Method, apparatus, device, and program for coloring metal surface based on femtosecond laser

Abstract

The application relates to the technical field of laser processing, in particular to a metal surface coloring method, device, equipment and program based on femtosecond laser. The metal surface coloring method based on femtosecond laser provided by the application is a kind of laser processing technology, and the process itself has no health hidden danger and has no environmental protection problem. By introducing the parameter of the number of sub-pulses in each emitted pulse string for processing, the heat can be moderately accumulated on the metal surface during processing, the generation of the microstructure is affected, the processing surface is more smooth, the color gamut of coloring is expanded, and better coloring effect is achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of laser processing, in particular to a metal surface coloring method, device, equipment and program based on femtosecond laser. BACKGROUND

[0002] The method of coloring metal surface using laser is gradually popularized and applied. The principle is to directly act on the metal surface by laser to induce the formation of periodic surface structure (LIPSS) or oxide film and other microstructures on the metal surface. These microstructures diffract or interfere under light to display color.

[0003] At present, the laser-based metal surface coloring technology includes nanosecond laser coloring technology based on master oscillator power amplifier (MOPA) architecture. This technology has advantages in color angle stability and color gamut range, but is limited by the long pulse width and serious heat accumulation which easily leads to thermal deformation of the substrate. Another technology is single-pulse femtosecond laser coloring technology. This technology has not been commercialized, has the advantages of ultra-short pulse and low heat, but the metal surface processed by this technology is prone to form rough laser-induced structure, which severely limits the color gamut range.

[0004] In summary, there is an urgent need to develop a new laser coloring method to improve the effect of coloring metal surface using laser. SUMMARY

[0005] The present application provides a metal surface coloring method, device, equipment and program product based on femtosecond laser, introduces the number of sub-pulses in each emitted pulse string as a new parameter, and synchronously matches appropriate general parameters to form a processing parameter combination for laser coloring, thereby obtaining better laser metal coloring effect.

[0006] In order to achieve the above purpose, the main technical scheme adopted by the present application includes:

[0007] In a first aspect, the present application provides a metal surface coloring method based on femtosecond laser, which comprises:

[0008] According to the matching of the target color in the preset two-dimensional color palette, the processing parameter combination corresponding to the target color is obtained, wherein the two-dimensional color palette is generated by changing the general parameters of laser processing and the number of sub-pulses in each emitted pulse string, and different colors are generated on the metal surface and recorded.

[0009] According to the processing parameter combination, the femtosecond laser is used to color the surface of the target metal.

[0010] The method for coloring metal surface based on femtosecond laser proposed in the embodiments of the present application is a laser processing technology, which has no health risks and environmental problems. By introducing the parameter of the number of sub-pulses in each emitted pulse train, the heat can be accumulated on the metal surface during processing, the microstructure generation is affected, and the processing surface is smoother, so that the color gamut is expanded and better coloring effect is achieved.

[0011] In a second aspect, the embodiments of the present application provide a device for coloring metal surface based on femtosecond laser, which comprises:

[0012] A matching module is configured to match a target color in a preset two-dimensional color palette to obtain a processing parameter combination corresponding to the target color, wherein the two-dimensional color palette is generated by changing the general parameters of laser processing and the number of sub-pulses in each emitted pulse train to generate different colors on the metal surface and record them.

[0013] A processing module is configured to use femtosecond laser to color the surface of a target metal according to the processing parameter combination.

[0014] In a third aspect, the embodiments of the present application provide a computer device, which comprises:

[0015] A memory and a processor are communicatively connected, and the memory stores computer instructions. The processor executes the computer instructions to perform the method for coloring metal surface based on femtosecond laser according to the first aspect.

[0016] In a fourth aspect, the embodiments of the present application provide a computer program product comprising computer instructions for causing a computer to perform the method for coloring metal surface based on femtosecond laser according to the first aspect. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the drawings needed in the description of the embodiments or the prior art will be briefly introduced. Obviously, the drawings in the following description are some embodiments of the present application, and those skilled in the art can obtain other drawings without creative labor based on these drawings.

[0018] Figure 1 A step diagram of the method for coloring metal surface based on femtosecond laser provided by the embodiments of the present application is provided.

[0019] Figure 2 A working condition schematic diagram of a laser based on different numbers of sub-pulses provided by the embodiments of the present application is provided.

[0020] Figure 3 A working condition diagram of a laser based on different scanning speeds and sub-pulse numbers is provided for the embodiments of the present application.

[0021] Figure 4 A diagram showing the changes in the microstructure of a titanium surface as the number of sub-pulses increases is provided for the embodiments of the present application.

[0022] Figure 5 A preset two-dimensional color palette diagram is provided for the embodiments of the present application.

[0023] Figure 6 An example of a processing result of a titanium metal is provided for the embodiments of the present application.

[0024] Figure 7 A structural diagram of a metal surface coloring device based on a femtosecond laser is provided for the embodiments of the present application.

[0025] Figure 8 A structural diagram of a computer device is provided for the embodiments of the present application. DETAILED DESCRIPTION

[0026] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described below in detail with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some but not all of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of the present application.

[0027] Currently, mainstream metal product surface coloring still uses chemical dyeing processes, such as directly using organic ink for coloring or using strong oxidizing electrolyte for anodic oxidation coloring. Such methods may leave chemical reagents on the surface of metal products, causing hidden dangers to the health and safety of users, and the manufacturing process may also cause environmental burdens due to the large use of chemical reagents.

[0028] To avoid the above problems, the method of using laser for metal surface coloring is gradually being popularized and applied. Laser coloring technology directly acts on the metal surface through laser, inducing the formation of laser-induced periodic surface structure (LIPSS) or oxide film microstructure on the metal surface. These microstructures exhibit color under light due to diffraction or interference effects. Generally, the color of LIPSS is highly dependent on the observation angle, lacks angle stability, and the formation of LIPSS has a high requirement for the surface roughness of the substrate, which is not conducive to large-scale applications. The coloration based on the high-temperature fusion self-smoothing mechanism of the oxide film has more advantages in color angle stability and color gamut range.

[0029] Currently, the mainstream oxide film coloring technology on the market is nanosecond laser coloring technology based on the master oscillator power amplifier (MOPA) architecture. Although this technology has significant advantages in terms of color angle stability and color gamut, it is limited by its relatively long pulse width, resulting in severe heat accumulation and easy thermal deformation of the substrate. Another single-pulse femtosecond laser coloring technology has the advantages of ultra-short pulse and low thermal impact, which theoretically can improve processing accuracy and color quality. However, in practice, the processed surface is prone to forming a rough laser-induced structure, resulting in a limited color gamut. Moreover, this technology has not yet achieved commercial application and is difficult to meet the requirements of industrial production.

[0030] According to an embodiment of this application, a method for coloring metal surfaces based on femtosecond lasers is provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0031] This embodiment provides a method for coloring metal surfaces based on femtosecond lasers. Figure 1 This is a flowchart of a metal surface coloring method based on femtosecond laser according to an embodiment of this application, as follows: Figure 1 As shown, the process includes the following steps:

[0032] Step 110: Match the target color in a preset two-dimensional color palette to obtain the processing parameter combination corresponding to the target color. The two-dimensional color palette generates and records different colors on the metal surface by changing the general parameters of laser processing and the number of sub-pulses in each pulse train.

[0033] Step 120: Based on the combination of processing parameters, use a femtosecond laser to perform surface coloring on the target metal.

[0034] The femtosecond laser-based metal surface coloring method provided in this embodiment combines the characteristics of common lasers and improves upon single-pulse femtosecond laser coloring technology by introducing pulse train technology. Specifically, the number of sub-pulses in each emitted pulse train is introduced as a new processing parameter.

[0035] like Figure 2 As shown in (a), in the prior art, a laser emits laser light periodically based on a fixed operating frequency during operation. Within each pulse cycle, only one laser pulse is emitted for laser surface processing. This embodiment proposes, as... Figure 2(b) is shown, by modulation, so that the laser no longer emits only one laser beam in each pulse period, but emits a group of pulse trains, and the pulse train includes a plurality of sub-pulses, and the number is equal to the parameter of the number of sub-pulses in each emitted pulse train. For example, if the parameter of the number of sub-pulses in the processing parameter combination is 4, then the laser works, and in each pulse period, four laser pulses are emitted, that is Figure 2 Examples in (b) are shown.

[0036] It should be noted that the present application involves two kinds of "pulse periods", the first is used to describe the interval between different pulse trains, that is, "the laser will only emit a group of pulse trains in each pulse period", which is referred to as "large pulse period" hereinafter; the other is used to describe the interval between different sub-pulses in the same pulse train, that is, "the laser will only emit one sub-pulse in each pulse period", which is referred to as "small pulse period" hereinafter. In addition, if "pulse period" is not explicitly described in the following, it can also be judged whether it represents a large pulse period or a small pulse period in combination with the context.

[0037] The introduction of the new parameter will affect the final generated color, so in practical application, the relationship between a plurality of processing parameter combinations and generated colors needs to be determined in advance, so that when needed, the specific value selected as the parameter of laser processing can be quickly determined. The present embodiment proposes to use a two-dimensional color palette as a carrier to store the relationship between a plurality of processing parameter combinations and generated colors.

[0038] When receiving an instruction to draw a target color on a target metal surface, the processing parameter combination corresponding to the target color is selected from the color palette, and the laser works with the processing parameter combination to generate corresponding femtosecond laser to color the surface of the target metal.

[0039] The essence of introducing a pulse train composed of a plurality of sub-pulses for processing in a large pulse period is actually to reduce the interval time between two adjacent pulse lasers. The method proposed in the present embodiment does not need to replace the laser with a shorter interval, but only needs to adjust the parameters or make a small modification based on the existing laser, and the number of pulses in the large pulse period can be increased by pulse trains.

[0040] Due to the low heat-affected feature of the existing single-pulse femtosecond laser coloring technology, reducing the interval time between two sub-pulses can reasonably control the heat accumulation of the metal surface, and further affect the generation of the microstructure. Moderate heat accumulation can promote the mutual fusion between the oxide ridge structures generated on the metal surface, reduce the roughness of the metal surface, thereby expanding the color gamut of coloring and achieving better coloring effect. From the analysis of the HSV color space, the present method can effectively improve the saturation and brightness of the generated color.

[0041] In practical applications, it can be required to draw a target pattern with multiple target colors on a metal surface. In this case, the method described in the embodiment can be performed for different color blocks in the target pattern. That is, for each color block, the general processing parameters corresponding to the target color of the color block are filled into the laser processing system to color the metal surface. Finally, a target pattern with a smooth surface, no thermal deformation and a wide color gamut is obtained.

[0042] The second embodiment of the present application further defines the method of coloring the metal surface based on femtosecond laser in the first embodiment in more detail and specifically. Part or all of the technical features in the second embodiment can be combined, replaced, etc. with the first embodiment, so as to obtain more kinds of feasible methods of coloring the metal surface based on femtosecond laser.

[0043] The method of coloring the metal surface based on femtosecond laser in the second embodiment of the present application is described in detail as follows:

[0044] Optionally, the preset two-dimensional color palette is pre-generated in the following manner: obtaining general parameters of laser processing and determining a variable parameter in the general parameters, the general parameters including at least one of single pulse energy, pulse width, repetition frequency, line spacing and scanning speed; using the laser, coloring the metal surface by keeping the general parameters except the variable parameter unchanged and continuously changing the variable parameter and the number of sub-pulses in each emitted pulse train, and establishing the preset two-dimensional color palette, in which the corresponding relationship between the color generated and the processing parameter combination composed of different general parameters and the number of sub-pulses in each emitted pulse train is recorded.

[0045] The embodiment further defines the generation manner of the preset two-dimensional color palette. Two parameters in the two-dimensional color palette should be used as dimensions. It has been determined that one of the dimensions is the number of sub-pulses in each emitted pulse train, and the other parameter can be selected from the general parameters of laser processing.

[0046] Referring to the method of obtaining color corresponding parameters in the prior art, the embodiment proposes that the general parameters of laser processing can include at least one of single pulse energy, pulse width, repetition frequency, line spacing and scanning speed, and one of them is selected as a variable parameter. In practical applications, the variable parameter can be selected according to actual needs. Generally, for the purpose of expanding the generated color range, a general parameter with a greater degree of influence on the generated color can be selected as the variable parameter, such as single pulse energy; or for the purpose of generating a more refined color palette, a general parameter with a greater degree of influence on the generated color can be selected as the variable parameter, so that the color difference between the matched color and the target color will be smaller when the generated color palette is matched with the target color.

[0047] When the palette is obtained, the laser is controlled to surface color the metal with a set of preset general parameters and the number of sub-pulses in each pulse train of each emission, and the set of data and the colors generated by the set of data are recorded in the palette. Then, a variable parameter in the general parameters or the number of sub-pulses is adjusted, a new set of general parameters and the number of sub-pulses in each pulse train of each emission is obtained, and the metal is surface colored, and the new set of data and the colors generated by the new set of data are also recorded in the palette. The adjustment method can be determined according to actual needs, for example, setting an upper limit and a lower limit of the range, starting from the lower limit of the range, adjusting the parameter at a fixed step until the parameter reaches the upper limit of the range, for example, setting the number of sub-pulses from 1, increasing by 1 each time, and the upper limit is 10.

[0048] The variable parameter and the number of sub-pulses in each pulse train of each emission are continuously changed to surface color the metal until the amount of data in the two-dimensional palette meets the requirements or the parameter reaches the boundary of the adjustment range and cannot be adjusted, that is, the preset two-dimensional palette is generated.

[0049] It should be noted that different metal atoms and interatomic structures are different, and the metallic properties and the difficulty of processing the metal surface are also different. In this embodiment, the metal used to generate the two-dimensional palette is the same as the target metal, and the two-dimensional palette of different types of metals cannot be mixed.

[0050] Optionally, the general parameters of laser processing are obtained, and a variable parameter is determined in the general parameters, including: under the conditions of fixed single pulse energy, fixed pulse width, and fixed repetition frequency, continuously changing the line spacing and the scanning speed to surface color the metal and recording, obtaining a general two-dimensional palette; under the conditions of fixed single pulse energy and fixed pulse width, continuously changing the repetition frequency to surface color the metal and recording, obtaining a general three-dimensional palette; under the condition of fixed single pulse energy, continuously changing the pulse width to surface color the metal and recording, obtaining a general four-dimensional palette; continuously changing the single pulse energy to surface color the metal and recording, obtaining a general five-dimensional palette; and selecting a variable parameter according to the general five-dimensional palette and determining the fixed value of the general parameter except the variable parameter.

[0051] This embodiment proposes a method for determining the variable parameter. Specifically, by the parameter traversal method, the relationship between single pulse energy, pulse width, repetition frequency, line spacing, and scanning speed and the generated color is systematically explored, and a five-dimensional palette is formed.

[0052] Based on the above steps, we can intuitively judge the influence of each general parameter on the generated color from the obtained five-dimensional palette. For example, the influence of the different processing parameters used by two adjacent colors on the generated color can be quantified by calculating the difference between the RGB values of the two adjacent colors in the palette.

[0053] Then, the parameter with the most potential, which is most likely to meet the actual demand (such as the demand for expanding the color gamut range or providing fine color selection, etc.), is selected as the variable parameter.

[0054] Optionally, the variable parameter is the scanning speed; the metal surface is colored by keeping the general parameters unchanged except the variable parameter, continuously changing the variable parameter and the number of sub-pulses in the pulse train of each emission, including: keeping the general parameters unchanged except the variable parameter, setting the initial value of the number of sub-pulses in the pulse train of each emission to one and gradually increasing it, setting the scanning speed to the product of the initial scanning speed and the number of sub-pulses, and coloring the metal surface.

[0055] The embodiment further limits the parameter adjustment mode of the two-dimensional color palette when the variable parameter is the scanning speed. Among them, the embodiment hopes to further improve the saturation and brightness of the generated color on the basis of the prior art, but does not want to have too exaggerated effects on the generated color, such as changing red to blue, etc.

[0056] Based on the above requirements, if the scanning speed does not change and only the number of sub-pulses in the pulse train of each emission is increased, the number of pulses received per unit area will be greatly increased, which will have a greater impact on the generation of color. Therefore, the embodiment proposes that the scanning speed is v, the number of sub-pulses is n, and the initial scanning speed or the scanning speed when the number of sub-pulses n=1 is v1, then the scanning speed is the product of the initial scanning speed and the number of sub-pulses, that is, v=n*v1.

[0057] In the embodiment, the lower limit of the number of sub-pulses can be 1, and the upper limit of the number of sub-pulses can be 10.

[0058] As shown in Figure 3 , Figure 3 (a) is the working condition of the laser when the number of sub-pulses is equal to 1, and the scanning speed is v1; Figure 3 (b) is the working condition of the laser when the number of sub-pulses is equal to 5, and the scanning speed is 5v1. The same proportional increase of the scanning speed and the number of sub-pulses can ensure that the number of laser pulses received per unit area is unchanged. As shown by the dashed boxes in Figure 3 (a) and Figure 3 (b), the areas scanned by the two dashed boxes and the number of pulses received per unit area in the scanned area are the same. When n=1, it is slow, consumes a lot of time, and needs to consume more time; when n=5, it is fast, consumes less time, and the pulse spacing is small, which saves time and also improves the saturation and brightness of the color.

[0059] In summary, the embodiment takes the scanning speed as a variable parameter to obtain a two-dimensional color palette with higher saturation and brightness compared to the prior art.

[0060] Optionally, according to the matching of the target color in the preset two-dimensional color palette, the processing parameter combination corresponding to the target color is obtained, including: obtaining the target color; calculating the Euclidean distance of the target color and each color in the preset two-dimensional color palette in the RGB color space, and taking the processing parameter combination corresponding to the color with the shortest Euclidean distance in the calculation result as the processing parameter combination corresponding to the target color.

[0061] In actual application, there may be a case that there is no color in the color palette strictly corresponding to the target color. The embodiment provides a method for obtaining the color most matching the target color from the color palette to obtain the most suitable processing parameter combination in this case.

[0062] Specifically, the Euclidean distance of the target color and each color in the two-dimensional parameter color palette in the RGB color space can be calculated, and the calculation formula of the Euclidean distance is:

[0063]

[0064] 、 and represent the RGB value of the target color color; 、 and represent the RGB value of the jth color in the color palette.

[0065] The above calculation is performed on each color in the color palette, and the processing parameter combination corresponding to the color with the shortest Euclidean distance in the calculation result is taken as the processing parameter combination corresponding to the target color.

[0066] In actual application, for the case of drawing a target pattern including multiple target colors, the above method can be performed on each color block in the target pattern.

[0067] Optionally, according to the processing parameter combination, the target metal is surface colored using a femtosecond laser, including: setting the femtosecond laser to emit a group of pulse trains every first preset time length, setting the interval between different sub-pulses in each pulse train to be a second preset time length, and setting other processing parameters of the laser to be the general parameters of the processing parameter combination; using a scanning system to focus the femtosecond laser to the target metal surface for processing.

[0068] The embodiment further limits the setting method of the processing parameter combination.

[0069] Specifically, in the prior art, the large pulse period of the laser is generally a fixed parameter and is much larger than the duration of a single pulse. For example Figure 3 As shown in (a), the duration of a single pulse only accounts for a small part of the entire pulse period. If the number of pulses is increased, how to control the distribution of the remaining pulses in the remaining time within the large pulse period is a problem to be solved.

[0070] The embodiment provides that the large pulse period is set as a first preset time length and the small pulse period is set as a second preset time length, i.e., the laser regularly and periodically emits a plurality of sub-pulses with the second preset time length as an interval in one large pulse period, and the time difference between any two adjacent sub-pulses is equal to the second preset time length. All the sub-pulses in one large pulse period are regularly and equally spaced.

[0071] The value of the first preset time length is related to the working parameters of the laser itself. The value of the second preset time length is not only related to the parameters of the laser, but also needs to consider the influence of heat accumulation on the coloring of the metal surface under different numbers of pulses, so as to set a reasonable value to avoid excessive heat accumulation between multiple pulses and surface deformation, and avoid too long pulse interval and the inability to affect the generation of microstructures.

[0072] Optionally, the interval between different pulse strings is microsecond-level, the target metal is titanium, and the interval between different sub-pulses in each pulse string is nanosecond-level.

[0073] The embodiment provides a specific implementation mode of the metal surface coloring method of the femtosecond laser. Specifically, the interval between different pulse strings, i.e., the large pulse period, is microsecond-level. For example, the large pulse period of a 400 kHz laser is 2.5 microseconds. The period of the sub-pulses in the pulse string is 40 MHz, and the small pulse period is 25 nanoseconds.

[0074] The target metal in the embodiment can be titanium. Titanium metal has been widely used in the fields of aerospace, biological medicine, high-end consumer goods and the like due to its high strength, low density, excellent corrosion resistance, good antibacterial property and excellent biocompatibility. The metal surface coloring method based on the femtosecond laser in the embodiment can be applied to titanium as thin as 0.3 mm without causing thermal deformation.

[0075] The embodiment further provides that the interval between different sub-pulses in the same pulse period, i.e., the small pulse period, is nanosecond-level. For example, the period of the sub-pulses in the pulse string is 40 MHz, and the period is 25 ns. The nanosecond-level interval can give the metal surface a certain cooling time, so that the metal surface has moderate heat accumulation and does not deform.

[0076] Next, the parameters are exemplified with a laser with a single pulse energy of 80 mJ / cm2, a pulse width of 371 fs, a repetition frequency of 400 kHz, a line spacing determined as 0.05 mm, and a scanning speed determined as 20 n to 160 n mm / s, and the target metal is titanium. The specific implementation of the method for coloring a metal surface based on a femtosecond laser described in the above embodiment is explained.

[0077] As shown in Figure 4 , the changes in the microstructure of the titanium surface are shown based on the above parameters when the number of sub-pulses is increased. (a) (b) (c) (d) correspond to the optical microscope photos of the structural color patterns with the number of sub-pulses being 1, 2, 5, and 10, respectively. When the number of sub-pulses is 1, it is single pulse processing, and the processed surface has a rough periodic grating structure, which macroscopically shows narrow hue, low brightness, low saturation, and narrow color gamut range. With the increasing number of sub-pulses, the original rough structure slowly melts and self-flattens due to heat accumulation, and macroscopically forms a surface feature with wide hue, high brightness, high saturation, and wide color gamut range.

[0078] The preset two-dimensional color palette used based on the above parameters is shown in Figure 5 .

[0079] In actual application, the process based on the above parameters is as follows: a preset image is obtained, which can be a cartoon pattern or a small daisy pattern. According to the different color blocks of the pattern, a closest color is selected from the preset color palette, and the processing parameters corresponding to the color are set in the laser processing system. The contours of each color block in the pattern are identified, and each color block is filled according to the preset line spacing, and the filling line is the actual laser processing route. The femtosecond pulse laser is focused on the target metal such as a titanium cup or a titanium metal sheet by using a scanning galvanometer system, and the preset image with no thermal deformation and wide color gamut is processed on the titanium cup or the titanium metal sheet according to the preset processing parameters and the laser processing route. According to the comparison, compared with the prior art using a single pulse femtosecond laser, the color saturation S of the pattern obtained by the method in the embodiment can be increased to 0.5, the lightness V can be increased to 60, and the thermal deformation is less than 50 μm, which is less than the original flatness of the pure titanium substrate. Compared with the pattern processed by a nanosecond laser, the color gamut can almost reach the level of the nanosecond laser, and the thermal deformation is far lower than 1.9 mm of the nanosecond laser. The processing result is shown in Figure 6 .

[0080] The third embodiment of the present application also proposes a device for coloring a metal surface based on a femtosecond laser, as shown in Figure 7 , the device comprises:

[0081] The matching module 710 is configured to match the target color in a preset two-dimensional color palette to obtain a processing parameter combination corresponding to the target color, wherein the two-dimensional color palette is generated by changing general parameters of laser processing and the number of sub-pulses in each emitted pulse train to generate different colors on a metal surface and record the different colors.

[0082] The processing module 720 is configured to use femtosecond laser to perform surface coloring on the target metal according to the processing parameter combination.

[0083] Further function descriptions of the above modules and units are the same as those of the corresponding embodiments, and will not be described here.

[0084] The femtosecond laser-based metal surface coloring device in the embodiment is presented in the form of functional units. The units herein refer to ASIC (Application Specific Integrated Circuit) circuits, processors and memories executing one or more software or fixed programs, and / or other devices that can provide the above functions.

[0085] Please refer to Figure 8 , Figure 8 is a structural schematic diagram of a computer device provided by the embodiment of the present application, as Figure 8 shown, the computer device includes one or more processors 810, a memory 820, and an interface for connecting various components, including a high-speed interface and a low-speed interface. Various components communicate and connect with each other using different buses, and can be installed on a common mainboard or in other ways as needed. The processor can process instructions executed in the computer device, including instructions stored in the memory or memory to display GUI graphics information on an external input / output device (such as a display device coupled to the interface). In some optional embodiments, if necessary, multiple processors and / or multiple buses can be used with multiple memories and multiple memories. Similarly, multiple computer devices can be connected, each providing part of the necessary operations (for example, as a server array, a group of blade servers, or a multi-processor system). Figure 8 In the embodiment, the processor 810 is taken as an example.

[0086] The processor 810 can be a central processor, a network processor, or a combination thereof. The processor 810 can further include a hardware chip. The hardware chip can be an application specific integrated circuit, a programmable logic device, or a combination thereof. The programmable logic device can be a complex programmable logic device, a field programmable logic gate array, a general array logic, or any combination thereof.

[0087] The memory 820 stores instructions that are executable by the at least one processor 810, so that the at least one processor 810 performs the method implemented by the above-mentioned embodiments.

[0088] The memory 820 can include a program storage area and a data storage area. The program storage area can store an operating system, application programs required by at least one function, and the like. The data storage area can store data created according to the use of the computer device, and the like. In addition, the memory 820 can include a high-speed random access memory, and can further include a non-transitory memory such as at least one of a disk storage device, a flash memory device, or other non-transitory solid-state memory device. In some optional embodiments, the memory 820 can optionally include a memory disposed remotely with respect to the processor 810, and these remote memories can be connected to the computer device through a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and a combination thereof.

[0089] The memory 820 can include a volatile memory such as a random access memory, and can also include a non-volatile memory such as a flash memory, a hard disk, or a solid-state disk. The memory 820 can also include a combination of the above-mentioned kinds of memories.

[0090] The embodiment of the present application provides a computer program product, which includes computer instructions stored in a computer readable storage medium. The processor of the computer device reads the computer instructions from the computer readable storage medium, and the processor executes the computer instructions, so that the computer device executes the method of any embodiment of the present application.

[0091] Although the embodiments of the present application are described in conjunction with the accompanying drawings, various modifications and changes can be made by those skilled in the art without departing from the spirit and scope of the present application, and such modifications and changes fall within the scope defined by the appended claims.

[0092] It can be understood that, before using the technical solutions disclosed in the embodiments of the present disclosure, the type of personal information involved in the present disclosure, the use range, the use scenario, and the like should be informed to the user and the authorization of the user should be obtained through appropriate means according to relevant laws and regulations.

[0093] For example, in response to receiving the active request of the user, prompt information is sent to the user to explicitly prompt the user that the operation requested to be executed will need to obtain and use the personal information of the user. Thus, the user can voluntarily choose whether to provide the personal information to the software or hardware such as an electronic device, an application program, a server, or a storage medium that executes the operation of the technical solutions of the present disclosure according to the prompt information.

[0094] As an optional but non-limiting implementation, in response to receiving the active request of the user, the manner of sending the prompt information to the user may be, for example, a pop-up window manner, and the prompt information may be presented in the pop-up window in the form of text. In addition, the pop-up window may also carry a selection control for the user to select "agree" or "disagree" to provide the personal information to the electronic device.

[0095] It can be understood that the above notification and user authorization obtaining process is only illustrative and does not limit the implementation of the present disclosure, and other manners meeting the relevant laws and regulations can also be applied to the implementation of the present disclosure.

[0096] It can be understood that the data involved in the technical solution (including but not limited to the data itself, the acquisition or use of the data) should comply with the requirements of the relevant laws and regulations and the relevant provisions.

[0097] It can be understood that in the specific embodiments of the present application, data related to user information, location information, navigation data, etc. is involved, and when the above embodiments are applied to specific products or technologies, the user's permission or consent needs to be obtained, and the collection, use and processing of the related data need to comply with the relevant laws and regulations and standards of the relevant countries and regions.

[0098] The apparatus, computer device or computer program product illustrated in the above embodiments can be specifically implemented by a computer chip or entity, or by a product with certain functions. A typical implementation device is a computer. Specifically, the computer may, for example, be a personal computer, a laptop computer, a cellular phone, a camera phone, a smart phone, a personal digital assistant, a media player, a navigation device, an email device, a game console, a tablet computer, a wearable device, or a combination of any of these devices.

[0099] For the convenience of description, the above apparatus is described as various units divided by functions for description. Of course, the functions of each unit can be implemented in the same or multiple software and / or hardware in the implementation of the present application.

[0100] Those skilled in the art will understand that the embodiments of the present application can be provided as a method, apparatus, computer device or computer program product. Therefore, the present application can take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0101] The present application is described in reference to the flowcharts and / or block diagrams of the methods, apparatuses, computer devices or computer program products according to the embodiments of the present application. It should be understood that each flow and / or block in the flowcharts and / or block diagrams, and the combination of flows and / or blocks in the flowcharts and / or block diagrams can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing devices generate a device that implements the functions specified in the flowcharts and / or block diagrams. Figure 1 one or more flows and / or blocks. Figure 1 one or more flows and / or blocks.

[0102] These computer program instructions can also be stored in a computer readable memory that can direct the computer or other programmable data processing devices to work in a specific manner, so that the instructions stored in the computer readable memory produce a manufactured product including instruction devices that implement the functions specified in the flowcharts and / or block diagrams. Figure 1 one or more flows and / or blocks. Figure 1 one or more flows and / or blocks.

[0103] These computer program instructions can also be loaded into a computer or other programmable data processing device, so that a series of operation steps are performed on the computer or other programmable data processing device to produce a computer implemented process, so that the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in the flowcharts and / or block diagrams. Figure 1 one or more flows and / or blocks. Figure 1 one or more flows and / or blocks.

[0104] It should also be noted that the terms "comprising", "including", or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or other elements inherent in such a process, method, article or device. Without more limitations, the element defined by the statement "comprising a" does not exclude the presence of additional identical elements in the process, method, article or device including the element.

[0105] Each embodiment in the specification is described in a progressive manner, and the same or similar parts between each embodiment can be referred to each other, and each embodiment focuses on the difference from other embodiments. In particular, for the device, computer device or computer program product embodiments, since they are basically similar to the method embodiments, the description is relatively simple, and the relevant parts can be referred to the part of the method embodiment.

[0106] The above merely provides an example of the present application, but is not intended to limit the present application. The present application can have various modifications and changes for those skilled in the art. Any modification, equivalent replacement, improvement, etc. within the spirit and principle of the present application shall be included in the scope of claims of the present application.

[0107] Although the embodiments of the present application are described in conjunction with the accompanying drawings, various modifications and changes can be made by those skilled in the art without departing from the spirit and scope of the present application, and such modifications and changes shall fall within the scope of the appended claims.

Claims

1. A method for coloring metal surfaces based on femtosecond lasers, characterized in that, The method includes: The target color is matched in a preset two-dimensional color palette to obtain the processing parameter combination corresponding to the target color. The two-dimensional color palette is generated and recorded by changing the general parameters of laser processing and the number of sub-pulses in each pulse train. Based on the combination of processing parameters, a femtosecond laser is used to color the surface of the target metal. The preset two-dimensional color palette is generated in advance in the following manner: Obtain the general parameters of the laser processing and determine a variable parameter from the general parameters. The general parameters include at least one of single pulse energy, pulse width, repetition frequency, line spacing and scanning speed. Using a laser, the metal surface is colored by continuously changing the variable parameters and the number of sub-pulses in each pulse train while keeping the general parameters other than the variable parameters constant. A preset two-dimensional color palette is established, in which the correspondence between the processing parameter combinations composed of different general parameters and the number of sub-pulses in each pulse train and the generated colors is recorded.

2. The method according to claim 1, characterized in that, The step of obtaining the general parameters of the laser processing and determining a variable parameter from the general parameters includes: Under fixed single pulse energy, fixed pulse width, and fixed repetition frequency, the line spacing and scanning speed are continuously changed to perform metal surface coloring and record the results, thereby obtaining a universal two-dimensional color palette. With fixed single pulse energy and fixed pulse width, the repetition frequency was continuously changed to color the metal surface and the results were recorded to obtain a general three-dimensional color palette; By continuously changing the pulse width under a fixed single pulse energy, the coloring of the metal surface is recorded, and a universal four-dimensional color palette is obtained. By continuously varying the energy of a single pulse to color the metal surface and recording the results, a universal five-dimensional color palette can be obtained. Select one of the variable parameters according to the general five-dimensional color palette and determine the fixed values ​​of the general parameters other than the variable parameter.

3. The method according to claim 1, characterized in that, The variable parameter is the scanning speed; The process of coloring the metal surface by keeping all general parameters except the variable parameters constant and continuously changing the variable parameters and the number of sub-pulses in each emitted pulse train includes: Keeping all general parameters except the variable parameters unchanged, the initial value of the number of sub-pulses in each transmitted pulse train is set and gradually increased, and the scanning speed is set to the product of the initial scanning speed and the number of sub-pulses, and then the metal surface is colored.

4. The method according to claim 1, characterized in that, The step of matching the target color in a preset two-dimensional color palette to obtain the processing parameter combination corresponding to the target color includes: Obtain the target color; Calculate the Euclidean distance between the target color and each color in the preset two-dimensional color palette in the RGB color space, and use the processing parameter combination corresponding to the color with the shortest Euclidean distance in the calculation results as the processing parameter combination corresponding to the target color.

5. The method according to claim 1, characterized in that, The step of using a femtosecond laser to color the surface of the target metal according to the processing parameter combination includes: The femtosecond laser is configured to emit a pulse train every first preset duration, the interval between different sub-pulses within each pulse train is set to a second preset duration, and the other processing parameters of the laser are set to general parameters of the processing parameter combination. The femtosecond laser is focused onto the target metal surface using a scanning system for processing.

6. The method according to claim 1, characterized in that, The interval between different pulse trains is on the order of microseconds, the target metal is titanium, and the interval between different sub-pulses within each pulse train is on the order of nanoseconds.

7. A metal surface coloring device based on femtosecond laser, characterized in that, The device includes: The matching module is used to match the target color in a preset two-dimensional color palette to obtain the processing parameter combination corresponding to the target color. The two-dimensional color palette is generated and recorded on the metal surface by changing the general parameters of laser processing and the number of sub-pulses in each pulse train. The processing module is used to perform surface coloring on the target metal using a femtosecond laser according to the processing parameter combination; The preset two-dimensional color palette is generated in advance in the following manner: Obtain the general parameters of the laser processing and determine a variable parameter from the general parameters. The general parameters include at least one of single pulse energy, pulse width, repetition frequency, line spacing and scanning speed. Using a laser, the metal surface is colored by continuously changing the variable parameters and the number of sub-pulses in each pulse train while keeping the general parameters other than the variable parameters constant. A preset two-dimensional color palette is established, in which the correspondence between the processing parameter combinations composed of different general parameters and the number of sub-pulses in each pulse train and the generated colors is recorded.

8. A computer device, characterized in that, include: A memory and a processor are interconnected, the memory storing computer instructions, and the processor executing the computer instructions to perform the femtosecond laser-based metal surface coloring method according to any one of claims 1 to 6.

9. A computer program product, characterized in that, Includes computer instructions for causing a computer to perform the femtosecond laser-based metal surface coloring method according to any one of claims 1 to 6.

Images