JP5412821B2 - Liquid crystal display - Google Patents

Description

The present invention relates to a liquid crystal display device, and more particularly to a liquid crystal display device in which a front surface of a casing exposes a screen of a liquid crystal panel.

  Cost reduction in product development is always a required issue, and at the same time, maintaining or improving performance is also required. Liquid crystal display devices are also being studied for cost reduction from various angles, and devices such as sharing parts and improving development efficiency by reducing assembly man-hours are being accumulated every day.

As an example of device sharing, Patent Document 1 discloses a configuration of a liquid crystal television in which a television receiving circuit and a liquid crystal panel driving device are mounted on the same substrate. In Patent Document 2, a timing generator, a vertical driver, a horizontal driver, a signal processing circuit, and a voltage conversion circuit are provided on the periphery of the liquid crystal display surface of the glass substrate on which the liquid crystal display surface is formed by COG (Chip On Glass). Direct implementation is disclosed. Patent Document 3 discloses a liquid crystal module in which a controller / bare chip and a light receiving element for detecting external light are mounted on liquid crystal glass.
JP 58-172977 Japanese Patent Laid-Open No. 11-88803 JP-A-8-9010

  By the way, a liquid crystal panel is often produced as a liquid crystal module in a state in which a backlight, a source driver substrate, a gate driver substrate, and the like are incorporated. That is, by making components as liquid crystal modules, it is possible to produce general-purpose liquid crystal modules, and by separating the liquid crystal module production process from the liquid crystal display device assembly process, it is possible to prevent an increase in the length of the production line. Against this background, liquid crystal modules tend to be optimized in a form that can be produced at the lowest cost with a single liquid crystal module.

As an example of the optimized liquid crystal module towards the low cost, there is accommodating them metal frame in a state in which the source driver board is disposed on the upper side of the liquid crystal panel and the backlight. In a liquid crystal module optimized in advance as a single module, a substrate on which drive circuits for drive lines such as data lines and source lines of the liquid crystal panel are mounted needs to have substantially the same width as the width of the liquid crystal panel. Therefore, the wiring density of the substrate tends to be low, and it cannot be said that the substrate is effectively utilized.

  The present invention proposes effective use of a substrate on which a circuit for driving a liquid crystal panel is mounted, and an object thereof is to provide a liquid crystal display device capable of improving development efficiency and reducing costs.

In order to solve the above problems, in the liquid crystal display device according to claim 1 of the present invention, in the liquid crystal display device in which the rear surface of the liquid crystal panel is covered with a metal case, and the front surface of the housing exposes the screen of the liquid crystal panel. Provided outside the metal case, the drive data of the drive line of the liquid crystal panel is inputted from the main board via the first cable, and the board is connected to the drive line via the second cable. the substrate, the which element to be exposed is mounted from the housing an element excluding the liquid crystal panel, the portion of the front Kimoto child does not face the on-board surface to the front surface of the liquid crystal panel It arrange | positions toward the inner surface of the front surface of the said housing | casing, and is set as the structure by which the hole for exposing the said element to the exterior is formed in the front surface of the said housing | casing.

In the above configuration, a circuit for generating drive data for driving the liquid crystal panel based on a video signal is mounted on the main board. The drive data generated by the circuit is output to the substrate outside the metal case via the first cable. Here, the drive data includes at least information indicating which of a plurality of liquid crystal elements constituting the liquid crystal panel is opened and information indicating timing of opening, and information indicating the aperture ratio of the liquid crystal element. May be included. The information indicating the aperture ratio corresponds to so-called gradation data. The liquid crystal panel and the substrate are connected via the second cable, and the liquid crystal panel is driven based on the drive data transmitted via the second cable.
On the substrate configured as described above, an element exposed to the outside from the casing is mounted. Implemented surface of the element is placed toward the inner surface of the front surface of the housing of the portion not facing the front surface of the liquid crystal panel. According to the above configuration, it is possible to effectively utilize the substrate as a mounting destination of the element, reduce the number of substrates, and realize cost reduction and improvement of development efficiency.

  As a selective aspect of the present invention, the element exposed to the outside from the housing may be an optical element. The optical surface (light receiving surface and light emitting surface) of the optical element is exposed to the outside from the housing, and can emit light to the outside or receive light from the outside.

As a selective aspect of the present invention, the optical element may be a light emitting diode, an infrared light receiving element, an optical sensor, or the like.
The light emitting diode indicates the activation state of the apparatus by blinking of the light emitting diode. Representing the activation state by blinking not only repeats lighting and extinguishing alternately, but also indicates the activation state by appropriately combining lighting and extinction, such as being lit or unlit. Say to represent.
The infrared light receiving element acquires a predetermined remote control code signal (for example, a pulse signal) based on the received infrared blinking signal. The apparatus includes means for controlling the apparatus based on the remote control code signal. That is, the liquid crystal display device can be controlled based on an infrared blinking signal emitted from a remote controller or the like.
The optical sensor generates an electrical signal corresponding to the amount of received light, and the apparatus includes means for controlling the apparatus according to the electrical signal generated by the optical sensor. That is, it is possible to perform brightness control of the video displayed on the screen of the liquid crystal display device and other controls according to the brightness of the surroundings of the liquid crystal display device.

  As a selective aspect of the present invention, the substrate may be a multilayer substrate, and the optical element may be a surface mount type element. When the substrate is a multilayer substrate, the mounting effort is increased in the method of mounting through a through hole. Therefore, when the substrate is a multilayer substrate, the optical element is composed of a surface mount type element (for example, a chip LED). With such a configuration, development efficiency is improved, and the height of components mounted on the board is also reduced, which contributes to improvement in freedom of board layout and space saving.

  As a selective aspect of the present invention, the substrate is connected to a data line of the liquid crystal panel via a flexible substrate, and the flexible substrate is connected to the driver driver IC for the data line by COF (Chip On Film). May be installed. Usually, in a liquid crystal display device having a structure that is wide in the width direction and narrow in the height direction, the substrate for driving the data lines is formed long in the width direction and is disposed on at least one of the upper and lower sides of the liquid crystal panel. Therefore, by using this substrate as the mounting destination of the element, the element can be arranged at any position in the width direction of the upper and lower frame portions of the housing. Therefore, the layout flexibility of the element can be improved and the layout can be optimized. Furthermore, by using the second cable as a flexible substrate and mounting a data line driver IC on the flexible substrate, the number of necessary circuits formed on the substrate is reduced, and the elements can be easily laid out.

As a selective aspect of the present invention, the substrate may be arranged below the liquid crystal panel. In general, optical elements, switches, input / output terminals, and the like of a liquid crystal display device are often arranged in a frame portion below the screen of the liquid crystal panel, and the substrate is arranged below the liquid crystal panel. The element of the present invention is also arranged at the same position as the conventional one.

  As a selective aspect of the present invention, the substrate is connected to a gate line of the liquid crystal panel via a flexible substrate, and the flexible substrate is connected to the gate line driver IC by COF (Chip On Film). May be mounted. Usually, in a liquid crystal display device having a structure that is wide in the width direction and narrow in the height direction, the substrate for driving the gate line is formed long in the height direction and is disposed on at least one of the left and right sides of the liquid crystal panel. Therefore, by using this substrate as the mounting destination of the element, the element can be arranged at any position in the height direction of the left and right frame of the housing. Therefore, the layout flexibility of the element can be improved and the substrate layout can be optimized. Furthermore, by using the second cable as a flexible substrate and mounting a driver driver IC for the gate line on the flexible substrate, the number of necessary circuits formed on the substrate is reduced and the elements can be easily laid out.

As alternative aspect of the present invention, the liquid crystal panel is housed in the housing in a state accommodated in the metal casing with a light source of the liquid crystal panel, it is covered except the screen by the metal case, The metal case may be provided with a notch for leading the second cable from the metal case. That is, by leading the second cable through the notch, the length of the second cable can be shortened and the cost can be reduced. In addition, the board can be easily laid out.

  As a selective aspect of the present invention, an external input / output terminal for video signals may be mounted on the substrate. As the element mounted on the substrate, the input terminal can also be arranged, and the request to arrange the input terminal on the front surface can be easily met. In mounting the input terminal on the substrate, the optical element may also be mounted on the substrate.

  As a selective aspect of the present invention, a switch for switching on / off the main power supply of the apparatus may be mounted on the substrate. As an element to be mounted on the substrate, not only an optical element and an external input / output terminal, but also a switch for switching a main power on state may be adopted. Usually, there is no problem with mounting the power switch arranged on the front side of the housing on the substrate. In mounting the switch on the substrate, the optical element and the external input / output terminal may be mounted on the substrate.

As a selective aspect of the present invention, the substrate is a multilayer substrate disposed below the liquid crystal panel, the element is a surface-mounted light emitting diode and an infrared light receiving element, and the light emitting diode is The activation state of the apparatus is indicated by blinking of the light emitting diode, and the apparatus includes means for controlling the apparatus based on an infrared blinking signal received by the infrared light receiving element, and the substrate is connected via a flexible substrate. wherein is connected to the data lines of the liquid crystal panel, wherein the flexible substrate has driver IC of the data line is mounted by COF (Chip on Film), wherein the liquid crystal panel, the with the light source of the liquid crystal panel It is accommodated in the housing in a state of being accommodated in a metal case, and is covered with the metal case except for the screen, and the second cable is connected to the metal case. Serial are notches formed for deriving from the metal case, in the present apparatus may be configured to display images on the screen of the liquid crystal panel based on the broadcast signal input from the tuner. According to this configuration, a liquid crystal television having a configuration corresponding to the configuration of the present invention can be provided.

  The liquid crystal display device described above includes various modes such as being implemented in a state where it is incorporated in another device or being implemented together with another method. The present invention can also be realized as a liquid crystal display system including the liquid crystal display device. The inventions of these liquid crystal display systems also have the effects and effects described above. Of course, the configurations described in claims 2 to 12 are also applicable to the system.

As described above, according to the present invention, it is possible to effectively use the drive substrate as a mounting destination of the element exposed from the housing, reduce the number of substrates, and realize cost reduction and improvement in development efficiency.
According to the second aspect of the present invention, it is possible to reduce the number of substrates on which the optical element can be mounted on the drive substrate, thereby reducing costs and improving development efficiency.
According to the third aspect of the present invention, it is possible to reduce the number of boards while informing the viewer of the activated state, thereby reducing costs and improving development efficiency.
According to the invention of claim 4, it is possible to realize cost reduction and improvement in development efficiency by reducing the number of substrates while enabling control by the infrared remote controller.
According to the fifth aspect of the present invention, it is possible to realize cost reduction and improvement in development efficiency by reducing the number of substrates while enabling control according to ambient brightness.
According to the sixth aspect of the invention, the development efficiency is improved, and the height of the components mounted on the board is also reduced, which contributes to an improvement in the degree of freedom of board layout and space saving.
According to the seventh aspect of the present invention, it is possible to easily meet the desire to place the input terminal on the front surface.
According to the eighth aspect of the present invention, the power switch can be arranged at the same position as the conventional one while realizing cost reduction and layout flexibility improvement, and the power switch layout flexibility is also improved.
According to the invention of claim 9, it becomes easy to lay out the optical element.
According to the tenth aspect of the present invention, the optical element can be disposed at the same position as in the prior art.
According to the invention of claim 11, it becomes easy to lay out the optical element.
According to the twelfth aspect of the present invention, the cost can be reduced by shortening the cable length, and the board can be easily laid out .

Hereinafter, embodiments of the present invention will be described in the following order.
(1) Configuration of the liquid crystal display device:
(2) Board on which each circuit is mounted:
(3) Board layout:
(4) Summary:

(1) Configuration of the liquid crystal display device:
FIG. 1 is a perspective view showing an external appearance of a liquid crystal television according to the present embodiment, FIG. 2 is a block diagram showing an electrical configuration of the liquid crystal television according to the present embodiment, and FIG. 3 is an electrical diagram of a liquid crystal panel and a drive circuit. It is the block diagram which showed the structure.
In FIG. 1, a liquid crystal television 100 stores each component in a casing in which the screen of the liquid crystal panel is exposed from a rectangular window, and the casing is held by a stand so that the screen of the liquid crystal panel 16 is oriented substantially vertically. I support it. HDMI (High-Definition Multimedia Interface) terminal is provided on the right side of the housing, and uncompressed digital audio and video can be input from HDMI-compatible digital home appliances, enabling high-quality video display and audio output It has become.

  A frame-shaped part (hereinafter referred to as a frame part) surrounding the screen of the liquid crystal panel 16 on the front side of the housing has an optical surface (light-receiving surface or A hole for exposing the light emitting surface to the outside is formed. The hole may be a hole that can transmit light, may be a hole that penetrates the housing, or may be fitted with a material that can transmit light in a wavelength region corresponding to the optical element. For example, a substance or a coating film that easily transmits infrared light is provided at a predetermined position of the frame portion, or a hole is formed at that portion.

Further, as shown in FIG. 1, an input terminal 13, an HDMI terminal 11a, and the like are provided in the lower frame portion, and component signals and HDMI signals can be input, and video display and audio output based on these signals can be performed. It has become. Of course, each terminal may be provided on the other side. In addition , a power switch (a tact switch, an electrostatic switch, etc.) for controlling power on / off of the entire liquid crystal television 100 is disposed in the lower frame portion.

2, a liquid crystal television 100 includes a tuner 10, an HDMI receiver 11, a video processing circuit 12, an input terminal 13 for video / audio signals such as component terminals and composite terminals, a drive circuit 14, an audio processing circuit 18, a speaker 20, and a microcomputer. 22, remote control receiver 30 that receives infrared blinking signals received from power supply circuit 24, inverter circuit 26, backlight 28, and remote controller 50 and outputs pulsed voltage signals corresponding to the blinking to microcomputer 22, cursor keys and channels An operation panel 32 that includes a key and outputs a voltage signal corresponding to the key operation to the microcomputer 22 and an LED 34 that displays the start-up state (on / off / standby) of the liquid crystal television 100 when turned on / off.

  The tuner 10 receives a television broadcast signal having a selected frequency. More specifically, the tuner 10 receives a television broadcast signal having a desired frequency via the antenna 10a under the control of the microcomputer 22 and performs a predetermined signal amplification process or the like as an intermediate frequency signal from the television broadcast signal. The video signal and the audio signal are extracted, and the video signal is output to the video processing circuit 12 and the audio signal is output to the audio processing circuit 18. The tuner 10 may be any one of an analog tuner that can receive analog broadcasting, a digital tuner that can receive digital broadcasting, and a tuner that supports both analog and digital.

  The HDMI receiver 11 receives HDMI packetized audio data and video data input via the HDMI terminal 11a, and restores the audio data and video data. The restored audio data and video data are processed under the control of the microcomputer 22 and output to the drive circuit 14 and the audio processing circuit 18.

  The video processing circuit 12 performs various video processes on the video signal extracted from the television broadcast signal. More specifically, the video processing circuit 12 digitizes the input video signal according to the signal level and performs matrix conversion processing based on the luminance signal and the color difference signal extracted from the video signal, RGB (red, green, blue) signals as data are generated. Then, the RGB signal is subjected to scaling processing in accordance with the number of pixels (aspect ratio, m: n) of the liquid crystal panel 16 to generate image data for one screen to be displayed on the liquid crystal panel 16. The image data is output to the drive circuit 14.

  The drive circuit 14 generates drive data for the liquid crystal panel 16 based on the input image data, and displays each image on the screen by driving each display cell of the liquid crystal panel 16 based on the drive data. The liquid crystal panel 16 includes liquid crystal cells arranged in a matrix, scanning lines provided for each row of the arranged liquid crystal cells, data lines provided for each column of the arranged liquid crystal cells, and liquid crystal cells. Correspondingly provided switch elements. The switch element connects the scanning line and the data line. When a voltage is applied to the connected scanning line and the data line, the liquid crystal cell is opened at a rate corresponding to the voltage of the data line.

More specifically, as shown in FIG. 3, the drive circuit 14 includes a timing controller 14a, a source driver 14b, a gate driver 14c, and a gradation circuit 14d. The timing controller 14a generates various timing control signals and outputs the timing control signals to the source driver 14b and the gate driver 14c together with the input image data.
The gate driver 14c drives each gate line of the liquid crystal panel 16 at a timing based on the input timing control signal. The source driver 14b applies a gradation voltage corresponding to the gradation value of the image data input to each pixel to each source line of the liquid crystal panel 16 at a timing based on the timing control signal, so that each source line Drive. The source driver 14b can output a gradation voltage corresponding to each gradation that can be expressed by the liquid crystal panel based on the voltage supplied from the gradation circuit 14d.

The gradation circuit 14d generates a plurality of types of voltage values based on the power supply voltage supplied from the power supply circuit 24 and supplies the generated voltage values to the source driver 14b. The gradation circuit 14d generates, for example, eight voltage values of gradation reference voltages V ₀ , V ₁ , V ₂ , V ₃ , V ₄ , V ₅ , V ₆ , and V ₇ and supplies them to the source driver 14b. To do. The source driver 14b generates a gradation voltage corresponding to the gradation of the input image data by appropriately combining these reference voltages. Of course, the gradation circuit 14d may generate gradation voltages corresponding to all gradations of the image data and supply them to the source driver 14b.

  With the above configuration, in the liquid crystal panel 16, the drive voltage for one horizontal line is input for each horizontal period by the plurality of source drivers 14b of the drive circuit 14, and one horizontal line is input by the plurality of gate drivers 14c. One gate line is sequentially driven every period, and liquid crystal cells for one horizontal line where the source line and the gate line intersect are sequentially driven to perform a display operation.

The audio processing circuit 18 performs various types of audio processing on the audio signal extracted from the television broadcast signal and outputs it to the speaker 20.
The power supply circuit 24 generates various voltages from an AC power supply such as a commercial power supply and supplies the power supply voltage to each part of the liquid crystal television 100. In FIG. 2, only the drive circuit 14 and the inverter circuit 26 are shown as power supply destinations of the power supply circuit 24, but of course, the power supply voltage is also supplied to other circuits.

  The inverter circuit 26 turns on the backlight 28. More specifically, the inverter circuit 26 is supplied with a DC voltage from the power supply circuit 24, generates a high-frequency and high-voltage AC voltage from the DC voltage, and supplies it to the backlight 28. The backlight 28 includes, for example, a plurality of fluorescent tubes (cold cathode fluorescent tubes or the like), lights up with an AC voltage supplied from the inverter circuit 26, and irradiates the liquid crystal panel 16 from the back side. In the present embodiment, description has been made by adopting a fluorescent tube as a light source. However, it goes without saying that an LED may be used, or a reflection type in which external light is reflected and used as a light source may be used. Further, in the present embodiment, the description has been made by adopting the backlight method, but it goes without saying that a front light method or a side light method may be used.

The microcomputer 22 is electrically connected to each part constituting the liquid crystal television 100 and controls the entire liquid crystal television 100. The microcomputer 22 includes a CPU 22a, a RAM 22b, a ROM 22c, and an input / output circuit (I / O) 22d. The CPU 22a reads a program written in the ROM 22c into the RAM 22b as a work area, executes various programs, and performs liquid crystal television. The entire 100 is controlled.
In addition, the microcomputer 22 has, for example, an I / O 22d connected to the remote control receiving unit 30 and the operation panel 32, and an operation input corresponding to the user's remote control operation and an operation input of the operation panel performed by the user are input. The microcomputer 22 executes control processing such as channel selection, volume adjustment, and image quality adjustment based on these operation inputs.

(2) Board on which each circuit is mounted:
The liquid crystal television 100 generally includes a substrate A on which a power supply circuit 24 for performing video / audio signal processing and generation of various power supply voltages and the like, an inverter substrate B on which an inverter circuit 26 is mounted, and driving of the liquid crystal panel 16. And a substrate C (source substrate C1, gate substrate C2, etc.) connected to the line. In the present embodiment, a tuner 10, a video processing circuit 12, an audio processing circuit 18, a microcomputer 22, a power supply circuit 24, and a timing controller 14a are mounted on the substrate A. In the present embodiment, a source driver 14b and a gradation circuit 14d are mounted on the substrate C1, and a gate driver 14c is mounted on the substrate C2.

  FIG. 4 is a schematic cross-sectional view showing the positional relationship among the liquid crystal panel 16, the backlight 28, and the substrates A to C. As shown in the figure, a backlight 28 is disposed on the back side of the liquid crystal panel 16 with a functional light control sheet interposed therebetween, and a box-shaped metal case P covers the back side. The metal case P roughly covers the upper, lower, left and right ends, the upper, lower, left and right side surfaces and the rear surface except the video display area on the front side of the liquid crystal panel 16, and is formed at the lower end of the metal case P as shown in FIG. The flexible substrate connected to the liquid crystal panel 16 through the notch is led out and connected to the source substrate C1. The source substrate C1 is disposed with the surface on which the optical element is mounted facing the inner surface of the front surface of the housing. Substrates A and B are disposed on the back side of the metal case P. In the present embodiment, the liquid crystal panel 16, the backlight 28, the functional light control sheet, and the like are housed in a metal case and can be handled integrally. The present invention is also applicable.

In FIG. 4, the source substrate C1 are is disposed only on the lower side of the liquid crystal panel 16 may be disposed on the upper side of the liquid crystal panel 16 as shown in FIG. 6, both above and below the liquid crystal panel You may arrange. When the source substrate C1 is disposed on both the upper and lower sides of the liquid crystal panel 16, a driving voltage is applied from both upper and lower ends of the data line, and the liquid crystal element to be driven can be driven to a target aperture ratio more reliably. In addition to a certain merit, there is an advantage that the degree of freedom of layout is improved when an optical element or the like is arranged on the source substrate C1 as described later. Although not shown in FIGS. 4 and 5, the gate substrate C2 is also disposed on at least one of the left and right side surfaces of the liquid crystal panel 16, and the source substrate C1 when an optical element is mounted on the gate substrate C2. The same effects as when the optical element is mounted on are provided.

  In this embodiment, the source driver 14b is an IC, and a single IC drives a plurality of source lines of the liquid crystal panel. By providing a plurality of source driver ICs, all the source lines of the liquid crystal panel 16 can be driven. A flexible substrate (film-like interface) may be used for connection between the source substrate C1 and the liquid crystal panel 16, and a source driver IC may be mounted on the flexible substrate by COF (Chip On Film). In addition, a source driver IC can be mounted on the glass substrate of the liquid crystal panel 16 by COG (Chip On Glass). When the source driver IC is mounted by COF or COG, the area of the printed circuit board is reduced, so that effects such as cost reduction and space saving can be expected. This flexible substrate corresponds to the second cable.

  In the present embodiment, a gate driver 14c is mounted on the gate substrate C2. As in the case of the source substrate C1, the gate substrate IC is mounted on the connection line between the gate substrate C2 and the liquid crystal panel 16 by using a flexible substrate with COF or gated on the glass substrate of the liquid crystal panel 16 with COG. A driver IC may be mounted.

  In the present embodiment described below, the case where an optical element is mounted on the source substrate C1 will be described as an example. Of course, similar mounting is possible on the gate substrate C2. The optical elements referred to here are the LED 34, the infrared light receiving element of the remote control receiving unit 30, an optical sensor, and the like, which receive and transmit light (including not only visible light but also infrared light). An element that can be used. For example, the LED 34 disposed on the source substrate C1 emits light from the front surface of the liquid crystal television 100 through a hole formed in the housing, and the infrared light receiving element of the remote control receiver 30 is liquid crystal through the hole formed in the housing. A remote control code signal expressed by infrared rays transmitted toward the front of the television 100 is received.

  The source substrate C1 is arranged with the surface on which the optical element is mounted facing the inner surface of the housing. At this time, the source substrate C1 is disposed so that its mounting surface is substantially parallel to the inner surface of the housing and the display surface of the liquid crystal panel 16. If the substrate surface of the source substrate C1 is disposed so as to be substantially perpendicular to the display surface of the liquid crystal panel 16, an infrared light receiving element is disposed at the front end of the source substrate C1 in consideration of the infrared signal reception efficiency. A device for arranging the light-receiving surface facing forward or bending the LED foot is necessary. On the other hand, with the arrangement of the present embodiment, the optical element may be mounted on any part on the source substrate, and the degree of freedom of circuit element layout on the source substrate C1 is improved.

  Conventionally, the optical element is disposed in the frame portion on the front surface of the casing surrounding the liquid crystal panel 16, and is often disposed in the lower frame or the upper frame portion. The source substrate C1 is also disposed on at least one of the upper and lower frames of the liquid crystal panel 16, and is a substrate that is long in the screen width direction of the liquid crystal panel 16. Therefore, the optical element mounted on the source substrate C1 is more flexible in layout than the conventional method of providing an optical element dedicated substrate.

  Further, when the source substrate C1 is a multilayer substrate, it is preferable that the optical element mounted on the source substrate C1 is a surface-mount type component. This is because surface mount components can be mounted by reflow.

  Power supply to the optical element, control signal input, an output signal from the optical element, and the like are transmitted through a connection cable between the substrate A and the source substrate C1. This connection cable corresponds to the first cable. Conventionally, the substrate A and the source substrate C1 are connected by a cable that supplies image data, a control signal, and a power supply voltage. Since the signals input to and output from the optical element are basically close to direct current, the number of conventional cables and connectors can be changed by using unused cables or changing to cables with more transmission lines. It can respond to mounting of an optical element without.

  Furthermore, sensors may be mounted on the source substrate C1. Sensors, for example, detect the brightness (brightness, illuminance, luminance, luminous intensity, etc.) around the liquid crystal television 100, or detect whether there is a person on the front side of the liquid crystal television 100 with light. It is a sensor. Specifically, an optical sensor, a temperature sensor, an infrared sensor, an ultrasonic sensor, etc. can be considered. Sensors can also be easily mounted on a multi-layer board if they are surface-mounted components. For example, in the case of an optical sensor, the acquired amount of received light is converted into an electrical signal and output to the microcomputer 22. The microcomputer 22 acquires this electrical signal via, for example, the I / O 22d, and controls the video displayed on the screen of the liquid crystal display device according to the brightness of the liquid crystal television 100, brightness control of the video, Other controls can be performed.

  Furthermore, an external input / output terminal may be mounted on the source substrate C1. The external input / output terminal is an input terminal 13 such as a composite terminal or a component terminal, an HDMI terminal 11a, or the like, and includes an output terminal for outputting a video signal or an audio signal to an external device in addition to the input terminal 13 described above. May be. In the case of outputting video and audio, the microcomputer 22 or a dedicated circuit or IC realizes the function of converting into video and audio signals in accordance with the output terminal standard. When an HDMI output terminal is installed, an HDMI transmitter is also required. For the HDMI input terminal or output terminal, a repeater is provided as appropriate according to the transmission distance to the HDMI transmitter or receiver to restore the attenuated transmission signal to support long distance transmission. Further, it is of course possible to mount a main power switch on the source substrate C1.

  As described above, by mounting optical elements, sensors, external input / output terminals, switches, and the like on the source substrate C1, a dedicated substrate, a dedicated connection cable, and mounting and management costs thereof are not necessary. Therefore, not only cost reduction but also design efficiency and manufacturing efficiency are improved.

  By the way, the substrate A may be formed on a single substrate. For example, a circuit for processing a high-frequency signal is mounted on the multilayer substrate A1 to prevent EMI, and a circuit having a low EMI has a single-layer substrate A2. It may be distributed and mounted on a plurality of substrates, as in By distributing the circuit to the single-layer substrate A2 and the multilayer substrate A1 according to the frequency characteristics, it is possible to efficiently realize EMI prevention and cost reduction. This substrate A or substrate A1 corresponds to the main substrate.

  In the present embodiment, the circuits mounted on the single-layer substrate A2 are mainly the power supply circuit 24 and the audio processing circuit 18, and the input terminal 13 for inputting an analog signal such as a component terminal is also mounted. If the input analog video signal is subjected to analog video signal processing and then A / D converted, the analog processing portion of the video processing circuit is also mounted on the single-layer substrate A2.

  The circuits mounted on the multilayer substrate A1 in this embodiment are mainly the video processing circuit 12, the HDMI receiver 11, the timing controller 14a, the LVDS transmitter 14e, the tuner 10 capable of receiving digital broadcasting, the HDMI terminal 11a, and the LVDS connector 14g. is there. The LVDS transmitter 14e converts the image data and timing control signal output from the timing controller 14a into a serial signal and outputs the serial signal to the LVDS connector 14g. The LVDS connector 14g is connected to the LVDS connector 14h mounted on the source board C1 by an LVDS cable, and the serial signal output from the LVDS transmitter 14e is restored by the LVDS receiver 14f on the source board C1.

  Note that the interface for connecting the multilayer substrate A1 and the source substrate C1 is not limited to LVDS, and various interfaces can be adopted as long as the data transfer per unit time is high speed. For example, instead of LVDS, an interface that achieves further low power consumption and low EMI, such as mini-LVDS or V-by-One (R) HS, may be adopted, and by using these, further space saving is possible. Also, low power consumption and low EMI can be realized.

(3) Board layout:
Here, the arrangement of the substrates A1 and A2 shown in FIGS. 5 and 6 will be described. However, this board layout is an example, and the present invention is not limited to this.
FIG. 5 is a schematic diagram showing the substrate arrangement on the back surface and upper side of the metal case P. As shown in the figure, on the back side of the metal case P, the inverter board B is arranged close to one end (in the following description, described as the right end in accordance with FIG. 5), and the other end. (In the following description, it will be described as the left end in accordance with FIG. 5), the multilayer substrate A1 is disposed, and the single layer substrate A2 is disposed in the space between the inverter substrate B and the multilayer substrate A1. The source substrate C1 is disposed above or below the liquid crystal panel 16 (in the following description, it will be described as being above according to FIG. 5), and the multilayer substrate A1 and the single layer substrate A2 are disposed on the source substrate C1. It is arranged close to the end of the side.

  An LVDS connector 14g is mounted on the source substrate C1 in the vicinity of the multilayer substrate A1, and is connected to the LVDS connector 14h of the multilayer substrate with an LVDS cable. A power connector 14i is mounted on a portion of the source substrate C1 adjacent to the single layer substrate A2, and is connected to the power connector 24a of the single layer substrate A2 by a cable. Thus, by providing the power supply connector 14i separately from the LVDS connector 14h in the source substrate C1, it is possible to supply power from the power supply circuit 24 to the source substrate C1 without going through the multilayer substrate A1, thereby reducing the substrate area of the multilayer substrate A1. be able to.

  The HDMI terminal 11a mounted on the multilayer substrate A1 is mounted close to the left end of the substrate, and an HDMI cable can be connected through a hole formed in the housing. By arranging the HDMI terminal at the left end of the multilayer substrate A1, the HDMI cable can be easily inserted and removed from the hole on the left side of the housing.

  When the multilayer board is arranged near the center in accordance with the LVDS cable extending from the vicinity of the center upper end as in the case where the liquid crystal module is optimized alone, when the HDMI port is formed on the left side surface of the housing In order to transmit the HDMI signal to the multilayer board, the transmission distance must be extended with an HDMI cable and a repeater. In the present embodiment, since the HDMI terminal can be arranged on the multilayer substrate A1, it is possible to avoid an increase in cost due to the addition of an HDMI cable or repeater.

Furthermore, since the single-layer substrate A2 and the multilayer substrate A1 are arranged side by side on the left and right, the multilayer substrate A1 is not positioned above the power supply circuit 24, and the video processing circuit 12 and the drive circuit 14 are burned by the heat generated by the power supply circuit 24. There is no worry. In the prior art in which the multilayer substrate A1 is disposed above the single layer substrate A2, when the heat generation of the power supply circuit is large, for example, a control IC that constitutes the video processing circuit of the multilayer substrate A1 and a timing controller that constitutes the drive circuit 14 In order to protect circuit elements that are vulnerable to heat rise, such as the above, it has been necessary to devise such as attaching a heat sink or providing an enclosure so that hot air does not hit the circuit elements. In FIG. 6, the upper side of the liquid crystal panel 16 is adopted as the arrangement location of the source substrate C1. However, as shown in FIG. 5, in order to prevent the heat from the power supply circuit 24 against the multilayer substrate A1. It is preferable to dispose the source substrate C1 below the liquid crystal panel 16.

  Furthermore, since the necessary gradation voltage differs for each type of liquid crystal panel, the versatility of the power supply circuit 24 is lost when the gradation circuit 14d is mounted on the single-layer substrate A2, but the gradation circuit 14d is used as the source substrate C1. When mounted, the versatility of the power supply circuit 24 is improved, and the circuit mounted on the single-layer substrate A2 can be shared without being affected by the type of the liquid crystal panel. That is, it is not necessary to change the design of the single-layer substrate A2 for each type of liquid crystal panel.

  Further, as shown in FIGS. 5 and 6, the portion of the source substrate C1 formed on the printed wiring board may be divided into two and the substrates may be connected by a cable. In this case, the power supply and video data input to one board are transmitted to the other board via the cable. The merit of dividing the source substrate C1 in this way is that the substrate area is minimized and the cost is reduced. That is, since the signal processed by the source substrate C1 is a high frequency, it is generally created by a multilayer substrate. However, the area occupied by the gradation circuit 14d is not so large, and if the source driver 14b is also integrated, the area occupied is small. Furthermore, when the source driver IC is mounted on the film-like interface by COF as described above, the area on which the circuit is formed on the multilayer substrate becomes smaller. In such a case, the total area of the source line multilayer substrate can be reduced by dividing the substrate into two and disposing each source substrate at the approximate center of the source line group that each substrate is responsible for. Of course, as long as it is less than the number of source driver ICs, it may be divided into two or more.

(4) Summary:
As described above, according to the liquid crystal television according to the present embodiment, in the liquid crystal television 100 in which the rear surface of the liquid crystal panel 16 is covered with the metal case P and the front surface of the housing exposes the screen of the liquid crystal panel 16. Provided outside the metal case P, the drive data of the data line of the liquid crystal panel 16 is input from the substrate A through the LVDS cable, and the source substrate C1 connected to the data line through the flexible substrate is provided. C1 is an element that is exposed from the housing (the exception of the liquid crystal panel) are mounted, toward the device is mounted on the inner side surface of the housing front portion not facing the front of the liquid crystal panel 16 A hole for exposing the element to the outside is formed in the front surface of the housing. Therefore, it is possible to provide a liquid crystal television in which the drive substrate is effectively used as a mounting destination of the element that exposes the casing.

Needless to say, the present invention is not limited to the above embodiments. It goes without saying for those skilled in the art,
-Applying the combination of the mutually replaceable members and configurations disclosed in the above-described embodiments as appropriate-The above-described embodiments are not disclosed in the above-described embodiments, but are publicly known techniques. The members and structures that can be mutually replaced with the members and structures disclosed in the above are appropriately replaced, and the combination is changed and applied. It is an embodiment of the present invention that a person skilled in the art appropriately replaces the members and configurations that can be assumed as substitutes for the members and configurations disclosed in the above-described embodiments, and changes the combination to apply. It is disclosed as.

It is a perspective view which shows the external appearance of a liquid crystal television. It is the block diagram which showed the electric constitution of the liquid crystal television. It is the block diagram which showed the electrical structure of the liquid crystal panel and the drive circuit. It is typical sectional drawing which shows positional relationships, such as a board | substrate. It is a schematic diagram which shows the board | substrate arrangement | positioning in the back surface and upper side of a metal case. It is a schematic diagram which shows the board | substrate arrangement | positioning in the back surface and lower side of a metal case. It is a fragmentary perspective view explaining the notch of a metal case.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Tuner, 10a ... Antenna, 11 ... HDMI receiver, 11a ... HDMI terminal, 12 ... Video processing circuit, 13 ... Input terminal, 14 ... Drive circuit, 14a ... Timing controller, 14b ... Source driver, 14c ... Gate driver, 14d ... gradation circuit, 14e ... LVDS transmitter, 14f ... LVDS receiver, 14g ... LVDS connector, 14h ... LVDS connector, 14i ... power connector, 16 ... liquid crystal panel, 18 ... audio processing circuit, 20 ... speaker, 22 ... microcomputer, 22a ... CPU, 22b ... RAM, 22c ... ROM, 22d ... I / O, 24 ... power supply circuit, 24a ... power supply connector, 26 ... inverter circuit, 28 ... backlight, 30 ... remote control receiver, 32 ... operation panel, 34 ... LED, 50 ... remote control, 100 ... liquid crystal television Emissions, A1 ... multilayer substrate, A2 ... monolayer substrate, B ... inverter board, C1 ... source substrate

Claims (12)

In the liquid crystal display device in which the metal case covers the back of the liquid crystal panel and the front of the housing exposes the screen of the liquid crystal panel,
Provided outside the metal case, the drive data of the drive line of the liquid crystal panel is inputted from the main board via the first cable, and the board is connected to the drive line via the second cable. ,
Said substrate, said has element that is exposed is mounted from the housing an element excluding the liquid crystal panel, wherein the portion before Kimoto child does not face the on-board surface to the front surface of the liquid crystal panel It is arranged toward the inner side of the front of the housing,
A liquid crystal display device, wherein a hole for exposing the element to the outside is formed in a front surface of the housing.   The liquid crystal display device according to claim 1, wherein the element is an optical element.   The liquid crystal display device according to claim 2, wherein the optical element is a light emitting diode, and the activation state of the apparatus is displayed by blinking of the light emitting diode. The optical element is an infrared light receiving element,
4. The liquid crystal display device according to claim 2, further comprising means for controlling the device based on an infrared blinking signal received by the infrared light receiving element. The optical element is an optical sensor;
5. The liquid crystal display device according to claim 2, further comprising means for controlling the device in accordance with an amount of light received by the optical sensor. The substrate is a multilayer substrate;
The liquid crystal display device according to claim 2, wherein the optical element is a surface-mount type element. The element is a liquid crystal display device according to any one of claims 1 to 6 which is an external input-output terminal.   The liquid crystal display device according to claim 1, wherein the element is a switch that switches on / off of a main power supply of the apparatus.   The substrate is connected to the data line of the liquid crystal panel via a flexible substrate as the second cable, and the driver driver IC for the data line is mounted on the flexible substrate by a COF (Chip On Film) method. The liquid crystal display device according to any one of claims 1 to 8. The liquid crystal display device according to claim 1, wherein the substrate is disposed below the liquid crystal panel.   The substrate is connected to the gate line of the liquid crystal panel through a flexible substrate as the second cable, and the flexible substrate is mounted with a driver driver IC for the gate line by a COF (Chip On Film) method. The liquid crystal display device according to any one of claims 1 to 10. The liquid crystal panel is housed in the housing in a state accommodated in the metal casing with a light source of the liquid crystal panel, it is covered except the screen by the metal case,
12. The liquid crystal display device according to claim 1, wherein a notch for leading the second cable from the metal case is formed in the metal case.

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