JP6238409B2 - Liquid crystal display - Google Patents

Description

  The present invention relates to a liquid crystal display device including a proximity sensor for activating a screen display when a human finger or the like approaches, or switching a still image display to a moving image display.

  Conventionally, in a liquid crystal display device used for, for example, a car navigation system, a tablet terminal, a smartphone, etc., when a human finger approaches the display screen in order to operate a touch panel provided in the liquid crystal display device, the screen display Or a proximity sensor for switching from still image display to moving image display. As this proximity sensor, there are a capacitance type sensor, an inductance type sensor, etc., but a capacitance that can detect the proximity of a human finger, which is an electrostatic conductor, as a change in capacitance without contact. A type sensor is preferably used.

  An example of a liquid crystal display device provided with a conventional proximity sensor is shown in FIG. FIG. 6 is an exploded plan view showing main components of the liquid crystal display device. The liquid crystal display device includes a liquid crystal display panel 21, a transparent member 22 made of a glass plate or the like covering the display surface of the liquid crystal display panel 21, A flat plate-like backlight 24 installed on the side opposite to the display surface of the liquid crystal display panel 21, and a protective substrate 25 made of a plastic plate or the like installed on the main surface opposite to the liquid crystal display panel 21 of the backlight 24; have. The transparent member 22 is a conductor made of a material such as a metal such as silver, an alloy, or a transparent conductor such as ITO (Indium Tin Oxide) so as to surround the periphery of the liquid crystal display panel 21 on the main surface on the viewer side. A capacitive proximity sensor 26 composed of the line 26b is formed. In FIG. 6, reference numeral 26 a denotes a power feeding unit that supplies a pulse voltage to the capacitive proximity sensor 26, and 23 denotes a frame made of plastic or the like having an opening 23 a for fitting the liquid crystal display panel 21 and fixing the position. is there.

  FIG. 7 is a cross-sectional view of a liquid crystal display device constructed by assembling the main components shown in FIG. As shown in FIG. 7, the transparent member 22, the liquid crystal display panel 21, the backlight 24, the backlight frame 24a, and the liquid crystal display panel 21 are fitted from the viewer side (the side indicated by the white arrow in FIG. 7). A frame 23 having an opening 23a and a protective substrate 25 are disposed. The frame 24a is fitted into the frame 23 and fixed by means such as screwing, and the protective substrate 25 is fixed to the frame 23 by means such as screwing.

  The capacitive proximity sensor 26 of the liquid crystal display device of FIG. 6 operates as follows, for example. First, when an external conductor such as a human finger approaches the conductor line 26b, capacitive coupling occurs between the conductor line 26b and the external conductor. At this time, since a new electric capacity is added to the conductor line 26b, the current value (charge amount) reflected from the conductor line 26b to the external control IC, LSI, etc. connected to the power supply portion 26a changes. To do. By detecting the changed current value as a change in voltage value by a control IC, LSI or the like, the proximity of an external conductor can be detected.

  As another conventional example, an electronic device having a proximity sensor composed of an induction antenna, the proximity sensor having a linear shape, a ring shape, a belt shape, a bellows shape (zigzag shape), a spiral shape, or a wave shape is proposed. (See Patent Document 1).

JP 2013-229000 A

  However, the conventional liquid crystal display device shown in FIGS. 6 and 7 has the following problems. As shown in FIG. 8, the current input from the power feeding portion 26a to the conductor wire portions 26b1 and 26b2 is a magnetic field (FIG. 8) so that the right screw advances in the current direction (the direction indicated by the arrow in FIG. 8) according to the right screw law. 8 (indicated by a white arrow). This dynamic magnetic field induces an electric field, and electromagnetic waves are radiated around each of the conductor wire portions 26b1 and 26b2 based on the induced electric field. Similarly, in the conductor line portions 26b3, 26b4, 26b5, and 26b6, electromagnetic waves are radiated around them. At this time, since the direction of the current flowing through the conductor wire portion 26b1 and the direction of the current flowing through the conductor wire portion 26b2 are opposite directions, the phase of the electromagnetic wave radiated from the conductor wire portion 26b1 and the radiation from the conductor wire portion 26b2 The phase of the electromagnetic wave is opposite to that of the electromagnetic wave, and the electromagnetic waves are canceled and almost no electromagnetic wave is emitted. Further, the same phenomenon occurs between the conductor line portion 26b1 and the conductor line portion 26b5, and between the conductor wire portion 26b2 and the conductor line portion 26b6, so that the electromagnetic waves are canceled and hardly emitted.

  However, since the direction of the current flowing through the conductor wire portion 26b3 and the direction of the current flowing through the conductor wire portion 26b4 are the same, the phase of the electromagnetic wave radiated from the conductor wire portion 26b3 and the radiation from the conductor wire portion 26b4 The phase of the electromagnetic wave becomes the same phase, and the electromagnetic waves are radiated intensifying each other. As a result, there has been a problem that electromagnetic waves radiated in an intensified manner cause EMI (Electromagnetic Interference) in surrounding electronic components, circuit wiring, and the like.

  The present invention has been completed in view of such circumstances, and an object of the present invention is to allow a capacitive proximity sensor provided in a liquid crystal display device to generate EMI in surrounding electronic components, circuit wiring, and the like. It is effective to suppress it.

  The liquid crystal display device of the present invention includes a liquid crystal display panel, a transparent member covering the display surface of the liquid crystal display panel, a backlight installed on the side opposite to the display surface of the liquid crystal display panel, and the liquid crystal display panel. And a protective substrate installed on the main surface of the backlight opposite to the liquid crystal display panel, and at least one of the transparent member, the frame, and the protective substrate. One is a configuration in which linear capacitive proximity sensors extending in opposite directions from the power feeding portion are provided on the peripheral portion of the main surface.

  In the liquid crystal display device of the present invention, it is preferable that the capacitive proximity sensor has the power feeding unit positioned at the center thereof.

  In the liquid crystal display device of the present invention, it is preferable that at least one of the transparent member, the frame, and the protective substrate, in which the capacitive proximity sensor is provided, has a polygonal outer shape and is adjacent to the transparent member. The capacitive proximity sensor is provided on each of the plurality of sides, and the power feeding unit is located at the center of the capacitive proximity sensor.

  In the liquid crystal display device of the present invention, preferably, the protective substrate is provided with the capacitance proximity sensor, and the transparent member is the capacitance type in a plan view at a peripheral portion of the main surface. A capacitive proximity sensor is provided in a portion that does not overlap the proximity sensor.

  In the liquid crystal display device of the present invention, it is preferable that at least one of the transparent member, the frame, and the protective substrate, in which the capacitive proximity sensor is provided, has a polygonal outer shape and is adjacent to the transparent member. The capacitive proximity sensor is provided over a plurality of sides, and the power feeding unit is located at the center of the capacitive proximity sensor in each of the sides.

  In the liquid crystal display device according to the present invention, preferably, the frame has a polygonal outer shape, and the capacitive proximity sensor is provided over a plurality of adjacent sides, and the static proximity sensor is provided on each of the sides. A current supply unit is provided at the center of the capacitive proximity sensor, and the protective substrate is provided with a power supply unit at a position corresponding to the current supply unit, and the power supply unit is connected to the current supply unit. Has been.

  The liquid crystal display device of the present invention includes a liquid crystal display panel, a transparent member that covers the display surface of the liquid crystal display panel, a backlight installed on the side opposite to the display surface of the liquid crystal display panel, and a liquid crystal display panel for fitting A frame having an opening, and a protective substrate installed on the main surface opposite to the liquid crystal display panel of the backlight, and at least one of the transparent member, the frame, and the protective substrate has the main surface Since the linear capacitive proximity sensor extending in the opposite direction from the power supply unit is formed at the peripheral portion, the direction of the current supplied from the power supply unit to the capacitive proximity sensor is viewed from the power supply unit. They are in opposite directions. As a result, the phase of the electromagnetic wave radiated from the capacitive proximity sensor extending from the power supply part to the one side is opposite to the phase of the electromagnetic wave radiated from the capacitive proximity sensor extending from the power supply part to the other side, These electromagnetic waves cancel each other and almost no electromagnetic waves are emitted.

  In the liquid crystal display device of the present invention, it is preferable that the capacitive proximity sensor is radiated from the capacitive proximity sensor extending to one side from the feeding unit because the feeding unit is located at the center. The intensity and the radiation range of the electromagnetic wave and the electromagnetic wave emitted from the capacitive proximity sensor extending from the power supply unit to the other are the same, and the cancellation of these electromagnetic waves is performed more effectively.

  In the liquid crystal display device of the present invention, it is preferable that at least one of the transparent member, the frame, and the protective substrate in which the capacitive proximity sensor is provided has a polygonal outer shape and a plurality of adjacent sides. Each of which is provided with a capacitive proximity sensor, and the power feeding unit is located at the center of the capacitive proximity sensor. For example, sensing is performed for all directions around the liquid crystal display device. Can be performed.

  In the liquid crystal display device of the present invention, preferably, the protective substrate is provided with a capacitive proximity sensor, and the transparent member overlaps the capacitive proximity sensor in plan view at the peripheral portion of the main surface. Since the capacitive proximity sensor is provided in the part that does not become a sensor, it is possible to perform sensing in all directions around the liquid crystal display device, and the capacitive proximity sensor provided on the protective substrate And the capacitive proximity sensor provided on the transparent member are not on the same plane, and electromagnetic waves radiated from them are prevented from interfering and strengthening.

  In the liquid crystal display device of the present invention, it is preferable that at least one of the transparent member, the frame, and the protective substrate in which the capacitive proximity sensor is provided has a polygonal outer shape and a plurality of adjacent sides. A capacitive proximity sensor is provided over the entire area, and the power feeding unit is located at the center of the capacitive proximity sensor on each side, so that sensing is possible in all directions around the liquid crystal display device. Can be performed.

  In the liquid crystal display device of the present invention, it is preferable that the frame has a polygonal outer shape and is provided with a capacitive proximity sensor over a plurality of adjacent sides, and each of the sides has a capacitive proximity. A current supply unit is provided in the center of the sensor, and the protective substrate is provided with a power supply unit at a position corresponding to the current supply unit and the power supply unit is connected to the current supply unit. In addition, the linear capacitive proximity sensor can be formed wider and separately from the power supply unit, and the sensing area can be increased by increasing the electrode area of the capacitive proximity sensor.

FIG. 1 is a diagram showing an example of an embodiment of a liquid crystal display device according to the present invention, and is a plan view showing exploded main components of the liquid crystal display device. 2A is a plan view for explaining cancellation of electromagnetic waves in the capacitive proximity sensor formed on the protective substrate of the liquid crystal display device of FIG. 1, and FIG. 2B is a plan view of the liquid crystal display device of FIG. It is a top view for demonstrating cancellation of the electromagnetic waves in the other capacitive proximity sensor formed in the transparent member. FIG. 3 is a diagram showing another example of the embodiment of the liquid crystal display device of the present invention, and is a plan view showing the main components of the liquid crystal display device in an exploded manner. FIG. 4 is a diagram showing another example of the embodiment of the liquid crystal display device of the present invention, and is a plan view showing the main components of the liquid crystal display device in an exploded manner. FIGS. 5A and 5B are diagrams showing another example of the embodiment of the liquid crystal display device of the present invention, and FIG. 5A is an electrostatic diagram in which the front end side is a laminated structure and electrical resistance is reduced. FIG. 5B is a cross-sectional view of a capacitive proximity sensor, and FIG. 5B is a cross-sectional view of a capacitive proximity sensor in which the tip side is made of a low-resistance material to reduce electrical resistance. FIG. 6 is a diagram illustrating an example of a conventional liquid crystal display device, and is a plan view illustrating the main components of the liquid crystal display device in an exploded manner. FIG. 7 is a cross-sectional view of a liquid crystal display device constructed by assembling the main components shown in FIG. FIG. 8 is a plan view for explaining the radiation of electromagnetic waves in the capacitive proximity sensor formed on the transparent member of the liquid crystal display device of FIG.

  Hereinafter, embodiments of a liquid crystal display (LCD) of the present invention will be described with reference to the drawings. However, each drawing referred to below shows a main part for explaining the liquid crystal display device of the present invention among the constituent members in the embodiment of the liquid crystal display device of the present invention. Therefore, the liquid crystal display device according to the present invention can include well-known components such as a circuit board, a wiring conductor, a control IC, and an LSI not shown in the drawing.

  FIG. 1 is a diagram showing an example of an embodiment of a liquid crystal display device according to the present invention, and is a plan view showing exploded main components of the liquid crystal display device. The liquid crystal display device of the present invention includes a liquid crystal display panel 1, a transparent member 2 made of a glass plate, a plastic plate, or the like that covers the display surface of the liquid crystal display panel 1, and a non-display surface (opposite to the display surface) of the liquid crystal display panel 1. A flat plate-like backlight 4 installed on the side), a frame 3 made of an insulator such as plastic having an opening 3a for fitting the liquid crystal display panel 1, metal, etc., and a backlight 4 and a protective substrate 5 made of a plastic substrate, a glass substrate or the like installed on the main surface opposite to the liquid crystal display panel 1. Then, at least one of the transparent member 2, the frame 3, and the protective substrate 5, the conductor wires 7b, 7b, 8b, 8b, 9b extending in the opposite directions from the power feeding portions 7a, 8a, 9a to the peripheral portion of the main surface. , 9b are provided as linear capacitive proximity sensors 7, 8, and 9. In FIG. 1, 4a is a frame (frame) made of aluminum or the like that protects the outer periphery of the backlight 4, 7c, 8c, 9c are feeders, 10 is a capacitance type proximity having a control IC, LSI, etc. This is a circuit board for controlling the sensors 7, 8 and 9.

  With this configuration, the directions of the currents supplied from the power supply unit 7a to the conductor wires 7b and 7b of the capacitive proximity sensor 7 are opposite to each other as viewed from the power supply unit 7a. As a result, the conductor extends from the power supply unit 7a to one side. The phase of the electromagnetic wave radiated from the line 7b and the phase of the electromagnetic wave radiated from the conductor line 7b extending from the power supply portion 7a to the other are opposite to each other, and these electromagnetic waves are canceled out and almost no electromagnetic wave is emitted. The capacitive proximity sensors 8 and 9 have the same effect. In order to achieve such an effect, a linear capacitive proximity sensor 7 composed of conductor wires 7b, 7b, 8b, 8b, 9b, 9b extending in opposite directions from the power feeding portions 7a, 8a, 9a, 8 and 9 are configured such that one conductor wire 7b, 8b, 9b and the other conductor wire 7b, 8b, 9b do not substantially include a parallel portion having the same current direction. For example, one conductor line 7b, 8b, 9b and the other conductor line 7b, 8b, 9b are configured to form substantially one straight line.

  The liquid crystal display panel 1 of the present invention has the following configuration, for example. A TFT array side substrate on which a large number of pixel electrode portions including thin film transistor elements are formed and a color filter side substrate on which a color filter and a black matrix are formed are opposed to each other, and the substrates are separated by a predetermined distance. Thus, the substrates are bonded together, and liquid crystal is filled and sealed between the substrates. In general, the color filter side substrate is a common electrode (reference electrode) for forming a vertical electric field to be applied to the liquid crystal with the pixel electrode on the entire main surface facing the TFT element and the pixel electrode. ) Is formed. Further, red (R), green (G), and blue (B) color filters corresponding to the respective pixels are formed on the main surface of the color filter side substrate, and light passing through the respective pixels is transmitted. A black matrix that prevents mutual interference is formed so as to surround the outer periphery of the color filter.

  As the liquid crystal display panel 1, various types such as a TN (Twisted Nematic) type, an IPS (In-Plane Switching) type, and an FFS (Fringe Field Switching) type can be adopted.

  Such a liquid crystal display device is provided with a backlight 4 on the side opposite to the viewer side, through which transmitted light for forming an image on the liquid crystal display panel 1 is incident from the back side of the liquid crystal display panel 1. There are two types of the backlight 4. One method is an edge light method in which an LED (Light Emitting Diode) element as a light emitting element is arranged at the edge of the screen of the liquid crystal display panel 1. In this edge light system, light from LED elements arranged at the edge of the screen of the liquid crystal display panel 1 is guided to the entire screen by the light guide plate and uniformly dispersed. The edge light system can maintain good optical uniformity on a screen of up to about 60 inches and can realize a backlight 4 having a thickness of about 5 to 10 mm.

  The other type is a direct type, in which a large number of LED elements are arranged directly under a liquid crystal pixel, and light from the LED element is directly incident on the pixel. This direct type has no limitation on the screen size of the liquid crystal display panel 1 to which it is applied, and has low power consumption and good heat dissipation. The direct type has a tendency to make the backlight device thicker than the edge light method, but it can be suppressed to a thickness of about 10 mm or less. As a driving method for light emission of the LED element, a driving method for inputting a pulse current to the LED element by a PWM (Pulse Width Modulation) method is generally used.

  Capacitive proximity sensors 7, 8, 9 comprising conductor wires 7b, 7b, 8b, 8b, 9b, 9b are gold (Au), silver (Ag), copper (Cu), aluminum (Al), chromium ( It is made of a material such as a metal such as Cr), nickel (Ni), iron (Fe), an alloy containing these metals, or a transparent conductor such as ITO. For example, when the capacitive proximity sensors 7, 8, 9 are made of silver, a silver paste in which a predetermined amount of silver particles is mixed into a paste containing alcohol, liquid resin, etc. is applied, dried, and baked to obtain a static Capacitive proximity sensors 7, 8, 9 can be provided. In addition to this coating / firing method, it can also be provided by a thin film forming method such as a plating method, a vapor deposition method, a CVD (Chemical Vapor Deposition) method, or a sputtering method. Furthermore, the capacitive proximity sensors 7, 8, 9 may be conductor members or metal members produced by sheet metal processing. The feeder lines 7c, 8c, and 9c can also be provided in the same manner as the capacitive proximity sensors 7, 8, and 9.

  The capacitive proximity sensors 7, 8, 9 of the liquid crystal display device of the present invention operate as follows, for example. First, when an external conductor such as a human finger comes close to the conductor lines 7b, 8b, 9b, electrical capacitive coupling occurs between the conductor lines 7b, 8b, 9b and the external conductor. At this time, since a new electric capacity is added to the conductor lines 7b, 8b, 9b, the control IC of the circuit board 10 connected to the power supply portions 7a, 8a, 9a through the power supply lines 7c, 8c, 9c, The current value (charge amount) reflected from the conductor lines 7b, 8b, 9b changes to the LSI or the like. By detecting the changed current value as a change in voltage value by a control IC, LSI or the like, the proximity of an external conductor can be detected.

  2A is a plan view for explaining cancellation of electromagnetic waves in the capacitive proximity sensors 7, 8, and 9 provided on the protective substrate 5 of the liquid crystal display device of FIG. 1, and FIG. It is a top view for demonstrating cancellation of the electromagnetic waves in the other capacitive proximity sensor 6 provided in the transparent member 2 of 1 liquid crystal display device. As shown in FIG. 2A, in the capacitive proximity sensor 7, the current input to the conductor wires 7b and 7b from the power feeding portion 7a is the current direction (the direction indicated by the arrow in FIG. 2) according to the right screw law. ) To generate a magnetic field (indicated by a white arrow in FIG. 2) so that the right screw advances. This dynamic magnetic field induces an electric field, and based on this, electromagnetic waves are radiated around each of the conductor wires 7b and 7b. At this time, since the direction of the current flowing through one conductor line 7b and the direction of the current flowing through the other conductor line 7b are opposite, the phase of the electromagnetic wave radiated from one conductor line 7b and the other conductor line 7b The phases of the electromagnetic waves radiated from the phase are opposite to each other, the electromagnetic waves are canceled out, and the electromagnetic waves are hardly radiated. The capacitive proximity sensors 8 and 9 also have the same effect as the capacitive proximity sensor 7. Further, as shown in FIG. 2B, the capacitive proximity sensor 6 has the same effect as the capacitive proximity sensor 7.

  The capacitive proximity sensor 6 shown in FIG. 2 (b) has conductor wires 6b and 6b extending in opposite directions from the two power feeding portions 6a and 6a, and the conductor wires 6b and 6b are connected to the conductor wires 6b and 6b. The effects of the present invention described above can be obtained by inputting currents simultaneously.

  In the capacitive proximity sensors 8 and 9, the direction of the current flowing through one conductor line 8b and 9b and the direction of the current flowing through the other conductor line 8b and 9b may not be diametrically opposite directions, but substantially opposite directions. If it is. In other words, the angle (θ) between the direction of the current flowing through one conductor line 8b, 9b and the direction of the current flowing through the other conductor line 8b, 9b is not 180 degrees, but the angle θ is not necessarily It does not have to be 180 degrees. In order to achieve the effects of the present invention described above, the angle θ should be in the range of about 150 to 180 degrees.

  The effects of the present invention described above can also be obtained with respect to the feeder lines 8c and 9c. That is, as shown in FIG. 2A, the direction of the current flowing through the power supply line 8c and the direction of the current flowing through the power supply line 9c may be substantially opposite (substantially opposite directions). However, in the case where there are no two feeding lines in which the directions of the flowing currents are opposite to each other like the feeding line 7c shown in FIG. 2A, the length of the feeding line 7c is such that the direction of the flowing current is It is preferably shorter than the two feeder lines 8c and 9c that are in opposite directions. Thereby, even if electromagnetic waves are radiated from the feeder line 7c, the intensity and radiation range can be suppressed.

  Further, in the liquid crystal display device of the present invention, it is preferable that the capacitive proximity sensors 7, 8, 9 have power feeding portions 7 a, 8 a, 9 a located at the center thereof. In this case, the strength and radiation range of the electromagnetic waves radiated from the conductors 7a, 8a, 9a to the one side and the conductor lines 7b, 8b, 9b extending from the feeders 7a, 8a, 9a to the other side The intensity and the radiation range of the electromagnetic waves radiated from 9b become the same, and the cancellation of those electromagnetic waves is performed more effectively.

  In the liquid crystal display device of the present invention, at least one of the transparent member 2, the frame 3, and the protective substrate 5 provided with the capacitive proximity sensor has a polygonal outer shape and a plurality of adjacent sides. Each is provided with a capacitive proximity sensor, and the power feeding unit is preferably located at the center of the capacitive proximity sensor. FIG. 2 (a) shows an example. The protective substrate 5 has a substantially rectangular outer shape, and capacitive proximity sensors 7, 8, 9 are provided on each of the three adjacent sides. The power feeding portions 7 a, 8 a, and 9 a are formed at the center of the capacitive proximity sensors 7, 8, and 9. In this case, it is possible to perform sensing with respect to three directions around the liquid crystal display device.

  Further, in the liquid crystal display device of the present invention, as shown in FIGS. 2A and 2B, the protective substrate 5 is provided with capacitive proximity sensors 7, 8, and 9, and the transparent member 2 is It is preferable that the capacitive proximity sensor 6 is provided in a portion that does not overlap with the capacitive proximity sensors 7, 8, 9 in a plan view in the peripheral portion of the main surface. In this case, sensing can be performed in all directions around the liquid crystal display device, and the capacitive proximity sensors 7, 8, 9 provided on the protective substrate 5 and the transparent member 2 are provided. Since the capacitive proximity sensor 6 is not on the same plane, electromagnetic waves radiated from them can be prevented from interfering and strengthening.

  In the liquid crystal display device of the present invention, at least one of the transparent member 2, the frame 3, and the protective substrate 5 provided with the capacitive proximity sensor has a polygonal outer shape and a plurality of adjacent sides. It is preferable that a capacitive proximity sensor is provided over the entire area, and the power feeding unit is located at the center of the capacitive proximity sensor at each side. In this case, it is possible to perform sensing for all directions around the liquid crystal display device. FIG. 3 is a diagram showing an example thereof, and is a plan view showing the main components of the liquid crystal display device in an exploded manner. In the example of FIG. 3, the protective substrate 5 on which the capacitive proximity sensors 7, 8, and 9 are provided has a substantially rectangular outer shape and the capacitive proximity sensors 7, 8 over three adjacent sides. , 9 are provided, and the power feeding parts 7a, 8a, 9a are located at the center of the capacitive proximity sensors 7, 8, 9 on each of the sides. That is, the capacitive proximity sensors 7, 8, 9 are connected to form a series. In this case, the effects of the present invention described above can be obtained by simultaneously making the input timings of the currents input to the power feeding units 7a, 8a, and 9a.

  Further, in the liquid crystal display device of the present invention, the frame 3 has a polygonal outer shape and is provided with a capacitive proximity sensor over a plurality of adjacent sides. It is preferable that a current supply unit is provided at the center, and that the protective substrate 5 is provided with a power supply unit at a position corresponding to the current supply unit, and the power supply unit is connected to the current supply unit. In this case, for example, a linear capacitive proximity sensor can be formed wide and separately from the power feeding unit, and the sensitivity of sensing can be improved by increasing the electrode area of the capacitive proximity sensor. it can. FIG. 4 shows an example thereof, and is a plan view showing the main components of the liquid crystal display device in an exploded manner. In the liquid crystal display device shown in FIG. 4, the frame 3 has a substantially rectangular outer shape, and a capacitive proximity sensor 11 is provided over a plurality of adjacent sides, and the capacitive proximity sensor is provided at each of the sides. 11, current supply units 12, 13, 14 are provided, and the protective substrate 5 is provided with power supply units 7 a, 8 a, 9 a at positions corresponding to the current supply units 12, 13, 14. The power supply units 7a, 8a, and 9a are connected to the current supply units 12, 13, and 14. With this configuration, for example, the linear capacitive proximity sensor 11 can be formed wider and separately from the power feeding units 7a, 8a, and 9a, and the electrode area of the capacitive proximity sensor 11 can be increased. Sensitivity of sensing can be improved.

  In the liquid crystal display device shown in FIGS. 1 to 4, a conductor plate made of a metal such as aluminum or a metal plate, a metal sheet, a metal film or the like is attached to the main surface of the backlight 4 on the protective substrate 5 side. It is preferable to install an insulating plate such as a plastic plate having a metal surface. In this case, the slight electromagnetic waves leaking from the capacitive proximity sensors 7, 8, 9 and the feeder lines 7c, 8c, 9c can suppress EMI to the LED element driven by the PWM method.

  With respect to the liquid crystal display device of the present invention shown in FIGS. 1, 3, and 4 and the conventional liquid crystal display device shown in FIG. 6, the intensity of electromagnetic waves radiated from the liquid crystal display device was measured. As the capacitive proximity sensors 6 to 9 in the liquid crystal display device of the present invention, conductor wires 6b to 9b formed by coating copper wires with a resin insulating material were used, and the wire diameter was 0.5 mm. A capacitance type proximity sensor 26 in a conventional liquid crystal display device was formed by a sputtering method, and its thickness was about 100 nm. The peak value of the pulse voltage input to the capacitive proximity sensors 6 to 9 and 26 is 1 V, the pulse width is 1 μs (s: second), and the input frequency is 1 MHz. Under this condition, the intensity of the electromagnetic wave emitted from the liquid crystal display device of the present invention was −10 dB (1/10) with respect to the intensity of the electromagnetic wave emitted from the conventional liquid crystal display device.

  FIGS. 5A and 5B are diagrams showing another example of the embodiment of the liquid crystal display device of the present invention. FIG. 5A is an electrostatic diagram in which the electrical resistance is reduced with the tip side being a laminated structure. FIG. 5B is a cross-sectional view of the capacitive proximity sensor 32, and FIG. 5B is a cross-sectional view of the capacitive proximity sensor 33 in which the tip side is made of a low-resistance material to reduce electrical resistance. As shown in FIG. 5A, a capacitive proximity sensor is formed by reducing the electrical resistance by increasing the cross-sectional area of the tip end side of the conductor wire 32b of the capacitive proximity sensor 32 as a laminated structure. It is possible to suppress the peak value (peak value) of the pulse voltage from slightly decreasing due to the resistance at the tip end side of 32. Thereby, it is possible to suppress a decrease in sensing sensitivity of the capacitive proximity sensor 32. In order to make the tip side of the capacitive proximity sensor 32 have a laminated structure of two or more layers, for example, by applying and baking silver paste a plurality of times, or forming a thin film by sputtering or the like a plurality of times. Can be done by. In FIG. 5A, reference numeral 32a denotes a power feeding unit. The thickness of the one layer portion on the power feeding portion 32a side of the capacitive proximity sensor 32 is about 10 nm to 1000 nm when formed by sputtering.

  As shown in FIG. 5B, the proximity of the capacitive proximity sensor 33 is made of a material having a lower resistance than that of the power feeding portion 33a so that the electrical resistance is reduced. It is possible to suppress the peak value (peak value) of the pulse voltage from slightly decreasing due to the resistance at the front end side of the sensor 33. As a result, a decrease in sensing sensitivity of the capacitive proximity sensor 33 can be suppressed. In order to configure the tip side of the capacitive proximity sensor 33 with a material having a resistance lower than that of the power feeding portion 33a, for example, when the capacitive proximity sensor 33 is provided by applying and baking silver paste, The ratio of the silver particles contained in the silver paste applied to the tip side of the capacitive proximity sensor 33 is made higher than the ratio of the silver particles contained in the silver paste applied to the power supply part 33a side of the capacitive proximity sensor 33. Can be done.

  The liquid crystal display device of the present invention can activate the screen display when a human finger or the like approaches the liquid crystal display panel 1 or switch the still image display to the moving image display by the above-described capacitive proximity sensor. . In addition, the brightness of the display screen can be increased. Further, when the liquid crystal display device includes a touch panel, the touch panel can be changed from the operation pause state to the operable state.

  When the liquid crystal display device is equipped with a touch panel, the touch panel includes a matrix switch method, a resistive film method, a surface acoustic wave method (ultrasonic method), an infrared method, an electromagnetic induction method, a surface type capacitance method, and a projection type. Various types such as a capacitance type can be adopted. Of these, the surface capacitance type is suitably used for touch panels of 10 inches or more. The capacitance detection unit in the surface type capacitive touch panel is composed of, for example, three layers of a transparent coating layer, a transparent conductive film, and a glass substrate, and the transparent conductive film is an electrode provided on four even portions of the glass substrate. Connected to. A uniform electric field is formed on the surface of the transparent coating layer on the glass substrate by the transparent conductive film. When an electrostatic conductor such as a human finger touches the surface of the capacitance detection unit, a weak current from the drive circuit passes through the electrodes at the four corners, the transparent conductive film, the transparent coating layer, and the finger. Thus, a closed circuit is formed in an equivalent circuit between the surrounding environment such as the ground and the drive circuit. The position of a finger or the like can be determined by calculating the ratio of currents at the electrodes at the four corners by the drive circuit. A surface-type capacitive touch panel can be manufactured at low cost because of its simple structure, and is suitably used for a large touch panel.

  A projected capacitive touch panel can detect multiple points of contact with a finger or the like. For example, a capacitance detection unit in a projected capacitive touch panel has a transparent insulator layer, a transparent electrode layer below it, and a substrate such as a glass substrate on which a drive circuit such as a control IC or control LSI is mounted. Comprising. The transparent electrode layer is formed so as to extend in a predetermined direction, and has a first layer having a mosaic first detection electrode pattern made of ITO or the like, and is orthogonal to the predetermined direction below the first layer. And a second layer having a mosaic-like second detection electrode pattern made of ITO or the like formed so as to extend in the direction in which it is formed. When an electrostatic conductor such as a human finger touches the surface of the capacitance detection unit, by detecting a change in capacitance of about 1 pF in the first and second detection electrode patterns in the vicinity thereof, The position of the contact portion can be detected two-dimensionally with high accuracy. Since the number of electrode terminals connected to the first and second detection electrode patterns is large, the manufacturing cost is increased. Moreover, since the electrical resistance of the first and second detection electrode patterns made of ITO or the like increases as the length increases, the resistance can be reduced by connecting to the metal wiring, and the size can be increased. This projected capacitive touch panel is capable of multipoint detection with a control IC, control LSI, etc. for detecting the position of the contact portion, and has high practicality. Therefore, the projected capacitive touch panel is preferably used for a tablet-type portable terminal or the like. it can.

  In addition, since the projected capacitive touch panel detects a change in capacitance in the first and second detection electrode patterns, an electrostatic conductor such as a human finger is attached to the capacitance detection unit. Even in the case of proximity without directly touching the surface, the position of the proximity portion can be detected two-dimensionally with high accuracy.

  It goes without saying that the liquid crystal display device of the present invention is not limited to the above-described embodiment, and includes appropriate design changes and improvements. For example, in the example of the above embodiment, an example in which a linear capacitive proximity sensor is provided on a side of a substantially rectangular protective substrate or the like included in a substantially rectangular liquid crystal display device has been shown. Depending on the shape of the liquid crystal display device, a curved capacitive proximity sensor that does not impair the effects of the present invention, and a capacitive proximity sensor having a bent portion in the middle may be provided.

  Although the liquid crystal display device has been described in the above embodiment, the capacitive proximity sensor of the present invention may be applied to other display devices. For example, organic EL (Electro Luminescence) display device, inorganic EL display device, FED (Field Emitting Display) display device, SED (Surface-conduction Electron-emitter Display) display device, GLV (Grating Light Valve) display device, PDP (Plasma) Display devices such as a display device, an electronic paper display device, a DMD (digital micro mirror device) display device, and a piezoelectric ceramic display device can be used.

  The liquid crystal display device of the present invention can be applied to various electronic devices. The electronic devices include a digital display wristwatch, a car route guidance system (car navigation system), a ship route guidance system, an aircraft route guidance system, a smartphone terminal, a mobile phone, a tablet terminal, a personal digital assistant (PDA), a video camera, Digital still camera, electronic notebook, electronic book, electronic dictionary, personal computer, copying machine, terminal device of game machine, television, product display tag, price display tag, industrial programmable display device, car audio, digital audio player, There are facsimiles, printers, automatic teller machines (ATMs), vending machines, and the like.

DESCRIPTION OF SYMBOLS 1 Liquid crystal display panel 2 Transparent member 3 Frame 4 Backlight 5 Protective substrate 6, 7, 8, 9 Capacitance type proximity sensor 6a, 7a, 8a, 9a Feed part 6b, 7b, 8b, 9b Conductor line 7c, 8c, 9c Feed line 10 Circuit board 11 Capacitive proximity sensor

Claims (6)

  A liquid crystal display panel, a transparent member covering the display surface of the liquid crystal display panel, a backlight installed on the side opposite to the display surface of the liquid crystal display panel, and a frame having an opening for fitting the liquid crystal display panel; A protective substrate installed on a main surface opposite to the liquid crystal display panel of the backlight, and at least one of the transparent member, the frame, and the protective substrate, and a peripheral edge of the main surface A liquid crystal display device in which linear capacitive proximity sensors extending in opposite directions from a power feeding portion are formed in a portion.   The liquid crystal display device according to claim 1, wherein the power supply unit is located at a central portion of the capacitive proximity sensor.   At least one of the transparent member, the frame, and the protective substrate in which the capacitive proximity sensor is provided has a polygonal outer shape, and the capacitive proximity to each of a plurality of adjacent sides. 3. The liquid crystal display device according to claim 1, wherein a sensor is provided, and the power feeding unit is located at a central portion of the capacitive proximity sensor.   The protective substrate is provided with the capacitive proximity sensor, and the transparent member is disposed at a position where it does not overlap with the capacitive proximity sensor in a plan view at a peripheral portion of the main surface thereof. The liquid crystal display device according to claim 1, wherein the liquid crystal display device is formed.   At least one of the transparent member, the frame, and the protective substrate on which the capacitive proximity sensor is provided has a polygonal outer shape, and the capacitive proximity sensor extends over a plurality of adjacent sides. 3. The liquid crystal display device according to claim 1, wherein the power supply unit is provided at a central portion of the capacitive proximity sensor in each of the sides.   The frame has a polygonal outer shape and is provided with the capacitive proximity sensor over a plurality of adjacent sides, and a current supply unit is provided at the center of the capacitive proximity sensor in each of the sides. The liquid crystal display device according to claim 5, wherein the protective substrate is provided with a power supply unit at a position corresponding to the current supply unit, and the power supply unit is connected to the current supply unit.