US20100277459A1 - Liquid crystal display device including a circuit board including an inverter with a driving circuit - Google Patents
Liquid crystal display device including a circuit board including an inverter with a driving circuit Download PDFInfo
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- US20100277459A1 US20100277459A1 US12/774,635 US77463510A US2010277459A1 US 20100277459 A1 US20100277459 A1 US 20100277459A1 US 77463510 A US77463510 A US 77463510A US 2010277459 A1 US2010277459 A1 US 2010277459A1
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- voltage
- driving
- light source
- unit
- lcd 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
- G09G3/34—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
- G09G3/3611—Control of matrices with row and column drivers
-
- 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
-
- 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
- G02F1/13454—Drivers integrated on the active matrix substrate
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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
- G09G2300/00—Aspects of the constitution of display devices
- G09G2300/04—Structural and physical details of display devices
- G09G2300/0421—Structural details of the set of electrodes
- G09G2300/0426—Layout of electrodes and connections
-
- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G2330/00—Aspects of power supply; Aspects of display protection and defect management
- G09G2330/02—Details of power systems and of start or stop of display operation
-
- 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
-
- 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
- G09G3/3611—Control of matrices with row and column drivers
- G09G3/3696—Generation of voltages supplied to electrode drivers
Definitions
- the present invention relates to a liquid crystal display, and more particularly, to a liquid crystal display comprising an inverter providing a light source driving voltage to a light source.
- a liquid crystal display (hereinafter, referred to as ‘LCD’) is a device displaying an image, with liquid crystal cells aligned in a matrix form where the light transmittance of the cells is adjusted according to an image signal.
- the LCD forms an image on an LCD panel using light radiated from a backlight unit.
- the LCD comprises an LCD panel on which liquid crystal cells formed in a pixel unit and aligned in a matrix form are formed, a driving part driving the liquid crystal cells, a driving circuit part provided with a circuit pattern to control the driving part, a backlight unit uniformly providing light to the LCD panel, a bottom chassis accommodating the above and an inverter providing a voltage to the backlight unit.
- the driving part comprises a driving chip and a FPC (flexible printed circuit) on which the driving chip is mounted and the driving circuit part comprises a voltage converter converting inputted voltages into needed voltage values and a circuit pattern generating a signal to control the driving part.
- the driving circuit part is connected to one side of the FPC and disposed on rear of the bottom chassis.
- the inverter generates a light source control signal controlling and driving a light source and provides a light source driving voltage to a light source part according to the light source control signal.
- the inverter is manually screwed on one side or the rear surface of the bottom chassis.
- the driving circuit part comprises a voltage converter converting inputted voltages into at least one of voltages needed to drive the LCD, such as a gate-on voltage, a gate-off voltage, a reference voltage (AVDD) and etc.
- AVDD reference voltage
- the voltage converter generates a high reference voltage so as to improve high image quality and response time, the voltage converter is disadvantageously overloaded.
- a liquid crystal display comprising an LCD panel on which an electrode pad is provided; a driving part connected to the electrode pad and applying a driving signal to the LCD panel; a light source part providing light to the LCD panel; and a circuit board comprising a driving circuit part applying a driving control signal to the driving part and an inverter providing a light source driving voltage to the light source part.
- LCD liquid crystal display
- the LCD further comprises a light guiding plate disposed on the LCD panel and a bottom chassis accommodating the light guiding plate, wherein the light source part is disposed along one side of the light guiding plate.
- the circuit board is disposed on a rear surface of the bottom chassis where the light source part is disposed.
- the circuit board further comprises a voltage converter
- the voltage converter comprises a transformer converting a direct current voltage into an alternating current voltage.
- the voltage converter converts voltages inputted from outside into a driving circuit voltage provided to the driving circuit part and the light source driving voltage provided to the inverter, respectively.
- the driving circuit voltage comprises at least one of a gate-on voltage, a gate-off voltage and a reference voltage, and is applied to the driving circuit part.
- the light source part comprises a light source irradiating light to a rear surface of the LCD panel and wires connecting the light source and the inverter, respectively, and the inverter generates a light source controlling signal to control and drive the light source part and has a connecting terminal connected to the wires.
- the light source driving voltage comprises an initial driving voltage turning on the light source part, a normal driving voltage applied to the light source part after the initial driving voltage is applied, and an excess driving voltage applied when the light source part is not driven by the initial driving voltage.
- the connecting terminal is disposed on one edge of the circuit board.
- the light source part comprises one of a CCFL (Cold Cathode Fluorescent Lamp) and an EEFL (External Electrode Fluorescent Lamp).
- CCFL Cold Cathode Fluorescent Lamp
- EEFL External Electrode Fluorescent Lamp
- the driving circuit part and the inverter are respectively provided by the surface mount technology (SMT) on the same circuit board.
- SMT surface mount technology
- a voltage-providing connector and a voltage converter are provided on the driving circuit part, and the voltage converter converts voltages inputted through the voltage-providing connector into a gate-on voltage or a gate-off voltage.
- a voltage-providing connector and a voltage converter are provided on the inverter and the voltage converter coverts voltages inputted through the voltage-providing connector into a light-driving voltage and a reference voltage, respectively.
- the reference voltage is applied to the driving circuit part.
- a voltage-providing connector and a voltage converter are provided on the inverter, and the voltage converter converts voltages inputted through the voltage-providing connector into a driving circuit voltage and a light-providing voltage, respectively.
- the driving circuit voltage comprises at least one of a gate-on voltage, a gate-off voltage and a reference voltage and is applied to the driving circuit part.
- FIG. 1 is an exploded perspective view of an LCD according to a first embodiment of the present invention
- FIG. 2 is a cross-sectional view of the LCD of FIG. 1 ;
- FIG. 3 is a plane view of a rear of a bottom chassis of FIG. 1 ;
- FIG. 4 is a plane view of a rear of a bottom chassis according to a second embodiment of the present invention.
- FIG. 1 is an exploded perspective view of an LCD
- FIG. 2 is a cross-sectional view of the LCD
- FIG. 3 is a plane view of a rear of a bottom chassis according to a first embodiment of the present invention.
- an LCD 1 comprises an LCD panel 10 on which an image is displayed; a driving part 20 driving the LCD panel 10 ; a driving circuit part 31 controlling the driving part 20 ; a mold frame 40 supporting a circumference of the LCD panel 10 ; a backlight unit 90 radiating light to a rear of the LCD panel 10 ; a bottom chassis 100 accommodating and supporting the backlight unit 90 and the mold frame 40 , and an inverter 39 providing a voltage to the backlight unit 90 .
- the driving circuit part 31 and the inverter 39 are provided on the same circuit board 30 .
- the LCD panel 10 comprises a TFT (Thin Film Transistor) substrate 11 , a color filter substrate 12 adhered facing the TFT substrate 11 and a liquid crystal, not shown, interposed between the two substrates. Also, the LCD panel 10 further comprises polarizers (not shown) respectively adhered on a front surface of the color filter substrate 12 and on a rear surface of the TFT substrate 11 so that light passing through the LCD panel 10 is crossly polarized.
- polarizers (not shown) respectively adhered on a front surface of the color filter substrate 12 and on a rear surface of the TFT substrate 11 so that light passing through the LCD panel 10 is crossly polarized.
- On the above-mentioned LCD panel 10 are aligned liquid crystal cells formed in a pixel unit and aligned in a matrix form. The liquid crystal cells generate an image by adjusting the light transmittance through the liquid crystal cells according to an image signal transmitted from the driving part 20 .
- a plurality of gate lines and a plurality of data lines are formed on the TFT substrate 11 in a matrix form and a TFT (not shown) is formed at the intersection of the gate line and the data line.
- a signal voltage transmitted from the driving part 20 is applied between a pixel electrode and a common electrode of the color filter substrate 12 . Under the control of the TFT, the liquid crystal between the pixel electrode and the common electrode is aligned by the signal voltage, thereby determining light transmittance.
- the color filter substrate 12 comprises color filters on which a red, a green and a blue or a cyan, a magenta and a yellow color filter are repeatedly formed on the boundary of a black matrix and a common electrode.
- the common electrode is comprised of transparent conductive substance such as ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), or etc.
- the color filter substrate 12 has a smaller area than the TFT substrate 11 .
- the driving part 20 comprises a driving chip 21 to apply a driving signal and a FPC (flexible printed circuit) 23 on which the driving chip 21 is mounted using a COF (chip on film) method and a first side of the FPC 23 is connected to an end of the gate line or the data line of the TFT substrate 11 .
- the driving part 20 is extended to a rear of bottom chassis 100 with the FPC 23 being bent.
- the liquid crystal disposed between the TFT substrate 11 and the color filter substrate 12 moves in response to the driving signal from the driving part 20 and is realigned accordingly.
- circuit board 30 On the same circuit board 30 are provided a driving circuit part 31 connected to a second side of the FPC and provided with a circuit pattern to control the driving chip 21 , and an inverter 39 providing or intercepting voltage to a light source part 60 mentioned later.
- the circuit board 30 may preferably be disposed on rear of the bottom chassis 100 where the light source part 60 is disposed.
- the driving circuit part 31 comprises the circuit board 30 on which a circuit pattern is provided in order to control the driving part 20 and is connected to one side of the driving part 20 extended to the rear of the bottom chassis 100 and is disposed on the rear of the bottom chassis 100 .
- a voltage-providing connector 32 to be provided with a voltage from an external or an internal battery or etc. and a voltage converting part 33 to convert inputted voltages into needed voltages. Inputted voltages provided to the voltage-providing connector 32 are provided to the voltage converter part 33 .
- the voltage converting part 33 may further comprise a transformer (not shown) converting direct current voltages applied from the inverter 39 into alternating current voltages and converts inputted voltages into driving circuit voltages and light source driving voltages, thereby respectively providing to the driving circuit part 31 and to the inverter 39 .
- the driving circuit voltages comprise at least one of a gate-on voltage, a gate-off voltage and a reference voltage (VADD).
- a common voltage, a gray scale voltage and a voltage used for the driving circuit part 31 are generated from the reference voltage.
- a driving control signal is generated on the circuit pattern provided on the driving circuit part 31 to control the driving part 20 (See FIG. 1 ) and at least one of the gate-on voltage, the gate-off voltage, the common voltage and the gray scale voltage is transmitted to the driving part 20 in response to the driving control signal.
- the inverter 39 is affixed to one side of the same circuit board 30 where the driving circuit part 31 is provided.
- the inverter 39 is applied with the light source driving voltage from the voltage converter 33 provided on the driving circuit part 31 .
- the inverter 39 generates the light source control signal to control and drive the light source part 60 (See FIG. 1 ).
- the inverter 39 comprises a connecting terminal 37 connected to wires 65 of the light source part 60 .
- the connecting terminal 37 is an accessory connected to the wires 65 and providing the voltage applied to the inverter 39 to the light source part 60 and is disposed on one edge of the circuit board 30 . Accordingly, the light source part 60 and the inverter 39 are connected with short wires 65 and the inverter 39 can provide a desired voltage to the light source part 60 .
- the inverter 39 generates the light source control signal to control and drive the light source part 60 .
- the inverter 39 provides one of an initial driving voltage to turn on the light source part, a normal driving voltage provided to the light source part after the initial driving voltage is applied and an excess driving voltage provided when the light source part 60 may not be driven.
- the light source part 60 is controlled according to the light source control signal based on the light source driving voltage provided from the voltage converting part 33 .
- the initial driving voltage should have about two times or more of voltage level as the normal driving voltage. This is due to a characteristic of the CCFL or the EEFL mainly used for the light source part 60 . That is, in those lamps is arisen an electron emission when a strong electric field is given on a surface of the cathode, therefore high voltage is required to initially drive those lamps. After the initial driving, the normal driving voltage is applied to stably drive those lamps. However, there are situations where the light source part 60 is not driven by the initial driving voltage due to circumference influence or the like. In this case, after a sensor senses whether the light source part 60 is driven by the initial driving voltage or not, the excess driving voltage higher than the initial driving voltage is provided to the light source part 60 when the light source part 60 is not being driven.
- the aforementioned inverter 39 is planned and is manufactured through the Surface Mount Technology (SMT) on the same circuit board 30 when the driving circuit part 31 is planed and is manufactured at the same time or separately.
- SMT Surface Mount Technology
- providing the driving circuit part 31 and the inverter 39 in a single process may remove an additional process step providing and assembling a conventional inverter. Therefore, manufacturing process and processing cost may efficiently be decreased.
- space utility of the LCD becomes efficient.
- a conventional voltage applied to the driving circuit part 31 through the voltage converter 33 may respectively generate the driving circuit voltage used for the driving circuit part 31 and the light source driving voltage used for the inverter 39 , it is not needed to provide boosted voltage or convert a voltage with an additional component in the driving circuit part 31 and the inverter 39 . Accordingly, there may be a voltage decreasing effect and an additional material such as connecting wires or a connector may be needed.
- the mold frame 40 is formed along a circumference of the LCD panel 10 , has a nearly rectangular shape and supports the LCD panel 10 separately from the backlight unit 90 .
- the backlight unit 90 disposed in rear of the LCD panel 10 comprises optical sheets 50 , the light source part 60 , a light guiding plate 70 and a reflecting sheet 80 .
- the optical sheets 50 comprise a protection sheet 51 disposed in rear of the LCD panel 10 , a prism sheet 53 and a diffusion sheet 55 .
- the diffusion sheet 55 comprises a base plate and a coating layer having beads formed on the base plate.
- the diffusion sheet 55 diffuses light from the lamp and provides the light to the LCD panel 10 .
- Two or three sheets of the overlapping diffusion sheet 55 may be used.
- On the prism sheet 53 may be formed a triangular prism at a predetermined alignment.
- the prism sheet 53 concentrates light diffused from the diffusion sheet 55 in the perpendicular direction of a surface of the LCD panel 10 .
- the prism sheet 53 is used in a pair and the micro prism formed on the each prism sheet 53 makes a predetermined angle with each other. Light passing through the prism sheet 53 progresses perpendicularly, thereby forming a uniform brightness distribution.
- the protection sheet 51 disposed on the top of the prism sheet 53 protects the prism sheet 53 which is vulnerable to scratching.
- the light source part 60 comprises a light source 61 generating light, an electrode 63 provided at both ends of the light source 61 , a wire 65 connected to the electrode 63 and a reflector 67 encompassing the light source 61 .
- the light source 61 is connected to the inverter 39 through the wires 65 and is provided with the desired driving voltage.
- the electrode 63 and the wire 65 are soldered.
- the light source 61 is disposed along one side of the light guiding plate 70 .
- the lamp may be disposed at both sides of the light guiding plate 70 or a plurality of lamps may be disposed parallel between the two sides of the light guiding plate 70 .
- a CCFL Cold Cathode Florescent Lamp
- various lamps such as HCFL (Heat Cathode Florescent Lamp) or EEFL (External Electrode Florescent Lamp) may be used.
- the light guiding plate 70 is disposed along one side of the light source 61 and is disposed in the rear of the LCD panel 10 , thereby leading light generated from the light source 61 to the backside of the LCD panel 10 .
- the light guiding plate 70 comprises an incident surface provided with light from the light source 61 , an exiting surface forming a perpendicular angle to the incident surface and disposed parallel with the LCD panel 10 and the rear surface on which a pattern is formed so that light irradiated from the light source 61 progresses to the exiting surface.
- the light guiding plate 70 converts light irradiated to the incident surface from the light source 61 , which is disposed along one side of the light guiding plate 70 , in other words, adjacent to the incident surface, into plane light and equally transmits light to the LCD panel 10 through the exiting surface.
- Material of the light guiding plate 70 may use PMMA (Polymethylmethacrylate) having a high strength, therefore not easily being transformed or being broken and having a good transmittance.
- the light guiding plate 70 may be formed in a wedge type having a flat upper surface and a slant lower surface, or in a plate type having flat upper and lower surfaces.
- the light guiding plate 70 in a trapezoid-shaped may be used and the light source 61 may be provided on the lateral side of its one side which is thicker than its other side.
- the reflecting sheet 80 being disposed between the light source 61 and the bottom chassis 100 reflects light from the light source 61 and provides the reflected light to the diffusion sheet 55 .
- the reflecting sheet 80 is made of PET (polyethylene terephthalate) or PC (polycarbonate).
- the reflecting sheet 80 decreases light loss by reflecting light to the light guiding plate 70 , which is leaked in the opposite direction of the LCD panel 10 through the light guiding plate 70 and contributes to improving the uniformity of light transmitted in the direction of the LCD panel 10 from the light guiding plate 70 .
- a top chassis 5 comprises a display window so that a displaying area of the LCD panel 10 may be exposed to the outside, accommodates the mold frame 40 and is combined with the bottom chassis 100 .
- the bottom chassis 100 accommodates the backlight unit 90 and the mold frame 40 , and is combined with the top chassis 5 .
- the LCD 1 of the present invention it is not necessary to provide separate voltages to the driving circuit part 31 and to the inverter 39 respectively or to convert the voltage with an additional process, since the driving circuit voltage used in driving circuit part 31 and the light source driving voltage used in the inverter 39 may respectively be generated from the voltage provided to the conventional driving circuit part through the voltage converting part 33 .
- FIG. 4 is a plane view of a rear of a bottom chassis according to a second embodiment of the present invention.
- a driving circuit part 131 and an inverter 139 are respectively provided on the same circuit board 130 .
- Voltage providing connectors 141 , 146 and voltage converters 142 , 147 are respectively provided on the driving circuit part 131 and on the inverter 139 .
- the voltage providing connector 141 of the driving circuit part 131 is applied with a desired voltage, for example, 3.3V voltage, and converts the desired voltage into at least one of a gate-on voltage, a gate-off voltage and a reference voltage (VADD) which is needed in the voltage converter 142 .
- the reference voltage (VADD) is converted into a common voltage, a gray scale voltage and a voltage needed in the driving circuit part 131 .
- 21V for the gate-on voltage, ⁇ 7V for the gate-off voltage and 8V.about.12V for the reference voltage are used respectively.
- the voltage converter 142 of the driving circuit part 131 generates the aforementioned high voltage and the high reference voltage (VADD) to improve image quality and response time, the voltage converter 142 is electrically loaded. Therefore, power consumption increases.
- the driving circuit part 131 and the inverter 139 are provided on the same circuit board 130 .
- the voltage converter 142 of the driving circuit part 131 is planned to convert voltages inputted through the voltage providing connector 141 into the gate-on voltage and the gate-off voltage and the voltage converter 147 of the inverter 139 is planned to convert voltages inputted through the voltage providing connector 142 into the light source driving voltage and the reference voltage (VADD).
- VADD reference voltage
- the reference voltage (VADD) converted in the voltage convert 147 of the inverter 139 is provided to the driving circuit part 131 .
- the reference voltage (VADD) is generated in the voltage converter 147 of the inverter 139 and provided to the driving circuit part 131 .
- power consumption may be decreased.
- the voltage providing connector and the voltage converter may be provided only in the inverter.
- Voltage inputted to the inverter through the voltage providing connector is converted into the driving circuit voltage and the light source providing voltage in the voltage converter and the driving circuit voltage is provided to the driving circuit part.
- the driving circuit voltage comprises at least one of the gate-on voltage, the gate-off voltage and the reference voltage, and is converted into at least one of the gate-on voltage, the gate-off voltage and the reference voltage in the inverter 139 and may be provided to the driving circuit part 131 or may be converted in the driving circuit part 131 .
Abstract
A liquid crystal display (LCD) comprising an LCD panel on which an electrode pad is provided; a driving part connected to the electrode pad and applying a driving signal to the LCD panel; a light source part providing light to a rear surface of the LCD panel; and a circuit board comprising a driving circuit part applying a driving control signal to the driving part and an inverter providing a light source driving voltage to the light source part. Accordingly, the LCD may improve work efficiency in a modular assembly process and decrease voltage overload of a voltage converter.
Description
- This application is a continuation of, and claims benefit of U.S. Ser. No. 11/340,381 filed Jan. 26, 2006, where the latter claims the benefit of Korean Patent Application No. 2005-0039381, filed on May 11, 2005, in the Korean Intellectual Property Office, where the disclosures of said US application and said Korean application are incorporated herein by reference in their entireties.
- 1. Field of the Invention
- The present invention relates to a liquid crystal display, and more particularly, to a liquid crystal display comprising an inverter providing a light source driving voltage to a light source.
- 2. Description of the Related Art
- Generally, a liquid crystal display (hereinafter, referred to as ‘LCD’) is a device displaying an image, with liquid crystal cells aligned in a matrix form where the light transmittance of the cells is adjusted according to an image signal. The LCD forms an image on an LCD panel using light radiated from a backlight unit.
- The LCD comprises an LCD panel on which liquid crystal cells formed in a pixel unit and aligned in a matrix form are formed, a driving part driving the liquid crystal cells, a driving circuit part provided with a circuit pattern to control the driving part, a backlight unit uniformly providing light to the LCD panel, a bottom chassis accommodating the above and an inverter providing a voltage to the backlight unit.
- Here, the driving part comprises a driving chip and a FPC (flexible printed circuit) on which the driving chip is mounted and the driving circuit part comprises a voltage converter converting inputted voltages into needed voltage values and a circuit pattern generating a signal to control the driving part. The driving circuit part is connected to one side of the FPC and disposed on rear of the bottom chassis.
- The inverter generates a light source control signal controlling and driving a light source and provides a light source driving voltage to a light source part according to the light source control signal. The inverter is manually screwed on one side or the rear surface of the bottom chassis.
- However, since the driving circuit part and the inverter are respectively disposed on the predetermined places by hand work and it takes a long time in a modular assembly process of the LCD, working efficiency becomes low. Accordingly, mass-production of the LCD is adversely affected.
- Moreover, the driving circuit part comprises a voltage converter converting inputted voltages into at least one of voltages needed to drive the LCD, such as a gate-on voltage, a gate-off voltage, a reference voltage (AVDD) and etc. However, as the voltage converter generates a high reference voltage so as to improve high image quality and response time, the voltage converter is disadvantageously overloaded.
- Accordingly, it is an aspect of the present invention to provide a liquid crystal display improving efficiency in a modular assembly process and decreasing overload of a voltage converter.
- The foregoing and/or other aspects of the present invention are achieved by providing a liquid crystal display (LCD) comprising an LCD panel on which an electrode pad is provided; a driving part connected to the electrode pad and applying a driving signal to the LCD panel; a light source part providing light to the LCD panel; and a circuit board comprising a driving circuit part applying a driving control signal to the driving part and an inverter providing a light source driving voltage to the light source part.
- According to the embodiment of the present invention, the LCD further comprises a light guiding plate disposed on the LCD panel and a bottom chassis accommodating the light guiding plate, wherein the light source part is disposed along one side of the light guiding plate.
- According to the embodiment of the present invention, the circuit board is disposed on a rear surface of the bottom chassis where the light source part is disposed.
- According to the embodiment of the present invention, the circuit board further comprises a voltage converter
- According to the embodiment of the present invention, the voltage converter comprises a transformer converting a direct current voltage into an alternating current voltage.
- According to the embodiment of the present invention, the voltage converter converts voltages inputted from outside into a driving circuit voltage provided to the driving circuit part and the light source driving voltage provided to the inverter, respectively.
- According to the embodiment of the present invention, the driving circuit voltage comprises at least one of a gate-on voltage, a gate-off voltage and a reference voltage, and is applied to the driving circuit part.
- According to the embodiment of the present invention, the light source part comprises a light source irradiating light to a rear surface of the LCD panel and wires connecting the light source and the inverter, respectively, and the inverter generates a light source controlling signal to control and drive the light source part and has a connecting terminal connected to the wires.
- According to the embodiment of the present invention, the light source driving voltage comprises an initial driving voltage turning on the light source part, a normal driving voltage applied to the light source part after the initial driving voltage is applied, and an excess driving voltage applied when the light source part is not driven by the initial driving voltage.
- According to the embodiment of the present invention, the connecting terminal is disposed on one edge of the circuit board.
- According to the embodiment of the present invention, the light source part comprises one of a CCFL (Cold Cathode Fluorescent Lamp) and an EEFL (External Electrode Fluorescent Lamp).
- According to the embodiment of the present invention, the driving circuit part and the inverter are respectively provided by the surface mount technology (SMT) on the same circuit board.
- According to the embodiment of the present invention, a voltage-providing connector and a voltage converter are provided on the driving circuit part, and the voltage converter converts voltages inputted through the voltage-providing connector into a gate-on voltage or a gate-off voltage.
- According to the embodiment of the present invention, a voltage-providing connector and a voltage converter are provided on the inverter and the voltage converter coverts voltages inputted through the voltage-providing connector into a light-driving voltage and a reference voltage, respectively.
- According to the embodiment of the present invention, the reference voltage is applied to the driving circuit part.
- According to the embodiment of the present invention, a voltage-providing connector and a voltage converter are provided on the inverter, and the voltage converter converts voltages inputted through the voltage-providing connector into a driving circuit voltage and a light-providing voltage, respectively.
- According to the embodiment of the present invention, the driving circuit voltage comprises at least one of a gate-on voltage, a gate-off voltage and a reference voltage and is applied to the driving circuit part.
- The above and/or other aspects and advantages of the present invention will become apparent and more readily appreciated from the following description of the exemplary embodiments, taken in conjunction with the accompanying drawings of which:
-
FIG. 1 is an exploded perspective view of an LCD according to a first embodiment of the present invention; -
FIG. 2 is a cross-sectional view of the LCD ofFIG. 1 ; -
FIG. 3 is a plane view of a rear of a bottom chassis ofFIG. 1 ; and -
FIG. 4 is a plane view of a rear of a bottom chassis according to a second embodiment of the present invention. - Reference will now be made in detail to exemplary embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. The embodiments are described below in order to explain the present invention by referring to the figures.
-
FIG. 1 is an exploded perspective view of an LCD,FIG. 2 is a cross-sectional view of the LCD, andFIG. 3 is a plane view of a rear of a bottom chassis according to a first embodiment of the present invention. - Referring to
FIG. 1 , anLCD 1 comprises anLCD panel 10 on which an image is displayed; a drivingpart 20 driving theLCD panel 10; adriving circuit part 31 controlling the drivingpart 20; amold frame 40 supporting a circumference of theLCD panel 10; abacklight unit 90 radiating light to a rear of theLCD panel 10; abottom chassis 100 accommodating and supporting thebacklight unit 90 and themold frame 40, and aninverter 39 providing a voltage to thebacklight unit 90. Here, thedriving circuit part 31 and theinverter 39 are provided on thesame circuit board 30. - The
LCD panel 10 comprises a TFT (Thin Film Transistor)substrate 11, acolor filter substrate 12 adhered facing theTFT substrate 11 and a liquid crystal, not shown, interposed between the two substrates. Also, theLCD panel 10 further comprises polarizers (not shown) respectively adhered on a front surface of thecolor filter substrate 12 and on a rear surface of theTFT substrate 11 so that light passing through theLCD panel 10 is crossly polarized. On the above-mentionedLCD panel 10 are aligned liquid crystal cells formed in a pixel unit and aligned in a matrix form. The liquid crystal cells generate an image by adjusting the light transmittance through the liquid crystal cells according to an image signal transmitted from the drivingpart 20. - A plurality of gate lines and a plurality of data lines are formed on the
TFT substrate 11 in a matrix form and a TFT (not shown) is formed at the intersection of the gate line and the data line. A signal voltage transmitted from thedriving part 20 is applied between a pixel electrode and a common electrode of thecolor filter substrate 12. Under the control of the TFT, the liquid crystal between the pixel electrode and the common electrode is aligned by the signal voltage, thereby determining light transmittance. - The
color filter substrate 12 comprises color filters on which a red, a green and a blue or a cyan, a magenta and a yellow color filter are repeatedly formed on the boundary of a black matrix and a common electrode. The common electrode is comprised of transparent conductive substance such as ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), or etc. Thecolor filter substrate 12 has a smaller area than theTFT substrate 11. - The driving
part 20 comprises adriving chip 21 to apply a driving signal and a FPC (flexible printed circuit) 23 on which thedriving chip 21 is mounted using a COF (chip on film) method and a first side of the FPC 23 is connected to an end of the gate line or the data line of theTFT substrate 11. Thedriving part 20 is extended to a rear ofbottom chassis 100 with the FPC 23 being bent. The liquid crystal disposed between theTFT substrate 11 and thecolor filter substrate 12 moves in response to the driving signal from thedriving part 20 and is realigned accordingly. - On the
same circuit board 30 are provided adriving circuit part 31 connected to a second side of the FPC and provided with a circuit pattern to control thedriving chip 21, and aninverter 39 providing or intercepting voltage to alight source part 60 mentioned later. In order to stably provide a voltage to thelight source part 60 with short wires connecting thelight source part 60 and theinverter 39, thecircuit board 30 may preferably be disposed on rear of thebottom chassis 100 where thelight source part 60 is disposed. - The driving
circuit part 31 comprises thecircuit board 30 on which a circuit pattern is provided in order to control the drivingpart 20 and is connected to one side of the drivingpart 20 extended to the rear of thebottom chassis 100 and is disposed on the rear of thebottom chassis 100. - Referring to
FIG. 3 , on one side of the drivingcircuit part 31 are provided a voltage-providingconnector 32 to be provided with a voltage from an external or an internal battery or etc. and avoltage converting part 33 to convert inputted voltages into needed voltages. Inputted voltages provided to the voltage-providingconnector 32 are provided to thevoltage converter part 33. Thevoltage converting part 33 may further comprise a transformer (not shown) converting direct current voltages applied from theinverter 39 into alternating current voltages and converts inputted voltages into driving circuit voltages and light source driving voltages, thereby respectively providing to the drivingcircuit part 31 and to theinverter 39. - The driving circuit voltages comprise at least one of a gate-on voltage, a gate-off voltage and a reference voltage (VADD). A common voltage, a gray scale voltage and a voltage used for the driving
circuit part 31 are generated from the reference voltage. A driving control signal is generated on the circuit pattern provided on the drivingcircuit part 31 to control the driving part 20 (SeeFIG. 1 ) and at least one of the gate-on voltage, the gate-off voltage, the common voltage and the gray scale voltage is transmitted to the drivingpart 20 in response to the driving control signal. - The
inverter 39 is affixed to one side of thesame circuit board 30 where the drivingcircuit part 31 is provided. Theinverter 39 is applied with the light source driving voltage from thevoltage converter 33 provided on the drivingcircuit part 31. Theinverter 39 generates the light source control signal to control and drive the light source part 60 (SeeFIG. 1 ). Theinverter 39 comprises a connectingterminal 37 connected towires 65 of thelight source part 60. The connectingterminal 37 is an accessory connected to thewires 65 and providing the voltage applied to theinverter 39 to thelight source part 60 and is disposed on one edge of thecircuit board 30. Accordingly, thelight source part 60 and theinverter 39 are connected withshort wires 65 and theinverter 39 can provide a desired voltage to thelight source part 60. - The
inverter 39 generates the light source control signal to control and drive thelight source part 60. Theinverter 39 provides one of an initial driving voltage to turn on the light source part, a normal driving voltage provided to the light source part after the initial driving voltage is applied and an excess driving voltage provided when thelight source part 60 may not be driven. Thelight source part 60 is controlled according to the light source control signal based on the light source driving voltage provided from thevoltage converting part 33. - Here, the initial driving voltage should have about two times or more of voltage level as the normal driving voltage. This is due to a characteristic of the CCFL or the EEFL mainly used for the
light source part 60. That is, in those lamps is arisen an electron emission when a strong electric field is given on a surface of the cathode, therefore high voltage is required to initially drive those lamps. After the initial driving, the normal driving voltage is applied to stably drive those lamps. However, there are situations where thelight source part 60 is not driven by the initial driving voltage due to circumference influence or the like. In this case, after a sensor senses whether thelight source part 60 is driven by the initial driving voltage or not, the excess driving voltage higher than the initial driving voltage is provided to thelight source part 60 when thelight source part 60 is not being driven. - The
aforementioned inverter 39 is planned and is manufactured through the Surface Mount Technology (SMT) on thesame circuit board 30 when the drivingcircuit part 31 is planed and is manufactured at the same time or separately. Likewise, providing the drivingcircuit part 31 and theinverter 39 in a single process may remove an additional process step providing and assembling a conventional inverter. Therefore, manufacturing process and processing cost may efficiently be decreased. Furthermore, when the drivingcircuit part 31 and theinverter 39 are provided in thesame circuit board 30, space utility of the LCD becomes efficient. When the drivingcircuit part 31 and theinverter 39 are assembled in asingle circuit board 30, work efficiency in a modular assembly process may be improved. - Moreover, since a conventional voltage applied to the driving
circuit part 31 through thevoltage converter 33 may respectively generate the driving circuit voltage used for the drivingcircuit part 31 and the light source driving voltage used for theinverter 39, it is not needed to provide boosted voltage or convert a voltage with an additional component in the drivingcircuit part 31 and theinverter 39. Accordingly, there may be a voltage decreasing effect and an additional material such as connecting wires or a connector may be needed. - Referring back to
FIGS. 1 and 2 , themold frame 40 is formed along a circumference of theLCD panel 10, has a nearly rectangular shape and supports theLCD panel 10 separately from thebacklight unit 90. - The
backlight unit 90 disposed in rear of theLCD panel 10 comprisesoptical sheets 50, thelight source part 60, alight guiding plate 70 and a reflectingsheet 80. - The
optical sheets 50 comprise aprotection sheet 51 disposed in rear of theLCD panel 10, aprism sheet 53 and adiffusion sheet 55. Thediffusion sheet 55 comprises a base plate and a coating layer having beads formed on the base plate. Thediffusion sheet 55 diffuses light from the lamp and provides the light to theLCD panel 10. Two or three sheets of the overlappingdiffusion sheet 55 may be used. On theprism sheet 53 may be formed a triangular prism at a predetermined alignment. Theprism sheet 53 concentrates light diffused from thediffusion sheet 55 in the perpendicular direction of a surface of theLCD panel 10. Typically, theprism sheet 53 is used in a pair and the micro prism formed on the eachprism sheet 53 makes a predetermined angle with each other. Light passing through theprism sheet 53 progresses perpendicularly, thereby forming a uniform brightness distribution. Theprotection sheet 51 disposed on the top of theprism sheet 53 protects theprism sheet 53 which is vulnerable to scratching. - The
light source part 60 comprises alight source 61 generating light, anelectrode 63 provided at both ends of thelight source 61, awire 65 connected to theelectrode 63 and areflector 67 encompassing thelight source 61. Thelight source 61 is connected to theinverter 39 through thewires 65 and is provided with the desired driving voltage. Here, theelectrode 63 and thewire 65 are soldered. Thelight source 61 is disposed along one side of thelight guiding plate 70. Although not shown in the figure, the lamp may be disposed at both sides of thelight guiding plate 70 or a plurality of lamps may be disposed parallel between the two sides of thelight guiding plate 70. - In the exemplary embodiment, a CCFL (Cold Cathode Florescent Lamp) is used as the
light source 61, but various lamps such as HCFL (Heat Cathode Florescent Lamp) or EEFL (External Electrode Florescent Lamp) may be used. - The
light guiding plate 70 is disposed along one side of thelight source 61 and is disposed in the rear of theLCD panel 10, thereby leading light generated from thelight source 61 to the backside of theLCD panel 10. Thelight guiding plate 70 comprises an incident surface provided with light from thelight source 61, an exiting surface forming a perpendicular angle to the incident surface and disposed parallel with theLCD panel 10 and the rear surface on which a pattern is formed so that light irradiated from thelight source 61 progresses to the exiting surface. Accordingly, thelight guiding plate 70 converts light irradiated to the incident surface from thelight source 61, which is disposed along one side of thelight guiding plate 70, in other words, adjacent to the incident surface, into plane light and equally transmits light to theLCD panel 10 through the exiting surface. Material of thelight guiding plate 70 may use PMMA (Polymethylmethacrylate) having a high strength, therefore not easily being transformed or being broken and having a good transmittance. Here, thelight guiding plate 70 may be formed in a wedge type having a flat upper surface and a slant lower surface, or in a plate type having flat upper and lower surfaces. In case of an LCD employed to a small-sized product such as notebook PC or cellular phone, thelight guiding plate 70 in a trapezoid-shaped may be used and thelight source 61 may be provided on the lateral side of its one side which is thicker than its other side. - The reflecting
sheet 80 being disposed between thelight source 61 and thebottom chassis 100 reflects light from thelight source 61 and provides the reflected light to thediffusion sheet 55. The reflectingsheet 80 is made of PET (polyethylene terephthalate) or PC (polycarbonate). The reflectingsheet 80 decreases light loss by reflecting light to thelight guiding plate 70, which is leaked in the opposite direction of theLCD panel 10 through thelight guiding plate 70 and contributes to improving the uniformity of light transmitted in the direction of theLCD panel 10 from thelight guiding plate 70. - A
top chassis 5 comprises a display window so that a displaying area of theLCD panel 10 may be exposed to the outside, accommodates themold frame 40 and is combined with thebottom chassis 100. - The
bottom chassis 100 accommodates thebacklight unit 90 and themold frame 40, and is combined with thetop chassis 5. - In the following description, the function and efficiency of the
LCD 1 having the abovementioned formation will be described. First, according to theLCD 1 of the present invention, it is not necessary to provide separate voltages to the drivingcircuit part 31 and to theinverter 39 respectively or to convert the voltage with an additional process, since the driving circuit voltage used in drivingcircuit part 31 and the light source driving voltage used in theinverter 39 may respectively be generated from the voltage provided to the conventional driving circuit part through thevoltage converting part 33. - Furthermore, work efficiency in a modular assembly process may be improved, since the driving
circuit part 31 and theinverter 39 are provided on thesame circuit board 30 and are assembled in a single process. Also, the manufacturing cost may be decreased, since an additional process which comprises planning and manufacturing the conventional inverter and assembling it may be removed and it is not needed to use additional connecting wires and the connector. - Hereinbelow, an LCD according to a second embodiment of the present invention will be described with reference to
FIG. 4 . -
FIG. 4 is a plane view of a rear of a bottom chassis according to a second embodiment of the present invention. - Referring to
FIG. 4 , a drivingcircuit part 131 and aninverter 139 are respectively provided on thesame circuit board 130.Voltage providing connectors voltage converters circuit part 131 and on theinverter 139. - Generally, the
voltage providing connector 141 of the drivingcircuit part 131 is applied with a desired voltage, for example, 3.3V voltage, and converts the desired voltage into at least one of a gate-on voltage, a gate-off voltage and a reference voltage (VADD) which is needed in thevoltage converter 142. The reference voltage (VADD) is converted into a common voltage, a gray scale voltage and a voltage needed in the drivingcircuit part 131. Usually, 21V for the gate-on voltage, −7V for the gate-off voltage and 8V.about.12V for the reference voltage are used respectively. As thevoltage converter 142 of the drivingcircuit part 131 generates the aforementioned high voltage and the high reference voltage (VADD) to improve image quality and response time, thevoltage converter 142 is electrically loaded. Therefore, power consumption increases. - In the exemplary embodiment, the driving
circuit part 131 and theinverter 139 are provided on thesame circuit board 130. Thevoltage converter 142 of the drivingcircuit part 131 is planned to convert voltages inputted through thevoltage providing connector 141 into the gate-on voltage and the gate-off voltage and thevoltage converter 147 of theinverter 139 is planned to convert voltages inputted through thevoltage providing connector 142 into the light source driving voltage and the reference voltage (VADD). As a result, an electrical load of thevoltage converter 147 may be decreased. Further, the reference voltage (VADD) converted in the voltage convert 147 of theinverter 139 is provided to the drivingcircuit part 131. Likewise, by providing the drivingcircuit part 131 and theinverter 139 in asingle circuit board 130, the reference voltage (VADD) is generated in thevoltage converter 147 of theinverter 139 and provided to the drivingcircuit part 131. As a result, power consumption may be decreased. - Furthermore, although not shown in the embodiment, the voltage providing connector and the voltage converter may be provided only in the inverter. Voltage inputted to the inverter through the voltage providing connector is converted into the driving circuit voltage and the light source providing voltage in the voltage converter and the driving circuit voltage is provided to the driving circuit part. The driving circuit voltage comprises at least one of the gate-on voltage, the gate-off voltage and the reference voltage, and is converted into at least one of the gate-on voltage, the gate-off voltage and the reference voltage in the
inverter 139 and may be provided to the drivingcircuit part 131 or may be converted in the drivingcircuit part 131. - Although several embodiments in accordance with the present teachings have been shown and described, it will be appreciated by those skilled in the pertinent art and in light of the foregoing that changes and modifications may be made in these embodiments without departing from the principles and spirit of the present teachings.
Claims (21)
1-17. (canceled)
18. A liquid crystal display (LCD) device comprising:
an LCD panel on which an electrode pad is provided;
a driving part connected to the electrode pad to apply a driving signal to the LCD panel;
a backlight unit including a light source part providing light to the LCD panel;
a voltage converter part receiving an inputted voltage to generate a driving circuit voltage and a light source driving voltage; and
a circuit board comprising a first unit receiving the driving circuit voltage and applying a driving control signal to the driving part, and a second unit receiving the light source driving voltage and providing a desired voltage to the light source part,
wherein the voltage converter part is coupled to the circuit board.
19. The LCD device of claim 18 , wherein the second unit is disposed to one side of the same circuit board where the first unit is provided.
20. The LCD device of claim 18 , further comprising a receiving unit accommodating the backlight unit.
21. The LCD device of claim 20 , wherein the circuit board is disposed on a rear surface of the receiving unit.
22. The LCD device of claim 21 , wherein the driving part is extended to the rear surface of the receiving unit.
23. The LCD device of claim 22 , wherein the circuit board is connected to one side of the driving part.
24. The LCD device of claim 18 , further comprising a light guiding plate disposed on the LCD panel,
wherein the light source part is disposed along one side of the light guiding plate.
25. The LCD device of claim 18 , wherein the voltage converter part comprises a single voltage converter located on the circuit board.
26. The LCD device of claim 25 , wherein the voltage converter comprises a transformer converting a direct current voltage into an alternating current voltage.
27. The LCD device of claim 18 , wherein the voltage converter part comprises:
a first voltage converter structured to convert voltages inputted from outside into a driving circuit voltage provided to the first unit; and
a second voltage converter structured to convert the voltage inputted from outside into the light source driving voltage provided to the second unit.
28. The LCD device of claim 27 , wherein the driving circuit voltage comprises at least one of a gate-on voltage, a gate-off voltage and a reference voltage.
29. The LCD device of claim 18 , wherein
the light source part comprises a light source irradiating light to a rear surface of the LCD panel and wires connecting the light source and the second unit, respectively, and
the second unit generates the light source control signal to control and drive the light source part and has a connecting terminal connected to the wires.
30. The LCD device of claim 29 , wherein the connecting terminal is disposed on one edge of the circuit board.
31. The LCD device of claim 18 , wherein the light source driving voltage comprises an initial driving voltage turning on the light source part, a normal driving voltage applied to the light source part after the initial driving voltage is applied, and an excess driving voltage applied when the light source part is not driven by the initial driving voltage.
32. The LCD device of claim 18 , wherein the first unit and the second unit are respectively provided by the surface mount technology (SMT) on the same circuit board.
33. The LCD device of claim 18 , wherein a voltage-providing connector and the voltage converter are provided on the first unit, and the voltage converter converts voltages inputted through the voltage-providing connector into a gate-on voltage or a gate-off voltage.
34. The LCD device of claim 33 , wherein the driving circuit voltage comprises at least one of a gate-on voltage, a gate-off voltage and a reference voltage and is applied to the first unit.
35. The LCD device of claim 18 , wherein a voltage-providing connector and the voltage converter are provided on the second unit and the voltage converter coverts voltages inputted through the voltage-providing connector into a light driving voltage and a reference voltage, respectively.
36. The LCD device of claim 35 , wherein the reference voltage is applied to the first unit.
37. The LCD device of claim 18 , wherein a voltage-providing connector and the voltage converter are provided on the second unit, and the voltage converter converts voltages inputted through the voltage-providing connector into a driving circuit voltage and a light-providing voltage, respectively.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US12/774,635 US20100277459A1 (en) | 2005-05-11 | 2010-05-05 | Liquid crystal display device including a circuit board including an inverter with a driving circuit |
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
KR1020050039381A KR101148198B1 (en) | 2005-05-11 | 2005-05-11 | Liquid crystal display |
KR2005-0039381 | 2005-05-11 | ||
US11/340,381 US7746316B2 (en) | 2005-05-11 | 2006-01-26 | Liquid crystal display device including a circuit board including an inverter with a driving circuit part |
US12/774,635 US20100277459A1 (en) | 2005-05-11 | 2010-05-05 | Liquid crystal display device including a circuit board including an inverter with a driving circuit |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
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US11/340,381 Continuation US7746316B2 (en) | 2005-05-11 | 2006-01-26 | Liquid crystal display device including a circuit board including an inverter with a driving circuit part |
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US20100277459A1 true US20100277459A1 (en) | 2010-11-04 |
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US12/774,635 Abandoned US20100277459A1 (en) | 2005-05-11 | 2010-05-05 | Liquid crystal display device including a circuit board including an inverter with a driving circuit |
Family Applications Before (1)
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US11/340,381 Active 2028-08-27 US7746316B2 (en) | 2005-05-11 | 2006-01-26 | Liquid crystal display device including a circuit board including an inverter with a driving circuit part |
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KR (1) | KR101148198B1 (en) |
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TWI554990B (en) * | 2011-01-19 | 2016-10-21 | 三星顯示器有限公司 | Display device |
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KR100672653B1 (en) * | 2004-04-30 | 2007-01-24 | 엘지.필립스 엘시디 주식회사 | Backlight unit and liquid crystal display device having the same |
TWI370297B (en) * | 2007-02-12 | 2012-08-11 | Chimei Innolux Corp | Back light module for liquid crystal display |
KR101361517B1 (en) * | 2007-02-26 | 2014-02-24 | 삼성전자 주식회사 | Backlight unit, liquid crystal display and control method of the same |
WO2009050911A1 (en) * | 2007-10-17 | 2009-04-23 | Sharp Kabushiki Kaisha | Lighting equipment for display device, display device, and television receiver |
KR101620024B1 (en) * | 2009-02-27 | 2016-05-13 | 삼성디스플레이 주식회사 | Display apparatus and method of assembling the same |
KR101645236B1 (en) * | 2010-02-23 | 2016-08-04 | 삼성디스플레이 주식회사 | Transformer and Liquid Crystal Display Apparatus having the Same |
CN103091884B (en) * | 2013-01-07 | 2016-03-30 | 华为终端有限公司 | Hand-hold electronic equipments |
KR102200255B1 (en) * | 2014-11-24 | 2021-01-07 | 엘지디스플레이 주식회사 | Liquid crystal display |
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Also Published As
Publication number | Publication date |
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US20060267918A1 (en) | 2006-11-30 |
US7746316B2 (en) | 2010-06-29 |
KR20060116874A (en) | 2006-11-15 |
CN1862325A (en) | 2006-11-15 |
KR101148198B1 (en) | 2012-05-23 |
CN100437243C (en) | 2008-11-26 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: SAMSUNG DISPLAY CO., LTD, KOREA, REPUBLIC OF Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:SAMSUNG ELECTRONICS, CO., LTD;REEL/FRAME:028990/0423 Effective date: 20120904 |
|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |