JP2003162068A - Laser drawing method and device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laser drawing method and its device which can improve the precision of laser drawing on a drawn body (printed wiring board S). <P>SOLUTION: The laser drawing device is equipped with a position correcting means of correcting a drawing start position according to the position shift quantity of a laser beam LB detected by a CCD camera 19 and the position shift quantity of the arrangement position of the CCD camera 19 detected by a 1st arrangement position detecting means comprising a 2nd correction pattern CR, the CCD camera 19, and a beam shift image processing part, so even if the arrangement position of the CCD camera 19 shifts owing to environmental changes, etc., the position shift quantity is detected and corrected and the laser drawing is carried out, so a decrease in laser drawing precision due to the phase shift of the CCD camera 19 itself can be eliminated, so that high-precision laser drawing can be performed. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser drawing method and apparatus for drawing a desired pattern on an object to be drawn by irradiating the object to be drawn such as a printed wiring board with a laser beam. The present invention relates to a technique for improving the accuracy of laser drawing on an object to be drawn.

[0002]

2. Description of the Related Art As a conventional apparatus of this type, for example, a laser drawing apparatus disclosed in Japanese Patent Application Laid-Open No. 10-227988 is known. This laser drawing device scans a drawing target mounted on a drawing table with a laser beam modulated based on raster data in the main scanning direction and in the sub-scanning direction orthogonal to the main scanning direction. By moving the, the object to be drawn is subjected to laser drawing. As a result, a desired pattern such as a circuit pattern is drawn on the entire drawing area of the drawing object.

Further, in the above-mentioned laser drawing apparatus, in order to solve the problem that the optical axis of the laser beam is changed due to temperature change and the like and the drawing position is shifted, the laser drawing apparatus has a laser beam in the drawing table. (CCD (charge coupled dev
ice) The camera is fixed. Then, the drawing start position data is corrected based on the positional deviation amount of the laser beam detected by the CCD camera.

[0004]

However, the conventional example having such a structure has the following problems. That is, in the conventional laser drawing apparatus, a CCD camera provided on the drawing table detects a change in the optical axis of the laser beam due to a temperature change or the like, that is, a positional deviation amount of the scanning position of the laser beam. Even if the drawing start position data is corrected on the basis of the positional deviation amount of the laser beam detected by the CCD camera, the drawing start position of the laser beam is not sufficiently corrected and laser drawing cannot be performed with high accuracy. There's a problem.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a laser drawing method and apparatus capable of improving the accuracy of laser drawing on an object to be drawn.

[0006]

[Means for Solving the Problems] In order to achieve the above-mentioned objects, the inventors of the present invention have earnestly studied and obtained the following findings. That is, not only the optical axis change of the laser beam occurs due to the temperature change or the like, but also the CCD camera (beam position) relative to the drawing table (holding means) due to the environmental change such as the temperature change in the laser drawing apparatus. It was clarified that there is also a phenomenon that the fixed position (arrangement position) of the detection means) changes. Thus, due to environmental changes, CCD
If the fixed position of the camera changes, the positional deviation amount of the scanning position of the laser beam cannot be accurately detected. Therefore, if the drawing start position data is corrected based only on the positional deviation amount of the laser beam detected by the CCD camera, the drawing They found a causal relationship that the starting position could not be corrected sufficiently.

The present invention based on such knowledge has the following configuration. That is, according to the first aspect of the invention, with respect to the beam scanning means for scanning the laser beam along the main scanning direction, the holding means for holding the object to be drawn is provided along the sub-scanning direction orthogonal to the main scanning direction. In a laser drawing method for drawing a desired pattern on an object to be drawn while relatively moving the moving means, a beam position detecting means for detecting a positional deviation amount of a laser beam emitted from the beam scanning means by a beam position detecting means. And a first arrangement position detecting step of detecting an amount of positional deviation of the arrangement position of the beam position detecting means, the positional deviation amount of the laser beam detected in the beam position detecting step, and the first arrangement position detecting step. It is characterized in that the drawing start position is corrected based on the positional deviation amount of the beam position detecting means detected in the arrangement position detecting step.

The invention described in claim 2 is the same as claim 1.
In the laser drawing method according to the item (1), a drawing object position detecting step of detecting a positional deviation amount of the drawing object held by the holding means by the drawing object position detecting means, and an arrangement position of the drawing object position detecting means. A second placement position detecting step of detecting the position shift amount of the laser beam, the position shift amount of the laser beam detected in the beam position detecting step, and the beam detected in the first placement position detecting step. Positional deviation amount of the position detecting means, positional deviation amount of the drawing object detected in the drawing object position detecting step, and position of the drawing object position detecting means detected in the second arrangement position detecting step It is characterized in that the drawing start position is corrected based on the shift amount.

According to a third aspect of the invention, with respect to the beam scanning means for scanning the laser beam along the main scanning direction, the holding means holding the object to be drawn is sub-scanning direction orthogonal to the main scanning direction. In a laser drawing apparatus that draws a desired pattern on a drawing object while relatively moving it along the moving means along with beam position detecting means for detecting the positional deviation amount of the laser beam emitted from the beam scanning means. A first arrangement position detecting means for detecting a positional deviation amount of the arrangement position of the beam position detecting means, a laser beam positional deviation amount detected by the beam position detecting means, and a first arrangement position detecting means Position correction means for correcting the drawing start position on the basis of the amount of positional deviation of the beam position detection means detected by the position correction means.

The invention described in claim 4 is the same as claim 3
In the laser drawing apparatus according to the paragraph (1), the drawing object position detecting means for detecting the positional deviation amount of the drawing object held by the holding means and the positional deviation amount of the arrangement position of the drawing object position detecting means are detected. A second arrangement position detection unit is further provided, and the position correction unit is configured to detect the position shift amount of the laser beam detected by the beam position detection unit and the first position.
Position deviation amount of the beam position detecting means detected by the arrangement position detecting means, the position deviation amount of the drawing object detected by the drawing object position detecting means, and the second arrangement position detecting means The drawing start position is corrected on the basis of the amount of positional deviation of the drawing object position detecting means.

Further, the invention described in claim 5 is the same as claim 3
Alternatively, in the laser drawing apparatus according to claim 4, the laser beam emitted from the beam scanning unit is fixed to the holding unit at a position where the laser beam is incident, and the laser beam emitted from the beam scanning unit is fixed. The beam position detecting means further comprises a calibration member having a first calibration pattern for calibrating the position, and the beam position detecting means images the laser beam incident on the first calibration pattern of the calibration member. An image pickup means is provided, and a positional deviation amount of the laser beam with respect to the holding means is detected based on the image data obtained by the first image pickup means,
The arrangement position detection means of the arrangement position of the beam position detection means with respect to the holding means based on the image data obtained by imaging the first calibration pattern of the calibration member by the first imaging means. The feature is that the amount of displacement is detected.

The invention according to claim 6 is the same as claim 4
In the laser drawing apparatus according to the item (1), the position of the laser beam emitted from the beam scanning unit is fixed to the holding unit and the position of the laser beam emitted from the beam scanning unit is calibrated. And a second calibration pattern for calibrating the arrangement position of the drawing object position detection means with respect to the holding means.
Further comprising a calibration member having a calibration pattern, wherein the beam position detection means holds the holding unit based on image data obtained by imaging the laser beam incident on the first calibration pattern of the calibration member. Detecting the positional deviation amount of the laser beam with respect to the means, the first arrangement position detecting means, based on the image data obtained by imaging the first calibration pattern of the calibration member by the beam position detecting means, The drawing object position detecting means detects a positional deviation amount of an arrangement position of the beam position detecting means with respect to the holding means, and the drawing object position detecting means has a second imaging means for picking up an image of the drawing object held by the holding means. Based on the image data obtained by the second image pickup means, the displacement amount of the object to be drawn with respect to the holding means is detected, and the second arrangement position detection means is the second calibration pattern of the calibration member. Based on the second image data obtained by imaging by the imaging means, it is characterized in detecting the positional deviation amount of the arrangement position of the drawing member position relative to the holding means.

The invention according to claim 7 is the same as claim 5
Alternatively, in the laser drawing apparatus according to claim 6, at least a region of the calibration member on which the first calibration pattern is formed is a transparent member that transmits the laser beam emitted from the beam scanning unit. The calibration member is arranged between the beam scanning unit and the first imaging unit.

The invention described in claim 8 is the invention according to claim 5.
8. The laser drawing apparatus according to claim 7, wherein the laser beam from the beam scanning means is used for the first laser beam.
When the image is captured by the image capturing unit, the light emitting unit further includes a dimming unit that is disposed between the beam scanning unit and the first image capturing unit and that dims the laser beam incident on the first image capturing unit. It is a feature.

The invention described in claim 9 is the same as claim 5
9. The laser drawing apparatus according to claim 7, wherein at least the region of the calibration member on which the first calibration pattern is formed is a member that attenuates the incident laser beam. It is a thing.

According to a tenth aspect of the invention, in the laser drawing apparatus according to any one of the fifth to ninth aspects, when the first calibration pattern is imaged by the first image pickup means. , At least a first of said calibration members
It is characterized by further comprising an illuminating means for illuminating the area in which the calibration pattern is formed.

The invention described in claim 11 is the laser drawing apparatus according to any one of claims 5 to 10, wherein the first imaging means scans the laser beam by the beam scanning means. Is provided near both ends of the main scanning area.

[0018]

The operation of the invention described in claim 1 is as follows. In the beam position detecting step, the positional deviation amount of the laser beam emitted from the beam scanning means is detected by the beam position detecting means. In the first arrangement position detecting step, the amount of positional deviation of the arrangement position of the beam position detecting means is detected. Then, the drawing start position is corrected based on the positional deviation amount of the laser beam detected in the beam position detecting step and the positional deviation amount of the beam position detecting means detected in the first arrangement position detecting step. Therefore, laser drawing is performed on the object to be drawn at the accurate drawing start position in which the positional deviation of the arrangement position of the beam position detecting means and the positional deviation of the laser beam are corrected.

According to the second aspect of the invention, in the drawing object position detecting step, the drawing object position detecting means detects the positional deviation amount of the drawing object held by the holding means. In the second arrangement position detecting step, the amount of positional deviation of the arrangement position of the drawing object position detecting means is detected. Then, the positional deviation amount of the laser beam detected in the beam position detecting step, the positional deviation amount of the beam position detecting means detected in the first arrangement position detecting step, and the object detected in the drawing object position detecting step. The drawing start position is corrected based on the positional deviation amount of the drawing object and the positional deviation amount of the drawing object position detection means detected in the second arrangement position detection step. Therefore, more accurate drawing is performed by correcting the positional deviation of the arrangement position of the beam position detecting means, the positional deviation of the laser beam, the positional deviation of the object to be drawn, and the positional deviation of the arrangement position of the object to be drawn position detecting means. Laser drawing is performed on the object to be drawn at the start position.

According to the third aspect of the invention, the beam position detecting means detects the amount of positional deviation of the laser beam emitted from the beam scanning means. The first arrangement position detecting means detects a positional deviation amount of the arrangement position of the beam position detecting means. The position correcting unit corrects the drawing start position based on the amount of positional deviation of the laser beam detected by the beam position detecting unit and the amount of positional deviation of the beam position detecting unit detected by the first arrangement position detecting unit. To do.
Therefore, laser drawing is performed on the object to be drawn at the accurate drawing start position in which the positional deviation of the arrangement position of the beam position detecting means and the positional deviation of the laser beam are corrected.

According to the fourth aspect of the invention, the drawing object position detecting means detects the amount of positional deviation of the drawing object held by the holding means. The second arrangement position detecting means is
A displacement amount of the arrangement position of the drawing object position detection means is detected. The position correcting means detects the positional deviation amount of the laser beam detected by the beam position detecting means, the positional deviation amount of the beam position detecting means detected by the first arrangement position detecting means, and the drawing object position detecting means. The drawing start position is corrected on the basis of the positional deviation amount of the drawn object and the positional deviation amount of the drawing object position detecting unit detected by the second arrangement position detecting unit. Therefore, more accurate drawing is performed by correcting the positional deviation of the arrangement position of the beam position detecting means, the positional deviation of the laser beam, the positional deviation of the object to be drawn, and the positional deviation of the arrangement position of the object to be drawn position detecting means. Laser drawing is performed on the object to be drawn at the start position.

According to the invention of claim 5, the calibration member has a first calibration pattern for calibrating the position of the laser beam emitted from the beam scanning means. It is fixed to the holding means at a position where the laser beam emitted from the scanning means can enter. The beam position detection means has a first imaging means for imaging the laser beam incident on the first calibration pattern of the calibration member, and holds it based on the image data obtained by this first imaging means. The amount of positional deviation of the laser beam with respect to the means is detected. The first disposition position detecting means displaces the disposition position of the beam position detecting means with respect to the holding means based on the image data obtained by imaging the first calibration pattern of the calibration member by the first imaging means. Detect the amount. Therefore, the laser drawing is performed on the object to be drawn at the accurate drawing start position in which the positional deviation of the position of the beam position detecting means with respect to the holding means and the positional deviation of the laser beam with respect to the holding means are corrected.

According to the sixth aspect of the present invention, the calibration member is the first calibration pattern for calibrating the position of the laser beam emitted from the beam scanning means and the object to be drawn with respect to the holding means. It has a second calibration pattern for calibrating the arrangement position of the position detecting means, and is fixed to the holding means at a position where the laser beam emitted from the beam scanning means can enter. The beam position detecting means detects the positional deviation amount of the laser beam with respect to the holding means based on the image data obtained by imaging the laser beam incident on the first calibration pattern of the calibration member.
The first arrangement position detection means is based on image data obtained by imaging the first calibration pattern of the calibration member with the beam position detection means, and the positional displacement amount of the arrangement position of the beam position detection means with respect to the holding means. To detect. The drawing object position detecting means has a second imaging means for picking up an image of the drawing object held by the holding means, and the drawing object of the drawing object with respect to the holding means is based on the image data obtained by the second imaging means. The amount of displacement is detected. The second placement position detection means shifts the placement position of the drawing target position with respect to the holding means based on the image data obtained by imaging the second calibration pattern of the calibration member by the second imaging means. Detect the amount. Therefore, the positional deviation of the position of the beam position detection means with respect to the holding means, the positional deviation of the laser beam with respect to the holding means, the positional deviation of the object to be drawn with respect to the holding means, and the position of the object position detection means with respect to the holding means The laser drawing is performed on the object to be drawn at the accurate drawing start position in which the positional deviation of 1 is corrected.

According to the invention described in claim 7, at least the region of the calibration member on which the first calibration pattern is formed is transmissive for transmitting the laser beam emitted from the beam scanning means. The calibration member, which is a member, is disposed between the beam scanning unit and the first imaging unit. Therefore, by detecting the laser beam emitted from the beam scanning means and transmitted through the area of the first calibration pattern of the calibration member, the positional deviation of the laser beam with respect to the holding means can be detected.

According to the eighth aspect of the invention, the dimming means includes the beam scanning means and the first imaging means when the laser beam from the beam scanning means is imaged by the first imaging means. The laser beam incident on the first image pickup means is dimmed.

According to the invention described in claim 9, since at least the region of the calibration member on which the first calibration pattern is formed is a member for dimming the incident laser beam, the beam scanning means is provided. The laser beam from is transmitted through the area of the first calibration pattern of the calibration member, is dimmed, and is incident on the beam position detection means.

According to the invention described in claim 10,
The illuminating means illuminates at least a region of the calibrating member in which the first calibrating pattern is formed when the first calibrating means captures the first calibrating pattern. The calibration pattern is imaged by the beam position detecting means.

Further, according to the invention of claim 11,
The first image pickup means is provided near both ends of the main scanning area of the laser beam scanned by the beam scanning means. Therefore, the positional deviation of the laser beam near the main scanning start position and near the main scanning end position is detected.

[0029]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing a schematic configuration of an example of a laser drawing apparatus according to the present invention, FIG. 2 is a plan view thereof, and FIG. 3 is a side view thereof.

As shown in FIG. 1, the laser drawing apparatus includes a drawing stage 5 on which a printed wiring board (object to be drawn) S to which a photosensitive material is applied is placed, and a drawing laser beam LB.
Polygon mirror 9 for deflecting the beam in the main scanning direction (x direction)
4, a beam scanning mechanism 21 including an fθ lens 95, and the like,
A moving mechanism for moving the drawing stage 5 in the sub-scanning direction (y direction) is provided.

The moving mechanism of the drawing stage 5 is constructed as follows. A pair of guide rails 3 are arranged on the upper surface of a base 1 of this apparatus, and a feed screw 9 rotated by a servomotor 7 is arranged between the guide rails 3. The drawing stage 5 is screwed onto the feed screw 9 at its lower portion. As shown in FIG. 3, the drawing stage 5 includes a stage base 10 to which a feed screw 9 is screwed and which is slidably mounted along a guide rail 3, and a rotation for rotating the stage around a vertical z-axis. Mechanism 11 and lifting mechanism 13 for lifting in the vertical z direction
And the mounting table 15 for sucking and mounting the printed wiring board S on the uppermost part.

The drawing stage 5 described above corresponds to the holding means in the present invention, and includes the above-mentioned guide rail 3 and
A moving mechanism composed of the servo motor 7 and the feed screw 9 corresponds to the moving means in the present invention.

In the y direction (sub scanning direction) in which the drawing stage 5 is driven by the servo motor 7, the processing position P is set.
A beam scanning mechanism 21 for irradiating the drawing laser beam LB downward while irradiating the drawing laser beam LB in the x direction (main scanning direction) is provided. The beam scanning mechanism 21 is arranged on the upper part of the base 1 by a gate-shaped frame, and when the servo motor 7 is driven, the drawing stage 5 moves back and forth with respect to the beam scanning mechanism 21. .

Next, the beam scanning mechanism 21 will be described with reference to FIG. The laser light source 81 is, for example, a solid-state laser having a wavelength of 532 nm using a semiconductor as an excitation light source. Laser beam LBa emitted from this laser light source 81
Is changed in direction by 90 ° by the corner mirror 82 and is incident on the beam expander 83. The laser beam LBa adjusted to have a predetermined beam diameter by the beam expander 83 is divided into, for example, eight laser beams LBb by the beam splitter 84 (omitted in FIG. 1). The laser beam LBb divided into eight beams is respectively collected by a condensing lens 85 and a corner mirror 86, and an acousto optical modulator.
(modulator: AOM) 87, and is imaged in the crystal inside the acousto-optic modulator 87, and each is independent by a control signal from a main scanning control circuit 57 (see FIG. 8) described later. Are modulated based on the drawing signal.

The laser beam LBc modulated by the acousto-optic modulator 87 is reflected by the corner mirror 88 and enters the relay lens system 89. The laser beam LBc emitted from the relay lens system 89 is guided to the polygon mirror 94 via the cylindrical lens 90, the corner mirror 91, the spherical lens 92, and the corner mirror 93. Then, a linear spot that is long in the main scanning direction (x direction) is formed on each surface of the polygon mirror 94.

The linear laser beam LBc deflected and scanned in the horizontal plane by the rotation of the polygon mirror 94 is fθ.
After passing through the lens 95, it is folded back in the main scanning direction by a long folding mirror 96. Then, the field lens 9 is set so that the incident angle on the exposure surface becomes almost vertical.
After being corrected in 7, the irradiation is performed toward the mounting table 15 through the cylindrical lens 98. The cylindrical lens 98 is long in the main scanning direction and has power only in the sub scanning direction.

The linear spot on the polygon mirror 94 described above includes an fθ lens 95, a field lens 97, and
By the action of the cylindrical lens 98, a spot having a predetermined diameter is formed on the mounting table 15 to form an image, and the polygon mirror 94 rotates to move the laser beam LB (maximum 8) in the main scanning direction (x direction). Book laser beam).

A mirror 100 for guiding the laser beam LB to the start sensor 99 is arranged between the field lens 97 and the cylindrical lens 98 described above, as shown in FIG. The mirror 100 reflects the laser beam LB that has passed through the field lens 97 and immediately before the drawing start position so as to be guided obliquely upward where the start sensor 99 is arranged. The timing pulse output from the start sensor 99 is applied to a main scanning control circuit 57 (see FIG. 8) described later, and drawing is started after a predetermined time from that point.

The cylindrical lens 98 is arranged with its cylindrical surface facing upward. Position correction mechanisms 101 for moving the cylindrical lens 98 in the sub-scanning direction (y direction) are provided at both ends of the cylindrical lens 98, respectively. Cylindrical lens 98
It is possible to move the scanning position itself by independently moving the position of 8 in the sub-scanning direction (y direction).

The beam scanning mechanism 21 described above corresponds to the beam scanning means in the present invention.

Next, the mounting table 15 will be described with reference to FIGS. 4 is a partial cross-sectional view of the mounting table 15, FIG. 5 is a partial plan view of the mounting table 15, and FIGS. 6A and 6B show the CCD camera 19 for the first calibration pattern CR. It is a figure which shows the imaged image and FIG.
FIG. 2 is a schematic side view for explaining a peripheral configuration of a CCD camera 19 of the laser drawing device shown in FIG.

That is, as shown in FIG. 4, the reference mask RM is provided on the upper surface of the base 15a of the mounting table 15, and the suction table 17 is provided thereon. As shown in FIG. 5, a lattice-shaped second calibration pattern PR is formed on the entire upper surface of the reference mask RM except for the peripheral portion. It may be formed only in the movable range of 39. The second calibration pattern PR on the reference mask RM has, for example, a line width of 50 μm and a width of 5 mm.
It is formed at intervals.

On the upper surface of the suction table 17, the second lower
The suction groove 17a is formed at a position that does not overlap with the calibration pattern PR in plan view. A vacuum suction source (not shown) is connected to the suction groove 17a, and the lower surface of the printed wiring board S placed on the upper surface is sucked and held through the suction groove 17a. In this embodiment, both the reference mask RM and the suction table 17 described above are formed of transparent glass, and irradiation light from a backlight (not shown) built in the base 15a of the lowermost layer is applied to the printed wiring board S. The reference hole SR is configured to be illuminated and exposed.

As shown in FIGS. 5 and 7, the reference mask RM
On the upper surface of the peripheral portion on the side far from the beam scanning mechanism 21, two first calibration patterns CR are provided in the main scanning direction (x
Direction) is formed at intervals. One of the first calibration patterns CR is located near the main scanning start position of the laser beam LB, and the other of the first calibration patterns CR.
Is located near the main scanning end position of the laser beam LB.

As shown in FIG. 6 (a), the first calibration pattern CR adopts, for example, a double girder shape consisting of four lines L. The double girder is formed by arranging two lines L parallel to the y direction with an interval Wx and arranging two lines L parallel to the x direction with an interval Wy. The central portion of the double girder, that is, the portion surrounded by the four lines L is a laser so that the lines L do not interfere with the laser beam LB when detecting the positional deviation of the laser beam LB. It is made larger than the spot diameter of the beam LB. The first calibration pattern CR located near the main scanning start position of the laser beam LB has coordinates (X0, Y) of the reference mask RM.
0), the first calibration pattern CR located near the main scanning end position of the laser beam LB is the reference mask RM.
Is formed at the position of coordinates (Xn, Y0). In addition,
The reference mask RM described above corresponds to the calibration member in the present invention.

As shown in FIGS. 4, 5, and 7, the first calibration pattern C on the base 15a of the mounting table 15 is used.
A CCD camera 19 capable of measuring the position of the exposure spot of the laser beam LB is fixed at a position corresponding to R, that is, a position below the first calibration pattern CR on the base 15a. A CCD camera 19 is fixed to a position below each of the two first calibration patterns CR on the mounting table 15 shown in FIG.
The CCD camera 19 described above is the first one in the present invention.
Corresponds to the image pickup means.

As shown in FIG. 7, in the vicinity of the first calibration pattern CR on the base 15a of the mounting table 15, a bending portion 74a is hung vertically in the z direction and the mounting table 15 is mounted. A filter support portion 74 is provided that is bent toward the upper position of the first calibration pattern CR so as to be parallel to the surface. The bent portion 74a is provided with an ND filter (neutral density filter) 75 for reducing the light amount of the laser beam LB. When measuring the position of the exposure spot of the laser beam LB, the drawing stage 5 is moved to the processing position PY by the driving of the servo motor 7, and the laser beam LB from the beam scanning mechanism 21 receives the ND filter 75 and the first beam. The light enters the CCD camera 19 via the calibration pattern CR. In this way, if the exposure spot of the laser beam LB is directly input to the CCD camera 19, the light amount becomes excessive, so the ND filter 75 provided on the upper part of the CCD camera 19 reduces the light amount to an appropriate amount. The filter support portion 74 and the ND filter 75 described above correspond to the dimming means in the present invention.

By providing the ND filter 75 between the beam scanning mechanism 21 and the CCD camera 19, the laser beam LB can be dimmed and input to the CCD camera 19. More preferably, the ND filter 75 should be provided between the beam scanning mechanism 21 and the reference mask RM. In this case, when imaging the laser beam LB, the laser beam LB is dimmed and the CCD camera 19
To the first calibration pattern CR with the CCD camera 19 and the first calibration pattern CR is not dimmed.
There is an advantage that the calibration pattern CR of 1 does not become dark. That is, when the ND filter 75 is provided between the reference mask RM and the CCD camera 19, the first calibration pattern CR becomes dark.

Further, as shown in FIG. 7, the side of the base 1 far from the beam scanning mechanism 21 (the left end side of the paper surface of FIG. 7).
Includes a pillar portion 76a vertically extending in the z direction and the pillar portion 76a.
A lamp support member 76 including a protrusion 76b protruding from the upper side of a so as to be parallel to the mounting surface of the mounting table 15 and a transillumination lamp 77 provided on the protrusion 76b is provided. There is. When the drawing stage 5 is moved to the standby position by the driving of the servomotor 7, the transmitted illumination lamp 7 is provided between the ND filter 75 of the filter support portion 74 and the first calibration pattern CR of the drawing stage 5.
7 is positioned, the light from the transillumination lamp 77 is applied to the first calibration pattern CR of the drawing stage 5, and FIG.
As shown in, the CCD camera 19 is adapted to image the first calibration pattern CR. The transillumination lamp 77 described above corresponds to the illumination means in the present invention.

As shown in FIG. 3, an elevating mechanism 13 for elevating the drawing stage 5 in the z direction is provided at the lower part of the base 15a, and an inclined member 13a whose upper surface is inclined.
And a screw shaft 13b screwed together, and a pulse motor 13c for rotationally driving the screw shaft 13b. The free wheel attached to the lower surface of the base 15a moves forward and backward in the y direction by driving the pulse motor 13c.
As it is moved up and down on the inclined surface of a, it is moved up and down in the z direction along a guide rail (not shown).

An alignment scope unit 31 is arranged on the base 1 so as to cover the drawing stage 5 located at the standby position, as shown in FIGS. The alignment scope unit 31 includes four alignment scopes 33, 3 that can move independently in a horizontal plane.
5, 37, 39 are provided. Each of the alignment scopes 33, 35, 37, 39 has a CCD camera 33a, 35
a, 37a, 39a and lens portions 33b, 35b, 37
b, 39b.

The alignment scope unit 31 is provided with a scope stage 41 standing on the base 1, a left stage 43 having the alignment scopes 33 and 39 mounted thereon and a right stage 45 having the alignment scopes 35 and 37 mounted thereon. It has and. The left stage 43 is
Linear guide 41 arranged on scope stage 41
It is fitted slidably in the x direction on a and is screwed onto a feed screw 41c rotated by a pulse motor 41b. A linear guide 43a is arranged in the y direction on the upper part thereof, and a moving block 43b to which an alignment scope 39 is attached is fitted to the linear guide 43a. The moving block 43b is screwed onto a feed screw 43d rotated by a pulse motor 43c. Therefore, when the pulse motor 41b is driven, the alignment scopes 33 and 39 are moved together with the left stage 43 in the x direction, and when the pulse motor 43c is driven, the alignment scope 33 provided on the linear guide 43a is It does not move, only the alignment scope 39 is y
It is designed to be moved in the direction. Note that when a pulse motor (not shown) for moving the alignment scope 33 in the y direction is driven, the alignment scope 39 does not move, and only the alignment scope 33 moves in the y direction. .

The right stage 45 is the scope stage 41.
The linear guide 41a provided above is slidably mounted in the x direction, and is screwed to a feed screw 41e rotated by a pulse motor 41d. A linear guide 45a is provided on the upper part thereof, and a moving block 45b to which an alignment scope 37 is attached is mounted on the linear guide 45a. The moving block 45b is a pulse motor 45.
It is screwed onto the feed screw 45d rotated by c. Therefore, when the pulse motor 41d is driven,
While the alignment scopes 35 and 37 are moved in the x direction together with the right stage 45, when the pulse motor 45c is driven, only the alignment scope 37 is moved independently by y.
Is moved in the direction. When a pulse motor (not shown) for moving the alignment scope 35 in the y direction is driven, the alignment scope 37 does not move and only the alignment scope 35 moves in the y direction. .

Next, refer to the block diagram of FIG. Figure 8
FIG. 3 is a block diagram showing a configuration of a control system of the laser drawing device. Each alignment scope 33, 35, 37, 39
The CCD cameras 33a, 35a, 37a, 39a are all connected to the alignment image processing unit 50a of the image processing unit 49. The alignment image processing unit 50a processes each video signal, calculates the position of the center of gravity, and aligns each of the alignment scopes 33, 35 with respect to the second calibration pattern PR.
"Alignment scope displacement amount", which is the displacement amount of the arrangement positions of 37 and 39, and the second calibration pattern P
The amount of positional deviation of the printed wiring board S with respect to R is calculated. CCD camera 3 described above
3a, 35a, 37a, 39a correspond to the second image pickup means of the present invention.

The CCD cameras 19 for measuring the positions of the exposure spots of the laser beam LB are all image processing units 4.
It is connected to the beam shift image processing unit 50b of FIG. 9 where each video signal is processed and the "beam position shift amount" and "CCD camera position shift amount" are calculated. The CCD camera 19 and the beam shift image processing unit 50b described above correspond to the beam position detecting means of the present invention and the first arrangement position detecting means of the present invention.

Further, the image processing section 49 displays a keyboard 51 for instructing the start of processing, images captured by the alignment scopes 33, 35, 37 and 39 and images captured by the CCD camera 19. A CRT 53 for displaying processing contents and the like is connected.

The system control unit 55 controls the entire apparatus. Here, the main scanning control circuit 57
The sub-scanning control circuit 59 and the calibration data storage unit 61 are connected to each other.

The raster conversion circuit 63 uses a CAD (Comput
er Aided Design), the run length data for raster scanning drawing converted from the artwork data of the printed wiring board is converted into raster data and sequentially output to the main scanning control circuit 57.

At the time of drawing, the system control unit 55 sets the main scanning control circuit 57 for setting the position of the laser beam LB in the x direction on the basis of the raster data sequentially sent from the raster conversion circuit 63 to the main scanning control circuit 57. To control. The main scanning control circuit 57 uses the beam scanning mechanism 2 based on the instruction from the system control unit 55 and the raster data.
Control 1

The sub-scanning control circuit 59 controls the laser beam LB.
The servomotor 7 is driven based on the clock pulse generated according to the main scanning of. This allows the drawing stage 5
Are moved in the y direction (sub-scanning direction). The moving position is detected by a sensor that detects an optical signal from a Y linear scale (not shown), is converted into a signal according to the moving position, and is given to the system control unit 55. The system control unit 55 feeds back the drive of the servo motor 7 according to the signal.

The calibration data storage unit 61 stores the reference mask RM.
When the drawing stage 5 provided in the lower layer of the suction table 17 is moved to the standby position (see FIG. 7), the video signals from the two CCD cameras 19 arranged on the drawing stage 5 are transferred to the image processing unit 49. The “CCD camera position shift amount”, which is the shift amount between the center position of each CCD camera 19 obtained by processing by the beam shift image processing unit 50b and the center position of the first calibration pattern CR, and each alignment scope. The alignment scopes 33, 35, which are obtained by processing the video signals from 33, 35, 37, 39 by the alignment image processing unit 50a of the image processing unit 49.
“Alignment scope position shift amount”, which is the shift amount between the center position of 37, 39 and the intersection point position of the second calibration pattern PR, and each alignment scope 33, 35, 3
The position of the board, which is the amount of deviation between the intersection of the printed wiring board S and the second calibration pattern PR, which is obtained by processing the video signals from 7, 39 by the alignment image processing section 50a of the image processing section 49. The amount of deviation ”is stored.

Further, the calibration data storage unit 61 moves the drawing stage 5 to the beam shift detection position (processing position PY) so that the two CCD cameras 19 fixed to the drawing stage 5 receive the laser beam LB. When (see Figure 7)
In addition, the center position of the exposure spot of the laser beam captured by each CCD camera 19 obtained by processing the video signals from the two CCD cameras 19 by the beam shift image processing unit 50b of the image processing unit 49 and the CCD camera. The "beam position shift amount", which is the shift amount from the center of the visual field 19, is also stored.

The system control section 55 uses the "CCD
The main scanning control circuit 57 is controlled so as to correct these positional deviations based on "camera positional deviation", "beam positional deviation", "alignment scope positional deviation", and "substrate positional deviation". To do. That is, the drawing start position is corrected. The system control unit 55, the main scanning control circuit 57, and the calibration data storage unit 61 described above correspond to the position correcting means in the present invention. (In the drawing start position correction, the servo motor 7 is not controlled in its speed or the like.)

Here, the "drawing start position" will be described. The "drawing start position" is the drawing start end of each scanning line along the main scanning direction. The main scanning control circuit 57, which has received the timing pulse output from the start sensor 99, starts drawing after a predetermined time from that point, so that the X direction position of the drawing start position is determined by the predetermined time. Therefore, the correction of the drawing start position in the X direction is performed by the main scanning control circuit 57 changing the predetermined time based on an instruction from the system control unit 55.

The Y direction position of the drawing start position is the drawing stage 5 detected by a Y linear scale (not shown).
It is decided based on the position of. That is, the drawing is started when the drawing stage 5 reaches the desired position. Therefore, the correction of the drawing start position in the Y direction is performed by the main scanning control circuit 57 changing the drawing start timing based on an instruction from the system control unit 55 to change the desired position. Separately from this, the main scanning control circuit 57 may move the cylindrical lens 98 by the position correction mechanism 101 based on an instruction from the system control unit 55 to change the Y direction position of the drawing start position.

First, the "positional displacement amount of the CCD camera" will be described more concretely with reference to FIG. In the initial mounting state, as shown in FIG.
The visual field center C of the visual field image V captured by the CCD camera 19 mounted on the base 15a of the mounting table 15 so as to look up at the first calibration pattern CR and the center point of the first calibration pattern CR (broken line). The CCD camera 19 is fixed to the mounting table 15 such that the CCD camera 19 coincides with the intersection point of.

The "amount of displacement of the CCD camera" is obtained as follows. As shown in FIG. 6B, the visual field center C of the visual field image V captured by the CCD camera 19 fixed to the base 15a of the mounting table 15 and the first calibration pattern CR.
The deviation from the center point of is determined in the x direction (Δx) and the y direction (Δy). As shown in FIG. 6B, the center point of the first calibration pattern CR is in the x direction (Δ
x) and y direction (Δy) are deviated. At this time, the "amount of displacement of the CCD camera" is "0" in both xy directions.
In the case of, the center point of the first calibration pattern CR and the visual field center C coincide with each other as shown in FIG. The above-mentioned Δ is stored in the calibration data storage unit 61 described above.
Store x and Δy. That is, even if the fixed position of the CCD camera 19 is displaced for some reason,
With reference to the first calibration pattern CR of the reference mask RM, which is position-invariant by design, the amount of deviation from that position is stored. Therefore, if this "positional displacement amount of the CCD camera" is read and corrected by that amount, the CCD camera 1
The actual position at the center C of the visual field 9 is accurately known.

Next, the "positional deviation amount of the alignment scope" will be described more concretely with reference to FIG.
FIG. 9 is a diagram showing an image obtained by capturing the second calibration pattern PR with the CCD camera 39a of the alignment scope 39.

For example, CC of the alignment scope 39
The deviation between the visual field center C of the visual field image V captured by the D camera 39a and the central point of the second calibration pattern PR at a predetermined position is x.
The direction (Δx) and the y direction (Δy) are obtained. In this case, when the “alignment scope displacement amount” is “0” in both the xy directions, the intersection of the second calibration pattern PR in FIG. 9 and the visual field center C coincide. The above-mentioned Δ is stored in the calibration data storage unit 61 described above.
Store x and Δy. In other words, alignment scope 39
The second calibration pattern P of the reference mask RM (having the first calibration pattern CR) whose position is invariant by design even if the position of is shifted for some reason.
With R as a reference, the amount of deviation from that position is stored. Therefore, this "alignment scope displacement"
Is read and corrected by that amount, the actual position at the center C of the visual field of the alignment scope 39 can be accurately known.

Further, as shown in FIG. 8, the drive section 65 of each alignment scope 33, 35, 37, 39 is provided corresponding to each alignment scope 33, 35, 37, 39. Since only the pulse motors are different, the alignment scope 33 will be described as an example. The drive unit 65 includes a drive circuit 65a that controls the pulse motor 41b based on an instruction from the system control unit 55. It should be noted that in FIG. 8, blocks of the driving units other than the alignment scope 33 are omitted.

The elevation control circuit 67 controls the elevation of the mounting table 15 in the z direction. System control unit 5
Reference numeral 5 controls the rotation of the pulse motor 13c via the drive circuit 69 as will be described later. Pulse motor 1
The mounting table 15 is moved up and down by driving 3c, and the height at this time is detected by the height detection circuit 73 including a Z linear scale (not shown) and fed back to the system control unit 55.

The alignment scope unit 31 and the alignment image processing unit 50a described above correspond to the object position detecting means in the present invention, and the second calibration pattern PR and the alignment scope unit 3 described above are used.
1 and the alignment image processing unit 50a correspond to the second arrangement position detecting means in the present invention.

Next, the "amount of displacement of the substrate" will be described more concretely. The corresponding alignment scopes 33, 35, 37, 39 are positioned on the reference holes SR provided at the four corners of the printed wiring board S. CCD camera 33 of each alignment scope 33, 35, 37, 39
a, 35a, 37a, 39a, the displacement of the center of gravity obtained from the reference hole SR of each visual field image V and the visual field center of each visual field image V is obtained in the x direction (Δx) and the y direction (Δy). . In this case, when the “substrate displacement amount” is “0” in both the xy directions, the center of the visual field and the center of gravity of the reference hole SR coincide. The above-mentioned Δx and Δy are stored in the calibration data storage unit 61 described above. Therefore, the actual position of the printed wiring board S can be accurately known by reading this "substrate positional displacement amount" and correcting it.

Finally, regarding the "beam position deviation amount",
A more specific description will be given with reference to FIG. Figure 10
Shows the exposure spot of the laser beam LB on the CCD camera 1
It is a figure which shows the image imaged in 9.

Two CCDs fixed to the drawing stage 5
When the drawing stage 5 is moved to the beam shift detection position (processing position PY) so that the camera 19 receives the laser beam LB (see FIG. 7), the visual field center C of the visual field image V captured by the CCD camera 19 The deviation of the laser beam LB from the center point of the exposure spot is obtained in the x direction (Δx) and the y direction (Δy). The “beam position shift amount” at this time is xy
When both directions are “0”, the center point of the exposure spot of the laser beam LB in FIG. 10 and the center C of the visual field coincide. The above-mentioned Δx and Δy are stored in the calibration data storage unit 61 described above. That is, even if the position of the laser beam LB is displaced due to a temperature change or the like, the CCD camera 19 is position-calibrated by using the first calibration pattern CR of the reference mask RM, which is design-invariant as a reference. The deviation amount from the center C of the visual field is stored. Therefore, the actual position of the exposure spot of the laser beam LB can be accurately known by reading out this "beam position deviation amount" and correcting it.

Next, the position calibration processing in the laser drawing apparatus of this embodiment will be described with reference to the flowchart of FIG. FIG. 11 is a flowchart showing the position calibration process.

Step S1 The system controller 55 positions the drawing stage 5 at the standby position as shown by the solid line in FIG. System control unit 5
5 is a state in which the drawing stage 5 is at the standby position and operates the transillumination lamp 77 to operate the transillumination lamp 77.
The first calibration pattern CR is irradiated with light, and the CCD camera 19 is operated to capture an image of the first calibration pattern CR. By doing so, the visual field image V (image data) as shown in FIG. 6 is acquired.

Step S2 The beam shift image processing unit 50b obtains the "position shift amount of the CCD camera" from the field image V (image data) obtained by capturing the first calibration pattern CR with the CCD camera 19, and the system control unit. The data is stored in the calibration data storage unit 61 via 55. Note that these steps S1 and S2 are the first
This corresponds to the arrangement position detecting step.

Step S3 The system control unit 55 determines the printed wiring board S to be processed.
CAD data relating to the above is read from a computer (not shown).

Step S4 Based on the received CAD data, the system control unit 55 sets the alignment scopes 33, 35, 37, at positions corresponding to the positions of the reference holes SR of the printed wiring board S loaded in step S10 described later. 39 is moved to bring the second calibration pattern PR into the visual field. As a result, the intersection of the second calibration pattern PR at a predetermined position of the reference mask RM, although it is out of focus, is located in each field of view of the alignment scopes 33, 35, 37, 39.

Step S5 The system control unit 55 raises the mounting table 15 in the z direction through the elevation control circuit 67 to move the alignment scopes 33, 35, 37 and 39 to the second calibration pattern PR.
Focus on.

Step S6 The alignment image processing section 50a causes the view image V (image data) of each alignment scope 33, 35, 37, 39.
Image processing, the center C of the visual field and the second calibration pattern PR
With respect to the calibration pattern PR, that is, the “positional displacement amount of the alignment scope” which is the positional displacement amount of the alignment scopes 33, 35, 37, 39 with respect to the calibration pattern PR, and the calibration data is obtained via the system control unit 55. It is stored in the storage unit 61 (see FIG. 9). The above steps S3 to S6 correspond to the second arrangement position detecting step of the present invention.

Step S7 The system control unit 55, as shown by the chain double-dashed line in FIG.
The drawing stage 5 is moved to the beam deviation detection position (processing position PY) so that the two CCD cameras 19 fixed to the drawing stage 5 receive the laser beam LB. The system control unit 55 operates the beam scanning mechanism 21 to cause the laser beam LB from the beam scanning mechanism 21 to be emitted to the ND filter 75 to reduce the light amount, and
The CCD camera 19 captures an image of the exposure spot of the dimmed laser beam LB through the first calibration pattern CR.

Step S8 The beam shift image processing unit 50b determines the "beam position shift amount", that is, the visual field center of the visual field image V captured by the CCD camera 19, from the image data of the exposure spot of the laser beam LB taken by the CCD camera 19. The shift between C and the center point of the exposure spot of the laser beam LB is obtained in the x direction (Δx) and the y direction (Δy) and stored in the calibration data storage unit 61 via the system control unit 55. The steps S7 and S8 correspond to the beam position detecting step of the present invention.

The steps S1 to S8 described above may be performed at least when the apparatus is started up, when the type of substrate is changed, or when desired periodic diagnosis is performed, and it is necessary to be performed every time before the drawing operation. There is no. Following Step S9-
S12 is executed every drawing operation.

Step S9 The system controller 55 returns the drawing stage 5 to the standby position as shown by the solid line in FIG. 7, and moves the mounting table 15 raised in the above step S5 to the alignment scope 3
It is moved down in the Z direction to the standby position so as to move away from the focal positions of 3, 35, 37 and 39.

Step S10 As shown by the solid line in FIG. 7, the printed wiring board S is placed on the drawing stage 5 at the standby position by, for example, a loader (not shown), and the system control unit 55 causes the drawing stage 5 to move. The printed wiring board S is suction-held on the drawing stage 5 by vacuum suction.

Step S11 The alignment image processing section 50a obtains the "position shift amount" of the substrate S by each of the alignment scopes 33, 35, 37 and 39, and stores it in the calibration data storage section 61 via the system control section 55. . Specifically, the reference hole SR is imaged by each of the alignment scopes 33, 35, 37, 39, the center of gravity position of the reference hole SR is obtained, and the positional deviation amount between the center of gravity position and the center of the visual field is obtained to store the calibration data. Part 6
Store in 1. This positional deviation amount is corrected based on the positional deviation amount of the alignment scopes 33, 35, 37, 39. The main scanning control circuit 5 is based on this position shift amount.
7 and the beam scanning mechanism 21 are controlled. Further, the deviation of the substrate S in the θ direction obtained based on each center of gravity position is corrected by rotating the mounting table 15. The steps S9 to S11 correspond to the drawing object position detecting step of the present invention.

Step S12 The drawing process for scanning the substrate S with the laser beam LB is executed. Specifically, as shown by the two-dot chain line in FIG. 7, again,
After moving the drawing stage 5 to the beam deviation detection position, as shown by the solid line in FIG. 7, the drawing table 5 is moved from this position to the standby position while the laser beam is scanned. At this time, 4 shown in [1] to [4] below
The correction of the drawing start position is executed based on the two shift amounts.

[1] Alignment scopes 33 and 3 for the reference mask RM (second calibration pattern PR)
5, 37, 39 position deviation amount (calculated in step S6) [2] Position deviation amount of the substrate S with respect to the reference mask RM (second calibration pattern PR) (calculated in step S11) [3] Reference mask RM ( Positional deviation of CCD camera 19 with respect to first calibration pattern CR (calculated in step S2) [4] Positional deviation of laser beam LB with respect to reference mask RM (first calibration pattern CR) (calculated in step S8) )

As described above, according to the laser drawing apparatus of the present embodiment, the CC including the CCD camera 19 provided on the drawing stage 5 and the beam shift image processing section 50b is used.
Since the first arrangement position detecting means for detecting the amount of positional deviation of the D camera 19 with respect to the drawing stage 5 and the first calibration pattern CR are provided, the drawing of the CCD camera 19 for detecting the amount of positional deviation of the laser beam LB. Even if the fixed position (arrangement position) with respect to the stage 5 is deviated due to environmental changes or the like, the amount of the positional deviation is detected, corrected, and laser drawing is performed. Therefore, the laser drawing accuracy is reduced due to the positional deviation of the CCD camera 19 itself. Can be eliminated, and highly accurate laser drawing can be performed.

The drawing stage 5 of the CCD camera 19
And the position of the printed circuit board S relative to the drawing stage 5 with respect to the second calibration pattern PR of the reference mask RM of the alignment scopes 33, 35, 37, 39 are deviated due to environmental changes. However, since the positional deviations are detected, corrected and laser-drawn, the positional deviations of the CCD camera 19 itself and the alignment scopes 33, 35, 37, 3 are detected.
It is possible to eliminate a decrease in laser drawing accuracy due to the positional deviation of 9 itself, and it is possible to perform more accurate laser drawing.

Further, not only the positional deviation amount of the laser beam LB and the positional deviation amount of the CCD camera 19, but also the positional deviation amount of the substrate S by the alignment scopes 33, 35, 37, 39 and the alignment scopes 33, 35, 3 are detected.
Since the correction of the drawing start position is performed by adding the positional deviation amounts of 7 and 39, it is possible to perform more accurate correction and realize highly accurate laser drawing.

Further, the laser beam LB emitted from the beam scanning mechanism 21 and transmitted through the first calibration pattern CR of the reference mask RM is detected to detect the deviation of the scanning position of the laser beam LB. The first arrangement position detecting means for detecting the amount of displacement of the CCD camera 19 with respect to the drawing stage 5 can be realized with a simple configuration.

Further, since the ND filter 75 dims the laser beam LB from the beam scanning mechanism 21 and makes it incident on the CCD camera 19, it is possible to prevent an excessive input of the light amount to the CCD camera 19.

In addition, the CCD camera 19 is used as a reference mask RM.
When the first calibration pattern CR is captured, the first calibration pattern CR of the reference mask RM is illuminated by the transillumination lamp 77. Therefore, the first calibration pattern CR is suitable for the CCD camera 19. It is imaged.

Further, since the CCD cameras 19 are provided near both ends of the scanning area of the laser beam LB in the main scanning direction, the scanning positions of the laser beam LB near the main scanning start position and near the main scanning end position. Deviations are respectively detected, and deviations of the actual scanning position of the laser beam LB with respect to the main scanning direction of the printed wiring board S can be detected.

Specifically, since the CCD cameras 19 are provided near both ends of the area in the main scanning direction, the following magnification correction and inclination correction can be performed. CC on the drawing start side
The positional shift amount of the laser beam LB detected by the D camera 19 is (ΔXS, ΔYS), and the positional shift amount of the laser beam detected by the CCD camera 19 on the drawing end side is (ΔXE,
ΔYE). The magnification in the X direction is calculated by the following calculation formula (1), and the drawing clock width is corrected by this magnification to correct the magnification. Magnification = ((ΔXE-ΔXS) / distance between both sensors) +1 (1)

The inclination of the main scanning line can also be detected from the difference between ΔYS and ΔYE. Based on this detected tilt, tilting can be corrected by moving the cylindrical lens 98 by the position correcting mechanism 101.

The present invention can be modified as follows.

(1) In the above-described embodiment, the first calibration pattern CR of the reference mask RM provided on the drawing stage 5 is imaged by the CCD camera 19 fixed to the drawing stage 5, so that the CCD camera Although the positional deviation of the CCD camera 19 with respect to the drawing stage 5 is detected, the first calibration pattern CR, such as a position detection sensor that mechanically or optically detects the positional deviation of the CCD camera 19 with respect to the drawing stage 5, is used. Without CCD camera 19
Various sensors capable of detecting the positional deviation with respect to the drawing stage 5 may be adopted.

(2) In the above-described embodiment, the second calibration pattern PR of the reference mask RM is used to detect the positional deviation of the alignment scopes 33, 35, 37, 39. The first calibration pattern CR may be used.

(3) In the above embodiment, different calibration patterns such as the first calibration pattern CR and the second calibration pattern PR are provided, but the first calibration pattern is used as the calibration pattern. You may make it employ | adopt only CR or 2nd calibration pattern PR. CCD camera 19 and each alignment scope 33, 35, 3
The displacement amount of 7, 39 may be detected from the first calibration pattern CR, or the displacement amount of the CCD camera 19 and each of the alignment scopes 33, 35, 37, 39 may be detected from the second calibration pattern PR. It may be detected.

(4) The first calibration pattern CR formed on the reference mask RM is not limited to the double cross shape as shown in FIG. 6, but as shown in FIG. Cross mark line pattern excluding
As shown in (b), the laser beam L having a box shape, etc.
Various types may be adopted in which B does not interfere and the center of the calibration pattern can be calculated by image processing.

(5) In the above-described embodiment, the beam scanning mechanism 21 has a fixed position and the drawing stage 5 moves. However, the present invention is also applicable to a structure in which the beam scanning mechanism 21 moves conversely. It is possible.

(6) In the above-described embodiment, as shown in FIG. 7, the ND filter 75 separate from the reference mask RM is used.
Although the laser beam LB is dimmed by the above and is made incident on the CCD camera 19, as shown in FIG. 12C, the laser beam in the first calibration pattern CR of the reference mask RM as the calibration member is used. The region where LB is incident (the hatched portion) may be used as the dimming member 78 having an appropriate density for dimming the incident laser beam LB. In this case, in order to reduce the laser beam LB incident on the CCD camera 19, the beam scanning mechanism 21 is used.
It is not necessary to separately provide the ND filter 75 shown in FIG. 7 which is located between the beam scanning mechanism 21 and the reference mask RM when the laser beam LB from is captured by the CCD camera 19. The above-mentioned dimming member 78 corresponds to the “dimming member” described in claim 9 of the present invention.

(7) For example, when the printed wiring board S is accurately placed on the drawing stage 5, the positional deviation amount of the alignment scopes 33, 35, 37, 39 and the positional deviation amount of the printed wiring board S are determined. It is not necessary to detect the position shift of the laser beam LB and the CCD camera 1
It suffices to correct the drawing start position based only on the positional deviation of 9.

(8) The number of alignment scopes is not limited to four as in the above embodiment,
The present invention can be applied as long as there is at least one unit.

However, when there is only one alignment scope, the position calibration process relating to alignment is carried out with the printed wiring board placed on the placement table 15.
Then, the alignment scopes are sequentially moved to the reference holes at the four corners, and the positional deviation amount between the center of the visual field and the intersection of the second calibration pattern PR is measured at each position, and at the same time, the center of gravity of the reference hole SR is obtained to obtain the first position. It is necessary to find a relative position error with the intersection of the calibration pattern PR of No. 2.

[0110]

As is apparent from the above description, according to the method invention of claim 1, the arrangement position of the beam position detecting means for detecting the positional deviation amount of the laser beam is deviated due to environmental changes or the like. Also, since the amount of positional deviation is detected and corrected and laser drawing is performed, it is possible to eliminate the decrease in laser drawing accuracy due to the positional deviation of the beam position detection means itself, and it is possible to perform highly accurate laser drawing.

According to the second aspect of the invention, the position of the beam position detecting means for detecting the positional deviation of the laser beam and the position of the object to be drawn for detecting the position of the object to be drawn are detected. Even if the arrangement positions of the means are deviated due to environmental changes and the like, the positional deviation amounts are detected and corrected and laser drawing is performed. Therefore, the positional deviation of the beam position detecting means itself and the object position detecting means itself It is possible to eliminate the deterioration of the laser drawing accuracy caused by the above, and it is possible to perform more accurate laser drawing.

Further, according to the apparatus invention of the third aspect, even if the arrangement position of the beam position detecting means for detecting the positional deviation amount of the laser beam is deviated due to the environmental change or the like, the positional deviation amount is detected. Since the laser drawing is carried out after being corrected, the deterioration of the laser drawing accuracy due to the positional deviation of the beam position detecting means itself can be eliminated, and the laser drawing can be performed with high accuracy.

According to the fourth aspect of the present invention, the position of the beam position detecting means for detecting the amount of positional deviation of the laser beam and the position of the object to be drawn for detecting the position of the object to be drawn are detected. Even if the arrangement positions of the means are deviated due to environmental changes and the like, the positional deviation amounts are detected and corrected and laser drawing is performed. Therefore, the positional deviation of the beam position detecting means itself and the object position detecting means itself It is possible to eliminate the deterioration of the laser drawing accuracy caused by the above, and it is possible to perform more accurate laser drawing.

According to the fifth aspect of the present invention, even if the arrangement position of the beam position detecting means for detecting the positional deviation amount of the laser beam with respect to the holding means is deviated due to environmental changes, etc., the positional deviation amount is caused. Is detected and corrected, and laser drawing is performed, so that it is possible to eliminate the decrease in laser drawing accuracy due to the positional deviation of the beam position detecting means itself, and it is possible to perform highly accurate laser drawing.

Further, according to the apparatus invention of the sixth aspect, the arrangement position of the beam position detecting means for detecting the positional deviation amount of the laser beam with respect to the holding means and the object to be drawn for detecting the position of the object to be drawn. Even if the arrangement position of the body position detecting means with respect to the holding means is deviated due to environmental changes and the like, the amount of positional deviation is detected and corrected and laser drawing is performed. It is possible to eliminate the deterioration of the laser drawing accuracy caused by the positional deviation of the detecting means itself, and it is possible to perform the laser drawing with high accuracy.

According to the apparatus invention of claim 7, the laser beam emitted from the beam scanning means and transmitted through the region of the first calibration pattern of the calibration member is detected, and the position of this laser beam is detected. Since the deviation is detected, the first arrangement position detecting means for detecting the amount of positional deviation of the beam position detecting means with respect to the holding means can be realized with a simple configuration.

Further, according to the apparatus invention of claim 8, since the dimming means dims the laser beam from the beam scanning means and makes it enter the beam position detecting means, the beam position detecting means is connected to the beam position detecting means. It is possible to prevent excessive input of the light amount of.

Further, according to the apparatus invention of the ninth aspect, since at least the region of the calibration member on which the first calibration pattern is formed is a member for dimming the incident laser beam, beam scanning is performed. When a laser beam from the means is imaged by the beam position detecting means, it is positioned between the beam scanning means and the beam position detecting means to dimm the laser beam incident on the beam position detecting means. Need not be provided separately.

According to the apparatus invention of the tenth aspect, when the beam position detecting means images the first calibration pattern of the calibration member, the illuminating means illuminates the calibration member. The calibration pattern No. 1 is preferably imaged by the beam position detecting means.

According to the eleventh aspect of the present invention, the first image pickup means is provided near both ends of the scanning region of the laser beam in the main scanning direction. The positional deviation of the laser beam near the main scanning end position is detected, and the actual positional deviation of the laser beam in the main scanning direction of the object can be detected.

[Brief description of drawings]

FIG. 1 is a perspective view showing a schematic configuration of a laser drawing apparatus according to the present invention.

FIG. 2 is a plan view showing a schematic configuration of the laser drawing apparatus shown in FIG.

FIG. 3 is a side view showing a schematic configuration of the laser drawing apparatus shown in FIG.

FIG. 4 is a partial cross-sectional view of a mounting table.

FIG. 5 is a partial plan view of a mounting table.

6 (a) and 6 (b) are diagrams showing images obtained by capturing a calibration pattern with a CCD camera.

7 is a schematic side view for explaining a peripheral configuration of a CCD camera of the laser drawing apparatus shown in FIG.

FIG. 8 is a block diagram showing a configuration of a control system of the laser drawing apparatus.

FIG. 9 is a CCD of an alignment scope using a reference pattern.
It is a figure which shows the image imaged with the camera.

FIG. 10 is a diagram showing an image obtained by capturing an exposure spot of a laser beam with a CCD camera.

FIG. 11 is a flowchart showing a position calibration process.

12A to 12C are diagrams showing calibration patterns in a modified implementation.

[Explanation of symbols]

3 ... Guide rail (moving means) 5 ... Drawing stage (holding means) 7 ... Servo motor (moving means) 9 ... Feed screw (moving means) 19 ... CCD camera (first imaging means) 21 ... Beam scanning mechanism (beam) Scanning means 31 ... Alignment scope unit (drawing object position detecting means) 33a, 35a, 37a, 39a, ... CCD camera (second imaging means) 50a ... Alignment image processing section (drawing object position detecting means) 50b. Beam shift image processing unit (beam position detection unit) 55 ... System control unit (position correction unit) 57 ... Main scanning control circuit (position correction unit) 61 ... Calibration data storage unit (position correction unit) 74 ... Filter support unit (reduction) Light means) 75 ... ND filter (dimming means) 77 ... Transmitted illumination lamp (illumination means) CR ... First calibration Pattern LB ... Laser beam PR ... Second calibration pattern RM ... Reference mask (calibration member) S ... Printed wiring board (drawing object)

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁷ Identification code FI Theme Coat (reference) H05K 3/00 H05K 3/00 N (72) Inventor Masaaki Yamamoto 4 Horikawa Toujinouchi, Kamigyo-ku, Kyoto Chome Tenjin Kitamachi No. 1 1 Dainippon Screen Mfg. Co., Ltd. In-company F-term (reference) 2H045 BA26 BA32 CA88 CA95 CA98 CA99 2H097 AA03 AB05 CA17 GB04 KA20 KA28 LA09

Claims (11)

[Claims] 1. A beam scanning means for scanning a laser beam along a main scanning direction, and a holding means holding an object to be drawn is relatively moved by a moving means along a sub scanning direction orthogonal to the main scanning direction. In a laser drawing method for drawing a desired pattern on an object to be drawn while moving, a beam position detecting step of detecting a positional deviation amount of a laser beam emitted from the beam scanning means by a beam position detecting means, and the beam position A first arrangement position detecting step of detecting an amount of positional deviation of the arrangement position of the detection means, and detecting the positional deviation amount of the laser beam detected in the beam position detecting step and the first arrangement position detecting step. A laser drawing method, wherein the drawing start position is corrected based on the amount of positional deviation of the beam position detecting means. 2. The laser drawing method according to claim 1, further comprising a drawing object position detecting step of detecting a positional deviation amount of the drawing object held by said holding means by a drawing object position detecting means, A second placement position detecting step of detecting a position shift amount of the placement position of the drawing body position detecting means; and a position shift amount of the laser beam detected in the beam position detecting step and the first placement position. The positional deviation amount of the beam position detecting means detected in the detecting step, the positional deviation amount of the drawing object detected in the drawing object position detecting step, and the positional deviation amount detected in the second arrangement position detecting step. A laser drawing method characterized in that a drawing start position is corrected based on a positional deviation amount of a drawing object position detecting means. 3. A beam scanning means for scanning a laser beam along the main scanning direction, and a holding means holding the object to be drawn is relatively moved by a moving means along a sub scanning direction orthogonal to the main scanning direction. In a laser drawing apparatus that draws a desired pattern on an object to be drawn while moving, a beam position detecting unit that detects a positional deviation amount of a laser beam emitted from the beam scanning unit, and an arrangement position of the beam position detecting unit. Disposition amount detecting means for detecting the positional displacement amount of the laser beam, the positional displacement amount of the laser beam detected by the beam position detecting means, and the beam position detecting means detected by the first disposing position detecting means. A laser drawing apparatus comprising: a position correction unit that corrects the drawing start position based on the positional deviation amount of 4. The laser drawing apparatus according to claim 3, wherein the drawing object position detecting means for detecting a positional deviation amount of the drawing object held by the holding means, and the arrangement of the drawing object position detecting means. The apparatus further comprises: a second arrangement position detecting means for detecting a positional deviation amount of the position, wherein the position correcting means detects the positional deviation amount of the laser beam detected by the beam position detecting means, and the first arrangement position detecting means. Position deviation amount of the beam position detecting means detected by the means, position deviation amount of the object to be drawn detected by the object position detecting means, and the object position detected by the second arrangement position detecting means. A laser drawing apparatus, wherein a drawing start position is corrected based on a positional deviation amount of a drawing object position detecting means. 5. The laser drawing apparatus according to claim 3, wherein the laser beam emitted from the beam scanning unit is fixed to the holding unit at a position where the laser beam can be incident, and the beam scanning is performed. Further comprising a calibration member having a first calibration pattern for calibrating the position of the laser beam emitted from the means, wherein the beam position detection means is incident on the first calibration pattern of the calibration member. A first image pickup means for picking up an image of the laser beam, and based on the image data obtained by the first image pickup means, the amount of positional deviation of the laser beam with respect to the holding means is detected. The detecting means is the first of the calibration members.
The laser drawing apparatus is characterized in that the positional deviation amount of the arrangement position of the beam position detection means with respect to the holding means is detected based on the image data obtained by imaging the calibration pattern of 1. with the first imaging means. .. 6. The laser drawing apparatus according to claim 4, wherein the laser beam emitted from the beam scanning unit is fixed to the holding unit at a position where the laser beam can be incident, and the laser beam is emitted from the beam scanning unit. And a calibration member having a first calibration pattern for calibrating the position of the laser beam and a second calibration pattern for calibrating the arrangement position of the drawing object position detection means with respect to the holding means. The beam position detection means detects a positional deviation amount of the laser beam with respect to the holding means based on image data obtained by imaging the laser beam incident on the first calibration pattern of the calibration member, The first arrangement position detection means is the first calibration member of the calibration member.
Based on the image data obtained by imaging the calibration pattern of the beam position detecting means with the beam position detecting means, the positional deviation amount of the arrangement position of the beam position detecting means with respect to the holding means is detected, A second image pickup means for picking up an image of the object to be drawn held by the means, and detecting a positional deviation amount of the object to be drawn with respect to the holding means based on image data obtained by the second image pickup means, The second arrangement position detection means is the second of the calibration member.
A laser drawing apparatus, which detects the positional deviation amount of the arrangement position of the drawing object position with respect to the holding means, based on image data obtained by imaging the calibration pattern by the second imaging means. 7. The laser drawing apparatus according to claim 5, wherein at least a region of the calibration member in which the first calibration pattern is formed is a laser beam emitted from the beam scanning means. A laser drawing apparatus, which is a transparent member that transmits light, wherein the calibration member is arranged between the beam scanning unit and the first imaging unit. 8. The laser drawing apparatus according to claim 5, wherein when the laser beam from the beam scanning means is imaged by the first imaging means, the beam scanning means and the beam scanning means are used. The laser drawing apparatus further comprising a dimming unit that is disposed between the first image pickup unit and dimms the laser beam incident on the first image pickup unit. 9. The laser drawing apparatus according to claim 5, wherein at least a region of the calibration member on which the first calibration pattern is formed attenuates an incident laser beam. A laser drawing device characterized by being a member. 10. The laser drawing apparatus according to claim 5, wherein when the first calibration pattern is imaged by the first imaging unit, at least the first calibration member has at least the first calibration pattern. The laser drawing apparatus further comprising an illuminating unit that illuminates an area in which the calibration pattern is formed. 11. The laser drawing apparatus according to claim 5, wherein the first imaging unit is located near both ends of a main scanning region of a laser beam scanned by the beam scanning unit. A laser drawing apparatus, which is provided.