JPH0753905B2 - Laser beam lens protection device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a laser beam coating apparatus for coating, for example, mechanical parts or the like with ceramics, metals, etc. (hereinafter referred to as ceramics, etc.), and in particular, evaporation of the window lens thereof. The present invention relates to a lens protection device for protecting objects.

[Conventional technology]

FIG. 3 is a block diagram showing a conventional ceramic coating device using a laser beam. (1) is a laser oscillator, (1a) is a laser beam oscillated from the laser oscillator (1), (2a), (2b), (2c) is the laser beam (1a)
The bend mirror for changing the direction of the beam constitutes a beam transmission optical system for transmitting the laser beam (1a).
(3) is a condenser lens for condensing the laser beam (1a),
(4) is a window lens provided in the vacuum container (5), and the beam transmission optical system (2a) to the condensing lens (3)
A beam introduction optical system is configured to allow the laser beam (1a) transmitted by (2c) to enter the ceramic member (6) in the vacuum container (5). (7) is a ceramic member (6)
A ceramic holder for fixing the substrate, (8) a heater for preheating the ceramic member (6), (9) a substrate which is an object to be coated, (10) a substrate holder for fixing the substrate (9), (11) ) Is a heater for preheating the substrate (9).

The conventional laser ceramic coating device is configured as described above, and transmits the laser beam (1a) oscillated from the laser oscillator (1) by the beam transmission optical systems (2a) to (2c), and the condensing lens (3 ), The light is focused through a window lens (4), introduced into a ceramic member (6) preheated by a heater (8), and irradiated. This laser beam irradiation evaporates the ceramics of the ceramic member (6), and the vaporized substance (61) is arranged to face the ceramic member (6) and is preheated by the heater (11). It is vapor-deposited on and coated.

[Problems to be solved by the invention]

Since the conventional laser-ceramic coating apparatus is configured as described above, the vaporized substance that evaporates from the ceramic member (6) by laser beam irradiation deviates from the direction toward the substrate (9) that is the material to be coated, and the window is often used. It may scatter in the direction of the lens (4) and adhere to the window lens (4). Thus, when the window wound (4) is vapor-deposited, not only the transparency of the laser beam is deteriorated, but also the window lens (4) is deformed by heat absorption, and the laser beam (1a) is transferred to the ceramic member (6). However, there is a problem in that it is not possible to irradiate the surface accurately and the ceramic coating cannot be stably performed.

In order to solve such a problem, it is conceivable to provide a protective cylinder (12) projecting downward from the vacuum container (5) around the window lens (4) as shown in FIG. The beam diameter of (1a) changes depending on the output power, and this output needs to be adjusted every time the material of the ceramic member (6) is changed. Therefore, the inner diameter of the tip opening of the protective cylinder (12) is maximized. It must be larger than the beam diameter. Therefore, the amount of the evaporated substance (61) scattered through the inner surface of the protective cylinder (12) is considerably large, and it is difficult to prevent the evaporated substance (61) from adhering. In addition,
It is conceivable to replace the protective cylinder (12) according to the output of the laser beam (1a), but the replacement work is troublesome and this is not practical either.

The present invention has been made in order to solve the above problems, and an object of the present invention is to obtain a lens protection device for a laser beam, which can significantly reduce the deposition of an evaporated substance on a window lens in a laser coating device. To aim.

[Means for solving problems]

The laser beam lens protection device according to the present invention is provided with a protection tube provided in a vacuum container so as to project from the periphery of a window lens into which a laser beam is incident, and a tip opening portion of the protection tube. And an ultrathin plate that is movably installed. The ultrathin plate is formed of a member that can be pierced by irradiation with the laser beam.

[Action]

In the laser beam lens protection device according to the present invention, when the ceramic coating is started on the ultra-thin plate arranged in the vicinity of the front end opening of the protection cylinder, the ultra-thin plate is first irradiated through the condenser lens and the window lens lens. The laser beam makes a hole having a diameter corresponding to its output. Next, the laser beam that has passed through this hole is applied to the ceramic member or the like, and the evaporated ceramic or the like is vapor-deposited on the substrate to be coated.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. First
The figure is a cross-sectional view of a main part of a laser beam lens protection device. Incidentally, the same or corresponding parts as those of the conventional example shown in FIGS. 3 and 4 are designated by the same reference numerals, and the description thereof will be omitted.

Reference numeral (13) is an ultra-thin plate arranged in the vicinity of the front end opening of the protective cylinder (12), and is made of, for example, strip-shaped stainless steel. (13a) is a hole made in the ultrathin plate (13) by the laser beam (1a), (14) is a storage drum holding the ultrathin plate (13) in a roll, and (15) is the ultrathin plate (13). )
A winding drum for winding the tape as required, (16) a drive motor for rotating the winding drum (15), and (17) a fixture for storing the drum (14) and the drive motor (15). Are fixed to the inner wall of the vacuum container (5). Second
The figure is a view of the portion of the ultrathin plate (13) shown in FIG. 1 from below, and the width of the ultrathin plate (13) is at least larger than the inner diameter of the tip opening of the protective tube (12). It is arranged so as to seal the tip opening.

Next, the operation of the device of the present invention thus configured will be described. When the laser beam (1a) is irradiated to start the ceramic coating, a hole (13a) having a diameter corresponding to the output of the laser beam (1a) is first formed in the ultrathin plate (13), and the ceramic member is opened from this hole (13a). The laser beam (1a) is irradiated to the etc. (6), and the evaporated evaporation material (61) is vapor-deposited on the substrate. At this time, the amount of the evaporated substance (61) scattered from the front end opening of the protective cylinder (12) to the window lens (4) is very small because it is shielded by the ultrathin plate (13), and is scattered to the window lens (4). Can be significantly reduced.

In addition, when the output of the laser beam (1a) is changed, if the output is larger than the previous one, the ultra thin plate (1
The hole (13a) in 3) is re-hole processed (enlarged) to continue the effect of preventing adhesion. On the other hand, when the output of the laser beam (1a) is smaller than that of the previous time, the drive motor (16) rotationally drives the winding drum (15), and the ultrathin plate (1a)
The open part of 3) is wound on the winding drum (15), and the unopened part of the ultra-thin plate (13) is protected by the protective cylinder (1
The laser beam (1a) is extended to the front surface of the tip opening of 2), and the minimum closed hole (13a) corresponding to the output is opened by irradiating the laser beam (1a) again in the initial sealed state.
The material evaporated by is deposited on the substrate. This series of anti-adhesion action is automatically performed according to the processing conditions at that time, and can be performed without opening the vacuum container (5), so that the coating work of ceramics or the like can be efficiently performed.

In the above embodiment, the case where the drive motor (16) is used to drive the winding drum (15) to rotate is described.
Other types of drive devices may be used as long as they can be placed in the vacuum container (5), or the protective cylinder (12)
Various modifications can be implemented, such as arranging the ultrathin plate (13) rotatably close to the.

Further, although the ultra-thin plate (13) has been described as a strip of stainless steel, any shape and material can be used as long as it can be drilled by the laser beam (1a) and can prevent the vaporized substance (61) from scattering. It may be one.

〔The invention's effect〕

As described above, according to the present invention, the ultrathin plate is arranged in the vicinity of the tip opening of the protective cylinder, and when coating the ceramics or the like with the laser beam, a hole having a diameter corresponding to the output of the laser beam is opened. As a result, it is possible to significantly reduce the adherence of evaporative substances to the window lens and respond to changes in the laser beam output and changes in processing conditions. Can be done.

[Brief description of drawings]

FIG. 1 is a sectional view showing an essential part of an embodiment of the present invention, and FIG.
FIG. 3 is a bottom view of the main part, FIG. 3 is a cross-sectional view showing the structure of a conventional laser ceramic coating apparatus, and FIG. 4 is a cross-sectional view of the main part of another conventional example. In the figure, (1a) is a laser beam, (3) is a condenser lens, (4) is a window lens, (6) is a ceramic member, (12) is a protective cylinder, (13) is an extremely thin plate, and (14). Is a storage drum, (15) is a winding drum, and (16) is a drive motor. The same reference numerals in the drawings indicate the same or corresponding parts.

Claims (3)

[Claims] 1. A device for irradiating ceramics or the like with a laser beam in a vacuum container to evaporate the ceramics or the like and deposit the ceramics or the like on a surface of a substrate to be coated, wherein the laser beam provided in the vacuum container is incident. The protection tube is provided so as to project from the periphery of the window lens into the vacuum container, and an ultrathin plate movably installed near the tip opening of the protection tube. The ultrathin plate is irradiated with the laser beam. A protection device for a laser beam lens, characterized by being formed of a member capable of being pierced by. 2. The laser beam lens protection device according to claim 1, wherein the ultrathin plate is formed in a band shape so as to be movable by the winding drum. 3. The laser beam lens protection device according to claim 1, wherein the ultrathin plate is formed in a disk shape so as to be rotatable.