Marking device and marking method

Abstract

To mark a nonplanar part of a medium with high quality.SOLUTION: A marking device marks a nonplanar part of a medium, wherein the nonplanar part has a plurality or regions including a first region and a second region, and has a first marking part for performing the marking by condensing first light onto the first region by a first optical system and a second marking part for performing the marking by condensing second light onto the second region by a second optical system, and a second condensing position by the second optical system is different from a first condensing position by the first optical system in a direction along a central axis of the first optical system.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a marking device. , and and marking methods. [Background technology]

[0002] 2. Description of the Related Art Conventionally, media including identification codes such as barcodes and QR codes (registered trademarks), characters, symbols, marks, and other designs are known.

[0003] Also, in a marking device that draws a predetermined drawing pattern in a marking area set on a workpiece, a configuration is disclosed in which a first marking unit that marks the workpiece with a first dot diameter and a second marking unit that marks the workpiece with a second dot diameter smaller than the first dot diameter are used, and the drawing pattern within the same area is divided into a first drawing pattern drawn by the first marking unit and a second drawing pattern drawn by the second marking unit and marked (see, for example, Patent Document 1). Summary of the Invention [Problem to be solved by the invention]

[0004] However, the configuration of Patent Document 1 leaves room for improvement in the quality of marking performed on non-flat surfaces of media such as workpieces.

[0005] An object of the present invention is to perform high quality marking on a non-flat portion of a medium. [Means for solving the problem]

[0006] A marking device according to one aspect of the present invention is a marking device that marks a non-planar portion of a medium, the non-planar portion having a plurality of regions including a first region and a second region, The marking device includes a first marking section that performs the marking by converging a first light on the first region by a first optical system, and a second marking section that performs the marking by converging a second light on the second region by a second optical system, and a second converging position by the second optical system is different from a first converging position by the first optical system in a direction along a central axis of the first optical system. the non-flat portion has a curvature along a predetermined curvature direction, and the greater the maximum height difference within each of the plurality of regions in a direction along a central axis of the first optical system, the smaller the width of each of the regions in the curvature direction. .

[0007] A marking device according to one embodiment of the present invention is a marking device that performs marking on a non-planar portion of a medium, the non-planar portion having a plurality of regions including a first region and a second region, and has a first marking section that performs the marking by focusing a first light on the first region by a first optical system, and a second marking section that performs the marking by focusing a second light on the second region by a second optical system, wherein a central axis of the first optical system is perpendicular to a surface of the first region, and a central axis of the second optical system is perpendicular to the surface of the second region and non-parallel to the central axis of the first optical system.

[0008] A marking device according to one embodiment of the present invention is a marking device that performs marking on a non-planar portion of a medium, the medium being transported in a predetermined transport direction, the non-planar portion having a plurality of regions including a first region and a second region, the marking device having a first marking section that performs the marking by focusing a first light on the first region by a first optical system, a second marking section that performs the marking by focusing a second light on the second region by a second optical system, and a variable section that is provided between the first marking section and the second marking section along the transport direction and that changes an orientation of the non-planar portion, the second marking section performing the marking on the second region after the first marking section performs the marking on the first region and the variable section changes the orientation of the non-planar portion. Effect of the Invention

[0009] According to the present invention, high quality marking can be performed on a non-flat portion of a medium. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a diagram illustrating marking on a PET bottle. [Diagram 2] 1 is a diagram illustrating an example of the configuration of a marking device according to a first embodiment. [Diagram 3] 4 is a block diagram showing an example of a functional configuration of a control unit according to the first embodiment. FIG. [Figure 4] FIG. 13 is a diagram showing another example of the marking configuration. [Diagram 5] 1 is a diagram showing an example of differences in width of each region along the circumferential direction of a PET bottle. [Figure 6] FIG. 11 is a diagram illustrating an example of the configuration of a marking device according to a second embodiment. [Figure 7] FIG. 13 is a diagram illustrating an example of the configuration of a marking device according to a third embodiment. [Figure 8] 8A and 8B are diagrams showing examples of marking by the marking device according to the third embodiment, in which FIG. 8A shows marking in a first region, and FIG. 8B shows marking in a second region. [Figure 9] FIG. 13 is a diagram illustrating an example of the configuration of a marking device according to a fourth embodiment. [Figure 10] FIG. 13 is a diagram showing another example of the configuration of the marking device according to the fourth embodiment. [Figure 11] FIG. 1 is a diagram illustrating marking on a polygonal cylindrical PET bottle. [Figure 12] FIG. 2 is a diagram illustrating an example of a container according to an embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In each drawing, the same components are denoted by the same reference numerals, and duplicated explanations will be omitted as appropriate.

[0012] Furthermore, the embodiments shown below are merely examples of a marking device for embodying the technical concept of the present invention, and the present invention is not limited to the embodiments shown below. The dimensions, materials, shapes, relative positions, etc. of the components described below are intended to be illustrative, and are not intended to limit the scope of the present invention, unless otherwise specified. Furthermore, the sizes and positional relationships of the components shown in the drawings may be exaggerated in order to clarify the explanation.

[0013] The marking device according to the embodiment performs marking on a non-flat portion of a medium. Here, the medium includes, as an example, a container or the like. The container refers to a member capable of containing a substance such as a solid, liquid, or gas inside. For example, the container is a PET (polyethylene terephthalate) bottle. The substrate refers to a material portion that constitutes the container. The substrate may be composed of a transparent material such as resin or glass.

[0014] A transparent material is a material that is optically transparent to at least visible light. Visible light is light that is visible to humans and has a lower wavelength of approximately 360 nm to approximately 400 nm and an upper wavelength of approximately 760 nm to approximately 830 nm.

[0015] Resin materials used for the substrate include polyethylene terephthalate, polyvinyl alcohol (PVA), polybutylene adipate / terephthalate (PBAT), polyethylene terephthalate succinate, polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), polyvinyl chloride (PVC), polystyrene (PS), polyurethane, epoxy, bio-polybutylene succinate (PBS), polylactic acid blend (PBAT), starch blend polyester resin, polybutylene terephthalate succinate, polylactic acid (PLA), polyhydroxybutyrate / hydroxyhexanoate (PHBH), polyhydroxyalkanoate (PHA), bio-PET30, bio-polyamide (PA) 610, 410, 510, bio-PA1012, 10T, bio-PA11T, MXD10, bio-polycarbonate, bio-polyurethane, bio-PE, bio-PET100, bio-PA11, bio-PA1010, etc.

[0016] The container may include a main body for containing the object to be contained, as well as a cap, a lid, etc. In addition to the identification code, characters indicating the object to be contained or the manufacturer, etc., or graphics such as a brand logo or a recycle mark may be formed on the base material.

[0017] Moreover, a container that contains an item such as a beverage is called a container.

[0018] Marking refers to the formation of a design on a medium. Designs include identification codes, characters, symbols, and marks. Identification codes include one-dimensional codes such as barcodes, and two-dimensional codes such as QR codes. The content formed by marking is a symbol, figure, or character that displays information about the object, such as the name or identification number of the container to which an identification code is assigned or the object to be contained in the container, the manufacturer, and the date and time of manufacture.

[0019] The term "non-flat portion" refers to a portion that is not flat. For example, the non-flat portion corresponds to a non-flat portion included in a three-dimensional structure such as a PET bottle formed in a cylindrical or polygonal tubular shape. More specifically, the non-flat portion corresponds to a side surface of a PET bottle or an uneven portion formed on the side surface.

[0020] In an embodiment, the non-planar portion has a plurality of regions including a first region and a second region, and the marking device has a first marking section that performs marking by focusing a first light on the first region by a first optical system, and a second marking section that performs marking by focusing a second light on the second region by a second optical system.

[0021] The first and second regions included in the non-flat portion are located at different positions in a direction along the central axis of the first optical system. Therefore, in the direction, when the second light collecting position by the second optical system is equal to the first light collecting position by the first optical system, the second light spreads on the second region. In addition, since the first and second regions are non-parallel to each other, when the central axis of the second optical system is approximately parallel to the central axis of the first optical system, the central axis of the second optical system is tilted with respect to the second region, and the second light spreads on the second region.

[0022] As a result, the quality of marking on the second region may be degraded. The focusing position refers to a position where light is focused by an optical system. For example, when focusing laser light, the beam waist position corresponds to an example of the focusing position. However, the focusing position is not limited to the beam waist position, and may be a so-called defocus position that is shifted from the beam waist position.

[0023] In the embodiment, in the direction along the central axis of the first optical system, the second light collecting position by the second optical system is different from the first light collecting position by the first optical system. This allows the first marking portion to collect the first light on the first region, and the second marking portion to collect the second light on the second region, thereby enabling high-quality marking on both the first and second regions.

[0024] In another embodiment, the central axis of the first optical system is perpendicular to the surface of the first region, and the central axis of the second optical system is perpendicular to the surface of the second region and non-parallel to the central axis of the first optical system. This allows the first optical system to focus the first light so that its central axis is perpendicular to the surface of the first region, and the second optical system to focus the second light so that its central axis is perpendicular to the surface of the second region, thereby enabling high-quality marking on both the first and second regions. Note that non-parallel means not parallel. Also, orthogonal does not require strict orthogonality, and a deviation from orthogonality that is generally recognized as an error is allowed. This point is also applicable to the case of "orthogonal" hereinafter.

[0025] In another embodiment, the medium is transported in a predetermined transport direction, and the second marking unit performs marking on the second region after the first marking unit performs marking on the first region and changes the orientation of the non-flat portion. This allows the first optical system to focus the first light so that its central axis is perpendicular to the surface of the first region, and the second optical system to focus the second light so that its central axis is perpendicular to the surface of the second region, allowing high-quality marking on both the first and second regions.

[0026] Each embodiment will be described in detail below.

[0027] In the figures shown below, directions may be indicated by the X, Y, and Z axes, but the direction in which the arrow points in the X direction is indicated as the +X direction, the opposite direction of the +X direction is indicated as the -X direction, the direction in which the arrow points in the Y direction is indicated as the +Y direction, the opposite direction of the +Y direction is indicated as the -Y direction, the direction in which the arrow points in the Z direction is indicated as the +Z direction, and the opposite direction of the +Z direction is indicated as the -Z direction. However, this does not limit the orientation of the marking device when in use, and the orientation of the marking device is arbitrary.

[0028] Fig. 1 is a diagram for explaining marking on a PET bottle. As shown in Fig. 1, a PET bottle 100 is a cylindrical member with a pattern 200 marked on the side, and is an example of a medium.

[0029] 1 indicates a direction along the cylindrical axis of the PET bottle 100, the X-axis indicates a direction substantially perpendicular to the Y-axis, and the Z-axis indicates a direction substantially perpendicular to both the X-axis and the Y-axis. The directions indicated by the X-axis, Y-axis, and Z-axis are the same in the subsequent figures.

[0030] The side surface of the PET bottle 100 is a curved surface having a curvature around the cylindrical axis. The curved portion 110 of the side surface of the PET bottle 100 is an example of a non-flat portion that includes a first region 101, a second region 102, and a third region 103.

[0031] The first region 101, the second region 102, and the third region 103 are examples of a plurality of regions arranged around the cylindrical axis on the side portion of the PET bottle 100, and the regions do not overlap with each other. In other words, the first region 101 includes a non-overlapping region that does not overlap with the second region 102. However, this is not limited to this, and the regions may at least partially overlap with each other.

[0032] Pattern 200 is an example of a design. In the example of Fig. 1, pattern 200 is a pattern showing flower petals. Pattern 200 is marked by modifying the base material of PET bottle 100 by evaporation, melting, crystallization, foaming, or the like, using the optical energy of the laser light focused on each of first region 101, second region 102, and third region 103. The marking device according to the embodiment is a device that performs such marking.

[0033] [First embodiment] <Configuration example of marking device 1> Fig. 2 is a diagram showing an example of the configuration of the marking device 1 according to the first embodiment. Fig. 2 shows a PET bottle 100 and the marking device 1 as viewed from the +Y direction side. Note that the marking device 1 is shown with the interior seen through.

[0034] 2, the marking device 1 has a first marking unit 10, a second marking unit 20, a third marking unit 30, and a control unit 40. Based on the received image data, the marking device 1 performs marking on a first region 101 by the first marking unit 10, on a second region 102 by the second marking unit 20, and on a third region 103 by the third marking unit 30.

[0035] The first marking unit 10 has a first laser light source 11, a first condenser lens 12, and a first galvanometer mirror 13. The first marking unit 10 performs marking by raster scanning the first laser light L1 emitted by the first laser light source 11 in a direction along the Y axis by the first galvanometer mirror 13 and condensing the scanned first laser light L1 on a first region 101 by the first condenser lens 12. The first condenser lens 12 is an example of a first optical system, and the first laser light L1 is an example of a first light.

[0036] The second marking unit 20 has a second laser light source 21, a second condenser lens 22, and a second galvanometer mirror 23. The second marking unit 20 performs marking by raster scanning the second laser light L2 emitted by the second laser light source 21 in a direction along the Y axis by the second galvanometer mirror 23 and condensing the scanned second laser light L2 on the second region 102 by the second condenser lens. The second condenser lens 22 is an example of a second optical system, and the second laser light L2 is an example of a second light.

[0037] The third marking unit 30 has a third laser light source 31, a third condenser lens 32, and a third galvanometer mirror 33. The third marking unit 30 performs marking by raster scanning the third laser light L3 emitted by the third laser light source 31 in a direction along the Y axis by the third galvanometer mirror 33 and condensing the scanned third laser light L3 on a third region 103 by the third condenser lens.

[0038] The first marking section 10, the second marking section 20 and the third marking section 30 can perform marking on the curved surface section 110 in parallel.

[0039] In addition, as the PET bottle 100 is transported in a transport direction 400 along the X-axis, the relative position along the X-axis between the PET bottle 100 and the focused position of the laser light by each marking unit and the focused position of the laser light by each marking unit changes. This allows marking to be performed over the entirety of each of the first region 101, the second region 102, and the third region 103.

[0040] The first laser light source 11, the second laser light source 21, and the third laser light source 31 are all fiber lasers that emit short pulse laser light of picoseconds, nanoseconds, etc. The fiber laser is a laser light source that uses an optical fiber doped with a rare earth element as a laser medium.

[0041] However, each laser light source is not limited to a fiber laser, and various laser light sources can be used. The laser light emitted by each laser light source may be a pulsed light or a CW (Continuous Wave), but from the viewpoint of peak energy, etc., it is preferable that the laser light source can be pulsed in a range of picoseconds to nanoseconds.

[0042] Solid-state lasers include YAG lasers and titanium sapphire lasers. Gas lasers include argon lasers, helium neon lasers, and carbon dioxide gas lasers. Semiconductor lasers are also suitable because of their small size. Fiber lasers are a more suitable light source because of their high peak energy and the possibility of miniaturization.

[0043] The first laser light source 11, the second laser light source 21, and the third laser light source 31 may each be a laser light source of a different type.

[0044] The first condenser lens 12, the second condenser lens 22, and the third condenser lens 32 are all refractive single lenses of the same shape and fθ lenses with the same focal length. The fθ lens has a function of condensing the laser light while scanning it at a constant speed. The fθ lens may be made of glass or resin, but in the embodiment, glass is more preferable because the light energy of the laser light is large.

[0045] The first condenser lens 12, the second condenser lens 22, and the third condenser lens 32 are not limited to the above as long as they are optical systems that condense light. For example, a diffractive lens or a mirror having a condensing function can be used, and a plurality of lenses or mirrors can be combined. In addition, the shapes of the condenser lenses and the optical characteristics such as the focal length can be different.

[0046] The first galvanometer mirror 13, the second galvanometer mirror 23, and the third galvanometer mirror 33 all scan the laser light in a direction along the Y axis by changing the angle of the mirror. The scanning direction is not limited to the Y axis direction, and scanning may be performed in the X axis direction or in two axial directions of the X axis and the Y axis. However, scanning in a direction along the longitudinal direction of the first region 101, the second region 102, and the third region 103 is more preferable in terms of marking efficiency. In addition to the galvanometer mirror, a polygon mirror, an acousto-optical element, a MEMS mirror, or the like may also be used.

[0047] The control unit 40 is a control device capable of controlling each of the first marking unit 10, the second marking unit 20, and the third marking unit 30.

[0048] <Laser light focusing position by each marking part> 2, the first region 101, the second region 102, and the third region 103 are each indicated by a thick arrow. As shown in Fig. 2, the position of each region along the Z-axis direction differs depending on the curvature around the cylindrical axis of the PET bottle 100. Compared to the first region 101 and the third region 103, the second region 102 is located closer to the marking device 1 along the Z-axis direction.

[0049] Therefore, when each of the first marking portion 10, the second marking portion 20, and the third marking portion 30 focuses the laser light at the same position along the Z-axis direction, the laser light may spread over each region.

[0050] For example, the second marking unit 20 focuses the second laser light L2 at the same position along the Z-axis direction as the focusing position of the first laser light L1 by the first marking unit 10. In this case, since the second region 102 is located just before the beam waist, the second laser light L2 is irradiated to the second region 102 in a broadened state. This reduces the resolution of the pattern marked in the second region 102, and the marking quality.

[0051] Therefore, in this embodiment, the second condenser lens 22 is arranged to be shifted by a distance d in the +Z direction compared to the first condenser lens 12 and the third condenser lens 32. The distance d can be determined in advance based on the curvature of the curved portion 110.

[0052] Thereby, the second marking plane 112 by the second condenser lens 22 is shifted in the +Z direction by the distance d with respect to the first marking plane 111 by the first condenser lens 12 and the third marking plane 113 by the third condenser lens 32. As a result, the second laser light L2 can be condensed so as to form a beam waist on the second region 102.

[0053] Here, the marking plane refers to a plane on which the marking unit performs marking by changing the focusing position of the laser light by either scanning the laser light or conveying the PET bottle. The position of the marking plane in the direction along the Z axis is equal to the focusing position of the laser light by the marking unit. Therefore, the first marking plane 111 is an example of the first focusing position by the first focusing lens 12, and the second marking plane 112 is an example of the second focusing position by the second focusing lens 22. Note that in FIG. 2, each marking plane is indicated by a thick dashed line.

[0054] Moreover, the central axis 51 of the first collecting lens 12 is aligned along the Z-axis. In other words, the second marking plane 112 is different from the first marking plane 111 in the direction along the central axis 51. The central axis 51 is, for example, the optical axis of the first collecting lens 12.

[0055] Here, the first region 101, the second region 102, and the third region 103 are each a curved surface, and each region has a height difference (position difference) in the direction along the central axis 51, and therefore does not coincide with the marking plane. Therefore, the laser light spreads according to the height difference between each region and the marking plane in the direction along the central axis 51.

[0056] In this embodiment, the position of each marking portion on the PET bottle 100 in the direction along the central axis 51 is determined so that the marking plane is located at the center of the height difference within each region. This suppresses the spread of the laser light according to the height difference between each region and the marking plane in the direction along the central axis 51.

[0057] 2, the first region 101 and the third region 103 have inclined surfaces, so that the difference in elevation within each region is large. The first marking plane 111 and the second marking plane 112 are disposed at positions that are the centers of the difference in elevation within the first region 101 and the third region 103.

[0058] <Example of functional configuration of control unit 40> Next, Fig. 3 is a block diagram showing an example of a functional configuration of the control unit 40 of the marking device 1. As shown in Fig. 3, the control unit 40 has a receiving unit 41, a correction unit 42, and a marking control unit 43. These functions are realized by electric circuits, and some or all of the functions can also be realized by software (CPU; Central Processing Unit). Each function may also be realized by multiple circuits or multiple software.

[0059] The control unit 40 receives image data from an external device such as a PC (Personal Computer) via the receiving unit 41, and controls each marking unit to perform marking based on the image data appropriately corrected by the correction unit 42 via the marking control unit 43.

[0060] In this embodiment, the spread of the laser light is minimized by arranging the marking plane at the center of the height difference in the region. However, in regions with large inclination of the surface such as the first region 101 and the third region 103, the spread of the laser light may become large, or the image of the marking target may be deformed when marked, which may result in a decrease in marking quality.

[0061] Correction unit 42 corrects the image data according to the shape of curved surface portion 110, such as the inclination of the surfaces in first region 101 and third region 103. For example, when an image is projected onto an inclined surface, keystone distortion occurs according to the inclination, so correction unit 42 corrects the image data by imparting keystone distortion opposite to that of the projected image to the image data so as to cancel out the keystone distortion.

[0062] The process of applying trapezoidal distortion to image data is a process of enlarging or reducing the line width for each line in the image data, and is therefore an example of a correction process that either enlarges or reduces the image represented by the image data.

[0063] It is more preferable from the viewpoint of improving the quality of the marking if the correction unit 42 corrects the image data so that the shading at the joint between the first region 101 and the second region 102 does not change or changes gradually.

[0064] The marking control unit 43 controls the on / off of the light emission or the light intensity of each of the first laser light source 11, the second laser light source 21, and the third laser light source 31. The marking control unit 43 also controls the start or stop of driving of the first galvanometer mirror 13, the second galvanometer mirror 23, and the third galvanometer mirror 33.

[0065] <Effects of the marking device 1> As described above, the marking device 1 according to this embodiment performs marking on the curved surface portion 110 (non-flat surface portion) of the PET bottle 100 (medium). The curved surface portion 110 has a plurality of regions including a first region 101 and a second region 102. The marking device 1 also has a first marking section 10 that performs marking by focusing a first laser light L1 (first light) on the first region 101 with a first focusing lens 12 (first optical system), and a second marking section 20 that performs marking by focusing a second laser light L2 (second light) on the second region 102 with a second focusing lens 22 (second optical system).

[0066] In the direction along the central axis 51 of the first condenser lens 12, the second marking plane (second condensing position) by the second condenser lens 22 differs from the first marking plane (first condensing position) by the first condenser lens 12.

[0067] As a result, even if the positions of the first region 101 and the second region 102 in the direction along the central axis 51 of the first collecting lens 12 are different, the first marking unit 10 can collect the first laser light L1 on the first region 101, and the second marking unit 20 can collect the second laser light L2 on the second region 102. As a result, the marking device 1 can perform high-quality marking on both the first region 101 and the second region 102.

[0068] For example, in the configuration of Patent Document 1, the marking conditions are changed to two conditions, large dots and small dots, in the same area, but in this embodiment, the marking conditions can be changed for each area, thereby improving the marking quality.

[0069] In this embodiment, the first region 101 includes a non-overlapping region that does not overlap with the second region 102, and the first marking unit 10 performs marking in parallel with the second marking unit 20. When marking is performed in a region where multiple marking units overlap, the productivity of the marking may decrease. By including a non-overlapping region in the first region 101, the first marking unit 10 can perform marking in parallel with the first region 101, and the second marking unit 20 can perform marking in parallel with the second region 102. This can improve the productivity of the marking.

[0070] However, this is not limiting, and the first region 101 may overlap with the second region 102. By overlapping, the first marking unit 10 and the second marking unit 20 can perform marking under different conditions in the same region.

[0071] Moreover, in this embodiment, a control unit 40 is provided that controls each of the first marking unit 10 and the second marking unit based on image data. The control unit 40 has a correction unit 42 that corrects the image data in accordance with the shape of the curved surface unit 110. For example, the correction unit 42 corrects the image data by either enlarging or reducing the image indicated by the image data.

[0072] Since the curved surface portion 110 is a curved surface, it does not coincide with the marking plane, and depending on the difference in height of the curved surface in the direction along the central axis 51 of the first focusing lens 12, the laser light may spread or the image of the target to be marked may be deformed and marked, which may result in a decrease in marking quality.

[0073] By correcting the image data according to the shape of the curved surface portion 110, for example, trapezoidal distortion of the image of the marking target can be corrected, and deterioration of the marking quality can be suppressed.

[0074] Furthermore, in this embodiment, the first marking unit 10 raster scans the first laser light L1 along the longitudinal direction of the first region 101, and the second marking unit 20 raster scans the second laser light L2 along the longitudinal direction of the second region 102. This allows high-speed marking in the longitudinal direction of each region, thereby further improving marking productivity.

[0075] However, each marking unit is not limited to one that raster scans laser light. Here, Fig. 4 is a diagram showing the configuration of a marking unit 10' as another configuration of the marking unit. The marking unit 10' is one of the multiple marking units included in the marking device 1. As shown in Fig. 4, the marking unit 10' has a laser array 11' and a condenser lens 12'.

[0076] The laser array 11' has a plurality of laser light sources arranged along the Y axis, and each of the plurality of laser light sources emits a laser beam in parallel toward the PET bottle 100. The focusing lens 12' is an example of a first or second optical system that focuses each of the plurality of laser beams emitted by the laser array 11' on the first region 101.

[0077] Even in a configuration in which each marking portion has such a laser array 11', the same effect as that achieved by raster scanning with laser light can be obtained.

[0078] In this embodiment, the first condenser lens 12, the second condenser lens 22, and the third condenser lens 32 have the same focal length, and the position of the second condenser lens 22 is shifted from the first condenser lens 12 in the direction along the central axis 51 of the first condenser lens 12. However, the means for making the first marking plane 111 and the second marking plane 112 different in the direction along the central axis 51 is not limited to this. For example, the focal length of the second condenser lens 22 may be shortened to make the second marking plane 112 different from the first marking plane 111. The same effect can also be obtained by displacing and arranging the second marking portion 20 itself in the direction along the central axis 51.

[0079] In the present embodiment, the configuration in which only the position of the second marking plane 112 differs from the others in the direction along the central axis 51 of the first collecting lens 12 has been exemplified, but the present invention is not limited to this. The positions of the first marking plane 111, the second marking plane 112, and the third marking plane 113 may differ in the direction along the central axis 51 depending on the arrangements of the first region 101, the second region 102, and the third region 103, respectively.

[0080] Furthermore, in this embodiment, the marking device 1 has three marking units and performs marking on three areas included in the curved surface portion 110, but the present invention is not limited to this. The marking device 1 may have more marking units and may perform marking on more areas included in a non-flat surface portion such as the curved surface portion 110.

[0081] In other words, the marking device 1 may have a plurality of marking sections (plurality of marking sections) including a first marking section 10 and a second marking section 20, and the focusing positions of the laser light by each of the plurality of marking sections may be configured to be different in the direction along the central axis 51 of the first focusing lens.

[0082] Although the curved surface portion 110 is shown as an example of a non-flat surface portion, the present invention is not limited thereto, and the non-flat surface portion may include irregularities or steps, and each of the first region 101, the second region 102, and the third region 103 may include irregularities or steps. In this case, the marking device 1 can provide the same effect.

[0083] <Modification of the First Embodiment> 2 illustrates an example in which the first region 101, the second region 102, and the third region 103 along the circumferential direction of the PET bottle 100 have approximately the same width. However, if the difference in height in the direction along the central axis 51 of the first collecting lens 12 increases due to a large inclination of each region, the spread of the laser light may increase according to the difference in height.

[0084] Therefore, the widths along the circumferential direction of the first region 101, the second region 102 and the third region 103 can be made different depending on the maximum height difference within each of the first region 101, the second region 102 and the third region 103 in the direction along the central axis 51 of the first focusing lens 12.

[0085] Fig. 5 is a diagram showing an example of the difference in width between the first region 101 and the second region 102 along the circumferential direction of the PET bottle 100. The circumferential direction 120 of the PET bottle 100 shown in Fig. 5 is an example of the curvature direction of the non-flat portion.

[0086] 5, in the direction along the central axis 51 of the first collecting lens 12, the maximum height difference h1 in the first region 101 is larger than the maximum height difference h2 in the second region 102. In addition, the width W1 of the first region 101 along the circumferential direction 120 is smaller than the width W2 of the second region 102 along the circumferential direction 120.

[0087] Since the maximum height difference h1 becomes smaller as the width W1 becomes smaller, the spread of the first laser light L1 according to the height difference is suppressed, and the marking quality on the first region 101 can be ensured to be higher.

[0088] 5 illustrates only the first region 101 and the second region 102, but is not limited thereto. When the non-flat portion includes a plurality of regions including the first region 101 and the second region 102, the width of each region in the curvature direction can be made smaller as the maximum height difference within each of the plurality of regions in the direction along the central axis 51 of the first collecting lens 12 increases. In this case as well, the same effect as that of the example shown in FIG. 5 can be obtained.

[0089] [Second embodiment] Next, a marking device 1a according to a second embodiment will be described. The same components as those described in the first embodiment will be given the same part numbers, and duplicated descriptions will be omitted as appropriate. This also applies to the following embodiments and modifications.

[0090] <Configuration example of marking device 1a> Fig. 6 is a diagram showing an example of the configuration of the marking device 1a. As shown in Fig. 6, the marking device 1a has a first marking unit 10a, a second marking unit 20a, and a third marking unit 30a.

[0091] The first marking portion 10a has a first condenser lens 12a, and the second marking portion 20a has a second condenser lens 22a. A central axis 51 of the first condenser lens 12 is perpendicular to the surface of the first region 101. A central axis 52 of the second condenser lens is perpendicular to the surface of the second region 102 and is non-parallel to the central axis 51 of the first condenser lens 12. Note that the perpendicularity is not limited to being strictly perpendicular, and an angle difference of ±5 degrees or less is acceptable. This point is also applicable to the use of the term perpendicular hereinafter.

[0092] <Function and effect of marking device 1a> 6, in the marking device 1a, the first condenser lens 12 can condense the first laser light L1 so that its central axis 51 is perpendicular to the surface of the first region 101, and the second condenser lens 22 can condense the second laser light L2 so that its central axis 52 is perpendicular to the surface of the second region 102. As a result, high-quality marking can be performed on both the first region 101 and the second region 102. Other effects are similar to those shown in the first embodiment.

[0093] It is preferable that the first focusing lens 12 focuses the first laser light L1 at approximately the center position of the first region 101 along the circumferential direction of the PET bottle 100 so that the central axis 51 of the first focusing lens 12 is perpendicular to the surface of the first region 101.

[0094] It is preferable that the second focusing lens 22 focuses the second laser light L2 at approximately the center position of the second region 102 along the circumferential direction of the PET bottle 100 so that the central axis 52 of the second focusing lens 22 is perpendicular to the plane of the second region 102.

[0095] [Third embodiment] Next, a marking device 1b according to a third embodiment will be described.

[0096] <Configuration example of marking device 1b> 7 is a diagram showing an example of the configuration of the marking device 1b. FIG 7 shows a state in which a PET bottle 100 is placed on a conveyor 300 and conveyed along a conveying direction 400.

[0097] As shown in Fig. 7, the marking device 1b has a manipulator 14. All five PET bottles shown in Fig. 7 represent the same PET bottle 100. Fig. 7 also shows PET bottles 100 whose positions along the conveying direction 400 change depending on the time as the PET bottle 100 is conveyed.

[0098] The manipulator 14 includes a first manipulator 141 and a second manipulator 142. The first manipulator 141 is provided between the first marking unit 10 and the second marking unit 20 along the conveying direction 400, and changes the orientation of the non-flat surface of the PET bottle 100.

[0099] The second manipulator 142 is provided between the second marking unit 20 and the third marking unit 30 along the conveying direction 400, and changes the orientation of the non-flat surface of the PET bottle 100. Each of the first manipulator 141 and the second manipulator 142 is an example of a variable unit. However, the variable unit is not limited to the manipulator 14, and may be any means that can realize the function of the variable unit.

[0100] <Example of operation of marking device 1b> The PET bottle 100 is conveyed by the conveyor 300 in the conveying direction 400, and is temporarily stopped at a position where the first region 101 faces the first marking unit 10 along the central axis 51 of the first condenser lens 12. The first marking unit 10 then performs marking on the first region 101.

[0101] Thereafter, the PET bottle 100 is conveyed along the conveying direction 400 by the conveyor 300 and is temporarily stopped at a position facing the first manipulator 141.

[0102] The first manipulator 141 grasps and lifts the temporarily stopped PET bottle 100, and rotates it around the cylindrical axis of the PET bottle 100. At this time, the first manipulator 141 changes the orientation of the curved surface portion 110 so that the surface of the second region 102 is perpendicular to the central axis 52 of the second condenser lens 22. The amount of change in the orientation can be determined in advance.

[0103] After changing the orientation of the curved surface portion 110, the first manipulator 141 places the PET bottle 100 on the conveyor 300.

[0104] Thereafter, the PET bottle 100 is conveyed by the conveyor 300 in the conveying direction 400, and is temporarily stopped at a position where the second region 102 faces the second marking unit 20 along the central axis 52 of the second condenser lens 22. Thereafter, the second marking unit 20 performs marking on the second region 102.

[0105] Thereafter, the PET bottle 100 is conveyed along the conveying direction 400 by the conveyor 300 and temporarily stopped at a position facing the second manipulator 142 .

[0106] The second manipulator 142 grasps and lifts the temporarily stopped PET bottle 100, and rotates it around the cylindrical axis of the PET bottle 100. At this time, the second manipulator 142 changes the orientation of the curved surface portion 110 so that the surface of the third region 103 is perpendicular to the central axis 53 of the second condenser lens 22. After changing the orientation of the curved surface portion 110, the second manipulator 142 places the PET bottle 100 on the conveyor 300.

[0107] Thereafter, the PET bottle 100 is conveyed by the conveyor 300 in the conveying direction 400, and is temporarily stopped at a position where the third region 103 faces the third marking unit 30 along the central axis 53 of the third condenser lens 32. Thereafter, the third marking unit 30 performs marking on the third region 103.

[0108] <Marking example> Fig. 8 is a diagram for explaining an example of marking by the marking device 1b. Fig. 8(a) shows a state in which the PET bottle 100 is conveyed by the conveyor 300 along the conveying direction 400 and is temporarily stopped at a position where the first region 101 faces the first marking unit 10 along the central axis 51 of the first condenser lens 12.

[0109] 8(a), the central axis 51 of the first condenser lens 12 is perpendicular to the surface of the first region 101. In this state, the first marking unit 10 performs marking on the first region 101.

[0110] In addition, it is preferable that the first manipulator 141 changes the orientation of the curved portion 110 so that the central axis 51 of the first focusing lens 12 is perpendicular to the surface of the first region 101 at approximately the center position of the first region 101 along the circumferential direction of the PET bottle 100.

[0111] Figure 8(b) shows the PET bottle 100 being transported by the conveyor 300 along the conveying direction 400 and temporarily stopped at a position where the second region 102 faces the second marking section 20 along the central axis 52 of the second focusing lens 22.

[0112] 8(b), the central axis 52 of the second condenser lens 22 is perpendicular to the surface of the second region 102. In this state, the second marking unit 20 performs marking on the second region 102.

[0113] In addition, it is preferable that the second manipulator 142 changes the orientation of the curved portion 110 so that the central axis 52 of the second focusing lens 22 is perpendicular to the surface of the second region 102 at approximately the center position of the second region 102 along the circumferential direction of the PET bottle 100.

[0114] <Function and effect of marking device 1b> As described above, in this embodiment, the second marking unit 20 performs marking in the second area 102 after the first marking unit 10 performs marking in the first area 101 and the manipulator 14 (variable portion) changes the orientation of the curved portion 110 (non-planar portion).

[0115] Thereby, the first condensing lens 12 can condense the first laser light L1 so that its central axis 51 is perpendicular to the surface of the first region 101, and the second condensing lens 22 can condense the second laser light L2 so that its central axis 52 is perpendicular to the surface of the second region 102. As a result, high-quality marking can be performed on both the first region 101 and the second region 102. Other effects are similar to those shown in the first embodiment.

[0116] [Fourth embodiment] Next, a marking device 1c according to a fourth embodiment will be described. <Example of the configuration of marking device 1c> Fig. 9 is a diagram showing an example of the configuration of a marking device 1c. As shown in Fig. 9, the marking device 1c has a first marking portion group 10c, a second marking portion group 20c, and a third marking portion group 30c.

[0117] The first marking part group 10c has three first marking parts 10 stacked in a stacking direction along the Y axis. The second marking part group 20c has three second marking parts 20 stacked in the stacking direction. The third marking part group 30c has three third marking parts 30 stacked in the stacking direction.

[0118] In this way, by stacking multiple marking units along the stacking direction along the cylindrical axis of the PET bottle 100, it is possible to perform marking in parallel over a wide range along the stacking direction of the PET bottle 100. This can further increase the productivity of the marking.

[0119] Also, the number of marking parts loaded can be changed for each marking part group. Fig. 10 is a diagram showing the configuration of a marking device 1c' as another example of the configuration of the marking device 1c. As shown in Fig. 10, the marking device 1c' has a first marking part group 10c', a second marking part group 20c', and a third marking part group 30c'.

[0120] The first marking portion group 10c' has three first marking portions 10 stacked in a direction along the Y axis. The second marking portion group 20c' has one second marking portion 20. The third marking portion group 30c' has two third marking portions 30 stacked in a direction along the Y axis.

[0121] The number of marking units that can be loaded may be limited due to restrictions on the installation location of the marking device 1c', but by changing the number of marking units that can be loaded for each marking unit group, it is possible to deal with restrictions on the installation location of the marking device 1c'. Note that other effects are similar to those shown in the first embodiment. The fourth embodiment can be combined with any of the first to third embodiments.

[0122] [Other Preferred Embodiments] In each of the above-described embodiments, a cylindrical PET bottle 100 is shown, but the medium on which the marking device according to each embodiment performs marking is not limited to a cylindrical object. For example, the marking device can also perform marking on a cylindrical member such as a PET bottle having a polygonal cross section.

[0123] Fig. 11 is a diagram showing an example of marking on a polygonal PET bottle 100a. Fig. 11 is a diagram showing the polygonal PET bottle 100a as viewed along the axial direction of the cylinder. As shown in Fig. 11, the side portion of the polygonal PET bottle 100a can be made into a first region 101a, a second region 102a, and a third region 103a.

[0124] The embodiment also includes a container. Fig. 12 is a diagram showing an example of a container according to the embodiment. As shown in Fig. 12, container 7 includes PET bottle 100, an object 9 contained inside PET bottle 100, and cap 8. A pattern 201 including the characters "label-less" is marked on the side of PET bottle 100. Note that cap 8 is not an essential component of container 7.

[0125] Although the embodiments have been described above, the present invention is not limited to the above specifically disclosed embodiments, and various modifications and adjustments are possible without departing from the scope of the claims.

[0126] The embodiment includes a marking method. For example, the marking method is a marking method using a marking device that performs marking on a non-flat portion of a medium, the non-flat portion having a plurality of regions including a first region and a second region, the marking method includes a step of performing the marking by converging a first light on the first region by a first optical system, and a step of performing the marking by converging a second light on the second region by a second optical system, and the second converging position by the second optical system is different from the first converging position by the first optical system in a direction along the central axis of the first optical system. With such a marking method, the same action and effect as the marking device according to the embodiment can be obtained.

[0127] In addition, all numbers such as ordinal numbers and quantities used in the description of the embodiments are merely examples for specifically explaining the technology of the present invention, and the present invention is not limited to the exemplified numbers. Furthermore, the connection relationships between the components are merely examples for specifically explaining the technology of the present invention, and the connection relationships for realizing the functions of the present invention are not limited to these.

[0128] Furthermore, each function of the above-described embodiments can be realized by one or more processing circuits. Here, the term "processing circuit" in this specification includes a processor programmed to execute each function by software, such as a processor implemented by an electronic circuit, and a device such as an ASIC (Application Specific Integrated Circuit), a DSP (digital signal processor), an FPGA (field programmable gate array), or a conventional circuit module designed to execute each function described above. [Explanation of symbols]

[0129] 1 Marking device 10 First Marking Section 11 First laser light source 11' Laser array (an example of multiple laser light sources) 12 First condenser lens (an example of the first optical system) 13 First Galvanometer Mirror 14 Manipulator 141 First manipulator (an example of a variable part) 142 Second manipulator (an example of a variable part) 20 Second Marking Section 21 Second laser light source 22 Second condenser lens (an example of the second optical system) 23 Second Galvanometer Mirror 30 3rd Marking Section 31 Third laser light source 32 Third condenser lens (an example of the third optical system) 33 3rd Galvanometer Mirror 40 Control section 41 Receiving section 42 Correction section 43 Marking control section 100 PET bottles (example of media) 101 First area 102 Second area 103 Third area 110 Curved surface (an example of a non-flat surface) 111 First marking plane (an example of the first focusing position) 112 Second marking plane (an example of the second focusing position) 113 3rd marking plane 120 Circumferential direction (example of curvature direction) 51 Central axis of the first focusing lens 52 Central axis of the second focusing lens 53 Central axis of the third focusing lens 7 Containment Unit 8 Cap 9. Items Detained 200 patterns 201 Patterns 300 Conveyor 400 Transport direction L1: First laser light (an example of the first light) L2 Second laser light (an example of the second light) L3 Third laser light (an example of the third light) d Distance W1, W2, W3 width h1, h2 maximum height difference [Prior art documents] [Patent documents]

[0130] [Patent Document 1] Patent No. 62784512

Claims

1. A marking device for marking a non-planar portion of a medium, comprising: The non-planar portion has a plurality of regions including a first region and a second region, a first marking unit that performs the marking by converging a first light onto the first area using a first optical system; a second marking unit that performs the marking by converging a second light onto the second area by a second optical system, a second focusing position by the second optical system is different from a first focusing position by the first optical system in a direction along a central axis of the first optical system, the non-planar portion has a curvature along a predetermined curvature direction; A marking device in which the greater the maximum height difference within each of the plurality of regions in a direction along the central axis of the first optical system, the smaller the width of each of the regions in the curvature direction.

2. The ink jet recording medium has a plurality of marking portions including the first marking portion and the second marking portion, The marking device according to claim 1 , wherein the light collecting positions of the plurality of marking portions are different in a direction along the central axis of the first optical system.

3. A marking device for marking a non-planar portion of a medium, comprising: The medium is transported in a predetermined transport direction, The non-planar portion has a plurality of regions including a first region and a second region, a first marking unit that performs the marking by converging a first light onto the first area using a first optical system; a second marking unit that performs the marking by converging a second light onto the second area using a second optical system; a variable portion provided between the first marking portion and the second marking portion along the conveying direction and configured to change an orientation of the non-flat portion; The second marking unit is a marking device in which the first marking unit performs the marking on the first region, and the variable unit changes the orientation of the non-planar portion and then performs the marking on the second region.

4. The marking device according to claim 1 , wherein the first region includes a non-overlapping region that is non-overlapping with the second region.

5. The marking device according to claim 1 , wherein the first marking section performs the marking in parallel with the second marking section.

6. The marking device according to claim 1 , wherein the first area overlaps with the second area.

7. A marking device for marking a non-planar portion of a medium, comprising: The non-planar portion has a plurality of regions including a first region and a second region, a first marking unit that performs the marking by converging a first light onto the first area using a first optical system; a second marking unit that performs the marking by converging a second light onto the second area using a second optical system; A control unit that controls each of the first marking unit and the second marking unit based on image data, a second focusing position by the second optical system is different from a first focusing position by the first optical system in a direction along a central axis of the first optical system, The control unit corrects the image data according to the shape of the non-planar portion.

8. The marking device according to claim 7 , wherein the control unit corrects the image data by enlarging or reducing an image represented by the image data.

9. The marking device according to claim 7 or 8, wherein the control unit corrects the image data so that the shading of the seam between the first region and the second region does not change or changes gradually.

10. the first marking unit raster-scans the first light along a longitudinal direction of the first region; The marking device according to claim 1 , wherein the second marking unit raster-scans the second light along a longitudinal direction of the second region.

11. The marking device according to any one of claims 1 to 10, wherein at least one of the first marking unit and the second marking unit has a plurality of laser light sources, and performs the marking by concentrating laser light emitted by each of the plurality of laser light sources.

12. a first marking unit group in which a plurality of the first marking units are loaded along a predetermined loading direction; The marking device according to claim 1 , further comprising: a second marking unit group in which a plurality of the second marking units are stacked along the stacking direction.

13. A marking method using a marking device for marking a non-planar portion of a medium, comprising the steps of: The non-planar portion has a plurality of regions including a first region and a second region, The marking device is performing the marking by converging a first light onto the first area using a first optical system; performing the marking by focusing a second light on the second area by a second optical system; a second focusing position by the second optical system is different from a first focusing position by the first optical system in a direction along a central axis of the first optical system, the non-planar portion has a curvature along a predetermined curvature direction; A marking method in which the greater the maximum height difference within each of the plurality of regions in a direction along the central axis of the first optical system, the smaller the width of each of the regions in the curvature direction.

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