KR101542018B1 - Method for laser machining with optimized moving route - Google Patents

Abstract

The present invention relates to a laser processing method having an optimized movement route, which forms a plurality of holes on a workpiece substrate, and comprises: a processing scope setting step of setting a processing scope which is formed by an arrival area of the laser reflected by incidence with a reflective mirror; a loading step of loading information on a location having a reference point which has a location corresponded to a location of the holes formed on the workpiece substrate; a reference location setting step of removing a reference point from an area where the intensity of the reference point included in the processing scope in the location information is highest and setting the center point of the processing scope as a reference point; a movement route creating step of creating a movement route of the workpiece substrate from the reference location; and a processing step of performing laser processing while moving the workpiece substrate along the movement route. Accordingly, the processing scope is set through the reflective mirror capable of rotating during the laser processing, the holes included in the processing scope is processed, then the workpiece substrate is moved, and the movement route of the workpiece substrate is minimized, thereby reducing a time consumed for forming the holes on the workpiece substrate.

Description

METHOD FOR LASER MACHINING WITH OPTIMIZED MOVING ROUTE [0002]

The present invention relates to a laser processing method having an optimized movement path, and more particularly, to a laser processing method and a laser processing method for minimizing the time required for forming a plurality of holes in a workpiece To a laser processing method having an optimized movement path.

2. Description of the Related Art Recently, electronic devices such as smart phones, notebooks, and tablets have been required to be lightweight and miniaturized, so that there is a demand for a flexible printed circuit board (FPCB) capable of overcoming the limitations of conventional printed circuit boards Increase.

Conventionally, a mechanical drill has been used to process small holes and special via holes corresponding to interlayer connection paths of a multilayer printed circuit board. However, in the case of a flexible circuit board, a laser processing apparatus is mainly used.

The laser processing apparatus is a device for drilling a small hole and a special via hole using a laser beam for connection between layers in an electronic device of a multilayer substrate. The laser machining apparatus is mainly used because it can overcome the problems of mechanical drilling which has problems such as peeling of a flexible circuit board or cracking of a terminal. In addition, due to the miniaturization of the circuit, the diameter of the hole has become smaller, and due to the increase of the processing cost and the limitation of fine hole machining, the laser processing method has been used as an alternative.

1 is a schematic conception diagram of laser processing. 1 (a), in the laser drilling apparatus, a laser beam emitted from a laser irradiation unit 110 is incident on a reflection mirror, reflected by a reflection mirror, and incident on a substrate 140 side. The laser beam incident on the substrate 140 forms a hole H such as a via hole on the substrate 140. At this time, the substrate 140 is mounted on the upper surface of the stage 150 and is movable along the X and Y axes.

Conventionally, a laser beam is irradiated on a substrate 140 in a state where the substrate 140 is stopped to process a hole at a desired position on the substrate 140. That is, when the substrate 140 is moved using the stage 150 and the portion to be processed on the substrate 140 is within the maximum working range of the laser beam, the substrate 140 ). Thereafter, the substrate 140 is irradiated with a laser beam in a stationary state at a target position. When the machining of the machining holes H in the work area is completed, the substrate 140 is moved again such that another part of the substrate 140 enters the work area. This method is excellent in terms of positional accuracy of machining.

However, the substrate 140 moves along the movement path shown in FIG. 1 (b) by the stage 150. The process of moving the substrate → stopping the substrate → processing the hole → moving the substrate again is repeated. Since the moving path of the substrate 140 is fixed, the above process is performed until the processing is unnecessary, There was a considerable increase in this problem.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to solve such conventional problems, and it is an object of the present invention to provide a method and apparatus for processing a plurality of holes included in a machining range after setting a machining range through a reflective mirror, The present invention also provides a laser processing method having an optimized moving path that can reduce the time required to form a plurality of holes in a workpiece by minimizing the moving path of the workpiece.

According to the present invention, there is provided a laser machining method for forming a plurality of holes in a workpiece, comprising: a machining range setting step of setting a machining range formed by an arrival area of a laser incident on and reflected by a reflecting mirror; A loading step of loading position information on which a reference point having a position corresponding to a position of a plurality of holes formed in the workpiece is formed; A reference position setting step of setting a center point of the machining range as a reference position after removing a reference point in an area having the highest density of the reference points included in the machining range from the positional information; A moving path generating step of generating a moving path of the measured substrate from the reference position; And a processing step of performing laser processing while moving the processed substrate in accordance with the movement path. The present invention also provides a laser processing method having an optimized movement path.

Here, it is preferable that the reference position setting step uses a Delaunay triangulation or a Voronoi diagram to find the region having the highest density of the reference point.

Here, the reference position setting step sets a reference position when all of the reference points are erased, and sets the reference point in the range of reference from the remaining reference points when the reference points are not all erased. It is desirable to remove reference points within the high area.

Here, the movement path generation step may include: a main movement path generation step of generating a main movement path from the reference position; And a detailed movement path generating step of generating a processing sequence of reference points in which each of the reference positions is included in the set machining range.

Here, it is preferable that the movement route generation step is generated using a traveling salesperson problem (TSP) method.

Here, the machining range setting step preferably irradiates the laser with the reflection mirror so that the machining range becomes a square.

According to the present invention, there is provided a laser processing method having an optimized travel path that can reduce the time required to form a plurality of holes in a workpiece by minimizing the travel path of the workpiece.

In addition, since the time required to form a plurality of holes is reduced, the unit cost of the product is lowered and the overall production amount is increased.

In addition, since the movement of the stage is minimized, an error caused by the movement of the stage can be reduced.

1 is a schematic diagram of a laser processing,
2 is a flowchart of a laser processing method having an optimized movement path according to an embodiment of the present invention,
Fig. 3 is an algorithm of the laser processing method having the optimized movement path of Fig. 2,
Fig. 4 is a view schematically showing a laser processing apparatus used in a laser processing method having an optimized movement path of Fig. 2,
Fig. 5 is a view schematically showing the machining range setting step of the laser machining method having the optimized movement path of Fig. 2,
Fig. 6 is a view schematically showing reference point elimination of the laser processing method having the optimized movement path of Fig. 2,
FIG. 7 is a view schematically showing the Delone triangulation of the reference positioning step of the laser processing method having the optimized movement path of FIG. 2,
Fig. 8 is a view schematically showing a Voronoi diagram of the reference position setting step of the laser processing method having the optimized movement path of Fig. 2,
Fig. 9 is a schematic view showing the relationship between the Delone triangulation and the Voronoi diagram of the laser processing method having the optimized movement path of Fig. 2,
Fig. 10 is a view schematically showing the reference position setting of the laser processing method having the optimized movement path of Fig. 2,
FIG. 11 is a view schematically showing a main movement path generation step of the laser processing method having the optimized movement path of FIG. 2,
12 is a view schematically showing a detailed movement path generation step of the laser processing method having the optimized movement path of FIG.

Hereinafter, a laser processing method having an optimized movement path according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

According to an embodiment of the present invention, there is provided a laser processing method having an optimized movement path, comprising: setting a machining range through a rotatable reflective mirror during laser machining; processing a plurality of holes included in the machining range; To a laser processing method having an optimized moving path capable of reducing the time required for forming a plurality of holes in a workpiece by minimizing a moving path of the workpiece.

FIG. 2 is a flow chart of a laser processing method having an optimized movement path according to an embodiment of the present invention, FIG. 3 is an algorithm of a laser processing method having an optimized movement path of FIG. 2, Fig. 1 is a view schematically showing a laser machining apparatus used in a laser machining method having a movement path in which a laser beam is irradiated;

Referring to FIG. 2, a laser processing method S100 having an optimized movement path according to an embodiment of the present invention includes a machining range setting step S110, a loading step S120, a reference position setting step S130 (S140), and a machining step (S150).

The laser irradiation unit 110 includes a laser for forming a hole H on the evaporated substrate 140. The laser irradiation unit 110 is a laser processing unit Oscillation. The reflection mirror 120 reflects the laser beam emitted from the laser irradiation unit 110 and is provided so as to be rotatable by a predetermined angle to change the reflection angle of the laser beam, thereby forming a machining range having a predetermined area. The lens 130 has a structure in which the laser reflected from the reflection mirror 120 has a linearity and is incident on the evaporation material 140. In this embodiment, the evaporation material 140 is provided as a flexible circuit substrate. The stage 150 is configured to move the evaporated substrate 140, and the evaporated substrate 140 is seated on the upper surface.

Fig. 5 is a view schematically showing the machining range setting step of the laser machining method having the optimized movement path of Fig. 2; Referring to FIG. 5, the machining range setting step S110 is a step of setting a machining range A, which is a range in which a hole can be machined by a laser without moving the evaporation substrate 140. [ The laser emitted from the laser irradiation unit 110 is incident on and reflected by the reflective mirror 120 provided to be rotatable by a predetermined angle so that the reflective mirror 120 is rotated A range in which the laser reaches is formed. That is, the machining range A means an arrival region of the laser formed by the rotation of the reflection mirror 120.

In the present embodiment, the processing range A irradiates the laser to the reflection mirror 120 so as to be square. When the reflection mirror 120 is provided in a circular shape or the like, the laser incident on the edge of the reflection mirror 120 and reflected by the reflection mirror 120 is not excellent in reliability, so that an error or the like occurs in the hole H formed in the deposition base material 140 Lt; / RTI > Thus, in this embodiment, the reliability of the laser path incident on the evaporation substrate 140 is excellent by irradiating the laser so that the processing range A is square in one region of the central portion of the reflection mirror 120.

The loading step S120 is a step of loading the position information P formed with the reference point R having a position corresponding to the position of the plurality of holes H formed in the flexible circuit board as the evaporated substrate 140 . That is, the positions and the number of the reference points R formed on the position information P are the same as the positions and the number of the holes H formed in the evaporation substrate 140. Information on the plurality of holes H formed in the evaporation substrate 140 is stored in advance in a storage medium or the like, and the position information P is loaded from the storage medium.

The reference position setting step S130 sets the reference position C as a basis for generating the optimized movement path of the evaporation material 140 or the stage 150 from the reference point R displayed in the position information P .

Fig. 6 is a view schematically showing reference point elimination of the laser processing method having the optimized movement path of Fig. 2; The reference position setting step S130 is a step of setting the reference position R in the machining range A among the plurality of reference points R on the position information P at the reference point R The center point of the machining range A is set as the reference position C and this is performed until all the reference points R on the position information P are erased. The set reference position C is stored in the storage medium.

The processing range A is formed by the reflective mirror 120 which can be rotated by a predetermined angle and the reference position C is the center point of the processing range A. Therefore, The laser beam is reflected at right angles to be incident on the substrate 140 to be measured.

6A, a reference point R in a region having the highest density of a reference point R included in the machining range A among a plurality of reference points R on the position information P, Lt; / RTI > 6 (b), the reference points R in the region having the highest density of the reference points R included in the machining range A among the remaining reference points R are erased.

The region with the highest density of reference point (R) is found through Delaunay triangulation or Voronoi diagram.

FIG. 7 is a diagram schematically showing a Delone triangulation of the reference position setting step of the laser processing method having the optimized movement path of FIG. 2; FIG. Delone triangulation means a division that divides the space by connecting the points on the plane with a triangle so that the minimum value of the interior angles of these triangles is maximized. Assuming that there are a plurality of points on a plane as shown in FIG. 6 (a), a method of connecting the points to form a triangle is as shown in FIGS. 7 (b) and 7 (c). At this time, by dividing the triangles so that the minimum value of the interior angle of the triangles is the maximum, that is, by dividing the triangles as close to the equilateral triangle as possible, "the circumcircle of any triangle does not include any points other than the three vertices of the triangle." Thus, it is judged that the density of the reference point C is the highest in the region where the number of triangles included in the machining range A is largest.

FIG. 8 is a view schematically showing a Voronoi diagram of the reference position setting step of the laser processing method having the optimized movement path of FIG. 2. FIG. The Voronoi diagram is a diagram of a plane divided by the distance from some seed points. The Voronoi diagram for a given seed point on the plane divides the region according to which seed point is closest to the seed point It means one diagram. When there is a seed point on the plane as shown in Fig. 8A, a Voronoi diagram as shown in Fig. 8B is derived.

Fig. 9 is a schematic view showing the relationship between the Delone triangulation and the Voronoi diagram of the laser processing method having the optimized movement path of Fig. 2; Fig. The trine triangulation and the Voronoi diagram are in pair relation. To explain this, the Voronoi diagram is derived by connecting the centers of the circumscribed circles of the obtained triangles after finding the Amore triangulation with each seed point in the Voronoi diagram. Concretely, if the centers of the circumscribed circles of the Neuron triangles having a common vertex are connected in order, the Voronoi region having the common point as the seed is derived. On the other hand, connecting the seed points between the Voronoi regions adjacent to each other results in an Orrone triangulation for these seed points.

That is, in the present embodiment, the reference position setting step S130 is a step of setting the reference position R within a range of the reference point R included in the machining range A among the plurality of reference points R on the position information P The center point of the machining range A is set as the reference position C after erasing the reference points R and is performed until all the reference points R on the position information P are erased. At this time, the region having the highest density of the reference point (R) is searched using any of the Delone triangulation or the Voronoi diagram. However, the present invention is not limited to the Delaunay triangulation or the Voronoi diagram, and other methods for finding the region having the highest density of the reference point R within the machining range A are also applicable.

Fig. 10 is a view schematically showing the reference position setting of the laser processing method having the optimized movement path of Fig. 2; After the reference point R in the region having the highest density of the reference point R included in the machining range A among the plurality of reference points R on the position information P is erased, Is set to the reference position C and is stored in the storage medium. The reference points R in the area having the highest density of the reference points R included in the machining range A are sequentially subjected to erasure to erase all the reference points R, Is loaded from the storage match as shown in FIG.

The movement path generation step S140 is a step of generating an optimized movement path of the measured subject 140 from the loaded reference position (C) information. As described above, the movement of the target substrate 140 is achieved by the movement of the stage 150 on which the target substrate 140 is placed.

11 is a view schematically showing a main movement path generation step of the laser processing method having the optimized movement path of FIG. The main movement path L1 is an optimized movement path of the measured substrate 140 according to the machining range A. [

개가 된다. 그러나, 본 실시예에서는 피측정기재(140)가 기준위치(C)를 따라 이동하여야 하므로, 피측정기재(140)가 이동하여야 하는 경우의 수는 상당히 줄어들게 된다. 즉, 피측정기재(140) 상의 홀(H)의 개수가 아닌 피측정기재(140) 상의 가공범위(A)의 개수로부터 경우의 수가 산출되므로, 매우 신속하게 주 이동경로(L1)가 산출된다.Assuming that N holes H are formed in the measured substrate 140, the number of cases in which the measured substrate 140 needs to move in order to process the N holes H is

Dogs. However, in the present embodiment, since the substrate 140 to be measured must move along the reference position C, the number of cases in which the substrate 140 is required to move is significantly reduced. That is, the number of cases is calculated from the number of processing areas A on the substrate 140 to be measured, which is not the number of holes H on the measurement target substrate 140, so that the main movement path L1 is calculated very quickly .

On the other hand, the main movement path L1 of the measured substrate 140 is calculated through a traveling salesman problem (TSP). There are many known methods for solving the traveling salesman problem, and any of them can be used.

12 is a view schematically showing a detailed movement path generation step of the laser processing method having the optimized movement path of FIG. Referring to Fig. 12, the detailed movement path L2 is a visualization of the order of forming each hole H in the machining range A, as shown in Fig. The detailed movement path (L2) is also calculated through circulating salesmen.

That is, the detailed movement path L2 does not actually move the substrate 140 but shows the machining order of a plurality of holes H included in each machining range A.

That is, the movement path generation step S140 is a step of generating the main movement path L1 on which the measured substrate 140 moves on the basis of each machining range A, Which is a processing order of the holes H of the first and second holes.

The processing step S150 is a step of forming the holes H on the substrate 140 while the stage 150 moves along the main movement path L1 generated in the movement path generating step S140.

The stage 150 is positioned in the starting machining range A of the main movement path L1 and then machined in the machining range A along the detailed movement path L2 and the machining ranges A, And then reaches the next reference position C along the main movement path L1 and thereafter the respective holes are machined along the detailed movement path L2 within the machining range A . At this time, when the holes are formed, that is, in the detailed movement path (L2), the substrate to be measured 140 is stopped.

That is, not only the optimization of the moving path of the measured substrate 140, but also the hole machining sequence are optimized.

Therefore, according to the present invention, after setting the machining range through the rotatable reflection mirror during laser machining, a plurality of holes included in the machining range are machined, the machined substrate is moved, and the moving path of the machined substrate is minimized There is provided a laser processing method having an optimized movement path that can reduce the time required for forming a plurality of holes in a workpiece.

The scope of the present invention is not limited to the above-described embodiments, but may be embodied in various forms of embodiments within the scope of the appended claims. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the appended claims.

S100: Laser processing method with optimized travel path
S110: machining range setting step S120: loading step
S130: Reference position setting step S140: Move path creation step
S150: Processing step 110: Laser irradiation part
120: reflection mirror 130: lens
140: Measuring substrate 150: stage
A: Machining range C: Reference position
R: Reference point P: Location information

Claims (6)

A laser processing method for forming a plurality of holes in a workpiece,
A machining range setting step of setting a machining range formed by an arrival area of the laser incident on and reflected by the reflection mirror;
A loading step of loading position information on which a reference point having a position corresponding to a position of a plurality of holes formed in the workpiece is formed;
A reference position setting step of setting a center point of the machining range as a reference position after removing a reference point in an area having the highest density of the reference points included in the machining range from the positional information;
A movement path generation step of generating a movement path of the workpiece from the reference position;
And a processing step of performing laser processing while moving the processed substrate in accordance with the movement path,
Wherein the reference position setting step uses a Delaunay triangulation or a Voronoi diagram to find an area having the highest density of the reference points, . delete The method according to claim 1,
Wherein the reference position setting step sets a reference position when all of the reference points are erased, and sets a reference position when the reference points are not all erased, And the reference point in the laser beam is removed. The method according to claim 1,
The movement path generation step may include:
A main movement path generating step of generating a main movement path from the reference position; And a detailed movement path generation step of generating a machining sequence of reference points in which each of the reference positions is included in the set machining range. 5. The method of claim 4,
Wherein the movement path generation step is generated using a traveling salesperson problem (TSP) method. The method according to claim 1,
Wherein the machining range setting step irradiates the laser with the reflection mirror so that the machining range becomes a square.

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