OLED product brightness difference improvement system and method

Abstract

The invention discloses an OLED product brightness difference improvement system and method, and relates to the field of brightness compensation, and the system comprises a flexible circuit board and a driving chip. The flexible circuit board is used for connecting different jigs after leaving a factory, acquiring a current driving voltage signal and a current feedback voltage signal when the OLED product is lightened by adopting the current jig, sending the current driving voltage signal to the OLED product, and sending the current feedback voltage signal to the driving chip; the driving chip is used for detecting a current driving voltage signal through a current feedback voltage signal, calculating a voltage difference value according to the detected current driving voltage signal and a pre-stored given driving voltage signal, and compensating an output voltage by adopting the voltage difference value, and the compensated output voltage is used for adjusting a grid voltage of the first driving tube; according to the invention, the brightness difference of the OLED product can be rapidly improved, and the power consumption of the product is reduced.

Description

Technical Field

[0001] The present application relates to the field of brightness compensation, and in particular to a system and method for improving brightness differences of OLED products. Background Art

[0002] Different fixtures have different power drive capabilities, resulting in different brightness of silicon-based organic light-emitting diode (OLED) products when lit by different fixtures, affecting product production testing and terminal display effects. The related brightness difference improvement solution compensates the Vcom voltage through hardware or software of the product peripheral circuit (FPC / PCB), which requires the sampling process of the peripheral circuit, has a slow compensation rate, and the product consumes a lot of power. Summary of the invention

[0003] The purpose of this application is to provide a system and method for improving the brightness difference of OLED products, which can achieve rapid improvement of the brightness difference of OLED products and reduce product power consumption.

[0004] To achieve the above objectives, this application provides the following solutions:

[0005] In a first aspect, the present application provides an OLED product brightness difference improvement system, which is used for an OLED product; the OLED product comprises: a first driving tube, a second driving tube, a third driving tube and a light emitting diode; the OLED product brightness difference improvement system comprises: a flexible circuit board and a driving chip;

[0006] The flexible circuit board is connected to the driving chip; the driving chip is connected to the gate and source of the second driving tube and the gate and source of the third driving tube; the drain of the second driving tube and the drain of the third driving tube are both connected to the gate of the first driving tube; the source of the first driving tube is connected to the positive electrode of the light-emitting diode; the negative electrode of the light-emitting diode is connected to the flexible circuit board;

[0007] The flexible circuit board is used to connect different fixtures after leaving the factory, and obtain the current driving voltage signal and the current feedback voltage signal when the current fixture is used to light up the OLED product, and send the current driving voltage signal to the OLED product, and send the current feedback voltage signal to the driving chip;

[0008] The driving chip is used to detect the current driving voltage signal through the current feedback voltage signal, and calculate the voltage difference based on the detected current driving voltage signal and the given driving voltage signal stored in advance, and use the voltage difference to compensate the output voltage. The compensated output voltage is used to adjust the gate voltage of the first driving tube so that the brightness of the light-emitting diode reaches the set brightness value.

[0009] Optionally, the flexible circuit board is also used to obtain a given driving voltage signal and a given feedback voltage signal during debugging before delivery, and send the given driving voltage signal to the OLED product, and send the given feedback voltage signal to the driving chip;

[0010] The driver chip is also used to detect a given driving voltage signal through a given feedback voltage signal, and generate an output voltage according to the detected given driving voltage signal, to provide a gate voltage for the first driving tube, so that the brightness of the light-emitting diode reaches a set brightness value.

[0011] Optionally, in calculating the voltage difference according to the detected current driving voltage signal and the pre-stored given driving voltage signal, the driving chip is specifically used for:

[0012] The voltage difference is calculated using the formula ΔVcom=Vcom_0-Vcom_1, wherein ΔVcom represents the voltage difference; Vcom_0 represents a given driving voltage signal stored in advance; and Vcom_1 represents the current driving voltage signal.

[0013] Optionally, in terms of using the voltage difference to compensate the output voltage, the driver chip is specifically used for:

[0014] Calculating a compensation voltage according to the voltage difference and the amplification factor of the first driving tube;

[0015] The compensation voltage is fed back to the output voltage of the driver chip to obtain a compensated output voltage.

[0016] Optionally, in calculating the compensation voltage according to the voltage difference and the amplification factor of the first driving tube, the driving chip is specifically used for:

[0017] The compensation voltage is calculated using the formula ΔV=ΔVcom / N, wherein ΔV represents the compensation voltage; ΔVcom represents the voltage difference; and N represents the amplification factor of the first driving tube.

[0018] Optionally, in terms of feeding back the compensation voltage to the output voltage of the driver chip to obtain the compensated output voltage, the driver chip is specifically used for:

[0019] The output voltage after compensation is calculated using the formula Vdata1=Vdata+ΔV; wherein Vdata1 represents the output voltage after compensation; Vdata represents the output voltage before compensation; and ΔV represents the compensation voltage.

[0020] Optionally, the calculation formula of the amplification factor of the first driving tube is: N=Va / Vg; Va represents the source voltage of the first driving tube; Vg represents the gate voltage of the first driving tube.

[0021] Optionally, the amplification factor of the first driving tube is 0.5, 0.6 or 0.8.

[0022] In a second aspect, the present application provides a method for improving brightness differences of OLED products, the method for improving brightness differences of OLED products being used in the above-mentioned system for improving brightness differences of OLED products, the method for improving brightness differences of OLED products comprising:

[0023] Get the current feedback voltage signal when the current fixture is used to light up the OLED product;

[0024] Detecting the current driving voltage signal through the current feedback voltage signal;

[0025] Calculating a voltage difference according to a detected current driving voltage signal and a pre-stored given driving voltage signal;

[0026] The voltage difference is used to compensate the output voltage, and the compensated output voltage is used to adjust the gate voltage of the first driving tube so that the brightness of the light-emitting diode reaches a set brightness value.

[0027] Optionally, the method for improving brightness difference of OLED products further includes:

[0028] During the debugging before delivery, obtain the given feedback voltage signal;

[0029] Detecting a given driving voltage signal through a given feedback voltage signal;

[0030] An output voltage is generated according to the detected given driving voltage signal, and a gate voltage is provided for the first driving tube, so that the brightness of the light emitting diode reaches a set brightness value.

[0031] According to the specific embodiments provided in this application, this application has the following technical effects:

[0032] The present application provides a system and method for improving the brightness difference of an OLED product. The system includes: a flexible circuit board and a driver chip. When connecting different fixtures, the driver chip detects a current driving voltage signal by acquiring a current feedback voltage signal of the flexible circuit board, and calculates a voltage difference according to the detected current driving voltage signal and a given driving voltage signal stored in advance, and uses the voltage difference to compensate the output voltage. The compensated output voltage is used to adjust the gate voltage of a first driving tube so that the brightness of the light-emitting diode reaches a set brightness value. When different fixtures light up the OLED product, the present application does not require a sampling process to compensate the Vcom voltage to improve the brightness of the OLED product, but keeps the Vcom voltage unchanged, and improves the brightness of the OLED product by compensating the gate voltage of the first driving tube, which not only achieves a rapid improvement in the brightness difference of the OLED product, but also reduces the power consumption of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0034] Figure 1 A structural diagram of a system for improving brightness differences of OLED products provided in one embodiment of the present application;

[0035] Figure 2 A schematic diagram of a process for improving brightness differences of OLED products provided in another embodiment of the present application;

[0036] Figure 3 The compensation principle diagram of the prior art solution;

[0037] Figure 4 This is the compensation principle diagram of this application. DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0039] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0040] See also Figure 1The present application provides an OLED product brightness difference improvement system, and the OLED product brightness difference improvement system is used for OLED products. The OLED product is a silicon-based OLED product. The OLED product includes: a first drive tube M1, a second drive tube M2, a third drive tube M3 and a light-emitting diode. The OLED product brightness difference improvement system includes: a flexible printed circuit (Flexible Printed Circuit, FPC) and a driver chip (Driver IC, DIC).

[0041] The flexible circuit board is connected to the driving chip; the driving chip is connected to the gate and source of the second driving tube M2 and the gate and source of the third driving tube M3; the drain of the second driving tube M2 and the drain of the third driving tube M3 are both connected to the gate of the first driving tube M1; the source of the first driving tube M1 is connected to the positive electrode of the light-emitting diode; and the negative electrode of the light-emitting diode is connected to the flexible circuit board.

[0042] The flexible circuit board is used to connect different fixtures after leaving the factory, and obtain the current driving voltage signal and the current feedback voltage signal when the current fixture is used to light up the OLED product, and send the current driving voltage signal to the OLED product and the current feedback voltage signal to the driver chip.

[0043] The driving chip is used to detect the current driving voltage signal through the current feedback voltage signal, and calculate the voltage difference according to the detected current driving voltage signal and the given driving voltage signal stored in advance, and use the voltage difference to compensate the output voltage. The compensated output voltage is used to adjust the gate voltage of the first driving tube M1 so that the brightness of the light-emitting diode reaches the set brightness value.

[0044] In another exemplary embodiment of the present application, the flexible circuit board is also used to obtain a given driving voltage signal and a given feedback voltage signal during debugging before leaving the factory, and send the given driving voltage signal to the OLED product, and send the given feedback voltage signal to the driving chip.

[0045] The driver chip is also used to detect a given driving voltage signal through a given feedback voltage signal, and generate an output voltage according to the detected given driving voltage signal, to provide a gate voltage for the first driving tube M1, so that the brightness of the light-emitting diode reaches a set brightness value.

[0046] In another exemplary embodiment of the present application, the driving chip includes: a voltage detection module, a difference calculation module and a voltage compensation module.

[0047] The voltage detection module is used to detect the current driving voltage signal through the current feedback voltage signal; the difference calculation module is used to calculate the voltage difference based on the detected current driving voltage signal and the pre-stored given driving voltage signal; the voltage compensation module is used to compensate the output voltage using the voltage difference.

[0048] The difference calculation module includes: a voltage difference calculation unit, which is used to calculate the voltage difference using the formula ΔVcom=Vcom_0-Vcom_1; wherein ΔVcom represents the voltage difference; Vcom_0 represents a pre-stored given driving voltage signal; and Vcom_1 represents a current driving voltage signal.

[0049] The voltage compensation module includes: a compensation voltage calculation unit, which is used to calculate the compensation voltage according to the voltage difference and the amplification factor of the first driving tube M1. Specifically: the compensation voltage is calculated using the formula ΔV=ΔVcom / N; wherein ΔV represents the compensation voltage; ΔVcom represents the voltage difference; and N represents the amplification factor of the first driving tube M1.

[0050] The calculation formula of the amplification factor of the first driving tube M1 is: N=Va / Vg; Va represents the source voltage of the first driving tube M1; Vg represents the gate voltage of the first driving tube M1. The amplification factor of the first driving tube M1 can be 0.5, 0.6 or 0.8.

[0051] The digital-to-analog conversion unit (DAC) is used to feed back the compensation voltage to the output voltage of the driver chip to obtain the compensated output voltage. Specifically, the compensated output voltage is calculated using the formula Vdata1=Vdata+ΔV; wherein Vdata1 represents the compensated output voltage; Vdata represents the output voltage before compensation; ΔV represents the compensation voltage.

[0052] In another exemplary embodiment of the present application, please refer to Figure 1 , the cathode of the light-emitting diode in the OLED product is connected to the flexible circuit board through a cathode ring. The driving chip also includes: a row driving module; the digital-to-analog conversion unit in the driving chip is connected to the column driving signal line COL_x of the OLED product, the source of the second driving tube M2 and the source of the third driving tube M3 are both connected to the column driving signal line COL_x, the gate of the second driving tube M2 is connected to the first row driving signal line ROW_y, and the gate of the third driving tube M3 is connected to the second row driving signal line ROWB_y.

[0053] In practical applications, an implementation process of the OLED product brightness difference improvement system of this embodiment is as follows:

[0054] (1) When debugging the product before shipment, a given driving voltage signal Vcom_0 is provided to the cathode ring of the OLED product through the flexible circuit board, and a given feedback voltage signal Vcom_sen0 is input to the driving chip.

[0055] (2) During Gamma debugging, the driving voltage signal Vcom is detected and recorded through Vcom_sen0 and saved in the driving chip.

[0056] (3) When the OLED product is illuminated by another fixture after leaving the factory, the driver chip detects the current driving voltage signal Vcom_1 of the fixture through the current feedback voltage signal Vcom_sen1, and calculates the voltage difference ΔVcom=Vcom_0-Vcom_1.

[0057] (4) The compensation voltage ΔV=ΔVcom / N is calculated and fed back to the output voltage Vdata of the digital-to-analog conversion unit to obtain the compensated output voltage Vdata1=Vdata+ΔV, thereby achieving the regulation of the gate voltage of the first driving tube M1.

[0058] It can be seen that according to Figure 1 In the pixel driving circuit (source follower) shown, after adjusting the gate voltage of the first driving tube M1, the anode voltage (M1 source) of the OLED product will also change accordingly, thereby compensating for the brightness effect caused by the Vcom difference.

[0059] In practical applications, taking 500 nit brightness as an example, the calculation process of the amplification factor N of the first driving tube M1 and the gate voltage compensation process are described.

[0060] The calculation process of N: According to the OLED simulation (or test) and the Vcom voltage, the anode voltage of the 500nit OLED device, that is, the source voltage Va of the first driving tube M1, is calculated; through Gamma debugging, the Vdata output by the 500nit DAC, that is, the gate voltage Vg of the first driving tube M1, is calculated; the amplification factor N of the first driving tube M1 is determined according to the formula N=Va / Vg.

[0061] Gate voltage compensation process: The Gamma site records 500nitVcom voltage and saves it in the driver chip; the driver chip detects the new drive voltage signal Vcom_1 through Vcom_sen1; the driver chip calculates the voltage difference ΔVcom=Vcom_0-Vcom_1; the digital-to-analog conversion unit in the driver chip adjusts the output voltage to obtain the compensated output voltage Vdata1=Vdata+ΔVcom / N.

[0062] Based on the same inventive concept, the embodiment of the present application also provides a method for improving the brightness difference of OLED products implemented by the above-mentioned system for improving the brightness difference of OLED products. The implementation scheme for solving the problem provided by the method is similar to the implementation scheme recorded in the above-mentioned system, so the specific limitations in one or more embodiments of the method for improving the brightness difference of OLED products provided below can refer to the limitations of the system for improving the brightness difference of OLED products above, and will not be repeated here.

[0063] In an exemplary embodiment, Figure 2 As shown, the method for improving brightness difference of OLED products includes:

[0064] Step 201, obtaining a current feedback voltage signal when the current fixture is used to light up the OLED product.

[0065] Step 202: Detect the current driving voltage signal through the current feedback voltage signal.

[0066] Step 203: Calculate a voltage difference according to the detected current driving voltage signal and a pre-stored given driving voltage signal.

[0067] Step 204: The voltage difference is used to compensate the output voltage, and the compensated output voltage is used to adjust the gate voltage of the first driving tube M1 so that the brightness of the light emitting diode reaches the set brightness value.

[0068] As an optional implementation, the method for improving brightness differences of OLED products also includes: obtaining a given feedback voltage signal during debugging before leaving the factory; detecting a given driving voltage signal through the given feedback voltage signal; generating an output voltage according to the detected given driving voltage signal, and providing a gate voltage for the first driving tube M1, so that the brightness of the light-emitting diode reaches a set brightness value.

[0069] This application improves the driving scheme for brightness differences of different fixtures of silicon-based OLED products. By detecting the difference in Vcom voltage output of different fixtures, the compensation value of the gate voltage of the driving tube is calculated, and then the anode voltage of the OLED is compensated, so that the anode and cathode voltage difference of the OLED product remains close to the same, that is, the brightness of the silicon-based OLED product remains close to the same, achieving the purpose of improving the brightness difference of the product when different fixtures are lit and improving the display effect of the product.

[0070] The advantages of the method and system for improving brightness difference of OLED products of the present application are described below by comparing with the method of dynamically adjusting the Vcom voltage.

[0071] See also Figure 3The existing technical solution compensates the Vcom voltage through the hardware or software of the product peripheral circuit (FPC / PCB). This solution requires the sampling process of the peripheral circuit and the compensation rate is slow; see Figure 4 The embodiment of the present application is implemented by compensating the gate voltage of the first driving tube M1. In this way, the Vcom voltage remains unchanged, which further saves product power consumption.

[0072] The technical features of the above embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0073] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. At the same time, for those skilled in the art, according to the ideas of this application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting this application.

Claims

1. A system for improving brightness difference of OLED products, characterized in that: The OLED product brightness difference improvement system is used for OLED products; The OLED product includes: a first driving tube, a second driving tube, a third driving tube and a light emitting diode; the OLED product brightness difference improvement system includes: a flexible circuit board and a driving chip; The flexible circuit board is connected to the driving chip; the driving chip is connected to the gate and source of the second driving tube and the gate and source of the third driving tube; the drain of the second driving tube and the drain of the third driving tube are both connected to the gate of the first driving tube; the source of the first driving tube is connected to the positive electrode of the light-emitting diode; the negative electrode of the light-emitting diode is connected to the flexible circuit board; The flexible circuit board is used to connect different fixtures after leaving the factory, and obtain the current driving voltage signal and the current feedback voltage signal when the current fixture is used to light up the OLED product, and send the current driving voltage signal to the OLED product, and send the current feedback voltage signal to the driving chip; The driving chip is used to detect the current driving voltage signal through the current feedback voltage signal, and calculate the voltage difference based on the detected current driving voltage signal and the given driving voltage signal stored in advance, and use the voltage difference to compensate the output voltage. The compensated output voltage is used to adjust the gate voltage of the first driving tube so that the brightness of the light-emitting diode reaches the set brightness value.

2. The OLED product brightness difference improvement system according to claim 1, characterized in that: The flexible circuit board is also used to obtain a given driving voltage signal and a given feedback voltage signal during debugging before delivery, and send the given driving voltage signal to the OLED product and send the given feedback voltage signal to the driving chip; The driver chip is also used to detect a given driving voltage signal through a given feedback voltage signal, and generate an output voltage according to the detected given driving voltage signal, to provide a gate voltage for the first driving tube, so that the brightness of the light-emitting diode reaches a set brightness value.

3. The OLED product brightness difference improvement system according to claim 1, characterized in that: In terms of calculating the voltage difference according to the detected current driving voltage signal and the pre-stored given driving voltage signal, the driving chip is specifically used for: The voltage difference is calculated using the formula ΔVcom=Vcom_0-Vcom_1, wherein ΔVcom represents the voltage difference; Vcom_0 represents a given driving voltage signal stored in advance; and Vcom_1 represents the current driving voltage signal.

4. The OLED product brightness difference improvement system according to claim 1, characterized in that: In terms of using the voltage difference to compensate the output voltage, the driver chip is specifically used for: Calculating a compensation voltage according to the voltage difference and the amplification factor of the first driving tube; The compensation voltage is fed back to the output voltage of the driver chip to obtain a compensated output voltage.

5. The OLED product brightness difference improvement system according to claim 4, characterized in that: In terms of calculating the compensation voltage according to the voltage difference and the amplification factor of the first driving tube, the driving chip is specifically used for: The compensation voltage is calculated using the formula ΔV=ΔVcom / N, wherein ΔV represents the compensation voltage; ΔVcom represents the voltage difference; and N represents the amplification factor of the first driving tube.

6. The OLED product brightness difference improvement system according to claim 4, characterized in that: In terms of feeding back the compensation voltage to the output voltage of the driver chip to obtain the compensated output voltage, the driver chip is specifically used for: The output voltage after compensation is calculated using the formula Vdata1=Vdata+ΔV; wherein Vdata1 represents the output voltage after compensation; Vdata represents the output voltage before compensation; and ΔV represents the compensation voltage.

7. The OLED product brightness difference improvement system according to claim 5, characterized in that: The calculation formula of the amplification factor of the first driving tube is: N=Va / Vg; Va represents the source voltage of the first driving tube; Vg represents the gate voltage of the first driving tube.

8. The OLED product brightness difference improvement system according to claim 7, characterized in that: The amplification factor of the first driving tube is 0.5, 0.6 or 0.

8.

9. A method for improving brightness difference of OLED products, characterized in that: The method for improving brightness difference of OLED products is used in the system for improving brightness difference of OLED products according to any one of claims 1 to 8, and the method for improving brightness difference of OLED products comprises: Get the current feedback voltage signal when the current fixture is used to light up the OLED product; Detecting the current driving voltage signal through the current feedback voltage signal; Calculating a voltage difference according to a detected current driving voltage signal and a pre-stored given driving voltage signal; The voltage difference is used to compensate the output voltage, and the compensated output voltage is used to adjust the gate voltage of the first driving tube so that the brightness of the light-emitting diode reaches a set brightness value.

10. The method for improving brightness difference of OLED products according to claim 9, characterized in that: The method for improving brightness difference of OLED products also includes: During the debugging before delivery, obtain the given feedback voltage signal; Detecting a given driving voltage signal through a given feedback voltage signal; An output voltage is generated according to the detected given driving voltage signal, and a gate voltage is provided for the first driving tube, so that the brightness of the light emitting diode reaches a set brightness value.

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