Invented by Sung-Chon Park, Won-Kyu Kwak, Yang-Wan Kim, Samsung Display Co Ltd
The Samsung Display Co Ltd invention works as followsIn an organic light-emitting diode (OLED) display, a plurality sub-pixels that share a scan line that extends along a row direction form a unit-pixel. The plurality sub-pixels of the unit-pixel are arranged in column-direction. The field is divided into subfields and the corresponding subpixel emits light for each subfield.
Background for Display device and driving method thereof
The present invention is a display device, and its driving method, more specifically an organic light-emitting diode display device, and the driving method therefor.
In general the organic light-emitting diode is a display for electrically stimulating phosphorous organic material and emitting light. The organic light-emitting diode displays images by driving organic light emission cell arranged in matrix format. Organic light emitting diode is the name given to an organic light emission diode with a diode-like characteristic. It has a structure that includes an anode electrolyte layer, organic thin film and cathode electrical layer. The organic thin film is combined with holes and electrons that are injected via the anode and cathode electrodes. This produces light. “The organic light emitting cell emits light in different amounts depending on injected electrons and hole amounts, i.e., the current applied.
In a display such as an organic light emitting device display device, each pixel has a sub-pixel that emits one of several colors (e.g. primary colors of light), with colors represented by combinations of these colors. A pixel generally includes a red (R) sub-pixel, a green (G) sub-pixel, and a blue (B) sub-pixel. Colors are represented by combinations of the RGB colors. The sub-pixels will usually be arranged along the row direction in order R, G and B.
Each subpixel in the organic LED display device contains a driving transistor to drive the organic diode and a switching transistor. Each sub-pixel also has a line to transmit (or apply) a signal and another line to transmit (or apply) a voltage. Many wires are needed to transmit (or apply) voltages or signal to the transistors, capacitors and other components of each pixel. The wires are difficult to place in the pixels, and this reduces the ratio of light emission areas.
One exemplary embodiment provides a display for improving an aperture.
Another exemplary embodiment provides a display for simplifying the arrangements of wires and other elements in units pixels.
Yet another exemplary embodiment provides a display for reducing the number of selected scan lines.
Further a further exemplary embodiment provides a scanner driver for reducing the number of flip-flops.
In one aspect, the invention provides a display device with a plurality unit pixels, multiple data lines, multiple select scan lines and multiple emit scan lines. A field is divided up into several subfields. The rows of unit pixels display an image in the field. Each unit pixel includes a number of light emitting components arranged in the column direction. The data signals are transmitted by the plurality of lines that extend in a column direction. The select scan lines are arranged in a row-wise direction, transmitting select signals. Each select scan line is connected to one of the rows within the unit pixels. The plurality emit scans transmit emission control signal, and each emit scan is coupled to one of the rows in the unit pixels. In each of the subfields, the scan driver applies select signals to select scan lines and emission control signals on emit scan lines. “At least one unit pixel uses a data signal corresponding to one of one or more of one or more of one or more of one’s select signals and emits light when a emit signal from a respective one of emission control signals is applied to one of its subfields.
In another aspect of the invention, there is a display device that includes a plurality unit pixels, data lines in multiples, select scan lines in multiples, emit scan lines in multiples, first scan driver and second scan driver. A field is divided up into several subfields. The rows of unit pixels display an image in the field. Each unit pixel includes a number of light emitting components arranged in the column direction. The data lines are arranged in a column direction. They transmit data signals. The select scan lines are arranged in a row-wise direction, transmitting select signals. Each select scan line is connected to the corresponding row of unit pixels. The plurality emit scans transmit emission control signal, and each emit scan is coupled to one of the rows. In each of the subfields, the first scan driver applies select signals to select scan lines from a row group of unit pixels. The emission control signals are then applied to the emit scanning lines in the row group. In each of the subfields, the second scan driver applies select signals to select scan lines from a second group of unit pixels. The emission control signals are then applied to the emit scanning lines in the second group. “At least one unit pixel uses a data signal corresponding to a select signal corresponding to the first signal, and each of its plurality of light-emitting elements emits light corresponding to the emit signal in a subfield corresponding to the second row group.
In a further aspect of the invention, there is a method for driving pixel circuits of a display. Display device with a number of data lines extending in one direction, transmitting data signals. A plurality select scan lines extending in the other direction, transmitting select signals. Each unit pixel has a number of sub-pixels. A select signal is applied to one of a plurality select scan lines of a subfield in the first field and a data signal is applied on one of a plurality data lines. A first emission signal is applied to one or more of the unit pixels that receive a select signal and data signals. This results in a sub-pixel emitting light. One of the select signals must be applied to one of a plurality select scan lines within a second subfield, and one of each of the data lines must be applied to one of a plurality data lines. “A second emission control is applied to one or more of the unit pixels where a respective one of select signals and acorresponding one data signal are applied, so that a sub-pixel emits light in the second direction. The first and second subpixels of the plurality are arranged along the first direction.
In a further aspect, the present invention provides a display unit that includes a display area and two drivers. The display area comprises a number of data lines extending in a first-direction, a number of select scan lines extending in a second-direction, and a multitude of unit pixels. Each unit pixel includes a number of sub-pixels that are arranged in the direction of the first scan line. The first driver transmits sequentially select signals to each of the select scan lines of each of the subfields that make up a field and emits emission control signals in order to emit light at the at least one subpixel in each subfield. The second driver transmits data to at least one data line of each unit pixel coupled to the select scan line to which the selected signal is applied. The first driver produces the emission control signal corresponding to each subfield using a shift signal.
In the following detailed description only certain exemplary embodiments are shown and described simply as an illustration. The described embodiments can be modified in many different ways without departing from spirit or scope.
Accordingly the drawings and descriptions are to be considered as illustrative and not restrictive. The specification may not discuss parts that are shown or not shown on the drawings because they are not necessary to understand the invention. Like reference numerals designate like elements. Phrases like ‘one thing is coupled with another’ are used. The phrase “a first thing is directly coupled with a second” can be used to refer to either “a first one that is directly coupled to another one?” “The first one is directly coupled to a second one?
The exemplary embodiments will describe a display device, a driving technique for it and an organic LED display device that uses an organic LED as a light-emitting element.
As shown in FIG. The organic light emitting display device comprises a display area (100) that appears as a screen for the user, a scanning driver 200 and a data controller 300.
The display area (100) includes a number of data lines D1-Dm, a number of select scan lines, S1-Sn, as well as a group of emit scan lines Em11-Em1n and Em21-2n. It also contains a large number of unit pixels, 110. Each unit pixel includes two subpixels 111, 112, which are arranged along a column. The data lines D1-Dm are extended along a column and transmit images as data signals to the unit pixels. Select scan lines S1-Sn are extended along a row and transmit select signals that select corresponding lines in order to send data signals to unit pixels. The emit scanlines Em11 to Em1n, and Em21-Em2n, are extended in row direction. They transmit emission control signals to control light emission from the respective subpixels 111 and 112 at the unit pixels 110. The unit pixel is defined by the intersection of the select scan lines (S1 to Sn) and the data lines D1-Dm. The scan lines S1-Sn are connected to the subpixels 111 and 112.
The scan driver 200 transmits sequentially select signals from the subfields S1 to Sn to the subfields. The scan driver sends sequential emission control signals to control light emission from the subpixels 111 on the emit scan line Em11 to Em1n of one subfield and sequential emission control signal to control light emission from the subpixels 112 on the emit scanner lines Em21to Em2n of the other subfield. Data driver 300 sequentially applies select signals to lines and then sends data signals to data lines D1-Dm corresponding to pixels on those lines. The data driver 300 also applies data to the subpixels 111 of the first subfield and data to the subpixels 112 of the second subfield.
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