JP2591496Y2 - Laser exposure equipment - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser exposure apparatus with a replaceable laser head.

[0002]

2. Description of the Related Art Generally, in a laser exposure apparatus equipped with a laser head using a gas laser, the life of a laser tube is shorter than the life of the apparatus. When replacing the laser head, the optical axis of the laser light output from the newly mounted laser head is aligned with the optical axis of the laser light output from the original laser head. Adjustments need to be made.

[0003]

[Problem to be Solved by the Invention] The optical axis of the laser beam is usually adjusted by observing the return of the laser beam and interference fringes. However, an optical system for guiding the laser beam to an exposure object like a laser exposure apparatus is used. If it is already assembled and fixed, the laser light output from the laser head is returned from the end of the optical system to see the return of the laser light, or the optical path through the optical system and another optical path. It is difficult to irradiate the laser beam with the optical path to the same location to see the interference fringes generated at the irradiated location, and there is a problem that it takes time to adjust the optical axis. Also, temporarily
If the optical axis is adjusted by adjusting the mounting position of the optical system, it is necessary to assemble and adjust individual components of the optical system every time the laser head is replaced, which is troublesome and time-consuming.

The present invention has been made in view of the above-mentioned problem, and has as its object to provide a laser exposure apparatus capable of efficiently adjusting the optical axis of laser light accompanying replacement of a laser head.

[0005]

In order to achieve the above object, the present invention provides a laser head for outputting a laser beam for exposure, a holder for detachably holding the laser head,
In a laser exposure apparatus including a mirror that guides the laser light to the irradiation target side, a target is disposed on an optical path of the laser light transmitted through the mirror without being reflected by the mirror,
An adjustment unit for adjusting the direction of the laser head is provided on the holding unit.

In the present invention, the mirror comprises a light-transmitting base material and a light reflecting film having a predetermined thickness formed on the base material. Further, in the present invention, a plurality of the mirrors are provided, and the target is provided corresponding to at least two of the plurality of mirrors. In addition, the present invention is configured such that the target is configured with a position detector that outputs a signal corresponding to the irradiation position of the laser light, and based on an output signal from the position detector, the position detector of the laser light is transmitted to the position detector. And a display means for displaying the irradiation position of the laser beam calculated by the calculation means.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing a main configuration of a laser exposure apparatus according to an embodiment of the present invention.

In FIG. 1, reference numeral 1 denotes a laser head in which a laser tube of a gas laser is housed. The laser head 1 is detachably held by a holding portion 2 slidable in the direction of arrow A. Two positioning screws 3 for positioning the lower surface 1a (FIG. 2) of the laser head 1 at two locations in the direction of arrow B are screwed into the holding portion 2 from below the holding portion 2, and On the side surface 2a of the holding part 2, the holding part 2 is positioned at two places in the direction of arrow A.
The tips of the two set screws 4 are applied.

FIG. 2 is a partially cutaway side view showing a mounting relationship between the positioning screw 3 and the laser head 1 and the holding portion 2. As shown in FIG. 2, the positioning screw 3 is connected to the laser head via a washer 3a. One side is a large diameter part 3b, and the holding part 2 side is a small diameter part 3c. The tip of the large diameter portion 3b is screwed into a screw hole 1b on the lower surface 1a of the laser head 1,
The small diameter portion 3c is inserted into a through hole 2b formed in the holding portion 2 and having a smaller diameter than the washer 3a and a larger diameter than the small diameter portion 3c. The lower surface 2c of the holding portion 2 is formed with a recess 2d having a substantially circular plane and communicating with the through hole 2b. Nuts 21 and 22 are screwed as double nuts,
It is accommodated in the recess 2d. In this embodiment, the positioning screws 3 and 4 correspond to an adjusting unit.

In FIG. 1, reference numeral 5 denotes an optical system for guiding a laser beam L output from the laser head 1 to a polygon mirror 6. The optical system 5 includes a reflecting mirror 51 for bending the optical path of the laser beam L. , 52, 53, an A / O modulator 54 for modulating the laser light L, a lens system 55 for increasing the diameter of the modulated laser light L, and the like. Reference numeral 7 denotes an fθ lens for scanning the scanning object L (not shown) at a constant speed with the scanning light L11 scanned and deflected by the polygon mirror 6, and 8 irradiates the scanning light L11 vertically to the exposure object (not shown). Reference numeral 9 denotes a condenser mirror for reflecting the scanning light L11 passing through the fθ lens 7 and guiding the scanning light L11 to the condenser lens 8.

The reflecting mirrors 51, 52 and 53 are made of a transparent base material 51a, 52 such as glass or plastic.
a, 53a and light reflecting films 51b, 52b, 53 formed on one surface of the base materials 51a, 52a, 53a by vapor deposition or the like.
b, the thickness of the light reflecting films 51b, 52b, 53b is such that part of the laser light L applied to the light reflecting films 51b, 52b, 53b leaks without being reflected, and The thickness is set to a predetermined value that allows the thickness to pass through 51b, 52b, and 53b. In this embodiment, the reflection mirror 51,
52 and 53 correspond to the mirrors described in the claims.

Further, in FIG. 1, reference numeral 10 denotes a position detector disposed on the optical path of the laser light L transmitted through the reflection mirrors 51, 52 without being reflected by the light reflection films 51b, 52b. The position detector 10 has four output terminals 101 to 104 as shown in FIG.
From the output terminals 10 and 102, a voltage having a value corresponding to the irradiation position Px of the laser beam L in the horizontal direction is output.
From 3,104, a voltage having a value corresponding to the irradiation position Py of the laser beam L in the vertical direction is output.

As shown in FIG. 3, four output terminals 101 to 104 of the position detector 10 are connected to a signal processing circuit (corresponding to an arithmetic circuit) 11, and only one position detector 10 is shown in FIG. However, actually, two position detectors 10 disposed on the back side of the reflection mirrors 51 and 52 are shown.
Output terminals 101 to 104 (8 in total)
(Two output terminals) are connected to the signal processing circuit 11.
Then, in the signal processing circuit 11, 4
V1 output from the output terminals 101 to 104
Through V4 and the horizontal and vertical lengths Sx and Sy of the light receiving surface 105 of each position detector 10 through the light reflecting films 51b and 52b of the reflection mirrors 51 and 52 and each position detector 10 The irradiation positions Px and Py in the horizontal and vertical directions of the laser light L applied to the laser beam L are calculated.

The calculation of the irradiation positions Px and Py of the laser beam L in the horizontal and vertical directions by the signal processing circuit 11 is expressed by the equation P
x = (Sx / 2) × ｛(V1−V2) / (V1 + V
2) 式 and the formula Py = (Sy / 2) × ｛(V3-V4) /
(V3 + V4)}. Further, the calculated irradiation positions Px and Py correspond to the center position P0 of the light receiving surface 105.
From the coordinate value. As shown in FIG. 3, a display device (corresponding to a display means) 12 having a CRT display or the like is connected to the signal processing circuit 11,
On the display device 12, the irradiation positions Px and Py calculated by the signal processing circuit 11 are displayed.

Next, in the laser exposure apparatus of the present embodiment having the above-described configuration, the laser beam L
The case where the optical axis adjustment is performed will be described. First, the laser head 1 is held by the holding unit 2, and the laser light L is output from the laser head 1. Then, the laser light L is reflected by the light reflection film 51b of the reflection mirror 51, and A / A of the optical system 5
The light passes through the O modulator 54, the lens system 55, and the like, is further reflected by the reflection mirrors 52 and 53, and is irradiated on the polygon mirror 6.

At this time, most of the laser light L applied to the reflecting mirrors 51, 52, 53 is reflected by the light reflecting films 51b, 5b.
2b and 53b, but partially reflected by the light reflecting film 51.
b, 52b, 53b, and the reflection mirrors 51, 52,
53 to the back side. For this reason, the light reflecting films 51b, 52
The laser beam L having passed through b is applied to the light receiving surface 105 of the position detector 10 disposed on the back side of the reflection mirrors 51 and 52, and a voltage having a value corresponding to the irradiation position Px or Py is applied to each position detector. The input positions Px and Py of the laser beam L to the position detectors 10 are input to the signal processing circuit 11 from the four output terminals 101 to 104, and are calculated by the signal processing circuit 11 and displayed on the display device 12. You.

By the way, the two position detectors 10 disposed on the back side of the reflection mirrors 51 and 52 are output from the laser heads whose optical axes have been adjusted before the replacement, and the light reflection films 51b and 5 are provided.
The laser beam transmitted through 2b is positioned in advance so as to be applied to the center positions of the two position detectors 10, respectively. Therefore, the operator who replaces the laser head 1 needs two position detectors 1 displayed on the display device 12.
Rotating the positioning screws 3 and 4 while observing the irradiation positions Px and Py of the laser light L to 0, the values of the irradiation positions Px and Py of the laser light L to the two position detectors 10 become “0”. In other words, the positioning of the laser head 1 is adjusted so that the laser beam L transmitted through the reflection mirrors 51 and 52 is applied to the center positions of the light receiving surfaces 105 of the two position detectors 10.

First, when adjusting the positioning of the laser head 1 in the direction of arrow B, the washer 3a is rotated to rotate the two nuts 21 and 22 with respect to the holding portion 2 while the positioning screw 3 is integrated. It is rotated by moving the laser head 1 forward and backward with respect to the positioning screw 3 to adjust the distance between the laser head 1 and the holding unit 2. When adjusting the positioning of the laser head 1 in the direction of arrow A,
The two nuts 21 and 22 are loosened one by one in order to release the fastening of the positioning screw 3 to the holding portion 2, and in this state, the positioning screw 4 is appropriately rotated to rotate the side surface 2 of the holding portion 2.
a, the side surface 2a of the holding portion 2 is applied to the tip of the positioning screw 4, and the two nuts 21 and 22 are again
By tightening.

In the configuration of this embodiment, the laser head 1
Is adjusted in the direction of arrow A by adjusting the difference in diameter between the through hole 2b of the holding part 2 and the small diameter part 3c of the positioning screw 3 or the difference in diameter between the recess 2d of the holding part 2 and the nuts 21 and 22. Can be performed within the range of

As described above, according to the laser exposure apparatus of the present embodiment, the position detector 10 is placed on the optical path of the laser beam L irradiated to the reflecting mirrors 51 and 52 and transmitted through the light reflecting films 51b and 52b. The signal processing circuit 11 determines the irradiation positions Px and Py of the laser beam L to each position detector 10 based on the voltages V1 to V4 output from the four output terminals 101 to 104 of each position detector 10. , And the calculated irradiation positions Px and Py of the laser light L are displayed on the display device 12, and the holding unit 2 holding the laser head 1 is provided with a positioning screw 3 for adjusting the direction of the laser head. , 4 are provided.

Therefore, when the laser head 1 is replaced,
The laser beam L is output from the exchanged laser head 1, and the direction of the laser head 1 is adjusted by the positioning screws 3 and 4 so that the laser beam L is applied to the center position of the light receiving surface 105 of each position detector 10. By adjusting by rotating operation, the optical axis of the laser light L can be easily adjusted to an accurate position, and the optical axis of the laser light L accompanying the replacement of the laser head 1 can be efficiently adjusted.

In this embodiment, the position detectors are arranged on the back side of two of the three reflecting mirrors in total, but the position detectors are arranged on the back side of all the reflecting mirrors. It is good also as a structure provided. Further, in the present embodiment, a position detector is provided on the optical path of the laser light radiated to the reflection mirror and transmitted therethrough, and the irradiation position of the laser light to the position detector is electrically detected. However, instead of the position detector, for example, a target on which an index is written may be provided at a position to be irradiated with the laser light whose optical axis has been adjusted. In this case, the operator who replaces the laser head adjusts the positioning of the laser head so that the irradiation position of the laser light matches the index while observing the irradiation position of the laser light applied to the target. Thus, the optical axis of the laser beam can be easily adjusted to an accurate position.

[0023]

As described above, according to the present invention, in a laser exposure apparatus for guiding an exposure laser beam output from a laser head to an irradiation target side by a mirror, the laser beam passes through the mirror without being reflected by the mirror. The target is disposed on the optical path of the laser light, and the holding unit is provided with an adjustment unit for adjusting the direction of the laser head. Therefore, the adjustment unit is checked while confirming the irradiation position of the laser light applied to the target. By operating and adjusting the direction of the laser head, the optical axis of the laser light can be easily adjusted to an accurate position, and the optical axis of the laser light accompanying the replacement of the laser head can be efficiently adjusted. .

[Brief description of the drawings]

FIG. 1 is a perspective view showing a configuration of a main part of a laser exposure apparatus according to an embodiment of the present invention.

FIG. 2 is a partially cutaway side view showing a mounting relationship between the positioning screw shown in FIG. 1 and a laser head and a holding unit.

FIG. 3 is a block diagram illustrating a schematic configuration of a detection system that detects an irradiation position of a laser beam to the position detector illustrated in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Laser head 2 Holding part 3, 4 Positioning screw (adjustment part) 10 Position detector (target) 11 Signal processing circuit (arithmetic means) 12 Display device (display means) 51, 52 Reflection mirror (mirror) L Laser light Px, Py laser beam irradiation position 51a, 52a Base material 51b, 52b Light reflecting film

Claims (4)

(57) [Scope of request for utility model registration] 1. A laser exposure apparatus comprising: a laser head that outputs laser light for exposure; a holding unit that detachably holds the laser head; and a mirror that guides the laser light to an irradiation target side. A laser exposure apparatus, comprising: a target disposed on an optical path of a laser beam transmitted through the mirror without being reflected by the mirror; and an adjusting unit for adjusting a direction of the laser head in the holding unit. 2. The mirror according to claim 1, wherein the mirror comprises a base material capable of transmitting light and a light reflecting film having a predetermined thickness formed on the base material.
The laser exposure apparatus according to claim 1. 3. The laser exposure apparatus according to claim 1, wherein a plurality of said mirrors are provided, and said target is provided corresponding to at least two of said plurality of mirrors. 4. The target is constituted by a position detector that outputs a signal corresponding to the irradiation position of the laser light, and the target of the laser light to the position detector is output based on an output signal from the position detector. 4. The laser exposure apparatus according to claim 1, further comprising a calculation unit for calculating an irradiation position, and a display unit for displaying the irradiation position of the laser beam calculated by the calculation unit.