is a deviation between the two, a deviation correction signal is generated, and this signal is transmitted to the control board 82 having the NC control function. Is output to the XY table 36. Then, by moving the processing table 38 in the required direction in the required direction in accordance with the displacement correction signal on the XY table 36, the displacement is eliminated. At this stage, the reflecting mirror 86 of the movable reflecting device 22 is retracted out of the laser optical path based on a command from the personal computer 81, and the laser oscillator
A laser beam is output from 12, and the laser beam that has passed through the processing lens 24 irradiates the land pattern without deviation.

In general, since the pitch between the land patterns belonging to one block 68 is relatively accurate, without correcting the position by image processing for each land pattern,
As described above, it is sufficient to perform the processing at regular intervals, but if higher processing accuracy is required, the frequency of position correction by image processing should be increased, or the position correction by image processing should be performed for each land pattern. May be implemented. Also, a correction mark 69 is set for each block 68, and once the position correction is performed on the correction mark 69 in units of the block, the process immediately proceeds to the position correction and the perforation processing of each land pattern. The processing lens 24 moves to the position where the first land pattern exists,
Therefore, it may be set to execute the position correction and the perforation processing by the image processing. Further, as described above, the stocker 46
A number of processing objects 30 are stored in the inside, and these are processed via a loader / unloader mechanism 48 into a processing table 38 of an XY table.
Is not an essential configuration for the present invention. For example, the workpiece 30 is manually moved to X
It may be configured to be set on the processing table 38 of the Y table, and to be replaced with an unprocessed processing object 30 when the boring of the processing object 30 is completed.

In this laser processing apparatus 10, the laser beam output from the laser oscillator 12 is branched into two by the operation of the beam splitter 18, and the drilling can be performed simultaneously on the two processing stages. Will be extremely high. Of course, even if two processing stages are operated at the same time, individual film sheets 54
Since the presence / absence and degree of positional deviation differ for each, the position correction itself using image processing is performed independently. Also,
When there is no need to perform simultaneous processing on two stages, by selecting a processing stage to be operated on the control program, processing on only one processing stage can be performed. More specifically, the XY table 36, the loader / unloader mechanism 48, etc. belonging to the processing stage that is not used are not operated, and the branch laser beam directed to the processing stage is blocked in the optical path by an appropriate shutter means. I do.

The rotating plate 85 of the first movable reflecting device 22 is
The laser beam may be driven so as to repeat the rotation / stop of 180 degrees every time the laser beam is irradiated / stopped, but it is also possible to rotate the laser beam at all times by synchronizing with the laser irradiation timing. That is, since the timing of laser irradiation and position correction is set in advance in the control program, by adjusting the rotation speed of the pulse motor 83 based on this, for example, when the position correction by image processing is completed, After the plate 85 rotates and retracts the reflection mirror 86 out of the optical path, the rotating plate 85 is rotated at a low speed so that the open state of the optical path is maintained until the laser irradiation of a preset number of times is completed. When performing position correction, the rotation speed of the pulse motor 83 may be variably controlled so that the reflection mirror 86 is surely returned to the optical path. In this way, by constantly rotating the rotary plate 85 without stopping, it is possible to prevent the vibration generated at the time of stop from adversely affecting the machining accuracy.

Instead of arranging the pulse motor 83 itself as described above, the pulse motor 83 is arranged so that the drive shaft 84 is vertical as shown in FIGS. Alternatively, an inclined member 87 may be provided, and a reflecting mirror 86 may be attached to the inclined surface 87a of the inclined member 87. Also in this case, the drive shaft 84 is eccentrically connected to a position off the center of the rotating plate 85, and the reflection mirror 86 is attached at a position protruding greatly from the main body of the pulse motor 83. Can be displaced between a position where the optical path of the laser beam is blocked (FIG. 11) and a position where the optical path is opened (FIG. 12).

Instead of mounting the rotary plate 85 eccentrically on the drive shaft 84 of the pulse motor 83 as described above, the drive shaft 84 is mounted at the center of the rotary plate 85 as shown in FIGS. It may be connected. In this case, an inclined member 87 is provided at one end protruding from the main body of the pulse motor 83, and a reflecting mirror 86 is attached to the inclined surface 87a, and at the other end protruding from the main body of the pulse motor 83. A through-hole portion 88 for passing a laser beam is formed. Then, the rotating plate is located at the position where the through hole 88 overlaps the optical path.
When 85 is rotated (FIG. 15), a laser beam passes through the through-hole portion 88, and laser processing is realized. When the rotating plate 85 is rotated to a position where the reflecting mirror 86 overlaps the optical path (FIG. 14), the light is reflected on the surface of the processing target 30 and the processing lens is processed.
It becomes possible to reflect the illumination light transmitted through 24 to the input section 34a side of the CCD camera.

Instead of mounting the rotary plate 85 directly on the drive shaft 84 of the pulse motor 83 as described above, the rotary plate 85 may be mounted on another shaft that is rotated via a suitable transmission member such as a gear or a belt. it can. Also, the reflecting mirror 86 is a rotating plate
Instead of being attached to 85, it may be configured to be attached to a rod-shaped rotating body.

FIGS. 16 to 19 show the second movable reflecting device 89.
And a housing 90 and guide grooves 91,
An inclined member 92 slidably engaged with 91 is provided, and a reflecting mirror 86 attached to an inclined surface 92a of the inclined member 92. A linear motor (not shown) is housed in the housing 92, and a drive shaft 93 protruding from the guide groove 91 and an inclined member 92 are connected. For this reason, the inclination member 92 is guided by the linear motion motor so that
It can be moved back and forth along 91.

The housing 90 is located above (before) the processing lens 24.
When the inclined member 92 moves to the left end, the optical path of the laser beam is blocked by the inclined member 92 and the reflection mirror 86 (FIG. 16), and when moved to the right end, the optical path is opened (FIG. 17). Positioned.

When performing position correction using image processing,
The inclined member 92 and the reflecting mirror 86 move to the left ends of the guide grooves 91 and 91 and are interposed in the optical path, and reflect the illumination light reflected from the surface of the processing object 30 toward the CCD camera 34 (FIG. 16). , FIG. 18). On the other hand, after the completion of the position correction, the inclined member 92 retreats to the right end of the guide grooves 91, 91 to open the optical path, thereby realizing the processing using the laser beam (FIGS. 17 and 19).

In the above, the holding of the holding plate 73 having the through-hole 74 on the surface of the film sheet 54 as the processing object 30 prevents the film sheet 54 from warping or wrinkling. Although the method has been described, this may be realized using another method. FIG. 20 to FIG. 22 show an example of the suction plate 102 in which a large number of fine intake ports 100 are formed in a matrix at a constant pitch.
Are fitted in the upper opening 38a of the box-shaped processing table 38. This adsorption plate 102 is formed of carbon graphite.

A cavity communicating with the intake port 100 is formed inside the processing table 38 (not shown). On one side surface of the processing table 38, five intake branch pipes 104 are airtightly connected. These intake branch pipes 104 are connected to and communicate with the cavity of the processing table 38. Further, each intake branch pipe 104 is connected to one intake pipe 106 in communication. This intake pipe 106
It is connected to a vacuum pump 112 through a fitting 108 and a flexible duct 110. Although not shown, the processing table 38 constitutes a part of the XY table 36 in the same manner as described above, the angle is variable by the rotation of the θ-axis, and the X-axis feed mechanism and the Y-axis feed A required amount can be moved in the XY directions by a mechanism.

When setting the film sheet 54 on the processing table 38, first, as shown in FIG. 21, positioning holes 72 formed at the four corners of the film sheet 54 are projected from the four corners of the surface of the suction plate 102. Positioning pin 114
And positioning between them is performed. Next, FIG.
As shown in FIG. 22, an iron frame member 116 is mounted on the surface of the film sheet 54. Positioning holes 118 are also formed at the four corners of the frame member 116, and by inserting these positioning holes 118 through the positioning pins 114,
Accurate positioning is achieved. In this state, when the suction operation by the vacuum pump 112 is started, the worktable 38
Negative pressure is generated inside, and the back of the film sheet 54
It will be absorbed by 100.

As described above, since the large number of air inlets 100 are evenly arranged on the surface of the suction plate 102, the film sheet 54 is stuck to the surface of the processing table 38 in a state of being completely stretched by the start of the suction operation. Attached, partial distortion and warpage are corrected. In this state, the laser oscillator 12 is operated, and the laser processing using the position correction by the image processing as described above is performed, so that accurate drilling is realized. Then, the suction operation is stopped at the time when the boring process for all the land patterns included in one film sheet 54 is completed, and the processed film sheet 54 is removed from the suction plate 102, and then the unprocessed film sheet 54 is unprocessed. The film sheet 54 is newly set.

Next, the illumination means of the laser processing apparatus 10 will be described. As the illuminating means, a ring light 32 composed of a normal halogen lamp or a fluorescent lamp can be used as described above.
A wavelength component that causes noise to the D camera 34 is also emitted at the same time, and image data captured by the CCD camera 34 may become unclear due to the influence of such a noise component. For this reason, it is desirable to remove the noise component as much as possible and use light having a wavelength suitable for the sensitivity region of the CCD camera 34 as illumination light.

FIG. 23 shows an example of this. The illuminating means 120 includes an emission section 122 arranged near the processing lens 24 and a light source unit 124. Inside this light source unit 124, a halogen lamp 126, a reflecting member 128,
A condenser lens 130, a cut filter 132, and an incident section 134 are arranged. A converging body 136 in which a number of optical fibers 135 are bundled is connected between the incident part 134 and the emitting part 122, and the converging body 136 is connected to the light source unit 124 and the emitting part.
It functions as a light guide between 122. The light generated by the lighting of the halogen lamp 126 is reflected by the reflecting member 128.
Reflected by the condenser lens 130,
After being narrowed down to a certain range of wavelengths by the light 32, the light reaches the incidence part 134, and is emitted from the emission part 122 to the outside via the converging body 136 of the optical fiber.

Inside the emission section 122, a tapered radiation surface 138 is formed so as to circularly surround the optical axis of the processing lens 24. As shown in FIG.
Are formed with a large number of fine radiation ports 140. In each emission port 140, an emission end 135a of the optical fiber 135 is provided.
Are arranged by a fixed number, and light from the light source unit 124 is emitted from each emission end 135a. As the cut filter 132, for example, a filter that transmits light having a wavelength of 600 nm to 700 nm included in the sensitivity region of the CCD camera 34 and removes other wavelength components is selected. For this reason,
The illumination light emitted from the emission end 135a is red light.

The film sheet 54 usually has a linear conductor
Bright surface with many 56 formed and almost linear conductor 56
Is not formed and there is a distinction from the dark back surface. Further, the base plate 70 and the adsorption plate 102 are made of black carbon graphite. Therefore, when the film sheet 54 is arranged on the black plate made of carbon graphite with the bright surface facing upward, the contrast between the two becomes clear, and sufficiently clear image data can be obtained even with ordinary illumination light. it can. On the other hand, when it is necessary to perform perforation processing from the back side of the film sheet 54, the contrast is reduced between the black plate and the dark back side, and sufficient image data cannot be obtained with ordinary illumination light. In contrast, as described above, a CCD camera
By cutting the wavelength component that hinders image input by 34, it is possible to clearly capture the outline on the film sheet 54 even when the subject side is relatively dark,
It is also possible to cope with a case where a hole needs to be punched from the back surface of the film sheet 54.

As described above, instead of extracting only a component of a specific wavelength from the light emitted from the halogen lamp 126 using the cut filter 132, the light within the sensitivity range of the CCD camera 34 is emitted from the beginning. The same effect can be obtained even if is used as lighting means. FIG. 25 shows an example of this, in which a plurality of mounting ports 142 are provided on the tapered radiation surface 138, and both terminals 148 of the red LED 146 are inserted into the fixing portions 144 arranged in the mounting ports 142, respectively. It becomes. The radiating surface 138 is formed so as to circularly surround the optical axis of the processing lens 24, as described above, and by turning on each LED 146, the CC
Red light having a wavelength of 660 nm, which belongs to the sensitivity region of the D camera 34, is applied to a processing location on the surface of the processing object, and the reflected light is reflected by the reflection mirror 86 and enters the CCD camera 34.

[0063]

In the laser processing apparatus according to the present invention, at the time of position correction, the reflecting member is interposed in the optical path of the laser beam, and the image data of the surface of the processing object passes through the same optical path as the laser beam for processing. Is input to the image sensor, so that highly accurate position correction can be realized. Moreover, the reflection member is interposed in the optical path of the laser beam only at the time of position correction. At the time of laser processing, the reflection member has a mechanism for retracting to the outside of the optical path to open the optical path. There is no loss or adverse effect on the processing laser beam. As described above, since the reflection member does not come into contact with the laser beam, there is an advantage that a relatively inexpensive mirror can be used as the reflection member.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing the entire structure of a laser processing apparatus according to the present invention.

FIG. 2 is a side view showing a first movable reflection device according to the present invention.

FIG. 3 is a side view showing a first movable reflection device according to the present invention.

FIG. 4 is a plan view showing a first movable reflection device according to the present invention.

FIG. 5 is a plan view showing a first movable reflection device according to the present invention.

FIG. 6 is a plan view showing a film sheet to be processed by the laser processing apparatus.

FIG. 7 is an enlarged view showing a wiring pattern and an FPC.

FIG. 8 is an enlarged plan view showing a part of the surface of the film sheet.

FIG. 9 is a front view showing a mask changer.

FIG. 10 is an explanatory diagram showing a method of setting a land pattern.

FIG. 11 is a side view showing a modification of the first movable reflection device.

FIG. 12 is a side view showing a modified example of the first movable reflection device.

FIG. 13 is a plan view showing another modification of the first movable reflection device.

FIG. 14 is a side view showing the modified example of the first movable reflection device.

FIG. 15 is a side view showing the modified example of the first movable reflection device.

FIG. 16 is a front view showing a second movable reflection device.

FIG. 17 is a front view showing a second movable reflection device.

FIG. 18 is a side view showing a second movable reflection device.

FIG. 19 is a side view showing a second movable reflection device.

FIG. 20 is a plan view showing an example in which a suction plate is mounted on a processing table.

FIG. 21 is a plan view showing a state in which a film sheet is set on a suction plate.

FIG. 22 is a plan view showing a state in which a film sheet is set on a suction plate.

FIG. 23 is an explanatory diagram illustrating an example of a lighting unit.

FIG. 24 is an enlarged sectional view showing the illumination means.

FIG. 25 is an enlarged sectional view showing another example of the illumination means.

FIG. 26 is a side view showing a conventional position correction mechanism.

FIG. 27 is a side view showing a conventional position correction mechanism.

[Explanation of symbols]

 10 Laser processing device 12 Laser oscillator 22 First movable reflector 24 Processing lens 30 Processing object 32 Ring light 34 CCD camera 34a CCD camera input unit 36 XY table 38 Processing table 83 Pulse motor 84 Drive shaft 85 Rotating plate 86 Reflecting mirror 88 Through hole 89 Second movable reflector

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2F065 AA03 BB27 CC01 CC02 EE05 FF04 GG02 GG17 JJ03 JJ26 LL03 LL09 LL12 LL26 LL30 LL46 MM03 QQ03 QQ04 QQ31 TT02 4E068 CA14 CB09 CC02 CD12 CE04 DA11

Claims (4)

[Claims] 1. A laser oscillator, a processing lens for forming an image of a laser beam output from the laser oscillator on a surface of a processing object, an illuminating means for illuminating the processing object surface, and an image of the processing object surface An image sensor that captures the data, storage means for storing data relating to the processing object, and calculating the position coordinates of the processing object based on the image data input from the image sensor; Control means for comparing the data of the object to be processed stored in the storage means and outputting a deviation correction signal when it is determined that there is a deviation between the two; and a processing table for mounting the object to be processed. An XY table for performing position correction by moving the processing table in a required direction by a required amount based on the deviation correction signal output from the control means. In the apparatus, when performing the position correction, a reflecting member is interposed in an optical path of the laser beam, and the light of the illumination unit reflected on the surface of the processing object is reflected to an input unit of the image sensor. And a movable reflecting means for retracting the reflecting member out of the optical path when a laser beam is output from the laser oscillator. 2. The movable reflecting means is disposed in front of the processing lens, and the reflecting member reflects light of the illumination means passing through the processing lens to an input portion of the image sensor. The laser processing apparatus according to claim 1, wherein: 3. The movable reflecting means includes a driving source, a shaft driven to rotate by the driving source, a rotating body connected to the shaft, and a reflecting member provided on one surface of the rotating body. When performing the position correction, the reflecting member moves in the optical path and reflects the light of the illumination unit reflected on the surface of the processing target object to the input unit of the image sensor, and the laser The shaft according to claim 1 or 2, wherein when the laser beam is output from the oscillator, the shaft is driven and controlled such that the reflection member moves out of the optical path to open the optical path. Laser processing equipment. 4. The movable reflecting means includes a driving source and a reflecting member reciprocally driven by the driving source. When performing the position correction, the reflecting member moves into the optical path and moves. While reflecting the light of the illumination means that has been reflected on the surface of the processing object to the input unit of the image sensor, when a laser beam is output from the laser oscillator,
The laser processing apparatus according to claim 1, wherein the reflection member is driven and controlled such that the reflection member moves out of the optical path to open the optical path.