JP2836273B2 - Mask type laser engraving device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of projecting a primary laser beam having a thickness covering all the mask pattern on a mask on which a predetermined mask pattern such as a character or a figure is formed, and passing the primary laser beam through the mask. A mask type laser engraving device that engraves an engraving pattern corresponding to the mask pattern with a secondary laser beam on a work as an engraved object at a time, particularly, is required depending on the shape and size of the mask. The present invention relates to a device that can be easily handled and can prolong the life of a light excitation lamp in a laser oscillator.

[0002]

2. Description of the Related Art In the above-described mask type laser engraving apparatus, the thickness of a primary laser beam for irradiating a mask is larger than the thickness covering all of the mask at one time, and the primary laser light per unit sectional area. It is necessary that the energy density Ed as energy is not less than the minimum limit Eda required for marking, and the total energy Et of the primary laser light is a voltage applied to a light excitation lamp in a laser oscillator as a light source of the laser light. Since the lamp life is greatly shortened when V is increased, it is necessary to make the voltage V as low as possible in the above-mentioned mask type laser engraving apparatus in order to extend the life of the lamp. Therefore, conventionally, when the mask is a square M1 having a side length L as shown in FIG. Is a circle C circumscribing the square M1 of the diameter AL shown in FIG. 6 with A being the square root of 2, and the mask is a rectangle M2 having a long side 2L and a short side (1/2) L shown in FIG. In some cases, the cross section of the primary laser beam is formed into an ellipse E circumscribing a rectangle M2 having a major axis 2AL and a minor axis (1/2) AL shown in FIG. It is a figure obtained by reducing the length of the chord in the short side direction of the rectangle M2 in the circle to １ ／. And then
In order to obtain a primary laser beam with a cross section as described above,
Conventionally, a mask type laser engraving device is configured as shown in FIG. Hereinafter, a mask having a square M1 is referred to as a mask M1, and a mask having a rectangle M2 is referred to as a mask M1.
Sometimes it is 2.

In FIG. 7, reference numeral 1 denotes a laser oscillator 3 provided with the above-mentioned light pumping lamp 2 and performs necessary optical processing on the cross-sectional shape of the original laser light emitted from the oscillator 3. The beam light generator 4 which emits a beam light 1a as a laser beam having a circular cross section having a diameter D1 equal to AL is disposed such that each optical axis coincides with the optical axis 1a1 of the beam light 1a. An expander comprising a spherical concave lens 5 and a spherical convex lens 6, wherein the light beam 1 a incident on the lens 5 is converted into a laser beam 7 as a parallel light beam having a circular cross section having a diameter D2 equal to 2AL and emitted from the lens 6. Reference numeral 8 denotes a cylindrical convex lens 9 and a cylindrical concave lens 10 which are arranged such that their optical axes coincide with the optical axis 4a of the expander 4. Rannahli, lens and the laser beam 7 incident on the lens 9 to the primary laser beam 11 as a parallel beam having a cross-sectional shape of an ellipse E shown in FIG. 6 10
A reducer 12 is provided with a mask 13 on which a primary laser beam 11 is incident, and irradiates a workpiece 15 with a secondary laser beam 14 as the laser beam 11 passing through the mask 13. This is a laser light emitting unit. Reference numeral 16 denotes a mask type laser engraving device including the above-described beam light generator 1, expander 4, reducer 8, and laser light emitting unit 12. In this device 16, each unit is configured as described above. The voltage V applied to the lamp 2 is adjusted so that the energy density of the primary laser light 11 is equal to or higher than the above-mentioned Eda.
Is set, the engraving pattern corresponding to the mask pattern 13a provided on the mask 13 is
It is evident that they can be engraved at once.

Since the laser marking device 16 is constructed as described above, the mask M as the mask 13 is used as it is.
2 and the energy density of the laser beam 1a is substantially equal to the energy density of the primary laser beam 11, so that by removing the expander 4 and the reducer 8 from the device 16, It is clear that engraving using the mask M1 as the mask 13 can be performed. For this reason, in the engraving device 16, the expander 4 and the reducer 8 are each configured to be detachable, and as a result, the engraving device 16 Mask M1,
It is a device that can immediately respond to the marking using any of M2.

[0005]

Since the marking device 16 is constructed as described above, the mask M as the mask 13 is used.
It can be used for engraving using either M1 or M2.
In this case, depending on the size of the mask 13, the expander 4
In addition, since it is necessary to attach and detach the reducer 8 and adjust the optical axis, there is a problem that the handling is troublesome. Therefore, 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, the lamp 2 is used to increase the total energy of the beam 7 to four times that when the reducer 8 is attached.
Must be higher than when the reducer 8 is attached, the marking device from which the reducer 8 is removed has a problem that the life of the lamp 2 is greatly shortened.

An object of the present invention is to eliminate the need for mounting, removing, and adjusting the optical axis of the expander 4 and the reducer 8 according to the size of the mask 13 so that the mask type laser engraving device can be used. The energy of the beam 7 is reduced and the energy of the beam 7 is reduced.
Masks M1 and M2 even if they are not quadrupled when attaching
The purpose of the present invention is to extend the life of the light excitation lamp 2 by making it possible to perform engraving without attaching and detaching the reducer 8 for both.

[0007]

In order to achieve the above object, according to the present invention,

1) Two thin cylindrical convex lenses arranged close to each other so that the optical axes of the lenses coincide with each other, and the biconvex lens is formed so as to be relatively rotatable around the optical axis of the lens. And a laser beam generating a laser beam having a circular cross section of a predetermined diameter and causing the laser beam to enter the combination lens such that the beam optical axis of the laser beam coincides with the lens optical axis. Vessels,
A mask, on which the primary laser light transmitted through the combination lens is made incident, is provided, and a laser light emitting unit that irradiates the work with the secondary laser light that has passed through the mask is provided, according to the shape and size of the mask. A mask type laser engraving apparatus for engraving the engraved pattern corresponding to the mask pattern provided on the mask at once by appropriately setting the intersection angle of both optical axis surfaces, the position of the mask, and the focal length of each convex lens on the work. Constitutes

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

3) In the marking device according to the above item 2), the focal length of the biconvex lens is changed from the combination lens in which each posture of the biconvex lens is set such that the respective optical axis surfaces are in the same plane. Almost 3/4 of
A mask type laser engraving apparatus is constructed by disposing a mask at a position on the lens optical axis at a distance of.

[0011]

[Work] With the above configuration, when the optical axis surfaces of the biconvex lens are in the same plane by relative rotation of the biconvex lens around the optical axis, the cross section of the primary laser beam becomes elliptical. When the respective optical axis surfaces of the biconvex lens are made perpendicular to each other by the relative rotation, the cross section of the primary laser beam becomes circular, and the primary laser light beam changes according to the change of the intersection angle between the two optical axis surfaces. Since the cross section is continuously deformed between the ellipse and the circle, and the focal length of the combination lens changes according to the focal length of each convex lens, the two optical axis planes are changed according to the shape and size of the mask. The cross-sectional shape of the primary laser beam at the position of the mask is circumscribed to the mask or a figure slightly larger than the mask by appropriately setting the intersection angle of the mask, the position of the mask, and the focal length of each convex lens. Therefore, even if the shape and size of the mask are different, the expander 4 and the reducer 8 required for the above-described conventional engraving device 16 are used.
Imprinting can be performed immediately without attaching / detaching optical components such as attaching / detaching the optical axis and adjusting the optical axis. Also, the primary laser as in the case of the engraving performed by removing the reducer 8 from the conventional device 16 is used. Since the cross-sectional area of light does not need to be as large as four times the required area, masks of different shapes and sizes are easy to handle and do not need to attach or detach optical components. A laser engraving device that can be used but can extend the life of the light excitation lamp in the laser beam generator while being a usable engraving device can be obtained.

[0012]

FIG. 1 is a block diagram of an embodiment of the present invention, in which the same components as those in FIG. 7 are denoted by the same reference numerals as in FIG. In FIG. 1, reference numeral 17 denotes two thin cylindrical convex lenses 18 and 19 having the same focal length Fc and arranged close to each other so that their lens optical axes 18a and 19a coincide with each other. Is a combination lens which is relatively rotatably formed around the optical axes 18a and 19a by means not shown, and 20 is composed of the beam light generator 1 and the expander 4, and has a diameter D2 = a predetermined diameter. A laser beam that generates a laser beam 7 having a circular cross section of 2AL, and causes the beam 7 to be incident on the lens 18 of the combination lens 17 so that the beam optical axis 7a of the beam 7 coincides with the lens optical axes 18a and 19a. A generator 21 is a mask 13 on which a primary laser beam 22 as a laser beam 7 transmitted through a lens 17 is incident. A reflecting mirror 24 for reflecting a secondary laser beam 23 as a laser beam 22 passing through the mask 13; and a laser beam 23 reflected by the mirror 24 is condensed to form an image of the mask pattern 13a on the work 15. A laser beam emitting portion comprising an imaging lens 25 to be formed;
7, laser beam generator 20 and laser light emitting section 21
And a mask type laser engraving device comprising: Then, in the marking device 26, the optical axis surface 18 of the lens 18
The focal length of the lens 17 from the combination lens 17 in the state of FIG. 2 in which the respective postures of the two lenses 18 and 19 are set so that b and the optical axis surface 19b (shown in FIG. Lens optical axis 1 at a distance of 3/4 of Fa
The mask 13 is arranged at a position B on 8a and 19a. Since the optical axes 18a and 19a coincide with each other in the marking device 26, the two optical axes 18a and 19a may be hereinafter collectively referred to as the optical axis 17a of the lens 17.

Since the marking device 26 is constructed as described above, the position of the two lenses 18 and 19 in the state of FIG. 2 is set so that the optical axis surfaces 18b and 19b are in the same plane. The lens 17 is equivalent to the cylindrical convex lens having the focal length Fa shown in FIG. 4, and in this case, the lens 17 has the two lenses 18 and 19 having the same focal length Fc.
≒ (１ ／) · Fc, and the primary laser light 22 at the position B on the optical axis 17a is
Is equal to the ellipse E shown in FIG. And then
Further, since the device 26 is configured as described above, the lens 17 in the state shown in FIG. 3 in which the respective postures of the lenses 18 and 19 are set so that the optical axis surfaces 18b and 19b are perpendicular to each other, This is equivalent to a spherical lens having the focal length Fb shown in FIG. 5, in which case Fb ≒ Fc and the optical axis 17a
The cross section of the laser beam 22 at the upper position B is 2AL ·
A circle having a diameter equal to (5/8). Thus, it is clear that this circle is larger than the circle of diameter AL and smaller than the circle of diameter 2AL.

Therefore, according to the marking device 26, the lens 17
When the voltage V applied to the lamp 2 is set so that the energy density Ed of the laser beam 22 at the position B in the state of FIG. 3 is at least the minimum limit Eda, the mask M1 is placed at the position B. Engraving and mask M at position B
2 can be performed by rotating the lenses 18 and 19 relative to each other to bring the lens 17 to the state shown in FIG. 3 or to the state shown in FIG.
Since it is not necessary to perform the attaching and detaching operations of the optical components such as the attaching and detaching of the expander 4 and the reducer 8 and the optical axis adjustment of the optical components, the marking device 26 is easier to handle than the marking device 16. It means that it is a simple device. Then, in the marking device 26, the lens 17
The laser beam 22 at the position B when
Is the cross-sectional area S1 of (π / 4) · {2AL · (5/8)} ²
S1 is equal to the minimum area required to cover the mask M1, and the cross-sectional area S2 =
(Π / 4) · (AL) ² is about 1.56 times, so
The applied voltage V of the lamp 2 can be made much lower than in the case of the engraving device in which the reducer 8 is removed from the conventional engraving device 16, so that the engraving device 26 removes the reducer 8 from the conventional device 16. It is a marking device that can be used for both the masks M1 and M2 without attaching and detaching optical components, as in the device described above, but can extend the life of the lamp 2.

In the above embodiment, the focal length F18 of the lens 18 and the focal length F19 of the lens 19 are equal and the mask 13 is located at the position B.
In the present invention, it is apparent that F18 and F19 may be different, and that the mask 13 may be arranged at a position other than the position B on the optical axis 17a. Then, in the case of the apparatus of the present invention, the mask 13 is formed by the masks M1 and M2.
It is also clear that other shapes and sizes may be used.

[0016]

As described above, in the present invention,

1) Consisting of two thin cylindrical convex lenses arranged close to each other such that the optical axes of the lenses coincide with each other, and the biconvex lens is formed so as to be relatively rotatable around the optical axis of the lens. A combination lens,
A laser beam generator for generating a laser beam having a circular cross section of a predetermined diameter and for causing the laser beam to enter the combination lens such that the beam optical axis of the laser beam coincides with the lens optical axis, and a laser transmitted through the combination lens A mask on which the primary laser light as a beam is incident is provided, and a laser light emitting unit for irradiating the work with the secondary laser light as the primary laser light passing through the mask is provided. Configure a mask type laser engraving device to engrave the engraving pattern corresponding to the mask pattern provided on the mask at once on the work,

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

3) In the marking device described in the above item 2), the focal length of the biconvex lens is changed from the combination lens in which each posture of the biconvex lens is set so that the respective optical axis surfaces of the biconvex lens are in the same plane. A mask type laser engraving apparatus was constructed by disposing a mask at a position on the optical axis of the lens which was located at a distance of about ／.

For this reason, with the above configuration, when the respective optical axis surfaces of the biconvex lens are in the same plane by the relative rotation around the lens optical axis of the biconvex lens, the cross section of the primary laser beam becomes When the optical axis surfaces of the biconvex lens are made perpendicular to each other by the relative rotation described above, the cross section of the primary laser beam becomes circular, and the primary laser beam changes according to the change in the intersection angle of both optical axis surfaces. The cross section of the light is continuously deformed between the ellipse and the circle, and the focal length of the combined lens changes according to the focal length of each convex lens. The cross-sectional shape of the primary laser light at the position of the mask is just circumscribed or slightly larger than the mask by appropriately setting the intersection angle of the axial plane, the position of the mask, and the focal length of each convex lens. Therefore, even if the shape and size of the mask are different, the mounting and dismounting of the expander 4 and the reducer 8 necessary for the above-described conventional marking device 16 and the optical axis of these Imprinting can be performed immediately without performing the operation of attaching and detaching optical parts such as adjustment, and the cross-sectional area of the primary laser beam can be reduced to the required area as in the case of the engraving performed by removing the reducer 8 from the conventional device 16. Since the present invention does not need to have a large area as much as four times, the present invention is easy to handle and has different shapes without attaching and detaching optical components.
There is an effect that a laser engraving device that can extend the life of a light excitation lamp in a laser beam generator while being an engraving device that can be used for a mask having a size is obtained.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an embodiment of the present invention.

FIG. 2 is an explanatory view of one embodiment of the combination lens shown in FIG.

FIG. 3 is an explanatory view of an embodiment different from the embodiment shown in FIG. 2 of the combination lens shown in FIG. 1;

FIG. 4 is a functional explanatory view of the combination lens of the embodiment shown in FIG. 2;

FIG. 5 is a functional explanatory view of the combination lens of the embodiment shown in FIG. 3;

FIG. 6 is an explanatory view of a cross section of a primary laser beam in a conventional laser marking device.

FIG. 7 is a configuration diagram of a conventional laser marking device.

[Explanation of symbols]

 Reference Signs List 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 surface 20 laser beam generator 21 laser light emission Part 22 Primary laser light 23 Secondary laser light 26 Laser marking device

Claims (3)

(57) [Claims] 1. A lens comprising two thin cylindrical convex lenses disposed close to each other such that their optical axes coincide with each other, wherein said biconvex lens is formed so as to be relatively rotatable around said lens optical axis. Combination lens and
A laser beam generator for generating a laser beam having a circular cross section of a predetermined diameter and causing the laser beam to enter the combination lens such that the beam optical axis of the laser beam coincides with the lens optical axis; A mask on which the primary laser light transmitted through the lens is made incident, and a laser light emitting unit for irradiating the work with the secondary laser light passing through the mask, wherein the shape of the mask and the size of the lens By appropriately setting the intersection angle of both optical axis surfaces, the position of the mask, and the focal length of each convex lens, an engraving pattern corresponding to the mask pattern provided on the mask is engraved on the work at a time. Laser marking device. 2. A mask type laser engraving apparatus according to claim 1, wherein the two thin cylindrical convex lenses forming the combination lens have the same focal length. 3. The engraving device according to claim 2, wherein the focal length of the combined lens is changed from a combined lens in which each posture of the biconvex lens is set such that the respective optical axis surfaces of the biconvex lens are in the same plane. A mask-type laser engraving apparatus, wherein a mask is arranged at a position on a lens optical axis at a distance of about ／.