CN105845083B

CN105845083B - The system and method for compensation for the inhomogeneities in light emitting device display

Info

Publication number: CN105845083B
Application number: CN201610341925.1A
Authority: CN
Inventors: A·内森; G·查吉; S·亚历山大; P·塞尔瓦蒂; R·I-H·黄; C·丘尔奇
Original assignee: Ignis Innovation Inc
Current assignee: Ignis Innovation Inc
Priority date: 2010-11-15
Filing date: 2011-11-15
Publication date: 2018-09-04
Anticipated expiration: 2031-11-15
Also published as: EP2453433B1; EP2453433A3; EP2453433A2; CN102663976A; CN102663976B; CN105845083A

Abstract

The present invention relates to the system and method for the compensation for the inhomogeneities in light emitting device display.Provide a kind of system and method for operating display some pixels in the display are over time and when degenerating with constant luminance.Each pixel in the display is configured as emitting light when supplying voltage to the driving circuit of pixel, which makes electric current flowing pass through light-emitting component.The pixel of degeneration is compensated by supplying the voltage of bigger for their own driving circuit.The display data is scaled by the compressibility factor less than 1, to retain the pixel that some voltage class are degenerated for compensation.When becoming more to degenerate in pixel and requiring additional compensation, reduce the compressibility factor so as to retention outside voltage class for compensation.

Description

The system and method for compensation for the inhomogeneities in light emitting device display

It is on November 15th, 2011, application No. is 201110463190.7 that the application, which is the applying date, entitled " to be used for The divisional application of the system and method for the compensation of inhomogeneities in light emitting device display " application for a patent for invention.

Technical field

The present invention relates to display technology, the inhomogeneities to the element in light emitting device display is more particularly related to The system and method compensated.

Background technology

Active matrix organic light-emitting diode (AMOLED) display is well known technology.For example, low due to non-crystalline silicon Cost and the foundation structure largely installed manufactured from Thin Film Transistor-LCD (TFTLCD) (infrastructure), therefore non-crystalline silicon is a kind of promising material for displayer.

All displayers all show the difference of brightness no matter what backplane technology used between each pixel It is different, this primarily as processing or structure it is unbalanced as a result, either due to being drawn over time by operating with The aging risen.The inhomogeneities of brightness in the display be also likely to be by from OLED material itself chemistry and performance from Caused by right difference.These inhomogeneities must show electronic equipment to manage, so that display device reaches by AMOLED The commercial acceptable performance level used for mass market.

Fig. 1 shows the operating process of traditional displayer 10.With reference to figure 1, video source 12 includes each pixel Brightness data, and brightness data is sent to digital data processor 16 in the form of numerical data 14.Digital data processing Device 16 can execute some data processing functions, such as scaling (scale) resolution ratio or the color for changing display.At numerical data It manages device 16 and sends numerical data 18 to data driver integrated circuit (IC) 20.Data driver IC 20 is by the numerical data 18 Analog voltage or electric current 22 are converted to, the analog voltage or electric current 22 are sent to the thin film transistor (TFT) in pixel circuit 24 (TFT)26.The voltage or electric current 22 are converted to another electricity for flowing through Organic Light Emitting Diode (OLED) 30 by TFT 26 Stream 28.Electric current 28 is converted to visible light 36 by OLED 30.OLED 30 has OLED voltage 32, which is OLED two The voltage drop at end.It is the ratio of luminous quantity and the electric current by OLED that OLED 30, which also has efficiency 34, the efficiency 34,.

Numerical data 14, analog voltage/current 22, electric current 28 and visible light 36 all include that identical information is (i.e. bright Degrees of data).Their different-formats only from the original luminance data of video source 12.The desired operation of system is, to consider oneself as The brightness data of the given value of frequency source 12 always obtains the visible light 36 of identical value.

However, in the presence of several degeneration factors for the error that may cause on visible light 36.With lasting use, TFT pairs Lower electric current 28 will be exported in the identical input from data driver IC 20.With lasting use, OLED 30 is right The voltage 32 of bigger will be consumed in identical input current.Since TFT 26 is not perfect current source, this actually will Slightly reduce the electric current 28 of input.With lasting use, OLED 30 will lose efficiency 34, and identical electric current is sent out Penetrate less visible light.

It is visible over time even if sending identical brightness data from video source 12 due to these degeneration factors Light output 36 is also by smaller.According to the use of display, different pixels may have different amount of degradations.

Therefore, in the reality of the required brightness and pixel by some pixels specified by the brightness data in video source 12 There will be continuous increased errors between brightness.The result is that the image being reduced will not correctly be shown over the display.

A kind of mode for compensating these problems is to use feedback loop.Fig. 2 shows traditional AMOLED including feedback loop is aobvious Show the operating process of device 40.With reference to figure 2, photodetector 42 is used to directly measure visible light 36.Photodetector 42 is it will be seen that light 36 are converted to the signal 44 of measurement.The visible light signal 44 of measurement is converted to feedback signal 48 by signal adapter 46.Signal turns Parallel operation 46 can be analog-digital converter, digital analog converter, microcontroller, transistor or other circuits or device.Feedback letter Numbers 48 are used to along the certain point in its path (such as, between existing component (for example, 12,16,20,26,30), component Signal wire (for example, 14,18,22,28,36), or combinations thereof) at change brightness data.

It can require to some modifications of existing component and/or additional circuit, to allow based on from signal conversion The feedback signal 48 of device 46 changes brightness data.If visible light 36 is less than the desired brightness from video source 12, can To increase luminance signal, to compensate the degeneration of TFT 26 or OLED 30.This such that regardless of degenerate how visible light 36 all will be permanent It is fixed.This compensation scheme is commonly referred to as bulk of optical feedback (OFB).However, in the system of figure 2, photodetector 42 must be collected At on display, usually in each pixel and it is couple to pixel circuit.Do not consider photodetector is integrated into it is each When in pixel the problem of inevitable yield, it is desired to have the photodetector that itself do not degenerate, but realizes this light detection Device is that cost is high, and this photodetector is incompatible with the TFT-LCD manufacture infrastructures being currently installed on.

Accordingly, it is desirable to provide a kind of side that can compensate the inhomogeneities in display in the case where not measuring optical signal Method and system.

Displayer is operated according to the numerical data from video source.OLED in display It can be programmed to the light for the brightness that transmitting has according to program voltage or program current.Program current or program voltage are traditionally It is set by display driver, the display driver is using numerical data as input, and with for by program current Or program voltage is sent to the simulation output of pixel circuit.Pixel circuit is configured as electric current based on programming or program voltage to drive The dynamic electric current by OLED.

Invention content

It is an object of the present invention to provide a kind of method of at least one disadvantage eliminated or mitigate existing system and it is System.

According to an aspect of the present invention, it provides and a kind of is for compensate inhomogeneities in light emitting device display System, which includes multiple pixels and the source for pixel data to be provided to each pixel circuit.The system System includes：Module for changing the pixel data for being applied to one or more than one pixel circuit, for based on from the The measurement data that a part for one pixel circuit is read estimates the estimation module of the degeneration of first pixel circuit, Yi Jiyong In estimating come correct application in the institute of the first pixel circuit or the second pixel circuit for the degeneration based on first pixel circuit State the compensating module of pixel data.

According to another aspect of the present invention, a kind of compensate in the light emitting device display with multiple pixels not is provided The method of uniformity comprising following steps：Based on the measurement data read from a part for the first pixel circuit to estimate State the degeneration of the first pixel circuit, and the estimation of the degeneration based on the first pixel circuit come correct application in the first pixel circuit Or second pixel circuit pixel data.

Present disclose provides a kind of methods of the uniform luminosity (luminosity) of maintenance displayer.AMOLED Display includes the array of the pixel with luminescent device.Luminescent device be configured as according to the numeral input from video source and Emit light.Video source includes numerical data corresponding with the expectation brightness of each pixel in displayer.With when Between passage, aspect and their relevant driving circuit in luminescent device are degenerated, and require compensation so as to for given Numeral input continue transmitting with same brightness light.

By increasing the numeral input of the pixel according to the degeneration of the pixel measured or estimated, to compensate active display In pixel degeneration.In order to allow the generation of compensation, numeral input to be compressed to the value of the range less than usable range.According to Compressibility factor executes the compression to the numeral input, and the compressibility factor is the number less than 1.In the implementation of the disclosure, Numeral input is multiplied by compressibility factor, which is compressed to the numeral input range less than usable range.Digital model The remainder enclosed can be used for the degeneration of based on measurement or estimation pixel to provide the compensation to the pixel of degeneration.This The open method provided for setting and adjusting the compensation factor, so as to either statically or dynamically adjust the compensation because Son, and before signal is sent to the driving circuit, the compensation to display is provided by increasing the digital signal.

The detailed description of the various embodiments and/or aspect that are carried out in view of refer to the attached drawing, it will be appreciated by one of skill in the art that Next the above-mentioned and other aspect and embodiment of the present invention provide the Short Description of attached drawing.

Description of the drawings

According to the description of next refer to the attached drawing, these and other features of the invention will become more fully apparent.

Fig. 1 shows traditional AMOLED system.

Fig. 2 shows include photodetector and use traditional AMOLED of the feedback scheme of the signal from photodetector System.

Fig. 3 is shown using the dispalying systems for having the compensation scheme according to the embodiment of the present invention.

Fig. 4 shows the example of the dispalying systems of Fig. 3.

Fig. 5 shows the example of the pixel circuit of Fig. 5.

Fig. 6 shows another example of the dispalying systems of Fig. 3.

Fig. 7 shows the example of the pixel circuit of Fig. 6.

Fig. 8 shows the example of the module of the compensation scheme for the system applied to Fig. 4.

Fig. 9 shows the backoff algorithm module of Fig. 7 and the example of look-up table.

Figure 10 shows the example of inputs of the TFT to the conversion algorithm module of pixel circuit.

Figure 11 A show, the usage time that video source continues zero hour for the brightness data of each pixel the output phase etc. Experimental result.

Figure 11 B show that video source exports maximum luminance data to some pixels and exports zero luminance number to other pixels According to the experimental result for the usage time for continuing 1000 hours.

Figure 11 C are shown, when not applying backoff algorithm, maximum luminance data is received and other pictures in some pixels After element receives the usage time that zero luminance data continues 1000 hours, brightness of the video source for each pixel the output phase etc. The experimental result of data.

Figure 11 D show, in application constant luminance backoff algorithm, maximum luminance data is received and it in some pixels After its pixel receives the usage time that zero luminance data continues 1000 hours, video source is for each pixel the output phase etc. The experimental result of brightness data.

Figure 11 E show, when application reduces luminance compensation algorithm, maximum luminance data is received and it in some pixels After its pixel receives the usage time that zero luminance data continues 1000 hours, video source is for each pixel the output phase etc. The experimental result of brightness data.

Figure 12 shows the example of grayscale compression algorithm.

Figure 13 is the data flow of the compression and the compensation that show the luminosity input data for driving displayer Figure.

Figure 14 is to show the flow chart for requiring to select the method for compressibility factor according to display with the design of pixel circuit.

Figure 15 is to show to adjust distribution map (profile) according to scheduled headroom (headroom) to select compressibility factor Method flow chart.

Figure 16 is to show the dynamic measurement according to the degraded data more than the threshold value on first precompensation to select to press The flow chart of the method for the contracting factor.

Figure 17 be show according to dynamic measurements more than the degraded data of maximum value previously measured come select to compress because The flow chart of the method for son.

Although the present invention is vulnerable to various modifications and alternative form, specific embodiment passes through in the accompanying drawings Exemplary mode and show and will be described in detail in this application.It is to be appreciated, however, that the present invention is not intended to be limited to institute's public affairs The special shape opened.On the contrary, present invention covering is fallen into the spirit and scope of the present invention as defined by the appended claims All modifications, equivalents, and substitutions scheme.

Specific implementation mode

The embodiment of the present invention is described using including the displayer of the pixel circuit with TFT and OLED.But It is that the transistor in pixel circuit can use non-crystalline silicon, Nano micron crystal silicon, polysilicon, organic semiconductor technologies (example Such as, organic tft), NMOS technologies, CMOS technology (for example, MOSFET) or combinations thereof manufacture.Transistor can be p-type crystal Pipe or n-type transistor.Pixel circuit may include the luminescent device other than OLED.In the following description, " pixel " and " pixel circuit " uses in which can be interchanged.

Fig. 3 is shown using the operation for having the dispalying systems 100 according to the compensation scheme of the embodiment of the present invention.Video Source 102 includes the brightness data for each pixel, and brightness data is sent to numerical data in the form of numerical data 104 Processor 106.Digital data processor 106 can execute some data processing functions, such as scaling resolution ratio or change display Color.Numerical data 108 is sent to data driver IC 110 by digital data processor 106.Data driver IC 110 Numerical data 108 is converted into analog voltage or electric current 112.Analog voltage or electric current 112 are applied to pixel circuit 114.Picture Plain circuit 114 includes TFT and OLED.Pixel circuit 114 is based on analog voltage or electric current 112 exports visible light 126.

In figure 3, it has been shown as example a pixel circuit.But dispalying systems 100 include multiple pixels electricity Road.Video source 102 can be similar with the video source 12 of Fig. 1 and Fig. 2.Data driver IC 110 can be with the data of Fig. 1 and Fig. 2 Driver IC 20 is similar.

For display, compensation functions module 130 is set.Compensation functions module 130 includes for coming from pixel circuit 114 Measured value 132 (be referred to as the TFT and OLED of degraded data, the degraded data of measurement, the TFT degradation data of measurement or measurement Degraded data) execute algorithm (be referred to as TFT to pixel circuit transfer algorithm) module 134, and compensation functions module 130 Export calculated pixel circuit degradation data 136.Note that in the following description, using " TFT to pixel with can be interchanged The conversion algorithm module of circuit " and " transfer algorithm of TFT to pixel circuit ".

Degraded data 132 is to indicate that a part for pixel circuit 114 has been degenerated how many electric data.From pixel circuit 114 data measured can indicate, for example, one or more features of a part for pixel circuit 114.

It can be from for example one or more thin film transistor (TFT)s (TFT), Organic Light Emitting Diode (OLED) device or its group It closes to measure degraded data 132.Note that the transistor of pixel circuit 114 is not limited to TFT, and the photophore of pixel circuit 114 Part is not limited to OLED.The degraded data 132 measured can be number or the data of simulation.System 100 is based on coming from pixel The measured value of a part (for example, TFT) for circuit provides offset data, to compensate the inhomogeneities in display.It is uneven Even property may include irregularity in brightness, colour inhomogeneous or combinations thereof.The factor of these inhomogeneities is caused to may include But be not limited to, the processing or structure in display be unbalanced, pixel aging, etc..

Degraded data 132 can be measured at the timing of timing or the dynamic adjustment of rule.The pixel circuit degradation of calculating Data 136 can be the offset data for correcting inhomogeneities in the display.The pixel circuit degradation data 136 of calculating It may include any parameter for generating offset data.Can rule timing (for example, each frame, the interval of rule, etc. Deng) or dynamic adjustment timing at use offset data.The data of measurement, offset data or combinations thereof can be stored in storage In device (such as 142 of Fig. 8).

TFT to pixel circuit conversion algorithm module 134 or TFT to pixel circuit 134 sum number of conversion algorithm module Degraded data 132 of the combination of digital data processor 106 based on measurement estimates the degeneration of entire pixel circuit.Estimated based on this Meter, by digital data processor 106 adjust applied to certain pixel circuit brightness data (numerical data 104) come The entire degeneration of compensation pixel circuit 114.

The brightness data applied to the pixel circuit or non-degraded pixels circuit degenerated can be changed or be adjusted to system 100 104.For example, if the steady state value of visible light 126 is desired, the increase of digital data processor 106 is for high degradation The brightness data of pixel thereby compensates for degenerating.

In figure 3, the conversion algorithm module 134 of TFT to pixel circuit is provided separately with digital data processor 106. But the conversion algorithm module 134 of TFT to pixel circuit can be integrated into digital data processor 106.

Fig. 4 shows the example of the system 100 of Fig. 3.The pixel circuit 114 of Fig. 4 includes TFT 116 and OLED 120.Mould Quasi- voltage or electric current 112 are provided to TFT 116.The voltage or electric current 112 are converted to and flow through OLED 120 by TFT 116 Another electric current 118.Electric current 118 is converted to visible light 126 by OLED 120.OLED 120 has OLED voltage 122, should OLED voltage 122 is the voltage drop at the both ends OLED.OLED 120 also has efficiency 134, which is luminous quantity and pass through The ratio of the electric current of OLED 120.

The system 100 of Fig. 4 only measures the degeneration of TFT.The degeneration of TFT 116 and OLED 120 be with use it is relevant, And TFT 116 and OLED 120 are always concatenated (link) in pixel circuit 114.When TFT 116 is by stress, OLED 120 also by stress.So there are predictable passes between the degeneration of TFT 116 and the whole degeneration of pixel circuit 114 System.TFT to pixel circuit conversion algorithm module 134 or TFT at the conversion algorithm module 134 and numerical data of pixel circuit The combination of reason device 106 is based only on the degeneration of TFT to estimate the degeneration of entire pixel circuit.The embodiment of the present invention can also be by Applied to the system for independently monitoring both TFT and OLED degradation.

Pixel circuit 114 has the component that can be measured.The measured value obtained from pixel circuit 114 in some way with The degeneration of pixel circuit is related.

Fig. 5 shows the example of the pixel circuit 114 of Fig. 4.The pixel circuit 114 of Fig. 5 is 4-T pixel circuits.Pixel electricity Road 114A include the switching circuit with TFT 150 and 152, with reference to TFT 154, driving TFT 156, capacitor 158 and OLED 160。

The grid of switch TFT 150 and the grid of feedback TFT 152 are connected to selection line Vsel.Switch TFT's 154 The first terminal of first terminal and feedback TFT 152 are connected to data line Idata.The Second terminal of switch TFT 150 connects To the grid of grid and driving TFT 156 with reference to TFT 154.The Second terminal of feedback TFT 152 is connected to reference to TFT 154 First terminal.Capacitor 158 is connected between the grid and ground of driving TFT 156.OLED 160 be connected to voltage source Vdd and Between driving TFT 156.In other systems, OLED 160 can also be connected between driving TFT 156 and ground (that is, leakage Pole type of attachment).

When being programmed to pixel circuit 114A, Vsel is height, and voltage or electric current are applied to data line Idata.Data Idata initial flows charge by TFT 150 and to capacitor 158.It is increased with the voltage of capacitor, TFT 154 begin to turn on, and Idata begins through TFT 152 and 154 and flows to ground.When all Idata flow through TFT 152 When with 154, condenser voltage is stablized at certain point.The electric current for flowing through TFT 154 is mirrored in driving TFT 156.

In pixel circuit 114A, by the way that Vsel is set as high and voltage is placed on Idata, inflow can be measured The electric current of Idata node.Alternatively, it by the way that Vsel is set as high and electric current is placed on Idata, can measure in Idata Voltage at node.In TFT degradation, the voltage (or electric current) of measurement will change, and allow to record the measurement to degeneration.In the picture In plain circuit, analog voltage/current 112 shown in Fig. 4 is connected to Idata node.The measurement of voltage or electric current can be sent out It is raw from anywhere in along connection between data driver IC 110 and TFT 116.

In Fig. 4, the transfer algorithm of TFT to pixel circuit is applied to the measured value 132 from TFT 116.But it can To use the current/voltage information read from each position other than TFT 116.For example, OLED voltage 122 can be by It is included in the TFT degradation data 132 of measurement.

Fig. 6 shows another example of the system 100 of Fig. 3.The system 100 of Fig. 6 measures OLED voltage 122.Therefore, it surveys (" the TFT and OLED voltage degraded data of measurement in Fig. 6 related with the degeneration of TFT 116 and OLED 120 of data 132 of amount 132A”).Related signal implements TFT to pixel electricity to 130 pairs of the compensation functions module of Fig. 6 with both TFT degradation and OLED degradation The transfer algorithm 134 on road.TFT to pixel circuit conversion algorithm module 134 or TFT to pixel circuit conversion algorithm module 134 and the combination of digital data processor 106 degeneration of entire pixel circuit is estimated based on TFT degradation and OLED degradation.TFT Degeneration and OLED degradation can be measured separately and independently.

Fig. 7 shows the example of the pixel circuit 114 of Fig. 6.The pixel circuit 114B of Fig. 7 is 4-T pixel circuits.Pixel electricity Road 114B include the switching circuit with TFT 170 and 172, with reference to TFT 174, driving TFT 176, capacitor 178 and OLED 180。

The grid of switch TFT 170 and the grid of switch TFT 172 are connected to selection line Vsel.The of switch TFT 172 One terminal is connected to data line Idata, and the first terminal of switch TFT 170 is connected to the Second terminal of switch TFT 172, should The Second terminal of switch TFT 172 is connected to the grid of the grid and driving TFT 176 with reference to TFT 174.Switch TFT's 170 Second terminal is connected to the first terminal with reference to TFT 174.Capacitor 178 is connected between the grid and ground of driving TFT 176. The first terminal of driving TFT 176 is connected to voltage source Vdd.With reference to the Second terminal and the second of driving TFT 176 of TFT 174 Terminal is connected to OLED 180.

When being programmed to pixel circuit 114B, Vsel is height, and voltage or electric current are applied to data line Idata.Data Idata initial flows charge by TFT 172 and to capacitor 178.It is increased with the voltage of capacitor, TFT 174 begin to turn on, and Idata begins through TFT 170 and 174 and OLED 180 flows to ground.When all Idata flow When by TFT 170 and 174, condenser voltage is stablized at certain point.The electric current of TFT 174 is flowed through in driving TFT 176 In be mirrored.In pixel circuit 114B, by the way that Vsel is set as high and voltage is placed on Idata, inflow can be measured The electric current of Idata node.Alternatively, it by the way that Vsel is set as high and electric current is placed on Idata, can measure in Idata Voltage at node.In TFT degradation, the voltage (or electric current) of measurement will change, and allow to record the measurement to degeneration.Note that Different from the pixel circuit 114A of Fig. 5, electric current flows through OLED 180 now.Therefore the measurement carried out at Idata node Now partly related to OLED voltage, which will degenerate with the time.In pixel circuit 114B, show in Fig. 6 The analog voltage/current 112 gone out is connected to Idata node.Data-driven can be occurred along to the measurement of voltage or electric current From anywhere in connection between device IC 110 and TFT 116.

With reference to figure 3, Fig. 4 and Fig. 6, pixel circuit 114 can allow TFT 116 export electric current be measured, and by with Make the TFT degradation data 132 measured.Pixel circuit 114 can allow certain part of OLED efficiency to be measured, and be used as surveying The TFT degradation data 132 of amount.Pixel circuit 114 may also allow for charging to node, and measured value can be this node discharge The time spent in.Pixel circuit 114 can allow its any part electrically to be measured.In addition, during the given time Charged/discharged level can be used for ageing management.

With reference to figure 8, the example of the module of the compensation scheme for the system applied to Fig. 4 is described.The compensation function of Fig. 8 Module 130 includes analog/digital (A/D) converter 140.The TFT degradation data 132 of measurement is converted to number by A/D converter 140 The measurement of word, TFT voltage/currents 112 shown in Fig. 4 are connected to Idata node.The measurement of voltage or electric current can occur From anywhere in along connection between data driver IC 110 and TFT 116.

When being programmed to pixel circuit 114B, Vsel is height, and voltage or electric current are applied to data line Idata.Data Idata initial flows charge by TFT 172 and to capacitor 178.It is increased with the voltage of capacitor, TFT 174 begin to turn on, and Idata begins through TFT 170 and 174 and OLED 180 flows to ground.When all Idata flow When by TFT 152 and 154, condenser voltage is stablized at certain point.The electric current of TFT 154 is flowed through in driving TFT 156 In be mirrored.In pixel circuit 114A, by the way that Vsel is set as high and voltage is placed on Idata, inflow can be measured The electric current of Idata node.Alternatively, it by the way that Vsel is set as high and electric current is placed on Idata, can measure in Idata Voltage at node.In TFT degradation, the voltage (or electric current) of measurement will change, and allow to record the measurement to degeneration.Note that Different from the pixel circuit 114A of Fig. 5, electric current flows through OLED 180 now.Therefore the measurement carried out at Idata node Now partly related to OLED voltage, which will degenerate with the time.In pixel circuit 114B, show in Fig. 6 The analog voltage/current 112 gone out is connected to Idata node.Data-driven can be occurred along to the measurement of voltage or electric current From anywhere in connection between device IC 110 and TFT 116.

With reference to figure 8, the example of the module of the compensation scheme for the system applied to Fig. 4 is described.The compensation function of Fig. 8 Module 130 includes analog/digital (A/D) converter 140.The TFT degradation data 132 of measurement is converted to number by A/D converter 140 The TFT degradation data 132B of the measurement of word.Conversions of the TFT degradation data 132B of the measurement of the number in TFT to pixel circuit The pixel circuit degradation data 136 being computed is converted at algoritic module 134.The pixel circuit degradation data 136 being computed It is stored in look-up table 142.Longer time may be spent due to measuring TFT degradation data from some pixel circuits, The pixel circuit degradation data 136 being computed is stored in look-up table 142 to use.

In fig. 8, the transfer algorithm 134 of TFT to pixel circuit is the algorithm of number.The TFT of number is to pixel circuit Transfer algorithm 134 can be realized in such as microprocessor, FPGA, DSP or other devices, but be not limited to these examples.It looks into Look for table 142 that can be realized by using memory (such as SRAM or DRAM).The memory can be (such as micro- in other devices Processor or FPGA) in, or can be independent device.

The pixel circuit degradation data 136 being computed being stored in look-up table 142 is total for digital data processor 106 It is available.Therefore, not being just must be to the TFT of each pixel when being needed using data digital data processor 106 Degraded data 132 measures.Infrequently (for example, every 20 hours primary, or less) degraded data 132 can be measured.Separately A kind of situation is distributed using dynamic time for degenerating to measure, and at first than more frequently extracting, is saturated in aging Extraction less frequently later.

Digital data processor 106 may comprise compensating for module 144, and the compensating module 144 from video source 102 for obtaining It must be used for the input brightness data of pixel circuit 114, and repair based on the degraded data of the pixel circuit or other pixel circuits Change it.In fig. 8, module 144 changes brightness data using the information from look-up table 142.

Note that the system that the configuration of Fig. 8 can be applied to Fig. 3 and Fig. 6.Note that look-up table 142 and compensation functions module 130 are provided separately, still, can be in compensation functions module 130.Note that look-up table 142 and digital data processor 106 are provided separately, still, can be in digital data processor 106.

Fig. 9 shows the module 144 of digital data processor 106 and an example of look-up table 142.With reference to figure 9, TFT Output to the conversion algorithm module 134 of pixel circuit is integer value.This integer is stored in look-up table 142A and (corresponds to figure The 142 of 8) in.Its position in look-up table 142A is related to position of the pixel in displayer.Its value is one Number, and be added to the brightness data 104 of number and degenerated with compensating.

For example, the brightness data of number can be represented as 8 bits (256 values) being used for the brightness of pixel.Value 246 can Indicate the maximum brightness of pixel.Value 128 can indicate about 50% brightness.Value in look-up table 142A can be added to bright The number degenerated with compensation in degrees of data 104.Therefore, the compensating module in digital data processor 106 (the 144 of Fig. 7) can lead to Digital adder 144A is crossed to realize.Note that the brightness data of number can pass through appointing depending on used driver IC Quantity of anticipating bit (for example, 6 bits, 8 bits, 10 bits, 14 bits, etc.) indicate.

In Fig. 3, Fig. 4, Fig. 6, Fig. 8 and Fig. 9, the conversion algorithm module 134 of TFT to pixel circuit has the TFT measured Degraded data 132 or 132A are as input, and the pixel circuit degradation data 136 calculated is as output.But it is also possible to deposit In other inputs of the system for calculating offset data, as shown in Figure 10.The conversion that Figure 10 shows TFT to pixel circuit is calculated The example of the input of method module 134.In Fig. 10, TFT to the conversion algorithm module 134 of pixel circuit based on additional input 190 (for example, temperature, other voltages etc.), empirical 192 or combinations thereof come handle measurement data (Fig. 3, Fig. 4, Fig. 8 and The 132 of Fig. 9；The 132A of Fig. 5；The 132B of Fig. 8 and Fig. 9).

Additional input 190 may include the parameter measured, such as the voltage that is read from current-programmed pixel and from voltage The electric current that programmed pixels are read.These pixels can be different from the pixel circuit of the signal of measurement is obtained from it.For example, can be from " pixel under test " obtains measured value, and the measured value and another measured value from " reference pixel " are made in combination With.As described below, in order to determine how the brightness data of modification pixel, the number of other pixels in display can be used According to.Additional input 190 may include the measured value of the ambient light in light measurement value, such as room.Around certain of panel periphery Kind test structure or discrete device can be used to measuring environment light.Additional input may include humidity measurements, temperature reading The feedback of number, mechanical stress reading, other environmental stress reading and the test structure on panel.

It can also include empirical parameter 192, such as the OLED caused by reduction efficiency in luminance loss (Δ L), The drift (Δ Voled) at any time of OLED voltage, Vt drifts dynamic effect, with the performance-relevant parameters of TFT (such as Vt, Δ Vt, mobility (μ)), the inhomogeneities between pixel, the DC bias voltages in pixel circuit, the pixel circuit based on current mirror Gain change, pixel circuit performance based on short-term and long-term drift, dropped by IR caused by pixel circuit operate voltage change Change and ground bounce (ground bounce).

With reference to figure 8 and Fig. 9, the TFT in module 134 is to the transfer algorithm of pixel circuit and in digital data processor Backoff algorithm 144 in 106 works together, so that the TFT degradation data 132 of measurement is converted to luminance correction factor.Brightness Correction factor has about the brightness data that how change for given pixel to compensate the information of degeneration within the pixel.

In fig.9, the major part of this conversion is carried out by the conversion algorithm module 134 of TFT to pixel circuit.Its Intensity correction values are fully calculated, and the digital adder 144A in digital data processor 106 is simply by gamma correction Value is added on digital brightness data 104.But system 100 may be implemented so that TFT to pixel circuit transfer algorithm mould Block 134 only calculates degradation values, and digital data processor 106 calculates luminance correction factor according to the data.TFT is to pixel The transfer algorithm 134 of circuit may be used fuzzy logic, neural network or other algorithm structures degraded data is converted to it is bright Spend correction factor.

The value of luminance correction factor can allow all to keep constant regardless of the degeneration visible light in pixel circuit.It is bright The value of degree correction factor can allow the brightness for the pixel degenerated to be changed not at all；On the contrary, the brightness of non-degraded pixels It reduces.In this case, whole display gradually loses brightness such as the passage of time, but uniformity can be compared with It is high.

Luminance correction factor calculate can according to inhomogeneities compensate algorithm (such as constant luminance algorithm, reduce it is bright Degree algorithm or combinations thereof) it realizes.Constant luminance algorithm and reduction brightness algorithm can be in the transfer algorithms of TFT to pixel circuit It is realized on module (for example, 134 of Fig. 3) or digital data processor (for example, 106 of Fig. 3).There is provided constant luminance algorithm with Come increase degeneration pixel brightness to match non-degraded pixels.It provides and reduces brightness algorithm not degenerate for reducing The brightness of pixel 244 is to match the pixel of degeneration.These algorithms can be by TFT to pixel circuit conversion algorithm module, number Digital data processor (for example, 144 of Fig. 8) or combinations thereof is realized.Note that these algorithms are only example, and it is uneven Property compensation algorithm be not limited to these algorithms.

With reference to figure 11A-11E, the experimental result of the algorithm of inhomogeneities compensation is described in detail.In test, AMOLED Display includes multiple pixel circuits, and is driven by such as Fig. 3, Fig. 4, Fig. 6, Fig. 8 and system shown in Fig. 9.Note that driving The circuit of displayer is not shown in Figure 11 A-11E.

Figure 11 A schematically show the displayer 240 (operation period t=0 hour) for starting operation.Video source Maximum luminance data is initially output to each pixel by (the 102 of Fig. 3, Fig. 4, Fig. 7, Fig. 8 and Fig. 9).Since display 240 is new , therefore no pixel is to degenerate.As a result, the brightness of all pixels the output phase etc., and therefore all pixels are shown Uniform brightness.

Next, video source by maximum luminance data be output in the display between some pixels, as shown in Figure 11 B. Figure 11 B schematically show displayer 240, which has operated for the regular period, wherein maximum Brightness data is applied to the pixel among display.Maximum luminance data is output to pixel 242 by video source, while it will most Small brightness data (for example, zero luminance data) is output to the pixel 244 of 242 periphery of pixel.When it is longer by this section of maintenance Between, such as 1000 hours.As a result, the pixel 242 in maximum brightness will degenerate, and the pixel 244 in 0 brightness will not have It degenerates.

At 1000 hours, maximum luminance data was output to all pixels by video source.According to the backoff algorithm used, knot Fruit is different, as shown in Figure 11 C-11E.

Figure 11 C schematically show displayer 240, and the displayer 240 is without applying backoff algorithm. As shown in Figure 11 C, if without backoff algorithm, the pixel 242 degenerated will be with the brightness lower than non-degraded pixels 244.

Figure 11 D schematically show displayer 240, which applies constant luminance algorithm. Constant luminance algorithm is implemented for increasing the brightness data for the pixel degenerated, so that the brightness number for the pixel 242 degenerated According to the brightness data of matching non-degraded pixels 244.For example, it is increased to be provided by the pixel 242 of stress to increase brightness algorithm Electric current, and not provided constant electric current by the pixel of stress 244.Both pixel and non-degraded pixels of degeneration have phase Same brightness.Therefore, display 240 is uniform.Differentiated aging is compensated for, and maintains brightness, but is needed more More electric currents.Since the electric current of some pixels constantly increases, this will cause display to consume more electric currents at any time, And more power are therefore consumed at any time, because power consumption is related to current drain.

Figure 11 E schematically show displayer 240, which applies reduction brightness algorithm. Reduce the brightness data that brightness algorithm reduces non-degraded pixels, so that the brightness data matching of non-degraded pixels 244 is moved back The brightness data of the pixel 242 of change.For example, it is to be provided constant OLED current by the pixel 242 of stress, and be to reduce brightness algorithm Unstressed pixel 244 provides the electric current reduced.The brightness having the same of both the pixel and non-degraded pixels of degeneration.Cause This, display 240 is uniform.Differentiated aging is compensated for, and it requires lower Vsupply, but it is bright at any time Degree reduces.Since the algorithm does not increase the electric current of any pixel, will not cause to increase power consumption.

With reference to figure 3,8 bits or 256 can be only used only in component (such as video source 102 and data driver IC 110) Discrete brightness value.So if video source 102 exports maximum brightness (255 brightness values), have no idea to increase any volume Outer brightness, because of the maximum brightness that the component that pixel has been in system is supported.Similarly, if video source 102 is defeated Go out minimum brightness (0 brightness value), then has no idea to subtract any brightness.Digital data processor 106 can implement gray level Compression algorithm retains some gray levels.Figure 12 shows the digital data processor for including grayscale compression algorithm module 250 106 implementation.Grayscale compression algorithm 250 obtains the vision signal 104 (251) indicated by 256 brightness values, and is carried out to it Transformation is to use less brightness value (252).For example, minimum brightness can be indicated with gray level 50, rather than with gray level 0 To indicate minimum brightness.Similarly, maximum brightness can be indicated with gray level 200.In this way, there are some gray levels It is retained for the increase (254) in future and reduces (253).Note that the variation of gray level does not reflect actual expected ash Spend the variation of grade.

According to an embodiment of the invention, estimate the degeneration of (prediction) entire pixel circuit and generate the side of luminance correction factor Case ensures the uniformity in display.According to an embodiment of the invention, the aging of some components or entire circuit can be mended It repays, thus ensures the uniformity of display.

According to an embodiment of the invention, the transfer algorithm of TFT to pixel circuit allows to improve display parameters, it may for example comprise The constant brightness uniformity and color homogeneity on entire panel over time.Due to turning for TFT to pixel circuit Scaling method receives additional parameter, for example, temperature and ambient light, therefore can compensate due to being shown caused by these additional parameters Show any change in device.

TFT to the conversion algorithm module (the 134 of Fig. 3, Fig. 4, Fig. 6, Fig. 8 and Fig. 9) of pixel circuit, compensating module (Fig. 8's 144, Fig. 9 144A), inhomogeneities backoff algorithm, constant luminance algorithm, reduce brightness algorithm and grayscale compression algorithm can be with It is realized by the combination of any hardware, software or hardware and software with function described above.Software code, instruction And/or all or part of sentence can be stored in computer-readable memory.Furthermore it is possible to be embedded in the table in carrier wave Show that the computer data signal of software code, instruction and/or sentence can be via communication network transmission.It is such computer-readable Memory and computer data signal and/or its carrier and hardware, software and combinations thereof are also within the scope of the invention.

Referring again to FIGS. 3, Fig. 3 shows the dispalying systems 100 by the way that backoff algorithm to be applied to numerical data 104 Operation.Particularly, Fig. 3 shows the operation of the pixel in active matrix organic light-emitting diode (AMOLED) display. Display system 100 includes pel array.Video source 102 includes the brightness input data for pixel.Brightness data is by with number The form of input data 104 is sent to digital data processor 106.Digital input data 104, which can be expressed as being present in 0, to be arrived The data of 8 bits of the integer value between 255, wherein larger integer value corresponds to higher brightness degree.At numerical data Reason device 106 can be put down alternately through the resolution ratio of video source 102 is for example zoomed to intrinsic screen resolution, adjusts color Weighing apparatus handles digital input data 104 to video source 102 using Gamma correction.Digital data processor 106 can also be based on Degraded data 136, which degenerates to the application of digital input data 104, to be corrected.After the treatment, digital data processor 106 is by result Numerical data 108 is sent to data driver integrated circuit (IC) 110.Data driver IC 110 converts numerical data 108 For analog voltage or electric current output 112.Data driver IC 110 may be implemented as such as module including digital analog converter. Analog voltage or electric current 112 are provided to pixel circuit 114.Pixel circuit 114 may include Organic Light Emitting Diode (OLED) With thin film transistor (TFT) (TFT).A TFT in TFT in pixel circuit 114 can be the driving that driving current is supplied to OLED TFT.In response to flowing to the driving current of OLED, OLED emits visible light 126.With with by driving TFT to flow to the electric current of OLED The relevant brightness emission visible light of amount 126.

In the configuration that analog voltage or electric current 112 are program voltage, the driving TFT in pixel circuit 114 can pass through Such as the grid of driving TFT is biased to supply OLED according to analog voltage or electric current 112 with program voltage.Pixel circuit 114 Can be program current applied to each pixel in analog voltage or electric current 112 rather than program voltage in the case of operates. The current mirror in each pixel circuit 114 can be used come each according to being applied to using the display system 100 of program current The program current of pixel is by driving TFT that driving current is applied to OLED.

Aspect (including the hardware in pixel circuit 114 of the brightness of the visible light 126 of transmitting in by pixel circuit 114 Gradually degenerate) influence.Drive TFT that there is threshold voltage, and since driving TFT is by stress and aging, threshold voltage meeting Change with the time.The brightness of the visible light 126 of transmitting can be driven the threshold voltage of TFT, the both ends OLED voltage The influence of drop and the efficiency of OLED.The efficiency of OLED is the brightness of the visible light 126 of transmitting and flows through the driving electricity of OLED The ratio of stream.In addition, it generally can be in fabrication tolerance and display system 100 due to for example driving TFT and OLED to degenerate Pixel differentiated aging caused by it is uneven in entire display system 100.Inhomogeneities in display 100 is logical It is commonly referred to as display moire (mura) or defect.In the display 100 with OLED arrays, wherein OLED arrays have uniform Luminous efficiency and by with uniform threshold voltage of the grid TFT driving threshold voltage, when all pixels in display All with identical analog voltage or electric current 112 come when programming, the brightness of display will be uniform.But when programming in the same manner When, as OLED the and TFT agings in each pixel and degradation characteristics change, the brightness of display is no longer uniform.

It can be degenerated by the amount of drive current of the OLED in pixel circuit 114 to compensate by increasing to send.According to this A disclosed embodiment can be realized by adjusting the numerical data 108 exported from digital data processor 106 to aobvious Show the compensation of the degeneration of device 100.Digital data processor 106 receives degraded data 136 from compensating module 130.Compensating module 130 Receive the degraded data 132 of the measured value based on the parameter in pixel circuit 114.Alternatively, it is sent to compensating module 130 Degraded data 132 can be based on the estimation of the estimated performance of the hardware aspect in pixel circuit 114.Compensating module 130 includes using In the module 134 for implementing algorithm 134 (such as TFT to the transfer algorithm of pixel circuit).Degraded data 132 can indicate pixel The hardware aspect of circuit 114 has been degenerated how many electric data.The degraded data 132 measured or estimated from pixel circuit 114 can To indicate one or more features of pixel circuit 114.

In the configuration that analog voltage or electric current 112 are program voltage, program voltage usually by digital input data 104 It determines, digital input data 104 is converted into voltage in data driver IC 110.Present disclose provides compensation to influence from every The method of uneven feature in each pixel circuit 114 of the brightness of the visible light 126 of a pixel emission.In numerical data 108 are transferred to before data driver IC 110, by digital data processor 106 adjust digital input data 104 come Execute compensation.

Figure 13 is the data flow of the compression and the compensation that show the luminosity input data 304 for driving displayer Cheng Tu.Data flowchart shown in Figure 13 includes digital data processor block 306, can regard number shown in Fig. 3 as A kind of embodiment of digital data processor 106.Referring again to Figure 13, video source provides luminosity input data 304.Input data 304 be the integer value of one group of 8 bit.Input data 304 includes the integer value being present between 0 to 255, and wherein these values indicate 256 possible programmable shading values of the pixel in displayer.For example, 255 can correspond to use maximum brightness The pixel of programming and 127 it can correspond to the pixel programmed with the general half of maximum brightness.In input data 304 and Fig. 3 The digital input data 104 shown is similar.Referring again to Figure 13, input data 304 is sent to digital data processor block 304.In digital data processor block 304, input data 304 is multiplied by 4 (310), so as to by the input data 304 of 8 bits It is converted into the result data 312 of 10 bits.After being multiplied by 4 (310), result data 312 is one group and is present between 0 to 1020 10 bits integer.

By converting the input data 304 of 8 bits to the result data 312 of 10 bits, result data 312 can be located Reason is degenerated for carrying out compensation brightness with finer step compared with the input data 304 that can be applied to 8 bits.10 bits Result data 312 can also be more accurately translated to the program voltage according to gamma correction.Gamma correction is display technology Known a kind of nonlinear power law (power law) correction in field.To input data application gamma correction for example for negative It can be advantageous for the log characteristic of perception luminosity in load human eye.According to the one side of the disclosure, number will be inputted Input data 304 is transformed into higher quantized field by the operation that 4 (310) are multiplied by according to 304.Although the disclosure includes being multiplied by 4 (310), but in one embodiment, input data 304 can be multiplied by arbitrary number, to convert input data 310 Into higher quantized field.Conversion can advantageously be utilized to be multiplied with 2 exponential (such as 4), and but the present disclosure is not limited thereto. In addition, the disclosure can be carried out in the case where input data 304 not being transformed into higher quantized field.

Result data 312 is multiplied by compressibility factor K (314).Compressibility factor K is the number with the value less than 1.By number of results Being multiplied by K (314) according to 312 allows the result data 312 of 10 bits being scaled compressed data 316.Compressed data 316 Being one group has range from 0 to K and the integer of 10 bits of the value of 1020 product.Next, compressed data 316 are mended Repay the degeneration (318) of display hardware.By by additional data increment be added on integer corresponding with each pixel intensity come Compensate compressed data 316 (318).It is executed pair according to the degraded data 336 for being sent to digital data processor block 306 The compensation of degeneration.Degraded data 336 is that indicate will be in digital number according to the degeneration corresponding to each pixel in display hardware According to the numerical data applied to the compensation rate of compressed data 316 in processor module 306.After degradation compensation (318), Export compensated data 308.Compensated data 208 are the integers of one group of 10 bit with the probable value between 0-1023 Value.The numerical data 108 that compensated data 308 are exported with the slave digital data processor 106 in Fig. 3 is class in some aspects As.Referring again to attached drawing 13, compensated data 308 are supplied to display driver, such as including digital analog converter Display driver, to create program voltage for the pixel in displayer.

The degeneration of display hardware can come from cloud pattern defects (inhomogeneities), OLED voltage drop, the voltage threshold for driving TFT The variation of value and OLED luminous efficiencies.The degeneration of display hardware each generally corresponds in order to compensate for degeneration and applied to pixel electricity The additional voltage increment on road.For specific pixel, for compensation hardware degenerate needed for the increment of additional voltage can be by Referred to as：V_mura、V_Th、V_OLEDAnd V_efficiency.According to V_mura、V_Th、V_OLEDAnd V_efficiencyFunction D (V_mura,V_Th,V_OLED, V_efficiency), each hardware degeneration can be mapped in the corresponding increment in data step.For example, relationship can be by expression formula 1：D(V_mura,V_Th,V_OLED,V_efficiency)=int [(2^nBits-1)(V_mura+V_Th+V_OLED+V_efficiency)/V_Max] provide, wherein NBits is the quantity and V of the bit in the data group compensated_MaxIt is the largest program voltage.In expression formula 1, int [] is function, assesses the content of bracket and returns to immediate integer.It is sent to moving back for digital data processor block 306 It can be according to the relationship D (V provided in expression formula 1 to change data 336_mura,V_Th,V_OLED,V_efficiency) come the digital number that creates According to.In an embodiment of the disclosure, degraded data 336 can be the array of numerical data, which, which corresponds to, wants The compensation rate of compressed data applied to each pixel in displayer.The array of digital data be one group can be with By the way that offset increment to be added to the compressed data of each pixel or is subtracted from the compressed data of each pixel partially Move increment and applied to compressed data offset increment.This group of offset increment usually can be set of number data, the group Numerical data have with applied to the corresponding entry of compensation rate needed for each pixel in displayer.Compensation rate can be with It is the increment in data step required in order to compensate for degeneration according to expression formula 1.In configuration, in degraded data array Position in 336 can correspond to position of the pixel in displayer.

For example, table 1 below provides the numerical examples according to the compression of the input data of Figure 13.Table 1, which provides, to be multiplied With the example value of 4 (310) and one group of input data 304 being multiplied by after K (314).In the example that table 1 provides, the value of K is 0.75.In table 1, first row provides the example value of the integer in this group of input data 304.Secondary series is provided by will be right The input data values answered be multiplied by 4 (310) and this group of result data 312 that creates in integer example value.Third row provide The example value of number in the compressed data of the group that is created by the value of corresponding result data 312 is multiplied by K 316, In K example value be 0.75.Last row is to correspond to illustratively to pass through shown in third row when no application compensates The output voltage of the data 316 of compression.Last, which is classified as, creates with maximum program voltage for the example display system of 18V. In the numerical example being shown in Table 1, programming output voltage corresponding with the input data with maximum input 255 compares maximum voltage Low 4.5V or more.4.5V can regard the compensation budget of display system as, and be properly termed as voltage headroom V_headroom.According to this Disclosed one side, 4.5V are used for compensating the degeneration of the pixel in displayer.

Table 1：The numerical example of input data compression

According to an embodiment of the disclosure, the amount for providing the voltage available that compensation is degenerated is V_headroom。V_headroom Amount can advantageously be preserved for compensate displayer in most serious luminance degradation pixel degeneration.Pass through It is preserved for compensating the V for the pixel that most serious is degenerated_headroomAmount, it can be advantageous to maintain the relative brightness of display.For Compensate the V needed for the pixel with maximum amount of degradation in displayer_headroomAmount provided by following expression formula 2： V_headroom=max [V_mura+V_Th+V_OLED+V_efficiency].In expression formula 2, V_mura、V_Th、V_OLEDAnd V_efficiencyIn it is each A can be the array of value corresponding with the amount of the extra voltage needed for the pixel compensated in display, and in the array of the value In entry can correspond to each pixel in display.That is, V_muraCan be for compensation display moire or not The array of voltage needed for uniform defect；V_ThIt can be the array of the voltage threshold of the driving TFT of the pixel in display； V_OLEDIt can be the array of the OLED voltage of the pixel in display；And V_efficiencyCan be for the picture in compensation display The array of voltage needed for the OLED efficiency degeneration of element.In expression formula 2, max [] is function, assesses the value in bracket Array simultaneously returns to the maximum value in array.

As referring to Fig.1 3 and table 1 it is apparent that, K selection influence can be used for compensate display in degeneration V_headroom Amount.Smaller K values are selected to lead to bigger V_headroomAmount.Make the need for compensation due to the aging of display wherein It asks over time and in the configuration of the increased disclosure, according to the degeneration over time of display, the value of K Can advantageously it reduce over time.Reduce K and allow for the uniformity compensation on whole display, So that the pixel for receiving identical digital input data actually emits the light of same brightness, but uniformity compensation is to drop The overall brightness of low whole display is cost.Figure 14-17 provides the method for selecting and adjusting K.

Figure 14 is the method shown for selecting compressibility factor according to the design of display requirement and pixel circuit Flow chart.When the operation of the method shown by the flow chart of Figure 14, display requires and the pixel circuit design quilt of display Analysis, to estimate the V for the pixel in display_mura、V_Th、V_OLEDAnd V_efficiencyMaximum value (405).Estimate (405) Can based on for example to include that similar with the pixel circuit in display 100 aging of display of pixel circuit is related The empirical data of experimental result realize.Alternatively, estimation (405) can be based on the pixel circuit in display 100 The numerical model of estimated performance is realized based on the simulation model of software.Estimate that (405) are also conceivable to the volume of headroom voltage Outer safety margin, to consider the statistically predictable variation between the pixel circuit in display 100.In response to estimation (405), required voltage headroom (410) is calculated.Required voltage headroom V is calculated according to expression formula 2_headroom.Once calculating V_headroom, just according to expression formula 3：K=1-V_headroom/V_MaxTo calculate (415) compressibility factor K, wherein V_MaxIt is display 100 maximum program voltage.Then (420) compressibility factor K is set, compressibility factor K is for compression and backoff algorithm, such as Figure 13 Data flowchart shown by compression algorithm.

Figure 15 is to show to adjust distribution map according to predetermined headroom to select the flow chart of the method for compressibility factor.Selection is net Air-conditioning section distribution map (505).The first module 505 in the flow chart of Figure 15, which has graphically illustrated three possible headroom and adjusted, divides Butut, as distribution map 1, distribution map 2, distribution map 3.The distribution map shown is K time history plots.Time shaft can be with It is, for example, the hourage of display 100 used.In all 3 distribution maps, K reduces over time.Pass through Reduce K, voltage (V over time_headroom) additional quantity can be used for compensating.Example point in the first module 505 Butut includes distribution map 1, and K is maintained constant level until arrival time threshold value, and hereafter K with usage time it is linear Ground reduces.Distribution map 2 is staged distribution map, and K is maintained constant level for a period of time, is then reduced to K smaller Value, and the time point for maintaining it to reduce again until another its.Distribution map 3 be it is linear reduce distribution map, by K be set as with Usage time gradually linearly to reduce.The compensation technique that distribution map can use during the service life for display according to user Preference selected by user profile setting.For example, user may want to before reduce brightness, the total of display is maintained Body maximum brightness, which reaches, specifically uses hourage.Brightness is gradually lowered for others since the validity period of display May be suitable for user.

Once headroom has been selected to adjust distribution map (505), (510) display usage time is just monitored.In given use At time, the value (515) of compressibility factor K is determined according to usage time and the distribution map of selection.Then compressibility factor K is set (520), and continue monitor scope usage time (510).After setting K (520), K can be used for compressing and compensate Algorithm, for example, Figure 13 the compression algorithm that illustrates of data flow.According to the one side of the disclosure, shown in Figure 15 setting and The method for adjusting K is setting and adjusts the dynamic approach of K, because the value of K is according to the usage time of display 100, with the time Passage and update.

Figure 16 is to show the dynamic measurement according to the degraded data more than the threshold value on first precompensation to select The flow chart of the method for compressibility factor.It is measured from the part of the pixel circuit of the pixel in display 100, to measure V_mura、V_Th、V_OLEDAnd V_efficiency(605) and according to expression formula 2 V is calculated_headroom.Then, compared by calculating difference The V currently calculated in time t2_headroomValue and the V that is calculated in earlier time t1_headroomValue between difference (610).Difference Value is Δ V_headroom, and according to expression formula 5：ΔV_headroom=(V_headroom)_t2-(V_headroom)_t1To calculate.In expression formula 5 In, t1 is time last time for adjusting compensation factor K, and t2 is the current time.Subscript in the right-hand side of expression formula 5 Indicate the time of the assessment of the amount in bracket.

Then compare the Δ V being calculated_headroomValue and compensation threshold value V_thresh(615).If Δ V_headroomIt is more than V_thresh, then K (620) is changed.If Δ V_headroomLess than or equal to V_thresh, then K is not changed.It can be according to expression formula 6：K_new =K_old/ A-B changes the value of K, wherein K_newIt is the new value of K, K_oldIt is the old value of K, and A and B is for application and different Technology and the value set.For example, A and B can be set based on empirical results, the empirical results come self-check due to display Characteristic caused by the aging of the similar pixel circuit of pixel circuit for being used for driving the OLED in each pixel in device 100 is moved back The experiment of change.Similar measurement or user's input can also be used to setting V_thresh.Then, setting (625) compressibility factor K with The compression algorithm that data flow in compression and backoff algorithm, such as Figure 13 illustrates.Continue to measure to degenerate and measure (605), Continue to calculate Δ V_headroom(610), and whenever Δ V_headroomMore than V_threshWhen K (620) updated according to expression formula 6.Root According to the one side of the disclosure, the method that K is adjusted shown in Figure 16 is to adjust the dynamic approach of K, from display 100 because according to Degeneration measured value that interior pixel circuit is collected updates the value of K over time.

It alternatively, can be based on the V of measurement_headroom(620) compressibility factor is changed according to expression formula 3.According to Figure 16 Shown in the one side of method that provides in flow chart, maintain the value of K to change K at this time until (615) occur for threshold event (620).The method for adjusting compressibility factor K for implementing to provide in Figure 16 can make according to staged distribution map with the time Passage reduce K.

Figure 17 is to show the dynamic measurement according to the degraded data more than the maximum value previously measured to select to compress The flow chart of the method for the factor.It is measured from the part of the pixel circuit of the pixel in display 100, to measure V_mura、V_Th、V_OLEDAnd V_efficiency(605)。V_mura、V_Th、V_OLEDAnd V_efficiencyMeasured value be referred to as degeneration measured value.Choosing Select the maximum value (710) of degeneration measured value.The maximum value of degeneration can be selected according to expression formula 2.Measure degeneration measured value (605) and the combination of selection maximum value (710) is used for determining the maximum compensation applied to the pixel in display.Compare maximum value With the maximum value (715) of the degeneration measured value previously measured previously measured.If the maximum value currently measured is more than previously to have surveyed The maximum value of amount then calculates (410) V based on current degeneration measured value according to expression formula 2_headroom.Next, according to expression Formula 3 determines (720) compressibility factor K.Compressibility factor (725) is set, and updates maximum value for being carried out with new maximum value Compare (715).Setting compressibility factor (725) illustrates for the data flow in compression and backoff algorithm, such as Figure 13 Compression algorithm.Similar to the method provided in Figure 16, the method that the flow in Figure 17 illustrates is based on from display 100 Degeneration measured value that pixel circuit is constantly collected adjusts the dynamic approach of K.

The disclosure disclosed above can be transmitted to data driver by combining in order to create the permission of appropriate amount at it Before IC the method for compressibility factor K is set and adjusted applied to the voltage headroom amount of the compensation of numerical data to implement.Example Such as, the distribution map selected such as the user in Figure 15 can also be incorporated to according to the setting of Figure 16 or Figure 17 and the method for adjusting K.

In an embodiment of the disclosure, the selection that is provided in Figure 14-17 and the method for adjusting compressibility factor K can be with Digital data processing shown in Figure 13 is used in combination with, and to operate display, while maintaining the uniform luminosity of display.With In setting, method described above allows the relative brightness for maintaining display by compensating the degeneration of the pixel in display. In configuration, method described above allows to tie up given numeral input by the degeneration in the pixel circuit of compensation pixel Hold the luminosity of the pixel in display array.

The present disclosure describes the uniform luminosity for maintaining displayer, but disclosed technology is not limited to this. The disclosure be suitable for include have in response to data input and the range of the system of the array of the device of stimulated characteristic, and Wherein seek equably to maintain the characteristic.For example, the disclosure is suitable for two pole of sensor array, storage unit and solid luminescent Tube display.The disclosure stimulates the data of interested characteristic to input for changing, to maintain uniformity.Although for compressing With the digital luminosity data of compensation to maintain the disclosure of the luminosity of displayer to be described as utilizing TFT and OLED, still The disclosure is suitable for the similar equipment with the display for including light-emitting element array.

Although the particular embodiment of the present invention and application has been shown and described, but it is to be understood that the present invention is unlimited In accurate construction disclosed in this application and layout, and do not departing from the present invention's as defined by the appended claims Various modifications, change and variation can be understood according to foregoing description in the case of spirit and scope.

Claims

1. the method that a kind of degeneration of multiple pixels in display compensates, the multiple pixel has for based on defeated The driving circuit for entering the electric current to be driven through luminescent device, the method includes：

Receive the first luminosity data of the multiple pixel；

First to degenerate according to first measures or estimates to calculate the first voltage headroom compensated needed for the multiple pixel；

Compressibility factor is determined based on the first voltage headroom；

First luminosity data is scaled by the compressibility factor, to create the first compressed data；

It is degenerated by adjusting the first compressed data to compensate the first of the multiple pixel, it is compensated to create first Data；And

The driving circuit is supplied based on the described first compensated data；

Second to degenerate according to second measures or estimates to calculate the second voltage headroom compensated needed for the multiple pixel；

The first voltage headroom is compared with the second voltage headroom to generate voltage headroom fiducial value, and

The compressibility factor is updated using voltage headroom fiducial value.

2. the method as described in claim 1, wherein the voltage headroom fiducial value includes that voltage headroom is poor, and wherein updates The compressibility factor includes that the voltage headroom difference compares with compensation threshold value.

3. method as claimed in claim 2, wherein updating the compressibility factor and including：It is mended if the voltage headroom difference is more than Threshold value is repaid, the value of the compressibility factor is changed into newer compressibility factor.

4. method as claimed in claim 3, wherein updating the compressibility factor and including：If the voltage headroom difference be equal to or Less than compensation threshold value, then the value of the compressibility factor is maintained.

5. the method as described in claim 1, wherein updating the compressibility factor and including：With the function of the compressibility factor by institute The value for stating compressibility factor changes into newer compressibility factor.

6. method as claimed in claim 5, wherein the function of the compressibility factor is linear function.

7. method as claimed in claim 5, wherein the function of the compressibility factor is based on being attributed to and the multiple pixel The feature of the aging of the similar pixel circuit of pixel circuit is degenerated.

8. the method as described in claim 1, wherein creating tool by the way that first luminosity data is multiplied with constant integer There is the result data of bigger bit number and result data is multiplied with the compressibility factor, to realize the scaling.

9. method as claimed in claim 8, wherein first luminosity data includes the integer of 8 bits and first warp The data of compression include the integer of 10 bits.

10. the method as described in claim 1, wherein each of described driving circuit includes at least one thin film transistor (TFT) TFT。

11. method as claimed in claim 10, wherein at least one TFT is N-shaped TFT.

12. method as claimed in claim 10, wherein at least one TFT be used to be driven through the corresponding hair of pixel The electric current of optical device, and the degeneration of wherein the multiple pixel is attributed to the voltage threshold of at least one TFT or returns Because of the drift of the voltage threshold at least one TFT.

13. the method as described in claim 1, wherein including each Organic Light Emitting Diode OLED in the luminescent device.

14. method as claimed in claim 13, wherein the degeneration of the multiple pixel is attributed to the bias voltage of the OLED Or it is attributed to the drift of the bias voltage of the OLED.

15. method as claimed in claim 13, wherein the degeneration of the multiple pixel is attributed to the inefficient of the compensation OLED Voltage needed for rate or be attributed to the compensation OLED inefficient required voltage drift.

16. the method as described in claim 1, wherein the compressibility factor is the distribution map selected based on user and the multiple The usage time of pixel determines.

17. the method as described in claim 1, wherein the compressibility factor be the estimation of the degeneration based on the multiple pixel with And it is determined based on the requirement of display, and wherein described hardware of the estimation based on the multiple pixel and the driving circuit The design of aspect.

18. method as claimed in claim 3, further includes：

Receive the second luminosity data of the multiple pixel；

Second luminosity data is scaled by the newer compressibility factor, to create the second compressed data；

The degeneration of the multiple pixel is compensated by adjusting the second compressed data, to create the second compensated number According to；And

The driving circuit is supplied based on the described second compensated data.

19. the method as described in claim 1, wherein the first of the first degeneration measures or estimates moving back including the multiple pixel The first maximum value changed, and wherein second degenerate second measure or estimate second of the degeneration including the multiple pixel most Big value.

20. the method that a kind of degeneration of multiple pixels in display compensates, the multiple pixel has for being based on The driving circuit for inputting the electric current to be driven through luminescent device, the method includes：

Receive the first luminosity data of the multiple pixel；

Compressibility factor is determined based on the first voltage headroom；

The degeneration of the multiple pixel is compensated by adjusting the first compressed data, to create the first compensated number According to；

Execute the second degeneration second measures or estimates；

The second of second degeneration is measured or estimated to measure or estimate with the first of the first degeneration and is compared to generate degeneration ratio Compared with value, and

The compressibility factor is updated using degeneration fiducial value.

21. method as claimed in claim 20, wherein updating the compressibility factor and including：If the second the second measurement degenerated Or estimation is more than the first of the first degeneration and measures or estimates, and the value of the compressibility factor is changed into newer compressibility factor.

22. method as claimed in claim 21, wherein the value for changing the compressibility factor includes：

Second to degenerate according to second measures or estimates the second voltage headroom for calculating and compensating needed for the multiple pixel；And

Newer compressibility factor is determined based on second voltage headroom.

23. method as claimed in claim 22, wherein the first of the first degeneration measures or estimates including the multiple pixel The first maximum value degenerated, and wherein second degenerate second measure or estimate second of the degeneration including the multiple pixel Maximum value.

24. method as claimed in claim 20, wherein being created by the way that first luminosity data is multiplied with constant integer Result data with bigger bit number and result data is multiplied with the compressibility factor, to realize the scaling.

25. method as claimed in claim 24, wherein first luminosity data includes the integer and described first of 8 bits Compressed data include the integer of 10 bits.

26. method as claimed in claim 20, wherein each of described driving circuit includes at least one thin film transistor (TFT) TFT。

27. method as claimed in claim 26, wherein at least one TFT is N-shaped TFT.

28. method as claimed in claim 26, wherein at least one TFT be used to be driven through the corresponding hair of pixel The electric current of optical device, and the degeneration of wherein the multiple pixel is attributed to the voltage threshold of at least one TFT or returns Because of the drift of the voltage threshold at least one TFT.

29. method as claimed in claim 20, wherein including each Organic Light Emitting Diode OLED in the luminescent device.

30. method as claimed in claim 29, wherein the degeneration of the multiple pixel is attributed to the bias voltage of the OLED Or it is attributed to the drift of the bias voltage of the OLED.

31. method as claimed in claim 29, wherein the degeneration of the multiple pixel is attributed to the inefficient of the compensation OLED Voltage needed for rate or be attributed to the compensation OLED inefficient required voltage drift.

32. method as claimed in claim 20, wherein the compressibility factor is the distribution map selected based on user and described more The usage time of a pixel determines.

33. method as claimed in claim 20, wherein the compressibility factor is the estimation of the degeneration based on the multiple pixel And determined based on the requirement of display, and wherein described estimation is hard based on the multiple pixel and the driving circuit Design in terms of part.

34. method as claimed in claim 22, further includes：

Receive the second luminosity data of the multiple pixel；

The driving circuit is supplied based on the described second compensated data.