JPH09141471A - Laser beam processing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to execute high-accuracy fine laser beam processing in the case work pieces vary slightly in their shapes with each work piece or the case the work pieces are subjected to high-accuracy fine processing. SOLUTION: This laser beam processing machine has an X-Y table 3 on which the work piece 2 is placed and which is slidable arbitrarily in X-Y directions by a driving mechanism 4, laser beam irradiation sections 5, 6 which irradiate the work piece 2 with the laser beam from a laser oscillator 5 through an optical system 6 to process the work piece and mark detecting sections 7 to 9 which detect the positions of the >=2 alignment marks formed on the work piece 2. These mark detecting sections 7 to 9 successively detect the >=2 alignment marks to make rough adjustment, then successively detect these marks to make fine adjustment. The X-Y table 3 is slid by the driving mechanism 4 in accordance with the results of the detection made by the mark detecting sections 7 to 9 to adjust the alignment until the placing position of the work piece 2 is aligned to the prescribed processing position.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser processing apparatus, and more particularly, it detects at least two alignment marks provided on a work (work) and places the work on an XY table according to the detection result. The present invention relates to an alignment mechanism in a laser processing apparatus having an alignment mechanism that matches a placement position with a predetermined processing position.

[0002]

2. Description of the Related Art Generally, when a laser beam is used to machine an object to be machined, the position of the object to be machined and the laser beam machine to be machined before the laser machining of the object to be machined. The workpiece is placed and moved to an optimum position for laser processing, that is, alignment adjustment of the workpiece is performed so that the irradiation position of the laser light emitted from the laser light irradiation unit coincides.

By the way, alignment adjustment of a work piece in a known laser processing apparatus is performed from an alignment bar or the like on a work piece mounting table or a work piece mounting plate used for laser processing the work piece. When the workpiece is placed on a mounting table or a mounting plate, the workpiece position regulating member is formed so that the optimum placement position is determined by the workpiece position regulating member including an alignment bar. An example of such alignment adjustment is disclosed in US Pat. No. 4,118,730.

The above-mentioned US Pat. No. 4,118,73
In the one disclosed in the specification No. 0, the alignment adjustment of the workpiece is performed by the workpiece position restricting member such as an alignment bar, the workpiece is scanned and photographed by using a video camera, and an image pickup signal thereof is obtained. The shape of the work piece is grasped by.

[0005]

By the way, alignment adjustment of a workpiece in a known laser processing apparatus is
Since the position of the work piece is controlled by the work piece position restricting member such as an alignment bar, when the shape of the work piece is slightly different for each work piece, the liquid crystal display When it is necessary to perform high-precision micromachining on a workpiece, such as when manufacturing a color filter or the like used for the parts, it is not possible to accurately perform alignment adjustment of the workpiece, By the way,
There is a problem that high-precision fine processing cannot be performed at the time of laser processing of the work piece.

The present invention solves the above problems,
The purpose is an alignment mechanism in a laser processing apparatus capable of performing high-precision fine laser processing when the shape of each work is slightly different or when performing high-precision fine processing of the work. To provide.

[0007]

In order to achieve the above-mentioned object, the present invention is designed so that a work piece is placed and X is driven by a drive mechanism.
XY that can slide freely in the (horizontal axis) direction and the Y (vertical axis) direction
A table and a laser light irradiating unit for irradiating the workpiece with a laser beam derived from a laser oscillator through an optical system to perform laser processing on the workpiece, and at least 2 provided on the workpiece. A mark detection unit that sequentially performs fine adjustment detection after sequentially performing coarse adjustment detection of the positions of the two alignment marks, and the drive mechanism performs the XY adjustment based on the detection result of the mark detection unit.
It is provided with an alignment mechanism that slides the table to match the mounting position of the workpiece with a predetermined processing position.

In the above mechanism, the workpiece is provided with at least two alignment marks, and the mark detection unit performs coarse adjustment detection of the positions of these alignment marks and subsequent fine adjustment detection. Since the alignment is adjusted so that the placement position of the work piece matches the predetermined processing position based on, even when the shape of the work piece is slightly different for each work piece, Alternatively, at least two alignment marks provided on the workpiece are detected even when performing high-precision fine laser processing of the workpiece as in the case of manufacturing a color filter used in a liquid crystal display unit. If possible, it becomes possible to perform alignment adjustment so that the placement position of the workpiece on the XY table matches the predetermined laser processing position.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a block diagram showing a laser processing apparatus provided with an alignment mechanism of the present invention.
Is a side view, and FIG. 1B is a top view.

As shown in FIGS. 1 (a) and 1 (b), the laser processing apparatus 1 mainly includes a workpiece 2 to be processed.
An XY table 3 on which the workpiece 2 is placed and slidable in the vertical and horizontal directions, a drive mechanism 4 including a linear motor for sliding the XY table 3, a laser oscillator 5 for generating a laser beam, and 2 The two condensing lenses 6 (1) and 6 (2), an optical shutter (not shown), a reflecting mirror (not shown), etc. are built in, and the laser beam generated by the laser oscillator 5 is intermittently applied to the workpiece 2. An optical system 6, a coarse adjustment CCD camera 7, a fine adjustment CCD camera 8, a lens barrel 9 containing a reflecting mirror (not shown) and the like, and a surface plate 10 with an anti-vibration foot 10 (1). It consists of

In this case, the laser oscillator 5 and the optical system 6
Is a laser light irradiation unit, and a CCD camera 7 for coarse adjustment
The fine adjustment CCD camera 8 and the lens barrel 9 constitute a mark detection unit. The workpiece 2 is, for example, a color filter used in a liquid crystal display unit, and one alignment mark 11 (only one is shown) is provided at each end of the color filter. The drive mechanism 4 is a horizontal (X) axis direction linear motor yoke 4X.
(1) and a pair of lateral (X) axial rails 4X (2) and 2
Two vertical (Y) axis direction linear motor yokes 4Y (1) and 2
It is provided with a pair of vertical (Y) axial direction rails 4Y (2).

Then, the XY table 3 is appropriately moved in the horizontal (X) axis direction and the vertical (Y) axis direction by the drive of the drive mechanism 4, and the workpiece 2 placed on the XY table 3 is also XY. As the table 3 moves, the table 3 moves in the horizontal (X) axis direction and the vertical (Y) axis direction. The laser light irradiation unit irradiates the workpiece 2 with the laser light generated by the laser oscillator 5 through the optical system 6, and laser-processes the workpiece 2. In this case, the laser beam applied to the workpiece 2 is the optical system 6
Is interrupted by an optical shutter (not shown) built into the
The workpiece 2 is intermittently irradiated with laser light. The mark detection unit determines the position of the alignment mark 11 provided on the workpiece 2, for example, the color filter, from the lens barrel 1
0 through coarse adjustment CCD camera 7 and fine adjustment CCD
The image is picked up by the camera 8 and a detection output indicating the position coordinates is generated. In this case, each alignment mark 11
On the other hand, first, position detection is performed by the coarse adjustment CCD camera 7, and then position detection is performed by the fine adjustment CCD camera 8.

Next, FIG. 2 is a constitutional view showing an alignment mark detecting portion in the laser processing apparatus shown in FIG. 1, FIG. 2 (a) is a perspective view thereof, and FIG. 2 (b) is a sectional view thereof. The same components as those shown in FIGS. 1A and 1B are designated by the same reference numerals.

As shown in FIGS. 2 (a) and 2 (b), the lens barrel 9 has two reflecting mirrors 9 (1), 9 (2) arranged in tandem therein, and these reflecting mirrors 9 (1). , 9 (2), a coarse adjustment CCD camera 7 and a fine adjustment CCD camera 8 are arranged respectively. The position adjusting plate 1 is provided at the tip of the lens barrel 9.
2 is arranged, the objective lens 13 is attached to the position adjusting plate 12, and the height (Z) direction position adjusting motor 14 is connected. An optical fiber 9 (3) for supplying illumination light is connected to the base of the lens barrel 9, and a height direction position adjusting motor 14 is attached to the side surface of the lens barrel 9.

Then, by driving the driving mechanism 4, the XY table 3 is appropriately moved so that the object lens 13 faces the workpiece 2, for example, the alignment mark 11 provided on the color filter used in the liquid crystal display section. At the same time, after adjusting the height direction position adjusting motor 14 to adjust the height of the objective lens 13 with respect to the alignment mark 11, the illumination light supplied from the optical fiber 9 (3) is changed to
The light is projected onto the alignment mark 11 through the two reflecting mirrors 9 (1) and 9 (2) in the lens barrel 9 and the objective lens 13 attached to the position adjusting plate 12. At this time, the image of the alignment mark 11 illuminated by the illumination light is passed through the objective lens 13 and the two reflecting mirrors 9 (1) and 9 (2) to the coarse adjustment CCD camera 7, and the objective lens 13 and the reflecting mirror 9 ( 2) is transmitted to the CCD camera 8 for fine adjustment through the CCD camera 7 for coarse adjustment and the CCD for fine adjustment.
The image is projected by the camera 8, and the alignment mark 11 is roughly and finely adjusted. In this case, the alignment mark 11
The coarse adjustment and the fine adjustment are performed by measuring the barycentric position of the alignment mark 11 in the images projected by the coarse adjustment CCD camera 7 and the fine adjustment CCD camera 8.

Next, FIG. 3 is a flow chart showing an operation process when carrying out alignment adjustment and subsequent laser processing in the laser processing apparatus having the alignment mechanism of the present invention.

Each operation of alignment adjustment and subsequent laser processing performed by the laser processing apparatus of the present invention will be described with reference to the flowchart shown in FIG.

First, in step S1, each part of the laser processing apparatus 1 is initialized.

Next, in step S2, the origin position coordinates are measured by image processing to find the correlation between the physical origin position coordinates in the XY table 3 and the origin position coordinates in the alignment adjustment optical system.

Then, in step S3, it is set whether the laser processing apparatus 1 is automatically operated or not. When the automatic operation is set (Y), the process proceeds to the next step S4, and when the automatic operation is not set (N), the series of flowcharts is ended.

Next, in step S4, the drive mechanism 4 composed of a linear motor is driven to move the XY table 3 to a position (workload position) where the workpiece 2 can be placed.

Subsequently, in step S5, the workpiece 2 is placed (workload) on the XY table 3.

Next, in step S6, the drive mechanism 4
Is driven so that the one (first) alignment mark 11 provided on the workpiece 2 substantially coincides with the position of the objective lens 13 below the lens barrel 9 constituting the mark detection unit. The XY table 3 is transferred.

After that, in step S7, the first alignment mark 11 is projected by the coarse adjustment CCD camera 7 in a state where the first alignment mark 11 is illuminated by the illumination light from the optical fiber 9 (3). Rough adjustment using the first alignment mark 11 is performed by measuring the position of the center of gravity of the image.

Next, in step S8, the drive mechanism 4 is driven again, and the other one (second) alignment mark 11 provided on the workpiece 2 is also located below the lens barrel 9. X so that it almost coincides with the position of the lens 13.
Y table 3 is transferred.

Then, in step S9, the second alignment mark 11 is illuminated again by the illumination light from the optical fiber 9 (3), and the second alignment mark 11 is again imaged by the coarse adjustment CCD camera 7 and then imaged. By measuring the position of the center of gravity of the image, rough adjustment using the second alignment mark 11 is performed.

Here, in step S10, the image processing conditions of the laser processing apparatus 1 are changed to conditions different from the above-mentioned conditions. The new image processing condition is that the intensity of the illumination light from the optical fiber 9 (3) is increased, the height direction position adjusting motor 14 is driven, and the distance from the surface of the workpiece 2 to the objective lens 13 is predetermined. Adjust to the value of
It is changed so as to execute precision image processing using the fine adjustment CCD camera 8.

Next, in step S11, the drive mechanism 4 is driven, and the second alignment mark 11 provided on the workpiece 2 is located below the lens barrel 9 of the objective lens 13.
The XY table 3 is slightly moved so as to match the position of.

After that, in step S12, the second alignment mark 11 is projected by the fine adjustment CCD camera 8 while being illuminated by the illumination light from the optical fiber 9 (3). By measuring the position of the center of gravity of the image, fine adjustment using the second alignment mark 11 is performed.

Subsequently, in step S13, the drive mechanism 4 is driven again, and the first alignment mark 11 provided on the workpiece 2 coincides with the position of the objective lens 13 below the lens barrel 9. Thus, the XY table 3 is moved.

Next, in step S14, the first alignment mark 11 is projected by the coarse adjustment CCD camera 7 while being illuminated by the illumination light from the optical fiber 9 (3). By measuring the barycentric position of the image, fine adjustment using the first alignment mark 11 is performed.

After these adjustments have been made, step S1
5, based on the coordinate position obtained by the fine adjustment using the first alignment mark 11 and the coordinate position obtained by the fine adjustment using the second alignment mark 11, the orthogonal coordinate ( XY system) and XY
The angle deviation θ and the positional deviations Δx and Δy from the physical rectangular coordinate (XY coordinate) system in the table 3 are calculated.

Thereafter, in step S16, the drive mechanism 4 and the angle adjusting mechanism (not shown) are driven,
The XY table 3 is slightly rotated and slightly moved so as to eliminate the above-mentioned angular deviation θ and positional deviations Δx and Δy.

Next, in step S17, the laser processing apparatus 1 corrects the angular deviation θ due to the rotation of the XY table 3 performed in step S16 and corrects the XY table 3.
It is determined whether or not the angular deviation θ and the positional deviations Δx and Δy have been corrected by correcting the positional deviations Δx and Δy due to the movement of. Then, the angular deviation θ and the positional deviation Δ
When it is determined that x and Δy have been corrected (Y), the process proceeds to the next step S18, while when it is determined that these angular deviation θ and positional deviations Δx and Δy have not been completely corrected (N), The process returns to step S11 described above, and the processes after step S11 are repeatedly executed.

In step S18, the control system of the laser processing apparatus 1 shifts to the laser processing orthogonal coordinate system.

After that, in step S19, the laser light projected from the condenser lenses 6 (1) and 6 (2) in the laser light irradiation portion to the processing point of the workpiece 2 is automatically focused at the processing point. Then, the optical system 6 of the laser light irradiation section is adjusted.

Then, in step S20, the driving mechanism 4 is driven so that the processing start point of the workpiece 2 is the condenser lens 6.
The XY table 3 is moved so as to be directly below (1) and 6 (2).

Then, in step S21, an optical shutter (not shown) in the optical system 6 of the laser light irradiation section is opened.

Next, in step S22, the motion programs previously stored in the internal memory of the motion controller (not shown) of the laser processing apparatus 1 are sequentially read.

At this time, in step S23, the motion program read from the motion controller is executed. When the motion program is executed, the condensing lens 6 (1),
6 (2), the XY table 3 is moved so that the processing points of the work piece 2 are sequentially located underneath, and each time the XY table 3 is moved, the laser light is intermittently emitted from the laser light irradiation unit. Laser processing is performed according to the motion program by projecting onto the processing points of 2.

After the motion program is completely executed, the optical shutter in the optical system 6 is closed in step S24.

Here, in step S25, the laser processing apparatus 1 returns from the laser processing orthogonal coordinate system to the alignment orthogonal coordinate system.

Thereafter, in step S26, the drive mechanism 4 is driven to move to a position (workload unloading position) for taking out the workpiece 2 on the XY table 3.

Then, in step S27, the workpiece 2 is taken out on the XY table 3.

At this time, in the laser processing apparatus 1,
When it is necessary to perform laser processing on another workpiece 2, it is not necessary to perform laser processing on another workpiece 2 by returning to step S4 and performing the processing after step S4 again. At this time, the processing according to this series of flowcharts is ended.

By the way, it is preferable that one alignment mark 11 is provided on each of the two sides of the workpiece 2 and that the shape of the alignment mark 11 is a small round shape. However, the positions where the alignment marks 11 are provided do not have to be provided on both sides of the work piece 2 as long as they are spaced apart from each other, and the number thereof does not have to be two if it is plural. The shape of the alignment mark 11 is not limited to a small round shape, and may be a small triangle or a square.

The workpiece 2 is not limited to the color filter used in the liquid crystal display section, and it is needless to say that the workpiece 2 may be another one as long as it can perform high precision fine laser processing. is there.

Further, the drive mechanism 4 is preferably a linear motor, but may be any other drive mechanism as long as it can move the XY table 3 at high speed and with high precision.

[0050]

As described in detail above, according to the present invention, at least two alignment marks 11 are provided on the workpiece 2 and the positions of these alignment marks 11 are roughly adjusted by the mark detection units 7 to 9. Since the detection and the subsequent fine adjustment detection are performed, and the alignment is adjusted based on the detection result so that the placement position of the workpiece 2 matches the predetermined processing position, the shape of the workpiece 2 is As in the case of slightly different for each work piece 2 or when manufacturing a color filter or the like used in a liquid crystal display unit,
Even when performing high-precision fine laser processing of the workpiece 2, if at least two alignment marks 11 provided on the workpiece 2 can be detected, the XY of the workpiece 2 is detected.
There is an effect that the placement position on the table 3 can be adjusted so as to match the predetermined laser processing position.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a laser processing apparatus provided with an alignment mechanism of the present invention.

FIG. 2 is a configuration diagram showing a mark detection unit in the laser processing apparatus shown in FIG.

FIG. 3 is a flowchart showing an operation process when carrying out alignment adjustment and subsequent laser processing in the laser processing apparatus provided with the alignment mechanism of the present invention.

[Explanation of symbols]

 1 Laser Processing Device 2 Workpiece 3 XY Table 4 Drive Mechanism 4X (1) Horizontal Axis Linear Motor Yoke 4X (2) Horizontal Axis Rail 4Y (1) Vertical Axis Linear Motor Yoke 4Y (2) Vertical Axial rail 5 Laser oscillator 6 Optical system 6 (1), 6 (2) Condensing lens 7 CCD camera for coarse adjustment 8 CCD camera for fine adjustment 9 Lens barrel 9 (1), 9 (2) Reflector 9 (3 ) Optical fiber 10 Surface plate 10 (1) Anti-vibration foot 11 Alignment mark 12 Position adjustment plate 13 Objective lens 14 Height direction position adjustment motor

Claims (7)

[Claims] 1. A work piece is placed and X is driven by a drive mechanism.
XY that can slide freely in the (horizontal axis) direction and the Y (vertical axis) direction
A table and a laser light irradiating unit for irradiating the workpiece with a laser beam derived from a laser oscillator through an optical system to perform laser processing on the workpiece, and at least 2 provided on the workpiece. A mark detection unit that sequentially performs fine adjustment detection after sequentially performing coarse adjustment detection of the positions of the two alignment marks, and the drive mechanism performs the XY adjustment based on the detection result of the mark detection unit.
A laser processing apparatus comprising: an alignment mechanism that slides a table to match a mounting position of the workpiece with a predetermined processing position. 2. The laser processing apparatus according to claim 1, wherein the mark detection unit includes a Z (height) direction adjustment unit for adjusting the position of the alignment mark. 3. The laser processing apparatus according to claim 1, wherein the alignment marks are provided one on each side of the workpiece. 4. The lens barrel that includes an objective lens facing the alignment mark, guides the reflected light from the alignment mark passing through the objective lens, and the alignment lens guided by the lens barrel. 3. The laser processing apparatus according to claim 1, further comprising a coarse adjustment camera and a fine adjustment camera that allow reflected light from the mark to enter. 5. The laser processing according to claim 2, wherein the Z (height) direction adjusting unit for adjusting the position of the alignment mark comprises a motor mechanism for moving the objective lens toward and away from the lens barrel. apparatus. 6. The laser processing apparatus according to claim 1, wherein the drive mechanism includes a linear motor. 7. The laser processing apparatus according to claim 1, wherein the object to be processed is a color filter used in a liquid crystal display section.