Capacitive sensing input device

Abstract

The present invention provides a capacitive sensing input device that can suppress brightness variations on the luminescent operating surface. [Solution] The capacitance detection input device 10 comprises a resin layer 31 that is light-transmitting and whose surface is a design surface 31a, an electrostatic sensor sheet 22 placed on top of the back surface of the resin layer 31, and a light source (light-emitting element 20a) that irradiates the resin layer 31 and the electrostatic sensor sheet 22 with light. The resin layer 31 has an uneven light transmittance, and the electrostatic sensor sheet 22 is configured with an uneven aperture ratio for light to pass through in order to suppress brightness variations of light transmitted through the resin layer 31.

Description

Technical Field

[0001] The present disclosure relates to a capacitance detection type input device.

Background Art

[0002] As a conventional technique, an electrode sheet for a capacitive touch panel is known.

[0003] For example, Patent Document 1 discloses an electrode sheet for a capacitive touch panel having a transparent substrate, a first conductive portion formed on one main surface of the substrate, and a second conductive portion formed on the other main surface of the substrate.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] For example, in a steering switch of a vehicle or the like, concavities and convexities are formed on the operation surface in consideration of design. In order to illuminate the operation surface, a light source may be arranged inside the steering switch. In this case, it is considered that the operation surface can be made to emit light uniformly by adjusting the thickness of the resin layer constituting the operation surface. However, when applying the electrode sheet for a capacitive touch panel of Patent Document 1 to a steering switch, in a configuration where this electrode sheet for a capacitive touch panel is attached to the resin layer, it becomes difficult to adjust the wall thickness of the resin layer, and there is a problem that it becomes difficult to suppress the luminance unevenness of the light-emitting operation surface.

[0006] Therefore, an object of the present disclosure is to provide a capacitance detection type input device capable of suppressing the luminance unevenness of a light-emitting operation surface.

Means for Solving the Problems

[0007] A capacitance detection input device according to one aspect of the present disclosure comprises a resin layer having light transmittance and a surface having a design surface, an electrostatic sensor sheet placed on top of the back surface of the resin layer, and a light source that irradiates the resin layer and the electrostatic sensor sheet with light, wherein the light transmittance of the resin layer is non-uniform, and the electrostatic sensor sheet is configured to have a non-uniform aperture ratio for light to pass through in order to suppress brightness variations of light transmitted through the resin layer. [Effects of the Invention]

[0008] According to the capacitance detection input device of this disclosure, it is possible to suppress brightness variations on the light-emitting operating surface. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1 is a schematic diagram showing a capacitive sensing input device mounted on a vehicle. [Figure 2] Figure 2 is a block diagram of a capacitance detection input device. [Figure 3] Figure 3 is a cross-sectional view showing a capacitance detection input device. [Figure 4] Figure 4 shows the brightness variations of light that have passed through the resin layer and emerged from the design surface. [Figure 5] Figure 5 shows the dot pattern of the light-shielding area in the electrostatic sensor sheet. [Figure 6] Figure 6 shows the mesh pattern of the light-shielding portion in the electrostatic sensor sheet. [Modes for carrying out the invention]

[0010] The embodiments will be described in detail below with reference to the drawings.

[0011] The embodiments described below are all comprehensive or specific examples. The numerical values, shapes, materials, components, arrangement positions of components, and connection configurations shown in the following embodiments are examples only and are not intended to limit this disclosure. Furthermore, any components in the following embodiments that are not described in an independent claim will be described as optional components.

[0012] Furthermore, each figure is a schematic diagram and not necessarily a strictly accurate representation. Also, the same component is denoted by the same reference numeral in each figure.

[0013] Furthermore, in the following embodiments, expressions such as "approximately parallel" and "rectangular" are used. For example, "approximately parallel" and "rectangular" mean not only that they are perfectly parallel and perfectly rectangular, but also that they are substantially parallel and substantially rectangular, that is, that they include an error of, for example, a few percent. Also, "approximately parallel" and "rectangular" means parallel and rectangular to the extent that the effects of this disclosure can be achieved. The same applies to other expressions using "approximately" and "shaped".

[0014] (Embodiment) <Structure> First, the configuration of the capacitance detection input device 10 will be explained using Figures 1 to 6.

[0015] Figure 1 is a schematic diagram showing a capacitance detection input device 10 mounted on a vehicle 1. Figure 2 is a block diagram of the capacitance detection input device 10. Figure 3 is a cross-sectional view showing the capacitance detection input device 10. Figure 4 shows the brightness variations of light emitted from the design surface 31a after passing through the resin layer 31. Figure 5 shows the dot pattern of the light-shielding portion 22b in the electrostatic sensor sheet 22. Figure 6 shows the mesh pattern of the light-shielding portion 22b in the electrostatic sensor sheet 22.

[0016] As shown in FIG. 1, the capacitance detection type input device 10 is arranged with its operation surface exposed on a spoke, center console, door, instrument panel, roof, etc. that are connected to the steering shaft of the vehicle 1. Thereby, the capacitance detection type input device 10 can receive an operation input to the operation surface from the user. In FIG. 1, the case where the capacitance detection type input device 10 is arranged on the spoke connected to the steering shaft of the vehicle 1 is illustrated. Note that the capacitance detection type input device 10 is not limited to, for example, the present embodiment, and may be arranged at other locations in the vehicle compartment.

[0017] The capacitance detection type input device 10 outputs a signal based on an operation input for controlling in-vehicle devices to the in-vehicle devices by receiving an operation input from the user. Thereby, the in-vehicle devices can operate according to the operation input. The in-vehicle devices are, for example, a car navigation system equipped with a display device or the like, an audio device for playing an optical disk, an in-vehicle air conditioner, in-vehicle lighting, or a video playback device. Thus, the user can operate the in-vehicle devices mounted on the vehicle 1 by performing an operation input on the capacitance detection type input device 10.

[0018] Next, the specific configuration of the capacitance detection type input device 10 will be described.

[0019] As shown in FIGS. 1 to 3, the capacitance detection type input device 10 includes a light emitting module 20, a lighting control circuit 21, a resin layer 31, an electrostatic sensor sheet 22, and a control unit 23.

[0020] The light emitting module 20 is arranged to face the electrostatic sensor sheet 22.

[0021] The light emitting module 20 has one or more light emitting elements 20a that emit light and a substrate 20b on which the one or more light emitting elements 20a are arranged. The light emitting element 20a is an example of a light source. Also, the light emitting module 20 may be an example of a light source.

[0022] One or more light-emitting elements 20a are arranged to face the electrostatic sensor sheet 22. One or more light-emitting elements 20a can emit light toward the resin layer 31 and the electrostatic sensor sheet 22.

[0023] Each of the one or more light-emitting elements 20a emits light (e.g., white light) in response to a current supplied from the lighting control circuit 21, and is, for example, an LED (Light Emitting Diode). Each of the one or more light-emitting elements 20a is, for example, a blue light-emitting element that emits blue light, a green light-emitting element that emits green light, and / or a red light-emitting element that emits red light.

[0024] One or more light-emitting elements 20a are mounted on a substrate 20b. The substrate 20b is a rigid substrate, but may also be a flexible substrate. The substrate 20b is provided with patterned wiring for electrically connecting each of the one or more light-emitting elements 20a to the lighting control circuit 21.

[0025] The lighting control circuit 21 can individually control the on / off state of each of the one or more light-emitting elements 20a by supplying DC power to each of them. The lighting control circuit 21 may also have a dimming function and a color adjustment function. The lighting control circuit 21 can change the light emission intensity of each of the one or more light-emitting elements 20a according to the amount of current supplied to each of them. The one or more light-emitting elements 20a may include multiple types of light-emitting elements 20a that emit white light with different color temperatures. The lighting control circuit 21 can emit white light of a desired color temperature by adjusting the light emission intensity of each of the one or more light-emitting elements 20a. The lighting control circuit 21 may be mounted on the same substrate 20b as the one or more light-emitting elements 20a, or it may be mounted on a different substrate.

[0026] As shown in Figure 3, the resin layer 31 is light-transmitting and is formed from, for example, an acrylic plate, glass, or the like. In this embodiment, the resin layer 31 has a rectangular shape when viewed from above. However, the shape of the resin layer 31 when viewed from above is not limited to a rectangle; it may be a polygonal shape other than a rectangle, or it may be circular.

[0027] The resin layer 31 has a design surface 31a and an opposing surface 31b.

[0028] The design surface 31a is the surface (operation surface) of the resin layer 31 that can directly receive operation input from the user. The design surface 31a has a raised pattern or symbol formed on it to indicate operation input. The opposing surface 31b is the back surface of the resin layer 31 opposite to the design surface 31a. The opposing surface 31b is positioned to face the electrostatic sensor sheet 22.

[0029] As described above, the resin layer 31 has uneven thickness due to the formation of a pattern or symbol on the design surface 31a. Therefore, the light transmittance of the resin layer 31 is non-uniform.

[0030] Specifically, the resin layer 31 has a thin portion 131 where the thickness is reduced, and a thick portion 132 where the thickness is greater than that of the thin portion 131. The resin layer 31 has the characteristic that the light transmittance is high in the thin portion 131 and low in the thick portion 132.

[0031] In other words, as the thickness of the resin layer 31 increases, the brightness of the transmitted light tends to decrease. As shown in Figures 3 and 4, the brightness of the transmitted light through the resin layer 31 is brighter in the thin portion 131 and darker in the thick portion 132 than in the thin portion 131.

[0032] The electrostatic sensor sheet 22 is positioned approximately parallel to the resin layer 31 and is placed on top of the opposing surface 31b of the resin layer 31. The electrostatic sensor sheet 22 is attached to the opposing surface 31b of the resin layer 31, for example, by a translucent adhesive.

[0033] The electrostatic sensor sheet 22 is configured with an uneven aperture ratio for light to pass through, in order to suppress brightness variations of light transmitted through the resin layer 31. In the electrostatic sensor sheet 22 of this embodiment, the higher the aperture ratio of the electrostatic sensor sheet 22, the greater the brightness of the light transmitted through the electrostatic sensor sheet 22, i.e., the brighter it becomes.

[0034] Specifically, the electrostatic sensor sheet 22 is configured such that the aperture ratio of the portion of the electrostatic sensor sheet 22 corresponding to the portion with higher light transmittance in the resin layer 31 is lower. In other words, the aperture ratio of the portion of the electrostatic sensor sheet 22 corresponding to the portion with thinner resin layer 31 is lower.

[0035] More specifically, the electrostatic sensor sheet 22 has a light-transmitting sheet 22a, a light-shielding portion 22b that blocks light, and an electrode 22c.

[0036] The transparent sheet 22a is formed from a light-transmitting resin material such as polyethylene terephthalate.

[0037] The light-shielding portion 22b is made of a metallic material such as silver. However, the light-shielding portion 22b may be made of any material that has the function of absorbing or reflecting light.

[0038] The light-shielding portion 22b may be a dot pattern arranged on the transparent sheet 22a, as shown in Figure 5, or a mesh pattern, as shown in Figure 6. The dot pattern is circular, but may also be polygonal. The mesh pattern has a rectangular mesh shape, but may also have a mesh shape of other polygons or circular shapes. The light-shielding portion 22b is formed, for example, by printing on the transparent sheet 22a.

[0039] Because the light transmittance is non-uniform in the resin layer 31, the electrostatic sensor sheet 22 is configured such that areas with higher light transmittance in the resin layer 31 correspond to areas with higher density per unit area of ​​the light-shielding portion 22b. Areas with higher density per unit area of ​​the light-shielding portion 22b have a lower aperture ratio. In this way, the density per unit area of ​​the light-shielding portion 22b differs in the electrostatic sensor sheet 22 in order to suppress brightness variations of light transmitted through the resin layer 31.

[0040] For example, the electrostatic sensor sheet 22 has a portion 141 indicated by a dashed line that is configured to have a first aperture ratio, and a portion 142 indicated by a double dashed line that is configured to have a second aperture ratio that is higher than the first aperture ratio. Note that portions 141 and 142 shown in Figures 5 and 6 are merely examples and are not limited to the locations shown in Figures 5 and 6. The portion of the electrostatic sensor sheet 22 facing the thin portion 131 of the resin layer 31 is configured to have a first aperture ratio with a low aperture ratio, and the portion of the electrostatic sensor sheet 22 facing the thick portion 132 of the resin layer 31 is configured to have a second aperture ratio that is higher than the first aperture ratio.

[0041] In this embodiment, since the capacitance detection input device 10 is equipped with the resin layer 31 and electrostatic sensor sheet 22 as described above, the light emitted by the light-emitting element 20a is emitted more uniformly when it passes through the resin layer 31 and electrostatic sensor sheet 22.

[0042] The electrode 22c may be placed on the transparent sheet 22a and spaced apart from the light-shielding portion 22b. The electrode 22c does not have to be electrically connected to the light-shielding portion 22b. However, if the light-shielding portion 22b is a mesh pattern, the electrode 22c may be electrically connected to the light-shielding portion 22b.

[0043] The electrode 22c can detect operational input to the design surface 31a of the resin layer 31. The electrode 22c is not electrically connected to the light-shielding portion 22b. The electrode 22c outputs a signal to the control unit 23 for detecting the position of the operating object that has come into contact with the design surface 31a.

[0044] The control unit 23 can detect the position on the design surface 31a that has been operated on, based on the signal detected by the electrode 22c of the electrostatic sensor sheet 22. The control unit 23 outputs a signal based on the detected position to the in-vehicle equipment.

[0045] <Effects and Effects> Next, the effects and advantages of the capacitance detection input device 10 in this embodiment will be described.

[0046] As described above, the capacitance detection input device 10 shown in Technology 1 of this embodiment comprises a resin layer 31 that is light-transmitting and whose surface is a design surface 31a, an electrostatic sensor sheet 22 placed on top of the back surface of the resin layer 31, and a light source (light-emitting element 20a) that irradiates the resin layer 31 and the electrostatic sensor sheet 22 with light. The resin layer 31 has an uneven light transmittance, and the electrostatic sensor sheet 22 is configured with an uneven aperture ratio for light to pass through in order to suppress brightness variations of light transmitted through the resin layer 31.

[0047] According to this, it is expected that the light emitted by the light-emitting element 20a that has passed through the electrostatic sensor sheet 22 and the resin layer 31 will be made uniform.

[0048] Therefore, the capacitance detection input device 10 can suppress brightness variations on the light-emitting operating surface.

[0049] Furthermore, as described above, the capacitance detection input device 10 shown in Technical 2 of this embodiment is the same capacitance detection input device 10 shown in Technical 1. In this case, the electrostatic sensor sheet 22 is configured such that the aperture ratio of the portion of the electrostatic sensor sheet 22 corresponding to the portion with higher light transmittance in the resin layer 31 becomes lower.

[0050] According to this, the resin layer 31 and the electrostatic sensor sheet 22 can be arranged such that areas of the resin layer 31 with low light transmittance correspond to areas of the electrostatic sensor sheet 22 with high aperture ratio, and areas of the resin layer 31 with high light transmittance correspond to areas of the electrostatic sensor sheet 22 with low aperture ratio. Therefore, it is possible to suppress brightness variations on the light-emitting operating surface.

[0051] Furthermore, as described above, the capacitance detection input device 10 shown in Technology 3 of this embodiment is the capacitance detection input device 10 shown in Technology 1 or 2. In this case, the electrostatic sensor sheet 22 has a light-transmitting sheet 22a, a light-shielding portion 22b that blocks light, and an electrode 22c arranged on the light-transmitting sheet 22a and spaced apart from the light-shielding portion 22b. The light-shielding portion 22b is a dot pattern arranged on the light-transmitting sheet 22a, and the portion of the electrostatic sensor sheet 22 corresponding to the portion with high light transmittance in the resin layer 31 is arranged to have a lower aperture ratio.

[0052] According to this, the light-shielding portion 22b can be positioned such that areas with low light transmittance in the resin layer 31 correspond to areas with high aperture ratio in the electrostatic sensor sheet 22, and areas with high light transmittance in the resin layer 31 correspond to areas with low aperture ratio in the electrostatic sensor sheet 22. Therefore, it is possible to suppress brightness variations on the light-emitting operating surface.

[0053] Furthermore, as described above, the capacitance detection input device 10 shown in Technology 4 of this embodiment is the capacitance detection input device 10 shown in Technology 1 or 2. In this case, the electrostatic sensor sheet 22 has a light-transmitting sheet 22a and a light-shielding portion 22b that blocks light, and the light-shielding portion 22b is a mesh pattern arranged on the light-transmitting sheet 22a, and is arranged such that the aperture ratio of the portion of the electrostatic sensor sheet 22 corresponding to the portion with higher light transmittance in the resin layer 31 becomes lower.

[0054] According to this, the light-shielding portion 22b can be positioned such that areas with low light transmittance in the resin layer 31 correspond to areas with high aperture ratio in the electrostatic sensor sheet 22, and areas with high light transmittance in the resin layer 31 correspond to areas with low aperture ratio in the electrostatic sensor sheet 22. Therefore, it is possible to suppress brightness variations on the light-emitting operating surface.

[0055] Furthermore, as described above, the capacitance detection input device 10 shown in Technology 5 of this embodiment is the capacitance detection input device 10 shown in any one of Technologies 1 to 4. In this case, the resin layer 31 has different thicknesses, and the thinner the resin layer 31, the lower the opening ratio of the electrostatic sensor sheet 22 corresponding to that portion.

[0056] According to this, the resin layer 31 and the electrostatic sensor sheet 22 can be arranged such that the aperture ratio of the electrostatic sensor sheet 22 is low in areas of the resin layer 31 where the thickness of the resin layer 31 is thin and the light transmittance is low, and the aperture ratio of the electrostatic sensor sheet 22 is high in areas of the resin layer 31 where the thickness of the resin layer 31 is thick. As a result, brightness variations on the light-emitting operating surface can be suppressed.

[0057] (Other variations, etc.) Although the present disclosure has been described above based on embodiments, the present disclosure is not limited to the embodiments described above.

[0058] For example, the control unit and other components included in the capacitance detection input device according to the above embodiment are typically implemented as an LSI (Large-Scale Integrated Circuit). These may be individually integrated into a single chip, or some or all of them may be integrated into a single chip.

[0059] Furthermore, integrated circuit implementation is not limited to LSIs; it may also be achieved using dedicated circuits or general-purpose processors. Field-Programmable Gate Arrays (FPGAs), which can be programmed after LSI manufacturing, or reconfigurable processors, which allow for the reconfiguration of the connections and settings of circuit cells within the LSI, may also be used.

[0060] In the above embodiment, each component may be implemented by dedicated hardware or by executing a software program suitable for each component. Each component may also be implemented by a program execution unit such as a CPU or processor reading and executing a software program recorded on a recording medium such as a hard disk or semiconductor memory.

[0061] Furthermore, the division of functional blocks in the block diagram is just one example; multiple functional blocks can be implemented as a single functional block, a single functional block can be divided into multiple parts, or some functions can be moved to other functional blocks. In addition, the functions of multiple functional blocks with similar functions can be processed in parallel or time-sharing by a single piece of hardware or software.

[0062] Furthermore, this disclosure also includes forms obtained by applying various modifications to the embodiments that a person skilled in the art could conceive, and forms realized by arbitrarily combining the components and functions of the embodiments without departing from the spirit of this disclosure. [Industrial applicability]

[0063] The capacitance detection input device of this disclosure can be used, for example, as an input device mounted in a vehicle. [Explanation of Symbols]

[0064] 10 Capacitive sensing input device 20a Light-emitting element (light source) 22 Electrostatic Sensor Sheet 22a Transparent Sheet 22b Light shielding part 22c electrode 31 Resin layer 31a Design surface (surface) 31b Opposite side (back side)

Claims

1. A resin layer that has light transmittance and whose surface is a decorative surface, An electrostatic sensor sheet is placed on top of the back surface of the aforementioned resin layer, The system comprises a light source that irradiates the resin layer and the electrostatic sensor sheet with light, In the aforementioned resin layer, the light transmittance is non-uniform. The electrostatic sensor sheet is configured with an uneven aperture ratio for light to pass through, in order to suppress brightness variations of light transmitted through the resin layer. Capacitive sensing input device.

2. The electrostatic sensor sheet is configured such that the aperture ratio of the portion of the electrostatic sensor sheet corresponding to a portion with high light transmittance in the resin layer becomes lower. Capacitance detection input device according to claim 1.

3. The electrostatic sensor sheet comprises a light-transmitting sheet, a light-shielding portion that blocks light, and electrodes arranged on the light-transmitting sheet and spaced apart from the light-shielding portion. The light-shielding portion is, This is a dot pattern arranged on the aforementioned transparent sheet. The resin layer is arranged such that the aperture ratio of the portion of the electrostatic sensor sheet corresponding to a portion with high light transmittance becomes lower in that portion. Capacitive detection input device according to claim 1 or 2.

4. The electrostatic sensor sheet has a light-transmitting sheet and a light-shielding portion that blocks light. The light-shielding portion is, This is a mesh pattern arranged on the transparent sheet. The resin layer is arranged such that the aperture ratio of the portion of the electrostatic sensor sheet corresponding to a portion with high light transmittance becomes lower in that portion. Capacitive detection input device according to claim 1 or 2.

5. The aforementioned resin layers have different thicknesses. The thinner the resin layer, the lower the aperture ratio of the portion of the electrostatic sensor sheet corresponding to that portion. Capacitive detection input device according to claim 1 or 2.

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