TWI419120B - Multi-line addressing methods and apparatus - Google Patents

Description

Multi-line addressing method and device (1) Field of invention

The present invention relates to a method and apparatus for driving emission, and more particularly to an organic light emitting diode (OLED) display element using multi-line addressing (MLA) technology. The specific examples of the invention are particularly suitable for use in so-called passive matrix OLED display elements. This case is one of a group of three related applications, and the three cases share the same priority application date.

Background of the invention

Multi-wire addressing techniques for liquid crystal display elements (LCDs) have been described, for example, in US 2004/150608, US 2002/158832, and US 2002/083655, to reduce the power consumed and to increase the relatively slow response rate of the LCD. However, these technologies are not suitable for OLED display elements due to the difference caused by the basic difference between OLED and LCD. In other words, OLED is a transmission technology, and LCD is a type modulator. In addition, the OLED provides a substantially linear response to the applied current, while the LCD unit cell has a non-linear response, and the nonlinear response of the LCD changes according to the RMS (root mean square) value of the applied voltage.

Display elements fabricated using OLEDs offer a number of advantages over LCDs and superior to other flat panel technologies. Display elements made using OLEDs (Comparative LCDs) are brighter, more colorful, fast switching, provide a wide viewing angle, and are easy and inexpensive to manufacture on a variety of substrates. Organic (including organometallic herein) LEDs can be fabricated using materials including polymers, small molecules, and dendrimers, and the color range is determined by the materials employed. Examples of polymer-based organic LEDs are described in WO 90/13148, WO 95/06400 and WO 99/48160; examples of dendritic oligomer-based materials are described in WO 99/21935 and WO 02/067343; Examples of molecular devices are described in U.S. Patent 4,539,507.

A typical OLED device comprises two layers of organic material, one of which is a layer of luminescent material, such as a layer of luminescent polymer (LEP), oligomer or luminescent low molecular weight material; and the other layer is a layer of hole transport material, such as a polythiophene derivative or Polyaniline derivative layer.

The organic LEDs can be deposited on the substrate in a pixel matrix form to form a single color or colorful pixelated display element. The colorful display elements can be composed of multiple sets of pixels that emit red light, green light, and blue light. The so-called active matrix display elements have memory elements associated with the individual pixels, typically storage capacitors and transistors; while passive matrix display elements do not have such memory elements, but rather are repeatedly scanned to obtain the impression of a stable image. Other passive display elements include segmented display elements in which multiple segments share a common electrode and one segment can be illuminated by applying a voltage to the other electrodes. A simple segmented display element does not require scanning, but in a display element that includes multiple segmented regions, the electrodes can be multiplexed (to reduce their number) and then scanned.

Figure 1a shows a longitudinal section view of an example of an OLED element 100. In the active matrix display element, a portion of the pixel area is occupied by an associated drive circuit (not shown in Figure 1a). The device structure is somewhat simplified for illustration.

OLED 100 comprises a substrate 102, typically 0.7 mm or 1.1 mm glass, but may alternatively be a clear plastic or some other substantially transparent material. The anode layer 104 is deposited on a substrate which typically comprises ITO (indium tin oxide) having a thickness of about 150 nm and a metal contact layer on a portion of the substrate. Typically, the contact layer comprises about 500 nanometers of aluminum, or a layer of aluminum is sandwiched between two layers of chromium, occasionally referred to as an anode metal. Glass substrates coated with ITO and contact metal are available from Corning, USA. The contact metal above the ITO assists in providing a path of reduced resistance where the anode connection need not be transparent, particularly as a contact external to the device that does not need to be transparent. The contact metal is removed from the undesired location of the ITO, particularly at locations where it may be obscured by standard lithography procedures, followed by etching.

A substantially transparent hole transport layer 106 is deposited over the anode layer, followed by deposition of the electroluminescent layer 108 and cathode 110. The electroluminescent layer 108 includes, for example, PPV (poly(p-phenylene vinyl)); the hole transport layer 106 can assist in matching the hole level of the anode layer 104 with the electroluminescent layer 108, the hole transport layer 106 A conductive transparent polymer is included, such as PEDOT:PSS (polystyrene-sulfonate doped polyethylene-dimethoxythiophene) available from Bayer AG, Germany. In a typical polymer based component, the hole transport layer 106 comprises about 200 nanometers PEDOT; the light emitting polymer layer 108 typically has a thickness of about 70 nanometers. These organic layers may be deposited by spin coating followed by plasma etching or laser ablation to remove material from undesired regions, or by inkjet printing. In the latter case, the bank 112 can be formed on the substrate, for example using a photoresist to define the well and an organic layer to be deposited in the well. Such a well can define a light emitting region or pixel of the display element.

Cathode layer 110 typically comprises a low work function metal such as calcium or strontium (e.g., deposited by physical vapor deposition) covered by a thicker aluminum cap layer. Alternatively, additional layers may be placed in close proximity to the electroluminescent layer, such as a lithium fluoride layer, to improve the matching of the electronic energy levels. The mutual electrical insulation of the cathode wires can be achieved or enhanced by the use of a cathode spacer (not shown in Figure 1a).

The same basic structure can also be used for small molecule elements and dendritic oligomer elements. A plurality of display elements are typically fabricated on a single substrate, and the substrate is cut at the end of the manufacturing process, the individual display elements are separated, and then the cans are attached to the respective display elements to inhibit oxidation and moisture intrusion.

To illuminate the OLED, power is applied between the anode and the cathode by the battery 118, as shown in Figure 1a. In the example shown in Fig. 1a, the transparent anode 104 and the substrate 102 emit light, and the cathode is generally reflective; such an element is referred to as a "bottom emitting element". It is also possible to form an element that emits light through the cathode ("top emitting element"), for example, maintaining the thickness of the cathode layer 110 at less than about 50-100 nm, leaving the cathode substantially transparent.

The organic LEDs can be deposited on the substrate in a pixel matrix form to form a single color or colorful pixelated display element. The colorful display elements can be composed of multiple sets of red, green and blue luminescent pixels. In such a display element, an individual component typically selects a pixel by exciting a column line (or a row line), and writes a plurality of columns of pixels (or a plurality of rows of pixels) to form a display element. The so-called active matrix display element has memory elements associated with each pixel, typically a storage capacitor and a transistor, while a passive matrix display element does not have such a memory element, but instead repeats scanning to obtain a stable image impression, repeated scanning It is slightly similar to the image of a TV set.

Referring now to Figure 1b, a simplified cross-sectional view of a passive matrix OLED display element 150 is shown, wherein elements similar to those of Figure 1a are labeled with the same reference numerals. As shown, the hole transport layer 106 and the electroluminescent layer 108 are subdivided into a plurality of pixels 152 at the intersection of the anode and cathode lines perpendicular to the ions of the anode metal layer 104 and the cathode layer 110, respectively. The figure shows a conductive line 154 defined by the cathode layer 110 entering the plane of the paper, and a cross-sectional view through one of the plurality of anode lines 158 at right angles to the cathode line. Electroluminescent pixel 152 at the intersection of the cathode line and the anode line can be addressed by applying a voltage between the two associated lines. The anode metal layer 104 provides external contacts to the display element 150, and the anode metal layer 104 can be used as an OLED to anode connection and a cathode connection (the cathode layer pattern is routed over the anode metal extraction).

The OLED material, in particular, the luminescent polymer and the cathode are sensitive to oxidation and sensitive to moisture, so the OLED component is encapsulated in the inside of the metal can 111, and the ultraviolet curable epoxy resin 113 is attached to the anode metal layer 104. Small glass beads inside the glue prevent metal from contacting the contacts and causing a short circuit.

Referring now to Figure 2, this figure shows the drive arrangement of the passive matrix OLED display element 150 of the type shown in Figure 1b. A plurality of constant current generators 200 are provided, each connected to the power supply line 202 and coupled to one of the plurality of row lines 204. For clarity, only one row line is shown. A plurality of column lines 206 (only one of which is shown) are also provided, and each column line can be selectively coupled to the ground line 208 by a switch link 210. As shown, the power supply line 202 has a positive supply voltage. The row line 204 includes an anode connection 158 and the column line 206 includes a cathode connection 154. However, if the power supply line 202 is negative, the connection to the ground line 208 can be reversed.

As shown, the pixel 212 of the display element has a power source applied thereto and thus emits light. To form an image, a column of links 210 maintains the column connections as the rows are alternately intensified until the entire column is addressed, then selects the next column and repeats the process. However, in order to allow individual pixels to maintain conduction for a long time, the overall driving level can be shortened, a column is selected, and all rows are written in parallel. In other words, current is simultaneously driven to each row line to illuminate each column of one column. Its predetermined brightness. Individual pixels in a row can be alternately addressed before the next row is addressed, but this is not good because of the capacitive effect of the row.

Those skilled in the art understand that in passive matrix OLED display elements, the electrodes can be arbitrarily labeled as column electrodes and labeled as row electrodes. In this specification, "columns" and "rows" are used interchangeably.

The OLED provides a current-controlled drive instead of a voltage-controlled drive because the OLED brightness is determined by the current flowing through the display element, which determines the number of photons produced. In the voltage-controlled configuration, the brightness can vary across the entire display element and varies with time, temperature, and age, so when driven by a specified voltage, it is difficult to predict the brightness that the pixel will appear. In color display elements, the accuracy of color rendering is also affected.

Conventional methods for changing pixel brightness use pulse width modulation (PWM) to change the on-time of a pixel. In the conventional PWM system, one pixel is fully open or fully closed, but the brightness of the pixel's name changes due to the internal integration of the viewer's eyes. Another method is to change the row drive current.

Figure 3 shows a schematic diagram 300 of a general drive component circuit of a passive matrix OLED display element in accordance with the prior art. The OLED display elements are indicated by dashed lines 302 and include n column lines 304, each having a respective column electrode contact 306, and m row lines 308 having respective plurality of row electrode contacts 310. The OLED is connected between each pair of column lines and row lines. In the configuration shown in the drawing, the OLED is connected to the row line with its anode. The y drive element 314 drives the row line 308 at a constant current, and the x drive element 316 drives the column line 304 to selectively ground the column line. Both y drive element 314 and x drive element 316 are typically under the control of processor 318. Power supply 320 provides power to the circuitry, particularly to y drive component 314.

Several examples of OLED display drive elements are shown in US 6,014,119, US 6,201,520, US 6,332,661, EP 1,079,361 A and EP 1,091,339 A; OLED display drive element integrated circuits using PWM are from Krell, Beverly, MA (USA) Clare, Inc.) is sold by Clare Micronix. A number of examples of improved OLED display drive components are described in the applicant's co-pending applications WO 03/079322 and WO 03/091983. In particular, WO 03/079322, incorporated herein by reference, discloses a programmable current generator with digitally controlled control with improved compliance.

There is still a continuing need for techniques that can improve the lifetime of OLED display elements. There is a particular need for techniques that can be applied to passive matrix display elements because passive matrix display elements are far less expensive to manufacture than active matrix display elements. Reducing the driving level of the OLED (and thus the brightness) can significantly extend the lifetime of the OLED component, such as halving the driving level/brightness of the OLED to extend its lifetime to a factor of about four. The inventors have appreciated that multi-wire addressing techniques can be employed to reduce the peak display drive level, particularly for passive matrix OLED display elements, thereby extending the life of the drive elements.

Summary of invention

According to a first aspect of the present invention, there is provided a method of driving a light-emitting element, particularly a drive element, the display element comprising a plurality of pixels, each of which can be addressed by a column electrode and a row electrode, the method comprising: Driving the signal to drive the plurality of row electrodes; and driving the row electrodes with the row driving signals, driving the two or more of the columns of the electrodes with the first set of column driving signals; and then the second group (and the subsequent groups of the selective Driving a signal to drive a plurality of row electrodes; and driving the row electrodes with a second set (and optionally subsequent) row drive signals while driving the signals in a second set (and select subsequent sets) The two or more column electrodes are driven.

The specific example of the present invention allows a plurality of pixels of two or more columns of display elements to simultaneously emit light, thereby reducing the peak brightness of the OLED pixels of the display element, thus extending the life of the display element. In addition, power consumption is also reduced due to a decrease in driving voltage and a decrease in capacitance loss.

Broadly speaking, by driving multiple sets of columns and rows simultaneously, instead of sequentially driving columns and rows as in the conventional drive system, the interaction between the brightness of pixels between different columns can be utilized, thereby establishing columns in multiple line scan cycles. The (line) required illumination side is drawn instead of a single line scan period (but in the specific example, the same total number of line scan periods can be used, for example three lines for a total of three periods).

By establishing a light-emitting side map due to a plurality of line scan periods, the pixel drive level of each line scan period can be reduced. The degree of reduction is determined according to the interaction relationship between the plurality of sets of lines that are driven together, and is preferably selected in groups of two or more columns (lines) according to their interaction relationship or expected interaction relationship. For example, in a "Windows" (product name) type display element, a plurality of lines have an interactive relationship value; a pixel line constituting a character (for example, a diagonal stroke considering the letter "A") is also true.

In other configurations, the column electrodes that are grouped and simultaneously driven may include primary color sub-pixel electrodes of display elements having color pixels. Generally, there is a high degree of interaction between color pixels such as red, green, and blue sub-pixels because all of the red, green, and blue sub-pixels contribute to the overall brightness of the color pixel.

Preferably, the first and second row of driving signals and the first and second column of driving signals are selected such that the brightness determined by the first column and the row driving signal and the brightness determined by the second column and the row driving signal are substantially linear And the desired brightness of the OLED pixel (or sub-pixel) driven by the borrowed electrode and the row electrode. If three column electrodes are driven together, the method includes the steps of driving the column and row electrodes for the first, second, and third sets of column/row drive signals, respectively.

If a set of column drive signals contribute less to the total desired brightness of the borrowed electrode and row electrode driven OLED pixels, in other words, if a set of column/row drive signals contribute less to the aforementioned linear sum, then the contribution can be ignored. And delete the corresponding column/row driver steps. In this way, the total frame rate can be provided (since the total number of line scan cycles is reduced), thus increasing the brightness of the display elements of the (integrated) human eye, thus allowing for further degradation of the spike drive signal. This point can be taken into consideration when driving the aforementioned linear and decision column and row drive signals.

Similarly, when two or more columns of pixels have substantially the same desired brightness for most or all of the pixels in the columns, only a single common column drive signal needs to be applied, and two or more columns can be deleted. The second set of column and row drive signals also have the effect of increasing the frame rate, or similarly allowing the line period to be extended for the same overall frame rate.

Preferably, the first and second column and row drive signals comprise current drive signals because the OLED has a substantially linear response to such current drive, such that when two or more columns are driven together, it is helpful to determine the appropriate column drive. Signal and line drive signals. Such a current drive signal can be conveniently generated and provided by a (controllable) constant current, which can include a current source or current sink. Additionally or alternatively, the first and second column and row drive signals can include pulse width modulated drive signals; typically any variable that modifies the brightness of the OLED can be used to change the column/row drive level.

As explained above, in a specific example, the first and second column and row drive signals are selected such that the peak brightness of the driven pixel is less than the peak brightness of the column electrodes that are driven separately. The simultaneously driven pixel columns may be included in adjacent pixel lines on the display element, or may include multiple columns. Since the interaction relationship between them is relatively increased, the plurality of columns are grouped into groups of two, three or more. group. For example, where frequent dithering is used, a set of two or more alternating columns can be addressed simultaneously.

The principle can be extended to a video situation in which a plurality of columns in the time domain are grouped into groups, or in addition to extending into the airspace, in other words, the group of columns can include the same column of images displayed continuously, and in multiple consecutive frames. The box establishes the desired illuminating side.

Whether using pulse width modulation driving and/or variable current driving, using a set of column driving signals to drive two or more, driving a pair of column driving signals with one column driving signal and simultaneously driving a group of row electrodes The row drive levels are divided between the columns according to the ratio defined by the column drive signals. In other words, the ratio of the drive signals applied to the columns can determine the proportion of the common row drive signals received by the columns.

In the foregoing method, it is necessary to understand that the column drive signal and the row drive signal role are interchangeable. Specific examples of the method are particularly useful for passive matrix type display elements, but can also be used for active matrix type display elements.

The invention also provides an emissive type, particularly an OLED display drive element, which comprises means for making a specific example of the foregoing method. Such means include separate components and/or one or more integrated circuits, or ASIC (Special Application Integrated Circuit) or FPGA (Field Programmable Gate Array) or with appropriate processor control code (or micro A dedicated processor of code) or a combination thereof.

Thus, the present invention also provides an emission type for driving an emission display element, particularly an OLED display driving element, the emission display element comprising a plurality of pixels, each of which can be addressed by a column electrode and a row electrode, the display driving element comprising: a means for driving a plurality of row electrodes by a row driving signal; and means for driving the two or more column electrodes by the first group of column driving signals while driving the row electrodes with the first row driving signals; driving by the second group of rows a means for driving a plurality of row electrodes; and means for driving the two or more columns of electrodes with the second set of column drive signals while driving the row electrodes with the second row of drive signals.

The invention further provides an emission type, in particular an OLED display element, of an emission type, in particular an OLED display driving circuit, the pixel (OLED) of the display element being addressable by a column electrode and a corresponding row electrode, the display driving element comprising: one or more rows Driving the element to simultaneously drive the plurality of row electrodes; and one or more columns of driving elements to drive the plurality of column electrodes corresponding to the row electrodes simultaneously with the driving of the row electrodes, so that the driving elements of the row electrodes are driven by the plurality of column driving elements Shared between.

Preferred column drive elements and row drive elements comprise substantially constant current generators (current sources or current sinks); these can be controlled or planned using digital to analog converters.

The present invention further provides a processor control code and a carrier medium carrying the code to implement the foregoing method and display drive component. The code may comprise a conventional code, such as for a digital signal processor (DSP); or a code containing microcode, or a code that sets or controls an ASIC or FPGA, or a hardware description language such as VeriLog (trade name); The equal code can be spread across multiple coupling elements. The carrier medium may comprise a conventional storage medium such as a disc or a planned memory such as a firmware, or a data carrier such as an optical or electrical signal carrier.

In another aspect, the present invention provides an integrated circuit die wafer comprising a plurality of driving elements assembled to simultaneously drive a plurality of electrodes of an OLED display element, the display element driving processing circuit being configured to determine a driving signal for the plurality of electrodes; And wherein the grains have an aspect ratio greater than 10:1 (length: width), preferably greater than 15:1.

The inventors have appreciated that display element drive processing circuitry can be incorporated into conventional drive component wafers with little or no increase in occupied silicon wafer area. The reason is that the driver wafers are typically physically assembled into a long line of substantially identical drivers, but because there is very little physical width that allows the wafer to be diced, there is often a substantial amount of substantially unused dead space. For example, the drive element wafer has a die length of 20 mm and a minimum width of about 1 mm. The inventors have learned that the physical assembly structure using such a thin and long drive element chip can effectively utilize the space to implement processing circuitry to aid in the performance of the specific method of the foregoing method.

In particular, as will be described hereinafter, preferred embodiments of the method can be implemented using calculations involving matrix calculations. Such matrix calculations can be performed in a manner well known to those skilled in the art using one or both edges of the integrated circuit die of the drive element, using conventional signal processing blocks from a suitable repository known as "Intellectual Property". For example, if the required additional wafer area does not exceed the available "invalid space", there is little or no impact on wafer manufacturing costs. It is more preferable to limit the specific example of the method to 2 to 4 while driving the column, or to drive the column without more than 6 at the same time.

The colorful display elements according to the present invention can also be provided via the use of white-emitting sub-pixels with color filters attached thereto.

The present invention also provides a colorful organic electroluminescent display element comprising a pixel matrix, each pixel having at least three sub-pixels, wherein the first sub-pixel comprises a first color sub-pixel, the second sub-pixel comprises a second color sub-pixel, and a third The sub-pixels include a third color sub-pixel that overlaps the first color and the second color, or a color mixture that includes the first color and the second color, and an optional additional color.

Preferably, the third sub-pixel includes sub-pixels that are integrated to emit light within the first sub-pixel and the second sub-pixel domain. A fourth sub-pixel of a fourth color (eg, a mixed color of the first, second, and third colors, and an optional additional color) may also be included. The third sub-pixel may include white light sub-pixels, and/or may be configured to emit light belonging to the first, second, and fourth sub-pixel ranges (in other words, the third sub-pixel may have overlapping first color, second color And the color of the fourth color, and/or the third sub-pixel is emitted at a wavelength overlapping the emission wavelengths of the first, second, and fourth sub-pixels). All of the sub-pixels have substantially the same area, or the third sub-pixel may have a larger area than the other sub-pixels.

The present invention further provides a method for providing a colorful organic electroluminescent display element having a long lifetime, the display element comprising a matrix of pixels, each pixel having at least three sub-pixels, wherein the first sub-pixel comprises a first color sub-pixel, the second sub-pixel The pixel includes a second color sub-pixel, and the third sub-pixel includes a third color sub-pixel overlapping the first color and the second color, or a mixed color including the first color and the second color and the optional additional color, the method includes Determining a light output of the third sub-pixel as a light output component of the first sub-pixel and a light output component of the second sub-pixel; determining a maximum portion of the light output that can be emitted by using the third sub-pixel for a specified color; The light output of the first sub-pixel and the light output of the second sub-pixel are subtracted from corresponding light output components.

By combining the respective color pixels of the additional color sub-pixels, the specific examples of the foregoing display elements and methods allow for a combination of improved life, gamut widening, and reduced power consumption. In particular, in combination with white pixels, the need for blue pixels (the shortest lifetime) can be significantly reduced when the white background is mainly displayed. This helps to extend the life of the display element because the white-emitting OLED has a substantially longer lifetime than a blue OLED having an equal light output that produces the same white light. In a specific example, combining other colors such as 靛, violet, and/or yellow sub-pixels allows access to a wider color gamut area. This point is preferred for use with, for example, special display elements employed by the graphic arts community.

Simple illustration

These and other aspects of the invention will be further illustrated by the following examples with reference to the accompanying drawings in which Figures 1a and 1b show a longitudinal section of an OLED device and a simplified cross-sectional view of a passive matrix OLED display element, respectively; The figure shows the driving configuration of the passive matrix OLED display element in concept; the third figure shows the block diagram of the known passive matrix OLED display driving component; the 4a to 4c diagrams respectively show the implementation of the MLA addressing system for the color OLED display element. A block diagram showing a first example and a second example of a driving element hardware, and a time-history diagram of such a system; FIGS. 5a to 5g respectively show display driving elements embodying aspects of the present invention; display driving of FIG. 5a Array of drive elements and row drive elements, digital to analog current converter examples; programmable current mirrors embodying one aspect of the present invention; second programmable current mirrors embodying one aspect of the present invention; and prior art Block diagram of the current mirror; Figure 6 shows the layout of the integrated circuit die of the signal processing circuit and the driving component circuit combined with the multi-line addressing; Schematic diagram of the pulse width modulation MLA drive system; Figures 8a to 8d respectively show the columns, rows and image matrices of the conventional drive system and the multi-line addressing drive system, and the corresponding brightness curves of typical pixels in a frame period Figure 9a and 9b show the SVD factorization and NMF factorization of the image matrix, respectively; Figure 10 shows the row and column drive configuration examples using the matrix display of the matrix of Figure 9; Figure 11 shows the use of image matrix factorization. A flowchart of a method of driving a driving element; and FIG. 12 shows an example of a display image obtained by factoring an image matrix.

Detailed description of the preferred embodiment

Consider a pair of columns of passive matrix OLED display elements comprising a first column A and a second column B. In the conventional passive matrix drive system, the columns are driven as shown in Table 1 below, and each column is in the all-on state (1.0) or the full-off state (0.0).

Consider the ratio A / (A + B); in the example of Table 1, the ratio is zero or 1, but assuming that the pixels of the same row of the two columns are not completely on in the two columns, the ratio is decreased, but still available The desired pixel brightness. This way, the peak drive level can be reduced and the pixel life can be extended.

On the first line scan, the brightness is: first period 0.0 0.361 0.650 0.954 0.0 0.0 0.015 0.027 0.039 0.0 second period 0.2 0.139 0.050 0.046 0.0 0.7 0.485 0.173 0.161 0.0

It can be seen that: 1. The ratio of the two columns is equal in a single scanning period (the first scanning period is 0.96, and the second scanning period is 0.22).

2. The brightness of the two columns is added to the required value.

3. The peak brightness is equal to or less than the brightness during the standard scan.

The foregoing example verifies the technique of a simple second-line case. If the brightness data ratio between the two lines is similar, a higher effect can be obtained. Depending on the type of calculation of the image data, the brightness can be reduced by an average of 30% or more, which can have a significant beneficial effect on the lifetime of the pixel. Expanding the technology while considering more columns can provide even greater results.

Examples of multi-line addressing using SVD image matrix decomposition are listed below.

The inventors describe the drive system as matrix multiplication, where I is the image matrix (bit map file), D is the displayed image (which must be equal to I), R is the column drive matrix and C is the row drive matrix. Each row of R is described as the drive level of the column in the "line period", and each column or R represents the driven column. One column in the time system is the identity matrix. The board display for 6x4 display components: D(R, C):=R. C C:=1

- The same as the image.

Now consider using the two-frame drive method:

Again this is the same as the image matrix.

The drive matrix can be calculated using a single-valued decomposition as follows (named after using MathCad): X:=svd(I ^T ) (obtaining U and V) Y:svds(I ^T ) (obtaining S as a diagonal component) Vector) Note that Y has only two elements, and two frames: U:=submatrix (X,0,5,0,3) (ie, the last 6 columns)

V:=submatrix (X,6,9,0,3) (ie the next 4 columns)

W:diag(Y) (that is, the format Y is used as a diagonal matrix)

D:=(U.W.V) ^T check D:

R:=(W.V) ^T (note the last 2 lines of the blank)

R: submatrix (R, 0, 3, 0, 1) (select non-blank lines)

C:=U ^T (Reducing R, let C only drop to the top)

C: submatrix (C, 0, 1, 0, 5)

It is the same as the desired image.

Now consider the more general case, the image of the letter "A": X:=svd(I ^T )Y:=svds(I ^T )(Note that Y has only two elements, that is, only three frames)

U: submatrix (X, 0, 5, 0, 3) V: submatrix (X, 6, 9, 0, 3) (check D)

R:=(W.V) ^T (note the last line of the blank).

R: submatrix (R, 0, 3, 0, 2) C:=U ^T (Reduced R, let C only drop to the top).

C:=submatrix (C,0,2,0,5)

It is the same as the desired image.

In this case, R and C have negative numbers, which is undesirable for driving passive matrix OLED display elements. According to the inspection, positive factorization can be performed:

Non-negative matrix factorization (NMF) is obtained in a general way to achieve this project. For non-negative matrix factorization, the image matrix I is factorized into: I=W.H (Equation 3)

A number of NMF techniques are described in the following references, which are incorporated herein by reference: DDLee, HS Seung. Algorithms for non-negative matrix factorization; P. Paatero, U.Tapper.Least squares formulation of robust non-negative factor analysis .Chemometr.Intell.Lab. 37 (1997), 23-35; P. Paatero. A weighted non-negative least squares algorithm for three-way 'PARAFAC' factor analysis. Chemometr. Intell. Lab. 38 (1997), 223 -242;P.Paatero,PKHopke,etc.Understanding and controlling rotations in factor analytic models.Chemometr.Intell.Lab.60(2002),253-264;JWDemmel.Applied numerical linear algebra.Society for Industrial and Applied Mathematics,Philadelphia .1997;S.Juntto,P.Paatero.Analysis of daily precipitation data by positive matrix factorization.Environmetrics,5(1994),127-144;P.Paatero,U.Tapper.Positive matrix factorization:a non-negative factor model With optimal utilization of error estimates of data values. Environmetrics, 5 (1994), 111-126; CLLawson, RJ Hanson. Saving for least squares pro blems.Prentice-Hall, Englewood Cliffs, NJ, 1974; Algorithms for Non-negative Matrix Factorization, Daniel D. Lee, H. Sebastian Seung, pages 556-562, Advances in Neural Information Processing Systems 13, Papers from Neural Information Processing Systems (NIPS) 2000, Denver, CO, USA. MIT Press 2001; and Existing and New Algorithms for Non-negative Matrix Factorization By Wenguo Liu & Jianliang Yi ( www.dcfl.gov/DCCI/rdwg/nmf.pdf ; The source code of the deductive rule can be found at http://www.cs.utexas.edu/users/liuwg/383CProject/CS_383C_Project.htm).

The NMF factorization procedure is illustrated in Figure 9b.

Once the aforementioned basic system has been implemented, other techniques can be used to obtain additional effects such as repeated column pixels (not uncommon for Windows (trade name) type applications) can be written simultaneously to reduce the number of line cycles, thus shortening the frame period Also reduces the peak brightness required for the same integrated brightness. Once the SVD decomposition has been obtained, only the lower columns of the smaller (drive) values can be ignored because of the reduced impact on the final image quality. As explained above, the aforementioned multi-line addressing technique can be applied to a single display frame, but the illumination side of one or more columns can be established in addition to the spatial dimension. Via moving image compression technology, it is helpful to use time interpolation between frames.

Specific examples of the aforementioned MLA technology are particularly applicable to color OLED display elements. In this case, the technique is preferably applied to red (R), green (G), and blue (B) sub-pixel groups, and is also selectively used. Between pixel columns. The reason is that the image is expected to contain similar color blocks, and the reason is that the interaction between the R, G, and B sub-pixel driving elements is often higher than the separation between the individual pixels. Thus, in the specific example of the system, the multi-line addressing columns are grouped into R columns, G columns, and B columns, and the three columns define one complete pixel, and the images can be stacked by simultaneously selecting combinations of R, G, and B columns. For example, if the large area of the image to be displayed is white, the image can be stacked by first selecting the R, G, and B column groups together while applying appropriate signals to the column driving elements.

The use of color display elements of the MLA system has the added advantage. In the conventional color OLED display device, a column of pixels has the pattern "RGBRGB....", so when the column functions, the separate row driving elements simultaneously drive the R, G, and B sub-pixels to provide full-color pixels. . However, the three columns can have the configurations "RRRR....", "GGGG.....", "BBBB.....", and the single row addresses the R, G, and B sub-pixels. This configuration simplifies the application of OLED display elements, such as a column of red pixels that can be (inkjet) printed in a single long slot (separated from adjacent slots by a cathode spacer) rather than defining the three different colored materials for each column. Separate "well". This eliminates the manufacturing steps and also increases the pixel aperture ratio (ie, the percentage of the display area occupied by the active pixels). In yet another aspect, the present invention provides a display element of this type.

Figure 4a shows a block diagram of an example of a display component/drive component hardware configuration 400 for such a system. As can be seen, the single row driver 402 can address the red 404, green 406, and blue 408 pixel columns. The permutation permutations of the red, green, and blue columns can be addressed using column selector/multiplexer 410, or otherwise addressed using current sinks that control the columns as explained below. It can be seen from Figure 4a that this configuration allows red, green, and blue sub-pixels to be printed on linear grooves (rather than wells) that each share a common electrode. This reduces the complexity of the substrate patterning and printing, and increases the aperture ratio (and thus indirectly extends life by reducing the number of drives required). Using the physical components of Figure 4a, a number of different MLA drive systems can be implemented.

In the first example driving system, an image is created by sequentially addressing multiple sets of columns, as follows: 1. White components: R, G, and B are selected and driven together 2. Red + blue common drive 3. Blue + green Common drive 4. Red + green common drive 5. Only red 6. Only blue 7. Only green

With a minimum number of color combinations, only the desired color steps are performed to stack the images. Depending on the application needs, the combination can be optimized to extend life and/or reduce power consumption.

In another color MLA system, the driving of the RGB columns is divided into three line scan periods, each of which drives a primary color. The primary colors form a color gamut from the selected combination of R, G, and B. The color gamut contains all of the desired colors along the display line or display column: in one method, the primary colors are R+aG=aB, G+bR+bB, B+cR+cG where 0 >=a,b,c>=1, a, b, and c are selected as the maximum possible values (a+b+c=maximum), while still including all desired colors within their gamut.

In another method, a, b, and c are selected in a system to optimize the overall performance of the display element. For example, if the lifetime of blue is the limiting factor, then a and b can be maximized by sacrificing c; if the power consumed by red is a problem, then b and c can be maximized. The reason is that the total emission brightness is equal to a fixed value. Consider the example of b=c=0. In this case, red brightness must be fully achieved in the first scan cycle. However, if b and c>0, the red brightness is gradually established in a plurality of scanning periods, thereby reducing the peak brightness, prolonging the life of the red sub-pixel and improving the efficiency of the red sub-pixel.

In another variation, the time of individual scan cycles can be adjusted to optimize lifetime or power consumption (eg, to provide extended scan periods).

In yet another variation, the primary colors can be arbitrarily selected, but define the smallest possible color gamut while still including all of the colors on a line of the display element. For example, in extreme cases, there is only a green tint in the reproducible color gamut.

Figure 4b shows a second example of a display drive component hardware 450, wherein the same components as in Figure 4a are labeled with the same reference numerals. In Figure 4b, the display element includes an additional plurality of columns of white (W) pixels 412 that are also used to create a color image when the combined three primary colors are driven.

Broadly speaking, the inclusion of white sub-pixels reduces the need for blue pixels, thereby extending the life of the display elements; in addition, depending on the drive architecture, the power consumption of the specified color display elements can be reduced. Colors other than white may also include sub-pixels such as violet, bluon, and/or yellow-emitting photons, for example, to expand the color gamut. Subpixels of different colors do not need to have the same area.

As shown in Figure 4b, each column contains a monochrome sub-pixel as shown in Figure 4a, but it should be understood that conventional pixel layouts can also be used with successive R, G, B, and W pixels along each column. . In this case, each row will be driven by four separate row drive elements, one for each of the four colors.

It shall be understood that the aforementioned multi-line addressing system may be combined with the configuration of the display element/drive element of FIG. 4b, and the combinations of the columns of R, G, B and W are addressed in different permutation arrangements and/or addressed with different drive ratios. That is, use a column multiplexer (as shown) or use current sink addressing for each line. As explained above, the image is created by continuously driving a combination of different columns.

As described in the foregoing summary and as described in detail below, several preferred driving techniques employ variable current drive for OLED display pixels. However, for a relatively simple drive system that does not require a current mirror, one or more column selectors/multiplexers can be used to implement the display by a single selection and combination according to the color display drive architecture of the first example shown above. Component column.

Figure 4c shows the time course of the selection of such a system. In the first cycle 460, the white, red, green, and blue columns are selected and driven together; in the second cycle 470, only the white columns are driven, and in the third cycle 480, only the red columns are driven, all according to the pulse width adjustment. Variable drive timing.

Referring next to Figure 5a, there is shown a schematic diagram of a specific example of a passive matrix OLED drive component 500 implemented as an MLA addressing system as previously described.

In Fig. 5a, the passive matrix OLED display element similar to that described above with reference to Fig. 3 has a column electrode 306 driven by column drive circuit 512 and a row electrode 310 driven by row drive element 510. Details of the column drive elements and row drive elements are shown in Figure 5b. The row driving element 510 has a row data input 509 for setting current driving for one or more of the row electrodes. Similarly, the column driving component 512 has a column data input 511 for setting the current driving ratio for two or more columns. For ease of interfacing, preferred inputs 509 and 511 are digital inputs; preferred row data input 509 is current driven for all m rows of display elements 302.

The display data is provided in the data and control bus 502, and the bus bars can be connected in series or in parallel. The bus bar 502 provides an input to the frame storage memory 503, which stores brightness data for each pixel of the display element; or stores the brightness information of each sub-pixel in the color display element (can be encoded as a separate RGB color signal, or encoded as Luminance signal or chroma signal, or encoded in several other ways). The data stored in the frame memory 503 determines the desired brightness of each pixel (or sub-pixel) of the display element, and the information can be read by the display driver processor 506 using the second read bus 505 (specifically In the example, bus bar 505 can be deleted, or bus bar 502 can be used instead.

The display driver processor 506 can be implemented entirely in hardware, or implemented in software, for example using a digital signal processing core, or a combination of both, for example, using dedicated hardware to speed up the operation of the matrix. However, display driver processor 506 typically operates at least in part using code or microcode stored in program memory 507, operates under control of clock 508, and operates in conjunction with working memory 504. The code of the program memory 507 can be provided to a data carrier or a removable storage device 507a.

The code of the program memory 507 is assembled to implement one or more of the aforementioned multi-line addressing methods using conventional programming techniques. In a number of specific examples, such methods can be implemented using standard digital signal processors and codes executed in any conventional programming language. In this case, a conventional DSP routine library can be used to implement single-value decomposition; or a dedicated code can be written for use in the project; or other specific examples of non-SVD can be implemented, such as driving in the foregoing. Color display element described techniques.

Referring now to Figure 5b, the details of row drive element 510 and column drive element 512 of Figure 5a are shown. Row driver circuit 510 includes a plurality of controllable reference current sources 516, each having a current source, each under individual control of analog to analog converter 514. The implementation details of these examples are shown in Figure 5c. From Figure 5C, the controllable current source 516 includes a pair of transistors 522, 524 coupled to the power line 518 in a current mirror configuration.

In this example, since the row driving elements include current sources, the current sources are PNP bipolar transistors connected to the positive power supply line; current sink NPN transistors are used to connect to ground; in other configurations, MOS transistors are used. The digital to analog converters 514 each include a plurality of (three in this example) FET switches 528, 530, 532 that are individually coupled to respective power supplies 534, 536, 538. Gate junctions 529, 531, 533 provide digital input switching individual power supplies to respective current setting resistors 540, 542, 544, each coupled to current input 526 of current mirror 516. The voltage supply of the power supply is doubled, and the second lowest power supply is twice the voltage minus the V _gs voltage drop, so the digital value on the FET gate connection is converted to the corresponding current on line 526; In addition, the power supply can have the same voltage and the resistors 540, 542, 544 can be expanded. Figure 5c also shows another D/A control current source/well 546; in this configuration, multiple transistors are shown, but a single larger size transistor can be used instead.

Column drive element 512 also incorporates two (or more) number controllable current sources 515, 517, which can be implemented using a configuration similar to that shown in Figure 5c, using a current sink instead of a current source mirror. In this manner, the controllable current sink 517 can be programmed to sink current at a predetermined ratio corresponding to the column drive level ratio. Thus, the controllable current sink 517 is coupled to a ratio control current mirror 550 having an input 552 for receiving a first reference current and an output for receiving (collecting) one or more (negative) output currents. Terminal 554, the output current to input current ratio is determined by the control input ratio defined by controllable current generator 517 based on the data on line 511. The two-column electrode multiplexers 556a, b are arranged to allow selection of one column of electrodes to provide a reference current, and to select another column of electrodes to provide an "output" current; other selectors/multiplexers 556b for selective use and currents can be provided The mirror output of mirror 550. As shown, column drive element 512 allows two columns of one column to be selected for simultaneous driving, but other alternative configurations may be used, for example, in one embodiment, from 64 columns of electrodes x 64 In the multiplexer, 12 columns (1 reference column and 11 current mirror) are selected; in another configuration, 64 columns are divided into a plurality of blocks, each having an associated column of drive elements, which can select multiple columns that are simultaneously driven.

Figure 5d shows the implementation details of the current mirror 550 of the planable ratio control of Figure 5b. In this embodiment, a bipolar current mirror having a so-called beta usage specification (Q5) is employed, but those skilled in the art will appreciate that a variety of other types of current mirror circuits can be used. In the circuit of Figure 5d, V1 is a typical power supply of about 3 volts, and I1 and I2 are defined by the current ratios of the collectors of Q1 and Q2. The current ratio of the second line 552, 554 is I1:I2, and the total line current thus specified is divided between the two selected columns by this ratio. Those skilled in the art will appreciate that the circuit can be expanded to any number of mirror currents via repeated implementations provided in the internal circuitry of the dashed line 558.

Figure 5e shows another specific example of a planable current mirror for the drive element 512 of Figure 5b. In another embodiment, each column is provided with a corresponding circuit of the internal circuit of the dotted line 558 of FIG. 5d, in other words, a current mirror output stage, and then one or more columns of selectors are selected for the selection of the current mirror output stages. One or more individually programmable reference current supplies (current sources or current sinks). Another selector selects one of the reference outputs to be used as a current mirror.

In the specific example of the column drive elements described above, the separate current mirror output can be set for each column of the complete display or for each column of the display element. If column selection is used, the columns can be grouped into blocks. For example, if a three-output current mirror is used to selectively couple to a set of 12 columns, then a set of three consecutive columns can be selected to provide the 12 columns. Three-line MLA. Other columns may be grouped using knowledge previously known about the images to be displayed, for example due to the nature of the displayed data (significant interactions between the columns), so that certain sub-segments of the image may benefit from the MLA.

The 5f and 5g diagrams respectively show the bottom reference potential and the positive supply reference potential, and the signs of the input current and the output current are displayed according to the prior art current mirror configuration. It can be seen that these currents have the same sign, but can be positive or negative.

Figure 6 shows a layout of the integrated circuit die 600 of the combination of the drive elements 512 of Figure 5a and the display drive processor 506. The die has an elongated rectangular shape, for example 20 mm x 1 mm in size, and the long line of the drive circuit with the first region 602 comprising substantially identical sets of components is used to implement the MLA display processing circuitry. Since there is very little physical width at which the wafer can be sliced, region 604 will become unused space.

The aforementioned MLA display driving elements employ variable current driving elements to control the brightness of the OLED, but those skilled in the art will appreciate that other driving means for changing the OLED pixels may be additionally or additionally employed, particularly PWM.

Figure 7 shows a schematic diagram of a pulse width modulation drive system for multi-line addressing. In Fig. 7, the row electrode 700 is provided with pulse width modulation driving elements on two or more columns of electrodes 702 to simultaneously achieve a desired brightness pattern. In the example of FIG. 7, by slowly migrating the second column pulse wave to a later time, the zero value shown can be smoothly changed to 0.5; the variable drive can be applied to the pixel usually by controlling the degree of overlap between the column pulse wave and the line pulse wave. .

Several preferred MLA methods using matrix factorization will now be described.

Referring to Figure 8a, a row R, row C, and an image I matrix of a conventional driver architecture that drives one column at a time are shown. Figure 8b shows the columns, rows and image matrices used in the multi-line addressing system. The typical pixels of the displayed image in Fig. 8c and Fig. 8d are displayed in a frame period pixel luminance or driving of the pixel, showing a reduction in peak pixel driving achieved by multi-line addressing.

Figure 9a graphically shows the single value composition (SVD) of the image matrix I according to the following equation:

The display element can be driven by any combination of U, S and V, for example, driving the column in the US drive column and driving the line in V; or Drive the column to .V drive line. Other related techniques, such as QR decomposition and LU decomposition, may also be employed. Suitable numerical techniques are described, for example, in "Calculation of Numerical Values: Scientific Computing Techniques", Cambridge University Press, 1992; a library of multiple code modulations also includes appropriate routines.

Figure 10 shows a similar column drive element and row drive element as described with reference to Figures 5b through 5e, and is suitable for driving the display element with a factorized image matrix. Row drive component 1000 includes a set of adjustable substantially constant current sources 1002 that are coupled together and are provided with a variable reference current I _{r e f} for setting the current to each row of electrodes. For each row derived from a column of the factor matrix, such as column p _{i of} matrix 9 of the ninth graph, such reference current is modulated by a different value pulse width. Column drive element 1010 includes a planable current mirror 1012 similar to that shown in Figure 5e, but preferably has one output for each column of display elements or one for each column of a block of simultaneously driven columns Output. The column drive signal is derived from a row of the factor matrix, such as a row p _i of the matrix W of Figure 9b.

Figure 11 is a flow chart showing an example program for displaying an image using a matrix factorization such as NMF, which can be stored in the program memory of the program memory 507 of the display driver processor 506 of Figure 5a.

In Fig. 11, the program first reads the frame image matrix I (step S1100), and then uses NMF to factor the image pixels into factor matrices W and H; or when SVD is used, the factor is decomposed into other factor matrices such as U, S. And V (step S1102). This factorization can be computed during the early frame display. The program then drives the display element with the p sub-frame at step 1104. Step 1106 shows the sub-frame driver.

The sub-frame program sets the W-line p _i →R to form the column vector R. By the arrangement of the driving elements and the scaling factor x in the figure of FIG. 10, the automatic scaling becomes 1, so that the total of the respective elements is 1 by the regularization R, and R←xR can be derived. Similarly, H is used, and column p _i → C forms a row vector C. Proportional scaling gives a maximum element value of 1, obtaining a scaling factor y, C←yC. Determine the frame scale factor f = , the reference current system borrows I _ref = Set, where I ₀ corresponds to the current required for full brightness in the scan line of the conventional time system, and the x factor and y factor compensate for the proportional scaling effect introduced by the drive configuration (use other drive configurations to remove One or both).

Thereafter, in step S1108, the display driving element described in FIG. 10 drives the respective rows of the display elements with C and the columns of the R-driven display elements to undergo a 1/p total frame time. Repeat for each sub-frame, and then output the sub-frame data of the next frame.

Fig. 12 shows an example of an image composed of a specific example of the foregoing method; the format corresponds to the format of Fig. 9b. The image of Figure 12 is defined by a 50x50 image matrix, which is shown using 15 sub-frames in this example (p=15). The number of sub-frames may be determined in advance or may vary depending on the nature of the image being displayed.

The image manipulation calculation to be performed is equivalent to the operation performed by a consumer electronic photographing apparatus such as a digital camera in terms of general characteristics, and thus the photographing apparatus can conveniently implement a specific example of the method.

In other embodiments, the method can be implemented in a dedicated integrated circuit, or in a gate array, or in a software implementation on a digital signal processor, or in combinations of the like.

The foregoing technology can be applied to display elements based on organic LEDs and inorganic LEDs. The TMA system is pulse width modulation line driving (time control) on one axis and current division ratio (current control) on the other axis. For inorganic LEDs, the voltage system is proportional to the derivation law current (so the voltage product is obtained from the sum of the logarithmic currents); but for OLEDs, the secondary current-voltage dependence. As a result, when the aforementioned technique is used to drive an OLED, it is important to employ PWM. The reason is that even with current control, there is a feature that defines the voltage required to span a pixel for a given current; when using current control alone, it is not possible to apply the correct voltage to each pixel of the sub-frame. Although the TMA system can operate correctly with the OLED, the reason is that each column is driven to achieve a predetermined current, and each row is driven by the PWM time, actually decoupling the row driver from the column driver, thereby allowing the voltage variable by providing two separate control variables. Decoupled from the current variable.

Referring again to the NMF factorization of the image matrix, a number of particularly good fast NMF matrix factorization techniques are described in the applicant's co-examination of the British patent application 0428191.1, filed on December 23, 2004, the entire contents of which are incorporated by reference. Here.

Several other optimization methods are as follows: Since the current is shared between the columns, if the current of one column increases, the currents of the other columns decrease, so it is better (but not necessary) to compensate the reference current and the sub-frame time scaling. For example, the sub-frame time can be adjusted to achieve the same brightness of the peak pixels of each sub-frame (which also reduces the worst case/spike brightness aging). In fact, this point is limited by the shortest selectable sub-frame time and is also limited by the maximum line drive current, but since the adjustment is only the second power, optimization is not a problem.

Later, the sub-frame is subjected to a progressive reduction correction, so that the overall size becomes smaller, and the early sub-frame changes. Using the PWM drive instead of having an "on" portion at the beginning of the PWM cycle, the peak current can be reduced by randomly dithering the PWM cycle start point. In the actual implementation of the straight-through, the off time is greater than 50%, and the "on" part is counted at the end of the available period, and a similar effect can be achieved with lower complexity. This reduces the peak column drive current by up to 50%.

Columns contain red (R), green (G), and blue (B) pixels (sub-pixels) (ie, RGB, RGB, RGB column patterns), which are applied to a column because each pixel (sub-pixel) has different characteristics. The specified voltage cannot achieve the exact desired drive current for each OLED pixel (sub-pixel) of different colors. Therefore, it is preferred to use an OLED display having columns of red, green, and blue pixels (sub-pixels) that are separately driveable (that is, multiple sets of three columns each having RRRR..., GGGG..., and BBBB...). element. The advantages of ease of manufacture for such a combination structure have been described above.

Specific examples of the present invention have been described with reference to display elements based on OLEDs. However, the techniques described herein are also applicable to other types of emissive display elements including, but not limited to, vacuum fluorescent display elements (VFD) and plasma display panels (PDP) and other types of electroluminescence. Display elements such as thick film and thin film (TFEL) electroluminescent display elements are typically, for example, iFire (RTM) display elements, large size inorganic display elements, and passive matrix driven display elements.

It will be apparent to those skilled in the art that a variety of other effective alternatives are readily apparent, but it is to be understood that the invention is not limited to the specific examples, and that the present invention is intended to cover the true scope and scope of the appended claims. All modifications within.

100. . . OLED element, organic electroluminescent element

102. . . Substrate

104. . . Anode layer

106. . . Hole transport layer

108. . . Electroluminescent layer, luminescent polymer layer

110. . . Cathode layer

111. . . Metal can

112. . . Row group

113. . . UV curable epoxy resin adhesive

118. . . battery

150. . . Passive matrix OLED display element

152. . . Pixel

154. . . Conductive wire, cathode connection

158. . . Anode wire, anode connection

200. . . Constant current generator

202. . . Power supply line

204. . . Line

206. . . Column line

208. . . Ground wire

210. . . Link, image link

212. . . Pixel

300. . . schematic diagram

302. . . OLED display element

304. . . Column line

306. . . Electrode contact

308. . . Line

310. . . Row electrode contact

314. . . y drive component

316. . . x drive component

318. . . processor

320. . . Power Supplier

400. . . Display component / drive component hardware configuration

402. . . Row drive component

404. . . Red pixel

406. . . Green pixel

408. . . Blue pixel

410. . . Column selector/multiplexer

412. . . White pixel

450. . . Display driver component hardware

460. . . First cycle

470. . . Second cycle

480. . . Third cycle

500. . . Passive matrix OLED display element

502. . . Data and control bus

503. . . Frame storage memory

504. . . Working memory

505. . . Second read bus

506. . . Display driver processor

507. . . Program memory

507a. . . Data carrier or mobile storage element

508. . . clock

509. . . Line data input

510. . . Row drive component

511. . . Column data input

512. . . Column drive component

514. . . Digital to analog converter

515, 517. . . Digitally controllable current source

516. . . Controllable reference current source, current mirror

517. . . Current sink, controllable current generator

518. . . power cable

522, 524. . . a pair of transistors

526. . . Current input

528, 530, 532. . . FET switch

529, 531, 533. . . Gate link

534, 536, 538. . . Power Supplier

540, 542, 544. . . Current setting resistor

546. . . D/A controlled power source/well

550. . . Current mirror

552, 554. . . Second line

552. . . Input

554. . . Output

556a. . . Column electrode multiplexer

556b. . . Selector/multiplexer

558. . . Internal circuit

600. . . Integrated circuit die

602. . . First district

604. . . Adjacent area

700. . . Row electrode

702. . . Column electrode

1000. . . Row drive component

1002. . . Constant current source

1010. . . Column drive component

1012. . . Planable current mirror

S1100-S1108. . . step

1a and 1b respectively show a longitudinal sectional view of an OLED device and a simplified cross-sectional view of a passive matrix OLED display element; FIG. 2 conceptually shows a driving configuration of a passive matrix OLED display element; and FIG. 3 shows a known passive matrix OLED display Block diagram of the driving elements; Figures 4a to 4c respectively show block diagrams of the first and second examples of the display driving element hardware for implementing the MLA addressing system for the color OLED display elements, and the time course of such a system Figure 5a to 5g respectively show display drive elements embodying aspects of the present invention; column drive elements and row drive elements of display drive elements of Figure 5a, examples of digital to analog current converters; A planable current mirror; a second programmable current mirror embodying an aspect of the present invention; and a block diagram of a current mirror according to the prior art; and a sixth diagram showing the signal processing circuit and the driving element circuit in combination with the multi-line addressing Layout of the integrated circuit die; Figure 7 shows a schematic illustration of the pulse width modulated MLA drive system; Figures 8a through 8d show the conventional drive system and more The column, row and image matrix of the address-driven system, and the corresponding luminance curves of typical pixels in a frame period; the 9th and 9b graphs respectively show the SVD factorization and NMF factorization of the image matrix; and the 10th figure shows the use of the ninth The matrix of the figure shows an example of the row and column drive configuration of the driving elements; the 11th figure shows a flow chart of the method of driving the driving elements using image matrix factorization; and the 12th figure shows an example of the display image obtained by factoring the image matrix.

302. . . OLED display element

304. . . Column line

306. . . Electrode contact

308. . . Line

310. . . Row electrode contact

500. . . Passive matrix OLED display element

502. . . Data and control bus

503. . . Frame storage memory

504. . . Working memory

505. . . Second read bus

506. . . Display driver processor

507. . . Program memory

507a. . . Data carrier or mobile storage element

508. . . clock

509. . . Line data input

510. . . Row drive component

511. . . Column data input

512. . . Column drive component

Claims (22)

A method of driving an emissive display, the display comprising a plurality of pixels, each of which can be addressed by a column of electrodes and a row of electrodes, the method comprising: driving a plurality of the row electrodes with a first set of row driving signals; and using While the row driving signals drive the row electrodes, the first group of column driving signals biased in the forward direction are driven to drive the two or more column electrodes; and then the second group of row driving signals are used to drive the plurality of column electrodes a row electrode; and a second set of column drive signals biased in a forward bias to drive the two or more column electrodes while using the second set of row drive signals to drive the row electrodes; Selecting the first and second sets of row drive signals and the first and second sets of column drive signals for correlation or expected correlation between the columns of image data; One of the control of the set of column drive signals can control the ratio to distribute the first set of row drive signals between the column electrodes of the first set, and controllable ratio according to one of the control signals controlled by the second set of columns Allocating the second set of row drive signals between the columns of the second set of electrodes; the method further comprising driving the first column electrodes and the second column electrodes using a controllable current divider, a first set of column drive signals for distributing the first set of row current drive signals between the column electrodes of the first group, and Distributing the second set of row current drive signals between the column electrodes of the second group; wherein the first and second sets of row drive signals and the first and second sets of column drive signals comprise current drive signals And wherein the pixels are OLED pixels, and the first and second sets of row drive signals and the first and second sets of column drive signals are selected such that the first set of columns and rows are driven The brightness determined by the signal and the substantial linearity of the brightness determined by the second set of column and row drive signals obtains a desired brightness of the OIED pixel driven by the column and row electrodes to thereby A brightness appearance of one of the columns is established during multiple column scan cycles. The method of claim 1, wherein the first and second sets of row driving signals and the first and second sets of column driving signals are selected to be driven by the column electrodes and the row electrodes The peak brightness is lower than the peak brightness when the column electrodes are driven separately. The method of claim 1 or 2, further comprising the pixels having two or more columns having substantially the same desired brightness, omitting the second group of column driving signals and the second group of row driving The drive of the signal. The method of claim 1 or 2, wherein the two or more column electrodes drive the pixels of adjacent columns. The method of claim 1 or 2, wherein the two or more columns of electrodes drive the pixels of the separate columns or the columns of the interleaved columns. For example, the method of claim 1 or 2, wherein the two or more The electrodes are replaced by one or more column electrodes in two or more consecutive image frames displayed on the emissive display. The method of claim 1 or 2, further comprising omitting driving of the two or more column electrodes when substantially all of the second set of column drive signals are below a critical drive value. The method of claim 1 or 2, wherein the first and second sets of column drive signals and the first and second sets of row drive signals comprise pulse width modulated drive signals. The method of claim 1 or 2, wherein the first set of column and row drive signals and the second set of column and row drive signals comprise current drive signals. The method of claim 1 or 2, wherein each of the pixels comprises at least two sub-pixels of at least two different colors, each of the sub-pixels being addressable by the column electrodes and the row electrodes; and wherein the two or more The driving of the column electrodes includes column electrodes of two or more sub-pixels that drive a common pixel. The method of claim 1 or 2, wherein each of the pixels comprises at least two sub-pixels of at least two different colors, each of the sub-pixels being addressable by the column electrode and the row electrode; and wherein the two or more The column electrode drive includes column electrodes that drive sub-pixels of the same color. The method of claim 1 or 2, further comprising selecting the two or more column electrodes from a group of three or more adjacent column electrodes. The method of claim 1 or 2, wherein the column electrode driving package Having the first and second sets of column drive signals driving three or more of the column electrodes, the method further comprising driving the plurality of row electrodes with a third set of row drive signals, and The set of column drive signals drive the three or more column electrodes substantially simultaneously. The method of claim 1 or 2, wherein the emissive display is an OLED display. The method of claim 1, wherein the selecting step based on the correlation or the expected correlation is performed using a non-negative matrix factorization. A method of driving an emissive display according to claim 1 of the patent application, further comprising a first method of providing a colorful organic electroluminescent display having an increased lifetime, the display comprising a matrix of pixels, each pixel having at least three sub-pixels, wherein The first sub-pixel includes a first color sub-pixel, the second sub-pixel includes a second color sub-pixel, and the third sub-pixel includes a third color sub-pixel that overlaps the first color and the second color, the first method includes Determining a light output of the third sub-pixel as a light output component of the first sub-pixel and a light output component of the second sub-pixel; determining a maximum portion of a light output that can be emitted by using the third sub-pixel for a specified color And subtracting the corresponding light output component from the light output of the first sub-pixel and the light output of the second sub-pixel. A computer-accessible carrier carrying a processor control code that, when executed, implements the method of claim 1 or 2. An OLED display driver comprising means for implementing the method of claim 1 or 2. An emissive display driver for driving an emissive display, the emissive display comprising a plurality of OLED pixels, each pixel being addressable by a column of electrodes and a row of electrodes, the display driver comprising: a driving signal for using the first group of rows a means for driving a plurality of the row electrodes; for driving the row electrodes with the first set of row drive signals while driving the first set of column signals in a forward biased manner Two or more members of the column electrodes; means for driving the plurality of row electrodes using the second set of row drive signals; and for driving the row electrodes using the second set of row drive signals, Driving a second set of two or more of the columns of the second set of column drive signals in a forward biased manner; for selecting based on correlation or expected correlation between the columns of image data Column electrodes of the second or more column electrodes of the first group, and for selecting columns among the column electrodes of the second group based on correlation or expected correlation between the columns of image data a member of the electrode; and for assigning the first set of row drive signals between the first set of column electrodes according to a controllable ratio controlled by the first set of column drive signals, and One of the controls of the set of column drive signals can control the ratio to distribute the second set of row drive signals between the electrodes of the second set of columns; wherein the component for selecting is used to select the first and the first The two rows of driving signals and the first and second sets of column electrodes, such that the brightness determined by the first set of column and row driving signals and the brightness determined by the second column and row driving signals are substantially Linearly arranging a desired brightness of the OLED pixel driven by the column and row electrodes to thereby establish a brightness appearance of the column during a plurality of column scan periods; wherein the first and second groups The row driving signals and the first and second sets of column driving signals are current driving signals; and the emission display driver includes driving the first column electrodes and the second column electrodes using a controllable current distributor The component is configured to distribute the first row current driving signal between the column electrodes of the first group according to the first group column driving signal, and to the second group according to the second group column driving signal The second row of current drive signals are distributed between the column electrodes. The emissive display driver of claim 19, wherein the column driver and the row driver comprise circuitry for providing a substantially constant current that can be controlled. The emissive display driver of claim 19 is for driving an emissive display, wherein pixels of the display are addressable by column electrodes and corresponding row electrodes, the display driver comprising: one or more rows of drivers to simultaneously drive the plurality of The row electrodes; and one or more columns of drivers to drive a plurality of the column electrodes corresponding to the row electrodes simultaneously with the driving of the row electrodes, so that the driving system for the row electrodes is composed of a plurality of the column drivers Shared between. The emissive display driver of any one of claims 19 to 21, wherein the emissive display is an OLED display.