JP2013178899A - Touch panel, and terminal device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a proximity sensor from receive light reflected on the surface of a screen glass, the surface of a protective sheet, and the boundary surface of the screen glass and a protective sheet.SOLUTION: A touch panel includes a screen glass 101, a substrate 104 whose rear surface is fixed to the screen glass 101 and which has a pair of through holes penetrating the substrate 104 so as to connect a front and a rear surfaces thereof, and a proximity sensor 100 including a light-emitting part 106 attached to the front surface of the substrate 104 and emitting infrared ray toward the screen glass 101 side through one of the through holes, and a light-receiving part 107 receiving infrared ray from the screen glass 101 side through the other of the through holes.

Description

  The present invention relates to a touch panel and a terminal device.

  A portable information terminal such as a smartphone has a function to disable the touch panel function to prevent erroneous operation and a function to turn off the backlight for power saving when the user's face approaches the terminal device during a call. ing. In order to realize such a function, the portable information terminal is provided with a proximity sensor that detects the face of the user approaching the terminal using infrared rays. Such a proximity sensor is often arranged on the screen glass surface under the restriction of the space inside the casing of the portable information terminal.

  As a known example in this field, for example, Patent Document 1 describes an infrared switch device that operates as a setting switch even when there is a disturbance due to sunlight or the like. More specifically, the infrared switch device described in Patent Document 1 includes a photo reflector having a light emitting element and a light receiving element, and a light shielding plate provided between the photo reflector and the glass. Whether or not a reflector is placed at a predetermined position is determined based on the amount of reflected light.

  Patent Document 2 describes an infrared proximity sensor that reduces crosstalk of infrared signals. More specifically, the infrared proximity sensor described in Patent Document 2 attenuates unnecessary infrared rays that may be incident on the infrared receiver die by the partitioning divider of the housing and the infrared absorbing material of the upper shield. Or absorb.

Japanese Patent No. 3758181 JP 2011-113975 A

  By the way, a portable information terminal may be used in a state where a protective sheet is stuck on the surface of a touch panel. In that case, the protective sheet may also cover a window that transmits infrared rays of the proximity sensor provided in the housing of the portable information terminal. In such a state, the proximity sensor may receive reflected light generated on the surface of the protective sheet or the interface of the screen glass, and there is a risk of erroneous detection. In the following description, the cause of such erroneous detection will be described in detail.

  FIGS. 7-9 shows an example of the structure of the vicinity of the proximity sensor 300 in a general touch panel. A detection object X is shown outside the screen glass 301. The detection target X is, for example, a user's face. When the detection object X approaches the screen glass 301, the proximity sensor 300 receives the infrared light irradiated from the light emitting unit 306 and reflected by the detection object X by the light receiving unit 307, thereby detecting the detection object X. Is detected.

  Here, let L be the distance between the screen glass 301 and the proximity sensor 300. In the proximity sensor 300 in a general touch panel, the opposite surface of the light emitting unit 306 and the light receiving unit 307 is fixed to the substrate 304. Therefore, the substrate 304 is provided in consideration of the component height tolerance of each mounted component including the proximity sensor 300.

  That is, when the component height tolerance of each mounted component including the proximity sensor 300 is very small, the proximity sensor 300 can be provided so that the distance L becomes small as shown in FIG. In that case, the light receiving unit 307 of the proximity sensor 300 receives the infrared ray 608 reflected by the detection target X, but does not receive the reflected light 609 on the surface of the screen glass 301.

  However, it is very difficult to reduce the distance L in the touch panel having such a configuration. That is, in practice, the distance L is increased as shown in FIG. Therefore, the light receiving unit 307 of the proximity sensor 300 receives the infrared light 708 reflected by the detection target X and also receives the infrared light 709 and 710 reflected by the surface of the screen glass 301.

  In the touch panel shown in FIG. 9, a protective sheet 813 is attached to the screen glass 301. In the touch panel to which the protective sheet 813 is attached in this way, light is reflected also at the interface between the screen glass 301 and the protective sheet 813. As a result, the light receiving unit 307 of the proximity sensor 300 may receive more reflected light. Here, there are various types of the protective sheet 813, and the reflectance and refractive index are different depending on the type. However, when designing a touch panel, it is difficult to design the touch panel so as to correspond to various protective sheets 813.

  The objective of this invention is providing the touchscreen and terminal device which solve the subject mentioned above.

In order to solve the above-mentioned problems, a touch panel according to the present invention is attached to a screen glass, a substrate having a back surface fixed to the screen glass, and a pair of through holes penetrating from the front surface to the back surface, and the surface of the substrate. And a proximity sensor having a light emitting unit that emits infrared light to the screen glass side through one through hole and a light receiving unit that receives infrared light from the screen glass side through the other through hole.

  The terminal device according to the present invention includes the touch panel described above.

  As described above, according to the touch panel of the present invention, it is possible to reduce the reflected light reflected by the surface of the screen glass other than the detection target from being received by the light receiving unit of the proximity sensor.

It is a figure which shows an example of a structure of the portable information terminal 200 provided with the touchscreen which concerns on one Embodiment. It is a figure which shows an example of the external appearance of the portable information terminal. It is a figure which shows an example of a structure of the vicinity of the proximity sensor 100 in the touchscreen which concerns on other embodiment. FIG. 3 is a diagram illustrating an example of components constituting the proximity sensor 100 and an example of a footprint of a substrate 104. It is a figure which shows an example of a structure of the vicinity of the proximity sensor 1000 in the touchscreen which concerns on other embodiment. An example of the structure of the vicinity of the proximity sensor 1100 in the touchscreen which concerns on other embodiment is shown. It is a figure which shows an example of a structure of the vicinity of the proximity sensor 300 in a common touch panel. It is a figure which shows an example of a structure of the vicinity of the proximity sensor 300 in a common touch panel. It is a figure which shows an example of a structure of the vicinity of the proximity sensor 300 in a common touch panel. It is a figure which shows the relationship between the distance between the detection target object X and a proximity sensor, and the measured value of the intensity | strength of the infrared rays detected by a light-receiving part.

  FIG. 1 shows an example of a configuration of a portable information terminal 200 including a touch panel according to an embodiment. Fig.1 (a) is the figure which attached | subjected the code | symbol only to the essential component which comprises the touchscreen which concerns on this invention. Moreover, FIG.1 (b) is the figure which attached | subjected the code | symbol also to other components other than the essential component to which the code | symbol was attached | subjected in Fig.1 (a). The portable information terminal 200 is a terminal including a touch panel such as a PDA (Personal Data Assistance), a mobile phone, a smartphone, an electronic dictionary, and a notebook computer. The portable information terminal 200 may be an example of a “terminal device” in the present invention.

  The touch panel according to the present invention includes a proximity sensor 100, a screen glass 101, and a substrate 104 as essential components. The proximity sensor 100 is a sensor that measures the amount of light received by the light receiving unit 107 and outputs the measured value. More specifically, the proximity sensor 100 includes a light emitting unit 106 and a light receiving unit 107. The light emitting unit 106 is a light emitting element that emits infrared light. The light receiving unit 107 is a light receiving element that receives infrared rays.

  The touch panel of the portable information terminal 200 further includes a touch panel sensor 102, an LCD (Liquid Crystal Display) 103, a mother substrate 108, a battery 109, a rear case 110, and a front case 111, in addition to the above essential components. Here, a protective sheet 813 as shown in FIG. 9 may be attached to the screen glass 101. Further, the rear case 110 and the front case 111 may be made of the same material, or may be an integral structure. The substrate 104 may be integrated with a substrate (not shown) on the touch panel sensor 102 side.

  The screen glass 101 may be provided with an infrared antireflection film 105 that suppresses and transmits infrared rays at the glass / air interface. A decorative print 112 may be applied around the infrared antireflection film 105. In that case, the proximity sensor 100 is disposed immediately below the infrared antireflection film 105.

  The back surface of the substrate 104 is attached to the screen glass 101. In addition, on the surface of the substrate 104, a light receiving / emitting surface including the lens of the light emitting unit 106 of the proximity sensor 100 and the lens of the light receiving unit 107 is provided in proximity. In the substrate 104, through holes are formed at locations corresponding to the light emitting unit 106 and the light receiving unit 107, respectively. As a result, infrared light emitted from the light emitting unit 106 passes through the through hole corresponding to the light emitting unit 106. Similarly, the infrared reflected light passes through the through hole corresponding to the light receiving unit 107 and is received by the light receiving unit 107.

  In addition, a CPU (Central Processing Unit) (not shown) on the mother board 108 controls the proximity sensor 100 and grasps a measured value of the received light amount measured by the proximity sensor 100. The CPU and the proximity sensor 100 are supplied with power from the battery 109.

  In general, the intensity of emitted light from an LED (Light Emitting Diode) constituting the light emitting unit 106 of the proximity sensor 100 is strong in the center and weak in the periphery. Further, the emitted light of the LED is reflected and diffusely reflected at the boundary surface or the like (hereinafter, both are simply referred to as reflection, and the reflected light is referred to as reflected light). Therefore, as described above, in the case where the proximity sensor is provided with a large distance from the screen glass, such as a proximity sensor in a touch panel having a general configuration, the light receiving unit of the proximity sensor is from various places of the portable information terminal. The reflected light is also received.

  On the other hand, the touch panel of this embodiment has a light receiving / emitting surface provided with the lens of the light emitting unit 106 of the proximity sensor 100 and the lens of the light receiving unit 107 attached to the substrate 104 attached to the screen glass 101. Yes. Therefore, the unintended reflected light reflected at the boundary does not reach the light receiving unit 107 but reaches a portion close to the light emitting unit 106. Therefore, in the touch panel of the present embodiment, unnecessary detection of reflected light can be reduced, and malfunction of the proximity sensor 100 can be prevented. A part of the light emitted from the light emitting unit 106 is reflected at the interface of the screen glass 101 or the like, but the reflected light is mainly due to the short distance between the light emitting unit 106 and the interface of the screen glass 101 or the like. The light that hits the flexible substrate 104 and reaches the light receiving unit 107 by regular reflection or irregular reflection is very small.

  Moreover, in the touch panel of this embodiment, since the proximity sensor 100 is attached to the board | substrate 104 affixed on the screen glass 101, the touch panel sensor 102 and the proximity sensor 100 can also be mounted in the same surface.

  FIG. 2 shows an example of the appearance of the portable information terminal 200. Here, the A-A ′ cross section of FIG. 2 has the structure shown in FIG. 1. The portable information terminal 200 includes a touch panel screen 201, a receiver 203, a microphone 204, a key button 205, and a proximity sensor window 206.

  The surface area of the screen glass 101 is an area of the touch panel screen 201. Further, the proximity sensor window 206 is disposed in the area of the touch panel screen 201.

  FIG. 3 shows an example of a configuration in the vicinity of the proximity sensor 100 in a touch panel according to another embodiment. In the touch panel of this embodiment, a part of the substrate 104 is also present between the light receiving unit 107 and the light emitting unit 106. In the touch panel having such a configuration, the substrate 104 serves as a partition between the light receiving unit 107 and the light emitting unit 106, and can be made less susceptible to the influence of reflected light.

  Infrared rays irradiated from the light emitting unit 106 of the proximity sensor 100 pass through the screen glass 101 and reach the detection target X. Then, the infrared rays that have reached the detection target X are reflected by the surface of the detection target X. The reflected light 508 reaches the light receiving unit 107 of the proximity sensor 100. On the other hand, among the infrared rays irradiated from the light emitting unit 106 of the proximity sensor 100, the infrared ray 509 reflected on the surface of the screen glass 101 has a small distance between the screen glass 101 and the proximity sensor 100. Without reaching the light receiving portion 107, the light receiving portion 107 is reached closer to the light emitting portion 106. The same can be said for the infrared reflection and the like in the case of the touch panel of the embodiment shown in FIG.

  FIG. 10 shows the relationship between the distance between the detection object X and the proximity sensor and the measured value of the intensity of infrared rays detected by the light receiving unit. The measurement value of the intensity of infrared rays detected by the light receiving unit increases as the distance between the detection object X and the proximity sensor becomes shorter. In the graph shown by the solid line in FIG. 10 (in the case of the touch panel shown in FIGS. 1 and 3), the amount of light received by the light receiving unit when the detection target X located at a distance 902 from the proximity sensor is detected is the measured value 901. It has become. On the other hand, in the graph shown by the one-dot chain line in FIG. 10 (in the case of the touch panel shown in FIG. 8) and the graph shown in the broken line (in the case of the touch panel shown in FIG. 9), the detection target X at the same position is detected. At this time, the amount of light received by the light receiving unit is higher than the measured value 901. That is, it can be seen that the touch panel according to the present embodiment does not receive light reflected by an interface or the like other than the detection target object X as compared with a general touch panel.

  FIG. 4 shows an example of components constituting the proximity sensor 100 and an example of the footprint of the substrate 104. FIG. 4A is a plan view of components constituting the proximity sensor 100. FIG. FIG. 4B is a side view of the component. FIG. 4C is a bottom view of the component. A light emitting unit 106, a light receiving unit 107, and a soldering terminal 405 are provided on the upper surface of the components constituting the proximity sensor 100.

  FIG. 4D shows the footprint of the substrate 104. In FIG. 4D, the external shape 406 of the component attached to the board 104 is the external shape of the component of the proximity sensor 100. The soldering land 407 is a land for soldering the terminal 405. Two through holes 408 are formed in the substrate 104. The proximity sensor 100 is attached so that the light receiving unit 107 and the light emitting unit 106 are positioned in the through holes 408, respectively.

  As described above, by forming the through-hole 408 only at the position where the light emitting unit 106 and the light receiving unit 107 are arranged on the substrate 104, the substrate 104 as described above is provided between the light emitting unit 106 and the light receiving unit 107. The partition by will be provided.

  FIG. 5 shows an example of a configuration in the vicinity of the proximity sensor 1000 in a touch panel according to another embodiment. The touch panel of this embodiment uses convex lenses for the light emitting unit 1002 and the light receiving unit 1001 of the proximity sensor 1000. However, the tip of the convex lens is prevented from coming out from the back surface of the substrate 1003. The convex lens can be sandwiched between a part of the substrate 1003. In the touch panel having such a configuration, the directivity of the emitted light is increased in the light emitting unit 1002 and it is difficult for the light receiving unit 1001 to receive incident light from the outside of the optical axis. It is possible to more effectively prevent erroneous detection of light.

  FIG. 6 shows an example of a configuration in the vicinity of the proximity sensor 1100 in a touch panel according to another embodiment. In the touch panel of this embodiment, a substrate 1104 is attached with a double-sided tape 1105 such as black that hardly absorbs and transmits infrared rays. By using a double-sided tape made of such a material, it is possible to make it difficult to transmit infrared light having a low directivity reflected at the interface other than the detection object X. This makes it possible to more effectively prevent erroneous detection of reflected light. Note that an opaque adhesive may be used instead of the double-sided tape 1005.

  A part or all of the above-described embodiment can be described as in the following supplementary notes, but is not limited thereto.

  (Supplementary note 1) Screen glass, a substrate on which the back surface is fixed to the screen glass, a pair of through holes penetrating from the front surface to the back surface is formed, and attached to the surface of the substrate, through one of the through holes A touch panel comprising: a proximity sensor having a light emitting unit that emits infrared light toward the screen glass side and a light receiving unit that receives infrared light from the screen glass side through the other through hole.

  (Additional remark 2) The touchscreen of Claim 1 with which a convex-shaped lens is provided in the light-receiving surface of the said light-receiving part.

  (Additional remark 3) The touchscreen of Claim 1 or 2 with which a convex-shaped lens is provided in the light emission surface of the said light emission part.

  (Appendix 4) The touch panel according to any one of appendices 1 to 3, wherein a protective sheet for protecting the glass surface is attached to the screen glass.

  (Supplementary Note 5) A terminal device including the touch panel according to any one of Supplementary Notes 1 to 4.

100 proximity sensor 101 screen glass 102 touch panel sensor 103 LCD
104 Substrate 105 Infrared antireflection film 106 Light emitting unit 107 Light receiving unit 108 Mother substrate 109 Battery 110 Rear case 111 Front case 112 Decorative printing 201 Touch panel screen 206 Proximity sensor window 1005, 1105 Double-sided tape X Object to be detected

Claims (5)

Screen glass,
A substrate on which the back surface is fixed to the screen glass, and a pair of through holes penetrating from the front surface to the back surface is formed;
A proximity that is attached to the surface of the substrate and has a light emitting part that emits infrared light to the screen glass side through one of the through holes, and a light receiving part that receives infrared light from the screen glass side through the other through hole. A touch panel equipped with a sensor. The touch panel according to claim 1, wherein a convex lens is provided on a light receiving surface of the light receiving unit. The touch panel according to claim 1, wherein a convex lens is provided on a light emitting surface of the light emitting unit. The touch panel according to any one of claims 1 to 3, wherein a protective sheet for protecting the glass surface is attached to the screen glass.   A terminal device provided with the touch panel as described in any one of Claims 1-4.

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