WO2007060781A1 - 表示装置 - Google Patents
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- WO2007060781A1 WO2007060781A1 PCT/JP2006/317334 JP2006317334W WO2007060781A1 WO 2007060781 A1 WO2007060781 A1 WO 2007060781A1 JP 2006317334 W JP2006317334 W JP 2006317334W WO 2007060781 A1 WO2007060781 A1 WO 2007060781A1
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- display device
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- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
- G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
- G09G3/2092—Details of a display terminals using a flat panel, the details relating to the control arrangement of the display terminal and to the interfaces thereto
- G09G3/2096—Details of the interface to the display terminal specific for a flat panel
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- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
- G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
- G09G3/34—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source
- G09G3/36—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source using liquid crystals
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- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
- G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
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- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
- G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
- G02F1/1333—Constructional arrangements; Manufacturing methods
- G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
- G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
- G02F1/1333—Constructional arrangements; Manufacturing methods
- G02F1/1345—Conductors connecting electrodes to cell terminals
- G02F1/13452—Conductors connecting driver circuitry and terminals of panels
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
- G06F3/14—Digital output to display device ; Cooperation and interconnection of the display device with other functional units
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- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
- G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
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- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
- G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
- G09G3/34—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source
- G09G3/3406—Control of illumination source
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- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
- G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
- G02F1/1333—Constructional arrangements; Manufacturing methods
- G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
- G02F1/1336—Illuminating devices
- G02F1/133602—Direct backlight
- G02F1/133612—Electrical details
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- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G2320/00—Control of display operating conditions
- G09G2320/06—Adjustment of display parameters
- G09G2320/0626—Adjustment of display parameters for control of overall brightness
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- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G2360/00—Aspects of the architecture of display systems
- G09G2360/14—Detecting light within display terminals, e.g. using a single or a plurality of photosensors
- G09G2360/145—Detecting light within display terminals, e.g. using a single or a plurality of photosensors the light originating from the display screen
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- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G2370/00—Aspects of data communication
- G09G2370/04—Exchange of auxiliary data, i.e. other than image data, between monitor and graphics controller
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- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G2370/00—Aspects of data communication
- G09G2370/08—Details of image data interface between the display device controller and the data line driver circuit
Definitions
- the present invention relates to a display device, and more particularly to a display device that employs an optical communication system inside the device.
- an active matrix liquid crystal display device having a TFT (Thin Film Transistor) as a switching element is conventionally known.
- This liquid crystal display device includes a liquid crystal panel that also has two insulating substrate (typically glass substrate) forces facing each other.
- a scanning signal line (gate bus line) and a video signal line (source bus line) are provided in a lattice pattern on one substrate of the liquid crystal panel (hereinafter referred to as “TFT substrate”).
- a TFT is provided near the intersection with the signal line.
- the TFT has a gate electrode connected to the scanning signal line, a source electrode connected to the video signal line, and a drain electrode.
- the drain electrode is connected to pixel electrodes arranged in a matrix on the substrate in order to form an image.
- This TFT substrate is integrally provided with a drive circuit for driving the scanning signal lines and the video signal lines, and a display control circuit for generating timing signals for driving these drive circuits. Often formed, or some or all of these circuits are mounted as an integrated circuit chip.
- the video signal applied to the video signal line through this display control circuit is applied to the external force of the apparatus through an FPC (Flexible Printed Circuit) substrate connected to the TFT substrate.
- FPC Flexible Printed Circuit
- the other substrate (hereinafter referred to as "CF substrate") of the liquid crystal panel is provided with an electrode (hereinafter referred to as "common electrode” t,
- Each pixel forming portion is realized by the pixel electrode, the common electrode, and the liquid crystal layer.
- a color filter partially having a color corresponding to the pixel color to be formed by the pixel forming portion is disposed on the CF substrate.
- Such a liquid crystal display device is opposed to a reflective liquid crystal display device that performs display (hereinafter referred to as “reflective display” t) using external light incident from the outside of the device through the CF substrate, and the TFT substrate. It is roughly divided into transmissive liquid crystal display devices that use display (hereinafter referred to as “transmissive display” and ⁇ ⁇ ) that uses the transmitted light of the backlight illuminator power provided at the position opposite to the CF substrate. it can. There is also a transflective liquid crystal display device that mainly performs transmissive display in dark places and mainly performs reflective display in bright places.
- the backlight illuminating device provided in this transmissive (or transflective) liquid crystal display device is a white light emitting diode (LED) or cold cathode fluorescent tube (CCFT) used as a light source.
- LED white light emitting diode
- CCFT cold cathode fluorescent tube
- Fluorescent Tube and a light guide plate that radiates incident light from a light source in a planar shape from a predetermined surface.
- the backlight illumination device (the light source) is also supplied with a predetermined current via the FPC board as a power source external to the device.
- this liquid crystal display device includes an FPC substrate connected to a TFT substrate of a liquid crystal panel and an FPC substrate connected to a knocklight illumination device (light source thereof).
- the FPC board connected to the TFT substrate has a very large number of connection lines (number of terminals, that is, the number of pins).
- number of terminals that is, the number of pins.
- a 2 type liquid crystal panel used in a mobile phone provides video signals. A few pin connections are required.
- the FPC board having such a large number of pins is crimped and connected to the input terminal on the glass board, a vibration occurs when it is mounted on a mopile device after a connection failure occurs or immediately after a good connection.
- the terminal may be peeled off during repair or repair.
- Patent Document 1 Japanese Unexamined Patent Publication No. 2003-149665 Disclosure of the invention
- the number of so-called system liquid crystal panels in which circuits having functions other than video display (for example, an audio output circuit and an excitation source) are integrated on the TFT substrate is increasing.
- the number of pins on the board will increase.
- the number of input terminals that can be formed on the short side of the above-mentioned type 2 small liquid crystal panel is about 60 pins.
- the number of audio input terminals required when providing an audio circuit on a TFT substrate is about 20 pins. Therefore, since the number of terminals required for video signal input is less than 40 pins, it is difficult to connect the TFT substrate to the FPC substrate, and it is impossible to connect when routing the wiring. Is also possible. In such a case, the FPC board is not particularly suitable as a signal transmission unit.
- an object of the present invention is a signal transmission mechanism that can reduce the number of pins of an FPC board connected to a TFT substrate or can eliminate the need for the FPC board.
- a display device including a signal transmission mechanism that can be easily applied to a display. Means for solving the problem
- a first aspect of the present invention is an active matrix comprising a plurality of pixel forming portions arranged in a matrix corresponding to intersections of a plurality of video signal lines and a plurality of scanning signal lines, respectively.
- Type display device
- a first unit provided with the plurality of pixel forming portions and a predetermined circuit
- a second unit that is fixed at a position facing the first unit and receives a signal to be supplied to a circuit included in the first unit from an external device;
- the second unit includes an optical transmitter for optically transmitting a signal to be given to the circuit to the first unit;
- the first unit includes an optical receiver that receives a signal optically transmitted by the optical transmitter and applies the signal to the circuit.
- a second aspect of the present invention is the first aspect
- the optical transmitter is a first optical transmitter.
- a backlight source that emits illumination light for display on a surface opposite to the display surface in the first unit
- a drive unit for driving the backlight light source based on a signal to be supplied to the circuit.
- a third aspect of the present invention is the second aspect of the present invention.
- the drive unit performs conversion for baseband transmission on a signal to be supplied to the circuit, and drives the backlight light source by the converted signal.
- a fourth aspect of the present invention is the second aspect of the present invention.
- the drive unit performs predetermined modulation for band transmission using a signal to be supplied to the circuit as a modulation signal, and drives the backlight light source by the modulated signal.
- the backlight light source is a planar light emitter that emits illumination light over substantially the entire surface of the first unit opposite to the display surface;
- the light receiving unit receives illumination light having the backlight light source power.
- a sixth aspect of the present invention is the second aspect of the present invention, in which
- the light transmission unit includes a light guide that guides the illumination light of the backlight light source power so as to irradiate almost the entire surface of the first unit opposite to the display surface, and the light reception unit includes: The illumination light passing through the light guide is received.
- the backlight light source includes a light emitting diode.
- An eighth aspect of the present invention is the seventh aspect of the present invention.
- the backlight source includes only a light emitting diode that emits white light.
- a ninth aspect of the present invention is the seventh aspect of the present invention.
- the backlight light source includes a plurality of light emitting diodes.
- a tenth aspect of the present invention is the ninth aspect of the present invention.
- the driving unit separates a signal to be supplied to the circuit into a plurality of signals for performing multilink between the plurality of light emitting diodes and the optical receiving unit, and the plurality of light emission based on the plurality of signals.
- the driving unit separates a signal to be supplied to the circuit into a plurality of signals for performing multilink between the plurality of light emitting diodes and the optical receiving unit, and the plurality of light emission based on the plurality of signals.
- the optical receiver is
- a plurality of light receiving elements uniquely corresponding to the plurality of light emitting diodes
- An eleventh aspect of the present invention is the ninth aspect of the present invention.
- the driving unit separates a signal to be supplied to the circuit into a plurality of separated signals that define the transmission period and the non-transmission period so that transmission periods for transmitting the signals do not overlap each other in the optical receiving unit. And driving the plurality of light emitting diodes based on the separation signal,
- the optical receiver is
- One light receiving element for receiving light from the plurality of light emitting diodes
- a restoration unit for restoring a signal to be given to the circuit from a signal received by each of the light receiving elements
- a twelfth aspect of the present invention is the eleventh aspect of the present invention.
- the plurality of light emitting diodes are arranged at a predetermined interval from each other, and the driving unit transmits a signal to be supplied to the circuit, and a transmission period for transmitting the signal is in the optical receiving unit, Each of them is separated into a plurality of separated signals having the same transmission period and non-transmission period, and the plurality of light emitting diodes are driven based on the separated signals.
- the light receiving element receives light from the plurality of light emitting diodes with a time difference corresponding to a distance from an arrangement position of each light emitting diode.
- a thirteenth aspect of the present invention is the ninth aspect of the present invention.
- the plurality of light emitting diodes include a plurality of light emitting diodes that emit light of different colors.
- a fourteenth aspect of the present invention is the thirteenth aspect of the present invention.
- the driving unit drives only a light emitting diode emitting a color having the highest light receiving sensitivity in the light receiving unit among the plurality of light emitting diodes emitting different colors based on a signal to be given to the circuit. To do.
- a color filter that transmits only light emitted from the corresponding light emitting diode is further provided on each optical path from the plurality of light emitting diodes to the light receiving unit.
- a chassis provided between the first unit and the second unit to support the first unit or the second unit;
- the chassis is provided with a through hole that forms an optical path from the optical transmitter to the optical receiver.
- the driving unit drives the backlight light source based on a signal to be given to the circuit only during a period when the backlight light source is lit.
- the optical receiver may receive a signal that is optically transmitted only while the backlight light source is on.
- An eighteenth aspect of the present invention is the seventeenth aspect of the present invention.
- the optical reception unit includes a detection unit that detects light from the optical transmission unit, and receives an optically transmitted signal only during a period in which light is detected by the detection unit.
- a nineteenth aspect of the present invention is the seventeenth aspect of the present invention.
- the drive unit repeatedly turns on and off at a predetermined rate at a predetermined short time interval. And driving the backlight light source based on a signal including a signal indicating the ratio and a signal to be given to the circuit.
- the optical receiver receives a signal that is optically transmitted only during a period in which the backlight light source is lit based on the ratio indicated in the received signal.
- the driving unit drives the backlight light source so as to repeat lighting and extinguishing at a predetermined rate at a predetermined short time interval, and outputs a signal indicating the rate and a signal to be given to the circuit. Based on, driving the backlight source,
- the optical receiver adjusts at least one of the light receiving sensitivity and the amplification factor based on the ratio indicated in the received signal so that a signal to be given to the circuit can be satisfactorily received.
- the circuit includes a circuit for driving the plurality of video signal lines and the plurality of scanning signal lines, respectively.
- the optical transmission unit optically transmits a video signal to be supplied to the circuit to the first unit.
- the circuit includes an audio output circuit that outputs audio based on a given signal, and the optical transmission unit optically transmits an audio signal to be supplied to the circuit to the first unit.
- the optical transmitter includes a light emitting element for optical transmission
- the light receiving unit includes a light receiving element corresponding to the light emitting element,
- the light receiving element is formed on the first unit integrally with the circuit.
- a twenty-fourth aspect of the present invention is the twenty-third aspect of the present invention.
- the light emitting element is a laser light source.
- a twenty-fifth aspect of the present invention is the twenty-third aspect of the present invention,
- the light emitting element is a fluorescent tube light source.
- a twenty-sixth aspect of the present invention is the first aspect of the present invention, in which
- the second unit includes a second coil through which an alternating current received from the device external force flows,
- the first unit includes a first coil in which a current is excited by mutual induction with the second coil;
- the first coil supplies the excited current to the circuit as a power source.
- the first unit includes a solar cell
- the solar cell is characterized in that a current generated by receiving light from the light transmitter or predetermined illumination light is supplied to the circuit as a power source.
- the signal applied to the second unit external force to the optical receiving unit of the first unit in which the plurality of pixel forming units and the predetermined circuit are provided.
- the transmission medium for applying the external force signal to the first unit typically the FPC board, can be omitted or the number of pins can be increased. Regardless, it can be increased.
- the signal to be transmitted is transmitted using the backlight source that emits illumination light, it is not necessary to newly provide a light emitting element for light transmission. Since the driving circuit for illumination can also be used for generating an optical signal, the manufacturing cost can be reduced.
- the backlight light source is driven by a signal that has undergone conversion for baseband transmission, the configuration for conversion can be simplified. Further, when transmitting a digital signal composed of a pulse train, it is possible to reduce the occurrence of flickering force. Furthermore, when the knocklight light source is subject to dimming control using pulses such as PWM, it is possible to perform baseband transmission using that noise, so efficient light transmission is possible. It becomes possible.
- the backlight source is driven by a signal subjected to modulation for band transmission, so that the modulated signal can be easily separated in the optical receiver, and transmission errors are reduced. can do.
- the knock light source is a planar light emitter such as an EL backlight
- uniform illumination light can be obtained with a simple configuration, and the position of the light receiving unit can be determined. It can be set freely, and it is not necessary to form the optical path, for example, by providing a through hole.
- the position of the light receiving unit can be set more freely than the configuration in which light is directly received from the light transmitting unit.
- the knock light source includes a light emitting diode
- a backlight light source with high brightness and low power consumption can be obtained, and lighting and non-lighting can be repeated at high speed. Therefore, a large amount of information can be optically transmitted.
- the knock light source includes only a light emitting diode that emits white light, white light that is a general backlight illumination color can be easily obtained.
- the backlight source since the backlight source includes a plurality of light emitting diodes, it is possible to obtain illumination light stronger than in the case of one.
- the plurality of light emitting diodes are driven based on the plurality of signals separated in order to perform multilink by the driving unit, and are received by the optical reception unit. Since the signal to be applied to the circuit is restored from the signal that is generated, the light emitting diode is driven by such a multi-link method even when the frequency of the signal to be applied to the circuit exceeds the maximum driveable frequency of the light emitting diode. As a result, a large amount of information can be optically transmitted.
- a plurality of light emitting diodes are driven based on the signal, and the light receiving unit receives light from the plurality of light emitting diodes. Therefore, signal transmission can be realized with a simple configuration in which only one light receiving element is provided. Also, with this configuration, the light emitting diode is not used during the non-modulation period. Since no signal transmission is performed by the diode, the load on one light emitting diode can be reduced, and as a result, the light emitting life can be extended.
- the optical transmitter drives the plurality of light emitting diodes based on the plurality of separated signals that define the same transmission period and non-transmission period so as not to overlap each other by the driving unit.
- the light receiving unit receives light from a plurality of light emitting diodes with a time difference corresponding to the distance from the position of each light emitting diode, only one light receiving element is provided, and the same transmission period and Signal transmission can be realized with a simple configuration based on a signal having a non-transmission period.
- this configuration can reduce the load on one light-emitting diode, and as a result, the light-emitting life can be extended.
- the color of the illumination light is appropriately selected by appropriately switching the light emitting diodes that emit light. It becomes possible to do.
- the photosensitivity can be made higher than, for example, white.
- the color filter is further provided on each optical path from the light emitting diode to the optical receiver, only the necessary optical signal is given to the optical receiver with a simple configuration. be able to.
- the chassis is provided with a through hole that forms an optical path to the optical receiver, and the optical transmitter force, so a path for optical transmission with a simple configuration is provided. Can be secured.
- the optical receiver receives a signal that is optically transmitted only during a period in which the backlight light source is lit. There is no. As a result, it is possible to prevent an erroneous signal from being output during a period when the lamp is not lit.
- an optical signal is received only during a period in which light is detected by the detector, so that an erroneous signal is output during a period when the light is not lit with a simple configuration. Can be prevented.
- the receiver since the signal indicating the ratio between the lighting period and the extinguishing period of the backlight light source is transmitted to the optical transmitter power receiver, the receiver is connected to the backlight light source.
- the receiver By referring to the above ratio without detecting whether the power is on or not, it is possible to reliably receive an optically transmitted signal only when the backlight source is on.
- the twentieth aspect of the present invention since at least one of the light receiving sensitivity and the amplification factor is adjusted based on the ratio between the lighting period and the extinguishing period of the backlight light source, it should be given to the circuit with a simple configuration. Suitable adjustments can be made to ensure that the signal is received well.
- a transmission medium typically an FPC board, is provided for providing a video signal from the outside of the apparatus to the first unit. It can be omitted or it can be done without increasing its pin count.
- the number of pins of the transmission medium, typically the FPC board, for supplying the external unit audio signal to the first unit can be prevented from increasing despite its increased voice function.
- the light receiving element is integrally formed on the first unit, it can be manufactured easily and inexpensively, and particularly when it is formed in a thin film. Since sensitivity to white light is increased, illumination light can be preferably used.
- the twenty-fourth aspect of the present invention by using a laser light source, it is possible to perform light transmission at a higher speed (higher density) than when using a light emitting diode.
- the cost can be reduced by using a fluorescent tube light source, and a simple configuration can be achieved by using, for example, an inverter.
- a medium for applying a device external force power supply to the first unit by applying a current excited in the first coil as a power supply to the circuit can be omitted.
- the device external power source can be applied to the first unit with a simple configuration.
- the medium typically the FPC board, can be omitted.
- FIG. 1 is a perspective view for explaining a partial structure of a liquid crystal display device according to a first embodiment of the present invention.
- FIG. 2 is a plan view for briefly explaining the configuration of the backlight unit in the embodiment.
- FIG. 3 is a diagram for simply explaining the configuration of a liquid crystal module including a backlight unit and a liquid crystal panel in the embodiment.
- FIG. 4 is a diagram for explaining a positional relationship between a light receiving element and a white LED in the embodiment.
- FIG. 5 is a cross-sectional view schematically showing the structure of the light receiving element in the embodiment.
- FIG. 6 in the above embodiment is a diagram showing current values measured when the light receiving element 90 is irradiated with light of different wavelengths.
- FIG. 7 is a block diagram showing a circuit configuration of the liquid crystal display device in the embodiment.
- FIG. 8 is a block diagram showing a detailed configuration of an LED drive circuit in the embodiment.
- FIG. 9 is a waveform diagram schematically showing a modulated signal that has been modulated by the digital modulation method of the band transmission method in the embodiment.
- FIG. 10 is a waveform diagram schematically showing a modulated signal that has been modulated by a digital modulation scheme of a baseband transmission scheme in the embodiment.
- FIG. 11 is a block diagram showing a detailed configuration of a receiving circuit in the embodiment.
- FIG. 12 is a block diagram showing a detailed configuration of an LED drive circuit according to a second embodiment of the present invention.
- FIG. 13 is a simplified waveform diagram of an optical signal LS subjected to dimming control in the embodiment.
- FIG. 14 is a block diagram showing a detailed configuration of a receiving circuit in the embodiment.
- FIG. 15 is a block diagram showing a configuration of a liquid crystal display device according to a third embodiment of the present invention.
- FIG. 16 is a block diagram showing a circuit configuration of an audio output circuit in the embodiment.
- FIG. 17 illustrates the positional relationship between the light receiving element and the white LED in the fourth embodiment of the present invention. It is a figure for doing.
- FIG. 18 is a waveform diagram schematically showing a light signal from a white LED just before being received by the light receiving element in the embodiment.
- FIG. 19 is a plan view showing an FPC for power supply in a modification of each of the above embodiments.
- FIG. 20 is a plan view for explaining an example in which power is supplied by a coil instead of the FPC for power supply in the modified example.
- FIG. 21 is a plan view for explaining an example in which power is supplied by a pin formed on a TFT substrate instead of the power supply FPC in the modified example.
- FIG. 22 is a simplified perspective view for explaining the configuration of a liquid crystal module that can be freely inserted into and removed from the external device housing in the modified example.
- FIG. 1 is a perspective view for explaining a partial structure of the liquid crystal display device according to the first embodiment of the present invention.
- This liquid crystal display device is a transmissive (or transflective) liquid crystal display device and has almost the same configuration as the conventional one, but unlike the conventional configuration, it does not include an FPC board for transmitting video signals, and is a new one. Are provided with a light receiving element and a receiving circuit to be described later for signal transmission.
- this liquid crystal display device includes a liquid crystal panel (liquid crystal display unit) including a CF substrate 10 similar to the conventional one and a TFT substrate 20 different from the conventional one on which a light receiving element and a receiving circuit are formed. 2 and a backlight unit (backlight unit) 3 including white LEDs 40a to 40c serving as a backlight light source for transmissive display and an optical member 30 such as a light guide plate.
- the white LEDs 40a to 40c included in the backlight unit 3 include signals (modulated signals) modulated by a predetermined modulation method via the signal source power FPC board (and the LED driving circuit) outside the apparatus. Current is applied.
- the LED is a light-emitting element with high luminance and low power consumption, and can be repeatedly turned on and off at high speed, and thus is suitable as the light-emitting element of this embodiment. Details will be described later.
- a polarizing sheet is affixed to at least one surface of the liquid crystal panel 2, and a lens sheet or the like is disposed on the light exit surface of the light guide plate that is a light guide included in the knock light unit 3.
- a light diffusion sheet or the like is affixed, and a reflection sheet is affixed to the opposite surface.
- the knock light unit 3 functions as a planar illumination device that provides backlight illumination for liquid crystal display.
- three white LEDs 40a-40c are provided.
- the number is not particularly limited.
- FIG. 2 is a plan view for briefly explaining the configuration of the knock light unit 3.
- the lower bezel portion 60 shown in the upper left side of FIG. 2 has a tray shape, and fixes the optical member 30 such as a light guide plate and the FPC board 50 mounted with the white LEDs 40a to 40c in a predetermined positional relationship. It is stored to be.
- An FPC input terminal 59 for receiving a current for driving the white LEDs 40a to 40c is formed at one end of the FPC board 50.
- An upper side of the lower bezel portion 60 that is, the light emitting surface side facing the liquid crystal panel 2, is fixed so as to cover the resin chassis 70 having the through holes 71a to 71c shown on the upper right side of FIG.
- the backlight unit 3 shown in the lower part of FIG. 2 is produced.
- the positions of the through holes 71a to 7lc in the resin chassis 70 uniquely correspond to the positions of the white LEDs 40a to 40c of the backlight unit 3. . Therefore, the light emitted from the white LEDs 40a to 40c is emitted upward (liquid crystal panel 2 side) through the light guide plate and the like, and the liquid crystal panel 2 passes through the corresponding through holes 71a to 71c. It is given to the light receiving element described later.
- the backlight unit 3 manufactured as described above is disposed below the liquid crystal panel 2, that is, on the side opposite to the display surface.
- FIG. 3 is a diagram for simply explaining the configuration of the liquid crystal module including the backlight unit and the liquid crystal panel.
- the knock light section 3 is arranged at the bottom of the liquid crystal panel 2 and is fixed so as to cover the upper bezel 80 from the upper side (display surface side) of the liquid crystal panel 2 as shown in FIG.
- the liquid crystal module 4 shown at the bottom is produced.
- a light-blocking black matrix 11 is formed on the display surface side of the liquid crystal panel 2 (the CF substrate 10 in the liquid crystal panel 2). This black matrix 11 prevents light from the knock light section 3 from leaking power other than the display surface, and prevents the circuit formed on the TFT substrate 20 from being affected by external light. Since the structure of the black matrix 11 is well known, detailed description thereof is omitted.
- FIG. 4 is a diagram for explaining the positional relationship between the light receiving element and the white LED.
- light receiving elements 90a to 90c are formed on the back surface of the liquid crystal panel 2, that is, the surface opposite to the display surface, with a predetermined interval.
- the sub-elements 90a to 90c are PIN type photodiodes formed on the glass substrate of the TFT substrate 20 by a manufacturing process similar to the TFT manufacturing process, and according to the intensity by receiving light from the white LEDs 40a to 40c. Output the amount of current. This structure will be described later.
- the black matrix 11 is formed on the surface of the liquid crystal panel 2, that is, on the display surface side.
- the light receiving elements 90a to 90c formed on the back surface of the liquid crystal panel 2 are fixed at positions uniquely corresponding to the white LEDs 40a to 40c arranged in the backlight unit 3, respectively. Is done. For example, light emitted from the white LED 40c is given to the light receiving element 90c through the through hole 71c.
- a partition wall or a light guide unit that shields light between the white LEDs 40a to 40c may be provided so that the light of the white LEDs 40a to 40c passes through only one of the corresponding through holes 71a to 71c.
- a partition wall or an enclosure that shields unnecessary light such as external light from entering the light receiving elements 90a to 90c may be provided around the through holes 71a to 71c.
- the through holes 71a to 71c may be filled with glass or the like, and a light guide unit is provided in which a plurality of materials having different refractive indexes are arranged so as to have a structure similar to the cross-sectional structure of the optical fiber. May be.
- the light receiving elements 90a to 90c hereinafter referred to as “light receiving element 90” when they are not distinguished from each other will be described with reference to FIG. 5 and FIG.
- FIG. 5 is a cross-sectional view schematically showing the structure of the light receiving element 90.
- the light receiving element 90 includes a semiconductor layer 91 formed on the glass substrate 21 included in the TFT substrate 20 and a gate insulating film 22 formed so as to cover the semiconductor layer 91. And an interlayer insulating film 23 formed thereon, and an electrode 92 electrically connected to a part of the semiconductor layer 91 through a contact hole opened so as to penetrate these insulating films .
- the description of the flat film was omitted.
- the P region 9la and the N region 91c in the semiconductor layer 91 are doped with a predetermined impurity and the i region 91b is not doped with an impurity, a glass substrate is formed as shown in FIG.
- a PIN junction is formed in a direction along the surface of the plate 21.
- the light receiving element 90 having such a structure is well known and is referred to as a lateral (lateral) structure PIN type photodiode. Since the light receiving element 90 having such a structure can be formed by the same process as the TFT, it can be manufactured at low cost.
- the silicon used for the semiconductor layer may be non-crystalline silicon, but is preferably polycrystalline silicon in order to improve circuit integration, and further has high electron mobility.
- CG continuous grain
- FIG. 6 is a diagram showing current values measured when the light receiving element 90 is irradiated with light of different wavelengths.
- the light receiving element 90 used for the measurement has a gate length L of 7 [m] and a gate width of 5000 [m].
- this light receiving element 90 has a relatively high sensitivity with respect to white light as the output current force decreases (ie, the sensitivity decreases) as the wavelength of light increases.
- a general (non-thin film) photodiode element often has a large output current mainly in the infrared region, so that the sensitivity to white light is low. Many. Therefore, this light receiving element 90 is suitable for the optical transmission system in the present invention using white light.
- FIG. 7 is a block diagram showing a circuit configuration of the liquid crystal display device according to the first embodiment of the present invention.
- This liquid crystal display device includes a light receiving element 90, a receiving circuit 100, a display control circuit 200, a video signal line driving circuit 300, a scanning signal line driving circuit 400, and a display unit 500 formed on the TFT substrate 20 of the liquid crystal panel 2.
- white LED 40a to 40c hereinafter referred to as “white LED 40” t in this case, which are not distinguished from each other included in the knock light unit 3 and an LED drive circuit 51.
- the video signal VS including the above and the like is also supplied from the input terminal 59 of the FPC board 50 to the LED driving circuit 51 formed inside the FPC board 50 or mounted on the FPC board 50 as an integrated circuit.
- the LED drive circuit 51 drives the white LED 40 that outputs (emits) a light (modulation) signal LS corresponding to the video signal VS.
- the detailed configuration of the LED drive circuit 51 will be described later.
- the LED drive circuit 51 does not necessarily have to be mounted on the FPC board 50.
- the receiving circuit 100 and other circuits may be in any form such as being mounted on the TFT substrate 20 as an integrated circuit that does not necessarily have to be integrally formed on the TFT substrate 20. ⁇ .
- the light receiving element 90 included in the TFT substrate 20 converts the optical signal LS received from the white LED 40 included in the knock light unit 3 into an electric signal and supplies the electric signal to the receiving circuit 100.
- the receiving circuit 100 generates (demodulates) the video signal VS from the received electrical signal and supplies it to the display control circuit 200.
- the display control circuit 200 based on the video signal VS received from the receiving circuit 100, includes a source clock signal SCK and a source start pulse signal SSP that are given to the video signal line drive circuit 300 for display on the liquid crystal panel.
- Various signals including a gate clock signal GCK and a gate start pulse signal GSP given to the scanning signal line drive circuit 400 for display are generated. These signals are well known and will not be described in detail.
- the display control circuit 200 supplies the digital image signal Da to the video signal line driving circuit 300 based on the video signal VS.
- the video signal line drive circuit 300 is supplied with the data representing the image to be displayed on the display unit 500 as the digital image signal Da in pixel units, and also as a signal indicating the timing.
- Clock signal SCK for source and start pulse signal SSP for source are supplied.
- the video signal line driving circuit 300 is based on the digital image signal Da, the source clock signal SCK, the source start pulse signal SSP, etc., and the driving video signal SI, which is an analog voltage for driving the display unit 500, S2, S3,..., Sn (n is the number of video signal lines) are generated and applied to each video signal line of the display unit 500.
- the drive video signals SI, S2, S3,..., Sn are inverted in accordance with a polarity switching control signal (not shown) for AC drive of the display unit 500.
- the scanning signal line drive circuit 400 selects each scanning signal line in the display unit 500 in order for each horizontal scanning period in order based on the gate clock signal GCK and the gate start pulse signal GSP. Scanning signals Gl, G2, G3, ..., Gm (m is the number of scanning signal lines) to be applied to each scanning signal, and each scanning signal of the active scanning signal for sequentially selecting each of the scanning signal lines The application to the line is repeated with one vertical scanning period as the cycle.
- Display unit 500 includes a plurality of scanning signal lines (row electrodes) each corresponding to a horizontal scanning line in an image represented by a video signal, and a plurality of intersections with each of the plurality of scanning signal lines.
- a plurality of video signal lines (column electrodes) and a plurality of pixel formation portions provided corresponding to the intersections of the plurality of scanning signal lines and the plurality of video signal lines.
- Each pixel forming section includes a TFT 501 having a source terminal connected to a video signal line passing through a corresponding intersection and a gate terminal connected to a scanning signal line passing through the corresponding intersection, and the TFT 501
- a pixel electrode connected to the drain terminal of the pixel, a common electrode (also referred to as a “counter electrode”) Ec commonly provided in the plurality of pixel formation portions, and a common electrode provided in the plurality of pixel formation portions.
- a pixel capacitor Cp is formed by the pixel electrode Ep, the common electrode Ec, and the liquid crystal layer sandwiched between them.
- the TFT substrate 20 includes the signal lines, TFTs, and pixel electrodes.
- the CF substrate 10 includes the common electrode Ec, a color filter (not shown), various optical compensation films, and the like.
- the display unit 500 when the scanning signal Gk (k is a natural number from 1 to m) applied to the shifted scanning signal line Lg becomes active, the scanning signal line Is selected, the TFT 501 of each pixel formation portion connected to the scanning signal line becomes conductive, and the driving video signal Sj (j is a natural number from 1 to n) is applied to the pixel electrode connected to the TFT 501. Is applied via the video signal line.
- the voltage of the applied driving video signal example (voltage based on the potential of the common electrode Ec) 1S is written as a pixel value in the pixel formation portion including the pixel electrode.
- the display unit 500 displays an image represented by the video signal VS.
- a detailed circuit configuration of the LED drive circuit 51 will be described with reference to FIG.
- FIG. 8 is a block diagram showing a detailed configuration of the LED drive circuit 51. As shown in FIG. As shown in FIG. 8, the LED drive circuit 51 receives the video signal VS and the power control signal PS for controlling the operation of the LED drive circuit 51 from the outside of the liquid crystal display device and receives them.
- Multiplexer 511 for multiplexing separation unit 512 for separating the multiplexed signal into three signals by a well-known multilink method, and a modulated signal obtained by modulating a predetermined signal based on the corresponding signal received from separation unit 512
- modulation units 515a to 515c that output a drive current including a modulated signal for driving white LEDs 40a to 40c
- a current source 514 that supplies current for driving white LEDs 40a to 40c to modulation units 515a to 515c
- the adjustment unit 516 that adjusts the output current of the current source 514 based on the drive current of the white LEDs 40a to 40c by the modulation units 515a to 515c, and the operation of the current source 514 is stopped or started based on the power control signal PS.
- a backlight power supply control unit 513 for controlling that.
- the video signal VS and the power control signal PS are different from the force applied to the multiplexer 511 from the outside of the apparatus via the input terminal 59 of the FPC board 50 as described above.
- the input terminal force may be given or may be given without going through the FPC board 50.
- the multiplexer 511 has the ability to multiplex the received video signal VS and the power control signal PS. Since these signals are digital signals, the signals multiplexed by a known digital multiplexing method are also digital signals. is there.
- the power control signal PS is converted into an optical signal and transmitted to the receiving circuit 100 included in the TFT substrate 20 as will be described later. However, the power control signal PS is not transmitted when the power control for the TFT substrate 20 is unnecessary. It may be a configuration. In this case, the multiplexer 511 is omitted.
- This power control signal PS is given not only to the multiplexer 511 but also to the backlight power supply control unit 513.
- This power control signal PS is a control signal from the outside of the device, and is active when the device is operating, and becomes inactive when the device is stopped.
- the knock light power supply control unit 513 performs control to stop the operation of the current source 514 when the power control signal PS becomes inactive and to start the operation of the current source 514 when it becomes active.
- the backlight power supply control unit 513 simultaneously stops or starts circuits other than the current source 514 included in the LED drive circuit 51. Control is preferably performed. Since the power control signal PS is converted into an optical signal and transmitted, it is preferable that the knock light power control unit 513 performs the stop operation after the transmission operation is completed.
- the separation unit 512 is a digital signal multiplexed by a multiplexer 511 as information to be transmitted with respect to three optical transmission paths formed between the white LEDs 40a to 40c and the light receiving elements 90a to 90c.
- the multiplexed signal is divided into three so that the signals are transmitted separately. In this way, the transmission of information to be transmitted separately to a plurality of physical transmission paths is called multilink.
- the demultiplexing unit 512 that demultiplexes signals to perform the multilink specifically divides the multiplexed digital signal into three for every predetermined amount along, for example, a time series, and divides the frequency by 1Z3.
- the frequency is lowered by dividing by (for example, the pulse period is lengthened) and given to the modulators 515a to 515c.
- the white LEDs 40a to 40c can be driven by the formula.
- Modulation units 515 & 515 digitally modulate a carrier wave of a predetermined frequency obtained by a local oscillator power (not shown) based on the signal received from separation unit 512.
- the frequency is preferably at least a frequency that is invisible or difficult to detect.
- Such digital modulation systems include various band transmission systems such as ASK (Amplitude Shift Keying), FSK (Frequency Shift Keying), and PSK (Phase Shift Keying), and various types such as RZ (Return to Zero). There are baseband transmission systems, and any of them can be used here.
- the modulation in the modulation units 515a to 515c includes a wide range of signal conversion and code conversion in the baseband transmission system in addition to modulation in the band transmission system. Furthermore, it is also possible to adopt various well-known multiple access methods such as CDMA (Code Division Multiple Access) using these.
- CDMA Code Division Multiple Access
- the modulation units 515a to 515c may be omitted, and the three separated signals from the separation unit 512 may be provided to the white LEDs 40a to 40c as they are or via an amplifier, respectively.
- Various known analog modulation schemes may be employed. Next, Figure 9 and A few of these modulation schemes will be described with reference to FIG.
- FIG. 9 is a waveform diagram simply showing a modulated signal that has been modulated by the digital modulation method of the band transmission method.
- the numbers attached below each signal indicate the information content of the digital signal that is the modulation signal.
- the waveform diagram shown in the upper part of Fig. 9 shows a binary ASK modulated signal.
- This binary ASK is a modulation method in which 1-bit information (“1” or “0”) in a digital signal is associated with two types of amplitude (or presence / absence of a carrier) in a carrier wave.
- the waveform diagram shown in the lower part of Fig. 9 shows a 4-level ASK modulated signal.
- This quaternary ASK is a modulation method that associates 2-bit information in a digital signal with four types of amplitude in a carrier wave. Note that these band transmission systems can easily separate modulated signals on the receiving side, and can reduce transmission errors.
- FIG. 10 is a waveform diagram schematically showing a modulated signal that has been modulated by the digital modulation scheme of the baseband transmission scheme.
- the numbers attached below each signal indicate the information content of the digital signal that is the modulation signal.
- the waveform diagram shown in the upper part of Fig. 10 shows an RZ-mode modulated signal.
- This RZ is a transmission system that returns to 0 potential because the pulse width is shorter than the code transmission interval.
- the waveform diagram shown in the middle part of Fig. 10 shows a modulated signal in the PPM (Pulse Position Modulation) method.
- This PPM is a modulation method that associates information (2 bits in the figure) in the digital signal with the positions of the pulses (here, 4 types) in the carrier wave.
- the waveform diagram shown in the lower part of Fig. 10 shows a CDMA modulated signal.
- This CDMA is a modulation method in which information (1 bit in the figure) in a digital signal is associated with a code having a unique pulse sequence. Note that the waveform diagrams shown in FIGS. 9 and 10 are simplified for explanation, and are different from the waveforms of the actual signals output from the modulation units 515a to 515c.
- a code other than the unique code can be regarded as noise. Therefore, on the receiving side, only a desired modulated signal is determined based on the unique code.
- a CDMA optical signal when a CDMA optical signal is used, a configuration that is devised so that light from the white LEDs 40a to 40c is incident only on the corresponding light receiving elements 90a to 90c (for example, through)
- the holes 71a to 71c are not particularly necessary.
- the holes 71a to 71c may be configured to receive light from the light guide plate.
- the structure provided with only one light receiving element may be sufficient. Even in such a case, multiple access can be realized with a simple configuration.
- Modulating sections 515a to 515c drive white LEDs 40a to 40c based on the current received from current source 514, using the modulated signals modulated by the modulation method as described above as driving currents.
- the white LEDs 40a to 40c output, for example, an optical signal LS whose intensity is modulated according to the received modulated signal.
- the adjustment unit 516 monitors the drive current, temperature, and the like of the white LEDs 40a to 40c by the modulation units 515a to 515c. If there is a deviation from a predetermined value based on the monitoring result, the current source 514 Adjust the output current to the desired value.
- FIG. 11 is a block diagram showing a detailed configuration of the receiving circuit 100. As shown in FIG. As shown in FIG. 11, the receiving circuit 100 is output from the driving circuits 101a to 101c that receive the electric signals converted from the optical signal LS by the light receiving elements 90a to 90c, and the corresponding driving circuits 101a to 101c.
- Demodulator circuits 102a to 102c that demodulate the electrical signal, a restoration unit 103 that restores the separated signals from these demodulation circuits 102a to 102c, and a video signal VS and power control that receives the signal from the restoration unit 103
- a demultiplexer 104 that extracts the signal PS and a power supply control unit 105 on the receiving side that receives the power control signal PS output from the demultiplexer 104 are provided. Further, the video signal VS output from the demultiplexer 104 is supplied to the display control circuit 200.
- the demodulation circuits 102a to 102c included in the reception circuit 100 employ a demodulation method corresponding to the modulation method employed in the modulation units 515a to 515c, and the restoration unit 103 includes the separation unit 512.
- a restoration method corresponding to the multilink method that has been adopted is adopted, and the demultiplexer 104 adopts a demodulation method corresponding to the multiplexing method adopted in the multiplexer 511. Since these methods are well known, a description thereof will be omitted.
- the reception-side power supply control unit 105 performs control to stop the operation of each circuit included in the reception circuit 100 when the power control signal PS received from the demultiplexer 104 becomes inactive. It is assumed that the operation of these circuits is started when a control signal (not shown) is received by the power supply control unit 105 on the receiving side.
- the receiving circuit 100 may further include a carrier detection unit that monitors a current output from one or more of the light receiving elements 90a to 90c.
- This carrier detection unit detects an optical signal by continuously monitoring the presence or absence of the current even when the operation of each circuit included in the reception circuit 100 is stopped.
- the carrier detection unit detects an optical signal
- the carrier detection unit sends a predetermined detection signal to the reception-side power supply control unit 105.
- the reception-side power supply control unit 105 receives this detection signal, each of the reception circuit 100 includes Controls to start circuit operation.
- the carrier that is the detection target of the carrier detection unit is an example, and accurately refers to the light itself, and includes a case where fluorescent light that does not function as a carrier is detected.
- this carrier detection unit When this carrier detection unit is provided, a configuration in which multiplexer 511 and demultiplexer 104 are omitted, that is, a configuration in which power control by power control signal PS is not performed may be employed.
- the carrier detection unit when the carrier detection unit detects an optical signal, it sends an active detection signal to the reception-side power control unit 105, and when the reception-side power control unit 105 receives this active detection signal. Control is performed to start the operation of each circuit included in the receiving circuit 100 (and maintain the operation state during operation).
- the reception-side power control unit 105 detects that the predetermined non-active state is detected.
- the receiving power control unit 105 stops the operation of each circuit included in the receiving circuit 100 (and keeps the stopped state during the stop). I do.
- the receiving-side power control unit 105 may perform control to stop or start the operation of each circuit such as the display control circuit 200 included in the TFT substrate 2 in the same manner as described above. Good. Then, when the operation of the white LEDs 40a to 40c is stopped or started, the operation of each circuit included in the TFT substrate 2 is automatically stopped or started. Therefore, the operation of each circuit included in the TFT substrate 2 is stopped. Power supply control can be performed with a simple configuration. [0113] ⁇ 2. Second Embodiment>
- the white LEDs 40a to 4c are operating, that is, the backlight illumination is performed!
- dimming control is performed in which lighting and extinction are repeated at short time intervals, for example, a frequency that is not visible, such as about 100 [KHz].
- This dimming control is performed by changing the duty ratio indicating the ratio between the lighting time and the lighting time.
- the brightness of the white LEDs 40a to 40c becomes darker as the ratio of the lighting time increases.
- a circuit configuration of the liquid crystal display device when such dimming control is performed will be described.
- the present liquid crystal display device does not receive the power control signal PS, but instead receives the light control parameter signal LC for external power control of the device. .
- the LED drive circuit in this embodiment will be described.
- FIG. 12 is a block diagram showing a detailed configuration of the LED drive circuit 52 according to the second embodiment of the present invention. As shown in FIG. 12, the LED driving circuit 52 receives a dimming parameter signal LC for dimming control from the outside of the liquid crystal display device in place of the power control signal PS received in the first embodiment. receive.
- the multiplexer 511 in the present embodiment receives the video signal VS and the dimming parameter signal LC and multiplexes them. These signals are given to the multiplexer 511 from the outside of the apparatus via the input terminal 59 of the FPC board 50 as described above.
- the dimming parameter signal LC is a parameter for dimming control, and is specifically a numerical value indicating a duty ratio.
- the LED drive circuit 52 is provided in the first embodiment.
- a light control unit 517 for receiving a light control parameter signal LC is provided.
- the dimming control unit 517 outputs a light signal LS, which is modulated by a predetermined PWM (Pulse Width Modulation) method having a duty ratio included in the dimming parameter signal LC, to the white LEDs 40a to 40c. From this, the amount of current applied to the modulators 515a to 515c is changed.
- PWM Pulse Width Modulation
- Fig. 13 is a simplified waveform diagram of the optical signal LS subjected to such dimming control. More specifically, the waveform diagram shown in the upper part of Fig. 13 shows the overall intensity change of the optical signal LS. The waveform diagram shown in the lower part of FIG. 13 is an enlarged view for explaining a part of the intensity change of the optical signal LS.
- the transmitted optical signal LS is modulated by the modulators 515a to 515c.
- the optical signal LS Is not transmitted, naturally, it is not subjected to modulation by the modulation sections 515a to 515c.
- the LED drive circuit 52 in the present embodiment cannot transmit the video signal VS by the optical signal LS during this period. Therefore, the dimming control unit 517 stops signal transmission during this period by controlling the separation unit 512 (or the multiplexer 511).
- the separation unit 512 (or the multiplexer 511) has a predetermined FIFO memory, and data received while signal transmission is stopped is temporarily stored in this memory. To do.
- a detailed configuration of the receiving circuit 120 that receives the optical signal LS subjected to the dimming control as described above will be described.
- FIG. 14 is a block diagram showing a detailed configuration of the receiving circuit 120 in the second embodiment.
- the receiving circuit 120 includes a dimming signal analysis unit 106 that analyzes the received dimming parameter signal LC in place of the receiving-side power supply control unit 105 in the first embodiment.
- the dimming signal analyzer 106 is a dimming parameter demodulated by the demultiplexer 104. Data signal LC is received and a suitable light receiving sensitivity and amplification factor corresponding to the duty ratio included in the dimming parameter signal LC is analyzed. For example, the dimming signal analysis unit 106 stores a table indicating a correspondence relationship between light reception sensitivity and amplification factor suitable for each duty ratio, and calculates the light reception sensitivity and amplification factor based on the correspondence table. . The dimming signal analyzing unit 106 performs control to adjust the light receiving sensitivity and amplification factor of the drive circuits 101a to 101c so as to obtain the calculated light receiving sensitivity and amplification factor.
- the dimming signal analysis unit 106 refers to the duty ratio included in the dimming parameter signal LC, and starts (and ends) the on period and the off period as shown in the lower part of FIG. A signal indicating the start time is given to the demodulation circuits 102a to 102c and the restoration unit 103.
- the dimming signal analysis unit 106 includes a clock recovery circuit including a well-known phase locked circuit (PLL: Phase Locked Loop) circuit that generates a synchronous clock by receiving the video signal VS from the demultiplexer 104, for example. By counting these clocks, it is possible to estimate the start time of the on period and the off period even when the video signal VS is not output.
- PLL Phase Locked Loop
- the demodulation circuits 102a to 102c demodulate the electric signals output from the drive circuits 101a to 101c when the signal indicating that the ON period starts from the dimming signal analysis unit 106, and the OFF period starts.
- the demodulation of the electric signal output from the drive circuits 101a to 101c is stopped.
- the restoration unit 103 restores the separated signals from the demodulation circuits 102a to 102c when receiving a signal indicating that the ON period starts from the dimming signal analysis unit 106, and starts the OFF period.
- the recovery operation is stopped when a signal indicating that the Thus, it is possible to prevent the erroneous video signal VS from being generated by continuing the demodulation operation and the restoration operation even in the off period.
- the restoration unit 103 includes a buffer memory for storing and storing signals including the restored video signal VS, and preferably generates the video signal VS not only during the on period but also during the off period. Masashi.
- the receiving circuit 120 may include a carrier detection unit that monitors the current output from one or more of the light receiving elements 90a to 90c, instead of the dimming signal analysis unit 106. . If this carrier detector is provided, multiplexer 511 and demultiplexer 1 A configuration in which 04 is omitted, that is, a configuration in which the dimming parameter signal LC is not given to the receiving circuit 120 is obtained. In this configuration, when the carrier detection unit detects an optical signal, the carrier detection unit sends an active detection signal to the demodulation circuits 102a to 102c and the restoration unit 103, and when no optical signal is detected, the carrier detection unit transmits to the demodulation circuits 102a to 102c and the restoration unit 103.
- the carrier detection unit stores the lengths of the active period and the inactive period, calculates a duty ratio in the dimming control based on the stored ratios, and is suitable for the duty ratio. Analyze the photosensitivity and amplification factor.
- the carrier detection unit can perform control to adjust the light reception sensitivity and amplification factor of the drive circuit 101a to LOlc so that the calculated light reception sensitivity and amplification factor are obtained.
- This carrier detection unit incorporates a well-known clock recovery circuit having a PLL circuit power. Based on this circuit, a period during which an optical signal is detected and a period during which no optical signal is detected are estimated, and the carrier detection unit appropriately determines The active detection signal or the inactive detection signal may be generated.
- Demodulation circuits 102a to 102c and restoration unit 103 perform demodulation and restoration operations when this detection signal is active, and do not perform demodulation and restoration operations when it is inactive. Thus, it is possible to prevent the erroneous video signal VS from being generated by continuing the demodulation operation and the restoration operation even in the off period.
- the start-stop synchronization method when adopted as the modulation method of the modulation units 515a to 515c, an optical signal including a stop bit is transmitted even when there is no information, so that the demodulation circuits 102a to 102c
- the recovery unit 103 starts demodulation and recovery operation when the carrier detection unit detects a start bit indicating the start of information included in the optical signal, and when the carrier detection unit detects a stop bit. Continues demodulation and restoration. From this, it is not necessary for the signal analysis unit 106 to estimate the start point of the on period and the off period.
- a power supply control unit is newly provided.
- the operation of 0a to 40c is stopped or started, the operation of each circuit included in the TFT substrate 2 is automatically stopped or started, so the power supply control of each circuit included in the TFT substrate 2 is simplified. Can be done.
- the liquid crystal display device is configured not to receive the power control signal PS.
- the liquid crystal display device receives the dimming parameter signal LC and also has the power as in the first embodiment.
- the control signal PS may be received. That is, the liquid crystal display device in the present embodiment can also include the circuit of the liquid crystal display device in the first embodiment.
- the liquid crystal display device according to the present embodiment is provided with a function of reproducing sound in addition to a main function of displaying video. That is, in the present embodiment, the video signal VS is transmitted by the FPC board for video signal transmission having the same configuration as the conventional one, and only the newly given audio signal AS is transmitted by the optical signal. A circuit configuration of the liquid crystal display device in such a case will be described.
- the structure of the liquid crystal display device in the present embodiment is the same as that in the first embodiment, the same components are denoted by the same reference numerals and the description thereof is omitted.
- the overall circuit configuration of the present liquid crystal display device is similar to that of the first embodiment, the same components are denoted by the same reference numerals and description thereof is omitted.
- the video signal VS is directly applied to the display control circuit 200 included in the TFT substrate 20 through the FPC substrate for video signal transmission as in the past, An audio signal AS given to the backlight unit 3 from the outside of the apparatus is converted into an optical signal LSa and transmitted to the TFT substrate 20.
- the circuit configuration of the liquid crystal display device will be described with reference to FIG.
- FIG. 15 is a block diagram showing the configuration of the liquid crystal display device according to the third embodiment of the present invention.
- This liquid crystal display device includes a light receiving element 90 formed on the TFT substrate 20 of the liquid crystal panel 2, a receiving circuit 130, a display control circuit 200 to which a video signal VS is given via an FPC board 58 for transmitting video signals, a video Signal line drive circuit 300, Scanning signal line drive circuit 400 , Display unit 500, audio output circuit 600, and piezoelectric speaker 700, and white LED 40 included in knocklight unit 3 and LED drive circuit 53 that receives audio signal AS
- the LED drive circuit 53 is different from that of the first embodiment in that it receives the audio signal AS, but the internal circuit configuration can be considered in the same way, and the description thereof is omitted. Note that the multiplexer 511 in the LED driving circuit 53 can be omitted. Further, it is necessary when transmitting the power control signal PS or the dimming parameter signal LC.
- the white LED 40 outputs an optical signal LSa obtained by converting (modulating) the audio signal AS.
- the light receiving element 90 receives the optical signal LSa, converts it into an electrical signal, and provides it to the receiving circuit 130.
- this receiving circuit 130 is different from that of the first embodiment in that it outputs the audio signal AS, the internal circuit configuration can be considered in the same way, and the description thereof is omitted. Note that the demultiplexer 104 in the receiving circuit 130 is omitted.
- the audio output circuit 600 receives the audio signal AS from the receiving circuit 130 and drives the piezoelectric speaker 700.
- the audio output circuit 600 has a known circuit configuration, and an example of the circuit will be described with reference to FIG.
- FIG. 16 is a block diagram showing a circuit configuration of the audio output circuit 600.
- the audio output circuit 600 includes a left / right channel synchronization unit 601, a PCM data output unit 602, a data clock control unit 603, a DZA conversion unit 604, and an amplification unit 605.
- the left and right channel synchronization section 601 receives the audio signal AS and outputs a synchronization signal for reproducing the left and right audio in synchronization.
- the PCM data output unit 602 receives the audio signal AS, extracts audio data adopting the PCM (Pulse Code Modulation) method included in the audio signal AS, and supplies the audio data to the DZA conversion unit 604.
- the data clock control unit 603 receives the audio signal AS and reproduces a data clock for synchronization.
- the DZ A conversion unit 604 converts the audio data, which is digital data, into an analog signal based on the synchronization signal and the data clock.
- the amplifying unit 605 drives the analog signal by amplifying the analog signal to a predetermined volume and applying the amplified signal to the piezoelectric speaker 700.
- the audio playback function is exemplified as a typical additional function.
- the function is not limited to this, and is a function added to the liquid crystal display device, and causes signal transmission from the outside.
- the above-described configuration can be widely applied as long as it is to be applied.
- signal transmission for an additional function such as an audio reproduction function may be performed via the FPC, and the video signal VS may be transmitted by an optical signal.
- Multi-link is realized by receiving optical signals transmitting different information from white LEDs 40a to 40c.
- FIG. 17 is a diagram for explaining the positional relationship between the light receiving element and the white LED in the present embodiment.
- the light receiving element 90c is formed on the back surface of the liquid crystal panel 2, that is, the surface opposite to the display surface.
- the black matrix 11 is formed on the surface of the liquid crystal panel 2, that is, on the display surface side.
- the through holes 71a and 71b formed in the resin chassis 70 described above in FIG. 2 are omitted, and only the through holes 71c are formed.
- FIG. 18 is a waveform diagram schematically showing optical signals from the white LEDs 40a to 40c immediately before being received by the light receiving element 90c. It is assumed that the optical signals from the white LEDs 40a to 40c are output simultaneously. Also, these white LEDs 40a-40c are PWM controlled dimming The signal has an on period and an off period shown in FIG.
- the periods (modulation periods or signal transmission periods) that are subject to modulation included in the ON period are determined so as not to overlap each other.
- the period that is not modulated (non-modulation period or non-signal transmission period) and the off period (hereinafter referred to as "guard period" in the on period. ) Does not affect the modulated signal in the modulation period of other optical signals.
- the modulation periods in each optical signal can be determined so as not to overlap.
- signal transmission using the difference in arrival time of light can be easily realized with a simple configuration in which only one light receiving element 90c is provided. Also, with this configuration, signal transmission by white LEDs 40a to 40c is not performed during the non-modulation period, so the load on one white LED can be reduced, and as a result, its light emission life can be extended. .
- the light receiving element 90c is arranged immediately above the white LED 40c.
- the arrangement position of the light receiving element 90c differs depending on the arrival time of light from the white LEDs 40a to 40c. There is no particular limitation as long as the position is generated.
- the number of pins of the FPC board 58 for video signal transmission connected to the TFT board 20 can be increased in the third embodiment. Regardless, it is possible to prevent the increase, and in the first and second embodiments, the FPC board 58 for video signal transmission can be dispensed with.
- the white LEDs 40a to 40c for backlight illumination are also used to transmit optical signals, there is no need to newly provide a light emitting element for light transmission, and the white LEDs 40a to 40c are also backed. Since a circuit driven for light illumination can also be used for generating an optical signal, the manufacturing cost can be reduced.
- the FPC board for video signal transmission can be omitted.
- the power supply for various circuits included in the TFT board 20 (with few pins) FPC board (s) are required.
- FIG. 19 is a plan view showing the FPC for power supply.
- this FPC has a small number of pins, it requires a process of connecting the power supply external to the equipment and the FPC for power supply, and there is a possibility that the connector will be disconnected due to impact or the like. Therefore, in order to solve these problems, for example, first and second modifications as shown in FIGS. 20 and 21 can be considered.
- FIG. 20 is a plan view illustrating a first modification in which power is supplied by a coil instead of the power supply FPC.
- a coil 191 provided in the backlight unit 3 shown in FIG. 20 is supplied with a predetermined alternating current, such as an alternating current source from the outside of the apparatus or an inverter (not shown) that converts the current source 514 for driving the LED into an alternating current.
- a coil 192 formed of a thin film is provided at a predetermined position on the TFT substrate 20 of the liquid crystal panel 2 facing the coil 191.
- a predetermined voltage is applied to the coil 192 by mutual induction of the coils 191, 92. Is excited.
- Each circuit of the TFT substrate 20 is driven by the voltage excited by the coil 192.
- FIG. 21 is a plan view illustrating a second modification in which power is supplied by pins formed on the TFT substrate instead of the power supply FPC.
- a pin 93 provided on the TFT substrate 20 shown in FIG. 21 is provided so as to be in contact with a pin 94 provided at a predetermined position of the facing backlight unit 3.
- a predetermined current is supplied to the pin 94 from a current source external to the device or a current source 514 for driving the LED.
- a current is supplied to each circuit on the TFT substrate 20 through the pin 93 that comes into contact with the pin 94 when the liquid crystal module 4 is formed.
- an element (typically a solar cell) that converts light into current is formed on the TFT substrate 20, and a white LED 4 provided to this element is provided.
- a white LED 4 provided to this element is provided.
- a configuration is conceivable in which the energy of light (or other illumination light or external light) from 0a to 40c is converted into a current, and this current is used as a drive current for each circuit of the TFT substrate 20.
- the above configuration is a force for supplying power to various circuits included in the TFT substrate 20 and can be applied as a configuration for supplying power to the backlight unit 3 in addition to the TFT substrate 20.
- power is supplied to the backlight unit 3 by the FPC board 50, but instead of this, the coil connected to the power supply outside the apparatus and the coil connected by mutual induction,
- the pin force that contacts the pin connected to the power source may be provided in the S backlight unit 3 (or the liquid crystal panel 2).
- the liquid crystal module can be freely inserted and removed from the housing of an external device (for example, a personal computer or a mobile phone) connected to the liquid crystal module. Is possible.
- FIG. 22 is a simplified perspective view for explaining the configuration of the liquid crystal module that can be freely inserted and removed from the casing of the external device.
- a power supply pin 194 connected to a power source (not shown) of the device is provided on the inner surface of the housing 9 of the housing 9 of the external device such as a mobile phone, and the surface of the liquid crystal module 4
- a power receiving pin 193 that can come into contact with the power supply pin 194 is provided at a corresponding position.
- the power supply pin 194 and the power receiving pin 193 come into contact with each other so that power is supplied to the liquid crystal module 4.
- the liquid crystal module 4 can be easily repaired or replaced, and the liquid crystal module 4 can be easily used as a display device for other devices.
- a force using three white LEDs 40a to 40c may be used instead of the red LED, the green LED, and the blue LED.
- the three primary colors of light from these LEDs can be used to obtain a white backlight that is an additive mixed color of these.
- the through holes 71a to 71 formed in the resin chassis 70 shown in FIG. It is preferable that c be provided with a color filter that transmits only the emission color of the LED. Then, it is possible to block light from LEDs other than the LED having a color corresponding to the predetermined light receiving element 90 from reaching the light receiving element 90.
- the color is not necessarily limited to white as long as it is suitable for knocklight illumination, and the type of LED color is not limited. Further, the color of the knocklight illumination light can be appropriately selected by appropriately switching the LED that emits light.
- the white LEDs 40a to 40c may be used only for backlight illumination, and may be configured to have one or more dedicated laser light source powers S for light transmission. In this case, a new laser light source must be provided. By using a laser light source, it is possible to perform light transmission at a higher speed (higher density) than when using an LED. Furthermore, since the arrangement position force of the light receiving element 90 that receives light from the laser light source can be determined regardless of the arrangement position of the LED, for example, an empty space in the TFT substrate 20 (for example, the upper left corner in FIG. 1). The light receiving element 90 can be formed on the substrate.
- the TFT substrate 20 and the backlight unit 3 are fixed in a strict positional relationship in order to realize an optimal liquid crystal display, the distance between the laser light source and the light receiving element 90 is always constant, and individual differences are also present. Since it is difficult to occur, calibration required in a general optical transmission apparatus is not necessary.
- the dedicated laser light source a configuration in which a dedicated LED for light transmission may be provided.
- a deviation can be used as long as it is a light emitting element capable of modulating light intensity such as an organic EL (electroluminescence) element.
- the liquid crystal display device does not necessarily have the backlight unit 3.
- a light emitting type using a reflective display type liquid crystal display device, an organic EL element, or the like It can also be applied to other display devices.
- the through hole 71 is provided on the optical signal path so that the light from the white LED 40 is delivered only to the corresponding light receiving element 90, but the through hole 71 is not provided.
- a known optical fiber, a reflection plate, or the like may be provided instead of the through-hole 71.
- the optical signal path formed by using these well-known optical fibers and reflectors is an alternative to the optical signal path secured by providing the through holes 71.
- all of the white LEDs 40a to 40c transmit the video signal VS.
- white LEDs 40a to 4Oc are used for audio signal transmission.
- one of the white LEDs 40a to 40c is used to transmit an audio signal
- Another white LED may be used to transmit the video signal VS.
- a multi-link system is adopted in which three different white LED 40a-40c and light receiving elements 90a-90c form three different optical transmission paths.
- 1S One of these pairs, For example, only one light transmission path may be formed by the white LED 40c and the light receiving element 90c.
- the light receiving elements 90a and 90b, the separation unit 512, the restoration unit 103, the modulation units 515a and 515b, and the demodulation circuits 102a and 102b are omitted. Further, the through holes 71a and 71b formed in the resin chassis 70 shown in FIG. 2 are also omitted.
- the white LEDs 40a and 40b are not omitted because of the knock light illumination, and these emit light by being directly supplied with a drive current from the current source 514 without passing through the modulation sections 515a and 515b. Further, in this case, the light receiving element 90c may receive light from the white LED 40c after passing through the light guide plate. Then, the light receiving element 90c can be formed in the display unit 500 shown in FIG.
- a plurality of light receiving elements are provided in the display unit 500, and when a well-known image sensor function is realized by these light receiving elements, one or more of these light receiving elements are the above light receiving elements. It may be 90.
- the light receiving element 90 in the display unit 500 has an image sensor function for receiving light from the outside of the apparatus when the white LED 40 is not lit. By receiving the light from after passing through the light guide plate, the optical signal can be received.
- the same drive current including the modulated signal for driving the white LEDs 40a to 40c may be provided from the modulation unit 515c.
- the light receiving element 90c can be formed in the display portion 500.
- the red LED, the green LED, and A configuration using one or more blue LEDs may be used instead of the white LEDs 40a to 40c.
- the red LED, the green LED, and A configuration using one or more blue LEDs may be used instead of the white LEDs 40a to 40c.
- the red LED, the green LED, and A configuration using one or more blue LEDs may be used instead of the white LEDs 40a to 40c.
- the red LED, the green LED, and A configuration using one or more blue LEDs (for example, six) may be used.
- a drive current including a modulated signal is applied to the blue LED from the modulator 515c. It is preferable to use this blue LED for optical transmission.
- an inexpensive cold cathode fluorescent tube may be used instead of the white LEDs 40a to 40c.
- CCFT cold cathode fluorescent tube
- the voltage applied to the CCFT such as modulating the signal output from the inverter for driving the CCFT as a carrier wave, is not possible.
- the optical transmission can be realized with a simple configuration by modulating with a known modulation method.
- the white LED 40 in each of the above embodiments performs backlight illumination for reflection display in the liquid crystal display device, but backlight illumination other than the liquid crystal display device (for example, auxiliary illumination in a dark place).
- illumination may be performed from a direction other than the opposite side of the display surface of the TFT substrate 20 (for example, the horizontal direction).
- dimming control is performed, but the display characteristics of a liquid crystal display device (called a hold type) that maintains the display state in order to improve the blurring of moving image display, etc.
- a hold type a liquid crystal display device
- impulse type the display characteristics
- the ON period and the OFF period can be determined based on the vertical synchronization signal included in the video signal VS, for example, without receiving the dimming parameter signal LC, so that each unit can be controlled based on the determination result.
- signal transmission using the arrival time difference of light according to the distance from the white LEDs 40a to 40c to the light receiving element 90c is realized, but a time difference is provided for lighting of the white LEDs 40a to 40c. That is, by appropriately adjusting the start timing of the modulation period (or guard period) in each optical signal, it can be determined so that the modulation periods in each optical signal do not overlap. In this case as well, the load on one white LED can be reduced, and as a result, its light emission life can be extended.
- the present invention is applied to an active matrix display device including a unit including a display unit such as a liquid crystal panel and a unit that also receives an external force such as a backlight unit. Suitable for matrix display devices.
Description
Claims
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
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CN2006800440325A CN101313352B (zh) | 2005-11-25 | 2006-09-01 | 显示装置 |
EP06797276A EP1965372A4 (en) | 2005-11-25 | 2006-09-01 | VIEW ARRANGEMENT |
US12/094,360 US20100194721A1 (en) | 2005-11-25 | 2006-09-01 | Display device |
JP2007546370A JP5036552B2 (ja) | 2005-11-25 | 2006-09-01 | 表示装置 |
Applications Claiming Priority (2)
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JP2005-340671 | 2005-11-25 | ||
JP2005340671 | 2005-11-25 |
Publications (1)
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WO2007060781A1 true WO2007060781A1 (ja) | 2007-05-31 |
Family
ID=38067018
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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PCT/JP2006/317334 WO2007060781A1 (ja) | 2005-11-25 | 2006-09-01 | 表示装置 |
Country Status (6)
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US (1) | US20100194721A1 (ja) |
EP (1) | EP1965372A4 (ja) |
JP (1) | JP5036552B2 (ja) |
KR (1) | KR100960431B1 (ja) |
CN (1) | CN101313352B (ja) |
WO (1) | WO2007060781A1 (ja) |
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US20100073275A1 (en) * | 2008-09-25 | 2010-03-25 | Jong-Tae Kim | Backlight device and method of driving same |
US20110175856A1 (en) * | 2010-01-15 | 2011-07-21 | Hong Wang-Su | Electrophoretic display panel, method of manufacturing the same and display apparatus having the same |
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JP2017016071A (ja) * | 2015-07-07 | 2017-01-19 | アルパイン株式会社 | 画像表示装置 |
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KR101262179B1 (ko) * | 2007-01-19 | 2013-05-14 | 삼성디스플레이 주식회사 | 표시 장치 및 표시 장치용 케이스 |
CA2665561C (en) * | 2008-05-13 | 2016-01-26 | Dolby Laboratories Licensing Corporation | Array scaling for high dynamic range backlight displays and other devices |
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JP4970606B1 (ja) * | 2011-03-31 | 2012-07-11 | 株式会社東芝 | テレビジョン装置及び電子機器 |
US9337925B2 (en) * | 2011-06-27 | 2016-05-10 | Cree, Inc. | Apparatus and methods for optical control of lighting devices |
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CN110035604A (zh) * | 2018-01-12 | 2019-07-19 | 启耀光电股份有限公司 | 软性电路板、电子装置及其制造方法 |
CN115798365A (zh) * | 2018-04-08 | 2023-03-14 | 北京小米移动软件有限公司 | 显示面板、光电检测方法、装置及计算机可读存储介质 |
CN108964762B (zh) * | 2018-07-23 | 2020-05-29 | 京东方科技集团股份有限公司 | 可见光通信装置及其驱动方法、门锁和可见光通信方法 |
CN116665551A (zh) * | 2020-02-14 | 2023-08-29 | 群创光电股份有限公司 | 电子装置 |
US11823612B2 (en) * | 2021-09-17 | 2023-11-21 | Apple Inc. | Current load transient mitigation in display backlight driver |
CN117116199A (zh) * | 2023-10-20 | 2023-11-24 | 杭州视芯科技股份有限公司 | Led显示屏系统及驱动方法 |
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Also Published As
Publication number | Publication date |
---|---|
JPWO2007060781A1 (ja) | 2009-05-07 |
KR100960431B1 (ko) | 2010-05-28 |
EP1965372A4 (en) | 2011-04-13 |
CN101313352B (zh) | 2011-11-16 |
US20100194721A1 (en) | 2010-08-05 |
JP5036552B2 (ja) | 2012-09-26 |
EP1965372A1 (en) | 2008-09-03 |
KR20080063417A (ko) | 2008-07-03 |
CN101313352A (zh) | 2008-11-26 |
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