JPH04294889A - Mask type laser making device - Google Patents

Abstract

PURPOSE:To make the handling easy by approaching and assembling two pieces of thin cylindrical convex lenses, and working with the primary laser light emitted with rotating both lenses relatively. CONSTITUTION:The composition is made so that the primary optical laser 22 whose sectional shape and size is changed continuously by rotating both convex lenses relatively is emitted from the assembled lens composed of two pieces of thin cylindrical convex lenses 18, 19 positioned nearby, the working is executed by irradiating the primary laser light 22 to the mask 13. The handling can be made easy, and also the life of lamp for exciting the light on the laser oscillator can be prolonged.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention projects a primary laser beam having a thickness that completely covers the mask pattern onto a mask on which a predetermined mask pattern such as characters and figures is formed, and the primary laser beam passes through the mask. A mask-type laser engraving device that uses a secondary laser beam to engrave an engraving pattern corresponding to the mask pattern on a workpiece at once, which is required depending on the shape and size of the mask. The present invention relates to a device that is easy to handle and can extend the life of a light excitation lamp in a laser oscillator.

0002

[Prior Art] In the above-mentioned mask type laser engraving device, the thickness of the primary laser beam that irradiates the mask is greater than or equal to the thickness that covers the whole mask at once, and It is necessary that the energy density Ed is equal to or higher than the minimum value Eda required for marking, and the total energy Et of the primary laser beam is equal to the voltage applied to the optical excitation lamp in the laser oscillator as the light source of this laser beam. It is controlled by V, but if V becomes high, the life of the lamp will be significantly shortened, so in the above-mentioned mask type laser engraving device, it is necessary to lower the voltage V as much as possible in order to extend the life of the lamp. Therefore, conventionally, when the mask is a square M1 with a side length L as shown in FIG. If a circle C circumscribes a square M1 and the mask is a rectangle M2 with a long side 2L and a short side (1/2)L shown in FIG. The ellipse E circumscribes a rectangle M2 with a minor axis (1/2) AL, and the ellipse E has a chord length in the short side direction of the rectangle M2 in a circle with a diameter 2AL equal to 1/4. This is the figure obtained by shortening it to . Then,
In order to obtain a primary laser beam with the cross section shown above,
Conventionally, a mask type laser engraving device is configured as shown in FIG. Hereinafter, a mask having a square M1 will be referred to as a mask M1, and a mask having a rectangle M2 will be referred to as a mask M.
There is a case of 2.

Now, in FIG. 7, 1 has a built-in laser oscillator 3 equipped with the above-mentioned optical excitation lamp 2, and performs necessary optical processing on the cross-sectional shape of the original laser beam emitted by this oscillator 3. A beam light generator 4 is configured to emit a beam 1a as a laser beam having a circular cross section with a diameter D1 equal to AL, and 4 is arranged so that each optical axis thereof coincides with the optical axis 1a1 of the beam 1a. The lens 5 consists of a spherical concave lens 5 and a spherical convex lens 6.
An expander 8 converts the beam light 1a incident therein into a laser beam 7 as a parallel beam having a circular cross section with a diameter D2 equal to 2AL and emits it from a lens 6, each optical axis 8 being the optical axis 4a of the expander 4. It is made up of a cylindrical convex lens 9 and a cylindrical concave lens 10 arranged so as to match the cylindrical convex lens 9 and the cylindrical concave lens 10, and converts the laser beam 7 incident on the lens 9 into a primary laser beam 11 as a parallel light beam having a cross-sectional shape of an ellipse E shown in FIG. A reducer 12 is configured to emit light from a lens 10, and 12 is provided with a mask 13 into which the primary laser beam 11 is incident, and a workpiece 15 is irradiated with a secondary laser beam 14 as the laser beam 11 that has passed through the mask 13. This is the laser light emitting section. Then, 16 is a mask type laser engraving device consisting of the above-mentioned beam light generator 1, expander 4, reducer 8 and laser light emitting section 12,
In this device 16, each part is configured as described above, so by setting the applied voltage V of the lamp 2 so that the energy density of the primary laser beam 11 is equal to or higher than the above-mentioned Eda, the mask 13 is It is clear that the marking pattern corresponding to the mask pattern 13a can be stamped on the workpiece 15 at one time.

Since the laser engraving device 16 is constructed as described above, the mask M as the mask 13 can be used as is.
2, and since the energy density of the laser beam 1a and the energy density of the primary laser beam 11 are almost equal, by removing the expander 4 and reducer 8 from this device 16, the marking can be performed immediately. It is clear that marking can be performed using the mask M1 as the mask 13, and for this reason, the marking device 16 has the expander 4 and the reducer 8 detachably configured, and as a result, the marking device 16 Mask M1,
The device can immediately handle markings using either M2.

[0005]

[Problems to be Solved by the Invention] Since the marking device 16 is constructed as described above, it is possible to use the mask M as the mask 13.
It can be used for engraving using either 1 or M2, but
In this case, depending on the size of the mask 13, the expander 4
Also, since it is necessary to attach and remove the reducer 8 and to adjust the optical axis, there is a problem that handling is troublesome. Conventionally, in order to solve this problem, regardless of whether the mask 13 is M1 or M2, the reducer 8 is removed from the device 16 and the mask 13 is directly irradiated with the laser beam 7. However, in this case, in order to make the total energy of beam 7 four times that of when reducer 8 is installed, lamp 2
Since the applied voltage V must be higher than when the reducer 8 is attached, there is a problem in that the life of the lamp 2 is significantly shortened in the marking device in which the reducer 8 is removed.

An object of the present invention is to eliminate the need for attaching and detaching the expander 4 and reducer 8 and adjusting the optical axis depending on the size of the mask 13, thereby improving the performance of a mask-type laser engraving device. In addition to facilitating handling, the total energy of the beam 7 does not have to be quadrupled compared to when the reducer 8 is attached, and engraving can be performed on both masks M1 and M2 without attaching or detaching the reducer 8 for optical excitation. The purpose of this invention is to extend the life of the lamp 2.

[0007]

[Means for Solving the Problems] In order to achieve the above object, according to the present invention,

1) Consisting of two thin cylindrical convex lenses arranged close to each other so that their optical axes coincide, and the biconvex lens is formed to be relatively rotatable around the lens optical axis. and a laser beam generator that generates a laser beam having a circular cross section with a predetermined diameter and makes the laser beam enter the combined lens so that the beam optical axis of the laser beam coincides with the optical axis of the lens. The vessel and
A laser beam emitting unit is provided with a mask into which the primary laser beam as the laser beam that has passed through the combination lens is incident, and that irradiates the workpiece with the secondary laser beam as the primary laser beam that has passed through the mask. , a mask-type laser engraving device is configured to inscribe an engraving pattern corresponding to a mask pattern provided on the mask on the workpiece at once by irradiating the workpiece with the secondary laser beam;

[0009]2
) In the marking device described in item 1) above, the mask type laser marking device is configured such that the two thin cylindrical convex lenses forming the combined lens both have the same focal length, and

3) In the marking device described in item 2) above, the focal length of this combination lens is determined from the combination lens in which each attitude of the biconvex lens is set so that the optical axis plane of each of the biconvex lenses is in the same plane. A mask-type laser marking device is constructed by arranging a mask at a position on the optical axis of the lens, which is approximately 3/4 of the distance from the lens.

[0011]

[Operation] With the above configuration, the cross section of the primary laser beam becomes an ellipse when each optical axis plane of the biconvex lens is in the same plane due to relative rotation around the optical axis of the biconvex lens. When the optical axis planes of the biconvex lenses are made perpendicular to each other by the above relative rotation, the cross section of the primary laser beam becomes circular, and the cross section of the primary laser beam becomes circular according to the change in the intersection angle of both optical axis planes. The cross section is continuously deformed between the ellipse and circular shape, and the focal length of the combined lens changes depending on the focal length of each convex lens, so both optical axis planes change depending on the shape and size of the mask. By appropriately setting the intersection angle, the position of the mask, and the focal length of each convex lens, the cross-sectional shape of the primary laser beam at the position of the mask can be made into a shape that is exactly circumscribed to the mask or slightly larger than the mask. Therefore, even if the shapes and sizes of the masks are different, the above-mentioned optical components such as attaching and detaching the expander 4 and reducer 8 and adjusting their optical axes, which are necessary in the conventional marking device 16, can be easily adjusted. Immediate marking can be performed without having to perform attachment/detachment operations, and the cross-sectional area of the primary laser beam does not have to be as large as four times the required area, which is the case when marking is performed by removing the reducer 8 from the conventional device 16. The marking device is easy to handle and can be used for masks of different shapes and sizes without the need to attach or detach optical parts. A laser marking device with a long service life can be obtained.

0012

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a block diagram of an embodiment of the present invention. In this figure, the same components as in FIG. 7 are given the same reference numerals as in FIG. In FIG. 1, reference numeral 17 consists of two thin cylindrical convex lenses 18 and 19 having the same focal length Fc and arranged close to each other so that their optical axes 18a and 19a coincide. A combination lens 20 is formed to be relatively rotatable around optical axes 18a and 19a by means not shown, and 20 is composed of a beam light generator 1 and an expander 4, and has a predetermined diameter D2= A laser beam that generates a laser beam 7 having a circular cross section of 2AL and makes the beam 7 incident on the lens 18 of the combined lens 17 so that the beam optical axis 7a of the beam 7 coincides with the lens optical axes 18a and 19a. The generator 21 includes a mask 13 into which the primary laser beam 22 as the laser beam 7 that has passed through the lens 17 is incident, and a reflecting mirror 24 that reflects the secondary laser beam 23 as the laser beam 22 that has passed through the mask 13. , and an imaging lens 25 that focuses the laser beam 23 reflected by the mirror 24 and forms an image of the mask pattern 13a on the workpiece 15, and 26 is the combination lens 1 described above.
7, a laser beam generator 20, and a laser beam emitting section 21
This is a mask type laser engraving device equipped with. Then, in the marking device 26, the optical axis surface 18b of the lens 18 is
This lens 1 is obtained from the combination lens 17 in the state shown in FIG.
The lens optical axis 18 is located at a distance of 3/4 of the focal length Fa of 7.
A mask 13 is placed at position B above a and 19a. In the marking device 26, the optical axes 18a and 19a are in the same state, so hereinafter both the optical axes 18a and 19a may be collectively referred to as the optical axis 17a of the lens 17.

Since the marking device 26 is constructed as described above, when the respective postures of both lenses 18 and 19 are set so that the optical axis planes 18b and 19b are in the same plane as shown in FIG. The lens 17 becomes equivalent to the cylindrical convex lens having the focal length Fa shown in FIG.
Since Fa≈(1/2)·Fc, the cross section of the primary laser beam 22 at position B on the optical axis 17a is equal to the ellipse E shown in FIG. Since the device 26 is configured as described above, the state shown in FIG. The time lens 17 is equivalent to a spherical lens having a focal length Fb shown in FIG.
/8). Then, this circle is larger than the circle with diameter AL, and has a diameter of 2A.
It is clear that the circle is smaller than the circle L.

Therefore, according to the marking device 26, the lens 17
If the applied voltage V of the lamp 2 is set so that the energy density Ed of the laser beam 22 at the position B becomes at least the above-mentioned minimum level Eda when the state shown in FIG. Mask M on the engraving and position B
2 can be performed by relatively rotating the lenses 18 and 19 to bring the lens 17 into the state shown in FIG. 3 or into the state shown in FIG. 2. In this case, the conventional marking device 1
The marking device 26 is easier to handle than the marking device 16 because there is no need to perform attachment/detachment operations for optical components such as attachment/detachment of the expander 4 and reducer 8 performed in step 6, or to adjust the optical axis of these optical components. This means that it is a suitable device. Then, in the marking device 26, the lens 17
The laser beam 22 at position B when is in the state shown in Figure 3.
The cross-sectional area S1 of is (π/4)・{2AL・(5/8)}2
, and this S1 is equal to the minimum area necessary to cover the mask M1. The cross-sectional area of the beam 1a is S2=
(π/4)・(AL)2 Since it is about 1.56 times, the applied voltage V of the lamp 2 can be made much lower than in the case of a conventional marking device in which the reducer 8 is removed from the marking device 16. Therefore, the marking device 26 is
Similar to the conventional device 16 in which the reducer 8 is removed, the masks M1 and M2 can be removed without attaching or detaching optical components.
Although it is a marking device that can be used for both, it is a device that can extend the life of the lamp 2.

In the above embodiment, it is assumed that the focal length F18 of the lens 18 and the focal length F19 of the lens 19 are equal and the mask 13 is placed at the position B.
In the present invention, it is clear that F18 and F19 may be different, and that the mask 13 may be placed at a position other than position B on the optical axis 17a. Then, in the case of the device of the present invention, the mask 13 is the mask M1, M2.
It is also clear that it may have other shapes and sizes.

[0016]

[Effects of the Invention] As mentioned above, in the present invention,

[
1) A combination consisting of two thin cylindrical convex lenses arranged closely so that their respective optical axes coincide, and a biconvex lens formed to be relatively rotatable around the lens optical axis. A laser beam generator that generates a laser beam having a circular cross section with a predetermined diameter and makes the laser beam enter the combination lens so that the beam optical axis of the laser beam coincides with the optical axis of the lens, and the combination lens. A laser beam emitting unit is provided with a mask into which the primary laser beam transmitted as the laser beam is incident, and a laser beam emitting section that irradiates the workpiece with the secondary laser beam as the primary laser beam that has passed through the mask. The mask-type laser engraving device is configured to engrave an engraving pattern corresponding to the mask pattern provided on the mask on the workpiece at once by irradiating the mask, and

2) In the marking device described in item 1) above, the mask type laser marking device is configured such that the two thin cylindrical convex lenses forming the combined lens both have the same focal length, and

3) In the marking device described in item 2) above, the focal length of this combination lens is determined from a combination lens in which each posture of the biconvex lens is set so that the optical axis plane of each of the biconvex lenses is in the same plane. A mask-type laser engraving device was constructed by arranging a mask at a position on the optical axis of the lens that was approximately 3/4 the distance from the lens.

Therefore, with the above configuration, the cross section of the primary laser beam is When the optical axis planes of the biconvex lenses are made perpendicular to each other by the relative rotation described above, the cross section of the primary laser beam becomes circular, and the cross section of the primary laser beam changes depending on the change in the intersection angle of both optical axis planes. The cross section of the light is continuously deformed between the ellipse and the circular shape, and the focal length of the combined lens changes depending on the focal length of each convex lens, so the shape and size of the two lights change depending on the shape and size of the mask. By appropriately setting the intersection angle of the axial planes, the position of the mask, and the focal length of each convex lens, the cross-sectional shape of the primary laser beam at the position of the mask can be made into a shape that just circumscribes the mask or is slightly larger than the mask. Therefore, even if the shapes and sizes of the masks are different, optical components such as attaching and detaching the expander 4 and reducer 8 and adjusting their optical axes, which are necessary in the conventional marking device 16 described above, can be maintained. The cross-sectional area of the primary laser beam can be made as large as four times the area required, unlike the case of conventional marking performed by removing the reducer 8 from the device 16. Therefore, the present invention is easy to handle and can be used to attach and detach optical components of different shapes and sizes.
The present invention has the effect of providing a laser engraving device that can be used for masks of various sizes and can extend the life of the optical excitation lamp in the laser beam generator.

[Brief explanation of drawings]

[Fig. 1] Configuration diagram of one embodiment of the present invention

[Fig. 2] An explanatory diagram of one aspect of the combination lens shown in Fig. 1.

FIG. 3 is an explanatory diagram of a different aspect from the aspect shown in FIG. 2 of the combined lens shown in FIG. 1;

[Fig. 4] Functional explanatory diagram of the combination lens of the embodiment shown in Fig. 2

[Fig. 5] Functional explanatory diagram of the combination lens shown in Fig. 3

[Figure 6] Explanatory diagram of the cross section of the primary laser beam in a conventional laser engraving device

[Figure 7] Configuration diagram of a conventional laser engraving device

[Explanation of symbols]

7 Laser beam 7a Beam optical axis 13 Mask 13a Mask pattern 15 Work 17 Combination lens 18 Thin cylindrical convex lens 18a Lens optical axis 18b Optical axis surface 19 Thin cylindrical convex lens 19a
Lens optical axis 19b Optical axis plane 20 Laser beam generator 21 Laser light emitting section 22 Primary laser beam 23 Secondary laser beam 26 Laser engraving device

Claims (3)

[Claims] Claims: 1. Consisting of two thin cylindrical convex lenses arranged closely so that their optical axes coincide, the biconvex lens being formed to be relatively rotatable around the lens optical axis. combination lens,
a laser beam generator that generates a laser beam having a circular cross section with a predetermined diameter and makes the laser beam enter the combination lens such that the beam optical axis of the laser beam coincides with the optical axis of the lens; and the combination. a laser beam emitting section that is provided with a mask into which the primary laser beam as the laser beam that has passed through the lens is incident, and that irradiates the workpiece with the secondary laser beam as the primary laser beam that has passed through the mask; A mask-type laser engraving device characterized in that a marking pattern corresponding to a mask pattern provided on the mask is imprinted on the workpiece at once by irradiating the workpiece with a secondary laser beam. 2. The mask type laser marking device according to claim 1, wherein the two thin cylindrical convex lenses forming the combined lens both have the same focal length. 3. In the marking device according to claim 2, the focal length of the combination lens is determined from a combination lens in which each attitude of the biconvex lens is set so that the optical axis plane of each of the biconvex lenses is in the same plane. A mask-type laser engraving device characterized in that a mask is placed at a position on the optical axis of a lens at a distance of approximately 3/4.