JP2010086236A - Touch panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a capacitance detection type touch panel in which an uneven region is formed on the operation surface of the touch panel to prevent touch errors. <P>SOLUTION: The capacitance detection type touch panel includes: a transparent protective substrate 2 having an operation surface 1 where a plurality of touch recessed parts 1a including recessed curve surface are formed and an opposite surface on the opposite side to the operation surface 1 where recessed parts 1b provided while being made to correspond to the plurality of touch recessed parts 1a are formed; a transparent touch panel substrate 4 which is placed oppositely to the protective substrate 2 and includes a touch detection electrode 3 formed by a transparent conductive film; and a dielectric layer 15 which is placed while being made to correspond to the plurality of touch recessed parts 1a on the operation surface 1 between the protective substrate 2 and the touch panel substrate 4 and has a specific dielectric constant different from the protection substrate 2. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a touch panel.

  A display device in which a touch panel is mounted on the surface of a CRT or liquid crystal display as an input means is widely used in PDAs, portable game machines, ticket vending machines, ATMs, and the like. The touch panel detects a change in capacitance or resistance generated in an electrode disposed on the back side of the operation surface by touching the flat operation surface with a finger or an input pen, and determines a touch position.

JP2007-172142A

  Since the operation surface of the touch panel described above is flat, when an input is performed with a finger or the like while viewing from an oblique direction, parallax occurs between the touch panel and the display unit, and mistouch occurs. If a concave or convex portion is provided on the operation surface to prevent mistouch, the distance between the touch panel electrode and the finger or input pen on the operation surface changes in the capacitance detection type touch panel. There is a problem that it is difficult to determine the presence or absence of touch because the capacitance between the finger and the like changes at the concave portion or the convex portion.

  An object of the present invention is to provide a touch panel having an uneven shape on the operation surface.

The capacitance detection type touch panel according to claim 1 of the present invention includes:
An operating surface on which at least one first curved surface is formed, and a thickness that defines the thickness of the portion on the opposite side of the operating surface corresponding to the first curved surface, on which the first curved surface is formed. A transparent protective substrate having an opposing surface provided with two curved surfaces;
A transparent substrate disposed opposite to the protective substrate and provided with an electrode made of a transparent conductive film;
A dielectric layer disposed between the second curved surface of the protective substrate and the substrate in correspondence with the first curved surface of the operation surface, and having a relative dielectric constant different from that of the protective substrate;
It is provided with.

  According to a second aspect of the present invention, in the capacitance detection type touch panel according to the first aspect, the second curved surface formed on the opposite surface of the protective substrate and the dielectric layer are dielectric with respect to the electrodes on the substrate. In accordance with the shape of the first curved surface, the second curved surface of the first curved surface is set to have substantially the same capacitance on the surface of each part of the first curved surface located through the layer and the protective substrate. The shape and the dielectric constant of the dielectric layer and the protective plate are set.

  According to a third aspect of the present invention, in the capacitance detection type touch panel according to the first aspect, the second curved surface formed on the opposing surface of the protective substrate is the first curved surface of each portion of the operation surface. The protection substrate and the dielectric layer are substantially equal to each other in the combined value of the capacitance generated by the protection substrate having a relative dielectric constant and the dielectric layer having the second dielectric constant. The dielectric constant relative permittivity according to claim 4 is characterized in that the thickness is formed as a concave curved surface whose shape is changed according to the first curved surface of the operation surface. The first curved surface formed on the operation surface of the protection plate in the capacitance detection type touch panel is a convex portion protruding from the operation surface, and is a dielectric disposed between the second curved surface of the protection substrate and the substrate. The body layer has a dielectric constant greater than that of the protective substrate. Characterized by comprising the substance.

  According to a fifth aspect of the present invention, in the capacitance detection type touch panel according to the first aspect, the second curved surface formed on the operation surface of the protective substrate is a concave curved surface formed in a shape recessed from the operation surface. Thus, the dielectric layer disposed between the second curved surface of the protective substrate and the substrate is made of a dielectric material having a relative dielectric constant smaller than that of the protective substrate.

  According to a sixth aspect of the present invention, in the capacitance detection type touch panel according to the first aspect, the dielectric layer disposed between the second curved surface of the protective substrate and the substrate has an air with a relative dielectric constant of 1. It is characterized by being.

  A seventh aspect of the present invention is the capacitance detection type touch panel according to any one of the first to fifth aspects, wherein the dielectric layer disposed between the second curved surface of the protective substrate and the substrate is It is a resin or an adhesive material.

According to an eighth aspect of the present invention, in the capacitance detection type touch panel according to the first aspect, the protective substrate has a relative dielectric constant of ε1, and is disposed between the second curved surface of the protective substrate and the substrate on which the electrodes are formed. The dielectric layer relative dielectric constant is ε2, the thickness of the protective substrate in the direction along the normal line of the substrate is D1, and the thickness of the dielectric layer in the direction along the normal line of the substrate is D2. The first curved surface formed on the operation surface of the protective substrate has a thickness of the protective substrate at one end in contact with the substrate as D3, a distance from one end of the first curved surface as X, and the first curved surface. L is a distance from one end to the other end, and the first curved surface is a function of X. D (X) = a · X (XL) + D3 (where a is a positive constant)
When the shape represented by
The thickness D2 (X) of the dielectric layer and the thickness D1 (X) of the protective substrate at a distance X from one end of the first curved surface are D2 (X) = − a · ε2 · X ( XL) / (ε1-ε2)
D1 (X) = D3 + a · ε1 · X (XL) / (ε1−ε2)
The second curved surface of the protective substrate is formed in a curved shape satisfying the above.

  ADVANTAGE OF THE INVENTION According to this invention, the electrostatic capacitance detection type touch panel which provided the uneven shape in the scanning surface can be provided.

(First embodiment)
FIG. 1 is a schematic view showing a configuration of a display device with a touch panel according to the first embodiment of the present invention, and FIG. 2 is a partial cross-sectional view showing a partial cross section of the touch panel.

  As shown in FIG. 1, the display device with a touch panel according to the first embodiment includes a display 8 that displays images, characters, numbers, and the like, a touch panel 7 disposed on the display surface side of the display 8, and the display 8. Display circuit 9 that drives the touch panel 7, touch panel circuit 10 that drives the touch panel 7, and a control circuit 10 that controls the operation of the display circuit 9 and the touch panel 7.

  The display 8 displays an image and also displays a position and a function for input operation when operating the touch panel. In this embodiment, an example is shown in which numbers are input by an input operation on the touch panel.

  As shown in FIG. 2, the touch panel 7 is touched with a conductor such as a finger and corresponds to the touch position displayed on the display 8, and includes a plurality of concave curved surfaces for confirming the touch position with a tactile sensation. The operation surface 1 in which the touch concave portion 1a is formed and the concave portion 1b having a curved surface for adjusting the thickness are formed corresponding to the plurality of touch concave portions 1a on the opposite side of the operation surface 1. A transparent protective substrate 2 having an opposing surface, a transparent touch panel substrate 4 provided with a touch detection electrode 3 disposed opposite to the protective substrate 2 and formed of a transparent conductive film, the protective substrate 2 and the touch panel A dielectric layer 15 having a relative dielectric constant different from that of the protective substrate 2 is disposed between the substrate 4 and the touch substrate 1 so as to correspond to the plurality of touch recesses 1 a of the operation surface 1.

  As shown in FIG. 3, the touch detection electrode 3 of the touch panel substrate 4 includes a plurality of X axis touch detection electrodes 3 a extending in one direction parallel to one side of the touch panel substrate 4 (hereinafter referred to as X axis direction). A plurality of Y-axis touch detection electrodes 3b extending in another direction (hereinafter referred to as the Y-axis direction) orthogonal to the one direction are arranged on the operation surface 1 side of the touch panel 7 and the surface on the opposite side thereof.

  The touch detection electrode pattern is a square repetitive pattern, but is formed in any shape such as a rhombus or a circle.

  The display device with a touch panel of this embodiment displays the touch position corresponding to the numerical value input to the display display and the touch recess 1a, and the operator confirms the displayed touch position with a tactile sense such as a finger. The touch position information is input by touching while touching. A touch panel in which a finger or the like is in contact with the operation surface 1 on the protective substrate includes a touch detection electrode 3 having a finger close to the touch detection electrode 3 in addition to the capacitance of the touch detection electrode itself between the ground and the touch detection electrode 3. A new electrostatic capacitance is added between the protective substrate 2 and the dielectric layer 15 between them, and the electrostatic capacitance between the touch detection electrode 3 and the ground closest to the position where the finger or the like of the operation surface 1 is touched. The capacity changes. A position touched by a finger on the touch panel plane is specified by detecting this change in capacitance by scanning the line-sequentially independently for each X-axis touch detection electrode 3a and each Y-axis touch detection electrode 3b. It is recognized that information such as a numerical value displayed in is input.

  FIG. 3 shows an enlarged cross section of a portion corresponding to the touch concave portion 1a of the protective substrate 2 when a material having a relative dielectric constant smaller than that of the protective substrate is used as the dielectric layer 15 provided between the touch detection electrodes. ing.

  The concave portion 1b formed on the surface opposite to the operation surface 1 of the protective substrate 2 and the dielectric layer 15 are the X-axis touch detection electrode of the touch detection electrode 3 according to the shape of the touch concave portion 1a of the operation surface 1. The shape of the concave portion 1b and the dielectric layer so that the electrostatic capacitance on the surface of each curved portion of the touch concave portion 1a located via the dielectric layer 15 and the protective substrate 2 is substantially equal to 3a. 15 and the relative dielectric constant of the protective substrate 2 are set.

  That is, the recess 1b adjusts the thicknesses of the protective substrate 2 having the first relative dielectric constant and the dielectric layer 15 having the second relative dielectric constant according to the curved surface of the touch recess 1a, A value obtained by synthesizing capacitances generated by the protective substrate 2 having the first relative dielectric constant and the dielectric layer 15 having the second relative dielectric constant at each portion in the touch concave portion 1a is substantially Has a curved surface that is equal to

  The capacitance between the plurality of Y-axis touch detection electrodes 3b formed on the touch panel substrate 4 and the surface of the operation surface 1 of the protective substrate 2 is the same as that of the X-axis touch detection electrode 3a and the operation surface 1. In addition to the protective substrate 2 and the dielectric layer 15 interposed between the surface and the touch panel substrate 4 having a more uniform thickness, the curved surface shape of the recess 1b is not affected. Therefore, the curved surface shape of the concave portion 1b can be determined by paying attention to the capacitance between the X-axis touch detection electrode 3a and the surface of the operation surface 1 of the protective substrate 2.

That is, when the capacitance of the protective substrate 2 is C1, and the capacitance C2 of the dielectric layer, the capacitance C of the protective substrate 2 is C1 and the capacitance C2 having the dielectric layer capacitance C2 interposed between the electrodes. Is a composite when C1 and C2 are connected in series (Equation 1)
1 / C1 + 1 / C2 = 1 / C
It is represented by
Next, the dielectric constant of the protective substrate 2 is ε1, the thickness along the normal line of the touch panel substrate is D1, the thickness along the normal line of the dielectric layer 15 is D2, and the relative dielectric constant. Ε2, a point corresponding to one end of the curved surface of the touch concave portion 1a, that is, the protective substrate 2 and the touch panel substrate 4 are directly in contact with each other without interposing the dielectric layer 15 even though they are located at both ends of the touch concave portion 1a. Is P ₀ and the thickness of the protective substrate 2 in that portion, that is, the thickness of the protective substrate 2 is D3,

General formula of capacitor (Equation 2)
C = εxA / d
(Where C is the capacitance, ε is the relative dielectric constant, A is the electrode area, and d is the distance between the electrodes)
Therefore (Equation 1) is (Equation 3)
D1 / ε1 + D2 / ε2 = D3 / ε1
It becomes.

And P ₀ point corresponding to one end of the curved surface of the touch recess 1a, and the distance from the point P ₀ of an arbitrary point P between the P _L points corresponding to the other end of the curved surface of the touch recesses 1a and X When the thickness of the protective substrate 2 at this point is D1 (X) and the thickness of the dielectric layer 15 is D2 (X), the points P ₀ and P _L corresponding to both ends of the curved surface of the touch recess 1a Then, D2 (0) = D2 (L) = 0, D1 (0) = D1 (L) = D3, and (Equation 3) becomes (Equation 4).
D1 (X) / ε1 + D2 (X) / ε2 = D3 / ε1
It becomes.

If the distance from the surface of the touch detection electrode 3 at an arbitrary point P to the surface of the touch recess 1a formed on the operation surface 1 of the protective substrate 2 is D (X) (Equation 5)
D (X) = D1 (X) + D2 (X)
It becomes.

Here, the concave shape of the touch concave portion 1a formed on the operation surface 1 on the surface of the protective substrate 2 is expressed as a function of X (Equation 6).
D (X) = a · X (XL) + D3
(Where a is a positive constant)
The thickness D2 (X) of the dielectric layer 15 and the thickness D1 (X) of the protective substrate 2 at the arbitrary point P are obtained from (Equation 4) and (Equation 6), respectively. (Equation 7)
D2 (X) = − a · ε2 · X (XL) / (ε1−ε2)
(Equation 8)
D1 (X) = D3 + a · ε1 · X (XL) / (ε1−ε2)
It is represented by

  In this way, when the concave shape of the touch concave portion 1a formed on the operation surface 1 of the protective substrate 2 is changed to a curve represented by (Equation 6), the relative dielectric constant ε1 of the protective substrate 2 and the dielectric layer 15 Depending on the relative dielectric constant ε2, the shape of the concave portion of the protective substrate 2 is curved so as to satisfy (Equation 7) or (Equation 8). The capacitance between the operation surface 1 and the operation surface 1 can be set to a substantially constant value. Therefore, according to this embodiment, it is possible to make the electrostatic capacitance uniform on the operation surface 1 in which the concave touch concave portion 1a of the touch panel is formed.

8, a concave touch recesses 1a, 500 mm distance from the point P ₀ to the point P _L, is shown enlarged in 2mm thickness D3 of the protective substrate 2, the dielectric constant as a protective substrate ε1 A resin substrate of = 2 is used, and the dielectric layer 15 is a space filled with air having a relative dielectric constant ε of 1. A constant a of (Expression 6) representing the concave shape of the touch concave portion 1a formed on the operation surface 1 Is 0.0001, the horizontal axis represents the distance from the point P ₀ to the point P _L , and the vertical axis represents the height from the X-axis touch detection electrode 3a. In FIG. 8, the cross-sectional shape of the touch recess 1 a formed on the operation surface 1 of the protective substrate 2 is represented by a curve 16, and the cross-sectional shape of the dielectric layer 15 is represented by a curve 17.

  That is, the protective substrate 2 has a touch concave portion 1a having a shape indicated by a curve 16 on the operation surface 1 and a shape represented by a curve 17 on a surface opposite to the operation surface 1 of the protection substrate 2 correspondingly. By forming a recess 1b and filling air between the recess 1b and the X-axis touch detection electrode 3a, the capacitance on the operation surface 1 where the concave touch recess 1a of the touch panel is formed is made uniform. can do.

(Second Embodiment)
In the second embodiment of the present invention, as shown in FIG. 5, a touch convex portion 1 c composed of a convex curved surface for confirming the position by tactile sensation is formed on the operation surface 1 of the touch panel, and the touch detection electrode 3X is formed. A display device with a touch panel using a material having a relative dielectric constant larger than that of a protective substrate as a dielectric layer provided between the shaft touch detection electrodes 3a is shown.

  FIG. 6 shows an enlarged cross section of a portion corresponding to the touch convex portion 1c of the protective substrate 2 when a material having a relative dielectric constant larger than that of the protective substrate is used as the dielectric layer provided between the touch panel electrodes. . The concave portion 1d formed on the surface opposite to the operation surface 1 of the protective substrate 2 and the dielectric layer 15a are configured to detect the X-axis touch of the touch detection electrode 3 according to the shape of the touch convex portion 1c of the operation surface 1. The shape of the concave portion 1d and the dielectric so that the electrostatic capacitance on the surface of each curved portion of the touch convex portion 1c located through the dielectric layer 15 and the protective substrate 2 with respect to the electrode 3a is substantially equal. The relative dielectric constant values of the body layer 15a and the protective substrate 2 are set.

  That is, the concave portion 1d is formed by touching the thickness of the protective substrate 2 having the first relative dielectric constant and the dielectric layer 15a having the second relative dielectric constant larger than the first relative dielectric constant. It adjusts according to the curved surface of the convex part 1c, and adds the protective substrate 2 having the first relative dielectric constant and the dielectric layer 15a having the second relative dielectric constant at each part of the touch convex part 1c. The dielectric constant has a curved surface that is substantially equal.

  Also in this embodiment, when the convex shape of the touch convex portion 1c formed on the operation surface 1 of the protective substrate 2 is changed to the curve shown in (Equation 6), as in the first embodiment described above, the protective substrate In accordance with the relative dielectric constant ε1 of 2 and the relative dielectric constant ε2 of the dielectric layer 15a, the shape of the concave portion of the protective substrate 2 is formed in a curve so as to satisfy (Equation 7) or (Equation 8). Thus, the capacitance between the touch detection electrode 3 and the operation surface 1 at an arbitrary point P can be set to a substantially constant value. Therefore, according to this embodiment, it is possible to make the electrostatic capacitance uniform on the operation surface 1 in which the convex touch convex portion 1c is formed on the touch panel.

9, the convex shape of the touch protrusions 1c, shows the distance from the point P ₀ to the point P _L 500 mm, the thickness D3 of the protective substrate 2 in an enlarged view of 2 mm, the dielectric constant as a protective substrate Using a resin substrate with ε1 = 2, the dielectric layer 15a is filled with a substance having a relative dielectric constant ε of 2.6, and represents the convex shape of the touch convex portion 1c formed on the operation surface 1 (Expression 6) the a and 0.0003, the distance from the point P ₀ on the horizontal axis to the point P _L, taking the height from the X-axis touch detection electrode 3a on the vertical axis represents its shape. In FIG. 9, the cross-sectional shape of the touch protrusion 1 c formed on the operation surface 1 of the protective substrate 2 is represented by a curve 18, and the cross-sectional shape of the dielectric layer 15 is represented by a curve 19.

  That is, the protective substrate 2 is represented by a curved line 19 on the surface opposite to the operational surface 1 of the protective substrate 2 in correspondence with the curved touch convex portion 1 c represented by the curved line 18. A curved concave portion 1d is formed, and a dielectric layer 15a is filled between the concave portion 1d and the X-axis touch detection electrode 3a, whereby a touch-shaped convex convex portion 1c of the touch panel is formed on the operation surface 1. Can be made uniform in capacitance.

  Examples of the dielectric layer having a relative dielectric constant larger than that of the protective substrate include an acrylic resin having a relative dielectric constant of 2.7 to 4.5, a polycarbonate resin having a relative dielectric constant of 2.9 to 3.0, or methacrylic resin. Resin, styrene resin, or the like can be used.

(Third embodiment)
The third embodiment is a display device with a touch panel in which a plurality of convex touch projections 1c and a plurality of concave touch recesses 1a for confirming the position by touch are formed on the operation surface 1 of the touch panel. .

  As shown in FIG. 7, in the display device with a touch panel of this embodiment, a touch convex portion 1 c and a touch concave portion 1 a are formed on the operation surface 1, and concave portions 1 d and 1 b are formed on the surface opposite to the operation surface 1. The protective substrate 2 and the dielectric layers 15a and 15 are formed. The protective substrate 2 and the dielectric layers 15a and 15 are formed of a dielectric with respect to the X-axis touch detection electrode 3a of the touch detection electrode 3 according to the shapes of the touch convex portion 1c and the touch concave portion 1a of the operation surface 1, respectively. The shape of the recesses 1d and 1b so that the electrostatic capacitance on the surface of each curved surface of the touch protrusion 1c and the touch recess 1a located via the layers 15 and 15a and the protective substrate 2 is substantially equal. Values of relative dielectric constants of the dielectric layers 15a and 15 and the protective substrate 2 are set.

  That is, the recesses 1b and 1d include the protective substrate 2 having a first relative dielectric constant, the second dielectric layer 15 having a relative dielectric constant smaller than the first relative dielectric constant, The thickness of the dielectric layer 15a having a third dielectric constant larger than the relative dielectric constant of the touch concave portion 1a and the touch convex portion 1c is adjusted according to the curved surfaces of the touch concave portion 1a and the touch convex portion 1c. The protective substrate 2 having the first relative dielectric constant, the dielectric layer 15 having the second relative dielectric constant, the protective substrate 2 having the first relative dielectric constant, and the third The values obtained by synthesizing the capacitances generated by the dielectric layer 15a having a relative dielectric constant have curved surfaces that are substantially equal to each other. The curved surfaces of the recesses 1b and 1d can be determined in the same manner as the first embodiment and the twenty-first embodiment, respectively, according to the touch recess 1a and the touch protrusion 1c.

  According to the third embodiment, it is possible to make the electrostatic capacitance uniform on the operation surface 1 in which the concave touch concave portion 1a and the convex touch convex portion 1c are formed on the touch panel.

  In the first to third embodiments described above, an example is provided in which a plurality of touch positions are provided on one touch panel, and touch concave portions 1a and touch convex portions 1c for confirming the plurality of operation positions with a tactile sensation are provided. Although shown, the present invention is not limited to this. For example, the entire operation surface 1 of one touch panel is formed in one convex shape or concave shape, and is made to correspond to this one convex shape or concave shape. Thus, one recess 1b or 1d may be formed. In this case, a touch panel having a curved surface as a whole is obtained.

Further, the convex shape or the concave shape formed on the operation surface 1 of the touch panel may be an arbitrary shape on the operation surface 1, for example, a shape representing a figure.
Furthermore, in any embodiment, the display panel 7 is not particularly limited, and any of CRT, liquid crystal display, organic EL, PDP, electronic paper display, and the like can be used.

1 is a configuration diagram of a display device of the present invention. Sectional drawing of the display apparatus with a touchscreen of the 1st Embodiment of this invention. Detailed drawing of the touch-panel electrode which can be used for embodiment of this invention. Sectional drawing of the touchscreen of the 1st Embodiment of this invention. Sectional drawing of the display apparatus with a touchscreen of the 2nd Embodiment of this invention. Sectional drawing of the touchscreen of the 2nd Embodiment of this invention. Sectional drawing of the display apparatus with a touchscreen of the 3rd Embodiment of this invention. The graph which shows the relationship of the thickness of the vertical direction of the touchscreen of the 1st Embodiment of this invention. The graph which shows the relationship of the thickness of the vertical direction of the touchscreen of the 2nd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Operation surface 2 ... Protective substrate 3 ... Touch detection electrode 4 ... Touch panel substrate 7 ... Touch panel 8 ... Display display 9 ... Display circuit 10 ... Touch panel circuit 11- ..Control circuit 14 ... Touch panel electrode substrate 15 ... Dielectric layers 16, 18 ... Vertical thickness from touch panel electrode to operation surface 17 ... Dielectric layer (air layer) thickness 19: Dielectric layer thickness

Claims (8)

An operating surface on which at least one first curved surface is formed, and a thickness that defines the thickness of the portion on the opposite side of the operating surface corresponding to the first curved surface, on which the first curved surface is formed. A transparent protective substrate having an opposing surface provided with two curved surfaces;
A transparent substrate disposed opposite to the protective substrate and provided with an electrode made of a transparent conductive film;
A dielectric layer disposed between the second curved surface of the protective substrate and the substrate in correspondence with the first curved surface of the operation surface, and having a relative dielectric constant different from that of the protective substrate;
An electrostatic capacitance detection type touch panel comprising:   The second curved surface and the dielectric layer formed on the opposing surface of the protective substrate are on the surface of each part of the first curved surface located via the dielectric layer and the protective substrate with respect to the electrode on the substrate. According to the shape of the first curved surface, the shape of the second curved surface and the dielectric constant of the dielectric layer and the protective plate are set so that the capacitances are substantially equal. 2. The capacitance detection type touch panel according to claim 1, wherein   The second curved surface formed on the opposing surface of the protective substrate includes a protective substrate having a first relative dielectric constant and a dielectric layer having a second relative dielectric constant at each portion of the first curved surface of the operation surface. And a concave curved surface having a shape in which the thicknesses of the protective substrate and the dielectric layer are changed according to the first curved surface of the operation surface so that the combined values of the capacitances respectively generated by The capacitance detection type touch panel according to claim 1, wherein the capacitance detection type touch panel is formed. The first curved surface formed on the operation surface of the protective substrate is a convex portion protruding from the operation surface,
The dielectric layer disposed between the second curved surface of the protective substrate and the substrate is made of a dielectric material having a relative dielectric constant larger than that of the protective substrate. The capacitance detection type touch panel as described. The second curved surface formed on the operation surface of the protective substrate is a concave curved surface formed in a shape recessed from the operation surface,
The dielectric layer disposed between the second curved surface of the protective substrate and the substrate is made of a dielectric material having a relative dielectric constant smaller than that of the protective substrate. The capacitance detection type touch panel as described.   The capacitance detection type touch panel according to claim 5, wherein the dielectric layer disposed between the second curved surface of the protective substrate and the substrate is air having a relative dielectric constant of 1.   The capacitance detection type touch panel according to claim 1, wherein the dielectric layer disposed between the second curved surface of the protective substrate and the substrate is a resin or an adhesive material. . The relative dielectric constant of the protective substrate is ε1, the relative dielectric constant of the dielectric layer disposed between the second curved surface of the protective substrate and the substrate on which the electrodes are formed is ε2, and the direction along the normal line of the substrate The thickness of the protective substrate is D1, the thickness of the dielectric layer in the direction along the normal of the substrate is D2, and the first curved surface formed on the operation surface of the protective substrate is in contact with the substrate. The thickness of the protective substrate at the end is D3, the distance from one end of the first curved surface is X, the distance from one end of the first curved surface to the other end is L, and the first curved surface is X function D (X) = a · X (XL) + D3 (where a is a positive constant)
When the shape is
The thickness D2 (X) of the dielectric layer and the thickness D1 (X) of the protective substrate at a distance X from one end of the first curved surface are D2 (X) = − a · ε2 · X ( XL) / (ε1-ε2)
D1 (X) = D3 + a · ε1 · X (XL) / (ε1−ε2)
The capacitance detection type touch panel according to claim 1, wherein the second curved surface of the protective substrate is formed in a curved shape satisfying the above.

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