Cover member for input device, and input device

JP2024050816A5Active Publication Date: 2025-09-29NIPPON ELECTRIC GLASS CO LTD
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Patent Information

Application Number
JP2024016376
Authority / Receiving Office
JP · JP
Patent Type
Applications
Current Assignee / Owner
Filing Date
2024-02-06
Publication Date
2025-09-29
Estimated Expiration
2039-11-07

AI Technical Summary

Technical Problem

Existing pen input devices with smooth glass substrates experience tip slippage and discomfort due to excessive friction, making writing with input pens uncomfortable.

Method used

A cover member for input devices with controlled surface unevenness, characterized by specific cutoff values of high-pass and low-pass filters, reduces contact area and friction, enhancing writing quality while maintaining transparency and visibility.

Benefits of technology

The solution improves writing comfort and quality by preventing excessive slip and friction, ensuring smooth operation with input pens and fingers, while maintaining display visibility and resistance to scratches.

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Abstract

To provide a cover member for an input device, etc., capable of improving the writing feeling of input means such as an input pen to an input device.SOLUTION: A cover member for an input device arranged at a front side of a display device 30 in an input device 10 has irregularity on at least one principal surface 20a. In the principal surface 20a having the irregularity, when the size of interval width of the irregularity is regarded as A and the diameter of a tip part of an input medium is regarded as B when a cut-off value of a high-pass filter λc is regarded as a value of 1.6 times the interval width of the irregularity of a measurement cross-sectional curve and a cut-off value of a low-pass filter λs is regarded as 25 μm, the relation between them satisfies 0.02<[A / B]<1.SELECTED DRAWING: Figure 2
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Description

[Technical field]

[0001] The present invention relates to a cover member for an input device and an input device including the same. [Background technology]

[0002] 2. Description of the Related Art Pen input devices capable of inputting characters, figures, and the like using an input pen or the like have been known. In such a pen input device, a transparent cover member made of a glass substrate or the like is disposed on the front side of a display device such as a liquid crystal display, and various input operations can be performed by touching and moving an input pen against this cover member. When a glass substrate is used as the cover member of a pen input device, the surface of the glass substrate is generally formed smoothly with little unevenness, so that when an input pen is touched and moved against the surface of the glass substrate, the pen tip slips, resulting in a poor writing experience.

[0003] For example, Patent Document 1 discloses that in order to improve the writing feel of an input pen in a pen input device, the surface of the cover glass of the input device is made uneven to improve friction. The maximum valley depth of the unevenness is 10 to 400 nm, and the average interval is 500 to 2000 nm. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2018-20942 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, when an input pen is brought into contact with the surface of the cover glass and moved, the uneven layer formed on the surface of the cover glass member causes the tip of the pen to catch too much and to slide, making it difficult to obtain a good writing feel like that of paper and a ballpoint pen.

[0006] Therefore, the present invention has been made in consideration of such current problems, and provides a cover member for an input device that provides an improved writing feel when using an input medium such as an input pen, and an input device equipped with the same. [Means for solving the problem]

[0007] The problem to be solved by the present invention has been described above, and the means for solving this problem will now be described.

[0008] The cover member for an input device that solves the above-mentioned problems and the input device including the same have the following features. That is, the cover member for an input device according to the present invention is a cover member for an input device arranged on the front side of a display device in an input device, and has unevenness on at least one of its main surfaces, and is characterized in that, on the main surface having unevenness, the cutoff value of the high-pass filter λc is set to a value 1.6 times the spacing width of the unevenness of the measured cross-sectional curve, and the cutoff value of the low-pass filter λs is set to 25 μm, and when the size of the spacing width of the unevenness is A and the diameter of the tip of the input medium is B, the relationship between the two satisfies 0.02<[A / B]<1. With this configuration, the contact area between the tip of the input medium and the cover member can be reduced, and an excessive increase in friction can be reduced, resulting in an excellent writing experience with an input medium such as an input pen.

[0009] Furthermore, the cover member for an input device according to the present invention is characterized in that, on the main surface having the irregularities, when the cutoff value of the high-pass filter λc is set to 1.6 times the interval width of the irregularities on the measured cross-sectional curve and the cutoff value of the low-pass filter λs is set to 25 μm, the maximum height width of the irregularities is 3 to 1000 nm and the interval width A of the irregularities is 50 to 1000 μm. With this configuration, it is possible to prevent the input means from being too slippery when operated with an input medium such as an input pen on the input device, and it is possible to provide an excellent writing feel when using the input means with an input medium such as an input pen.

[0010] In addition, in the cover member for an input device according to the present invention, on the main surface having the irregularities, when the cutoff value of the high-pass filter λc is 25 μm, the surface roughness (three-dimensional) arithmetic mean height Sa of the irregularities is 1 to 50 nm and the spacing width of the irregularities is 0.01 to 10 μm. By adopting such a configuration having two types of unevenness, it is possible to make the operation of the input means with an input medium such as an input pen on the input device neither too slippery nor too easy, thereby providing an excellent writing feel when using the input means with an input medium such as an input pen.

[0011] In the cover member for an input device according to the present invention, the input medium has a tip end with a diameter of 0.5 mm to 10 mm.

[0012] Moreover, the cover member for an input device according to the present invention has a haze of less than 10% in the wavelength range of visible light. This makes it possible to maintain the transparency of the cover member for the input device, and therefore the visibility of the display device can be maintained.

[0013] An input device according to the present invention includes the cover member for an input device according to any one of claims 1 to 4, a display device, and a detection circuit for detecting an input. This makes it possible to provide an excellent writing feel when using an input medium such as an input pen for inputting to the input device.

[0014] The input device according to the present invention further comprises an input pen that makes an input to the input device by moving while in contact with the main surface of the input device cover member. With this configuration, it is possible to provide an excellent writing experience with an input medium such as an input pen on the input device. Effect of the Invention

[0015] According to the present invention, it is possible to provide an excellent writing feel when using an input medium such as an input pen for inputting to an input device. [Brief description of the drawings]

[0016] [Figure 1] 1 is a schematic side cross-sectional view showing an input device. [Diagram 2] 1 is a diagram showing the relationship between A, which is the size of the gap width between the projections and recesses of the measured cross-sectional curve of the main surface, and B, which is the diameter of the tip of an input medium such as an input pen. [Diagram 3] 1A and 1B are diagrams showing a measured cross-sectional curve of a main surface, irregularities with large gap widths, and irregularities with small gap widths. [Figure 4] FIG. 13 is a diagram showing the cutoff values ​​of a high-pass filter λc and a low-pass filter λs. [Diagram 5] 1 is a diagram showing a state in which a pen tip comes into contact with a main surface of a glass substrate on which two types of unevenness, large and small, with different spacing between the unevenness, are formed. [Figure 6] 13 is a diagram showing the state in which the tip of a pen comes into contact with the main surface of a glass substrate that does not have the small projections and recesses out of two types of projections and recesses with different spacing widths. FIG. [Figure 7] This figure shows how the pen tip comes into contact with the main surface of a glass substrate that has two types of unevenness, large and small, with different spacing between the unevennesses, and where the spacing between the larger unevennesses is greater than the diameter of the pen tip. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Next, an embodiment for carrying out an input device cover member according to the present invention and an input device including the same will be described with reference to the accompanying drawings.

[0018] An input device 10 shown in FIG. 1 is one embodiment of an input device equipped with a cover member for an input device according to the present invention. The input device 10 comprises a display element 30 for displaying images, a glass substrate 20 as a cover member arranged on the front side of the display element 30, a digitizer circuit 40 arranged on the rear side of the display element 30, and an input pen 50. The glass substrate 20 is an example of a cover member for an input device according to the present invention, and the digitizer circuit 40 is an example of a detection circuit for detecting an input according to the present invention. The "front side" of the display element 30 refers to the side on which an image is displayed, and the "rear side" of the display element 30 refers to the side opposite to the side on which an image is displayed. In Fig. 1, the "front side" of the display element 30 is the upper side of the page, and the "rear side" is the lower side of the page.

[0019] The input device 10 is capable of inputting characters, figures, and the like by moving an input pen 50 in contact with the glass substrate 20. Input to the input device 10 can also be performed by input means other than the input pen 50. For example, characters, figures, and the like can be input by moving a user's finger in contact with the glass substrate 20. The input device 10 is, for example, a tablet terminal. The tablet terminal broadly refers to an input display device having a display function and an input function. Tablet terminals include devices such as tablet PCs, mobile PCs, smartphones, and game consoles.

[0020] The glass substrate 20 is formed of a transparent glass plate having irregularities formed on at least one of the main surfaces 20a. For example, a glass plate made of aluminosilicate glass or borosilicate glass can be used as the glass substrate 20. When the glass substrate 20 is a glass plate made of alkali-containing aluminosilicate glass, the glass substrate 20 may have a chemically strengthened layer on the surface. Details of the glass substrate 20 will be described later.

[0021] The glass substrate 20 is disposed so that the principal surface 20a on which the irregularities are formed is the surface that comes into contact with the input pen 50.

[0022] The digitizer circuit 40 includes a detection sensor for detecting input from an input means such as an input pen 50. The input pen 50 is an input tool shaped like a writing implement such as a pencil or a ballpoint pen, and the pen tip 51 that contacts the glass substrate 20 is made of synthetic resin materials such as elastomer and polyacetal resin, or fibers. The diameter of the pen tip 51 made of these materials is easily affected by the width of the unevenness. Therefore, the writing feel is particularly excellent when the pen tip 51 of the input pen 50 is moved in contact with the main surface 20a of the glass substrate 20 on which unevenness is formed, the ratio of the diameter of the pen tip 51 to the interval width of the unevenness being specified.

[0023] In this embodiment, the glass substrate 20 is used as the cover member for the input device, but the present invention is not limited thereto, and a resin substrate made of synthetic resin and having irregularities formed on at least one of its main surfaces can also be used as the cover member. In this case, the irregularities on the resin substrate can be formed, for example, by subjecting the main surface of the resin substrate to a blasting process such as wet blasting, or by subjecting the main surface of the resin substrate to an embossing process.

[0024] It is also possible to use a resin layer having an uneven surface formed on at least one of the main surfaces of a glass substrate as a cover member. In this case, the cover member can be constructed by attaching a resin sheet having an uneven surface formed on the main surface of the glass substrate. The unevenness of the resin sheet can be formed, for example, by embossing the surface of the resin sheet or by forming a synthetic resin having powder particles mixed therein into a sheet shape. Furthermore, the resin layer can also be formed by a spray method in which a synthetic resin is sprayed onto the main surface of the glass substrate.

[0025] However, when a glass substrate 20 is used as a cover member, the surface has a higher hardness than when a resin substrate or a glass substrate having a resin layer formed on the main surface thereof is used, and therefore has the advantage that the surface is less likely to be scratched.

[0026] Next, the glass substrate 20 will be described. The glass substrate 20 is one embodiment of a cover member for an input device according to the present invention. A main surface 20a of the glass substrate 20 has projections and recesses formed thereon.

[0027] 2, the glass substrate 20 has a main surface 20a having irregularities, and the cutoff value of the high-pass filter λc is set to a value 1.6 times the interval width of the irregularities of the measured cross-sectional curve, and the cutoff value of the low-pass filter λs is set to 25 μm. When the size of the interval width of the irregularities is A and the diameter of the tip of an input medium such as an input pen is B, [A / B] is in the range of 0.02 to 1 (but does not include 1). 0.03 to 0.99 is preferable, 0.05 to 0.95 is more preferable, and 0.07 to 0.90 is particularly preferable. If the value of [A / B] is too small or too large, appropriate frictional force cannot be obtained, and a good writing feel cannot be obtained.

[0028] As shown in Fig. 3, the unevenness is composed of two different types of unevenness, large and small. The unevenness with a large gap width has a maximum height width Rz of 3 nm to 1000 nm, and an unevenness gap width RSm of 50 µm to 10000 µm. The unevenness with a small gap width has a three-dimensional arithmetic mean height Sa of 1 nm to 50 nm, and an unevenness gap width RSm of 0.01 µm to 10 µm. The maximum height width Rz is preferably larger than the three-dimensional arithmetic mean height Sa. Furthermore, the maximum height width Rz is more preferably 1.1 to 500 times the three-dimensional arithmetic mean height Sa.

[0029] Here, in the case of unevenness with a large gap width, the maximum height width Rz is the sum of the highest peak height and the deepest valley depth in the unevenness, and the gap width RSm of the unevenness is the average of each periodic length Xs of the unevenness in a predetermined reference length. Also, in the case of unevenness with a small gap width, the three-dimensional arithmetic mean height Sa is the average of the absolute values ​​of the peak height Z1 and valley depth Z2 of the unevenness in a predetermined three-dimensional area, and the gap width RSm of the unevenness is the average of each periodic length Xs of the unevenness in a predetermined reference length.

[0030] As shown in Figures 3 and 4, the values ​​of the maximum height width Rz and the spacing width RSm of the asperities with the above-mentioned large spacing width are values ​​obtained when the cutoff value λc1 of the high-pass filter λc for cutting off long wavelength components from the measured cross-sectional curve of main surface 20a is set to a value 1.6 times the spacing width of the asperities of the measured cross-sectional curve, and the cutoff value λs1 of the low-pass filter λs for cutting off short wavelength components from the measured cross-sectional curve of main surface 20a is set to 25 μm.

[0031] The three-dimensional arithmetic mean height Sa and the unevenness interval RSm in the small-interval unevenness described above are values ​​obtained when the cutoff value λc2 of the high-pass filter λc for cutting off long-wavelength components from the measured cross-sectional curve of the main surface 20a is set to 25 μm. By applying the high-pass filter λc having the cutoff value λc2 to the measured cross-sectional curve of the main surface 20a, the waviness components and the large-interval unevenness components of the main surface 20a are removed, and a curve of small-interval unevenness is obtained.

[0032] By setting the shape of the large gap width unevenness and the shape of the small gap width unevenness on the main surface 20a of the glass substrate 20 within such ranges, the visibility of the display element 30 can be maintained in the input device 10, and the writing feel of the input means such as the input pen 50 can be improved. In addition, the occurrence of glare called sparkling due to the interference of scattered light caused by the formed unevenness can be suppressed. Furthermore, since no resin layer is formed on the main surface 20a of the glass substrate 20 and the unevenness is directly formed, the surface has high scratch resistance and is not easily scratched, so the visibility of the display element 30 is not reduced.

[0033] The large gap unevenness affects the contact between the main surface 20a and the pen tip 51 of the input pen 50. The pen tip 51 contacts the main surface 20a of the glass substrate 20 at the convex portion of the large gap unevenness, but does not contact at the concave portion of the large gap unevenness. This allows a combination of moderate increases and decreases in the frictional force between the pen tip 51 and the main surface 20a to prevent an excessive increase or decrease in the frictional force between the pen tip 51 and the main surface 20a, and the writing feel of the input pen 50 can be improved. Even when the user's finger is moved while in contact with the glass substrate 20, the finger can be moved moderately smoothly, and the writing feel when inputting with the finger can be improved. In this way, it is possible to improve the writing feel of the input means such as the input pen 50 and the finger.

[0034] The upper limit of the maximum height width Rz of the large gap width unevenness is set to 1000 nm, but is preferably set to 500 nm, and more preferably set to 200 nm. The lower limit of the maximum height width Rz of the large gap width unevenness is set to 3 nm, but is preferably set to 4 nm, and more preferably set to 5 nm. The upper limit of the interval width RSm of the large gap width unevenness is set to 10000 μm, but is preferably set to 9500 μm, and more preferably set to 9000 μm. The lower limit of the interval width RSm of the large gap width unevenness is set to 50 μm, but is preferably set to 100 μm, more preferably set to 500 μm, and more preferably set to 1500 μm.

[0035] The small gap width unevenness contributes to an increase in friction between the main surface 20a of the glass substrate 20 and the pen tip 51. This makes it possible to prevent the pen tip 51 from slipping on the main surface 20a of the glass substrate 20, and to improve the writing feel of the input pen 50. Even when the user's finger is moved while in contact with the glass substrate 20, the finger can be moved moderately smoothly, and the writing feel when inputting with the finger can be improved. In this way, it is possible to improve the writing feel of the input means such as the input pen 50 or a finger. The upper limit value of the three-dimensional arithmetic mean height Sa of the small gap width unevenness is set to 50 nm, but it is preferably set to 40 nm, and more preferably set to 30 nm. The upper limit value of the interval width RSm of the small gap width unevenness is set to 10 μm, but it is preferably set to 7 μm, and more preferably set to 5 μm. The lower limit of the gap width RSm of the small gap width irregularities is set to 0.01 μm, preferably 0.1 μm, and more preferably 0.5 μm.

[0036] Furthermore, the main surface 20a of the glass substrate 20 provides an excellent writing feel for the pen tip 51 made of materials that are prone to catching on uneven surfaces, such as the above-mentioned elastomers such as silicone rubber, resin materials such as polyacetal resin, metals, and fibers. The diameter of the tip of the pen tip is 0.5 mm to 10 mm. The smaller the diameter of the tip, the finer the input can be with thinner lines, but if it is too small, the digitizer circuit 40 cannot recognize it. Therefore, the range of 1 mm to 9.5 mm is preferable, and the range of 1.2 mm to 9 mm is more preferable.

[0037] The glass substrate 20 is formed so that the haze, which is an index of transparency and indicates cloudiness, is less than 10% in the wavelength range of visible light (380 nm to 780 nm) from the viewpoint of visibility of an image on the display element 30 when the image is viewed through the glass substrate 20. By making the haze of the glass substrate 20 less than 10%, the transparency of the glass substrate 20 can be maintained, and the visibility of the display element 30 can be maintained.

[0038] In this embodiment, the haze of the glass substrate 20 is set to less than 10%, preferably less than 7%, more preferably less than 5%, and even more preferably less than 4%.

[0039] In addition, an anti-reflection film for reducing the reflectance of the side that comes into contact with the input pen, or an anti-fouling film for preventing fingerprints from adhering and for imparting water- and oil-repellency can be formed on the main surface 20a of the glass substrate 20.

[0040] When the glass substrate 20 is used as a cover member for the input device 10, the anti-reflection film is provided at least on the main surface 20a on the front side of the glass substrate 20 (the side that comes into contact with the input pen 50). Furthermore, when there is a gap between the glass substrate 20 and the display element 30, it is preferable that the main surface 20a on the rear side (the display element 30 side) of the glass substrate 20 also has an anti-reflection film. As the anti-reflection film, for example, a low refractive index film having a lower refractive index than the glass substrate 20, or a dielectric multilayer film in which a low refractive index film having a relatively low refractive index and a high refractive index film having a relatively high refractive index are alternately laminated is used. The anti-reflection film can be formed by a sputtering method, a CVD method, or the like.

[0041] When the main surface 20a of the glass substrate 20 has an anti-reflection coating, the irregularities on the main surface 20a of the glass substrate 20 are formed so that the irregularities on the surface of the anti-reflection coating fall within the above-mentioned surface roughness ranges (the maximum height width Rz of the irregularities with a large interval width and the interval width RSm of the irregularities, and the three-dimensional arithmetic surface height Sa of the irregularities with a small interval width and the interval width RSm of the irregularities). When the main surface 20a of the glass substrate 20 has an anti-reflection coating, the irregularities on the main surface 20a of the glass substrate 20 are formed so that the haze of the glass substrate 20 having the anti-reflection coating falls within the above-mentioned range. Note that, when the interval width RSm of the irregularities and the three-dimensional arithmetic mean height Sa of the irregularities are measured after the anti-reflection coating is formed, a 10 nm Au film is formed and then these values ​​are measured.

[0042] When the glass substrate 20 is used as a cover member of the input device 10, the anti-soiling film is provided on the main surface 20a of the front side (the side that comes into contact with the input pen 50) of the glass substrate 20. The anti-soiling film preferably contains a fluorine-containing polymer containing silicon in the main chain. As the fluorine-containing polymer, for example, a polymer having a -Si-O-Si- unit in the main chain and a water-repellent functional group containing fluorine in the side chain can be used. The fluorine-containing polymer can be synthesized, for example, by dehydration condensation of silanol. When the front main surface 20a of the glass substrate 20 has an anti-reflection film and an anti-soiling film, the anti-reflection film is formed on the main surface 20a of the glass substrate 20, and the anti-soiling film is formed on the anti-reflection film.

[0043] When the main surface 20a of the glass substrate 20 has an antifouling film, or when the main surface 20a of the glass substrate 20 has an antireflection film and an antifouling film, the unevenness of the main surface 20a of the glass substrate 20 is formed so that the unevenness of the surface of the antifouling film falls within the above-mentioned surface roughness range (the maximum height width Rz of the unevenness with a large interval width and the interval width RSm of the unevenness, and the three-dimensional arithmetic surface height Sa of the unevenness with a small interval width and the interval width RSm of the unevenness). In addition, when the main surface 20a of the glass substrate 20 has an antifouling film, or when the main surface 20a of the glass substrate 20 has an antireflection film and an antifouling film, the unevenness of the main surface 20a of the glass substrate 20 is formed so that the haze of the glass substrate 20 after the antifouling film is formed, or the haze of the glass substrate 20 after the antireflection film and the antifouling film are formed, falls within the above-mentioned range.

[0044] Next, a method for manufacturing the glass substrate 20 will be described. The unevenness formed on at least one of the main surfaces 20a of the glass substrate 20 is formed by combining at least one of the treatment methods such as wet blasting, chemical etching, and silica coating on the main surface 20a. The wet blasting is a process in which abrasive grains composed of solid particles such as alumina and liquid such as water are uniformly stirred to form a slurry, which is then sprayed at high speed from a spray nozzle against a workpiece made of glass using compressed air, thereby forming fine unevenness on the workpiece. Furthermore, a round nozzle with an area of ​​the slurry spray outlet narrowed down to a small area compared to the area of ​​the workpiece is used as the nozzle for spraying the slurry, and various surface shapes can be formed by moving this round nozzle relative to the workpiece.

[0045] In the wet blasting process, when the slurry is sprayed at high speed and collides with the workpiece, the abrasive grains in the slurry scrape, hit, and rub the surface of the workpiece, forming fine irregularities on the surface of the workpiece. In this case, the abrasive grains sprayed on the workpiece and the fragments of the workpiece scraped by the abrasive grains are washed away by the liquid sprayed on the workpiece, so that the number of particles remaining on the workpiece is reduced. In addition to the irregularities with small intervals, the irregularities with large intervals can be created by partially spraying the slurry on the surface of the workpiece by scanning the nozzle arbitrarily over the workpiece. The glass substrate 20 is obtained by preparing the workpiece having two types of irregularities, large and small, with different intervals between the irregularities on the surface, into the desired size and shape by cutting or the like.

[0046] The surface roughness of the small gap width unevenness formed on the main surface of the workpiece by wet blasting can be adjusted mainly by the particle size distribution of the abrasive grains contained in the slurry and the injection pressure when the slurry is injected onto the workpiece. The maximum height width Rz of the large gap width unevenness and the gap width RSm of the unevenness can be adjusted by the size of the nozzle that injects the slurry, the feed pitch width, and the injection pressure.

[0047] In wet blasting, when the slurry is sprayed onto the workpiece, the liquid carries the abrasive grains to the workpiece, so that finer abrasive grains can be used than in dry blasting, and the impact when the abrasive grains collide with the workpiece is reduced, making it possible to perform precise processing. In this way, by subjecting the workpiece to wet blasting, it is easy to form two types of large and small irregularities with different spacing widths between the irregularities of appropriate size on the main surface 20a of the glass substrate 20, and it is possible to provide an excellent writing experience with input means such as the input pen 50 without impairing the transparency of the glass substrate 20.

[0048] In dry blasting, friction occurs when the sprayed abrasive grains collide with the workpiece, generating processing heat in the workpiece. However, in wet blasting, the liquid constantly cools the surface of the workpiece during processing, so the workpiece is not heated by the blasting process. It is also possible to form irregularities on the main surface 20a of the glass substrate 20 by performing a dry blasting process. However, in the dry blasting process, the impact when the abrasive grains collide with the main surface 20a of the glass substrate 20 is too large, so that the surface roughness of the main surface 20a on which the irregularities are formed tends to increase, and the transparency of the glass substrate 20 tends to be impaired.

[0049] The chemical etching process is a process in which the main surface 20a of the glass substrate 20 is chemically etched with hydrogen fluoride (HF) gas or hydrofluoric acid.

[0050] The silica coating process is a process in which a coating agent containing a matrix precursor such as a silica precursor and a liquid medium that dissolves the matrix precursor is applied to the main surface 20a of the glass substrate 20, and then heated. EXAMPLES

[0051] Next, an embodiment of the glass substrate 20 having two types of unevenness, large and small, with different intervals between the unevennesses formed on the main surface 20a will be described, although the glass substrate 20 is not limited to this.

[0052] [Sample preparation] In this example, Samples 1 to 9 were prepared as examples of the glass substrate 20, and Samples 10 to 12 were prepared as comparative examples. The glass substrate 20 used in Samples 1 to 12 was made of alkali-containing aluminosilicate glass having a thickness of 1.1 mm.

[0053] For the glass substrates 20 of Samples 1 to 9 as examples and Sample 12 as a comparative example, two types of unevenness, large and small, with different unevenness intervals, were formed on one of the main surfaces 20a by performing wet blasting. Specifically, for the glass substrates 20 of Samples 1 to 9 and Sample 12, a slurry was prepared by uniformly mixing abrasive grains made of alumina with a grain size of #4000, #6000, or #8000 and water, and the glass substrates 20 were placed on a processing stage, and wet blasting was performed by spraying air with a processing pressure of 0.1 to 0.3 MPa over the entire one of the main surfaces 20a of the glass substrate 20 while scanning the nozzle at a speed of 0.5 mm / s. The round nozzle used for wet blasting is a nozzle that narrows the cross-sectional area of ​​the slurry injection port relative to the area of ​​the main surface 20a, and partially injects the slurry onto the main surface 20a. The interval width of the large-interval unevenness was varied by changing the scanning distance of the round nozzle. The maximum height width Rz of the large-interval unevenness was varied by increasing the number of scans. The three-dimensional arithmetic mean height Sa of the small-interval unevenness was varied by changing the particle size of the alumina or by changing the processing pressure. The abrasive grains used were polygonal.

[0054] For samples 1 to 9 and 12, the interval width of the large-interval unevenness was created by varying the scanning distance of the round nozzle from 500 to 3000 μm. The maximum height width Rz of the large-interval unevenness was created by varying the number of round nozzle scans from 2 to 5 times that of sample 1. The three-dimensional arithmetic mean height Sa of the small-interval unevenness was created by changing the alumina particle size from #4000 to 8000 and increasing the processing pressure in the range of 0.1 to 0.2 MPa.

[0055] The main surface 20a of the glass substrate 20 of the sample 10, which is a comparative example, is not treated. In other words, the glass substrate 20 of the sample 10 is untreated. For the glass substrate 20 of the sample 11, which is a comparative example, a SiO2 coating film is formed on one of the main surfaces 20a by drying a liquid containing a SiO2 component.

[0056] [Surface roughness measurement] The surface roughness of the main surface 20a of the glass substrate 20 was measured for Samples 1 to 12. For Samples 1 to 10 and 12, the surface roughness was measured on the main surface 20a that had been subjected to a wet blasting treatment, and for Sample 11, the surface roughness was measured on one of the main surfaces 20a.

[0057] The measured surface roughness parameters were the maximum height Rz and the spacing RSm between the projections and recesses for irregularities with large spacing widths, and the three-dimensional arithmetic surface height Sa and the spacing RSm between the projections and recesses for irregularities with small spacing widths. The surface roughness measurements were performed using a white light interference microscope.

[0058] The white light interference microscope used was a white light interference microscope (New View 7300) manufactured by Zygo, and measurements were performed based on JIS B0601-2013. For samples 1 to 10 and 12, the measurement conditions for the large gap width unevenness were a 2.5x objective lens and a 1x zoom lens, the camera pixel count was 640x480, and the number of integrations was 1 for a measurement area of ​​2827x2120μm. When measuring the maximum height width Rz of the large gap width unevenness and the gap width RSm of the unevenness, the cutoff value λc1 of the high-pass filter λc was set to about 1.6 times the gap width RSm of the unevenness, and the cutoff value λs1 of the low-pass filter λs was set to 25μm. The measurement conditions for the small gap width unevenness were a 50x objective lens and a 2x zoom lens, the camera pixel count was 640x480, and the number of integrations was 8 for a measurement area of ​​74x55μm. The cutoff value λc2 of the high-pass filter λc when measuring the three-dimensional arithmetic mean height Sa of the small gap irregularities and the gap width RSm of the irregularities was set to 25 μm. For sample 11, the measurement conditions for the large gap irregularities were a 50x objective lens, a 0.5x zoom lens, a 282×210 μm measurement area, a camera pixel count of 640×480, and 8 integrations. The cutoff value λc1 of the high-pass filter λc when measuring the maximum height Rz of the large gap irregularities and the gap width RSm of the irregularities was set to 52.9 μm, and the cutoff value λs1 of the low-pass filter λs was set to 1.3 μm.

[0059] [Surface roughness measurement results] The following describes the results of measuring the surface roughness of samples 1 to 12. Table 1 shows the results.

[0060] [Table 1]

[0061] As shown in Table 1, the maximum height width Rz of the unevenness with large intervals is in the range of 25 nm to 125 nm for Samples 1 to 9 of the embodiment and Sample 12 of the comparative example, and the maximum height width Rz tends to increase as the number of scans of the wet blasting treatment increases. No unevenness with large intervals was observed for Sample 10, which is an untreated comparative example. The maximum height width Rz of Sample 11, which is a comparative example with a SiO2 coating film, was 1225 nm.

[0062] The spacing width RSm of the unevenness with large spacing is in the range of 500 μm to 3000 μm for Samples 1 to 9 of the embodiment and Sample 12 of the comparative example. No unevenness with large spacing was observed for Sample 10, which is an untreated comparative example. The spacing width RSm of the unevenness for Sample 11, which is a comparative example and has a SiO2 coating film, is 30 μm.

[0063] The three-dimensional arithmetic surface height Sa of small-gap irregularities is in the range of 4.5 nm to 5.3 nm for Samples 1 to 9 of the embodiments and Comparative Example 12. The three-dimensional arithmetic surface height Sa of Sample 10, an untreated Comparative Example, is 0.2 nm, which is smaller than Samples 1 to 9 and 12, and small irregularities were not observed for Sample 11, a Comparative Example that is subjected to a SiO2 coating film.

[0064] [Haze measurement] The haze was measured for Samples 1 to 12. The haze was measured using an ultraviolet, visible, near-infrared analytical photometer (UV-3100PC) manufactured by Shimadzu Corporation, based on JIS K7361-1-1997.

[0065] [Haze measurement results] As shown in Table 1, the haze of Samples 1 to 9, which are examples, was in the range of 1.0% to 1.8%, and was not significantly different from that of untreated Samples 10 and 12. On the other hand, Sample 11, which is a comparative example that was provided with a SiO2 coating film, had a high haze of 34%.

[0066] [Visibility rating] When the glass substrate 20 of Samples 1 to 12 was placed on the front side of the display element 30 of the input device 10, the visibility of the image displayed on the display element 30 was evaluated. The evaluation method was to evaluate whether or not the image displayed on the display element 30 had any blurring, using the following three-level scale: ◎: The image was clear and no blurring was observed in the image, ○: The image was fully visible, but slight image blurring was observed, ×: The image was unclear and image blurring was noticeable.

[0067] [Visibility evaluation results] As shown in Table 1, the image visibility was rated as ⊚ for Samples 1 to 9, which are examples. The untreated comparative sample 10 was marked with an ⊚ rating, the comparative sample 11 with a SiO2 coating film was marked with an x ​​rating, and the comparative sample 12 was marked with an ⊚ rating.

[0068] [Input medium] The following input pens were used as input media. For samples 1 to 3 and 10 to 12, a BambooTip manufactured by Wacom was used. The pen tip was made of resin and had a diameter of 1.9 mm. For samples 4 to 5, an Apple Pencil manufactured by Apple was used. The pen tip was made of resin and had a diameter of 8.9 mm. For samples 6 to 7, a KP-503E manufactured by Wacom was used. The pen tip was made of rubber and had a diameter of 1.7 mm. For samples 8 to 9, a TB-TPG03BK manufactured by ELECOM was used. The pen tip was made of conductive fiber and had a diameter of 8 mm.

[0069] [Gap width of large gap unevenness A / diameter of tip of input medium B] When the spacing width RSm of the unevenness in the large spacing unevenness is A and the diameter of the tip of the input medium is B, the ratio of A to B is expressed as [A / B], and the ratio was in the range of 0.11 to 0.79 for Samples 1 to 9, which are examples. On the other hand, the calculation was impossible for Sample 10, which is an untreated comparative example, the ratio was 0.01 for Sample 11, which is a comparative example with a SiO2 coating film, and 1.58 for Sample 12, which is a comparative example.

[0070] [Evaluation of writing feel] A sensory test was conducted to evaluate the writing feel when characters, figures, etc. were inputted to the glass substrate 20 using the input pen 50. The evaluation method used the above-mentioned input pen as the input pen 50, and had a total of 20 people, both male and female, in their 20s to 50s, rate the writing feel on the glass substrate 20 on a 7-point scale from "very comfortable to write with" to "very uncomfortable to write with," and the average score was used for evaluation.

[0071] [Writing feel evaluation results] As shown in Table 1, the writing feel was 3.9 or more for Samples 1 to 9, which are examples, and 3.7 or less for Sample 10, which is an untreated comparative example, Sample 11, which is a comparative example with a SiO2 coating film, and Sample 12, which is a comparative example.

[0072] [Overall evaluation of each sample] 5, for Samples 1 to 9 as examples, two types of unevenness, large and small, with different spacing between the appropriate unevenness formed on the main surface 20a with which the pen tip 51 of the input pen 50 comes into contact, prevent the pen tip 51 from slipping on the main surface 20a of the glass substrate 20, and a combination of appropriate increases and decreases in the frictional force between the pen tip 51 and the main surface 20a results in a good writing feel and a good evaluation result of visibility of ⊚. On the other hand, for Sample 10, which is an untreated comparative example, the unevenness of the main surface 20a with which the input pen 50 comes into contact is small, making it easy to slip, resulting in a poor writing feel.

[0073] As shown in Fig. 6, sample 11, a comparative example with a SiO2 coating film, does not have two types of unevenness, large and small, with different spacing between the unevenness, so the pen tip 51 does not slide smoothly, causing snagging and resulting in a poor writing feel. On the other hand, as shown in Fig. 7, sample 12, a comparative example with an [A / B] value that is too large, could not prevent snagging, making it difficult to slide and resulting in a poor writing feel. [Industrial Applicability]

[0074] The present invention is applicable to an input device that can input characters, figures, etc. using an input means such as an input pen, and to a cover member for an input device that is provided with the input device, and in particular to a cover member for an input device that is arranged on the front side of a display device in the input device and has irregularities on at least one of its main surfaces, and to an input device that is provided with the cover member for an input device. [Explanation of symbols]

[0075] 10 Input Devices 20 Glass substrate (cover component for input device) 20a Main surface 30 Display elements 40 Digitizer Circuit 50 Input Pen

Claims

1. The input device is disposed on the front side of the display device, A cover member for an input device, the cover member being configured such that a tip end of an input medium having an outwardly convex spherical shape is moved while contacting a main surface on the side opposite to the display device side, the tip of the input medium has a diameter of 1.7 to 8 mm; the input device cover member has two different types of unevenness, large and small, on at least one main surface; In the main surface having the irregularities, When the cutoff value of the high-pass filter λc is set to 1.6 times the interval width of the large concave-convex portions of the measured profile curve and the cutoff value of the low-pass filter λs is set to 25 μm, the interval width of the large concave-convex portions is 500 to 3000 μm, and When the size of the gap width between the large projections and recesses is A and the diameter of the tip of the input medium is B, the relationship between the two satisfies 0.13≦[A / B]≦0.79, In the main surface having the irregularities, When the cutoff value of the high-pass filter λc is 25 μm, the spacing between the small irregularities is 2.4 to 2.9 μm. A cover member for an input device, characterized in that:

2. In the main surface having the irregularities, When the cutoff value of the high-pass filter λc is set to a value 1.6 times the interval width of the large concave-convex portions of the measured profile curve and the cutoff value of the low-pass filter λs is set to 25 μm, the maximum height width of the large concave-convex portions is 25 to 125 nm.

2. The cover member for an input device according to claim 1, wherein the cover member is a cover member for an input device.

3. The haze is less than 10% in the wavelength range of visible light.

3. The cover member for an input device according to claim 1 or 2, wherein the cover member is a cover member for an input device.

4. A cover member for an input device according to any one of claims 1 to 3, a display device, and a detection circuit for detecting an input.

1. An input device comprising:

5. an input medium that moves while in contact with a main surface of the input device cover member to input to the input device; The input medium is An input pen having a tip portion with an outwardly convex spherical shape, 5. The input device according to claim 4, wherein: