Laser printing apparatus

Abstract

To improve user convenience of a laser printer.SOLUTION: The laser marking device L includes a correction mode selection unit 304d configured to select one of a plurality of correction modes in which the number of pattern regions Rp is different from each other, a storage unit 101 configured to store image information in the pattern region Rp set with respect to the captured image Pw and a relative positional relationship between the print pattern Pm and the pattern region Rp, a control unit 102 configured to control the coaxial camera 62 so that a new captured image Pw ' different from the captured image Pw is acquired before emitting the laser beam for printing, and a control unit 103 configured to specify a position and an attitude of the pattern region Rp in the new captured image Pw ' based on the new captured image Pw ' and the image information and based on the specified position and attitude and the relative positional relationship V1 and V2 stored in the storage unit 101. And a print data correction part 105 for calculating the correction amount of the position and attitude of the print pattern Pm and correcting the print data corresponding to the print pattern Pm.SELECTED DRAWING: Figure 13

Description

[Technical Field]

[0001] The present disclosure relates to a laser printing device. [Background technology]

[0002] For example, Patent Document 1 discloses a laser processing system equipped with a laser marker as a laser marking device. Specifically, the laser processing system disclosed in Patent Document 1 is equipped with a camera that captures an image of a shooting area that is smaller than the processing area consisting of an area that can be irradiated with laser light. This camera has an imaging optical axis (light receiving axis) branched from the laser optical axis (laser light emission axis), and captures an image of a designated shooting position within the processing area.

[0003] The laser processing system according to Patent Document 1 calculates errors in the position and posture of the workpiece (hereinafter also referred to as "workpiece errors") based on images captured within the processing area, and compensates for the calculated workpiece errors to form a processing pattern at a predetermined position on the workpiece. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-143785 Summary of the Invention [Problem to be solved by the invention]

[0005] The laser processing system disclosed in Patent Document 1 can obtain high resolution relative to the camera performance, but the narrower the shooting area, the more inconvenient it is in terms of ensuring the accuracy of calculation of workpiece errors and the correction amount of the processing pattern corresponding to those errors.

[0006] In response to this, it is possible to improve the calculation accuracy by calculating the correction amount using images taken at multiple shooting positions, but this is inconvenient in that since there are multiple shooting positions, it takes time to calculate each one.

[0007] Depending on the user's needs, the type of workpiece, etc., there may be cases where priority should be given to the accuracy of calculation of the correction amount, and cases where priority should be given to the time required to calculate the correction amount. In order to improve user convenience, it is advantageous to configure the system so that it can handle both calculation accuracy and calculation time in a balanced manner.

[0008] The present disclosure has been made in view of the above points, and has as its object to improve the user convenience of laser printing devices. [Means for solving the problem]

[0009] A first aspect of the present disclosure relates to a laser marking device. The laser marking device includes a laser beam generating unit that generates a laser beam to be irradiated onto a marking area of ​​a workpiece, a laser beam scanning unit that two-dimensionally scans the laser beam generated by the laser beam generating unit within the marking area, an imaging unit that has an imaging optical axis branched from the optical axis of the laser beam between the laser beam generating unit and the laser beam scanning unit and acquires an image by imaging at least a part of the marking area via the laser beam scanning unit, a display unit that displays a setting plane corresponding to the marking area and displays the image acquired by the imaging unit on the setting plane, a print setting unit that sets the position and posture of a print pattern to be printed on the workpiece on the setting plane displayed on the display unit, a print data generating unit that generates print data corresponding to the print pattern set by the print setting unit, a correction mode selecting unit that selects one correction mode from a plurality of correction modes each having a different number of correction areas for correcting the print data generated by the print data generating unit, and a correction mode selecting unit that selects a correction mode from a plurality of correction modes each having a different number of correction areas, and a correction mode selecting unit that selects a number of correction areas corresponding to the correction mode selected by the correction mode selecting unit on the display. a memory unit that stores, for a number of correction areas corresponding to the correction modes, mode identification information that identifies the correction mode selected by the correction mode selection unit, image information within the correction area set by the area setting unit, and a relative positional relationship between the print pattern and the correction area set by the print setting unit; a control unit that controls the imaging unit so that, before irradiating the laser light onto the print area, a new captured image different from the captured image is acquired after controlling the laser light scanning unit based on the mode identification information stored in the memory unit; a correction amount calculation unit that specifies a position and orientation of the correction area in the new captured image based on the new captured image obtained by the control unit and the image information stored in the memory unit, and calculates a correction amount for the position and orientation of the print pattern set by the print setting unit based on the specified position and orientation and the relative positional relationship stored in the memory unit; anda print data correction unit that corrects the print data generated by the print data generation unit and that corresponds to the print pattern for which the correction amount has been calculated.

[0010] According to the first aspect, the laser marking device can selectively use a plurality of correction modes each having a different number of correction areas, and can flexibly accommodate both cases where priority should be given to the accuracy of calculation of the correction amount and cases where priority should be given to the time required to calculate the correction amount, thereby improving user convenience.

[0011] Furthermore, according to a second aspect of the present disclosure, the laser printing device may be configured to estimate the time required to identify the position and orientation of the correction area based on the size of the correction area, and to include an estimation unit that displays the estimated time required on the display unit.

[0012] According to the second aspect, the laser printing device allows the user to visually confirm the estimated required time. The user can refer to the estimated time and proceed with various user inputs, such as selecting a correction mode, which is advantageous for improving user convenience.

[0013] Furthermore, according to a third aspect of the present disclosure, the storage unit stores the relative positional relationship between the print pattern set by the print setting unit and the correction area for each of the first and second correction areas as the correction area, and the imaging unit is controlled by the control unit together with the laser light scanning unit to acquire, as the new captured images, a first reference image related to the first correction area and a second reference image related to the second correction area, which is generated by imaging the same work as the first reference image, and the correction amount calculation unit calculates the correction amount in the first reference image. and a position and orientation of the first correction area in the second reference image, and calculates a correction amount for the position and orientation of the print pattern set by the print setting unit by combining the result of specifying the position and orientation of the first correction area and the result of specifying the position and orientation of the second correction area, and the control unit starts controlling the laser light scanning unit and the imaging unit to generate the second reference image while the correction amount calculation unit is specifying the position and orientation of the first correction area in the first reference image.

[0014] In general, an imaging unit that acquires an image via a laser beam scanning unit has superior resolution compared to an imaging unit that acquires an image without the intervention of a laser beam scanning unit. This contributes to improving the accuracy of the correction amount. On the other hand, such an imaging unit requires the driving of the laser beam scanning unit, which makes it disadvantageous for increasing the speed of the laser beam scanning unit. This may act in a disadvantageous direction in ensuring the calculation speed of the correction amount. An imaging unit that acquires an image via a laser beam scanning unit may reveal the advantages and disadvantages of using multiple correction regions.

[0015] In contrast, according to the third aspect, the control unit starts controlling the laser light scanning unit and the imaging unit to generate the second reference image while the correction amount calculation unit is identifying the position and orientation of the first correction area. This improves the calculation speed of the correction amount when considering the entire process related to the first correction area and the process related to the second correction amount area. This reduces the disadvantages of using multiple correction areas without compromising the advantages of using multiple correction areas.

[0016] Furthermore, according to a fourth aspect of the present disclosure, the memory unit may store an evaluation index of the relative positional relationship between the first correction area and the second correction area, and the correction amount calculation unit may determine the relative positional relationship between the first correction area and the second correction area in the new captured image, and evaluate the results of the correction amount calculation unit's identification of the positions and orientations of the first and second correction areas by comparing the determination result with the evaluation index.

[0017] According to the fourth aspect, by storing an evaluation index for the relative positional relationship between the first and second correction areas in the original captured image, it is possible to evaluate the results of identifying the position and orientation of each correction area when calculating the correction amount for a new captured image, which is advantageous for improving user convenience.

[0018] Furthermore, according to a fifth aspect of the present disclosure, the laser printing device may include a second imaging unit that captures an image having a wider field of view than the imaging unit by capturing an image of the workpiece without the intervention of the laser light scanning unit, and the control unit may select one of the imaging unit and the second imaging unit based on the size of the correction area, and acquire the new image by controlling the selected one of the imaging unit and the second imaging unit.

[0019] According to the fifth aspect, the laser marking device selectively uses the imaging unit according to the first aspect and a second imaging unit. The second imaging unit does not require control by a laser beam scanning unit, and is therefore advantageous in improving the speed at which correction amounts are calculated compared to the imaging unit. Providing options for the imaging unit is advantageous in improving user convenience. [Effects of the Invention]

[0020] As described above, according to the present disclosure, it is possible to improve the user convenience of a laser printing device. [Brief explanation of the drawings]

[0021] [Figure 1] FIG. 1 is a diagram illustrating an example of the overall configuration of a laser printing system. [Figure 2] FIG. 2 is a block diagram illustrating a schematic configuration of a laser printing device. [Figure 3] FIG. 3 is a block diagram illustrating the details of the setting device. [Figure 4] FIG. 4 is a diagram illustrating the schematic configuration of a print head. [Figure 5] FIG. 5 is a perspective view illustrating an example of the appearance of the print head. [Figure 6] FIG. 6 is a diagram illustrating the distance measurement unit and the triangulation method. [Figure 7] FIG. 7 is a flowchart showing the procedure for using the laser printing system. [Figure 8] FIG. 8 is a flowchart illustrating a procedure for creating print settings and search settings. [Figure 9] FIG. 9 is a diagram illustrating the relationship between the print area and the setting surface. [Figure 10] FIG. 10 is a diagram illustrating an example of the display content on the display unit. [Figure 11] FIG. 11 is a flowchart illustrating the details of the procedure for creating search settings. [Figure 12] FIG. 12 is a flowchart illustrating the details of the procedure for creating search settings. [Figure 13]FIG. 13 is a diagram for explaining a specific procedure for setting search conditions. [Figure 14] FIG. 14 is a diagram for explaining a specific procedure for setting search conditions. [Figure 15] FIG. 15 is a diagram illustrating a specific procedure for setting search conditions. [Figure 16] FIG. 16 is a diagram illustrating a specific procedure for setting search conditions. [Figure 17] FIG. 17 is a diagram illustrating a specific procedure for setting search conditions. [Figure 18] FIG. 18 is a diagram illustrating a specific procedure for setting search conditions. [Figure 19] FIG. 19 is a diagram illustrating a specific procedure for setting search conditions. [Figure 20] FIG. 20 is a diagram illustrating a specific procedure for setting search conditions. [Figure 21] FIG. 21 is a diagram illustrating a specific procedure for setting search conditions. [Figure 22] FIG. 22 is a flowchart illustrating an example of an operation procedure of the laser printing system. [Figure 23] FIG. 23 is a diagram showing a specific example of search settings. [Figure 24] FIG. 24 is a diagram for explaining XY deviation of a workpiece during operation. [Figure 25] FIG. 25 is a flowchart illustrating the second correction process. [Figure 26] FIG. 26 is a flowchart illustrating the second correction process. [Figure 27] FIG. 27 is a flowchart illustrating an example of the imaging process in the correction process. [Figure 28] FIG. 28 is a flowchart illustrating a process related to a pattern search. [Figure 29] FIG. 29 is a diagram illustrating how the first reference image is cut out. [Figure 30]FIG. 30 is a diagram for explaining a pattern search for the first correction region. [Figure 31] FIG. 31 is a diagram illustrating how the second reference image is cut out. [Figure 32] FIG. 32 is a flowchart illustrating the first correction process. [Figure 33] FIG. 33 is a diagram illustrating a print pattern after correction. DETAILED DESCRIPTION OF THE INVENTION

[0022] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. Note that the following description is for illustrative purposes only.

[0023] That is, although this specification describes a laser printing device, the present disclosure can be applied to laser application equipment in general, such as a "laser marker" or "laser processing device" that can perform printing using laser light (laser printing), regardless of the name "laser printing device."

[0024] Furthermore, in this specification, character markings will be described as a typical example of printing, but "printing" in this disclosure is not limited to character markings. Printing in this disclosure can also be applied to "markings other than characters," such as graphic markings.

[0025] Furthermore, "markings other than characters" includes not only markings of figures such as ":" and "x", but also two-dimensional code markings such as barcodes and QR Code (registered trademark). The term "figure" also includes any figure such as a symbol in addition to geometric figures such as "x". The characters and various figures to be marked are hereinafter collectively referred to as "printing patterns", to which the symbol "Pm" is attached.

[0026] In the following description, instead of the term "printing", this may be referred to as "laser printing", "marking", "printing processing" or "processing".

[0027] <1. Overall structure> Fig. 1 is a diagram illustrating the overall configuration of a laser printing system S, and Fig. 2 is a diagram illustrating the general configuration of a laser printing device L in the laser printing system S. Fig. 3 is a block diagram illustrating the details of a setting device 300. Fig. 4 is a diagram illustrating the general configuration of a print head 1.

[0028] As illustrated in FIG. 1, the laser printing system S includes a laser printing device L and an external device 400 connected to the laser printing device L.

[0029] Of these, the laser printing device L illustrated in Figures 1 and 2 is configured to print a predetermined printing pattern Pm within the printing area R1 by controlling the laser light generating unit 2 and the laser light scanning unit 4 described below.

[0030] The printing area R1 referred to here is an area set on the surface of the workpiece W as the printing target, as shown in FIG. 1, and corresponds to the setting surface R2 in the same figure. For example, in FIG. 1, the printing area R1 is configured as a rectangular area. The setting surface R2 referred to here corresponds to a virtual surface that can be displayed on the display unit 301 of the setting device 300. The setting surface R2 is used for various settings related to laser printing, as will be described later. The printing area R1 may be set to include the entire workpiece W, or may be set to include a portion of the workpiece W.

[0031] The laser printing device L prints by irradiating the workpiece W with laser light generated in its print head 1 and scanning the surface of the workpiece W in three dimensions. Note that "three-dimensional scanning" here refers to a concept that refers to a combination of a two-dimensional operation of scanning the irradiation position of the laser light on the surface of the workpiece W (so-called "two-dimensional scanning") and a one-dimensional operation of adjusting the focal position of the laser light. Note that three-dimensional scanning is not essential; the laser printing device L is sufficient as long as it is capable of at least two-dimensional scanning.

[0032] In particular, the laser marking device L according to this embodiment can emit laser light included in the ultraviolet (UV) wavelength range, for example, laser light having a wavelength around 355 nm, as laser light for marking on the workpiece W. In the following description, the laser light for marking on the workpiece W may be referred to as "UV laser light" or "printing laser light" to distinguish it from other laser light.

[0033] It should be noted that the laser light emitted by the laser marking device L is not limited to UV laser light. The laser marking device L may emit laser light within the near-infrared (NIR) wavelength range. When using laser light within the NIR wavelength range, the term "UV laser light" can be replaced with "NIR laser light."

[0034] As shown in FIGS. 1 and 2, the laser printing device L according to this embodiment includes a print head 1, a print controller 100, a connection cable 200, and a setting device 300.

[0035] The print head 1 can emit a printing laser beam toward the print area R1 by being controlled by the print controller 100. The print head 1 can perform three-dimensional scanning with the printing laser beam within the print area R1.

[0036] In addition, in order to realize various functions related to laser printing, the print head 1 is equipped with a distance measurement unit 5 that emits and receives distance measurement light, a guide light source 61 that emits guide light for projecting the print pattern Pm onto the workpiece W, a coaxial camera 62 that receives light for imaging (hereinafter referred to as "imaging light") and takes an image, and a wide-area camera 7 that receives the imaging light and takes an image separately from the coaxial camera 62 (see Figures 2 and 4).

[0037] 4, the print head 1 can perform two-dimensional scanning using not only the printing laser light, but also the guide light emitted from the guide light source 61, the distance measurement light emitted from the distance measurement unit 5 and reflected and received by the workpiece W, and the imaging light received by the coaxial camera 62 to generate the captured image Pw. As will be described later, this two-dimensional scanning is achieved by the control unit 102 operating the laser light scanning unit 4.

[0038] In other words, the optical axis of the printing laser light (laser optical axis A1) is made coaxial with the optical axis of the guide light emitted from the guide light source 61 (guide optical axis A2), the optical axis of the distance measurement light emitted from the distance measurement unit 5 and then reflected by and received by the workpiece W (distance measurement optical axis A3), and the optical axis of the visible light received by the coaxial camera 62 (imaging optical axis A4). Hereinafter, the coaxial optical axes may be collectively referred to as the "scanning axis Ax."

[0039] On the other hand, the optical axis of the visible light received by the wide area camera 7 (imaging optical axis A5) is not coaxial with the laser optical axis A1. Hereinafter, the imaging optical axis A4 related to the coaxial camera 62 may be referred to as the "first imaging optical axis A4," and the imaging optical axis A5 related to the wide area camera 7 may be referred to as the "second imaging optical axis A5."

[0040] The print controller 100 is configured as a controller for controlling the print head 1. In addition, the print controller 100 can store settings related to the print pattern Pm, such as various conditions (printing conditions) for printing the desired print pattern Pm, and can also correct those printing conditions. In this embodiment, the print controller 100 is separate from the print head 1.

[0041] The connection cable 200 electrically connects the print head 1 and the print controller 100. This connection cable 200 is configured, for example, by electrical wiring that can send and receive electrical signals between the print head 1 and the print controller 100.

[0042] When the excitation light generating unit 110 is laid out inside the print controller 100 as described below, the connection cable 200 may be configured by combining an optical fiber cable in addition to the electrical wiring.

[0043] More generally, one of the print head 1 and the print controller 100 can be incorporated into the other to form an integrated unit. In this case, unnecessary wiring can be omitted as appropriate.

[0044] The setting device 300 sets various printing conditions and functions as a terminal for displaying information related to laser printing to the user. The setting device 300 has, for example, a central processing unit (CPU) and memory, and is connected to the print controller 100 via wire or wirelessly so as to be able to send and receive electrical signals.

[0045] In this embodiment, the setting device 300 is configured by a personal computer such as a desktop computer or a laptop computer, but the present disclosure is not limited to such a configuration.

[0046] The setting device 300 may be configured by a dedicated terminal, such as a touch panel console, that can be connected to the laser printing device L. The setting device 300 may also be incorporated into the printing controller 100, for example, to be integrated.

[0047] The external device 400 is connected to the print controller 100 as needed. In the example shown in Fig. 1, the external device 400 is configured by a conveyance speed sensor 401 and a programmable logic controller (PLC) 402.

[0048] The conveying speed sensor 401 is configured by, for example, a rotary encoder, and can detect the conveying speed of the workpiece W. The conveying speed sensor 401 outputs a signal (detection signal) indicating the detection result to the print controller 100. Based on the detection signal input from the conveying speed sensor 401, the print controller 100 controls two-dimensional scanning of the printing laser light, etc.

[0049] The PLC 402 is configured by, for example, a microprocessor, and is capable of inputting a trigger signal to the print controller 100. The PLC 402 is used to control the laser printing system S in accordance with a predetermined sequence.

[0050] In addition to the above-mentioned devices and equipment, devices for operation and control, computers for performing various other processes, memory devices, peripheral devices, etc. can be connected to the laser printing device L wirelessly or via wires.

[0051] Below, we will explain in order the configuration related to the hardware configuration of the setting device 300, the print controller 100, and the print head 1, the configuration related to the data setting sent from the setting device 300 to the print controller 100, and the configuration related to the control of the print head 1 by the print controller 100 based on that data setting.

[0052] <2. Setting device 300> 1 and 2, the setting device 300 according to this embodiment includes a display unit 301, an operation unit 302, a storage unit 303, and a processing unit 304. The setting device 300 is a terminal operated by a user, and can also be called an "operation terminal."

[0053] (Display section 301) The display unit 301 displays information to the user. More specifically, the display unit 301 displays information to the user via its display screen. The display unit 301 can be configured with a liquid crystal display or an organic EL panel.

[0054] The display screen of the display unit 301 also functions as a screen for accepting user input (hereinafter referred to as "user input") via the operation unit 302. Specifically, the display unit 301 according to this embodiment displays a setting surface R2 corresponding to the print area R1. On this setting surface R2, an input interface Iu, such as a first interface I1 (described later), that accepts input of the print pattern Pm is arranged.

[0055] The input interface Iu is composed of a graphical user interface (GUI), such as a frame indicating the range of the setting surface R2, and a figure indicating the position and orientation of the print pattern Pm on the setting surface R2. The input interface Iu can accept input of the print pattern Pm based on user input, and can also display the contents of the accepted print pattern Pm on the setting surface R2.

[0056] It should be noted that it is not essential for the setting device 300 to be equipped with the display unit 301. The display unit 301 may be equipped in the print controller 100 or the print head 1. For example, if the setting device 300 is incorporated into the print controller 100 or a touch panel type console is used, a display screen provided on the print controller 100 or the console can serve as the display unit.

[0057] Furthermore, the display unit according to the present disclosure may be configured by a display separate from the setting device 300, the print controller 100, and the print head 1.

[0058] (Operation unit 302) The operation unit 302 receives the user input and inputs an electrical signal corresponding to the user input to the CPU, etc. The operation unit 302 can be configured with a keyboard and a pointing device. Pointing devices include a mouse, a joystick, etc.

[0059] It is not essential that the setting device 300 be equipped with the operation unit 302. The operation unit 302 may be equipped in the print controller 100 or the print head 1. For example, if the setting device 300 is incorporated into the print controller 100 or a touch panel type console is used, a switch, button, etc. provided on the print controller 100 or the console can be used as the scanning unit.

[0060] (Storage unit 303) The storage unit 303 stores various information. The storage unit 303 is composed of volatile memory such as random access memory (RAM) and read-only memory (ROM), and non-volatile memory such as a hard disk drive (HDD) and solid state drive (SSD). The storage unit 303 temporarily or continuously stores information that is input by the user via the operation unit 302, set in advance by the manufacturer, or transmitted and received each time to and from the print controller 100.

[0061] (Processing unit 304) The processing unit 304 executes various processes based on the contents stored in the storage unit 303. The processing unit 304 is configured by one or more processors (for example, CPUs).

[0062] The processing unit 304 executes processing corresponding to each function to realize each of a plurality of different functions. For example, the processing unit 304 can set the print pattern Pm to be printed on the workpiece W and the print conditions for printing the print pattern Pm based on user input. This function is realized, for example, by the print setting unit 304a of the processing unit 304.

[0063] The printing pattern Pm and printing conditions set by the processing unit 304 are stored in the memory unit 303 of the setting device 300, or are output to the printing controller 100 and stored in the memory unit 101 of the printing controller 100. Hereinafter, the combination of the printing pattern Pm and the printing conditions will be referred to as a "print setting." If necessary, the memory unit 303 of the setting device 300 may store the printing setting.

[0064] (Other components) 3, the processing unit 304 according to this embodiment also includes a print setting unit 304a, a print data generation unit 304b, a workflow generation unit 304c, a correction mode selection unit 304d, an area setting unit 304e, a GUI control unit 304f, a reception unit 304g, a camera selection unit 304h, and an estimation unit 304i. These elements execute various processes related to laser printing, as will be described in detail below. Furthermore, some or all of these elements may be configured in the print controller 100, rather than in the setting device 300.

[0065] <3. Print controller 100> 2, the print controller 100 includes a memory unit 101 that stores print settings transmitted from the setting device 300, a control unit 102 that controls the print head 1 based on the print settings, an excitation light generator 110 that generates laser excitation light (excitation light), and a trigger signal receiver 120. Note that it is not essential that the print controller 100 includes the excitation light generator 110; the print head 1 may also include the excitation light generator 110. Similarly, the trigger signal receiver 120 may be provided in the setting device 300.

[0066] (Storage unit 101) The storage unit 101 is configured to store the print settings determined by the setting device 300, and to output the stored contents to the control unit 102 as necessary.

[0067] Specifically, the storage unit 101 is composed of volatile memory such as RAM, ROM, etc., and non-volatile memory such as HDD, SSD, etc., and can temporarily or continuously store information indicating print settings. Note that if the setting device 300 is incorporated into the print controller 100, the storage unit 303 of the setting device 300 may also serve as the storage unit 101.

[0068] (control unit 102) The control unit 102 executes a printing process to form a predetermined printing pattern Pm within the printing area R1 by controlling the laser light generation unit 2 and the laser light scanning unit 4. In detail, the control unit 102 controls the excitation light generation unit 110, the laser light generation unit 2, the laser light scanning unit 4, etc. based on the printing settings stored in the storage unit 101. In conjunction with the printing process by the control unit 102, laser printing (printing operation) is performed by the print head 1.

[0069] Specifically, the control unit 102 has a CPU, memory, and input / output bus, and generates a control signal based on a signal indicating information input via the setting device 300 and a signal indicating printing conditions (details will be described later) read from the storage unit 101. The control unit 102 outputs the generated control signal to each part of the laser printing device L, thereby controlling laser printing on the workpiece W.

[0070] For example, when starting laser printing of the workpiece W, the control unit 102 reads the laser power stored in the memory unit 101, and outputs a control signal generated based on that laser power to the excitation light generating unit 110, thereby controlling the generation of laser excitation light.

[0071] Furthermore, when actually printing on the workpiece W, the control unit 102 reads the printing pattern Pm stored in the storage unit 101, for example, and outputs a control signal generated based on the printing pattern Pm to the laser light scanning unit 4, thereby two-dimensionally scanning the printing laser light. In this way, the control unit 102 can control the laser light scanning unit 4 to achieve two-dimensional scanning of the printing laser light.

[0072] (Excitation light generation unit 110) The excitation light generating unit 110 oscillates a laser beam according to a drive current, and collects the oscillated laser beam to output it as laser excitation light (excitation light). Specifically, the excitation light generating unit 110 according to this embodiment is configured with an excitation light source that oscillates a laser beam and a collecting unit that collects the laser. The excitation light source can be configured with, for example, a laser diode (LD). The collecting unit can be configured with, for example, a focusing lens.

[0073] The excitation light generated by the excitation light generation unit 110 is input to the laser light generation unit 2.

[0074] (Trigger signal receiving unit 120) The trigger signal receiving unit 120 receives an input of a trigger signal. This trigger signal functions as a trigger for causing the control unit 102 to execute a printing process. Specifically, the trigger signal receiving unit 120 according to this embodiment is electrically connected to the PLC 402, and receives a trigger signal output from the PLC 402. Upon receiving the trigger signal, the trigger signal receiving unit 120 inputs an electrical signal indicating this to the control unit 102. The control unit 102 receives the electrical signal and executes the printing process.

[0075] (Other components) 2, the print controller 100 according to this embodiment also includes a distance measurement unit 103, a correction amount calculation unit 104, and a print data correction unit 105. These elements execute various processes related to laser printing, as will be described in detail later. Furthermore, some or all of these elements may be configured in the setting device 300 instead of the print controller 100.

[0076] 1, the print controller 100 according to this embodiment has a first CPU 100a and a second CPU 100b as CPUs. The first CPU 100a executes processing related to the control unit 102, while the second CPU 100b executes processing related to the correction amount calculation unit 104. This configuration contributes to the realization of pipeline processing, which will be described later. The print controller 100 may have a multi-core CPU instead of or in addition to the first CPU 100a and second CPU 100b.

[0077] <4. Print head 1> Fig. 4 is a block diagram illustrating the schematic configuration of the print head 1 illustrated in Fig. 2 and the optical axis related to the distance measurement light. Fig. 5 is a perspective view illustrating the appearance of the print head 1. Fig. 6 is a diagram for explaining the distance measurement unit 5 and the triangulation method.

[0078] The print head 1 generates laser light (printing laser light) based on the excitation light, and irradiates the laser light onto the workpiece W. The laser light irradiated onto the workpiece W is scanned three-dimensionally as described above.

[0079] Specifically, the print head 1 includes a laser light generation unit 2, a height direction scanning unit 5, a laser light scanning unit 4, a print area inspection unit 6 having a coaxial camera 62, and a wide-area camera .

[0080] As shown in FIG. 4, the print head 1 has a housing 10 that incorporates a laser light generation unit 2, a height direction scanning unit 3 having a focus adjustment unit 33, a laser light scanning unit 4, a print area inspection unit 6 having a coaxial camera 62, and a wide-area camera 7.

[0081] As shown in Fig. 5, the lower surface of the housing 10 is defined by a plate-shaped bottom plate 10a. This bottom plate 10a is provided with an emission window 19 for emitting the printing laser light from the print head 1 to the outside of the print head 1. The emission window 19 is formed by fitting a plate-shaped transparent member that is capable of transmitting the printing laser light, guide light, and distance measurement light into a through-hole that passes through the bottom plate 10a in the plate thickness direction.

[0082] 5, the transparent member of the exit window 19 is configured to allow passage of both the scanning axis Ax scanned by the laser light scanning unit 4 and the second imaging optical axis Ax not scanned by the laser light scanning unit 4. As described above, the scanning axis Ax is formed by coaxially aligning the laser optical axis A1, the guide optical axis A2, the first imaging optical axis A4, and the distance measurement optical axis A3.

[0083] As shown in FIG. 4, the height direction scanning unit 3 and the focus adjusting unit 33 are interposed between the laser light generating unit 2 and the laser light scanning unit 4 in the propagation direction of the laser light.

[0084] In the following description, the longitudinal direction of the housing 10 in Fig. 5 may be simply referred to as the "longitudinal direction," "front-rear direction," or "X direction," and the lateral direction of the housing 10 in Fig. 5 may be simply referred to as the "lateral direction," "left-right direction," or "Y direction." Similarly, the height direction of the housing 10 in Fig. 5 may be simply referred to as the "height direction," "up-down direction," or "Z direction."

[0085] (Laser light generating unit 2) The laser light generation unit 2 generates a printing laser light to be irradiated onto the printing area R1 of the workpiece W. In detail, the laser light generation unit 2 generates a printing laser light based on the excitation light generated by the excitation light generation unit 110, and outputs the printing laser light to the outside of the laser light generation unit 2 (for example, to the height direction scanning unit 4).

[0086] Specifically, the laser light generation unit 2 has a laser oscillator 21, a beam sampler 22, and a power monitor 23. The laser oscillator 21 generates laser light having a predetermined wavelength based on excitation light, and converts and amplifies the wavelength to oscillate the printing laser light. The beam sampler 22 separates a portion of the printing laser light oscillated from the laser oscillator 21. The printing laser light separated by the beam sampler 22 is input to the power monitor 23.

[0087] The laser oscillator 21 has a laser medium 21a that generates a fundamental wave by performing stimulated emission corresponding to the excitation light, a nonlinear optical crystal 21b that generates printing laser light by modulating the fundamental wave, a Q switch (not shown) that pulses the fundamental wave emitted from the laser medium 21a, and a pair of reflecting mirrors (not shown) that resonate the laser light pulsed by the Q switch.

[0088] The nonlinear optical crystal 21b is not essential. For example, if an NIR laser is used as the printing laser, the nonlinear optical crystal 21b is not necessary. In that case, the fundamental wave is used as the printing laser light.

[0089] The laser medium 21a is a so-called solid-state laser crystal. For example, a rod-shaped Nd:YVO4 (yttrium vanadate) can be used as the solid-state laser crystal. This allows the laser oscillator 21 to emit laser light (NIR laser light) having a wavelength around 1064 nm as the fundamental wave. In this case, the fundamental wave can be generated by any method, such as a unidirectional excitation method using end pumping.

[0090] The nonlinear optical crystal 21b can be configured with multiple optical crystals, such as an optical crystal for generating a second harmonic wave and an optical crystal for generating a third harmonic wave. Various optical materials can be used for each optical crystal. The nonlinear optical crystal 21b is an optical element for increasing the wavelength of the fundamental wave, and functions as a so-called "wavelength conversion element."

[0091] For example, LBO (LiBO) can be used for the first wavelength conversion element that generates a second harmonic wave having a frequency twice that of the fundamental wave. Similarly, LBO (LiBO) can be used for the second wavelength conversion element that generates a third harmonic wave having a frequency three times that of the fundamental wave. However, this is not limiting. Various types of optical materials can be used, such as organic nonlinear optical materials and other inorganic nonlinear optical materials.

[0092] Additionally, the power monitor 23 detects the output of the printing laser light. The power monitor 23 is electrically connected to the printing controller 100, and can output the detection signal to the control unit 102 and the like.

[0093] The printing laser light generated by the laser light generation unit 2 reaches the laser light scanning unit 4 via the height direction scanning unit 3. The optical axis (laser optical axis A1) extending in the propagation direction of the printing laser light can be divided into two at the focus adjustment unit 33.

[0094] Hereinafter, the laser optical axis A1 connecting the laser light generation unit 2 and the focus adjustment unit 33 will be referred to as the upstream laser optical axis A11, and the laser optical axis A12 connecting the focus adjustment unit 33 and the laser light scanning unit 4 will be referred to as the downstream laser optical axis A12.

[0095] (Height direction scanning unit 3) As described above, the height direction scanning unit 3 is interposed between the laser light generation unit 2 and the laser light scanning unit 4. The height direction scanning unit 3 optically connects the laser light generation unit 2 to the laser light scanning unit 4, and also functions as a hub that optically connects the print area inspection unit 6 to the laser light scanning unit 4.

[0096] Specifically, the height direction scanning unit 3 according to this embodiment includes a first optical member 31, a second optical member 32, and the focus adjustment unit 33. As shown in Fig. 4, these elements are arranged in order from the top along the vertical direction.

[0097] The first optical member 31 is configured, for example, by a reflecting mirror that reflects the printing laser light. The first optical member 31 reflects the printing laser light emitted from the laser light generation unit 2 and guides it to the focus adjustment unit 33 by bending the upstream laser optical axis A11 downward.

[0098] The focus adjustment unit 33 adjusts the focal position of the printing laser light generated by the laser light generation unit. The printing laser light that has passed through the focus adjustment unit 33 is incident on the laser light scanning unit 4 via the second optical member 32.

[0099] Specifically, the focus adjustment unit 33 passes the printing laser light that is output from the laser light generation unit 2 and reflected by the first optical member 31, and adjusts the focus position of the printing laser light.

[0100] The focus adjustment unit 33 also emits the printing laser light that has passed through the focus adjustment unit 33 toward the second optical member 32. The printing laser light that has reached the second optical member 32 is guided to the laser light scanning unit 4 via the second optical member 32.

[0101] Although details are omitted, the focus adjustment unit 33 has, for example, an incident lens that transmits the printing laser light output from the laser light generation unit 2, a collimator lens that transmits the printing laser light that has passed through the incident lens, an exit lens that transmits the printing laser light that has passed through the incident lens and the collimator lens, and a lens drive unit that moves the incident lens.

[0102] When adjusting the focal position, for example, the lens driving unit is operated based on a control signal from the control unit 102. This operation changes the relative distance between the incident lens and the exit lens while keeping the optical axes of the incident lens, collimator lens, and exit lens coaxial with respect to the printing laser light. This change displaces the focal position of the printing laser light irradiated onto the workpiece W.

[0103] The focal position of the printing laser light is displaced so as to approach or move away from the emission window 19 of the print head 1. In other words, the focus adjustment unit 33 functions as a focus adjustment unit to scan the printing laser light in the vertical direction. Hereinafter, the scanning direction by the focus adjustment unit 33 may be referred to as the "Z direction."

[0104] The second optical member 32 is configured, for example, by a mirror that reflects the printing laser light. The second optical member 32 reflects the printing laser light emitted from the focus adjustment unit 33 and guides it to the laser light scanning unit 4 by bending the downstream laser optical axis A12 backward.

[0105] More specifically, the second optical member 32 according to this embodiment is configured with a dichroic mirror that reflects the printing laser light and transmits the guide light, distance measurement light, and imaging light. As a result, the second optical member 32 functions as a confluence portion that makes the downstream laser optical axis A12, guide optical axis A2, distance measurement optical axis A3, and first imaging optical axis A4 coaxial.

[0106] In other words, the guide optical axis A2, the distance measurement optical axis A3, and the first imaging optical axis A4 can be considered to branch off from the laser optical axis A1 between the laser light generation unit 2 and the laser light scanning unit 4.

[0107] (Printing area inspection unit 6) The print area inspection unit 6 has a guide light source 61 , a distance measurement unit 5 , a coaxial camera 62 , a first optical member 63 , and a second optical member 64 .

[0108] -Guide Light Source 61- The guide light source 61 emits a guide light toward the workpiece W. By emitting the guide light, the irradiation position of the printing laser light can be visually confirmed. Specifically, the guide light source 61 is configured to project the printing pattern Pm onto the workpiece W by the guide light. Therefore, the wavelength of the guide light is set to fall within the visible light range. As described above, the guide light source 61 has a guide light axis A2 branched from the laser light axis A1 between the laser light generation unit 2 and the laser light scanning unit 4.

[0109] As an example, the guide light source 61 according to this embodiment emits a red laser beam having a wavelength of about 655 nm as the guide light. The wavelength of the guide light is set to be different from the wavelengths of the printing laser beam, the distance measurement beam, and the imaging beam.

[0110] The guide light source 61 is coaxial with the printing laser light. More specifically, the guide light emitted from the guide light source 61 propagates along the guide light axis A2, which, as described above, branches off from the downstream laser light axis A12. Therefore, by appropriately operating the laser light scanning unit 4, the guide light can be two-dimensionally scanned within the printing region R1 illustrated in FIG. 9.

[0111] Furthermore, the guide light source 61 is electrically connected to the control unit 102, similar to the laser light generation unit 2 and the laser light scanning unit 4. The guide light source 61 emits guide light based on a control signal output from the control unit 102.

[0112] -First optical member 63- The first optical member 63 functions as a branching section that branches the guide optical axis A2 from the other optical axes A3, A4 among the guide optical axis A2, the ranging optical axis A3, and the first imaging optical axis A4. The first optical member 63 can be formed, for example, by a dichroic mirror that transmits the guide light and reflects the ranging light and the imaging light.

[0113] -Second optical member 64- The second optical member 64 functions as a branching section that branches the distance measurement optical axis A3 and the first imaging optical axis A4 from each other. The second optical member 64 can be formed, for example, by a dichroic mirror that passes one of the distance measurement light and the imaging light and reflects the other.

[0114] -Range measurement unit 5- The distance measuring unit 5 has an emitting section 51 that emits distance measuring light onto the surface of the workpiece W, and a light receiving section 52 that receives the distance measuring light reflected by the workpiece W.

[0115] 6 and 10, the emission section 51 of the distance measuring unit 5 emits distance measuring light via the laser light scanning section 4 toward a distance measuring position I indicating the position where the distance on the surface of the workpiece W is to be measured. The light receiving section of the distance measuring unit 5 receives the distance measuring light reflected at the distance measuring position I.

[0116] The light receiving section 52 of the distance measuring unit 5 is composed of, for example, light receiving elements, detects the light receiving position of each light receiving element at which the reflected light is received, and outputs a signal (detection signal) indicating the detection result. The detection signal output from each light receiving element is input to the print controller 100 and reaches the distance measuring section 103.

[0117] The laser marking device L can basically measure the distance to the surface of the workpiece W based on the light receiving position of the reflected light on the light receiving surface of the light receiving unit 52 (in this embodiment, the position of the peak of the spot). The so-called triangulation method is used as the distance measuring method.

[0118] That is, the distance measurement unit 103 measures the distance from the laser printing device L to the distance measurement position I by triangulation based on the light receiving position of the distance measurement light in the light receiving unit 52.

[0119] Specifically, the aforementioned memory unit 101 stores in advance the relationship between the light receiving position on the light receiving surface of the light receiving unit 52 and the distance from the print head 1 to the surface of the workpiece W. Meanwhile, the distance measurement unit 103 receives a signal indicating the light receiving position of the distance measuring light on the light receiving unit 52, more specifically, the peak position of the spot formed on the light receiving surface by the reflected light of the distance measuring light.

[0120] The distance measurement unit 103 measures the distance to the surface of the workpiece W based on the signal thus input and the relationship stored in the memory unit 101. The measurement value thus obtained is input to, for example, the control unit 101 and used by the control unit 101 to control the focus adjustment unit 33 and the like.

[0121] The measurement value obtained by the distance measurement unit 103 is used to determine the position and orientation of the workpiece W relative to the printing area R1 (for example, to determine whether the workpiece W is positioned in the correct position and orientation relative to the printing area R1).

[0122] For example, the laser printing device L automatically or manually determines the areas (printing points) on the surface of the workpiece W that are to be printed by the print head 1. Next, prior to executing the printing process, the laser printing device L measures the distance to each printing point (more precisely, distance measurement points set around the printing points) and determines the control parameters of the focus adjustment unit 33 so that the focal position corresponds to the measured distance. The laser printing device L operates the focus adjustment unit 33 based on the control parameters thus determined, and then performs printing on the workpiece W with the printing laser light.

[0123] -Coaxial Camera 62- The coaxial camera 62 captures an image Pw by capturing an image of the workpiece W. Specifically, the coaxial camera 62 has a first imaging optical axis A4 branching from the laser optical axis A1 between the laser light generation unit 2 and the laser light scanning unit 4, and captures an image of at least a portion of the printing area R1 via the laser light scanning unit 4. By capturing this image, the coaxial camera 62 captures an image Pw that includes at least a portion of the printing area R1. The coaxial camera 62 is an example of an "imaging unit" in this embodiment.

[0124] Although the coaxial camera 62 has a narrower field of view than the wide-area camera 7 described below, it can generate a coaxial image of the print area R1 enlarged at a relatively high magnification as the captured image Pw, or can perform two-dimensional scanning of the captured area via the laser light scanning unit 4. The coaxial camera 62 is used, for example, to locally enlarge and capture a portion of the print area R1. The captured image Pw generated (acquired) by the coaxial camera 62 can be displayed on the display unit 301 with at least a portion of it enlarged or reduced.

[0125] The coaxial camera 62 is coaxial with the printing laser light. More specifically, the reflected light (imaging light) used by the coaxial camera 62 for imaging propagates along the first imaging optical axis A4 and enters the coaxial camera 62, and as described above, the first imaging optical axis A4 branches off from the downstream laser optical axis A12. Therefore, by appropriately operating the laser light scanning unit 4, it is possible to two-dimensionally scan the printing area R1 illustrated in FIG. 9.

[0126] Furthermore, the coaxial camera 62 is electrically connected to the control unit 102, similar to the laser light generation unit 2 and the laser light scanning unit 4. The coaxial camera 62 generates a captured image Pw based on a control signal output from the control unit 102.

[0127] (Laser light scanning unit 4) The laser light scanning unit 4 performs two-dimensional scanning within the printing region R1 with the printing laser light generated by the laser light generating unit 2. Specifically, the laser light scanning unit 4 is configured to irradiate the workpiece W with the laser light (printing laser light) that has been emitted from the laser light generating unit 2 and passed through the focus adjusting unit 33, and to perform two-dimensional scanning on the surface of the workpiece W (particularly within the printing region R1).

[0128] More specifically, the laser light scanning unit 4 is configured by a so-called two-axis (X-axis and Y-axis) galvanometer scanner. That is, the laser light scanning unit 4 has a first scanner 41 for scanning the printing laser light incident from the focus adjustment unit 33 in a first direction, and a second scanner 42 for scanning the printing laser light scanned by the first scanner 41 in a second direction.

[0129] Here, the second direction refers to a direction that is approximately perpendicular to the first direction. Therefore, the second scanner 42 can scan the printing laser light in a direction that is approximately perpendicular to the first scanner 41.

[0130] In this embodiment, the first direction is equal to the front-to-rear direction (the longitudinal direction of the housing 10), and the second direction is equal to the left-to-right direction (the lateral direction of the housing 10). Hereinafter, the first direction will be referred to as the "X direction," and the second direction perpendicular to the first direction will be referred to as the "Y direction." Both the X direction and the Y direction are perpendicular to the Z direction described above.

[0131] The first scanner 41 and the second scanner 42 each have a mirror located at the tip thereof and a motor that rotates the mirror. Each mirror reflects the printing laser light. Each motor adjusts the rotational posture of the corresponding mirror. By adjusting the rotational posture of the mirror, it is possible to adjust the reflection angle of the printing laser light by each of the first scanner 41 and the second scanner 42. By adjusting the reflection angle of the printing laser light, it is possible to change the irradiation position of the printing laser light.

[0132] The laser beam scanning unit 4 deflects the printing laser beam toward the printing area R1 by operating the first scanner 41 and the second scanner 42 in accordance with a printing setting created in advance. The printing laser beam thus deflected passes through an exit window 19 provided in the housing of the print head 1 and is irradiated into the printing area R1. The desired printing pattern Pm can be printed in the printing area R1 by the printing laser beam.

[0133] As described above, not only the printing laser light but also the guide light and distance measurement light that have passed through the second optical member 32 of the height direction scanning unit 3 are incident on the laser light scanning unit 4. The laser light scanning unit 4 according to this embodiment can perform two-dimensional scanning of the guide light or distance measurement light that has thus entered by operating the first scanner 41 and the second scanner 42, respectively.

[0134] As also described above, the laser optical axis A1 of the printing laser light is also coaxial with the first imaging optical axis A4 of the coaxial camera 62. The laser light scanning unit 4 according to this embodiment can also perform two-dimensional scanning of the intersection of the first imaging optical axis A4 and the workpiece W, i.e., the imaging position by the coaxial camera 62, by operating the first scanner 41 and the second scanner 42, respectively.

[0135] (Wide-area camera 7) The wide-area camera 7 captures an image of the workpiece W without the intervention of the laser light scanning unit 4, thereby generating (acquiring) a captured image Pw having a wider field of view than the image generated by the coaxial camera 62. The wide-area camera 7 is an example of the "second imaging unit" in this embodiment.

[0136] It should be noted that the wide-area camera 7 is not essential in the present disclosure. In other words, various processes relating to pattern search, which will be described later, may be realized using only the coaxial camera 62 as an imaging unit.

[0137] The wide-area camera 7 is configured as imaging means that is not coaxial with the printing laser light. Although the wide-area camera 7 cannot perform two-dimensional scanning via the laser light scanning unit 4, it has a wider field of view than the coaxial camera 62 and can generate a wide-area image, as the captured image Pw, that captures the printing area R1 with a relatively wide field of view. The wide-area camera 7 is used, for example, to capture the entire printing area R1 at once.

[0138] The captured image Pw generated (acquired) by the wide area camera 7 can be displayed, with at least a portion thereof being enlarged or reduced, on the display unit 301. The display unit 301 can display the captured image Pw generated (acquired) by the wide area camera 7 and the captured image Pw generated (acquired) by the coaxial camera 62 side by side, or can alternatively display one of the two types of captured images Pw.

[0139] The wide-area camera 7 according to this embodiment is disposed directly above the exit window 19 and is fixed with its imaging lens facing downward. As described above, the second imaging optical axis A5 of the wide-area camera 7 is not coaxial with the optical axis A1 of the printing laser light (see FIGS. 4 and 9).

[0140] <5. How to use the laser marking system> Fig. 7 is a flowchart showing the procedure for using the laser printing system S. Fig. 8 is a flowchart illustrating the procedure for creating print settings and search settings. Fig. 9 is a diagram illustrating the relationship between the print area R1 and the setting surface R2. Fig. 10 is a diagram illustrating the display contents on the display unit 301. Figs. 11 and 12 are flowcharts illustrating the details of the procedure for creating search settings. Figs. 13 to 21 are diagrams for explaining the specific procedure for setting search conditions.

[0141] (Outline of usage) A laser marking system S equipped with a laser marking device L can be installed and operated on a conveying line, such as a factory production line, along which a plurality of workpieces W are conveyed in sequence. In operation, first, prior to starting operation of the conveying line, condition settings are created, such as the installation positions of the workpieces W that will flow along the conveying line, and the output of the printing laser light and distance measurement light to be irradiated onto the workpieces W (step S1 in FIG. 7).

[0142] The setting contents created in step S1 are stored in the print controller 100 after being created in advance, or are read by the print controller 100 immediately after being created (step S2 in FIG. 7).

[0143] When the conveyance line is in operation, the print controller 100 refers to the settings that have been stored in advance or that have been read immediately after they have been created. The laser marking device L operates based on the settings that have been referred to, and sequentially performs laser marking on each workpiece W supplied via the conveyance line (step S3 in FIG. 7).

[0144] (Specific steps for creating each setting) Fig. 8 illustrates a specific example of the processing in step S1 in Fig. 7. As illustrated in Fig. 8, in this embodiment, a control process related to print settings, a control process related to search settings, and a control process related to distance measurement settings are executed in sequence. Each control process is configured as an independent process without overlapping with each other.

[0145] First, in step S11, the coaxial camera 62 or the wide-area camera 7 built into the laser printing device L generates a captured image Pw including at least a part of the printing area R1. The captured image Pw generated by the coaxial camera 62 or the wide-area camera 7 is output to the setting device 300.

[0146] The display unit 301 of the setting device 300 displays a setting surface R2 associated with the print area R1, and also displays the captured image Pw on the setting surface R2 (see FIG. 10). The captured image Pw is displayed superimposed on the setting surface R2.

[0147] This allows the coordinate system (virtual coordinate system) defined on the setting surface R2 of the display unit 301 to correspond to the coordinate system (camera coordinate system) defined on the captured image Pw.

[0148] -Creating print settings- In the next step S12, the print setting unit 304a determines the print settings by reading out the contents stored in the memory unit 303 or the like, or by reading in user input via the operation unit 301, etc.

[0149] The print settings include a print pattern Pm that indicates the print content (marking shape) and print conditions that indicate various settings and conditions related to the print pattern Pm. The print conditions include at least settings related to the print block Pb.

[0150] In this embodiment, the print setting unit 304a shown in Figure 2 sets the position and orientation of the print pattern Pm to be printed on the workpiece W on the setting surface R2 displayed on the display unit 301. The position and orientation of the print pattern Pm can be set via the print block Pb. The term "orientation of the print pattern Pm" includes the rotation angle (θ) of the print pattern Pm on the XY plane.

[0151] The print block Pb can be used to adjust the layout (position), size, rotational attitude, etc. of the print pattern Pm. The print block Pb is also used in association with the distance measurement position I described above.

[0152] The display unit 301 can display the print pattern Pm and print blocks Pb superimposed on the captured image Pw. For example, in Fig. 10, a print pattern Pm consisting of the numbers "123" and rectangular print blocks Pb surrounding it are arranged on the setting surface R2 on the surface of the workpiece W. As shown in the figure, the display unit 301 displays the print pattern Pm and print blocks Pb arranged in this manner superimposed on the captured image Pw.

[0153] The shape of the print block Pb is not limited to the example shown in the figure. Any shape can be used as long as it indicates the position and size of the print pattern Pm. Furthermore, the terms "print pattern" and "print block" are merely introduced for convenience and are not intended to limit their use.

[0154] Although not shown in the figures, multiple workpieces W may be displayed on the setting surface R2, or only one workpiece W may be displayed as shown in Fig. 10. Multiple print blocks Pb may be arranged on one workpiece W, or one or multiple print blocks Pb may be arranged on some or all of multiple workpieces W.

[0155] 8, in this step, for example, the user manually creates a print block Pb and places the print block Pb on the setting surface R2. As described above, the setting surface R2 and the captured image Pw are associated with each other, so the user can place the print block Pb while visually checking the captured image Pw.

[0156] Once one or more print blocks Pb have been placed, the user determines a print pattern Pm for each print block Pb. The print pattern Pm is determined, for example, by the user operating operation unit 302, and the print setting unit 304a receives the operation input at that time via reception unit 304g.

[0157] The printing conditions constituting the printing settings may include conditions relating to the printing laser light (hereinafter referred to as "laser conditions") in addition to the settings relating to the printing block Pb.

[0158] The laser conditions include one or more of the irradiation position of the printing laser light, the target output (laser power) of the printing laser light, and the scanning speed (scan speed) of the printing laser light by the laser light scanning unit 4. As exemplified in the menu D1 displayed in the lower right of Fig. 10, these printing conditions (laser conditions) can be set for each print block Pb.

[0159] Alternatively, the laser conditions may be a combination of one or more of the Q-switch frequency, the defocus amount (spot variable value), and the scanning line spacing. Here, the defocus amount indicates the magnitude of deviation in the height direction between the focal position of the marking laser light and the surface of the workpiece W. By setting the defocus amount to a non-zero value, the spot diameter of the marking laser light can be changed. The number of printings indicates the number of times each line element is repeatedly scanned when the print pattern Pm is decomposed into multiple line elements. The scanning line spacing indicates the spacing between the scanning lines that make up each line element (particularly the spacing in the direction perpendicular to the scanning direction).

[0160] The laser conditions are determined, for example, by the user inputting numerical values ​​or the like into each item in menu D1 via operation unit 302, and the print setting unit 304a then accepts the input contents via acceptance unit 304g.

[0161] The print setting unit 304a reads the print blocks Pb arranged in this way, as well as the print patterns Pm and laser conditions determined for each print block Pb, and defines the combination of these as print settings.

[0162] In this embodiment, print data corresponding to the print pattern Pm, print block Pb, and laser conditions set by the print setting unit 304a is created by the print data generation unit 304b.

[0163] The print data according to this embodiment includes at least data relating to the position and orientation of the print pattern Pm, that is, data relating to the print block Pb.

[0164] Specifically, the print data includes at least the coordinates and rotation angle (coordinates and orientation in the print coordinate system) of the print block Pb on the setting surface R2, and is temporarily or continuously stored in the storage unit 303 or the like.

[0165] -Creating search settings- Generally, when the conveyor line is operated, each workpiece W that is sequentially laser-marked may have a positional deviation in the X and Y directions (XY directions). Furthermore, each workpiece W may also have a positional deviation (postural deviation) due to rotation on the XY plane. If a deviation occurs in the position and posture of the workpiece W, this will cause a deviation in the relative positional relationship between the workpiece W and the printing point of the printing laser light, which is inconvenient.

[0166] To address these problems, the laser marking device L according to this embodiment can correct deviations in the position and posture of the workpiece W by using various methods. Hereinafter, deviations in the position of the workpiece W in the XY directions and deviations in the posture of the workpiece W due to rotation on the XY plane will be collectively referred to as "XY deviations" to distinguish them from deviations in the Z direction, which will be described later. This XY deviation differs for each workpiece W transported on the transport line, and can also be referred to as errors in the position and posture of each workpiece W (workpiece errors).

[0167] The effect of XY misalignment on laser printing can be reduced or eliminated by correcting the position and orientation of the print pattern Pm for each workpiece W.

[0168] In other words, due to XY misalignment of the workpiece W, the print pattern Pm printed on the workpiece W will be misaligned in position and posture relative to the workpiece W. The laser printing device L according to this embodiment can correct the position of the print pattern in the XY directions and its posture on the XY plane (i.e., correct the print pattern related to the XY misalignment) to reduce or eliminate the latter misalignment.

[0169] As an example, in this embodiment, the position and orientation of the print pattern Pm are adjusted via the position and orientation of the print block Pb. The laser printing device L adjusts the print block Pb by correcting the print data, and through this adjustment, the aforementioned "correction of the print pattern Pm related to XY misalignment" can be performed. As a result, the relative position and orientation misalignment of the print pattern Pm with respect to the workpiece W, caused by the XY misalignment of the workpiece W, is corrected via the print block Pb corresponding to that print pattern Pb. Note that correction via the print block Pb is not essential.

[0170] Therefore, in step S13 following step S12, the area setting unit 304e of the setting device 300 creates condition settings (search settings) for correcting the print pattern related to the XY misalignment. The laser printing device L according to this embodiment is configured to use pattern search as a method for correcting the print pattern related to the XY misalignment.

[0171] To use the pattern search, the area setting unit 304e sets, as conditions (search conditions) for the pattern search, a pattern area Rp to be searched to identify the XY deviation of the workpiece W, and a search area Rs that defines the range in which the pattern area Rp is searched, on the captured image Pw. Note that the pattern area Rp is an area for correcting the print data by the print data correction unit 105, and is an example of a "correction area" in this embodiment.

[0172] It is not essential to set a part of the captured image Pw as the search region Rs (setting the search region Rs is not essential in the search conditions). Instead of setting the search region Rs, it is also possible to perform a pattern search on the entire captured image Pw. Even in such a configuration, by treating the entire captured image Pw as the search region Rs, it is possible to perform processing equivalent to that described below.

[0173] The laser printing device L according to this embodiment is configured so that the number of pattern areas Rp is not fixed but can be freely changed through dialogue with the user. Such a configuration will be described below with reference to Figures 11 to 12 and 13 to 21.

[0174] Below, an example will be given in which the number of pattern regions Rp as correction regions is one or two, but the present disclosure also includes a case in which the number of pattern regions Rp is three or more. In that case, the number of options for the number of pattern regions Rp (the number of correction modes) may be set to three or more. For example, a configuration may be provided in which a user input to select a "third correction mode," a "fourth correction mode," etc. can be accepted.

[0175] Fig. 11 illustrates the process performed in step S13 in Fig. 8. First, in step S201 in the figure, the correction mode selection unit 304d selects one correction mode from among a plurality of correction modes that differ from each other in the number of pattern regions Rp.

[0176] Specifically, when the control process proceeds to step S201, a first screen (first area) Sc1 exemplified in Fig. 13 is displayed on the display unit 301. The first screen Sc1 is, for example, a dialog superimposed on the setting screen R2 in Fig. 10.

[0177] Various GUIs are displayed as an input interface Ip on the display unit 301. Input and output relating to these GUIs are controlled by a GUI control unit 300f of the setting device 300.

[0178] For example, the first screen Sc1 displays first and second interfaces I1 and I2 that allow the user to select a correction mode. The first and second interfaces I1 and I2 are each configured as a GUI, and when an operation to select one of them is performed using the operation unit 302 (for example, by operating a mouse), an electrical signal corresponding to the operation is input to the correction mode selection unit 304d via the reception unit 304g. The correction mode selection unit 304d performs various processes, such as various settings, based on the input electrical signal.

[0179] When a click operation or the like is performed on the first interface I1, the correction mode selection unit 304d selects the first correction mode. In the first correction mode, the number of pattern regions Rp is one. When a click operation or the like is performed on the second interface I2, the correction mode selection unit 304d selects the second correction mode. In the second correction mode, the number of pattern regions Rp is two. The first correction mode and the second correction mode are configured to be alternatively selected.

[0180] In the following step S202, for example, the processing unit 304 selects the print block Pb to be corrected, or more precisely, the print block Pb to be corrected for the print pattern Pm related to the XY misalignment. The print block Pb to be corrected for the print pattern Pm related to the XY misalignment is the print block Pb corresponding to the print data correction candidate by the print data correction unit 105. Note that step S202 may be performed before step S201 is executed.

[0181] Specifically, when the control process proceeds to step S202, a first screen (first area) Sc1 exemplified in Fig. 13 is displayed on the display unit 301. The first screen Sc1 is, for example, a dialog superimposed on the setting screen R2 in Fig. 10.

[0182] In addition to the first and second interfaces I1 and I2, the first screen Sc1 also displays third to fifth interfaces I3 to I5 that allow the user to select a print block Pb. These user interfaces are all configured as GUIs. When these user interfaces are operated by the operation unit 302 (for example, by operating a mouse), an electrical signal corresponding to the operation is input to the processing unit 304 via the reception unit 304g. The processing unit 304 executes various processes, such as various settings, based on the input electrical signal.

[0183] The third interface I3 and the fourth interface I4 are designed to be alternatively selectable. When a click operation or the like is performed on the third interface I3, the processing unit 304 selects all print blocks Pb as the correction targets. "All print blocks Pb" here refers to all print blocks Pb (one in the illustrated example) that have been set in advance by the user, as in the block list D2 in FIG. 10.

[0184] On the other hand, when a click operation or the like is performed on the fourth interface I4, the processing unit 304 selects one or more print blocks Pb specified by the user. When the fifth interface I5 is clicked, one or more print blocks Pb can be specified based on user input from the block list D2 in Figure 10. The processing unit 304 selects the print blocks Pb thus specified as the targets for correction of the print pattern related to XY misalignment.

[0185] In the subsequent steps S203 to S209, the region setting unit 304e sets, in the captured image Pw displayed on the display unit 301, pattern regions Rp of the number corresponding to the correction mode selected by the correction mode selection unit 304d.

[0186] Hereinafter, the pattern region Rp and search region Rs corresponding to the first correction mode will be referred to as the first pattern region Rp1 and the first search region Rs1, respectively. Similarly, the pattern region Rp and search region Rs corresponding to the second correction mode will be referred to as the second pattern region Rp2 and the second search region Rs2, respectively.

[0187] Here, the first pattern region Rp1 is an example of a "first correction region," and the second pattern region Rp2 is an example of a "second correction region."

[0188] More specifically, the region setting unit 304e sets a first pattern region Rp1 and a first search region Rs1 in the captured image Pw displayed on the display unit 301 from step S203 to step S206.

[0189] More specifically, in step S203, the region setting unit 304e sets the first pattern region Rp1, and in step S204, the region setting unit 304e sets the first search region Rs1. Note that step S204 and the setting order of step S204 are not limited to the flow of Fig. 11. It is sufficient that the first search region Rs1 is larger in size than the first pattern region Rp1.

[0190] Specifically, when the control process proceeds to step S203, a second screen (second area) Sc2, as shown in Fig. 14, is displayed on the display unit 301. The second screen Sc2 is, for example, a dialog box superimposed on the setting screen R2 in Fig. 10. The interfaces displayed on the second screen Sc2, such as the eighth interface I8, are all configured as GUIs that accept mouse operations.

[0191] When these user interfaces are operated (for example, by using a mouse) using the operation unit 302, an electrical signal corresponding to the operation is input to the region setting unit 304e via the reception unit 304g. The region setting unit 304e executes various processes, such as various settings, based on the input electrical signal.

[0192] The second screen Sc2 displays eighth and ninth interfaces I8 and I9 that allow the user to set the first pattern region Rp1. The former, eighth interface I8, is a user interface for setting the first pattern region Rp1 by operating the mouse. The latter, ninth interface I9, is a user interface for setting the first pattern region Rp1 by specifying coordinates.

[0193] In the example shown in Fig. 15, a first pattern area Rp1 corresponding to each print block Pb is set by performing a mouse operation or the like on the captured image Pw. Note that, in the example shown in Fig. 15, the pattern area Rp1 is set so as to surround the print pattern Pm, but this setting is not limited thereto. The relative positional relationship between the print pattern Pm and the pattern area Rp is not particularly limited.

[0194] The second screen Sc2 displays tenth and eleventh interfaces I10 and I11 that allow the user to set the first search region Rs1. The former tenth interface I10 is a user interface for setting the first search region Rs1 by operating the mouse. The latter eleventh interface I11 is a user interface for setting the first search region Rs1 by specifying coordinates.

[0195] The second screen Sc2 further displays a twelfth interface I12 that allows the user to set a first search region Rs1. By entering a numerical value in the input field (search range) of the twelfth interface I12, the first pattern region Rp1 is expanded horizontally and vertically by the amount of the entered numerical value, and the expanded region is set as the first search region Rs1. In the example shown in FIG. 16, the first search region Rs1 corresponding to each print block Pb is set by performing a mouse operation or the like on the captured image Pw.

[0196] The second screen Sc2 also displays a thirteenth interface I13 that allows the user to set a search range for posture deviation. By entering a numerical value in the input field (search angle) of the thirteenth interface I13, the search range for posture deviation in XY deviation (for example, the ±angle range to search) can be determined by the entered numerical value.

[0197] In the following step S205, the camera selection unit 304h selects one of the coaxial camera 62 and the wide-area camera 7 based on the size of the first pattern region Rp1 as the correction region.

[0198] Specifically, the camera selection unit 304h compares the size of the first search area Rs1 set based on the first pattern area Rp1 with the field of view size of the coaxial camera 62, and determines whether the size of the first search area Rs1 is smaller than the field of view size.

[0199] If the determination is YES, the camera selection unit 304h selects the coaxial camera 62. In this case, the control unit 102 of the print controller 100 uses the coaxial camera 62 when performing a pattern search for the first pattern region Rp1.

[0200] On the other hand, if the determination is NO, the camera selection unit 304h selects the wide area camera 7. In this case, the control unit 102 of the print controller 100 will use the wide area camera 7 when performing a pattern search for the first pattern region Rp1.

[0201] 14 further displays first information If1 that allows the user to visually confirm the selection result. By operating a fifteenth interface I15 located nearby, a GUI can be displayed on the display unit 301 for manually selecting one of the coaxial camera 62 and the wide-area camera 7, and for manually adjusting the imaging magnification, brightness, etc. of each imaging unit.

[0202] Returning to FIG. 11, in step S206, the region setting unit 304e determines whether or not the setting of the pattern regions Rp in the number corresponding to the correction mode selected by the correction mode selection unit 304d has been completed.

[0203] Specifically, in step S206, the region setting unit 304e determines whether the second correction mode is selected. If the determination is YES, the region setting unit 304e advances the control process to step S207. If the determination is NO in step S206, the region setting unit 304e advances the control process to step S210 in FIG. 12.

[0204] From step S207 to step S209, the region setting unit 304e sets a second pattern region Rp2 and a second search region Rs2 in the captured image Pw displayed on the display unit 301. The region setting unit 304e executes step S207, step S208, and step S209 in that order.

[0205] In step S207, the region setting unit 304e sets the second pattern region Rp2, and in step S208, the region setting unit 304e sets the second search region Rs2. Note that the setting order of steps S207 and S208 is not limited to the flow in Fig. 11. It is sufficient that the second search region Rs2 is larger in size than the second pattern region Rp2.

[0206] The processing performed in steps S207 and S208 is essentially the same as the processing performed in steps S203 and S204, except for whether the processing relates to the first pattern area Rp1 and the first search area Rs1 or the second pattern area Rp2 and the second search area Rs2, and for some of the display aspects of the third screen (third area) Sc3 shown below.

[0207] Specifically, when the control process proceeds to step S207, a third screen (third area) Sc3 exemplified in Fig. 17 is displayed on the display unit 301. The third screen Sc3 is, for example, a dialog superimposed on the setting screen R2 of Fig. 10.

[0208] In the third screen Sc3, user interfaces that perform substantially the same functions as the user interfaces displayed on the second screen Sc2, such as the eighth interface I8, are given the same symbols as the respective user interfaces displayed on the second screen Sc2.

[0209] As shown in a comparison between Figures 14 and 17, the third screen Sc3 is displayed in a different color from the second screen Sc2. This allows the user to make settings for the first search region Rs1 and the second search region Rs2 without confusing them. As a result, user convenience can be improved.

[0210] 18, when a mouse operation or the like is performed on the same captured image Pw as that used to set the first pattern area Rp1, the user input is input to the area setting unit 304e via the receiving unit 304g. The area setting unit 304e sets a second pattern area Rp2 and a second search area Rs2 corresponding to each print block Pb based on the user input.

[0211] In the following step S209, the camera selection unit 304h selects one of the coaxial camera 62 and the wide-area camera 7 based on the size of the second pattern region Rp2 as the correction region.

[0212] Specifically, the camera selection unit 304h compares the size of the second search area Rs2 set based on the second pattern area Rp2 with the field of view size of the coaxial camera 62, and determines whether the size of the second search area Rs2 is less than or equal to the field of view size.

[0213] If the determination is YES, the camera selection unit 304h selects the coaxial camera 62. In this case, the control unit 102 of the print controller 100 will use the coaxial camera 62 when performing a pattern search for the second pattern region Rp2.

[0214] On the other hand, if the determination is NO, the camera selection unit 304h selects the wide area camera 7. In this case, the control unit 102 of the print controller 100 will use the wide area camera 7 when performing a pattern search for the second pattern area Rp2.

[0215] As a modified example, the camera selection unit 304h may determine whether the accuracy of the pattern search using the captured image Pw generated by the wide area camera 7 satisfies a predetermined standard based on the size of the first pattern region Rp1 and the resolution of the wide area camera 7. The camera selection unit 304 may further select the wide area camera 7 if the predetermined standard is satisfied based on the determination result, or may select the coaxial camera 62 if the standard (predetermined standard) is not satisfied.

[0216] In the modified example, the wide-area camera 7 can be selected with priority, which improves convenience for users who want to prioritize takt time over detection accuracy. In any case, the camera selection unit 304h is configured to be able to select a camera (the coaxial camera 62 and the wide-area camera 7) with more appropriate detection performance according to the size of the set area.

[0217] 12, the setting device 300 operates the distance measuring unit 5 via the distance measurement section 103 to measure the distance to a predetermined position on the workpiece W and within the first pattern area Rp1. This measurement is performed, for example, for a plurality of predetermined positions.

[0218] The setting device 300 receives the measurement results of the distance measurement unit 103 and associates the pixel size on the captured image Pw with the actual size within the printing area R1. This makes it possible to associate the coordinate system (actual coordinate system) indicating the irradiation position of the printing laser light with the camera coordinate system. This association makes it possible to associate the control parameters of the laser light scanning unit 4 (the rotation angles of the first and second scanners 41, 42) with the size of the first pattern area Rp1, etc. on the setting surface R2.

[0219] In the following step S211, the region setting unit 304e selects the imaging unit set in step S205 from the coaxial camera 62 and the wide-area camera 7. The region setting unit 304e captures an image of the first pattern region Rp1 by controlling the selected imaging unit via the control unit 102. The region setting unit 304e sets the captured image thus captured as the first pattern image Pp1 as image information.

[0220] Specifically, when the control process proceeds to step S211, a fourth screen (fourth area) Sc4, exemplified in Fig. 19, is displayed on the display unit 301. The fourth screen Sc4 is, for example, a dialog superimposed on the setting screen R2 of Fig. 10. The interfaces displayed on the fourth screen Sc4, such as the seventeenth interface I17, are all configured as GUIs that accept mouse operations.

[0221] When these user interfaces are operated (for example, by using a mouse) using the operation unit 302, an electrical signal corresponding to the operation is input to the region setting unit 304e via the reception unit 304g. The region setting unit 304e executes various processes, such as various settings, based on the input electrical signal.

[0222] The second screen Sc2 displays the first pattern image Pp1 for the user to confirm. On the right side of the first pattern image Pp1, second information If2 indicating the type of camera (coaxial camera 62 or wide-area camera 7) used to capture the first pattern image Pp1 and a seventeenth interface I17 that allows the user to set a mask area are displayed.

[0223] The mask area is an area for masking information that may differ for each workpiece W, such as a pattern (e.g., a serial number) that has been pre-processed on each workpiece W. Such information is inconvenient for pattern search, but by masking it, a more accurate pattern search can be achieved.

[0224] Furthermore, third information If3 indicating the estimation result of the first predicted time is further displayed on the right side of the first pattern image Pp1. The first predicted time (third information If3) is the time required to identify the position and orientation of the first pattern region Rp1. The first predicted time is estimated by the estimation unit 304i of the setting device 300.

[0225] Specifically, the estimation unit 304i estimates the first predicted time based on the size of the first pattern region Rp1. More specifically, the estimation unit 304i estimates the first predicted time to be longer as the size of the first pattern region Rp1 increases.

[0226] Further, below the first pattern image Pp1, there are an eighteenth interface I18 that can input the lower limit of the correlation value, and a nineteenth interface I19 that can input the imaging delay.

[0227] The correlation value is a parameter that serves as an index in a pattern search. For example, if the correlation value obtained during an actual pattern search is equal to or higher than the lower limit, it can be determined that the pattern search was successful (a region identical to the first pattern region Rp1 was found). On the other hand, if the correlation value obtained during the pattern search is less than the lower limit, it can be determined that the pattern search was unsuccessful (a region identical to the first pattern region Rp1 was not found).

[0228] The imaging delay indicates the waiting time from when the workpiece W to be printed is transported (for example, from when the trigger signal receiving unit 120 receives the trigger signal) until the imaging required for pattern search begins when the laser printing system S is in operation.

[0229] Additionally, below the 19th interface I19, a 20th interface I20 for selecting a print pattern correction item related to XY misalignment is displayed. When the 20th interface I20 accepts a user input, a sixth screen (sixth area) Sc6, exemplified in FIG. 21, is displayed on the display unit 301.

[0230] On the sixth screen Sc6, from the top to the bottom, the twenty-fifth interface I25, the twenty-sixth interface I26, the twenty-seventh interface I27, and the twenty-eighth interface I28 are displayed. The twenty-eighth interface I28 has the same function as the thirteenth interface I13 in FIG. 14.

[0231] The 25th interface I25 is, for example, a check box, and can select whether or not to correct the positional deviation in the X direction among the corrections of the print pattern related to the XY deviation based on the user's input.

[0232] The 26th interface I26 is, for example, a check box, and can select whether or not to correct the positional deviation in the Y direction among the corrections of the print pattern related to the XY deviation based on the user's input.

[0233] The 27th interface I27 is, for example, a check box, and based on user input, it is possible to select whether or not to correct the posture deviation on the XY plane among the corrections of the print pattern related to the XY deviation.

[0234] Returning to Figure 19, below interface 20 I20, interface 21 I21 is displayed for selecting the print block Pb to be corrected. Clicking interface 21 I21 allows the user to specify one or more print blocks Pb from block list D2 in Figure 10 based on user input. The processing unit 304 determines the print block Pb thus specified as the target for correction of XY misalignment.

[0235] Also, below the 21st interface I21, a 22nd interface I22, a 23rd interface I23, and a 24th interface I24 are displayed for setting NG conditions in the pattern search and the processing to be performed when the NG conditions are met.

[0236] The 22nd interface I22 is, for example, a user interface for selecting one of a plurality of NG conditions. When the 22nd interface I22 is operated, a plurality of pre-set NG conditions are displayed. The 22nd interface I22 accepts user input to select one NG condition. The plurality of NG conditions include a failure in the pattern search (search failure) and a success in the pattern search (search success).

[0237] The latter NG condition helps to discover pattern areas Rp that should not be included in the workpiece W. This is effective in discovering processing that should not be performed at the stage of transport to the laser printing device L, such as double printing.

[0238] The 23rd interface I23 is a user interface for selecting an action to be taken when the NG condition set via the 22nd interface I22 is met, for example. When the 23rd interface I23 is operated, multiple pre-set actions are displayed. The 23rd interface I23 accepts user input to select one action. The multiple actions include not outputting either an error or a warning (not outputting an error or warning), outputting a warning (outputting a warning), and outputting an error and halting laser printing (outputting an error).

[0239] The 24th interface I24 is a user interface for selecting an action to be taken when the NG condition set via the 22nd interface I22 is met, for example. When the 24th interface I24 is operated, multiple pre-set actions are displayed. The 24th interface I24 accepts user input to select one action. The multiple actions include continuing laser printing (continue printing) and interrupting laser printing (interrupt printing). In this embodiment, when "output error" is selected via the 23rd interface I23, "interrupt printing" is automatically selected.

[0240] Returning to FIG. 12, in the following step S212, the area setting unit 304e determines whether or not the setting of the pattern areas Rp in the number corresponding to the correction mode selected by the correction mode selection unit 304d has been completed.

[0241] Specifically, in step S212, the region setting unit 304e determines whether the second correction mode is selected. If the determination is YES, the region setting unit 304e advances the control process to step S213. If the determination is NO in step S212, the region setting unit 304e ends the control process illustrated in FIG. 12.

[0242] In step S213, the setting device 300 operates the distance measuring unit 5 via the distance measurement section 103 to measure the distance to a predetermined position on the workpiece W and within the second pattern region Rp2. This measurement is performed, for example, for a plurality of predetermined positions.

[0243] In the following step S214, the region setting unit 304e selects the imaging unit set in step S209 from the coaxial camera 62 and the wide-area camera 7, and captures an image of the second pattern region Rp2 using the selected imaging unit. The region setting unit 304e sets the captured image as the second pattern image Pp2 as image information.

[0244] The processing performed in steps S213 and S214 is substantially the same as the processing performed in steps S213 and S214, except for whether the processing is related to the first pattern image Pp1 or the second pattern image Pp2, and for some of the display aspects of the fifth screen (fifth area) Sc5 shown below.

[0245] Specifically, when the control process proceeds to step S213, a fifth screen (fifth area) Sc5 illustrated in Fig. 20 is displayed on the display unit 301. The fifth screen Sc5 is, for example, a dialog superimposed on the setting screen R2 in Fig. 10.

[0246] In the fifth screen Sc5, user interfaces that perform substantially the same functions as the user interfaces displayed on the fourth screen Sc4, such as the seventeenth interface I17, are given the same symbols as the respective user interfaces displayed on the fourth screen Sc4.

[0247] 19 and 20, the area of ​​the fifth screen Sc5 including the second pattern image Pp2 is displayed in a color different from that of the fourth screen Sc4. This allows the user to make settings related to the first pattern image Pp1 and the second pattern image Pp2 without confusing them. As a result, user convenience can be improved.

[0248] As shown in FIG. 20, the fifth screen Sc5 displays the second pattern image Pp2 and various user interfaces for making settings related to the second pattern image Pp2.

[0249] 19 is that, for example, the second information If2 in Fig. 20 indicates the type of camera (coaxial camera 62 or wide-area camera 7) used to capture the second pattern image Pp2. The seventeenth interface I17 in Fig. 20 is a user interface for setting a mask area to be used in a pattern search related to the second pattern image Pp2, rather than in a pattern search related to the first pattern image Pp1.

[0250] 20 indicates the estimation result of the second predicted time. The second predicted time (third information If3) is the time required to identify the position and orientation of the second pattern region Rp2. The second predicted time is estimated by the estimation unit 304i.

[0251] 12, in step S215 following step S214, the storage unit 101 stores at least three types of information. This process is executed for the number of pattern areas Rp corresponding to the correction mode. That is, the storage unit 101 stores one set of information when the first correction mode is selected, and stores two sets of information when the second correction mode is selected.

[0252] The set of the three types of information described above stored by storage unit 101 need only associate the three types of information with each pattern area Rp, and does not have to have a one-to-one correspondence with the pattern area Rp. For example, the mode identification information associated with the first pattern area Rp1 and the second pattern area Rp2 set when the second correction mode is selected may be a single common mode identification information, or if there are multiple print blocks Pb to be corrected, multiple pieces of information indicating the relative positional relationship between the print pattern Pm and the pattern area Rp may be stored as mode identification information, each associated with each pattern area Rp.

[0253] Here, the three types of information stored in the storage unit 101 are configured by a combination of mode identification information, image information, and position information.

[0254] The mode identification information is information for identifying the correction mode selected by the correction mode selection unit 304d. For example, the mode identification information may be a flag indicating that the first or second correction mode is selected.

[0255] As described above, the image information is the pattern image Pp in the pattern area Pp set by the area setting unit 304e. When the first correction mode is selected, the image information is composed of only the first pattern image Pp1, and when the second correction mode is selected, the image information is composed of both the first and second pattern images Pp1 and Pp2.

[0256] The image information stored in the storage unit 101 may be image features included in the pattern image Pp. The image features include, for example, shape information such as brightness edges and object contours, color information, and texture information.

[0257] The position information is information that indicates the relative positional relationship between the print pattern Pm and the pattern area Rp set by the print setting unit 304a. As shown in Figures 23 and 33, which will be described later, in this embodiment, instead of the print pattern Pm, the relative positional relationships V1 and V2 between the print block Pb and the pattern area Rp, which indicate its position and orientation, are used.

[0258] In other words, the "relative positional relationship" referred to here includes not only the positional misalignment in the XY direction, but also the relative posture relationship between the print block Pb and the pattern area Rp due to rotation on the XY plane.

[0259] When the first correction mode is selected, the position information is composed only of the relative positional relationship V1 between the print block Pb and the first pattern region Rp1. The first correction mode corresponds to a so-called "one-point correction."

[0260] On the other hand, when the second correction mode is selected, the position information is composed of the relative positional relationship V1 between the print block Pb and the first pattern region Rp1 and the relative positional relationship V2 between the same print block Pb and the second pattern region Rp2. In this case, the print block Pb with which the relative positional relationship is formed is common to the first pattern region Rp1 and the second pattern region Rp2. The second correction mode corresponds to a so-called "two-point correction."

[0261] That is, in the second correction mode, the print pattern Pm to be corrected is corrected based on both the relative positional relationship between the print block Pb corresponding to that print pattern Pm and the first pattern region Rp1 (see V1 in FIG. 23), and the relative positional relationship between the same print block Pb and the second pattern region Rp2 (see V2 in FIG. 23). This makes it possible to achieve excellent correction accuracy in correcting the posture of the print pattern Pm.

[0262] In this way, the memory unit 101 is configured to store the relative positional relationships V1, V2 between the print pattern Pm set by the print setting unit 304a and each pattern area Rp1, Rp2 for each of the first and second pattern areas Rp1, Rp2 as pattern areas Rp.

[0263] The information stored in the storage unit 101 is not limited to the above-mentioned three types of information. The storage unit 101 may also store evaluation indices for the relative positional relationships V1 and V2 between the first and second pattern regions Rp1 and Rp2.

[0264] Specifically, the storage unit 101 according to this embodiment stores the distance Dx between the first and second pattern regions Rp1 and Rp2 as the evaluation index, as shown by the dashed line in Fig. 23. As shown in the figure, the distance Dx may be the length of a line segment connecting the centers (e.g., centers of gravity) of the first and second pattern regions Rp1 and Rp2.

[0265] The contents stored in step S215, together with other settings, form search conditions, and are stored as search settings in storage unit 101. When creation of the search settings is complete, print setting unit 304a proceeds from step S13 to step S14.

[0266] <6. Operation of Laser Printing System S> FIG. 22 is a flowchart illustrating an operation procedure of the laser printing system S. FIG. 23 is a diagram illustrating a specific example of search settings. FIG. 24 is a diagram illustrating XY misalignment of the workpiece W' during operation. FIG. 25 is a flowchart illustrating the second correction process. FIG. 26 is a flowchart illustrating the second correction process. FIG. 27 is a flowchart illustrating the imaging process in the correction process. FIG. 28 is a flowchart illustrating the process related to pattern search. FIG. 29 is a diagram illustrating the cutting out of the first reference image Pw'. FIG. 30 is a diagram illustrating the pattern search related to the first pattern region Rp1. FIG. 31 is a diagram illustrating the cutting out of the second reference image Pw'. FIG. 32 is a flowchart illustrating the first correction process. FIG. 33 is a diagram illustrating the corrected print pattern Pm.

[0267] Here, Fig. 22 illustrates a specific example of the process in step S3 in Fig. 7. That is, the process shown in Fig. 22 is performed in order for each work W transported to the laser printing device L when the transport line is in operation.

[0268] First, prior to each step shown in Fig. 22, as explained using Fig. 8, Fig. 11 and Fig. 12, the print controller 100 creates in advance settings (print settings) for the print pattern Pm, print block Pb, etc., and settings (search settings) for the pattern image Pp, etc., for a predetermined workpiece W. During the search settings, as shown in Fig. 23, the pattern image Pp corresponding to the pattern area Rp is extracted.

[0269] Once the creation of each setting is complete, the print controller 100 is ready to execute the control process illustrated in Fig. 22. This control process is configured to include, as its main process, a control process for executing XY tracking (steps S303 to S307). Note that "XY tracking" is a pattern search for correcting the print pattern related to XY misalignment, and is referred to as "correction processing" in the figure.

[0270] First, in step S301, when a trigger signal is input from the PLC 902 or the like to the print controller 100, a new workpiece W' different from the workpiece W used for various settings including the pattern area Rp is conveyed.

[0271] Hereinafter, the workpiece W used to set the pattern area Rp, etc. will be referred to as the "preparatory workpiece W," and the new workpiece W' will be referred to as the "correction target W'." These names are merely names for the sake of convenience to simplify the following explanation, and are not intended to limit the use of each workpiece W, W'.

[0272] Here, the print block Pb corresponding to the print pattern Pm is set using a coordinate system defined on the setting surface R2. Therefore, if the correction target W' is misaligned in the X and Y directions relative to the preparation workpiece W, it may not be possible to form the print pattern Pm at the desired position on the correction target W', as shown in FIG.

[0273] Therefore, the printing controller 100 is configured to incorporate new correction amount calculation unit 104 and printing data correction unit 105, and is devised to perform a pattern search for a new work (subject to correction) W' and correct the position and posture of the printing pattern Pm based on the search results.

[0274] (correction processing) The correction process according to this embodiment is performed before the control unit 102 irradiates the print region R1 with the print laser light. In detail, the control unit 102 performs the following correction process before irradiating the correction target W' with the print laser light.

[0275] During the correction process, the control unit 102 controls the laser light scanning unit 4 based on the mode identification information stored in the storage unit 101. After controlling the laser light scanning unit 4, the control unit 102 The coaxial camera 62 or the wide-area camera 7 is controlled so that a new captured image Pw' is acquired.

[0276] The new captured image Pw' here is an image generated by capturing an image of the correction target W', as exemplified in FIG. 24. The new captured image Pw' may be an image generated by the coaxial camera 62, or may be an image generated by the wide-area camera 7. In the former case, the new captured image Pw' will be an image that is smaller and has a higher resolution than the example shown in FIG. 24. The new captured image Pw' may be an image related to the pattern region Rp.

[0277] The new captured image Pw' is an image different from the captured image Pw acquired by capturing an image of the workpiece W from which the pattern region Rp is to be acquired, that is, the preparation workpiece W.

[0278] Furthermore, during the correction process, the correction amount calculation unit 104 identifies the position and orientation of the pattern region Rp in the new captured image Pw' based on the new captured image Pw' and the pattern image Pp stored in the storage unit 101. This identification can be performed, for example, based on image information (pattern image Pp) related to the pattern region Rp.

[0279] The correction amount calculation unit 104 calculates the amount of correction for the position and orientation of the print pattern Pm set by the print setting unit 304ad based on the identified position and orientation and the relative positional relationship stored in the storage unit 101.

[0280] The correction process configured in this manner is illustrated as a first correction process corresponding to the first correction mode and a second correction process corresponding to the second correction mode in steps S305 and S306 of Fig. 22. Below, the flow of Fig. 22 will be explained in detail, along with each correction process that can be executed during the flow.

[0281] (Specific example of correction processing) Returning to FIG. 22, in step S302 following step S301, the print controller 100 reads the mode identification information from the storage unit 101.

[0282] In the following step S303, the print controller 100 determines one print block Pb from among the print blocks Pb for which search conditions have been set in advance, which are designated as the actual correction target during operation, and which correspond to the mode identification information read in step S302.

[0283] In the following step S304, the print controller 100 determines whether or not the second correction mode has been selected based on the mode identification information.

[0284] If the determination is YES, the print controller 100 advances the control process to step S306, where it executes a second correction process based on the multiple (two in this example) pattern areas Rp stored in association with the print block Pb. The second correction process has excellent correction accuracy.

[0285] On the other hand, if the determination in step S304 is NO, the print controller 100 advances the control process to step S305, where it executes a first correction process based on one pattern area Rp stored in association with the print block Pb. The first correction process is superior in processing speed.

[0286] -Second correction process- In step S306, the print controller 100 executes the second correction process illustrated in Fig. 25. The left side of the page, bounded by the dashed dotted line, illustrates the process performed by the control unit 102, and the right side of the page illustrates the process performed by the correction amount calculation unit 104.

[0287] Specifically, in step S401 in Fig. 25, the print controller 100 starts the imaging process for the first search region Rs1. Details of the imaging process are as shown in Fig. 27.

[0288] First, in step S431 of FIG. 27, the control unit 102 selects one of the coaxial camera 62 and the wide-area camera 7 based on the size of the pattern area Rp, for example, the size of the first pattern area Rp1, as illustrated in steps S205 and S209 of FIG. 11.

[0289] In the next step S432, the control unit 102 sets an imaging range for the correction target W' for one of the imaging units selected in step S431. This imaging range may be a range that includes at least the first search region Rs1. Prior to setting the imaging range, the control unit 102 is configured to read the first search region Rs1 from the storage unit 101.

[0290] Furthermore, when the coaxial camera 62 is selected in step S432, the control unit 102 controls the laser light scanning unit 4 to set a desired imaging range. Through this control, the control unit 102 moves the imaging field of the coaxial camera 62 (specifically, the first imaging optical axis A4) to a predetermined location within the imaging range (for example, the center of the imaging range).

[0291] Furthermore, when the wide area camera 7 is selected in step S432, the control unit 102 captures the entire imaging field of the wide area camera 7. In this case, the control unit 102 does not control the laser light scanning unit 4.

[0292] In the following step S433, the control unit 102 waits without starting imaging for the imaging delay set via the 19th interface I19 in Fig. 19. In other words, the control unit 102 starts imaging by the imaging unit when the imaging delay has elapsed.

[0293] In the following step S434, the control unit 102 controls one of the imaging units selected in step S431 to acquire a new captured image Pw'. As illustrated in Fig. 24, the new captured image Pw' is an image that reflects the XY displacement of the correction target W'. Hereinafter, the first search region Rs1, and therefore the new captured image Pw' related to the first pattern image Pp1, will also be referred to as a first reference image Pw'.

[0294] When the process of step S434 is completed, the control unit 102 advances the control process to step S402. In step S402, the control unit 102 inputs a control signal to the correction amount calculation unit 104 to start a pattern search for the first search region Rs1 and the first pattern image Pp1.

[0295] In this configuration example, the processing related to the correction amount calculation unit 104 is executed by the second CPU 100b, not by the first CPU 100a that executes the processing related to the control unit 102. Therefore, the following processing (steps S403 to S405) performed by the control unit 102 and the following processing (step S501) performed by the correction amount calculation unit 104 can be executed in parallel (pipeline processing) while minimizing the load on each CPU as much as possible. This makes it possible to ensure good processing speed.

[0296] In this embodiment, the pipeline processing is performed by the first CPU 100a and the second CPU 100b, but the present disclosure is not limited to such a configuration. In a configuration including a multi-core CPU as described above, as a modified example, the pipeline processing can be performed by sharing it among multiple cores in a single multi-core CPU.

[0297] In step S501 of Fig. 25, the correction amount calculation unit 104 sequentially executes the processes illustrated in Fig. 28. Specifically, in step S531 of Fig. 28, the correction amount calculation unit 104 reads the search conditions created as described above. More specifically, the correction amount calculation unit 104 reads the search conditions corresponding to the print block Pb selected in step S303 of Fig. 22.

[0298] In the following step S532, the correction amount calculation unit 104 acquires the first reference image Pw' acquired in step S434.

[0299] In the following step S533, the correction amount calculation unit 104 generates a search image Ps1 for pattern search based on the first reference image Pw' acquired in step S434.

[0300] In detail, the correction amount calculation unit 104 cuts out an image in the first search region Rs1 from the first reference image Pw' and sets the cut-out image as the search image Ps (see FIG. 29). Hereinafter, the search image Ps cut out from the first reference image Pw' may be referred to as the "first search image Ps1."

[0301] When the coaxial camera 62 is used as the imaging unit, the first reference image Pw' itself may be set as the first search image Ps1. The same applies to the second reference image Pw', which will be described later, and ultimately to the first correction process.

[0302] Although the position and size of the first search area Rs1 on the setting surface R2 are common between the preparatory work W and the correction target W', the content reflected in the first search image Ps1 may change depending on the position and posture of the correction target W' relative to the preparatory work W (see Figures 23 and 24).

[0303] In the following step S534, the correction amount calculation unit 104 specifies the position and orientation of the pattern image Pp in the reference image Pw'. Specifically, the correction amount calculation unit 104 specifies the position and orientation of the first pattern image Pp1 in the first reference image Pw'. More specifically, the correction amount calculation unit 104 specifies the position and orientation of the first pattern image Pp1 in the first search image Ps1.

[0304] Specifically, the correction amount calculation unit 104 moves the first pattern image Pp1 as the correction area so that it is superimposed on the first reference image Pw', more specifically the first search image Ps1, within the range of the first search area Rs1.

[0305] The correction amount calculation unit 104 compares image information (first pattern image Pp1) extracted in advance on the first workpiece W with image information (first search image Ps1 cut out from the first reference image Pw') newly extracted on a different new workpiece W', and finds an area on the first search image Ps1 where the two pieces of image information match more highly than other areas, as shown by the virtual line Sr1 in Fig. 30. This search can be performed based on the level of the correlation value described above.

[0306] The difference between the coordinates of the pattern region Rp before movement (coordinates on the setting surface R2) and the coordinates of the region where the two pieces of image information match more highly than other regions (coordinates on the setting surface R2) as described above is calculated, and this difference can be regarded as the movement amount of the first pattern region Rp1. This movement amount can be detected, for example, in pixel units. As described above, if an area where the two pieces of image information match more highly than other areas is found, the correction amount calculation unit 104 determines that the search was successful, and if no area is found, the correction amount calculation unit 104 determines that the search was unsuccessful. If the search is unsuccessful, the print controller 100 executes the various processes related to the NG determination described above.

[0307] The correction amount calculation unit 104 acquires the coordinates (coordinates on the setting plane R2) of the first pattern image Pp1 after the search is successful (after movement) on the setting plane R2. The correction amount calculation unit 104 also acquires the rotation angle (rotation angle on the setting plane R2) of the first pattern image Pp1 after the search is successful (after movement) on the setting plane R2.

[0308] In this way, the correction amount calculation unit 104 determines the position and orientation of the pattern area Rp, particularly the first pattern area Rp1, in the new captured image Pw' based on the new captured image Pw' obtained by the control unit 102 and the image information (pattern image Pp) stored in the memory unit 101 (see symbol Sr1 in Figures 30 and 33).

[0309] In the following step S535, the correction amount calculation unit 104 calculates the correction amount of the print pattern Pm based on the contents stored in the storage unit 101. This correction amount is based on the position and orientation of the first pattern region Rp1, and may hereinafter be referred to as the "first correction amount."

[0310] Specifically, as described above, the relative positional relationship V1 between the print pattern Pm and the first pattern region Rp1 is stored in the storage unit 101 according to this embodiment. Therefore, the correction amount calculation unit 104 can calculate the correction amount for the position and orientation of the print pattern Pm based on the position and orientation of the first pattern region Rp1 identified in step S534 and the relative positional relationship of the print pattern Pm with respect to the first pattern region Rp1.

[0311] The correction amount calculation unit 104 stores the calculated correction amount, particularly the first correction amount, in the storage unit 101, and ends the processing of step S535 in FIG. 28 and step S501 in FIG.

[0312] On the other hand, when the process of step S402 ends, the control unit 102 advances the control process to step S403 and stores the search image Ps, particularly the first search image Ps1, in the storage unit 101.

[0313] In the next step S404, the print controller 100 starts the imaging process for the second pattern area Rp2. The details of this process are the same as the process in step S401. The elements marked with the word "first" in the above description can be replaced with elements marked with the word "second," along with the reference numerals given to those elements.

[0314] For example, the control unit 102 selects one of the coaxial camera 62 and the wide-area camera 7 based on the size of the second pattern region Rp2 as the imaging unit for imaging processing. The control unit 102 sets an imaging range of the correction target W' for the selected imaging unit. This imaging range may be any range that includes at least the second search region Rs2.

[0315] Furthermore, when the coaxial camera 62 is selected, the control unit 102 controls the laser light scanning unit 4 to set a desired imaging range. Through this control, the control unit 102 directs the imaging field of the coaxial camera 62 to a predetermined location within the imaging range (for example, the center of the imaging range).

[0316] By simultaneously performing the pattern search in step S501 and the control of the laser light scanning unit 4 in step S404, each workpiece W can be processed more quickly.

[0317] Next, the control unit 102 controls the selected imaging unit to acquire a new captured image Pw'. As illustrated in FIG. 24, the new captured image Pw' is an image that reflects the XY displacement of the correction target W'. Hereinafter, the second search region Rs2, and therefore the new captured image Pw' related to the second pattern image Pp2, will also be referred to as the second reference image Pw'. The second reference image Pw' is generated by capturing an image of the same workpiece (the same correction target W') as the first reference image Pw'.

[0318] When the processing for the second reference image Pw' is completed, the control unit 102 advances the control process to step S405. In step S405, the control unit 102 waits until the processing of step S501 executed by the correction amount calculation unit 104 is completed.

[0319] In this way, the control unit 102 in this embodiment is configured to start controlling the laser light scanning unit 4 and the imaging unit to generate the second reference image Pw' while the correction amount calculation unit 104 is identifying the position and orientation of the first correction area (first pattern area Pp1) in the first reference image Pw'.

[0320] In step S405, the control unit 102 acquires the first correction amount calculated by the correction amount calculation unit 104 and the correlation value when the search is successful, and then the control process proceeds to step S406.

[0321] In step S406, the control unit 102 determines whether the correlation value acquired from the correction amount calculation unit 104 is larger than or equal to the lower limit value for the first pattern image Pp1 illustrated in Fig. 19. If the correlation value is equal to or larger than the lower limit value, the control unit 102 advances the control process to step S407. If the correlation value is less than the lower limit value, the control unit 102 terminates the processing shown in Figs. 25 and 22. If the correlation value is less than the lower limit value, the control unit 102 determines that the NG judgment is established, and may execute the various processing described above.

[0322] In step S407, the control unit 102 inputs a control signal to the correction amount calculation unit 104 to start a pattern search for the second search region Rs2 and the second pattern image Pp2.

[0323] The print controller 100 according to this embodiment can execute the following process (steps S407 to S409) performed by the control unit 102 and the following process (step S502) performed by the correction amount calculation unit 104 in parallel while minimizing the load on the CPU as much as possible, thereby ensuring a good processing speed.

[0324] Specifically, in step S502 of Fig. 25, the correction amount calculation unit 104 sequentially executes the processes exemplified in Fig. 28. The details of this process are the same as those of step S501. Elements marked with the word "first" in the above description may be replaced with elements marked with the word "second" together with the reference numerals given to those elements.

[0325] For example, in step S531 of FIG. 28, the correction amount calculation unit 104 reads the search conditions corresponding to the print block Pb selected in step S303.

[0326] Subsequently, the correction amount calculation unit 104 acquires the second reference image Pw' acquired in step S404, and generates a search image Ps2 for pattern search based on the second reference image Pw' (steps S531 to S532).

[0327] 31, the correction amount calculation unit 104 cuts out an image in the second search region Rs2 from the second reference image Pw' and sets the cut-out image as the search image Ps (step S533). Hereinafter, the search image Ps cut out from the second reference image Pw' may be referred to as the "second search image Ps2."

[0328] Although the position and size of the second search area Rs2 on the setting surface R2 are common between the preparatory work W and the correction target W', the content reflected in the second search image Ps2 may change depending on the position and posture of the correction target W' relative to the preparatory work W (see Figures 23 and 24).

[0329] Next, the correction amount calculation unit 104 specifies the position and orientation of the pattern image Pp in the reference image Pw'. More specifically, the correction amount calculation unit 104 specifies the position and orientation (see symbol Sr2 in FIG. 33) of the second pattern image Pp2 in the second reference image Pw'. More specifically, the correction amount calculation unit 104 specifies the position and orientation of the second pattern image Pp2 in the second search image Ps2.

[0330] Specifically, the correction amount calculation unit 104 moves the second pattern image Pp2 as the correction area so that it is superimposed on the second reference image Pw', more specifically the second search image Ps2, within the range of the second search area Rs2.

[0331] The correction amount calculation unit 104 compares image information (second pattern image Pp2) extracted in advance on the first workpiece W with image information (second search image Ps2 cut out from the second reference image Pw') newly extracted on a different new workpiece W', and finds areas on the second search image Ps2 where the two pieces of image information match more highly than other areas, just like the pattern search for the first pattern image Pp1. This search can be performed based on the level of the correlation value described above.

[0332] As described above, if an area where the two pieces of image information match more highly than other areas is found, the correction amount calculation unit 104 determines that the search was successful, and if no area is found, the correction amount calculation unit 104 determines that the search was unsuccessful. If the search is unsuccessful, the print controller 100 executes the various processes related to the NG determination described above.

[0333] The correction amount calculation unit 104 acquires the coordinates (coordinates on the setting plane R2) of the second pattern image Pp2 after the search is successful (after movement) on the setting plane R2. The correction amount calculation unit 104 also acquires the rotation angle (rotation angle on the setting plane R2) of the second pattern image Pp2 after the search is successful (after movement) on the setting plane R2.

[0334] In this way, the correction amount calculation unit 104 determines the position and orientation of the first correction area (first pattern area Rp1) in the first reference image Pw', as well as the position and orientation of the second correction area (second pattern area Rp2) in the second reference image Pw'.

[0335] In the following step S535, the correction amount calculation unit 104 calculates the correction amount of the print pattern Pm based on the contents stored in the storage unit 101. This correction amount is based on the position and orientation of the second pattern region Rp2, and may hereinafter be referred to as the "second correction amount."

[0336] Specifically, as described above, the relative positional relationship V2 between the print pattern Pb and the second pattern region Rp2 is stored in the storage unit 101 according to this embodiment. Therefore, the correction amount calculation unit 104 can calculate the correction amount for the position and orientation of the print pattern Pm, i.e., the second correction amount, based on the identified position and orientation of the second pattern region Rp2 and the relative positional relationship of the print pattern Pm with respect to the second pattern region Rp2.

[0337] The correction amount calculation unit 104 stores the calculated correction amount, particularly the second correction amount, in the storage unit 101, and ends the process of step S502 in FIG.

[0338] On the other hand, when the process of step S407 ends, the control unit 102 advances the control process to step S408 and stores the search image Ps, particularly the second search image Ps2, in the storage unit 101.

[0339] In the following step S409, the control unit 102 waits until the process of step S502 executed by the correction amount calculation unit 104 is completed.

[0340] In step S409, the control unit 102 acquires the second correction amount calculated by the correction amount calculation unit 104 and the correlation value when the search is successful, and then the control process proceeds to step S410.

[0341] In step S410, the control unit 102 determines whether the correlation value acquired from the correction amount calculation unit 104 is larger than or equal to the lower limit value for the second pattern image Pp2 illustrated in Fig. 20. If the correlation value is equal to or larger than the lower limit value, the control unit 102 advances the control process to step S411 in Fig. 26. If the correlation value is less than the lower limit value, the control unit 102 terminates the processing illustrated in Figs. 25 and 22. If the correlation value is less than the lower limit value, the control unit 102 determines that the NG judgment is established, and may execute the various processing described above.

[0342] In step S411 of FIG. 25, the control unit 102 or the correction amount calculation unit 104 determines the relative positional relationship between the first pattern region Rp1 and the second pattern region Rp2 in the new captured image Pw'.

[0343] Specifically, the control unit 102 or the correction amount calculation unit 104 calculates the difference between the coordinates (coordinates on the setting plane R2) of the first pattern image Pp1 after the search is successful (after movement) and the coordinates (coordinates on the setting plane R2) of the second pattern image Pp2 after the search is successful (after movement), as the relative positional relationship. Hereinafter, this difference will be referred to as the "inter-area distance" and will be denoted by the symbol "Dx'" (see FIG. 33). Then, the control unit 102 or the correction amount calculation unit 104 evaluates the results of the correction amount calculation unit 104 identifying the positions and orientations of the first and second pattern areas Rp1 and Rp2 by comparing the determined relative positional relationship (inter-area distance Dx') with the evaluation index (distance Dx) illustrated by the dotted line in Figure 23.

[0344] Specifically, the control unit 102 or the correction amount calculation unit 104 calculates the difference between the inter-area distance and the distance Dx, and if the difference is within a predetermined range, determines that the pattern search has been performed normally. On the other hand, if the difference is outside the predetermined range, the control unit 102 or the correction amount calculation unit 104 determines that the pattern search has not been performed normally, and determines that the above-mentioned NG judgment has been made.

[0345] In step S412 of FIG. 25, the correction amount calculation unit 104 calculates the correction amount for the position and orientation of the print pattern Pm set by the print setting unit 304af based on both the results of identifying the position and orientation of the first pattern area Rp1 and the results of identifying the position and orientation of the second pattern area Rp2.

[0346] Specifically, the correction amount calculation unit 104 calculates the average value of the first correction amount indicating the former specified result and the second correction amount indicating the latter specified result, and sets the calculated result as the final correction amount. In this way, two-point correction is realized. Note that the final correction amount is not limited to the average value. Any correction amount that combines the two correction amounts can be used.

[0347] 33, the first correction amount is obtained by calculating the position Sr1 of the first pattern region Rp1 in the correction target W' and then based on the calculation result and the relative positional relationship V1 between the first pattern region Rp2 and the print block Pb. The second correction amount is obtained by calculating the position Sr2 of the second pattern region Rp2 in the correction target W' and then based on the calculation result and the relative positional relationship V2 between the second pattern region Rp2 and the print block Pb.

[0348] The first and second correction amounts are respectively composed of a correction amount for coordinates in the XY direction and a correction amount for an angle in the rotation direction on the XY plane. In the case of one-point correction, an angle correction amount is required when correcting the attitude. On the other hand, in the case of two-point correction, an angle correction amount is substantially unnecessary when correcting the attitude.

[0349] That is, in the case of two-point correction, it is sufficient to calculate in advance the position vector between the first and second pattern regions Rp1, Rp2 on the preparation workpiece W. Such a position vector can be calculated using only coordinates in the X and Y directions.

[0350] In this case, by calculating the position vector between the first and second pattern regions Rp1, Rp2 in the correction target W' and comparing it with the position vector calculated in advance, the deviation in the posture of the correction target W' relative to the preparatory workpiece W can be obtained. Regardless of the term "position vector," any process based on the correction amounts of coordinates in the X and Y directions is sufficient. Since the correction amounts of angles in the rotational direction that constitute the first and second correction amounts are more difficult to improve accuracy than the correction amounts of coordinates in the X and Y directions, two-point correction, which essentially does not require angle correction amounts, contributes to improving the correction accuracy of the print pattern Pm. This advantage is common to both the coaxial camera 62 and the wide-area camera 7.

[0351] The coaxial camera 62 has excellent resolution, resulting in excellent coordinate correction accuracy. However, the coaxial camera 62 has a narrow field of view (size of the imaging field of view), which can cause problems with measurement accuracy in the rotational direction. In contrast, the position vector described above uses coordinates in the X and Y directions, which have excellent correction accuracy. Therefore, even when the coaxial camera 62 is used, it is possible to detect with high accuracy the deviation in the posture of the correction target W' relative to the preparation work W, and achieve high-precision correction amounts for the posture.

[0352] In the following step S413, the correction amount calculation unit 104 stores the final correction amount thus calculated in the memory unit 101. When the processing of step S413 is completed, the print controller 100 ends the processing of Figures 25 and 26, and advances the control process from step S306 in Figure 22 to step S307 in the same figure.

[0353] -First correction process- Meanwhile, in step S307, the print controller 100 executes the first correction process illustrated in Fig. 32. The left side of the page, bounded by the dashed dotted line, illustrates the process performed by the control unit 102, and the right side of the page illustrates the process performed by the correction amount calculation unit 104.

[0354] The content of the first correction process is the same as that of the second correction process, except that processing related to the second search area Rs2 and the second pattern area Rp2 is omitted and the first correction amount in the second correction process is adopted as the final correction amount.

[0355] That is, the processing in step S601 in FIG. 32 is the same as the processing in step S401 in FIG. 25, the processing in step S602 is the same as the processing in step S402 in FIG. 25, and the processing in step S602 is the same as the processing in step S403 in FIG.

[0356] 25. Furthermore, the processing in step S701 in FIG. 32 is the same as the processing in step S501 in FIG. 25, the processing in step S605 is the same as the processing in step S405 in FIG. 25, and the processing in step S606 is the same as the processing in step S606 in FIG.

[0357] The process of step S613 in FIG. 32 is the same as the process of step S413 in FIG. 26, except that the first correction amount is stored.

[0358] Specifically, in step S613, the correction amount calculation unit 104 stores the correction amount calculated based on one pattern area R in the memory unit 101. When the processing of step S613 is completed, the print controller 100 ends the processing of Fig. 32 and advances the control process from step S305 in Fig. 22 to step S307 in the same figure.

[0359] -Processing after the first and second correction processes- In step S307, the print controller 100 determines whether acquisition of the correction amount for the print pattern Pp has been completed for all print blocks Pb that were set as correction targets. If the determination is NO, the print controller 100 returns the control process to step S303. In this case, the print controller 100 selects another print block Pb in step S303 and executes steps S304 to S306 for that print block Pb.

[0360] If the determination in step S307 is YES, the print controller 100 advances the control process to step S308. In step S308, the print data correction unit 105 corrects, based on the correction amount calculated by the correction amount calculation unit 104, the print data that corresponds to the print pattern Pm for which the correction amount was calculated and that is generated by the print data generation unit 304b.

[0361] By correcting the print data, the position and orientation of the print block Pb are corrected, and the print pattern Pm associated with that print block Pb is also corrected. As shown in Figure 33, a print block Pb' that takes XY offset into account can be provided, and the corrected print pattern Pm' can be printed together with the print block Pb'.

[0362] In the following step S309, the print controller 100 executes laser printing on the workpiece W' via the print head 1 and then returns. Since the XY deviation has already been corrected, the control unit 101 can perform two-dimensional scanning while taking into account the correction amount calculated by the correction amount calculation unit 104.

[0363] <7. How to use the correction modes> As described above, according to the embodiment, the laser printing device L can selectively use a plurality of correction modes each having a different number of pattern areas Rp as correction areas, as described with reference to the first screen Sc1 in Fig. 13. The correction modes can be selectively used. This allows for flexible response to both cases where priority should be given to the accuracy of calculation of the correction amount and cases where priority should be given to the time required to calculate the correction amount, thereby improving user convenience.

[0364] 19 and 20, the processing unit 304 of the setting device 300 can allow the user to visually confirm the estimation results If2 and If3 of the time required to identify the position and orientation of the pattern area Rp. The user can refer to the estimation results and proceed with various user inputs, such as selecting a correction mode. This is advantageous for improving user convenience.

[0365] In general, the coaxial camera 62 that captures the captured images Pw, Pw' via the laser beam scanning unit 4 has superior resolution compared to the wide-area camera 7 that captures the captured images Pw, Pw' without the intervention of the laser beam scanning unit 4. This contributes to higher accuracy of the correction amount. On the other hand, such a coaxial camera 62 requires the laser beam scanning unit 4 to be driven, which is disadvantageous in terms of increasing the speed of the laser beam scanning unit 4. This can have a disadvantageous effect in terms of ensuring the speed at which the correction amount is calculated. The coaxial camera 62 that captures the captured images Pw, Pw' via the laser beam scanning unit 4 can reveal the advantages and disadvantages of using multiple pattern areas Rp.

[0366] 25, the control unit 102 starts controlling the laser light scanning unit 4 and the coaxial camera 62 to generate the second search image Ps2 while the correction amount calculation unit 104 is identifying the position and orientation of the first pattern region Rp1. This improves the calculation speed of the correction amount when considering the entire process for the first pattern region Rp1 and the process for the second pattern region Rp2. This makes it possible to suppress the disadvantages of using multiple pattern regions Rp without losing the advantages of using multiple pattern regions Rp.

[0367] 23, by storing an evaluation index (distance Dw) of the relative positional relationship between the first and second pattern regions Rp1 and Rp2 in the original captured image Pw, it is possible to evaluate the results of identifying the position and orientation of each pattern region Rp when calculating the correction amount in the new captured image Pw, which is advantageous for improving user convenience.

[0368] 11, the laser printing device L selectively uses the coaxial camera 62 and the wide area camera 7 when generating various images used in pattern search. The wide area camera 7 does not require control by the laser light scanning unit 4, and is therefore more advantageous in improving the speed at which correction amounts are calculated than the coaxial camera 62. Providing options for the imaging unit is advantageous in improving user convenience.

[0369] The processing related to the second correction mode is particularly effective when the field of view of the coaxial camera 62 is narrower than that of the workpiece W. By using the coaxial camera 62, high accuracy in correction of positional deviations of each point can be ensured, and high accuracy in the rotation direction can also be ensured by two-point correction.

[0370] Other Embodiments In the embodiment, the region setting unit 304e is configured to use the captured image Pw cut out from the pattern region R, i.e., the pattern image Pp, as image information within the pattern region Rp, but the present disclosure is not limited to this configuration. The region setting unit 304e can also use edge information of the captured image Pw within the pattern region Rp as image information within the pattern region Rp. As described above, in addition to edge information, shape information, color information, and texture information can be used as image information.

[0371] In addition, in the above embodiment, as illustrated in steps S304 to S306 in FIG. 22, the process is configured to branch into the first correction process and the second correction process depending on the mode identification information, but such a configuration is not essential.

[0372] For example, the processing illustrated in Figures 25 and 26 may be started regardless of the mode identification information, and if the first correction mode is selected, steps S404, S407, S408, S409, S410, S411, S412, and S502 in Figure 25 may be skipped.

[0373] In the above embodiment, processing based on one pattern region Rp and processing based on two pattern regions Rp are exemplified, but the present disclosure is not limited to such a configuration. Processing based on three or more pattern regions Rp may also be included. The number of pattern regions Rp is also not limited to two.

[0374] 2 is merely an example. For example, with respect to the print area inspection unit 6, the guide optical axis A2 of the guide light source 61 may branch off from the upstream laser optical axis A11. The first imaging optical axis A4 of the coaxial camera 62 and the distance measurement optical axis A3 of the distance measurement unit 5 may also branch off from a location midway along the laser optical axis A1 connecting the laser light generation unit 2 and the laser light scanning unit 4. [Explanation of symbols]

[0375] S Laser Printing System L Laser Printer 1 print head 2. Laser light generation unit 3 Height direction scanning section 33 Focus adjustment section 4 Laser beam scanning unit 100 Printing Controller 101 Storage section 102 Control section 62 Coaxial camera (imaging unit) 7 Wide-area camera (second imaging unit) 300 Setting device 301 Display section 304a Print setting section 304b Print data generation unit 304i estimation part A4 Imaging optical axis Pw Captured image Pw' New image Pw' First reference image Pw' Second reference image Pm Printing Pattern Pb print block R1 print area R2 setting screen Rp pattern area (correction area) Rp1 First pattern area (first correction area) Rp2 Second pattern area (second correction area) Pp Pattern image (image information) Pp1 First pattern image (image information) Pp2 Second pattern image (image information) Rs Search Area Ps search image Ps1 1st search image Ps2 2nd search image Dx distance (evaluation index) double work W' New Work V1 relative position V2 relative position Dx distance (evaluation index) Dx' relative position

Claims

1. a laser light generating unit that generates a laser light to be irradiated onto a marking area of ​​the workpiece; a laser beam scanning unit that two-dimensionally scans the laser beam generated by the laser beam generating unit within the printing area; an imaging unit having an imaging optical axis branched from the optical axis of the laser light between the laser light generating unit and the laser light scanning unit, and acquiring a captured image by imaging at least a part of the print area via the laser light scanning unit; a display unit that displays a setting surface corresponding to the print area and displays the captured image acquired by the imaging unit on the setting surface; a print setting unit that sets the position and posture of a print pattern to be printed on the workpiece on the setting screen displayed on the display unit; a print data generation unit that generates print data corresponding to the print pattern set by the print setting unit; a correction mode selection unit that selects one correction mode from a plurality of correction modes each having a different number of correction regions for correcting the print data generated by the print data generation unit; an area setting unit that sets the number of correction areas corresponding to the correction mode selected by the correction mode selection unit for the captured image displayed on the display unit; a storage unit that stores, for the number of correction areas corresponding to the correction modes, mode identification information that identifies the correction mode selected by the correction mode selection unit, image information within the correction area set by the area setting unit, and a relative positional relationship between the print pattern and the correction area set by the print setting unit; a control unit that controls the laser beam scanning unit based on the mode identification information stored in the storage unit before irradiating the laser beam onto the printing area, and then controls the imaging unit so that a new captured image different from the captured image is obtained; a correction amount calculation unit that specifies the position and orientation of the correction area in the new captured image based on the new captured image obtained by the control unit and the image information stored in the storage unit, and calculates a correction amount for the position and orientation of the print pattern set by the print setting unit based on the specified position and orientation and the relative positional relationship stored in the storage unit; a print data correction unit that corrects the print data generated by the print data generation unit and that corresponds to the print pattern for which the correction amount has been calculated, based on the correction amount calculated by the correction amount calculation unit; Equipped with A laser printing device characterized by:

2. 2. The laser printing device according to claim 1, an estimation unit that estimates a required time required to identify the position and orientation of the correction region based on the size of the correction region, and displays the estimated required time on the display unit; A laser printing device characterized by:

3. 2. The laser printing device according to claim 1, the storage unit stores, for each of the first and second correction areas as the correction areas, a relative positional relationship between the print pattern set by the print setting unit and the correction area; The imaging unit, together with the laser light scanning unit, is controlled by the control unit to acquire, as the new captured images, a first reference image associated with the first correction area and a second reference image associated with the second correction area, which are generated by capturing an image of the same workpiece as the first reference image; The correction amount calculation unit Identifying both the position and orientation of the first correction area in the first reference image and the position and orientation of the second correction area in the second reference image; calculating a correction amount for the position and orientation of the print pattern set by the print setting unit by combining the result of specifying the position and orientation of the first correction area and the result of specifying the position and orientation of the second correction area; The control unit while the correction amount calculation unit is specifying the position and orientation of the first correction region in the first reference image, the correction amount calculation unit starts to control the laser light scanning unit and the imaging unit to generate the second reference image. A laser printing device characterized by:

4. 4. The laser printing device according to claim 3, the storage unit stores an evaluation index of a relative positional relationship between the first correction area and the second correction area; the correction amount calculation unit determines a relative positional relationship between the first correction area and the second correction area in the new captured image, and evaluates the results of specifying the positions and orientations of the first and second correction areas by the correction amount calculation unit by comparing the determination result with the evaluation index. A laser printing device characterized by:

5. 2. The laser printing device according to claim 1, A second imaging unit that captures an image having a wider field of view than the imaging unit by capturing an image of the workpiece without the intervention of the laser light scanning unit, the control unit selects one of the imaging unit and the second imaging unit based on a size of the correction region, and controls the selected one of the imaging unit and the second imaging unit to acquire the new captured image. A laser printing device characterized by:

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