Cover member for input device and input device

Abstract

The present invention provides a cover member for an input device and an input device. The cover member for an input device is arranged on the front side of a display device in the input device, wherein the cover member for the input device has concavities and convexities on at least one main surface, and in the main surface having the concavities and convexities, when the cutoff value of the high-frequency filter λc is set to a value 1.6 times the interval width of the concavities and convexities of the measured cross-sectional curve and the cutoff value of the low-frequency filter λs is set to 25 μm, the maximum height width of the concavities and convexities is 3 to 1000 nm, and when the cutoff value of the high-frequency filter λc is set to 25 μm, the three-dimensional arithmetic mean roughness Sa of the concavities and convexities is 1 to 50 nm.

Description

[0001] This invention application is a divisional application of the invention application with application number 201880059929.8 and invention name “Cover member for input device and input device” filed by the applicant Nippon Electric Glass Co., Ltd. on August 28, 2018. Technical Field

[0002] The present invention relates to a cover member for an input device and an input device. Background Art

[0003] Conventionally, there is known a pen input device that can input characters, graphics, and the like using an input pen.

[0004] In such a pen input device, a transparent cover member made of a glass substrate or the like is arranged on the front side of a display device such as a liquid crystal display, and various input operations can be performed by making the input pen contact and move the cover member. When a glass substrate is used as the cover member of the pen input device, generally, since the surface of the glass substrate has small irregularities and is formed smoothly, when the input pen contacts and moves with the surface of the glass substrate, the pen tip slips, resulting in a poor writing feel.

[0005] For example, Patent Document 1 discloses a technique for improving the pen-operating feeling of an input pen in a pen input device: a resin layer (anti-glare layer) having irregularities is formed on the surface of a cover member made of an active energy ray-curable resin composition, and the average interval between the irregularities is 5 to 500 μm.

[0006] Prior Art Literature

[0007] Patent Literature

[0008] Patent Document 1: Japanese Patent Application Publication No. 2009-151476 Summary of the invention

[0009] Problem that the invention aims to solve

[0010] However, when the input pen is moved in contact with the surface of the cover member, the pen tip of the resin layer formed on the surface of the cover member is too stuck and difficult to slide, making it difficult to obtain a good pen-moving feel.

[0011] Therefore, the present invention provides a cover member for an input device and an input device that provide excellent pen-operating feeling of an input means such as an input pen.

[0012] Means for solving problems

[0013] The input device cover member and the input device that solve the above-mentioned problems have the following features.

[0014] That is, the input device cover member according to the present invention is an input device cover member arranged on the front side of a display device in an input device, at least one main surface of the input device cover member has projections and depressions, and in the main surface having the projections and depressions, when the cutoff value of the high-frequency filter λc is set to a value 1.6 times the spacing width of the projections and depressions of a measured cross-sectional curve and the cutoff value of the low-frequency filter λs is set to 25 μm, the maximum height width of the projections and depressions is 3 to 1000 nm and the spacing width of the projections and depressions is 50 to 1000 μm, and when the cutoff value of the high-frequency filter λc is set to 25 μm, the surface roughness (three-dimensional) arithmetic mean height Sa of the projections and depressions is 1 to 50 nm and the spacing width of the projections and depressions is 0.01 to 10 μm.

[0015] With such a configuration, the input means such as an input pen can be made neither too difficult nor too easy to slide for the operation of the input device, and the pen-operating feel of the input means such as the input pen can be made excellent.

[0016] Furthermore, the haze is less than 10% in the visible light wavelength range.

[0017] Thereby, the transparency of the input device cover member can be maintained, and the visibility of the display device can be maintained.

[0018] Furthermore, the input device includes the input device cover member described in the present application, a display device, and a detection circuit for detecting input.

[0019] This makes it possible to improve the pen-operating feeling of an input device such as an input pen.

[0020] Furthermore, the input device includes an input pen that performs input to the input device by moving while being in contact with the main surface of the input device cover member.

[0021] With such a configuration, it is possible to provide the input pen with an excellent pen-operating feel for the input device.

[0022] Effects of the Invention

[0023] According to the present invention, it is possible to improve the pen-operating feeling of an input device such as an input pen. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic side cross-sectional view showing an input device.

[0025] Figure 2 It is a diagram showing a measured cross-sectional curve of the main surface, concavities and convexities with a large interval width, and concavities and convexities with a small interval width.

[0026] Figure 3: is a graph showing the cutoff values ​​of the high-frequency filter λc and the low-frequency filter λs.

[0027] Figure 4 This is a diagram showing a state in which a pen tip is in contact with a main surface of a glass substrate having two types of large and small concavities and convexities formed thereon with different interval widths.

[0028] Figure 5 This is a diagram showing a state where a pen tip is in contact with a main surface of a glass substrate having two types of large and small concavities and convexities with different interval widths.

[0029] Description of Reference Numerals

[0030] 10 Input Devices

[0031] 20 Glass substrate

[0032] 20a Main surface

[0033] 30 Display components

[0034] 40 Digital Converter Circuit

[0035] 50 Input pen DETAILED DESCRIPTION

[0036] Next, the input device cover member according to the present invention and the mode for implementing the input device will be described with reference to the drawings.

[0037] Figure 1 The input device 10 shown is one embodiment of an input device including an input device cover member according to the present invention.

[0038] The input device 10 includes: a display element 30 for displaying an image; a glass substrate 20 as a cover member disposed on the front side of the display element 30; a digitizer circuit 40 disposed on the back side of the display element 30; and an input pen 50. The glass substrate 20 is an example of a cover member for the input device according to the present invention, and the digitizer circuit 40 is an example of a detection circuit for detecting input according to the present invention.

[0039] In addition, the "front side" of the display element 30 refers to the side where the image is displayed, and the "back side" of the display element 30 refers to the side opposite to the side where the image is displayed. Figure 1 In the figure, the “front side” of the display element 30 is the upper side of the paper, and the “back side” is the lower side of the paper.

[0040] The input device 10 can input characters, graphics, and the like by moving the 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, by moving the user's finger in contact with the glass substrate 20, characters, graphics, and the like can be input.

[0041] The input device 10 is, for example, a tablet terminal. The tablet terminal in a broad sense 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.

[0042] The glass substrate 20 is formed of a transparent glass plate having projections and depressions formed on at least one main surface 20a. As the glass substrate 20, for example, a glass plate made of aluminosilicate glass or borosilicate glass can be used. In the case where the glass substrate 20 is a glass plate made of alkali-containing aluminosilicate glass, the glass substrate 20 may also have a chemically strengthened layer on the surface. In addition, the details of the glass substrate 20 will be described later.

[0043] The glass substrate 20 is disposed on a surface on which the input pen 50 contacts the main surface 20 a on which the concavities and convexities are formed.

[0044] The digitizer circuit 40 includes a detection sensor that detects input by an input means such as an input pen 50 .

[0045] The input pen 50 is an input tool having a shape similar to a writing tool such as a pencil or a ballpoint pen, and the pen tip 51 in contact with the glass substrate 20 is made of a synthetic resin material such as an elastomer or polyacetal resin, or felt, etc. The pen tip 51 made of these components is easily caught by the uneven surface. Therefore, the pen movement feeling 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 formed with the uneven surface.

[0046] In this embodiment, although the glass substrate 20 is used as the input device cover member, the present invention is not limited thereto, and a resin substrate formed of a synthetic resin and having projections and depressions formed on at least one main surface may be used as the cover member. In this case, the projections and depressions of the resin substrate may be formed by, for example, performing a sandblasting process such as wet sandblasting on the main surface of the resin substrate or performing an embossing process on the main surface of the resin substrate.

[0047] In addition, a member having a resin layer with uneven surfaces formed on at least one main surface of a glass substrate can be used as a cover member. In this case, the cover member can be formed by attaching a resin sheet with uneven surfaces to 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 forming a synthetic resin mixed with powder particles into a sheet. Furthermore, the resin layer can also be formed by spraying the synthetic resin on the main surface of the glass substrate using a sprayer.

[0048] Among them, when the glass substrate 20 is used as the cover member, compared with the case of using a member having a resin layer formed on the main surface of a resin substrate or a glass substrate, since the surface hardness becomes higher, it is advantageous that scratches are less likely to be attached to the surface.

[0049] Next, the glass substrate 20 will be described.

[0050] The glass substrate 20 is one embodiment of the input device cover member according to the present invention.

[0051] The main surface 20 a of the glass substrate 20 has projections and depressions.

[0052] like Figure 2 As shown, the concavity and convexity are composed of two types of concavity and convexity with different intervals. The maximum height amplitude Rz of the concavity and convexity with a large interval amplitude is 3nm to 1000nm, and the interval amplitude RSm of the concavity and convexity is 50μm to 1000μm. In addition, the three-dimensional arithmetic mean height Sa of the concavity and convexity with a small interval amplitude is 1nm to 50nm, and the interval amplitude RSm of the concavity and convexity is 0.01μm to 10μm.

[0053] The maximum height width Rz is preferably larger than the three-dimensional arithmetic mean height Sa. Furthermore, the maximum height width Rz is preferably 1.1 to 500 times the three-dimensional arithmetic mean height Sa.

[0054] Here, in the concavity with a large interval width, the maximum height width Rz is the sum of the height of the highest peak and the depth of the deepest valley of the concavity, and the interval width RSm of the concavity is the average of the period lengths Xs of the concavity with a given reference length.

[0055] In addition, in the concave and convex with small interval width, the three-dimensional arithmetic mean height Sa is the average of the absolute values ​​of the height Z1 of the mountain and the depth Z2 of the valley of the concave and convex in a given three-dimensional area, and the interval width RSm of the concave and convex is the average of the period length Xs of the concave and convex with a given reference length.

[0056] like Figure 2 , Figure 3As shown, the values ​​of the maximum height amplitude Rz of the convex-concave with the above-mentioned large spacing amplitude and the spacing amplitude RSm of the convex-concave are obtained under the following conditions: the cutoff value λc1 of the high-frequency filter λc used to block the long wavelength component from the measured cross-sectional curve of the main surface 20a is set to a value 1.6 times the spacing amplitude of the convex-concave of the measured cross-sectional curve, and the cutoff value λs1 of the low-frequency filter λs used to block the short wavelength component from the measured cross-sectional curve of the main surface 20a is set to 25μm.

[0057] The values ​​of the three-dimensional arithmetic mean height Sa of the concavities and convexities with small interval width and the interval width RSm of the concavities and convexities are obtained when the cutoff value λc2 of the high-frequency filter λc for blocking long wavelength components from the measured cross-sectional curve of the main surface 20a is set to 25 μm.

[0058] In the measured cross-sectional curve of the main surface 20 a , the high-frequency filter λc having a cutoff value λc2 is applied to remove the undulation component and the large-width concavity and convexity components of the main surface 20 a , thereby obtaining a small-width concavity and convexity curve.

[0059] By making the concavo-convex shapes with large intervals and the concavo-convex shapes with small intervals in the main surface 20a of the glass substrate 20 fall within such a range, the visual recognition of the display element 30 can be maintained in the input device 10, and the pen-operating feeling of the input means such as the input pen 50 can be improved. In addition, the occurrence of glare called flicker caused by the interference of scattered light caused by the formed concavo-convex can be suppressed. Furthermore, if the resin layer is not formed on the main surface 20a of the glass substrate 20, but the concavo-convex shape is directly formed, the scratch resistance is high and scratches are difficult to adhere, so the visual recognition of the display element 30 will not be reduced.

[0060] The large-interval-width concavities and convexities have an influence on 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 parts of the large-interval-width concavities and convexities, but does not contact the concave parts of the large-interval-width concavities and convexities. Thus, by combining the moderate increase and decrease of the frictional force between the pen tip 51 and the main surface 20a, it is possible to prevent the excessive increase and excessive decrease of the frictional force between the pen tip 51 and the main surface 20a, and to make the pen-moving feeling based on the input pen 50 excellent. In addition, when the user's finger is moved in a state of contact with the glass substrate 20, the finger can also be moved moderately and smoothly, and the pen-moving feeling when performing finger-based input can be excellent. In this way, the pen-moving feeling of input means such as the input pen 50 and the finger can be improved.

[0061] The upper limit of the maximum height width Rz of the concavities and convexities with a large interval width is set to 1000 nm, but is preferably set to 500 nm, and more preferably set to 200 nm.

[0062] In addition, the lower limit of the maximum height width Rz of the concavities and convexities with a large interval width is set to 3 nm, but is preferably set to 4 nm, and more preferably set to 5 nm.

[0063] The upper limit of the interval width RSm of the concavo-convex with a large interval width is set to 1000 μm, preferably 900 μm, and more preferably 800 μm.

[0064] The small interval width of the concavoconvex helps to increase the friction between the main surface 20a of the glass substrate 20 and the pen tip 51. As a result, it is possible to prevent the pen tip 51 from slipping on the main surface 20a of the glass substrate 20, and to provide an excellent pen-moving feeling based on the input pen 50. In addition, when the user's finger is moved in contact with the glass substrate 20, the finger can be moved moderately and smoothly, and the pen-moving feeling when performing finger-based input can be excellent. In this way, the pen-moving feeling of input means such as the input pen 50 and fingers can be improved.

[0065] The upper limit of the three-dimensional arithmetic mean height Sa of the concavities and convexities with a small interval width is set to 50 nm, preferably 40 nm, and more preferably 30 nm.

[0066] The upper limit of the interval width RSm of the concavo-convex with a small interval width is set to 10 μm, but is preferably set to 7 μm, and more preferably set to 5 μm.

[0067] The lower limit of the interval width RSm of the concavo-convex with a small interval width is set to 0.01 μm, preferably 0.1 μm, and more preferably 0.5 μm.

[0068] Furthermore, the main surface 20 a of the glass substrate 20 provides particularly good writing feel for the pen tip 51 formed of a member that is easily caught by uneven surfaces such as the above-mentioned elastomer, resin materials such as polyacetal resin, and felt.

[0069] From the viewpoint of image visibility of the display element 30 when viewing the image through the glass substrate 20 , the glass substrate 20 is formed so that the haze, which is an index related to transparency and represents cloudiness, is less than 10% in the wavelength range of visible light (380 nm to 780 nm).

[0070] By setting the haze of the glass substrate 20 to less than 10%, the transparency of the glass substrate 20 can be maintained, and the visibility of the display element 30 can be maintained.

[0071] In the case of this embodiment, the haze of the glass substrate 20 is set to less than 10%, but is preferably less than 7%, more preferably less than 5%, and further preferably less than 4%.

[0072] Furthermore, an antireflection film for reducing the reflectivity of the side contacted by the input pen, or an antifouling film for preventing adhesion of fingerprints and imparting water repellency or oil repellency can be formed on the main surface 20 a of the glass substrate 20 .

[0073] When the glass substrate 20 is used as a cover member of the input device 10, an anti-reflection film is provided on at least the main surface 20a on the front side (the side contacted by the input pen 50) of the glass substrate 20. In addition, when there is a gap between the glass substrate 20 and the display element 30, it is preferred that an anti-reflection film is also provided on the main surface 20a on the back side (display element 30 side) of the glass substrate 20.

[0074] As the antireflection 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 relatively low refractive index film and a relatively high refractive index film are alternately stacked can be used. The antireflection film can be formed by sputtering or CVD.

[0075] When the main surface 20a of the glass substrate 20 has an anti-reflection film, the concave-convexity of the main surface 20a of the glass substrate 20 is formed so that the concave-convexity on the surface of the anti-reflection film is within the range of the above-mentioned surface roughness (the maximum height amplitude Rz of the concave-convexity with a large spacing amplitude and the spacing amplitude RSm of the concave-convexity, and the three-dimensional arithmetic surface height Sa of the concave-convexity with a small spacing amplitude and the spacing amplitude RSm of the concave-convexity).

[0076] In addition, when the main surface 20a of the glass substrate 20 has an anti-reflection film, the concavoconvexity of the main surface 20a of the glass substrate 20 is formed so that the haze of the glass substrate 20 having the anti-reflection film is within the above range. In addition, when the interval width RSm of the concavoconvexity and the three-dimensional arithmetic mean height Sa of the concavoconvexity are measured after the anti-reflection film is formed, a 10nm Au film is formed and these values ​​are measured.

[0077] When the glass substrate 20 is used as a cover member of the input device 10 , an antifouling film is provided on a main surface 20 a on the front side (the side with which the input pen 50 contacts) of the glass substrate 20 .

[0078] The antifouling 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 fluorine-containing water-repellent functional group in the side chain can be used. The fluorine-containing polymer can be synthesized, for example, by dehydration condensation of silanol.

[0079] When the main surface 20 a on the front side of the glass substrate 20 has an antireflection film and an antifouling film, the antireflection film is formed on the main surface 20 a of the glass substrate 20 , and the antifouling film is formed on the antireflection film.

[0080] In the case where the main surface 20a of the glass substrate 20 has an anti-fouling film, or in the case where the main surface 20a of the glass substrate 20 has an anti-reflection film and an anti-fouling film, the concavities and convexities on the main surface 20a of the glass substrate 20 are formed so that the concavities and convexities on the surface of the anti-fouling film are within the range of the above-mentioned surface roughness (the maximum height amplitude Rz of the concavities and convexities with a large spacing amplitude and the spacing amplitude RSm of the concavities and convexities, and the three-dimensional arithmetic surface height Sa of the concavities and convexities with a small spacing amplitude and the spacing amplitude RSm of the concavities and convexities).

[0081] In addition, when the main surface 20a of the glass substrate 20 has an anti-fouling film, or when the main surface 20a of the glass substrate 20 has an anti-reflection film and an anti-fouling film, the main surface 20a of the glass substrate 20 is formed with projections and depressions so that the haze of the glass substrate 20 after the anti-fouling film is formed, or the haze of the glass substrate 20 after the anti-reflection film and the anti-fouling film are formed, is within the above-mentioned range.

[0082] Next, a method for manufacturing the glass substrate 20 will be described.

[0083] The projections and depressions formed on at least one main surface 20 a of the glass substrate 20 are formed by combining at least one of treatment methods such as wet sandblasting, chemical etching, and silica coating treatment on the main surface 20 a.

[0084] Wet sandblasting is a process in which abrasive grains composed of individual particles such as aluminum oxide and a liquid such as water are uniformly stirred to form a slurry, and the resulting material is sprayed at high speed from a spray nozzle onto a workpiece composed of glass using compressed air, thereby forming fine concave and convex surfaces on the workpiece. Furthermore, as a nozzle for spraying the slurry, a round nozzle whose area of ​​the spray port of the slurry is reduced relative to the area of ​​the workpiece is used, and various surface shapes can be formed by making the round nozzle move relative to the workpiece.

[0085] In wet sandblasting, when the high-speed sprayed slurry hits the workpiece, the surface of the workpiece is cut, hit, or rubbed by the abrasive particles in the slurry, thereby forming fine concavoconvex on the surface of the workpiece. In this case, the abrasive particles sprayed onto the workpiece and the fragments of the workpiece cut by the abrasive particles are washed by the liquid sprayed onto the workpiece, so that the particles remaining in the workpiece are reduced. In addition, by making the nozzle scan arbitrarily relative to the workpiece and partially spraying the slurry on the surface of the workpiece, in addition to the concavoconvex with a small interval width, the concavoconvex with a large interval width can also be formed. The glass substrate 20 can be obtained by cutting a workpiece with two kinds of concavoconvex with different interval widths formed on the surface and modulating it into a desired size and shape.

[0086] The surface roughness of the small-interval concave-convex formed on the main surface of the workpiece by wet blasting can be adjusted according to the particle size distribution of the abrasive grains mainly contained in the slurry and the injection pressure when the slurry is sprayed on the workpiece. In addition, the maximum height width Rz of the large-interval concave-convex and the interval width RSm of the concave-convex can be adjusted according to the size of the nozzle spraying the slurry, the feed pitch width, and the injection pressure.

[0087] In wet blasting, when slurry is sprayed on the workpiece, the abrasive grains are transported to the workpiece by the liquid, so fine abrasive grains can be used compared to dry blasting, and the impact when the abrasive grains collide with the workpiece becomes smaller, so that precise processing can be performed. In this way, by performing wet blasting on the workpiece, it is easy to form two kinds of unevenness of appropriate size with different interval widths on the main surface 20a of the glass substrate 20, and the pen-operating feeling of the input means such as the input pen 50 can be excellent without damaging the transparency of the glass substrate 20.

[0088] In addition, in dry sandblasting, processing heat is generated in the workpiece due to friction when the ejected abrasive grains collide with the workpiece, but in wet sandblasting, the surface of the workpiece is always cooled by the liquid during the process, so the workpiece is not heated by the sandblasting. In addition, by performing dry sandblasting, it is also possible to form unevenness on the main surface 20a of the glass substrate 20, but in dry sandblasting, the impact when the abrasive grains collide with the main surface 20a of the glass substrate 20 is likely to be too large, so that the surface roughness of the main surface 20a formed with unevenness becomes too large, and the transparency of the glass substrate 20 is easily damaged.

[0089] The chemical etching process is a process of chemically etching the main surface 20 a of the glass substrate 20 using hydrogen fluoride (HF) gas or hydrofluoric acid.

[0090] The silica coating treatment is a treatment in which a coating agent is applied to the main surface 20 a of the glass substrate 20 and then heated. The applied coating agent contains a matrix precursor such as a silica precursor and a liquid medium that dissolves the matrix precursor.

[0091] Example

[0092] Next, an embodiment of the glass substrate 20 having two types of large and small concavo-convexities with different interval widths of concavo-convexities formed on the main surface 20 a will be described. However, the glass substrate 20 is not limited to this.

[0093] [Sample production]

[0094] In this example, samples 1 to 7 were prepared as examples of the glass substrate 20, and samples 8 and 9 were prepared as comparative examples. As the glass substrate 20 used in samples 1 to 9, alkali-containing aluminosilicate glass having a thickness of 1.1 mm was used.

[0095] By wet blasting the glass substrates 20 of the samples 1 to 7 of the embodiment, two types of concave-convex with different interval widths are formed on one main surface 20a. Specifically, the following wet blasting is performed on the glass substrates 20 of the samples 1 to 7: in the wet blasting, abrasive grains composed of aluminum oxide with a particle size of ♯4000 or #6000 and water are uniformly stirred to prepare a slurry, the glass substrate 20 is placed on a processing table, and the slurry prepared as described above is scanned and sprayed on the entire main surface 20a of the glass substrate 20 while moving a circular nozzle at a speed of 0.5mm / s using air with a processing pressure of 0.1 to 0.2MPa. The circular nozzle for wet blasting is a nozzle that reduces the cross-sectional area of ​​the slurry injection port relative to the area of ​​the main surface 20a and partially sprays the slurry on the main surface 20a. The interval width of the concave-convex with a large interval width can be changed by changing the scanning distance of the circular nozzle. In addition, the maximum height width Rz of the concave-convex with a large interval width can be changed by increasing the number of scans. The three-dimensional arithmetic mean height Sa of the concavities and convexities with a small interval width can be changed by changing the particle size of aluminum oxide or changing the processing pressure. As the abrasive grains, polygonal abrasive grains are used.

[0096] In samples 2 to 7, for the spacing width of the concave and convex with a large spacing width, the samples were prepared by making the scanning distance of the circular nozzle variable from 50 to 500 μm. For the maximum height width Rz of the concave and convex with a large spacing width, the samples were prepared by making the scanning number of the circular nozzle variable from 2 to 15 times that of sample 7. For the three-dimensional arithmetic mean height Sa of the concave and convex with a small spacing width, the samples were prepared by changing the particle size of aluminum oxide to #4000 to 6000 and increasing the processing pressure in the range of 0.1 to 0.2 MPa.

[0097] The main surface 20a of the glass substrate 20 of the sample 8 serving as the comparative example was not treated. That is, the glass substrate 20 of the sample 8 was untreated.

[0098] The glass substrate 20 of the comparative example sample 9 was subjected to wet blasting as follows: in the wet blasting, the slurry was uniformly sprayed on the entire surface of the main surface 20a by a wide nozzle at a processing pressure of 0.25 MPa. The wide nozzle for wet blasting is a nozzle that has a large width length of the slurry spraying port and can uniformly spray the slurry on the entire surface of the main surface 20a.

[0099] [Measurement of surface roughness]

[0100] The surface roughness of the main surface 20a of the glass substrate 20 was measured for samples 1 to 9. The surface roughness was measured for the main surfaces subjected to wet blasting for samples 1 to 7 and 9, and for sample 8, for one main surface 20a.

[0101] For bumps with large spacing, the measured surface roughness parameters are the maximum height amplitude Rz and the spacing amplitude RSm of the bumps. For bumps with small spacing, the measured surface roughness parameters are the three-dimensional arithmetic surface height Sa and the spacing amplitude RSm of the bumps. The surface roughness is measured using a white interference microscope.

[0102] The white interference microscope used was a white interference microscope (New View 7300) manufactured by Zygo Corporation, and the measurement was performed in accordance with JIS B0601-2013.

[0103] The measurement conditions for the large-interval concavity and convexity were implemented using a 2.5x objective lens and a 1x zoom lens, with a measurement area of ​​2827×2120μm, a camera pixel count of 640×480, and a cumulative count of 1. When measuring the maximum height width Rz of the large-interval concavity and the concavity and convexity interval width RSm, the cutoff value λc1 of the high-frequency filter λc was set to about 1.6 times the concavity and convexity interval width RSm, and the cutoff value λs1 of the low-frequency filter λs was set to 25μm.

[0104] The measurement conditions for the concavoconvex with small interval width were implemented using a 50x objective lens and a 2x zoom lens, with a measurement area of ​​74×55μm, a camera pixel count of 640×480, and a cumulative number of 8 times. The cutoff value λc2 of the high-frequency filter λc when measuring the three-dimensional arithmetic mean roughness Sa of the concavoconvex with small interval width and the interval width RSm of the concavoconvex was set to 25μm.

[0105] [Measurement results of surface roughness]

[0106] The results of measuring the surface roughness of Samples 1 to 9 will be described.

[0107] Table 1 shows the measurement results.

[0108] [Table 1]

[0109]

[0110] As shown in Table 1, the maximum height width Rz of the concavoconvex with large interval width is in the range of 10 nm to 151 nm for Samples 1 to 7 as Examples, and there is a tendency that the maximum height width Rz increases as the number of scans of the wet sandblasting process increases. Concavoconvex with large interval width is not formed for Sample 8 as the untreated comparative example and Sample 9 as the comparative example subjected to the wet sandblasting process using a wide nozzle.

[0111] The spacing width RSm of the large spacing concavo-convex was in the range of 51 μm to 520 μm for samples 1 to 7 of the examples. No large spacing concavo-convex was formed for sample 8 of the untreated comparative example and sample 9 of the comparative example subjected to wet blasting with a wide nozzle.

[0112] The three-dimensional arithmetic surface height Sa of the concavoconvex with a small interval width is in the range of 4.0nm to 7.5nm for samples 1 to 7 of the embodiments. For sample 8 as an untreated comparative example, it is 0.2nm smaller than samples 1 to 7, and for sample 9 as a comparative example subjected to wet sandblasting with a wide nozzle, it is 7.0nm.

[0113] [Measurement of haze]

[0114] The haze was measured for samples 1 to 9. The haze was measured using an ultraviolet-visible-near-infrared spectrophotometer (UV-3100PC) manufactured by Shimadzu Corporation in accordance with JIS K7361-1-1997.

[0115] [Measurement results of haze]

[0116] As shown in Table 1, the haze of Samples 1 to 7 of Examples was in the range of 0.7% to 3.6%, which was not significantly different from that of the untreated Sample 8 and the Sample 9 subjected to the wet blasting treatment using a wide nozzle.

[0117] [Evaluation of visual recognition]

[0118] The visibility of the image displayed on the display element 30 was evaluated when the glass substrates 20 of samples 1 to 9 were placed on the front side of the display element 30 of the input device 10. As an evaluation method, whether the image displayed on the display element 30 was visible was evaluated in the following three stages.

[0119] ◎: A clear image can be seen, and no penetration can be seen in the image;

[0120] ○: Although the image can be visually recognized sufficiently, only a little image penetration is seen;

[0121] ×: The image is not clear, and image bleeding is noticeable.

[0122] [Evaluation results of visual recognition]

[0123] As shown in Table 1, regarding the image visibility, Samples 1 to 7 as Examples were rated ◎, Sample 8 as an untreated Comparative Example was rated ◎, and Sample 9 as a Comparative Example subjected to wet blasting with a wide nozzle was rated ◎.

[0124] [Evaluation of the brushwork experience]

[0125] The sensory test was used to evaluate the pen-operating feeling when inputting characters and graphics on the glass substrate 20 using the input pen 50. As the evaluation method, a pro pen (KP-503E) manufactured by Wacom was used as the input pen 50, and a total of 20 men and women in their 20s to 50s were asked to rate the pen-operating feeling on the glass substrate 20 in seven levels from "very good writing feeling" to "very bad writing feeling", and the evaluation was performed using the average score.

[0126] [Evaluation results of pen-handling experience]

[0127] As shown in Table 1, regarding the pen-handling feeling, samples 1 to 7 as examples were 4.1 or more, and sample 8 as an untreated comparative example and sample 9 as a comparative example subjected to wet blasting with a wide nozzle were 3.9 or less.

[0128] [Comprehensive evaluation of each sample]

[0129] As shown in Table 1, Figure 4 As shown, for samples 1 to 7 that serve as embodiments, by forming two types of unevenness with different sizes of intervals between appropriate unevenness formed on the main surface 20a to which the pen tip 51 of the input pen 50 contacts, it is possible to suppress the pen tip 51 from slipping on the main surface 20a of the glass substrate 20, and by combining a moderate increase and decrease in the frictional force between the pen tip 51 and the main surface 20a, a good evaluation result of a good pen-handling feel and visual recognizability of ◎ can be obtained.

[0130] On the other hand, in Sample 8 which is an untreated comparative example, the main surface 20 a to which the input pen 50 contacts has small irregularities and is easy to slip, so the pen-operating feeling is poor.

[0131] In addition, if Figure 5 As shown, in Sample 9 as a comparative example subjected to wet blasting using a wide nozzle, since there are no two types of unevenness with different interval widths, the pen tip 51 is too difficult to slide and gets stuck, resulting in poor pen handling feel.

[0132] Industrial Availability

[0133] The present invention can be used in an input device that can use an input pen or other input means to input text, graphics, etc., and an input device cover member possessed by the input device. In particular, it can be used in an input device cover member that is arranged on the front side of a display device of the input device and has a concave-convex shape on at least one main surface, and an input device possessing the input device cover member.

Claims

1. A cover member for an input device, arranged on the front side of a display device in an input device, characterized in that: In the input device cover member, At least one main surface has unevenness, In the main surface having the concavo-convex, when the cutoff value of the high-frequency filter λc is set to 1.6 times the interval width of the concavo-convex of the measured cross-sectional curve and the cutoff value of the low-frequency filter λs is set to 25 μm, the maximum height width of the concavo-convex is 3 to 1000 nm. When the cutoff value of the high-frequency filter λc is set to 25 μm, the three-dimensional arithmetic mean roughness Sa of the concavities and convexities is 1 to 50 nm.

2. The cover member for an input device according to claim 1, wherein: In the main surface having the irregularities, when the cutoff value of the high frequency filter λc is set to 1.6 times the irregularity interval width of the measured cross-sectional curve and the cutoff value of the low frequency filter λs is set to 25 μm, the irregularity interval width is 50 to 1000 μm.

3. The cover member for an input device according to claim 1, wherein: In the main surface having the above-mentioned concavities and convexities, when the cutoff value of the high-frequency filter λc is set to 25 μm, the interval width of the concavities and convexities is 0.01 to 10 μm.

4. A cover member for an input device, arranged on the front side of a display device in the input device, characterized in that: In the input device cover member, At least one main surface has unevenness, In the main surface having the concavoconvexities, when the cutoff value of the high-frequency filter λc is set to 1.6 times the interval width of the concavoconvexities of the measured cross-sectional curve and the cutoff value of the low-frequency filter λs is set to 25 μm, the interval width of the concavoconvexities is 50 to 1000 μm. When the cutoff value of the high-frequency filter λc is set to 25 μm, the interval width of the concavoconvexity is 0.01 to 10 μm.

5. The cover member for an input device according to claim 4, wherein: On the main surface having the irregularities, when the cutoff value of the high-frequency filter λc is set to 1.6 times the interval width of the irregularities of the measured cross-sectional curve and the cutoff value of the low-frequency filter λs is set to 25 μm, the maximum height width of the irregularities is 3 to 1000 nm.

6. The cover member for an input device according to claim 4, wherein: In the main surface having the above-mentioned concavities and convexities, when the cutoff value of the high-frequency filter λc is set to 25 μm, the three-dimensional arithmetic mean roughness Sa of the concavities and convexities is 1 to 50 nm.

7. The input device cover member according to any one of claims 1 to 6, wherein: The haze is less than 10% in the visible light wavelength range.

8. An input device, characterized in that: have: An input device cover member according to any one of claims 1 to 7; a display device; and a detection circuit for detecting input.

9. The input device according to claim 8, characterized in that The input device includes an input pen that performs input to the input device by moving while in contact with a main surface of the input device cover member.

Images