This application claims the priority benefit of China application serial no. 202311656450.1, filed on Dec. 5, 2023. The entirety of the above-mentioned patent application is hereby incorporated by reference herein and made a part of this specification.
This disclosure relates to an electronic device with a compensation function.
Light Emitting Diode (LED) can be used for backlighting or directly as displays, but the entire LED array is susceptible to a variety of factors that can degrade the overall brightness uniformity. For example, differences in the threshold voltage of the transistor elements in the pixel circuit, differences in the chromaticity of the LED, differences in the voltage drop (IR drop), or the carrier mobility of the transistor elements may make the overall brightness of the display uneven. Currently, sub-millimeter LEDs are compensated using internal circuitry, but there are still many problems with this approach. For example, for the overall circuit, there is no way to know which pixel circuit has an anomalous LED; for individual pixel circuits, only the threshold voltage of the transistor element can be compensated and the range of compensation is limited; and the complexity of the compensation circuit is prone to differences due to process factors.
According to an embodiment of the disclosure, an electronic device includes a first driving circuit, a processor, and a data driver. The first driving circuit is configured to receive a first driving signal and generate a sensing signal. The data driver is coupled to the first driving circuit and the processor. An operation period of the electronic device includes a first detection phase and a compensation phase. The compensation phase is after the first detection phase. In the first detection phase, the data driver provides the first driving signal to the first driving circuit and receives the sensing signal from the first driving circuit. The processor calculates a first compensation value corresponding to the first driving circuit based on the sensing signal. In the compensation phase, the data driver generates a second driving signal based on the first compensation value and provides the second driving signal to the first driving circuit.
According to an embodiment of the disclosure, an electronic device includes a substrate, multiple electronic elements, multiple driving circuits, multiple scan lines, and a data driver. The electronic elements are disposed on the substrate and arranged in an array. The driving circuit is installed on the substrate and corresponding to the electronic elements. One of the driving circuits is configured to receive a driving signal to drive one of the electronic elements and generate a sensing signal. The scan lines are disposed on the substrate and coupled to the driving circuit. The scan lines are configured to provide multiple scan signals to the driving circuit. The data driver is coupled to one of the driving circuits. The data driver is configured to provide a driving signal and receive a sensing signal. The array includes N rows, and a number of the scan lines is N+1.
To make the aforementioned more comprehensible, several embodiments accompanied with drawings are described in detail as follows.
The accompanying drawings are included to provide a further understanding of the disclosure, and are incorporated in and constitute a part of this specification. The drawings illustrate example embodiments of the disclosure and, together with the description, serve to explain the principles of the disclosure.
The disclosure can be understood by referring to the following detailed description in conjunction with the accompanying drawings. It should be noted that, in order to make it easy for the reader to understand and for the simplicity of the drawings, many of the drawings in the disclosure only depict a part of the electronic device. And certain elements in the drawings are not drawn to actual scale. In addition, the number and size of each element in the figures are only for illustration and are not intended to limit the scope of the disclosure.
In the following description and claims, the words “include” and “comprise” are open-ended words, and therefore they should be interpreted to mean “includes but is not limited to . . . ”.
It should be understood that although the terms first, second, third . . . can be used to describe various constituent elements, the constituent elements are not limited to these terms. These terms are only used to distinguish a single component from other components in the specification. The same terms may not be used in the claims, but may be replaced by first, second, third . . . according to the order in which the elements are declared in the claims. Therefore, in the following description, the first component may be the second component in the claims.
In some embodiments of the disclosure, terms related to joining and connecting, such as “connected”, “interconnected”, etc., unless otherwise defined, may mean that two structures are in direct contact, or may also mean that two structures are not in direct contact, there are other structures located between these two structures. And the terms about joining and connecting can also include the situation where both structures are movable, or both structures are fixed. In addition, the term “coupling” includes any direct and indirect means of electrical connection. In the case of direct electrical connection, the end points of the elements on two circuits are directly connected or connected to each other with a conductor line segment. In the case of indirect electrical connection, there is a switch, diode, capacitor, inductor, resistor, other suitable element, or a combination of the foregoing, between the end points of the elements on the two circuits, but are not limited thereto.
An electronic device of the disclosure may include a display device, an antenna device, a sensing device, a light emitting device, or a splicing device, but is not limited thereto. The electronic device may include a bendable or flexible electronic device. The electronic device may include an electronic element. The electronic device includes, for example, a liquid crystal layer or a light emitting diode (LED). The electronic element can include a passive element and an active element, such as a capacitor, resistor, inductor, variable capacitor, filter, diode, transistor, sensor, microelectromechanical systems (MEMS), liquid crystal chip, controller, etc., but not limited thereto. The Diode may include a light emitting diode or photodiode. The light emitting diode may include, for example, organic light emitting diode (OLED), sub-millimeter light emitting diode (mini-LED), micro light emitting diode (micro-LED), quantum dot LED, fluorescence, phosphor, or other suitable material, or a combination of the above, but not limited thereto. The sensor may include, for example, a capacitive sensor, optical sensor, electromagnetic sensor, fingerprint sensor (FPS), touch sensor, antenna, or pen sensor, etc., but not limited thereto. The controller may include, for example, a timing controller, but is not limited thereto. In the following, the disclosure is illustrated by using a display device as an electronic device, but the disclosure is not limited thereto.
Reference will now be made in detail to the exemplary embodiments of the disclosure, examples of which are illustrated in the accompanying drawings. Whenever possible, the same reference numbers are used in the drawings and descriptions to refer to the same or similar parts.
The pixel circuits 112 are disposed on the substrate 110 and arranged in an array. The array includes N rows and M columns, and a number of the scan lines 116 is N+1, where N and M are integers greater than 1. The pixel circuit 112 may be a pixel that emits multiple colors of light at the same time, or a sub-pixel that emits a single color of light. The pixel circuit 112 includes an electronic element 210 and a driving circuit 220. The electronic element 210 is disposed on the substrate 110 and arranged in an array. The electronic element 210 may include multiple light emitting elements or a single light emitting element. In
In
The data driver 120 is coupled to the driving circuit 220 and the processor 130. The data driver 120 receives original data signals D10 to DM0, that is, uncompensated data signals. In
The data driver 120 includes multiple output circuits 122 and multiple sensing circuits 124. An output circuit 122 is used to output the driving signals D1 to DM to a data line 114. The driving signals D1 to DM may be, for example, but not limited to, compensated data signals. The output circuit 122 may include a digital-to-analog converter for converting digital data into analog driving signals D1 to DM, but is not limited thereto. The sensing circuit 124 is coupled to a sensing line 115 for transmitting the sensing signals S1 to SM, and is used to receive the sensing signals S1 to SM. The sensing circuit 124 may include an analog-to-digital converter, which may be used (but is not limited to) to convert the sensing signals S1 to SM into digital signals, and output conversion values V1, V2 to VM to the processor 130.
The processor 130 receives the conversion values V1 to VM, calculates and outputs the compensation values C1 to CM to the data driver 120 accordingly. In addition, the processor 130 can also determine whether the electronic element 210 in the pixel circuit 112 is anomalous. For example, the processor 130 can determine whether a brightness of the electronic element 210 deviates too much from the overall brightness uniformity of the substrate 110 based on the conversion values V1 to VM, such as being too bright or too dark, and is therefore determined to be an anomalous element.
Specifically, the first detection phase 310 includes multiple frame times FT1 and FT2. At the frame time FT1, the scan driver 140 sequentially provides scan signals G1, G2, G3 to GN, G(N+1) through the scan lines 116 to the each driving circuit 220 on the mth column, and turns on the transistor element T2 therein. Next, at the frame time FT1, the data driver 120 provides a first driving signal Dm1 with a voltage value VT0, and sequentially drives a transistor element T1 of the each driving circuit 220. Moreover, taking the driving circuit 220 of the nth row shown in
At the frame time FT2, the detection method is similar to the frame time FT1, except that the data driver 120 provides a first driving signal Dm2 with a voltage value VT1 to drive the each driving circuit 220 on the mth column, where the voltage value VT1 is greater than the voltage value VT0. That is, in this embodiment, the voltage values VT0 and VT1 of the first driving signals Dm1 and Dm2 may gradually increase with different frame times FT1 and FT2, but the disclosure is not limited thereto. In some embodiments, the voltage values VT0 and VT1 of the first driving signals Dm1 and Dm2 may gradually decrease with different frame times FT1 and FT2. In addition, a blank period BLK may be included between two adjacent frame times FT1 and FT2, but for the sake of simplicity, it is not shown in
Specifically, the compensation phase 320 includes multiple frame times FT1 and FT2. At the frame time FT1, the scan driver 140 sequentially provides scan signals G1, G2, G3 to GN, G(N+1) through the scan lines 116 to the each driving circuit 220 on the mth column, and turns on the transistor element T2 therein. In the frame time FT1, the data driver 120 provides a second driving signal Dm1′ and drives the transistor element T1 of the each driving circuit 220 sequentially. At the frame time FT2, the compensation method is similar to the frame time FT1, except that the data driver 120 provides the second driving signal Dm2′ to drive the each driving circuit 220 on the mth column.
In this embodiment, the voltage values of the second driving signals Dm1′ and Dm2′ are equal to voltage values of original data signals Dm01 and Dm02 plus the compensation value Cm obtained in the first detection phase 310. Specifically, the driving circuit 220 on the mth column includes, for example, a first driving circuit 220_1, a second driving circuit 220_2, and a third driving circuit 220_3. In the first detection phase 310, taking the frame time FT1 as an example, the data driver 120 provides the first driving signal Dm to the first driving circuit 220_1, the second driving circuit 220_2, and the third driving circuit 220_3 to obtain a first compensation value Cm1 corresponding to the first driving circuit 220_1, a second compensation value Cm2 corresponding to the second driving circuit 220_2, and a third compensation value Cm3 corresponding to the third driving circuit 220_3. In the compensation phase 320, taking the frame time FT1 as an example, a second driving signal 510 used to drive the first driving circuit 220_1 is equal to a voltage value of a corresponding original data signal 510A in
In this embodiment, the first compensation value Cm1, the second compensation value Cm2, and the third compensation value Cm3 are all the same, but this disclosure is not limited thereto. That is, in this embodiment, the compensation value of each driving circuit may be determined according to the characteristic curve of the electronic element, the processor 130 calculates a representative compensation value based on the respective compensation value, and the entire screen is then compensated with this representative value. In other embodiments, the first compensation value Cm1, the second compensation value Cm2, and the third compensation value Cm3 may also be different. Or the first compensation value Cm1 and the second compensation value Cm2 are the same, and the first compensation value Cm1 and the third compensation value Cm3 are different. The disclosure does not limit the relationship between the magnitude of the compensation values of the each driving circuit.
In the embodiments of
At the time of leaving the factory, each pixel circuit 112 of the electronic device 100 may be measured first to obtain an original characteristic curve 910 of the electronic element 210. For example, the original characteristic curve 910 of each electronic element 210 is obtained when the overall brightness uniformity of the electronic device 100 is 90% or more, but the criteria for obtaining the original characteristic curve in the disclosure are not limited thereto. Then, the first detection phase 310 is a first measurement performed when the device is powered on. As shown in
Next, the processor 130 may compare the characteristic curves 910 and 920, calculate an offset 930 of the characteristic curve 910, and determine the compensation value Cm. The offset 930 may be calculated by obtaining two signal values VD01 and VD1 on the two curves 910 and 920 corresponding to a same end voltage value Y1, and the difference between the two signal values VD0 and VD1 is the offset 930. In this embodiment, the end voltage value Y1 may correspond to (but is not limited to) turning points P01 and P1 of the characteristic curves 910 and 920. Thus, the offset 930 is the offset of the turning points P01 and P1 of the curves. In an embodiment, the offset may also be determined by an average of offsets of multiple points on the curve. This disclosure places no restrictions on how the offset is calculated.
In addition, the processor 130 may also set a threshold. When the offset exceeds the threshold, the processor 130 determines that the electronic element 210 is anomalous, such as being in an open circuit or short circuit state. At this time, the data driver 120 provides a driving signal corresponding to 0 gray level to the driving circuit 220 corresponding to the anomalous electronic element 210.
After obtaining the offset 930 corresponding to the each driving circuit 220 in the first detection phase 310, the compensation value Cm used in the compensation phase 330 may be determined according to the corresponding method of the embodiment of
Similarly, the compensation value Cm generated after the second detection phase 320 may be determined according to the corresponding method of the embodiments of
In an embodiment, when the electronic device 100 achieves the preset brightness uniformity in the compensation phase, the electronic device 100 may only detect in the next detection phase without compensating in the next compensation phase. In an embodiment, the electronic device 100 may gradually adjust the driving signal in the frame times FT during the compensation phase, and the adjustment of the compensation value is accomplished gradually over a number of times rather than immediately all at once to minimize the situation where the voltage adjustment of the drive signal is too large and affects the display quality.
Specifically, taking the each driving circuit 220 on the mth column as an example, the scan lines 116 may be divided into multiple scan line groups. A scan signal GP1 is the scan signal GP1 used to scan a first scan line group, and scan signals GP2, GP3, and GPK are scan signals used to scan a second scan line group, a third scan line group, and a Kth scan line group, where K is an integer greater than 3. Taking the first scan line group as an example, in a first section 1110_1, the scan signal GP1 sequentially scans the scan lines, and the data driver 120 provides the second driving signal Dm′ to the driving circuit 220 for display purposes. Then, in a second section 1120_1, the data driver 120 provides the first driving signal Dm to the driving circuit 220 for testing purposes. In a second section 1110_2, a corresponding driving circuit 220 outputs the sensing signal Sm to the data driver 120. The detection methods of other scan line groups may be deduced in the same way. In this way, the scan driver 140 may complete scanning by grouping in less than the frame time FT required in the previous embodiment, and the data driver 120 and the processor 130 may complete the detection operation and compensation operation.
It should be noted that although a waveform corresponding to the last scanning group GPK in
In this embodiment, in order to minimize the user's perception of a delay due to detection, a frame time may be divided into multiple sections by a multitasker circuit during any of the detection phases. Detection is performed after each part of the scanning line is turned on. If detection is performed in this manner, since a new compensation value has not yet been decided upon, the compensation is still displayed in the current state, such as using the original data signal or using the old compensation value.
To sum up, in the embodiments of the disclosure, the operation period of the electronic device includes a detection phase and a compensation phase. In each detection phase, the processor calculates the compensation value, so that in the next compensation phase, the data driver compensates the driving circuit based on the compensation value. In this way, the overall brightness uniformity of the electronic device may be improved. In addition, in the detection phase, in order to continuously display the screen, the data driver may alternately output the driving signal for detection and the driving signal for display to drive the driving circuit.
It will be apparent to those skilled in the art that various modifications and variations can be made to the disclosed embodiments without departing from the scope or spirit of the disclosure. In view of the foregoing, it is intended that the disclosure covers modifications and variations provided that they fall within the scope of the following claims and their equivalents.
| Number | Date | Country | Kind |
|---|---|---|---|
| 202311656450.1 | Dec 2023 | CN | national |