Laser coloring processing device, laser coloring processing method, and metal coloring material

Abstract

To provide a technique of simultaneously making it possible to control a color and brightness when a pattern is colored on a metal surface.SOLUTION: A laser coloring processing method colors a surface of a metal material 5 by an irradiation data creation step of storing an RGB value of a predetermined color and an irradiation condition of a laser beam emitted from a laser marker 10 for producing a predetermined color to the RGB value in association with each other, an image input step of inputting a drawn image, an image creation step of creating an image so that an input drawn image is constituted of a plurality of pixels colored on the basis of an area ratio of RGB, brightness addition processing of adding a white region separately from the region occupied by the RGB in each pixel constituting the image to be created, and adding brightness on the basis of an area ratio of the region of the RGB to the white region, and an irradiation condition output step of extracting the irradiation condition of the laser beam of each of the pixels on the basis of the area ratio of the RGB allocated to each of the pixels by the image creation processing and the brightness addition processing to the white region, and outputting it to the laser marker 10.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a metal coloring material having a structure in which the color produced by processing using a laser can be adjusted along with the brightness, and to a coloring processing method and coloring processing device for a metal material using a laser. [Background technology]

[0002] Conventionally, one method for color marking the surface of a workpiece is a laser color marking method in which a liquid containing metal colloids is applied to the surface of the workpiece, and a laser beam is irradiated onto the applied liquid or the liquid that has been dried after application to coagulate the metal colloids and produce a color marking (see, for example, Patent Document 1).

[0003] However, the conventional laser color marking method requires coating the surface of the workpiece with a metal colloid, which makes the processing process complicated. In addition, depending on the laser irradiation intensity, cracks may occur in the metal colloid coating layer, making it difficult to set the laser irradiation conditions for the thickness of the metal colloid coating film.

[0004] In order to solve this problem, a laser coloring processing method and processing device have been developed that color the surface of a metal material by the following steps (for example, see Patent Document 2): an irradiation data generation step of storing in an irradiation data generation unit a first RGB value of a predetermined color for a metal material to be drawn, and irradiation conditions of laser light for producing the predetermined color in response to the first RGB value; an image input step of inputting a drawing image to be drawn on the surface of the metal material; an area division step of dividing areas of the drawing image by replacing the RGB value of each pixel of the drawing image with the first RGB value so that the second RGB value of each pixel of the input drawing image is closest to the first RGB value stored in the irradiation data generation unit under predetermined conditions; and an irradiation condition output step of extracting irradiation conditions of laser light for each pixel from the irradiation data generation unit based on the first RGB value assigned to each pixel in the area division step, and outputting them to a laser marker. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2003-094181 A [Patent Document 2] JP 2020-151762 A Summary of the Invention [Problem to be solved by the invention]

[0006] The technology described in Patent Document 2 above has the advantages of simplifying the processing method and making it easier to set the laser irradiation conditions, and by combining a large number of minute cells with oxide films of different thicknesses, it is possible to produce a very large number of colors.

[0007] However, although it is possible to produce multiple colors, it is not possible to change the brightness of each cell. In other words, there is a problem in that multiple cells of the same hue cannot each have a different brightness.

[0008] The present invention has been made to solve at least part of the above-mentioned problems, and aims to provide a technology that makes it possible to simultaneously control color and brightness when coloring a pattern or the like on a metal surface. [Means for solving the problem]

[0009] The present invention can be realized as the following application examples. Note that the reference symbols and supplementary explanations in parentheses in this section indicate the correspondence with the embodiments described later in order to facilitate understanding of the present invention, and do not limit the present invention in any way.

[0010] [Application example 1] The invention described in Application Example 1 is as follows: A laser coloring processing device (1) that draws a colorable image on a surface of a metal material (5) by laser light irradiated from a laser irradiation unit (10), an irradiation data generating unit (30) that, when causing a metal material (5) to be drawn to develop a predetermined color, stores an RGB value of the predetermined color in association with irradiation conditions of the laser light irradiated from the laser irradiation unit (10) for developing the predetermined color according to the RGB value; an image input unit (20) for inputting a drawing image to be drawn on the surface of the metal material (5); A drawing image inputted by the image input unit (20), Formed RGB Oxide film an image generating unit (30) that generates an image so as to be composed of a plurality of pixels that emit colors based on an area ratio; Each pixel constituting the image generated by the image generating unit (30) Within In this case, a white or black area is added in addition to the RGB area, Formed in each pixel The RGB Oxide film Area and , are formed within the same pixel The white or black Oxide film a brightness adding unit (30) that adds brightness based on the area ratio of the regions; The image generating unit (30) and the brightness adding unit (30) Inside an irradiation condition output unit (30) that extracts irradiation conditions of the laser light for each pixel from the irradiation data generation unit (30) based on the area ratio of the RGB and white or black regions assigned to the pixel, and outputs the extracted conditions to the laser irradiation unit (10); The present invention relates to a method for producing a color on the surface of the metal material (5).

[0011] In such a laser processing coloring processing device (1), when drawing on the surface of a metal material (5), a plurality of pixels used for drawing are Inside When color processing is performed using RGB, a white or black area is provided in addition to the area where an image is formed using RGB. In other words, one pixel is composed of RGB and white or black.

[0012] The brightness of each pixel is then set based on the area ratio between the RGB region and the white or black region. Since the image drawn on the metal material (5) is a collection of pixels, it is also possible to set the brightness of the entire image.

[0013] [Application example 2] The invention described in Application Example 2 is as follows: A laser coloring processing method for drawing a colorable image on a surface of a metal material (5) by laser light irradiated from a laser irradiation unit (10), comprising: an irradiation data generating step of, when a predetermined color is to be developed on a metal material (5) to be drawn, associating an RGB value of the predetermined color with irradiation conditions of the laser light to be irradiated from the laser irradiation unit (10) for developing the predetermined color corresponding to the RGB value, and storing the associated data in an irradiation data generating unit (30); an image input step of inputting a drawing image to be drawn on the surface of the metal material (5); The drawing image input in the image input step is Formed RGB Oxide film an image generating step of generating an image so as to be composed of a plurality of pixels which are colored based on an area ratio; Each pixel constituting the image generated in the image generating step Within In this case, a white or black area is added in addition to the RGB area, Formed in each pixel The RGB Oxide film Area and , are formed within the same pixel In the white or black area Oxide film Add brightness based on area ratio Process and, Image Generation Process And the brightness added Process an irradiation condition output step of extracting irradiation conditions of the laser light for each pixel from the irradiation data generation unit (30) based on the area ratio of the RGB and white or black regions assigned to each pixel by the above-mentioned, and outputting the extracted conditions to the laser irradiation unit (10); The present invention relates to a method for producing a color on the surface of the metal material (5).

[0014] According to this processing method, the same effects as those of the laser coloring processing device (1) described in Application Example 1 can be obtained.

[0015] [Application example 3] The metal color-developing material (2) described in Application Example 3 is Metallic materials (5); Pixels constituting an image to be drawn on the surface of the metal material (5) In , An oxide film formed by irradiation with laser light, RGB Values Area ratio based on Formed by RGB Area and An oxide film formed by irradiation of a laser beam, the RGB region being formed in the same pixel as the pixel in which the RGB region is formed. White or black areas separate from the Black and white formed by area ratio Area and 、 The above The RGB area and the black and white area an oxide film layer (7) that develops color by thin-film interference between incident light that is incident on the oxide film (6) and reflected light that is transmitted through the oxide film (6) and reflected by the surface of the metal material (5); The gist of the system is that it is equipped with the following:

[0016] In such a metal coloring material (2), an oxide film (6) is formed on the surface of the metal material (5), and coloring occurs due to thin-film interference between incident light and reflected light on the oxide film (6). At that time, the pixels that make up the image to be drawn on the surface of the metal material (5) are Formed within the pixel, It consists of an area formed by RGB values ​​and the other areas that are white or black.

[0017] In this way, the pixels of the image formed on the surface of the metal material (5) Within There are areas formed by RGB values ​​and areas formed by white or black. The brightness of each pixel can be determined by the existence of areas formed by white or black other than the area formed by RGB values.

[0018] In addition, by changing the area ratio of the area formed in white or black other than the area formed by RGB values, the brightness of each pixel can be changed, and as a result, a metal color-producing material (2) can be obtained that can change the brightness of the entire image. [Brief description of the drawings]

[0019] [Figure 1] 1 is a block diagram showing a schematic configuration of a laser coloring processing device; [Diagram 2] 4 is a flowchart showing a flow of processing executed by a control unit. [Diagram 3]FIG. 13 is a diagram showing color samples in the case of eight continuous pulses of laser light (pattern 8). [Figure 4] FIG. 13 is a diagram showing the result of drawing a color image on the surface of a metal material using a color image. [Diagram 5] FIG. 13 is a diagram showing an example of a color marking database. [Figure 6] FIG. 1 is a diagram conceptually illustrating the difference between a conventional color-developing method and the color-developing method according to the present invention. [Figure 7] FIG. 13 is a diagram showing the results of changing the hue and brightness of a square pixel (cell). [Figure 8] 1 is a diagram showing a schematic configuration of a metal color-producing material and a color-producing principle. [Figure 9] FIG. 11 is a diagram showing the state of an oxide film layer of a metal coloring material in a second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] Hereinafter, an embodiment to which the present invention is applied will be described with reference to the drawings. Note that the embodiment of the present invention is not limited to the following embodiment, and various forms may be adopted as long as they fall within the technical scope of the present invention.

[0021] [First embodiment] (Configuration of laser color processing device) The configuration of the laser coloring processing apparatus 1 will be described with reference to Fig. 1. Fig. 1 is a block diagram showing a schematic configuration of the laser coloring processing apparatus 1.

[0022] As shown in FIG. 1, the laser coloring processing device 1 includes a laser marker 10, an image input unit 20, and a control unit 30. The laser marker 10 is a device that irradiates laser light based on control data from a control unit 30 described later, and the irradiated laser light generates heat on the surface of the metal material 5, and the generated heat causes an oxide film to grow and color the surface of the metal material 5. In this embodiment, an MX-Z2000G manufactured by Omron Corporation is used as the laser marker 10.

[0023] The image input unit 20 is a so-called scanner, and is a device that reads images to be drawn on the surface of the metal material 5 as digital data from characters, pictures, figures, drawings, photographs, etc. drawn on paper or the like.

[0024] The control unit 30 is a device that controls the laser marker 10 based on the laser light irradiation conditions input by the image input unit 20, and is equipped with a CPU, ROM, RAM, I / O, external storage device, keyboard, display device, etc., which are not shown.

[0025] Here, the control process executed by the control unit 30 will be described with reference to Fig. 2. Fig. 2 is a flowchart showing the flow of the process executed by the control unit 30. 2, in the control process, first, in S100, a CPU (not shown) of the control unit 30 generates and stores a color marking database. The laser light irradiation conditions (color marking database) for making the surface of the metal material 5 develop a predetermined color are stored.

[0026] This will be explained in detail. Each pixel of the image data has 8 bits for each of RGB, that is, each pixel has 256 gradations for each of RGB, and these values ​​are called RGB values. The laser irradiation conditions are the pattern (number of continuous pulses), frequency (pulse period), and power (pulse height).

[0027] The list that associates the RGB values ​​of each pixel with the laser irradiation conditions is called a color marking database. In this embodiment, to create a color marking database, color samples were created in the laser marker 10 by changing patterns from 1 to 15, frequencies from 25 to 825 kHz in 25 kHz increments, and power from 20 to 50% of maximum output in 1% increments.

[0028] Figure 3 shows a color sample for pattern 8 (8 continuous pulses). In Figure 3, the bottom left rectangle is drawn with a power of 20% and a frequency of 25 kHz, with the power increasing by 1% in the upward direction and the frequency increasing by 25 kHz in the rightward direction. Based on the created color samples and their spectra measured by a colorimeter, the developed colors were associated with the laser irradiation conditions.

[0029] Then, a list in which the RGB values ​​of the input image correspond to the irradiation conditions of the laser light for drawing is created as a color marking database and stored in an external storage device. In this embodiment, the number of color marking databases is set to N (color numbers 0, 1, 2, . . . , n-1, n, . . . N: when N = 256, color number n = 0 to 255).

[0030] For colors that cannot be produced under the laser irradiation conditions, the ratio of multiple colors produced in the vicinity of the color space is calculated to generate the color for each pixel. Since there is a trade-off between the improvement in vividness of the drawn image by increasing the number of colors and the drawing time, a color marking database with the number of colors required is created.

[0031] Also, the number of colors required varies depending on the image to be colored. Therefore, a method is added in which the color distribution is obtained by processing the input image, the number of colors required is calculated based on the color distribution, and a color marking database is automatically generated that associates the relationship between the image color, the color generated, the laser irradiation conditions, and the cell structure. By realizing this, it is possible to automatically create the clearest marking database possible with the laser marker 10 owned, without making any changes to the input image or the laser irradiation conditions, etc.

[0032] In the next step S105, the image to be drawn is input. That is, the image to be drawn on the surface of the metal material 5 is read by the image input unit 20 and input as digital data. In the next step S110, region division is performed. That is, the image read by the image input unit 20 (hereinafter referred to as the "input image") is divided into N regions specified in the color marking database, and the ratio of the white region is set for each divided region.

[0033] The division method is to find the color number n whose RGB value is closest to the RGB value of each pixel in the input image in the color marking database of N colors. The Euclidean distance is used to determine the distance between the RGB values. A region division image is generated with the color number n obtained in this way as the pixel value.

[0034] Here, the Euclidean distance means the distance between each element (R, G, B) of a plurality of RGB values. More specifically, if there are a first RGB value (R1, G1, B1) and a second RGB value (R2, G2, B2), the Euclidean distance between them is (R2-R1). 2 +(G2-G1) 2 +(B2-B1) 2 is the square root of .

[0035] For each color number n, contour extraction is performed on the divided image, and the coordinate values ​​of the consecutive pixels that form the contour are stored as region data in a predetermined data format (DXF format in this embodiment) in a RAM or external storage device (not shown). The coordinate values ​​have the lower left corner of the image as the origin, the right direction is the X axis, and the upward direction is the Y axis.

[0036] Then, the width of the drawing is calculated and the enlarged or reduced coordinate values ​​are stored in the RAM or an external storage device. Next, in S115, the laser light irradiation conditions are output to the laser marker 10. That is, for the area data of each color and the white area data obtained in S110, the laser irradiation conditions are set in accordance with the color marking database, and a superposition of all colors including white is output to the laser marker 10 as the laser irradiation conditions.

[0037] (Test Results) 4 to 6, the results of actually drawing on the surface of a metal material 5 using the laser coloring processing device 1 will be described. FIG. 4 is a diagram showing the result of drawing a color image on the surface of a metal material 5 using a color image.

[0038] Fig. 4(b) shows the result of dividing the input image shown in Fig. 4(a) into regions according to the color pattern shown in Fig. 5, and Fig. 4(c) shows the result of drawing on the metal material 5. As shown in Fig. 4(c), a color image can be obtained. Note that no brightness setting is made in Fig. 4.

[0039] (Explanation of adding brightness) Here, with reference to Fig. 6, a conventional method of dividing a color image into colors on a metal material 5 using laser light and a method capable of setting the brightness of an image will be described while comparing the differences. Fig. 6 is a diagram conceptually explaining the difference between the conventional color-developing method and the color-developing method according to the present invention. Fig. 6(a) shows the conventional color-developing method in which only RGB values ​​are set, and Fig. 6(c) shows the color-developing method according to the present invention.

[0040] As shown in Figure 6(b), with the conventional color-developing method, the color of a pixel could be gradually changed from red to purple to blue by changing the RGB values ​​in a pixel, i.e., the RGB area ratio in a pixel (r:(1-r)).

[0041] In Figures 6(a) and 6(b), the pixel color is purple, so RGB changes the hue of purple by changing the area ratio between the area r that produces R (red) and the area (1-r) that produces B (blue). In Figure 6(a), the height of each pixel is the same, so the surface area ratio is shown as the horizontal length r:(1-r). The same is true for Figures 6(c) and 6(d).

[0042] In contrast, in the method of the present invention, as shown in FIG. 6(c), the hue is created by changing the area ratio of the area indicated by a in one pixel that develops color based on RGB values ​​in the same manner as in the conventional method (the area ratio is represented as b:(1-b)).

[0043] At the same time, a white area (the area indicated by (1-a) in FIG. 6(b)) is formed in the area other than the above area. Then, as shown in FIG. 6(d), by changing the area ratio between the area formed based on the RGB values ​​and the white area (a:(1-a)), it becomes possible to change the brightness of the pixel.

[0044] The coloring results obtained by this are shown in FIG. 7. FIG. 7 shows the results of changing the hue and brightness of a square pixel (cell) with one side of 100 μm, where FIG. 7(a) shows the marking result, and FIG. 7(b) shows the change in hue when the RGB value is changed (corresponding to (b) in FIG. 7(a)). FIG. 7(c) shows the change in brightness when the area ratio of the area forming R (red) of RGB to the area forming white is changed (corresponding to (c) in FIG. 7(a)). FIG. 7(d) shows the change in brightness when the area ratio of the area forming B (blue) of RGB to the area forming white is changed (corresponding to (d) in FIG. 7(a)). In FIG. 7(b) to FIG. 7(d), the horizontal axis shows the wavelength [nm], and the vertical axis shows the reflectance [%].

[0045] For the marking, a flat plate of SUS304 was used as the metal material 5, and the changes in hue and brightness are shown as spectral data measured by a colorimeter. Figure 7(a) shows the change in hue obtained by changing the area ratio of the two colors red and blue in the horizontal direction, and the change in lightness obtained by changing the area ratio to the white area in the vertical direction for the same hue.

[0046] As shown in FIG. 7(a), the larger the white area is (the further down in the vertical direction), the brighter it is. In FIG. 7(b), the area ratio of R:G is indicated as "A" for 0:100, "B" for 25:75, "C" for 50:50, "D" for 75:25, and "E" for 0:100. As shown in FIG. 7(b), it can be seen that the desired hue (the reflectance of the resulting color at its wavelength) can be obtained by adjusting the R:G area ratio.

[0047] In Figure 7(c), the area ratio of the R region to the white region is indicated as "F" for 0:100, "G" for 25:75, "H" for 50:50, "I" for 75:25, and "J" for 0:100. In addition, in FIG. 7(d), the area ratio of the B region to the white region is indicated by "K" for 0:100, "L" for 25:75, "M" for 50:50, "N" for 75:25, and "O" for 0:100.

[0048] As shown in FIG. 7(c) and FIG. 7(d), it is understood that the brightness of the desired hue can be changed by changing the area ratio between the RGB region and the white region.

[0049] (Features of the laser color processing device) In such a laser processing coloring processing device 1, when drawing on the surface of the metal material 5, each of the multiple pixels used for drawing is colored with RGB, and a white area is provided in addition to the area where the image is formed with RGB of the pixel. In other words, one pixel is composed of RGB and white or black.

[0050] The brightness of each pixel is then set based on the area ratio between the RGB region and the white region. Since the image drawn on the metal material 5 is a collection of pixels, it is possible to set the brightness of the entire image.

[0051] In addition, because the brightness can be changed for each pixel, it is also possible to create a brightness distribution within an image. In other words, even if the entire surface of an image is the same color, it is possible to change the brightness depending on the position in the image and create a brightness distribution.

[0052] (Metal coloring materials) The metal color-developing material 2 will be described with reference to Fig. 8. Fig. 8 is a diagram showing the schematic configuration and color-developing principle of the metal color-developing material 2.

[0053] As shown in FIG. 8, the metal color-developing material 2 includes a metal material 5 and an oxide film layer 7 formed on the surface of the metal material 5. The metal material 5 is a material to be drawn, and is a metal material such as stainless steel or titanium. The oxide film layer 7 is a layer formed on the surface of the metal material 5 by irradiating the surface of the metal material 5 with laser light from a laser marker 10 while changing the irradiation conditions for each pixel of the image to be drawn, thereby forming an oxide film 6 with different characteristics for each pixel on the surface of the metal material 5.

[0054] In each pixel of the oxide film layer 7 formed on the surface of the metal material 5, an oxide film 6 having different characteristics (film thickness d: in this embodiment, d = several hundred [nm]) is formed depending on the laser light irradiation conditions (pattern (number of continuous pulses), frequency (pulse period), power (pulse height)).

[0055] 8, light (visible light of 380 to 780 [nm]) reflected on the surface of the oxide film 6 (optical path A) and light (optical path B) that passes through the oxide film 6 and is reflected on the surface of the metal material 5 interfere with each other to produce color. Since such interference occurs at each pixel, a coloring effect is obtained at the drawing layer, which is a collection of each pixel.

[0056] [Second embodiment] Next, a second embodiment will be described with reference to Fig. 9. In the second embodiment, the configuration of the laser coloring processing device 1, the creation of the color marking database, the area division, and the output of the control data are the same as those in the first embodiment, and therefore the description thereof will be omitted.

[0057] (Oxide layer formation) In the metal coloring material 2 in the second embodiment, the oxide film layer 7 divides an image to be drawn into a plurality of regions 40 (hereinafter also referred to as cells 40) instead of pixels, and the divided plurality of cells 40 are further divided into subcells 41, 42, and 43. Then, by irradiating the laser light under different irradiation conditions for each of the subcells 41 and 42, oxide films 6 with different characteristics are formed for each of the subcells 41 and 42. Also, the subcell 43 is a white region.

[0058] A detailed description will be given with reference to Fig. 9. Fig. 9 is a diagram showing the state of the oxide film layer 7 of the metal color developing material 2 in the second embodiment. An input image shown in Fig. 9(a) is divided into color regions. Fig. 9(b) shows a diagram of a red region as a divided color region. As shown in Fig. 9(c), the red region is divided into a plurality of matrix-shaped cells 40. As shown in Fig. 9(d), each divided cell 40 is further divided into rectangular sub-cells 41, 42, and 43 (white regions), and laser light is irradiated to each of them under different irradiation conditions.

[0059] As a result, the oxide films 6 formed in the subcells 41, 42, and 43 have different thicknesses, so that the subcells 41, 42, and 43 emit different colors (for example, R, G, and white). In practice, the subcells 41, 42, and 43 may be formed within the cell 40 by scanning the laser light emitted by the laser marker 10.

[0060] In this way, by scanning the laser light within each cell 40, subcells 41, 42, and 43 are formed, and each subcell 41, 42, and 43 emits a different color. If the size of cell 40 is sufficiently small, the colors of each subcell 41, 42, and 43 are synthesized, making it possible to emit many colors and change the brightness.

[0061] In FIG. 9, subcells 41, 42, and 43 are formed as rectangles of the same size and area ratio, and each emits R, G, and B, respectively; however, the number of subcells constituting cell 40, the arrangement of the subcells, the shape of the subcells, the size of the subcells, the area ratio of the subcells, and the conditions for irradiating the laser on the subcells can be freely set.

[0062] This makes it possible to improve the color resolution and brightness resolution, and also makes it possible to express fine patterns, which is effective for texture images.

[0063] [Other embodiments] (1) In the above embodiment, the area to which brightness is to be added is formed in white, but it may be formed in black.

[0064] (2) In the above embodiment, a scanner is used as the image input unit 20, but other input devices may also be used. (3) In the above embodiment, each pixel has 256 gradations, each of which is 8 bits for RGB. However, depending on the performance of the CPU of the control unit 30, the pixel may have a different number of bits.

[0065] (4) In the above embodiment, the MX-Z2000G manufactured by Omron Corporation, which generates laser light in pulses, was used as the laser marker. However, other types of laser markers may also be used, such as a type in which intensity is controlled by the number of pulses per unit time or a type in which intensity is controlled by the pulse width.

[0066] (5) In the above embodiment, the spectrum measured by a colorimeter was used to create the color marking database. However, the color marking database may also be created by associating visually observed colors with laser irradiation conditions.

[0067] Alternatively, it may be determined by the color difference between the color of each pixel in the image and the color of a color marking database of N colors. The color difference may be determined by expressing the color as La*b* values ​​and determining LAB ΔE.

[0068] (7) In the above embodiment, the laser light is scanned when irradiating the metal material 5, but the oxide film 6 may be formed on the metal material 5 by relatively moving the laser marker 10 and the metal material 5 parallel to the surface of the metal material 5. When moving the laser marker 10 and the metal material 5 relative to each other, the movement does not necessarily have to be linear, and the movement may be more complex, such as a triangular wave or circular movement.

[0069] (8) In the above embodiment, the pixels whose brightness is changed are rectangular and the color area and the white (or black) area are divided vertically. However, it is possible to change the area ratio between the color area and the white (or black) area, and a Bayer pattern or the like may be used. The pixel shape may also be a shape other than a rectangle, such as a circle.

[0070] (9) In the above embodiment, the laser marker 10 was controlled using frequency and output as parameters. However, the laser marker 10 may also be controlled using parameters other than frequency and output, such as scanning speed, number of scans, and focal length. [Explanation of symbols]

[0071] REFERENCE SIGNS LIST 1... laser coloring processing device 2... metal coloring material 5... metal material 6... oxide film 7... oxide film layer 10... laser marker (laser irradiation section) 20... image input section 30... control section (irradiation data generation section, image generation section, brightness addition section, irradiation condition output section) 40... area (cell) 41, 42, 43... sub-cells.

Claims

1. A laser color processing device that draws a colorable image on a surface of a metal material by laser light irradiated from a laser irradiation unit, an irradiation data generating unit that, when a predetermined color is to be developed on a metal material that is to be drawn, stores RGB values ​​of the predetermined color in association with irradiation conditions of the laser light to be irradiated from the laser irradiation unit for developing the predetermined color according to the RGB values; an image input unit for inputting a drawing image to be drawn on a surface of the metal material; an image generating unit that generates an image based on the drawing image input by the image input unit so as to be composed of a plurality of pixels that develop colors based on the area ratio of the RGB oxide films to be formed; a brightness adding section which adds a white or black area in addition to the area occupied by RGB in each pixel constituting an image generated by the image generating section, and adds brightness based on an area ratio between the RGB oxide film area formed in each pixel and the white or black oxide film area formed in the same pixel; an irradiation condition output unit that extracts irradiation conditions of the laser light for each pixel from the irradiation data generation unit based on the area ratio of the RGB and the white or black area allocated to each pixel by the image generation unit and the brightness addition unit, and outputs the extracted conditions to the laser irradiation unit; A laser coloring processing device which colors the surface of the metal material by

2. A laser coloring processing method for drawing a colorable image on a surface of a metal material by laser light irradiated from a laser irradiation unit, comprising: an irradiation data generating step of, when a predetermined color is to be developed on a metal material to be drawn, associating an RGB value of the predetermined color with irradiation conditions of the laser light to be irradiated from the laser irradiation unit for developing the predetermined color corresponding to the RGB value, and storing the associated data in an irradiation data generating unit; an image input step of inputting a drawing image to be drawn on the surface of the metal material; an image generating step of generating an image based on the drawing image input in the image input step so as to be composed of a plurality of pixels which develop colors based on the area ratio of the RGB oxide films to be formed; a brightness addition process for adding a white or black area in addition to the area occupied by RGB in each pixel constituting the image generated in the image generation process, and adding brightness based on an area ratio between the RGB oxide film area formed in each pixel and the white or black oxide film area formed in the same pixel; an irradiation condition output step of extracting irradiation conditions of the laser light for each pixel from the irradiation data generation unit based on the area ratio of the RGB and the white or black region assigned to each pixel by the image generation step and the brightness addition step, and outputting the extracted conditions to the laser irradiation unit; A laser coloring processing method, characterized in that the surface of the metal material is colored by the laser.

3. A metal material; In the pixels constituting the image to be drawn on the surface of the metal material, an oxide film formed by irradiating a laser beam, the oxide film having RGB regions formed with an area ratio based on RGB values; an oxide film formed by irradiating the RGB region with a laser beam, the black-and-white region being formed in the same pixel as the pixel in which the RGB region is formed, with a white or black region different from the RGB region being formed in an area ratio; an oxide film layer that develops colors by thin-film interference between incident light that is incident on an oxide film in the RGB region and the black and white region and reflected light that is transmitted through the oxide film and reflected on a surface of the metal material; A metal color-developing material comprising:

Images