KR20110064742A - Back light unit and method driving of the same - Google Patents
Back light unit and method driving of the same Download PDFInfo
- Publication number
- KR20110064742A KR20110064742A KR1020090121458A KR20090121458A KR20110064742A KR 20110064742 A KR20110064742 A KR 20110064742A KR 1020090121458 A KR1020090121458 A KR 1020090121458A KR 20090121458 A KR20090121458 A KR 20090121458A KR 20110064742 A KR20110064742 A KR 20110064742A
- Authority
- KR
- South Korea
- Prior art keywords
- light source
- light
- image data
- green
- red
- Prior art date
Links
Images
Classifications
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/0001—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems
- G02B6/0011—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form
- G02B6/0033—Means for improving the coupling-out of light from the light guide
- G02B6/0035—Means for improving the coupling-out of light from the light guide provided on the surface of the light guide or in the bulk of it
- G02B6/004—Scattering dots or dot-like elements, e.g. microbeads, scattering particles, nanoparticles
- G02B6/0043—Scattering dots or dot-like elements, e.g. microbeads, scattering particles, nanoparticles provided on the surface of the light guide
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/0001—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems
- G02B6/0011—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form
- G02B6/0033—Means for improving the coupling-out of light from the light guide
- G02B6/0058—Means for improving the coupling-out of light from the light guide varying in density, size, shape or depth along the light guide
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/0001—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems
- G02B6/0011—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form
- G02B6/0066—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form characterised by the light source being coupled to the light guide
- G02B6/0073—Light emitting diode [LED]
-
- 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
- G02F1/133603—Direct backlight with LEDs
-
- 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
- G02F1/133615—Edge-illuminating devices, i.e. illuminating from the side
-
- 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
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Nonlinear Science (AREA)
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Mathematical Physics (AREA)
- Crystallography & Structural Chemistry (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Computer Hardware Design (AREA)
- Theoretical Computer Science (AREA)
- Liquid Crystal (AREA)
- Planar Illumination Modules (AREA)
Abstract
The present invention discloses a backlight unit capable of improving image quality.
The disclosed backlight unit includes a red, green, and blue light emitting diode emitting red, green, and blue light, and includes a first light source driven by a scanning method, and a white light emitting diode emitting white light. And a second light source driven by a dimming method, an image data analyzer for analyzing the image data, and a light source driver for selectively driving the first and second light sources according to the image data analyzed from the image data.
Description
The present invention relates to a backlight unit, and more particularly, to a backlight unit capable of improving image quality and a driving method thereof.
Cathode ray tube (CRT), one of the widely used display devices, is mainly used for monitors such as TVs, measuring devices, and information terminal devices, but the size and weight of electronic products are reduced due to the weight and size of CRT itself. Could not actively respond to the response.
As a solution to this problem, the liquid crystal display device has a tendency that its application range is gradually widening due to the features such as light weight, thinning, low power consumption driving. Accordingly, in order to meet the needs of users, liquid crystal display devices are progressing in the direction of large area, thinning, and low power consumption.
BACKGROUND ART A liquid crystal display device is a display device that displays an image by controlling the amount of light passing through a liquid crystal, and is widely used for advantages such as thinning and low power consumption.
Unlike the CRT, the liquid crystal display is not a display device that emits light by itself, and thus, a backlight unit including a separate light source is provided on the back of the liquid crystal display panel to provide light for visually representing an image.
The light source of the backlight unit includes an external eletrode fluorescent lamp (EEFL) covering the outer region of both ends, a cold cathode fluorescent lamp (CCFL) in which electrodes are inserted at both ends of the lamp, and a light emitting diode (LED). : light emitting diode) is used.
In recent years, the backlight unit mainly uses light emitting diodes that are advantageous for low power consumption and slimming.
The backlight unit is divided into an edge method and a direct method according to the position of the light source.
In the edge method, a light source is disposed on the side surface, and the light guide plate is used to convert point light into surface light and provide the light to the liquid crystal display panel. do.
A general backlight unit includes a white light emitting diode that emits white light as an edge light source and a direct light source.
However, a general edge type backlight unit is difficult to implement high brightness by providing light to a liquid crystal display panel through a light guide plate, and a direct light type backlight unit has a problem in that color reproducibility is deteriorated due to characteristics of a white light emitting diode.
It is an object of the present invention to provide a backlight unit and a driving method thereof capable of improving image quality.
The backlight unit according to an embodiment of the present invention,
A first light source comprising red, green and blue light emitting diodes emitting red, green and blue light and driven in a scanning manner; A second light source comprising a white light emitting diode emitting white light and driven by a local dimming method; An image data analyzer analyzing the image data; And a light source driver for selectively driving the first and second light sources according to the image data analyzed from the image data.
In addition, the backlight unit driving method of the present invention,
Driving a first light source emitting red, green and blue light in a scanning manner; Driving a second light source emitting white light in a local dimming manner; Analyzing image data; Generating a control signal for driving the first and second light sources according to the analyzed image data; And selectively driving the first and second light sources by the control signal.
The present invention has a structure comprising a first light source unit disposed on the side to emit red, green and blue light, and a third light source unit disposed below to emit white light, and analyzes the image data. Accordingly, by selecting the edge scanning driving method in which the first and second light source units are driven or the direct local dimming driving in which the third light source unit is driven, color reproduction can be improved and high brightness can be realized.
In addition, the present invention includes a white light emitting diode, red, green and blue light emitting diodes arranged at regular intervals from each other, and analyzes the image data to drive local dimming using a white light emitting diode and using red, green and blue light emitting diodes By selecting the scanning drive, not only can the color reproduction rate be improved, but also high brightness can be realized.
Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.
1 is an exploded perspective view illustrating a liquid crystal display device according to an exemplary embodiment of the present invention, and FIG. 2 is a cross-sectional view illustrating the liquid crystal display device taken along the line II ′ of FIG. 1.
As shown in FIG. 1 and FIG. 2, the liquid crystal display according to the exemplary embodiment of the present invention is provided with a liquid
Although not shown in detail, the liquid
A gate driving printed circuit board (103) for supplying a scan signal to a gate line is provided at an edge of the liquid
The gate and
The
The
Although not shown in the drawings, the
The first and second
The first and second
The plurality of red, green and blue
The
Here, the doped pattern is formed on the lower surface of the
The plurality of third
The white
The driving of the liquid crystal display device having the above structure will be described in detail with reference to FIGS. 3 and 4.
3 is a diagram schematically illustrating a liquid crystal display device according to an exemplary embodiment of the present invention, and FIG. 4 is a diagram illustrating a configuration of a driving unit for driving a backlight unit.
3 and 4, the liquid crystal display according to the exemplary embodiment of the present invention crosses the gate lines GL1 to GLn and the data lines DL1 to DLm and forms liquid crystals formed at the intersections thereof. A liquid
When the scan pulse is sequentially supplied to the gate lines GL1 to GLn, the thin film transistor TFT is turned on to form a channel between the source electrode and the drain electrode to convert the voltage on the data lines DL1 to DLm into the liquid crystal cell. It is supplied to the pixel electrode of (Clc). In this case, the liquid crystal molecules of the liquid crystal cell Clc modulate incident light by changing an arrangement by an electric field between the pixel electrode and the common electrode.
The
The
The
Here, the
The first and second
The
The
According to the present invention, when the image data (RGB data) is a gray-based image including white and black, a direct
When the image data (R, G, B Data) analyzed by the
According to the present invention, when the image data (R, G, B Data) is a brilliant color image in which a plurality of colors are mixed, the edge type scanning driving in which the first and second
As described above, the liquid crystal display of the present invention has first and second light source units (150a and 150b in FIG. 1) disposed on the side to emit red, green and blue light, and disposed below to emit white light. And a third light source unit (180 of FIG. 1), and the first and second
5 is an exploded perspective view illustrating a liquid crystal display according to another exemplary embodiment of the present invention, and FIG. 6 is a plan view illustrating the light source unit of FIG. 5.
5 and 6, the liquid crystal display according to another exemplary embodiment of the present invention is the same as the liquid crystal display according to the exemplary embodiment of the present invention, except that the
The
The
The
The white
The white
The red, green and blue
The red, green, and blue
Driving of the liquid crystal display according to another exemplary embodiment of the present invention is the same as driving according to the exemplary embodiment of FIG. 5.
That is, the
In addition, when the image data is analyzed and the image data is a gray-based image including white and black, the local dimming driving using the white
The
In addition, when the image data is analyzed and the image data is a colorful image in which a plurality of colors are mixed, the scanning driving using the red, green, and blue
As described above, the liquid crystal display according to another exemplary embodiment of the present invention includes white
Those skilled in the art will appreciate that various changes and modifications can be made without departing from the technical spirit of the present invention. Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification but should be defined by the claims.
1 is an exploded perspective view illustrating a liquid crystal display according to an exemplary embodiment of the present invention.
FIG. 2 is a cross-sectional view of the liquid crystal display taken along the line II ′ of FIG. 1.
3 is a schematic view of a liquid crystal display according to an exemplary embodiment of the present invention.
4 is a diagram illustrating a configuration of a driving unit that drives a backlight unit.
5 is an exploded perspective view illustrating a liquid crystal display according to another exemplary embodiment of the present invention.
6 is a plan view illustrating the light source unit of FIG. 5.
Claims (14)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
KR1020090121458A KR20110064742A (en) | 2009-12-08 | 2009-12-08 | Back light unit and method driving of the same |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
KR1020090121458A KR20110064742A (en) | 2009-12-08 | 2009-12-08 | Back light unit and method driving of the same |
Publications (1)
Publication Number | Publication Date |
---|---|
KR20110064742A true KR20110064742A (en) | 2011-06-15 |
Family
ID=44398117
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
KR1020090121458A KR20110064742A (en) | 2009-12-08 | 2009-12-08 | Back light unit and method driving of the same |
Country Status (1)
Country | Link |
---|---|
KR (1) | KR20110064742A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US10698262B2 (en) | 2017-12-27 | 2020-06-30 | Samsung Electronics Co., Ltd. | Display apparatus and method for control thereof |
-
2009
- 2009-12-08 KR KR1020090121458A patent/KR20110064742A/en not_active Application Discontinuation
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US10698262B2 (en) | 2017-12-27 | 2020-06-30 | Samsung Electronics Co., Ltd. | Display apparatus and method for control thereof |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
TWI390495B (en) | Color sequential backlight liquid crystal displays and related methods | |
US8026893B2 (en) | Liquid crystal display device and apparatus and method for driving the same | |
JP5792343B2 (en) | Backlight with video and content control | |
JP5442183B2 (en) | Light generating device, liquid crystal display device having the same, and method for improving color reproducibility of display panel of display device | |
JP2004191490A (en) | Liquid crystal display device | |
US9280941B2 (en) | Liquid crystal display device with direct type backlight and method of driving thereof | |
JP2006323073A (en) | Liquid crystal display device | |
KR101015299B1 (en) | Liquid crystal display device having good image quality | |
US8305332B2 (en) | Backlight unit, liquid crystal display device including the same, and localized dimming method thereof | |
US9520096B2 (en) | Liquid crystal display device | |
KR100964469B1 (en) | Display apparatus | |
JP2007200888A (en) | Backlight assembly and liquid crystal display device having this | |
US9123299B2 (en) | Liquid crystal display device including LED unit using current mirror circuit | |
JP2009031585A (en) | Liquid crystal display device | |
KR20080000825A (en) | Control device and method of backlight of liquid crystal display device | |
US8976104B2 (en) | Display device and driving method thereof | |
KR20080073950A (en) | Backlight unit and liquid crystal display having the same | |
US20070216843A1 (en) | Liquid crystal display and backlight controlling method | |
CN101853644B (en) | Display and color adjustment method for the same | |
KR20110064742A (en) | Back light unit and method driving of the same | |
KR20080063432A (en) | Circuit for controlling a backlight in a liquid crystal display | |
KR100685432B1 (en) | Liquid Crystal Display Device for having a common backlight unit used in LCD of FS-driving type or LCD of CF-driving type | |
KR101687804B1 (en) | Apparatus and method for liquid crystal display device | |
TWI420489B (en) | Field sequential liquid crystal display and driving method thereof | |
KR20170079435A (en) | Liquid crystal display device |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
WITN | Withdrawal due to no request for examination |