Method for producing 3d ultra-precision optical texture on glass surface

Abstract

The application discloses a method for preparing 3D ultra-precision optical texture on a glass surface and belongs to the technical field of glass etching. According to the method, an appearance effect drawing is first drawn, the appearance effect drawing is converted into a pixel gray scale drawing, a grating unit drawing is embedded into each pixel point, and the grating unit drawing is angle-rotated according to the gray scale value of the pixel point; after all the pixel points are embedded with the grating unit drawing, a grating dot array vector drawing is exported. Then, a mask made of the grating dot array vector drawing is placed in a mask exposure machine, the glass is exposed and developed, and the glass is etched by using an etching liquid. According to the method, a more precise appearance effect drawing can be designed, the grating unit can provide uniform line width and line spacing, the precision control in the subsequent etching stage is facilitated, the precision of the glass etching structure is greatly improved, and the purpose of preparing a more precise optical texture pattern is achieved.

Description

Technical Field

[0001] This invention relates to the field of glass etching technology, and in particular to a method for preparing 3D ultra-precision optical textures on glass surfaces. Background Technology

[0002] The glass surfaces of the back and front covers of mobile phones, tablets, and smart wearable electronic products are usually decorated with various textured patterns. In existing technologies, vector graphics software is typically used to directly draw the desired textured pattern. Photoresist is then sprayed onto the glass surface, exposed using a laser direct-write lithography machine, and developed to obtain the photoresist pattern corresponding to the drawing. Next, hydrofluoric acid or other acidic solutions are used to liquid-polish the glass with the photoresist. After etching, cleaning and strengthening are performed to obtain the finished glass etched product with the aforementioned textured pattern.

[0003] like Figure 1 As shown, an appearance rendering is created using vector graphics software. Then, a line structure diagram is drawn along the texture direction based on the appearance rendering. This line structure diagram is then used for exposure on a laser direct-write lithography machine. Directly drawing the line structure diagram using vector graphics software is limited by software capabilities and drawing formats; only large-scale patterns such as lines, circles, and matrices can be drawn. Figure 1 As shown in the schematic diagram of the line structure, the line structure is uneven, with the highest precision being several hundred micrometers. This precision poses a control risk to the subsequent etching stage. The structural resolution is not high enough to completely reproduce the structure of the drawing. In addition, the use of a laser direct-write lithography machine will result in laser traces left on the photoresist, which manifests as a large number of horizontal and vertical lines on the entire glass surface, affecting the appearance of the etched product. Figures 2-4 For use Figure 1 The drawing method shown is used to create an appearance rendering. The appearance rendering is then used to expose the final glass product on a laser direct-write lithography machine. The lines and structures in the drawing are relatively simple, and the texture precision is not high.

[0004] Chinese patent document CN115713570A (hereinafter referred to as the prior art) discloses a method for generating gradient texture patterns, which converts a grayscale image of a gradient effect into a gradient grid image, giving it an editable vector block graphic. This method can only draw gradient effects, transforming a linear gradient effect from a pixelated image into a discrete vector graphic composed of small squares, thus reflecting the gradient effect through variations in grid density. The grid consists of uniform, identical small squares, and is either white or black, representing etched and protected areas respectively. Since the grid is not a raster unit, it lacks line width and spacing and does not rotate, belonging to the same 2D structure as line structures. (See attached prior art). Figure 3-4As shown, while a single grid can achieve a high degree of detail and uniformity, when multiple grids are connected, the uniformity deteriorates because grids are either black or white, and grids of the same color are connected together. This leads to difficulties in controlling the etching effect in the later stages. Limited by this drawing method, it is impossible to create highly flexible patterns. Furthermore, because it lacks a rotating raster structure, it cannot dynamically adjust the angle of light and shadow to obtain light and shadow patterns with variations in brightness and darkness. Therefore, it can only show a gradient trend, presenting a hazy effect. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a method for preparing 3D ultra-precision optical textures on glass surfaces, in view of the above-mentioned defects of the prior art.

[0006] To achieve the above objectives, the present invention provides a method for preparing 3D ultra-precision optical textures on a glass surface, the method comprising the following steps:

[0007] Step S1: Draw the appearance effect diagram of the 3D texture pattern;

[0008] Step S2: Based on the preset period value of the grating unit and the product size, the resolution of the appearance rendering is set and pixel segmentation is performed to convert the appearance rendering into a pixel grayscale image.

[0009] Step S3: Determine the line width and line spacing of the grating unit according to the preset period value of the grating unit, and design the grating structure accordingly, and draw the grating unit diagram in vector format.

[0010] Step S4: For each pixel position in the pixel grayscale image, embed a raster unit image, and rotate the embedded raster unit image according to the grayscale value of the pixel. After embedding all pixel positions of the pixel grayscale image into the rotated raster unit image, a raster dot matrix image is obtained. The raster dot matrix image is then exported as a raster dot matrix vector image.

[0011] Step S5: Place the photomask made of the grating dot vector image into the photomask exposure machine to expose and develop the glass;

[0012] Step S6: Use an etching solution to etch the glass to form a textured pattern.

[0013] Preferably, in step S2, the resolution is set and the pixels are segmented according to the rule that each pixel corresponds to one grating unit.

[0014] Preferably, step S3 further includes determining the linewidth and line spacing of the grating by combining the desired visual effect with the acid resistance of the photoresist.

[0015] Preferably, in step S4, rotating the embedded raster unit map according to the grayscale value of the pixel includes the following steps:

[0016] The preset angle C is determined based on the visual effect of the 3D texture pattern;

[0017] The preset angle C is divided into 256 equal parts, and the value of each part is taken as an angle component. The angle a of rotation of the raster unit map of each pixel is set to the gray value b of the current pixel multiplied by the angle component.

[0018]

[0019] The raster unit map of each pixel is rotated according to the set rotation angle.

[0020] Preferably, the preset angle C is 90°.

[0021] Preferably, the preset angle C is 180°.

[0022] Preferably, in step S5, before exposing the glass, the method further includes: applying photoresist to the glass surface to be etched using a spraying machine, wherein the acid resistance of the photoresist is matched with the expected etching time, and the thickness of the photoresist layer needs to be adjusted according to the designed texture structure height.

[0023] Preferably, the photoresist is a positive photoresist.

[0024] Preferably, in step S6, by adjusting the concentration of the etching solution and the etching time, the etching solution can fully etch the glass in the downward direction while also etching it in the left and right directions, forming a 3D peak-shaped texture.

[0025] This invention provides a method for preparing 3D ultra-precise optical textures on glass surfaces. First, an appearance rendering is created, which is then converted into a pixel grayscale image. Next, a grating unit image is embedded into each pixel, and the grating unit image is rotated according to the grayscale value of that pixel. After all pixels are embedded in the grating unit image, it is exported as a grating dot matrix vector image. Then, a photomask made from the grating dot matrix vector image is placed in a photomask exposure machine to expose and develop the glass. Finally, an etching solution is used to etch the glass. Using this method, more precise appearance renderings can be designed. The grating units can provide uniform line width and spacing, facilitating precision control in subsequent etching stages, significantly improving the precision of the glass etching structure, and achieving high pattern fidelity, thereby realizing the goal of preparing more precise optical texture patterns. Attached Figure Description

[0026] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this invention, illustrate exemplary embodiments of the invention and are used to explain the invention, but do not constitute an undue limitation of the invention. In the drawings:

[0027] Figure 1 This is a schematic diagram illustrating the process of creating optical texture patterns using vector graphics software.

[0028] Figure 2-4 To apply optical texture patterns drawn by vector graphics software to images of glass products obtained by a laser direct-write lithography machine.

[0029] Figure 5 This is a schematic diagram illustrating the steps of a method for preparing 3D ultra-precision optical textures on a glass surface according to an embodiment of the present invention.

[0030] Figure 6 This is a schematic diagram of the optical texture pattern formation process provided in an embodiment of the present invention.

[0031] Figure 7 A schematic diagram of the glass etching process in the method for preparing optical texture patterns drawn using vector drawing software.

[0032] Figure 8 This is a schematic diagram of the glass etching process in the method for preparing 3D ultra-precision optical textures on a glass surface provided in an embodiment of the present invention.

[0033] Figure 9-11 Images of glass products obtained according to embodiments of the present invention. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0035] The general idea of ​​this invention is as follows: draw an appearance rendering, convert the appearance rendering into a pixel grayscale image, then embed a pre-designed raster unit image at the position of each pixel, and rotate the raster unit image according to the grayscale value of the current pixel to obtain a raster dot vector image. Import the raster dot vector image into a photomask exposure machine to expose and develop the glass, and then use an etching solution to etch the glass. By selecting a photoresist with appropriate acid resistance, adjusting the concentration of the etching solution, and controlling the etching time, etching occurs both downwards and to the left and right, producing a 3D peak structure surface.

[0036] The embodiments of the present invention will now be described in further detail with reference to the accompanying drawings. It should be understood that the embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the scope of the invention.

[0037] This invention is applicable to high-precision etching of texture patterns on glass surfaces.

[0038] like Figure 5 As shown, this embodiment of the invention provides a method for preparing 3D ultra-precision optical textures on a glass surface, the method comprising the following steps:

[0039] Step S1: Draw the appearance effect diagram of the 3D texture pattern;

[0040] The appearance renderings are created using drawing software. During the creation process, the aspect ratio of the image is designed according to the product dimensions. This invention does not restrict the specific drawing software or drawing format. The appearance renderings only need to produce a planar pattern that can be confirmed, no longer limited to simple graphics of large structures. This greatly increases the freedom of pattern design, allowing for pattern customization and fine adjustments, and producing high-precision biomimetic effect patterns. JPG, PNG, BMP, and other pixel-level drawings, vector graphics produced by CAD, AI, CDR, and other software, as well as 3D model drawings in STP and other formats can all be used as appearance renderings. This invention also does not limit the colors of the appearance renderings.

[0041] Step S2: Based on the preset period value of the grating unit and the product size, the appearance effect image is processed by resolution setting and pixel segmentation, with each pixel corresponding to a grating unit; the appearance effect image is then converted into a pixel grayscale image.

[0042] The period of the grating unit is determined by the linewidth and spacing of the grating. The photomask exposure machine has precision limitations when exposing patterns on the photomask, and the photoresist thickness on the glass is also limited. If the photoresist thickness is too large, the photoresist layer cannot be fully activated during exposure, and the photoresist corresponding to the exposed portion cannot be completely dissolved in the subsequent development process, affecting the subsequent etching effect. The ratio of photoresist thickness to grating linewidth is usually fixed; the photoresist thickness cannot be too large, and the linewidth cannot be too small. To ensure that glass etching proceeds downwards while simultaneously lateral etching occurs, forming a 3D peak surface, the linewidth and spacing usually need to be set according to a certain ratio. Therefore, the linewidth and spacing of the grating unit cannot be infinitely small, and thus the period of the grating unit cannot be infinitely small either. Furthermore, when the period of the grating unit is too small, for example, 10µm, visible light is completely scattered, turning into color, which may present an unintended visual effect. Therefore, the period of the grating unit needs to be set to a reasonable value. In this embodiment of the invention, commonly used values ​​for the grating unit period design are 40µm and 80µm. To obtain high-resolution texture patterns, a smaller period should be chosen for the raster units. For deeper etching depths, a larger period and linewidth should be chosen. In subsequent steps, a raster unit map is drawn based on the raster unit period and embedded into the pixel locations of the pixel grayscale image. Since the smallest pixel visible to the human eye is 100µm x 100µm, the raster unit period value must be less than 100µm to prevent the raster unit map from being visible to the naked eye. In practical applications, the maximum raster unit period is typically set to 80µm.

[0043] The period of a raster unit refers to the side length of a square raster unit vector image. Based on the product dimensions and a preset raster unit period value, the appearance image is divided into pixels. For example, if the product dimensions are 20cm x 15cm and the preset raster unit period value is 20µm, pixel division of the appearance image is equivalent to dividing the image into pixels of 20µm x 20µm each. Based on the product's length and width, the number of rows and columns of pixels is calculated, thus determining the pixel resolution. Next, the pixel-divided image is converted into a grayscale image. In practice, this pixel division and grayscale conversion can be achieved using drawing software such as Photoshop, Illustrator, and CorelDRAW, or through software coding.

[0044] Step S3: Determine the line width and line spacing of the grating unit according to the preset period value of the grating unit, and draw the grating unit diagram in vector format.

[0045] Given a preset period value for the grating unit, drawing a vector-format grating unit diagram requires first designing the grating structure, specifically the internal structure of the grating unit, including the number of lines, line width, and line spacing within each unit. Then, the vector-format grating structure unit diagram is drawn based on the line width and line spacing. The grating line width and spacing need to be determined by considering the desired visual effect and the acid resistance of the photoresist. For structures requiring a strong tactile feel and deep etching, the line width needs to be increased to protect the glass, allowing for a sufficiently long etching time to achieve the desired depth. If the photoresist's acid resistance is insufficient, the grating line width needs to be increased, i.e., increasing the protected area to ensure the etched surface shape. In the design, the line spacing is usually designed to be as small as possible. In this embodiment of the invention, limited by the precision of the photomask exposure machine, the minimum line spacing can be 10µm. For a 40µm grating unit period, the line spacing and line width are typically set to 10µm and 30µm, respectively; for an 80µm grating unit period, the line spacing and line width are typically set to 10µm and 70µm, respectively.

[0046] Whether the lines in the rendering are curved or not does not affect the parameter design of the grating. After converting the rendering into a grayscale pixel drawing, the grating structure is only filled for pixels. The texture trend has been drawn during the rendering design. Therefore, this method greatly expands the applicability of glass etching textures and can draw almost all types of patterns. Because the appearance design does not need to be limited by the etched structure, the grating unit replaces the original large structure, and the appearance design has a very high degree of freedom.

[0047] It should be noted that steps S3 and S1-2 are independent of each other. Step S3 can be placed after step S2 or before step S1.

[0048] Step S4: For each pixel position in the pixel grayscale image, a raster unit image is embedded, and the embedded raster unit image is rotated according to the grayscale value of the pixel. After all pixel positions in the pixel grayscale image are embedded in the rotated raster unit image, a raster dot matrix image is obtained. The raster dot matrix image is then exported as a raster dot matrix vector image.

[0049] Figure 6 This demonstrates how to convert an appearance rendering into a pixel grayscale image. Figure 6 The middle part is the "pattern appearance grayscale image"), then the pixel grayscale image ( Figure 6 The image in the middle ("pattern appearance grayscale image") is converted to a raster image. Figure 6 The process is shown in the "grating structure diagram".

[0050] The step of rotating the embedded raster unit map based on the grayscale value of the pixel includes the following steps:

[0051] The preset angle C is determined based on the visual effect of the 3D texture pattern;

[0052] The preset angle C is divided into 256 equal parts, and the value of each part is taken as an angle component. The angle a of rotation of the raster unit map of each pixel is set to the gray value b of the current pixel multiplied by the angle component.

[0053]

[0054] The raster unit map of each pixel is rotated according to the set rotation angle.

[0055] Because there are 256 possible values ​​for a commonly used 8-bit grayscale value, the preset angle C is divided into 256 equal parts, so that the rotation angle corresponds one-to-one with the grayscale value. In this embodiment of the invention, the preset angle C is usually set to 90° or 180°, where 90° corresponds to the case of one light ray incident and 180° corresponds to the case of two light rays incident. When the preset angle C is set to 90°, only one area of ​​the glass product is lit up under standard lighting. When the preset angle C is set to 180°, two symmetrical areas of the glass product are lit up under standard lighting. In practical applications, the preset angle C is selected according to the visual effect of the 3D texture pattern.

[0056] After embedding all pixels in the pixel grayscale image into a rotated raster unit image, a raster bitmap is obtained. Exporting the raster bitmap into a common vector format, such as DXF or DWG, yields a raster bitmap vector image.

[0057] In practice, the processing described in step S4 can be implemented using drawing software such as Photoshop, Illustrator, and CorelDRAW, or through software coding.

[0058] The rotation of the raster unit image based on the grayscale value of the pixel refers to rotating the raster unit around its own axis, giving the raster unit different viewing angles. Different viewing angles produce different visual effects of brightness and darkness, and different grayscale values ​​of the pixels also correspond to different visual effects of brightness and darkness. Therefore, by embedding raster units with different rotation angles into the corresponding pixels, a visual effect of brightness and darkness that is close to the original visual effect image can be obtained.

[0059] From a geometrical optics perspective, rotating grating units create varying degrees of brightness and shadow effects, primarily based on the principles of light refraction, reflection, and diffraction. A grating consists of many parallel lines or openings that diffract light rays, creating beams of light in multiple directions. When these beams intersect with the observer's line of sight or other surfaces, specific lighting effects are created. Rotating the grating alters the light's propagation path by changing the relative angle between the grating and the light rays, thus producing different brightness and shadow effects. These effects depend on the grating's physical structure, such as linewidth, line spacing, and the angle of rotation.

[0060] Step S5: Place the photomask made of the grating dot vector image into the photomask exposure machine to expose and develop the glass;

[0061] Before exposing the glass, the process includes applying photoresist to the glass surface to be etched using a spray coating machine. The acid resistance of the photoresist is matched to the expected etching time, and the thickness of the photoresist layer is adjusted according to the designed texture height. Using a spray coating machine can form a uniform photoresist film on the glass surface, which is beneficial for controlling the exposure energy. The acid resistance of the photoresist is measured by the rate at which it detaches from the etching solution. In this embodiment of the invention, a photoresist with strong acid resistance needs to be selected to prevent the photoresist from detaching before the etching is completed, leaving non-etched areas unprotected and corroded. If a photoresist with insufficient acid resistance is selected, a photoresist protection area needs to be added during the design phase to achieve the best possible etching effect, but this method limits the fineness of the structure and the appearance.

[0062] Photoresist is divided into positive and negative photoresist. When exposed to light of a specific wavelength, positive photoresist undergoes a chemical reaction in the illuminated area, allowing it to dissolve in the developer during subsequent development, thus exposing the underlying glass substrate for the next etching process. The main advantages of positive photoresist over negative photoresist are steeper pattern edges and higher resolution. Therefore, in this embodiment of the invention, positive photoresist is used to obtain a better appearance. Exposure is performed using positive photoresist, which corresponds to the line spacing of the grating. After development, the exposed portion dissolves, exposing the glass substrate corresponding to the grating line spacing. After exposure and development, the linewidth and line spacing of the grating can be measured using a microscope. Experiments show that, while ensuring visual quality, after exposure and development using a photomask exposure machine, the minimum period of the grating unit can be 20µm, and the minimum linewidth and line spacing can both be 10µm. Compared to existing technologies that involve drawing an appearance rendering using vector graphics software, then drawing a line structure diagram along the texture direction based on the appearance rendering, and finally using the line structure diagram for exposure on a laser direct-write lithography machine with a maximum precision of several hundred micrometers, this method significantly improves the precision of the pattern.

[0063] Compared to laser direct-write lithography, photomask exposure machines use photomasks created from grating dot vector graphics for non-contact exposure of glass. This eliminates the need for laser movement, preventing exposure marks on the glass and allowing for one-time formation of high-precision optical texture patterns. Furthermore, by creating photomasks from grating dot vector graphics and placing them in the photomask exposure machine, batch exposure of glass is possible. This significantly improves exposure efficiency compared to laser direct-write lithography, which requires laser movement and can only expose one piece of glass at a time.

[0064] Step S6: Etch the glass with an etching solution to form a textured pattern. By adjusting the concentration and etching time of the etching solution, the glass is etched downwards while also being etched to the left and right, forming a 3D peak-shaped texture.

[0065] In this embodiment of the invention, positive photoresist is used for exposure. After development, the exposed portion dissolves, exposing the glass substrate corresponding to the grating line spacing. The etching solution then etches the substrate from the line spacing position.

[0066] In this embodiment of the invention, a positive photoresist with strong acid resistance is selected, and the etching solution is a hydrofluoric acid solution. Adjusting the concentration of the etching solution slows down the etching rate, allowing the glass to etch downwards along the line spacing while simultaneously lateral etching occurs on the adjacent linewidth. The concentration of the etching solution needs to be adjusted according to the linewidth of the grating unit; a larger linewidth requires a higher concentration, and a smaller linewidth requires a lower concentration.

[0067] In this embodiment of the invention, experiments showed that with a photoresist thickness of 6 μm, a line spacing of 20 μm, a line width of 30 μm, and a 2.2% concentration of hydrofluoric acid etching solution, a 3D spike structure with a size of approximately 20*30 μm can be obtained.

[0068] Figure 7 This diagram illustrates the glass etching process in an optical texture preparation method using vector graphics software to create optical texture patterns. The method of using line structures drawn with vector graphics software for exposure is limited by software capabilities and drawing formats. It can only create large-scale patterns, such as simple lines, circles, and matrices. Furthermore, it requires designing line widths and spacings of varying sizes based on the shape of the visual rendering. This results in uneven line widths and spacing, low precision, and line widths typically in the hundreds of micrometers, which hinders the control of subsequent etching effects. The overall etching effect is difficult to control, and the final result cannot reproduce the drawing structure. The side etching effect is not significant relative to the line width, thus yielding an effect like... Figure 7 The texture of the 2D surface shown.

[0069] Figure 8This is a schematic diagram of the glass etching process in the method for preparing 3D ultra-precision optical textures on a glass surface provided in an embodiment of the present invention. First, an appearance rendering is drawn, then converted into a grating dot matrix vector image for exposure. The appearance rendering can be designed into a more refined texture pattern. The grating dot matrix vector image is composed of grating units, each with linewidth and spacing. The rotation angles of each grating unit are different, while the linewidth and spacing are consistent. Unlike Chinese patent document CN115713570A, where multiple grids connected together lead to a decrease in overall uniformity, the grating dot matrix vector image, composed of numerous uniform grating units, can still maintain uniformity. This uniformity is beneficial for controlling the subsequent etching effect. The grating units have small periods and high precision, with linewidths typically in the range of several μm to tens of μm, resulting in a more pronounced side etching effect, thus enabling the production of... Figure 8 The 3D spike-shaped surface texture shown can increase the transparency and brightness of the texture effect, improve the consistency of the etched texture structure, and thus improve the overall product yield.

[0070] The above only mentions the key steps in preparing 3D ultra-precision optical textures on glass surfaces. The complete production process is described below:

[0071] (1) Design the required appearance renderings and raster unit vector graphics, and convert the appearance renderings into raster dot vector graphics.

[0072] (2) Cutting the glass, applying protective oil to the non-etched surface of the glass, and cleaning the glass:

[0073] The glass substrate is cut to the required size using a CNC machine tool, and the cut glass is then polished to increase the edge strength. After removing the protective oil applied during transportation, hot-pressing, and polishing, an acid-resistant protective oil is sprayed onto the non-etched surfaces. The acid-resistant protective oil consists of: 40-70% resin, 20-50% filler, 10-20% diluent, and 1-10% additives.

[0074] Then, the glass is washed with ultrasonic water. The alkaline solution removes oil, dirt, and stubborn foreign matter from the glass surface under ultrasonic vibration. The glass surface is then rinsed and soaked in water and slowly pulled to make it even cleaner.

[0075] (3) Spray photoresist onto the glass and pre-bake the photoresist:

[0076] Positive photoresist is sprayed onto the etched surface of the glass using a spray gun. The photoresist is atomized by the spray gun to form a uniform liquid film on the glass surface. Positive photoresist with higher resolution is selected, and high acid resistance photoresist is required. The thickness of the photoresist needs to be dynamically adjusted according to the designed structural height.

[0077] Pre-baking the coated glass in an oven removes most of the solvent from the photoresist, allowing it to form a solid film. This increases the adhesion of the photoresist layer to the glass surface, reducing the solvent content in the photoresist to 5-20% and decreasing its thickness by 10-20%.

[0078] (4) Expose the glass using a photomask exposure machine:

[0079] A raster vector graphic is used to create a photomask, which is then placed in a photomask exposure machine to expose the etched surface of the glass. To improve exposure efficiency, multiple patterns can be stitched together onto the same photomask to create a mosaic photomask for batch exposure of the glass.

[0080] (5) Immerse the glass in the developing solution for development:

[0081] The exposed glass is placed in a developing solution to dissolve the exposed portion, exposing the line spacing of the grating and leaving the photoresist of the grating line width.

[0082] (6) Place the glass in the oven for solidification:

[0083] The developed glass is baked to shrink and solidify its structure. High-temperature baking further removes the solvent from the photoresist, minimizing its solvent content and allowing it to solidify further, thus increasing the adhesion of the photoresist.

[0084] (7) Immerse the baked glass in the etching solution for etching:

[0085] The solidified glass is placed in an etching solution for etching. The etching solution is composed of hydrofluoric acid. The etching time needs to be adjusted according to the thickness of the photoresist. By using highly acid-resistant photoresist and low-concentration etching solution, the etching process is slow and uniform. The glass is etched through the line spacing of the grating, and the glass structure is laterally etched to form a 3D peak structure.

[0086] (8) Clean the etched glass to remove residual photoresist, etching solution and protective oil.

[0087] (9) Strengthening glass using a molten salt furnace:

[0088] The cleaned glass is placed in an oven for preheating, and then transferred to a molten salt furnace for strengthening. After strengthening, the glass is left to stand and drip salt, then allowed to cool naturally to room temperature. Finally, it is soaked in pure water and dried to complete the strengthening process.

[0089] Figure 9-11 Images are of glass products manufactured according to the above process in an embodiment of the present invention. (Compared to...) Figure 2-4 The texture patterns obtained by the embodiments of the present invention are more refined, the pattern complexity is higher, and the brightness and transparency are also significantly improved.

[0090] This invention provides a method for preparing 3D ultra-precision optical textures on glass surfaces. First, an appearance rendering is drawn, which is then converted into a pixel grayscale image. Next, a grating unit image is embedded into each pixel, and the grating unit image is rotated according to the grayscale value of that pixel. After all pixels are embedded in the grating unit image, a grating dot matrix vector image is formed. Then, a photomask made from the grating dot matrix vector image is placed in a photomask exposure machine to expose and develop the glass. Finally, an etching solution is used to etch the glass. Using this method, more precise appearance renderings can be designed. The grating units can provide uniform line width and spacing, facilitating precision control in subsequent etching stages and significantly improving the precision of the glass etching structure from hundreds of micrometers to 20 μm. The pattern reproduction is high, thus achieving the goal of preparing more precise optical texture patterns. Compared to laser direct-write lithography machines, photomask exposure machines do not require laser travel, thus avoiding numerous horizontal and vertical lines on the glass surface, resulting in a more aesthetically pleasing product. Furthermore, photomask exposure machines can perform batch exposure and one-time forming of glass, with higher exposure efficiency than laser direct-write lithography machines. The use of positive photoresist further improves the resolution of the pattern. By adjusting the photoresist, etchant concentration, and etching time, the etching process is slowed down, and lateral etching occurs simultaneously with downward etching. Due to the small linewidth, a 3D peak-shaped texture is formed, increasing the transparency and brightness of the texture effect, improving the consistency of the etched texture structure, and thus improving the overall product yield.

[0091] The above are merely specific embodiments of the present invention and should not be construed as limiting the scope of the present invention. Equivalent variations made by those skilled in the art based on this invention, as well as changes well-known to those skilled in the art, should still fall within the scope of the present invention.

Claims

1. A method for preparing 3D ultra-precision optical textures on a glass surface, characterized in that, The method includes the following steps: Step S1: Draw the appearance effect diagram of the 3D texture pattern; Step S2: Based on the preset period value of the grating unit and the product size, the resolution of the appearance rendering is set and pixel segmentation is performed to convert the appearance rendering into a pixel grayscale image. Step S3: Determine the line width and line spacing of the grating unit according to the preset period value of the grating unit, and draw the grating unit diagram in vector format. Step S4: For each pixel position in the pixel grayscale image, embed a raster unit image, and rotate the embedded raster unit image according to the grayscale value of the pixel. After embedding all pixel positions of the pixel grayscale image into the rotated raster unit image, a raster dot matrix image is obtained. The raster dot matrix image is then exported as a raster dot matrix vector image. Step S5: Place the photomask made of the grating dot vector image into the photomask exposure machine to expose and develop the glass; Step S6: Use an etching solution to etch the glass to form a textured pattern.

2. The method for preparing 3D ultra-precision optical textures on a glass surface according to claim 1, characterized in that, In step S2, resolution setting and pixel segmentation are performed according to the rule that each pixel corresponds to one grating unit.

3. The method for preparing 3D ultra-precision optical textures on a glass surface according to claim 1, characterized in that, Step S3 further includes determining the linewidth and line spacing of the grating by combining the desired visual effect and the acid resistance of the photoresist.

4. The method for preparing 3D ultra-precision optical textures on a glass surface according to claim 1, characterized in that, In step S4, rotating the embedded raster unit map according to the grayscale value of the pixel includes the following steps: The preset angle C is determined based on the visual effect of the 3D texture pattern; The preset angle C is divided into 256 equal parts, and the value of each part is taken as an angle component. The angle a of rotation of the raster unit map of each pixel is set to the gray value b of the current pixel multiplied by the angle component. The raster unit map of each pixel is rotated according to the set rotation angle.

5. The method for preparing 3D ultra-precision optical textures on a glass surface according to claim 4, characterized in that, The preset angle C is 90°.

6. The method for preparing 3D ultra-precision optical textures on a glass surface according to claim 4, characterized in that, The preset angle C is 180°.

7. The method for preparing 3D ultra-precision optical textures on a glass surface according to claim 1, characterized in that, In step S5, before exposing the glass, the process further includes: applying photoresist to the glass surface to be etched using a spraying machine, wherein the acid resistance of the photoresist is matched with the expected etching time, and the thickness of the photoresist layer is adjusted according to the designed texture structure height.

8. The method for preparing 3D ultra-precision optical textures on a glass surface according to claim 7, characterized in that, The photoresist is a positive photoresist.

9. The method for preparing 3D ultra-precision optical textures on a glass surface according to claim 7, characterized in that, In step S6, by adjusting the concentration and etching time of the etching solution, the etching solution can corrode the glass downwards while also corroding it to the left and right, forming a 3D peak-shaped texture.

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