JP2015022744A - Touch panel stain prevention structure and fingerprint stain prevention film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To inhibit interference fringes from occurring in the case of being applied to a dot matrix type display device in a stain prevention structure with thin lines provided on a touch panel surface.SOLUTION: An operation surface of a touch panel includes thin lines running in parallel with the surface, a line width dimension of the thin lines in a parallel direction to the touch panel surface is less than 1/3 of the dot size of a dot matrix display device, an opening ratio represented by a ratio of the area of an open part where the thin lines are not shaded on a visible surface of the display device to the area of the visible surface is equal to or more than 60%, and the shape of the thin lines is a polygonal line or a curve so as to reduce interference fringes that occur between a dot array of the display device and an array of the thin lines.

Description

  The present invention relates to a touch panel stain prevention structure for preventing dirt such as fingerprints and sebum from adhering to the touch panel surface integrated with a dot matrix type display device, and a fingerprint stain prevention film manufactured by the stain prevention structure. And about.

  When compared with a conventional mechanical switch device, an operation device that combines a known dot matrix type display device such as liquid crystal or organic EL and a known touch panel can arbitrarily set an operation screen. It is widely used as an excellent HMI (Human Machine Interface) because it can be operated intuitively and can easily operate devices having complicated functions.

  As such a touch panel operation detection sensor, a method of detecting a pressing position on the display device by detecting a pressing force of a finger to be operated and detecting it as an operation position coordinate, and a matrix shape provided on the surface of the display device The position of the operation finger is specified by electrically detecting the capacitance value formed by the XY transparent electrode pair, or the operation finger position is detected by the LED and the light receiving element installed on the opposite side of the display device. However, any of these methods functions on the premise that an operation finger contacts the surface of the touch panel.

  The touch panel may be formed independently from the display device and attached to the surface of the display device, or may be integrated into the pixels constituting the display device (in-cell method).

  In either the touch panel formed independently of the display device or the integrated touch panel, the touch panel surface is directly operated with a finger during operation input, so that fingerprints or sebum dirt adheres to the touch panel surface. The appearance of the display device is inevitably deteriorated. Furthermore, even in a simple liquid crystal display device or the like that does not include a touch panel, fingerprints and sebum stains are also a problem due to the fact that the surface of the liquid crystal display device is easily touched, especially in a small portable information terminal. It is known.

  In order to solve the above problem, a technique has been proposed in which a thin black line is arranged on the surface of the touch panel to prevent the operation finger from directly touching the touch panel surface and to reduce the adhesion of the fingerprint.

  Japanese Utility Model Publication No. Sho 63-116675   Japanese Utility Model Publication No. 61-172388

  However, although both Patent Document 1 and Patent Document 2 disclose disposing black thin lines on the surface of the glass constituting the touch panel and making it difficult to see the fingerprint traces, the thin lines are disclosed to the display device. There is no suggestion or disclosure regarding the problem of visibility and how to solve it.

By the way, in general, a linear pattern A arranged at a specific arrangement interval (position period) and a linear pattern B drawn by an arrangement interval that is slightly different from the pattern A overlap. In addition, it is known that a stripe pattern that does not originally exist is generated as an interference fringe. Specifically, for example, in the example of FIG. 6A, when the pattern A composed of fine lines arranged at a predetermined period and the pattern B composed of fine lines slightly different in pitch are overlapped, the period P It can be seen that a striped pattern is produced.
In another example, when a pattern C and a pattern D formed by lines drawn at a predetermined pitch as shown in FIG. 6B are overlapped at an arbitrary angle, an originally impossible vertical stripe pattern appears as an interference fringe.

Similarly, since the dot matrix type display device is configured by arranging extremely small display pixels in a matrix, the display pixels are arranged on the display device at a predetermined pitch having a position periodicity at equal intervals. The Therefore, when a light-shielding fine line having a positional periodicity is pasted on a surface of this type of display device at a predetermined pitch, a stripe pattern as shown in FIG. 7 is generated as an interference fringe.
FIG. 7 is a photographic image in the case where a light-shielding mesh having thin lines with a thickness of 25 μm is pasted on a screen displaying black characters on a white background on a liquid crystal screen of a personal computer. It shows a state of being pasted in a direction that coincides with the matrix arrangement. Thus, it can be seen that a striped pattern is generated in the background color which should originally be white.

  Further, in the touch panel of the type that electrically detects the capacitance value, the fine wire is sandwiched between the XY electrode and the fingertip, thereby increasing the distance between the XY electrode and the fingertip. The sensitivity of the detected capacitance may decrease. In this regard, Patent Document 2 states that the sensitivity is not lowered by employing a dielectric thin wire. However, since the relative dielectric constant of the dielectric resin material is generally as small as 2, the sensitivity reduction is inevitable.

  The present invention has been made in view of the above-described problems, and the position periodicity of the pixel arrangement of the dot matrix and the arrangement of the fine lines in the anti-smudge structure having fine lines on a dot matrix type display device. Providing a dirt prevention structure that prevents interference fringes from occurring with the position periodicity and that does not decrease sensitivity even when used for a capacitive touch panel. An object of the present invention is to provide an antifouling fingerprint smearing film.

  The touch-panel antifouling structure of the present invention comprises a thin line that runs parallel to the surface of the touch panel, and the line width dimension of the thin line in the direction parallel to the touch panel surface is 1 / dot size of the dot matrix display device. And the aperture ratio of the fine line (the portion not shielded by the fine line, that is, the ratio of the area of the opening and the area of the visible surface of the display device) is 60% or more and the shape of the fine line is a broken line or Curved.

  In one aspect of the touch panel stain prevention structure of the present invention, the touch panel is provided with fine lines printed on the surface of the light-transmitting substrate.

  In one aspect of the touch panel antifouling structure of the present invention, the touch panel is provided with fine wires made of a metal material formed on the surface of the light-transmitting substrate.

  In one aspect of the touch panel antifouling structure of the present invention, the touch panel is provided with a thin line made of the metal material having a broken line shape removed at a predetermined interval.

  In one aspect of the touch panel antifouling structure of the present invention, the touch panel is provided with fine wires made of an ultrafine fiber material formed on the surface of the light-transmitting substrate.

  In one aspect of the touch panel antifouling structure of the present invention, the touch panel is provided with a substantially black thin line.

  In one aspect of the touch panel antifouling structure of the present invention, the surface is configured to include a thin line of substantially transparent color that has been antiglare-treated.

  In one aspect of the touch-panel antifouling structure of the present invention, the fine line has a height dimension formed on the visible surface of the display device, so that the visible angle of the display device is limited to provide a known peeping prevention function. It is configured as follows.

  In one aspect of the anti-stain structure of the touch panel of the present invention, the fingerprint stain is formed by forming the fine line on the surface of the light-transmitting resin film and applying a peelable adhesive to the back surface of the light-transmitting resin film. Configured as a prevention film.

  In one aspect of the anti-stain structure of the touch panel of the present invention, a thin line integrally formed with the resin film is provided on the surface of the light transmissive resin film.

  According to the touch panel contamination prevention structure of the present invention, the operation surface of the touch panel is provided with a thin line that runs parallel to the operation surface, and the line width of the thin line is less than 1/3 of the dot size in a dot matrix type display device. Since the aperture ratio of the fine lines (the portion not shielded by the fine lines, that is, the ratio of the area of the aperture and the area of the visible surface of the display device) is 60% or more, and the fine lines are arranged as broken lines or curves, Interference fringes are not generated between the arranged dot matrix and the thin lines, and the display luminance of the display device is hardly lowered. However, it is possible to realize a touch panel anti-stain structure that prevents the finger from smearing by touching the touch panel surface directly with the fine line, and at the same time, the display quality is not deteriorated due to interference fringes and luminance reduction.

  Moreover, according to the touch-panel antifouling structure of the present invention, since the fine wire is printed on the surface of the light-transmitting substrate, the structure can be mass-produced at low cost.

  Moreover, according to the touch-panel dirt prevention structure of this invention, since the said thin wire was mentioned as the metal material, the fall of the operation sensitivity in a capacitive touch panel does not raise | generate.

  In addition, according to the touch panel contamination prevention structure of the present invention, the thin line is a metal material having a broken line shape that is removed at predetermined intervals. There is no cause.

  In addition, according to the touch panel antifouling structure of the present invention, since the fine wire is an ultrafine fiber material formed on the surface of the light-transmitting substrate, a highly strong fine wire structure can be realized at low cost.

  In addition, according to the touch panel antifouling structure of the present invention, since the fine line is substantially black, there is no problem that the fine line reflects external light on the surface of the display device and the display becomes difficult to see.

  In addition, according to the touch panel antifouling structure of the present invention, since the fine line is a known anti-glare-processed substantially transparent color, the fine line reflects external light on the display device surface, making it difficult to see the display. There is no problem said.

  In addition, according to the touch panel contamination prevention structure of the present invention, the visible angle of the display device can be limited by the height dimension formed on the visible surface of the touch panel, so that a known peeping prevention function can be easily realized. can do.

  In addition, according to the fingerprint antifouling film of the present invention, the fine line is formed on the surface of the light transmissive resin film, and the adhesive that can be peeled off is applied to the back surface of the light transmissive resin film. It is suitable as an antifouling fingerprint antifouling film for tablet PCs and the like.

  Also, according to the fingerprint stain prevention film of the present invention, the fine wire is formed integrally with the resin film on the surface of the light-transmitting resin film, so that a very inexpensive fingerprint stain prevention film is provided. Can do.

  It is the figure showing the example of arrangement | positioning of the thin line in the touch-panel dirt prevention structure based on embodiment of this invention.   It is a figure explaining the structure of the dot matrix display apparatus based on embodiment of this invention.   It is the figure showing the example of arrangement | positioning of the thin line in the touch-panel dirt prevention structure based on embodiment of this invention.   It is the figure showing the example of arrangement | positioning of the thin line in the touch-panel dirt prevention structure based on embodiment of this invention.   It is a figure showing the example of arrangement | positioning of the thin wire | line in the touch-panel dirt prevention structure based on embodiment of this invention.   It is a figure explaining an interference fringe.   It is a photographic image which shows the interference fringe at the time of sticking an orthogonal mesh fine wire on a dot matrix liquid crystal display screen.   It is the figure explaining the reason which produces an interference fringe by the combination of a dot matrix display apparatus and an orthogonal mesh fine wire.   It is a figure showing the arrangement | positioning cross section of the touchscreen and thin wire | line in the touchscreen dirt prevention structure based on embodiment of this invention.   It is a figure explaining the peep prevention function in the touch-panel dirt prevention structure based on embodiment of this invention.   It is a figure explaining the fingerprint dirt prevention film which comprised the touchscreen dirt prevention structure of this invention to the light-transmitting film with an adhesive.   It is a figure explaining the fingerprint stain | pollution | contamination prevention film of the touchscreen provided with the thin line | wire integrally molded with the light transmissive resin film.

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.
1 shows a structure for preventing touch panel contamination according to an embodiment of the present invention. Reference numeral 1 denotes a state in which a touch panel 1b made of a light-transmitting material is attached to the surface of a known liquid crystal display device 1a (hereinafter abbreviated as display device 1). 10 represents a dot, which is the minimum unit of display pixels constituting the liquid crystal display device, surrounded by a matrix-like broken line. Reference numeral 20 denotes a thin line of thick film paste formed by printing on the surface of the touch panel 1b, for example, glass powder or the like kneaded in a liquid organic binder. The print formation method is not limited to this, and various printing methods may be applied.

  The arrangement of the thin lines 20 is a shape in which curves and straight lines are randomly combined as shown in 20a and 20b.

  As shown in FIG. 8, in the display device 1, the dots 10 constituting the dot matrix type display device 1 are regularly arranged, that is, arranged on the surface of the display device 1 with positional periodicity. On the other hand, when the thin line 20d or the thin line 20e is formed by orthogonal thin lines arranged regularly at a pitch slightly different from the arrangement pitch of the dots 10 as in the dot arrangement, the black lines in FIG. The portion 30 is a portion where the dot 10 and the thin line 20d or 20e completely overlap, and the other portion is in an incomplete overlapping state.

  In this case, the portion indicated by 30 in FIG. 8 becomes a dark portion in the position period on the visible surface of the display device 1 and becomes an interference fringe.

  On the other hand, when the arrangement of the thin lines 20d and 20e is arranged with a declination in the direction of 45 degrees (not shown) with respect to the arrangement of the dots 10, the interference fringes are not linear as shown in FIG. Instead, it occurs as a pattern such as a spot (not shown) on the display screen of the display device 1.

However, according to the embodiment of the present invention of FIG. 1, the shape of the thin line 20 is a combination of a curved line or a broken line, and therefore the arrangement of the thin line 20 does not have periodicity of the arrangement position in the surface direction of the display device 1. Accordingly, no interference fringes are generated between the dots 10 and the thin lines 20 due to the difference in the arrangement position period, so that the display screen quality of the display device 1 is good.
Further, even if the mounting direction of the thin wires 20 is changed with respect to the arrangement of the dots 10, in other words, even when the thin wires 20 are formed and pasted on a separate member from the display device 1, the pasting is performed. It is possible to eliminate the possibility of occurrence of interference fringes due to displacement.

  Next, in FIG. 1, when the thin line 20 is made light-shielding, the display screen of the display device 1 is shielded from light, which may cause a reduction in luminance of the display screen. Therefore, as a result of experiments by the inventor, in the touch panel antifouling structure of the present invention, the area shielded by the thin wires 20 is 40% of the display screen area of the display device 1, that is, the so-called aperture ratio is 60%. Thus, it was found that the luminance reduction was at an acceptable level. This means, for example, an aperture ratio equal to that when a plurality of light-shielding thin wires having a width of 20 μm are arranged with an interval of 100 μm. Therefore, it is desirable to maintain the light emission luminance of the display device 1 by setting the aperture ratio to 60% or more.

  Further, since the known dot matrix type display device is generally intended for color display, the structure of the display device is a matrix arrangement of size W × H, as shown by a broken line circle portion 11 in FIG. Color filters R (red), G (green), and B (blue) are provided in areas 101, 102, and 103 obtained by dividing the square dot 10 into three, and the divided areas 101 to 103 are controlled to be turned on and off independently. It can be done.

  Therefore, the width dimension of the divided areas 101 to 103 is 1/3 of the width dimension of the dot 10. However, since the thin line 20 in the touch panel antifouling structure of the present invention needs to prevent light emission of each of the divided pixels as much as possible, the width of the thin line 20 is, for example, as shown in FIG. The dimension is less than 101. That is, the width dimension of the thin line 20 in the display surface direction of the display device 1 is preferably less than 1/3 of the width dimension W constituting the dot 10.

  In recent years, in order to improve the light emission luminance of the liquid crystal display device, the dot 10 has a W (white) light emitting region in addition to the R, G, and B divided regions and is divided into a total of four. May be taken. In this case, it goes without saying that the width dimension of the thin wire 20 is preferably ¼ or less of the width dimension W of the dot 10.

  Next, the arrangement shape of the thin wires 20 in the touch panel contamination prevention structure of the present invention may be a geometric pattern as shown in FIGS. In this case, for example, according to the arrangement shown in FIG. 4, a portion where the dot 10 and the thin line 20 completely overlap periodically occurs as the black portion 30. However, the state of the overlapping portion 30 is not a continuous straight line as seen in FIG. This means that the area of the light-shielding portion that causes the stripe pattern is much smaller than that of the example of FIG. 8, and therefore the degree of visible interference fringes is reduced in the embodiments of FIGS. 3 to 5. Can be very small.

  In addition, the thin wire 20 in the touch panel antifouling structure of the present invention may be a metal material. Since the metal material generally has high strength, it is possible to increase deterioration resistance such as disconnection, peeling, and abrasion caused by rubbing the thin wire 20 disposed on the operation surface of the touch panel with an operation finger or the like. In this case, it goes without saying that the fine wire made of a metal material can generally be formed by performing an etching process in addition to known sputtering, plating, vapor deposition, thin film adhesion, and the like.

  FIG. 9A shows the arrangement of the substrate 50 made of, for example, transparent glass, the XY electrodes 51 disposed on the back surface of the substrate 50, and the fine wires 20 of the touch panel in the touch panel contamination prevention structure of the present invention. A cross-sectional view is shown. Thus, by arranging the thin wire 20 on the surface of the base material 50, the gap formed by the XY electrode 51 and the operation finger 3 becomes D0. The value of the capacitance formed by the finger 3 and the XY electrode 51 decreases, and the detection sensitivity of the operating finger 3 decreases.

  On the other hand, when the thin wire 20 is made of an electrically conductive metal material, the potential of the fingertip 3 becomes equal to the surface potential of the base member 50, so that the gap is equivalently shown in FIG. As shown, it becomes D1 and can be the same as the thickness of the substrate 50, so that the detection sensitivity does not decrease.

  However, the fact that the fine wire 20 is electrically conductive means that the capacitance value formed by the fine wire 20 and the XY electrode 51 can be determined by touching any part in the left-right direction in FIG. Since it does not change, there arises a problem that the position of the operation finger 3 cannot be determined.

  Therefore, the thin wire made of the metal material used in the touch panel antifouling structure of the present invention is formed from the metal material at a predetermined pitch P smaller than the arrangement interval of the XY electrodes 51 as shown in FIG. The thin wire 20 formed was partially etched away. Thus, by making the thin wire 20 made of the metal material into a broken line shape by partially etching away, the potential of the operating finger 3 can be made equal to the surface potential of the substrate 50 and the operating finger 3 is touching. Since it is possible to eliminate the capacitance between the operating finger 3 and the XY electrode 51 at a portion where there is not, the position of the operating finger 3 can be detected correctly without deteriorating the detection sensitivity. .

  Further, the fine wire in the touch panel antifouling structure of the present invention may be an ultrafine fiber material. Since this type of ultrafine fiber material is used in many markets as microfibers and micromesh, it is possible to realize a low-cost touch panel contamination prevention structure.

  In the embodiment using the fine wire made of the metal material, the fine wire is partially removed to form a broken line shape. However, in the case of the fine wire of the ultra fine fiber material according to the embodiment, the fiber material Even if the surface is partially subjected to conductive metal plating, it is an easily conceivable phenomenon that the problem of preventing the detection sensitivity from being lowered and the erroneous detection of the operating finger position are eliminated as described above.

  By the way, according to the touch-panel antifouling structure of the present invention, there is a possibility that the visibility of the display device 1 deteriorates due to the thin wires 20 arranged on the surface of the touch panel reflecting external light. Therefore, as a best embodiment, the fine wire 20 is made substantially black to prevent reflection of external light, or the fine wire 20 is made substantially transparent and a known anti-glare treatment is applied to the surface of the fine wire 20. desirable. Thereby, since the said thin wire | line 20 does not reflect external light, the visibility of the said display apparatus 1 does not deteriorate.

  Next, according to the touch panel contamination prevention structure of the present invention, the so-called viewing angle of the display device 1 can be adjusted by adjusting the height of the thin line 20 on the surface of the touch panel 1b in the display device 1. . That is, as shown in FIG. 10, the viewing angle is limited to θ by the height of the thin lines 20 formed on the surface of the touch panel 1b and the arrangement interval of the thin lines 20. As a result, the visible range of the display device 1 becomes narrow, and when viewed from a person other than the operator, the display image of the display device 1 cannot be viewed, so that a peep prevention effect can be achieved.

  FIG. 11 shows an embodiment of a fingerprint antifouling film 100 for a touch panel comprising the touch panel antifouling structure of the present invention. Reference numeral 111 denotes a light-transmitting resin film made of, for example, a PET film, and the thin wire 20 is formed on the operation surface side of the film 111. A peelable adhesive 112 made of, for example, a silicon resin is disposed on the back side of the film 111. The fingerprint antifouling film 100 is attached to a liquid crystal display screen of an existing smartphone or the like as a retrofit to reduce fingerprint adhesion to the liquid crystal display screen.

  FIG. 12 shows a cross-sectional shape of the fingerprint antifouling film 100 in which the light transmissive resin film 111 and the fine wire 20 are integrally formed. The thin wire 20 in this embodiment is pressure-molded at the same time as the film 111 is formed, and does not require a special process for forming the thin wire 20 as in the other embodiments. A prevention film can be provided.

  In the touch panel contamination prevention structure of the present invention, regardless of the presence or absence of the touch sensor function, fingerprints, sebum, or similar stains via the operation fingers adhere to the surface of the liquid crystal or similar dot matrix type display device. This is effective for the purpose of preventing the occurrence of such a phenomenon, and enables the fingerprint antifouling film to be supplied at a low cost.

  Furthermore, the touch panel contamination prevention structure of the present invention is not limited to a touch panel equipped with a display device, but touches a human body in, for example, a glass showcase, an interior decoration part made of a plating material, or an interior decoration part of an automobile. This technique is useful in that it prevents fingerprint smudges caused by the phenomenon.

1: display device, 1a: liquid crystal display device, 1b: touch panel, 3: operating finger, 10: dot, 20: fine line, 101-103: divided area, 30: dark part, 50: substrate, 51: XY electrode 111: Light transmissive film, 112: Adhesive material

Claims (10)

  Anti-stain structure that prevents dirt such as fingerprints and sebum from adhering to the surface of the touch panel integrated with the dot matrix type display device. The touch panel has a thin line that runs parallel to the surface of the touch panel. The line width dimension of the thin line in the direction parallel to the touch panel surface is less than 1/3 of the dot size of the dot matrix display device, and the area of the opening where the thin line does not shield on the visible surface of the display device; The aperture ratio represented by the ratio to the area of the visible surface is 60% or more, and the shape of the fine line is reduced in order to reduce interference fringes generated between the dot arrangement of the display device and the fine line arrangement. An anti-stain structure for a touch panel, wherein is a broken line or a curved line.   2. The touch panel contamination preventing structure according to claim 1, wherein the fine line is printed on the surface of a light-transmitting substrate.   2. The touch panel contamination preventing structure according to claim 1, wherein the thin line is a metal material formed on a surface of the light transmissive substrate.   4. The touch panel contamination preventing structure according to claim 3, wherein the thin line is a metal material having a broken line shape removed at a predetermined interval.   The touch-panel antifouling structure according to claim 1, wherein the fine wire is an ultrafine fiber material formed on a surface of a light-transmitting substrate.   6. The touch panel contamination prevention structure according to claim 1, wherein the thin line is substantially black.   6. The touch panel contamination preventing structure according to claim 1, wherein the thin line has a substantially transparent color in which a surface of the thin line is antiglare-treated.   8. The peek prevention function according to claim 1, wherein the fine line has a height dimension formed on a visible surface of the touch panel to limit a visible angle of the display device to provide a peep prevention function. Described structure for preventing touch panel contamination.   9. The structure according to claim 1, wherein the fine wire is formed on the surface of the light transmissive resin film, and a pressure sensitive adhesive is applied to the back surface of the light transmissive resin film. Touchscreen fingerprint stain prevention film.   The structure according to any one of claims 1, 6, 7, and 8, wherein a thin wire integrally formed with the resin film is provided on a surface of the light transmissive resin film. Touchscreen fingerprint stain prevention film.