OLED display device and brightness compensation device and method thereof

Abstract

The present invention discloses an OLED display device and a brightness compensation device and method thereof. The brightness compensation method comprises: dividing a display panel into a plurality of display areas; testing pixel units in the plurality of display areas to obtain an L-V characteristic curve; adjusting a first supply voltage of the pixel units in the plurality of display areas according to the L-V characteristic curve, so that the display brightness of OLEDs in the plurality of display areas after aging is consistent, overcoming the brightness difference between the areas that may be generated when the picture track moves, and achieving consistent display brightness of all areas in the OLED display device.

Description

Technical Field

[0001] The present invention relates to the field of display technology, and in particular to an OLED display device and a brightness compensation device and method thereof. Background Art

[0002] With the development of technology, the number of TV products equipped with OLED screens has gradually increased. OLED screens are particularly sensitive to light-emitting devices, and the material properties of OLED aging have always been an insurmountable problem. Since OLED is an independent light-emitting device, each pixel may age at different speeds due to differences in the display screen, which leads to the problem of image retention. Once image retention occurs, the entire screen cannot meet the needs of use, and OLED screens are generally very expensive, so some processing needs to be done on the OLED screen display to increase the service life of the OLED screen.

[0003] like Figure 1a As shown in the figure, the existing processing method is to add additional pixels in addition to the supported resolution, and slightly move the display screen after a fixed time to disperse the display time of each pixel, which is generally called the orbit function. Figure 1a In the normal display resolution of 1600x1200, and the total screen resolution of 1632x1228, while maintaining the 1600x1200 display screen, the graphics are moved randomly or in a fixed track to disperse the aging time of each pixel in the screen, thereby increasing the service life of the OLED screen. However, if Figure 1b As shown, this method will increase the pixel display pressure in the moving overlapping area for engineering graphics, such as white images, and will instead cause aging, causing the screen brightness to present multiple uneven display blocks, affecting the user's viewing experience. Summary of the invention

[0004] In view of the above problems, an object of the present invention is to provide an OLED display device and a brightness compensation device and method thereof, so as to solve the above-mentioned technical defects.

[0005] According to one aspect of the present invention, there is provided a brightness compensation method for an OLED display device, comprising:

[0006] Dividing the display panel into a plurality of display areas;

[0007] Testing pixel units in the plurality of display areas to obtain LV characteristic curves;

[0008] The first supply voltages of the pixel units in the plurality of display areas are adjusted according to the LV characteristic curve, so that the display brightness of the OLEDs in the plurality of display areas after aging is consistent.

[0009] Optionally, when the picture track moves, the multiple display areas are distinguished according to the OLED display duration in the display panel.

[0010] Optionally, the plurality of display areas are respectively a picture overlap area, a transition area and a pixel movement area from inside to outside,

[0011] Wherein, the transition area is located between the picture overlap area and the pixel movement area;

[0012] The picture overlap area is the area where the OLED is always in display state when the picture track moves;

[0013] The pixel moving area is an area in the display panel that expands outward for the movement of the picture track.

[0014] Optionally, the centers of the picture overlap area, the transition area and the pixel shift area are consistent, the transition area and the pixel shift area are in a U-shape, and the distances between the outer edges and the inner edges of the two are the same.

[0015] Optionally, the LV characteristic curve includes: LV characteristic curves of the OLEDs in the multiple display areas after aging or LV characteristic curves of the OLEDs in the multiple display areas before and after aging.

[0016] Optionally, it also includes: taking the brightness of the OLEDs in the multiple display areas when working normally before aging as a reference brightness value, and adjusting the first supply voltage of the pixel units in the multiple display areas until the display brightness of the OLEDs in the multiple display areas after aging is consistent with the reference brightness value.

[0017] Optionally, it also includes taking the brightness of the OLED in the overlapping area of ​​the picture when working normally after aging as a reference brightness value, and adjusting the first supply voltage of the pixel unit in other areas until the display brightness of the OLED in the other display area after aging is consistent with the reference brightness value.

[0018] Optionally, the testing the pixel units in the multiple display areas to obtain the LV characteristic curve includes: measuring and calculating the brightness value of the tested pixel under different first supply voltages for any pixel unit in the multiple display areas.

[0019] According to another aspect of the present invention, a brightness compensation device is provided, comprising: a partition module and a voltage adjustment module.

[0020] The partition module is used to divide the display panel into multiple display areas;

[0021] The voltage regulating module is used to adjust the first supply voltage of the pixel units in the multiple display areas according to the LV characteristic curve, so that the display brightness of the OLEDs in the multiple display areas after aging is consistent.

[0022] According to another aspect of the present invention, there is provided an OLED display device, comprising the above-mentioned brightness compensation device, wherein an OLED array in the OLED display device comprises any one of micro OLED and AMOLED.

[0023] After being processed by the brightness compensation method of the OLED display device provided by the present invention, the brightness of the OLED in each area of ​​the display panel can be kept consistent. In one embodiment, the brightness is the brightness of the OLED in each area of ​​the display panel when it is not aged and is working normally; in another embodiment, the brightness is the brightness of the OLED in the area of ​​the display panel that is most aged (the overlapping area of ​​the screen) when it is working normally after aging. Both can achieve the above-mentioned effect and overcome the problem of uneven display brightness in the display device. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The above and other objects, features and advantages of the present invention will become more apparent through the following description of the embodiments of the present invention with reference to the accompanying drawings, in which:

[0025] Figure 1a A schematic diagram of a graphic movement trajectory according to the prior art is shown;

[0026] Figure 1b A schematic diagram showing the brightness of a display panel after a white image is displayed under a graphic moving track according to the prior art is shown;

[0027] Figure 2 A schematic structural diagram of an OLED display device provided in an embodiment of the present invention is shown;

[0028] Figure 3 A flow chart showing a brightness compensation method for an OLED display device according to an embodiment of the present invention is shown;

[0029] Figure 4 A schematic diagram of partitioning of a display panel according to an embodiment of the present invention is shown;

[0030] Figure 5a shows a schematic diagram of adjusting the supply voltage in the OLED brightness and voltage relationship curve according to the first embodiment of the present invention;

[0031] Figure 5b A schematic diagram showing the adjustment of the supply voltage in the OLED brightness and voltage relationship curve according to the second embodiment of the present invention is shown;

[0032] Figure 6A schematic diagram showing display brightness after the supply voltage of the display panel is adjusted according to an embodiment of the present invention is shown; DETAILED DESCRIPTION

[0033] Various embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. In each of the accompanying drawings, the same elements or modules are represented by the same or similar reference numerals. For the sake of clarity, the various parts in the accompanying drawings are not drawn to scale.

[0034] It should be understood that in the following description, a "circuit" may include a single or multiple combined hardware circuits, programmable circuits, state machine circuits, and / or elements capable of storing instructions executed by programmable circuits. When an element or circuit is said to be "connected to" another element or an element or circuit is said to be "connected between" two nodes, it may be directly coupled or connected to another element or there may be an intermediate element, and the connection between the elements may be physical, logical, or a combination thereof. Conversely, when an element is said to be "directly coupled to" or "directly connected to" another element, it means that there is no intermediate element between the two.

[0035] At the same time, certain words are used in this patent specification and claims to refer to specific components. It should be understood by those skilled in the art that hardware manufacturers may use different terms to refer to the same component. This patent specification and claims do not use differences in names as a way to distinguish components, but rather use differences in components' functions as the criteria for distinction.

[0036] In addition, it should be noted that, in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or equipment. In the absence of more restrictions, the elements defined by the statement "comprise one..." do not exclude the existence of other identical elements in the process, method, article or equipment including the elements.

[0037] Figure 2 A schematic structural diagram of an OLED display device provided according to an embodiment of the present invention is shown.

[0038] The OLED display device provided by the embodiment of the present invention includes a display panel 10, a driving display module and a brightness compensation device 20. The OLED array in the OLED display device includes any one of micro OLED and active-matrix Organic Light Emitting Diode (AMOLED).

[0039] The display panel 10 includes a plurality of gate lines G1-Gm, a plurality of data lines S1-Sn, and a plurality of pixel regions 4, wherein the plurality of pixel regions 4 include a plurality of pixel units 2, a plurality of organic light emitting diodes OLED, and a plurality of cathode electrodes (not shown in the figure) arranged corresponding to the plurality of pixel regions 4, wherein m and n are both positive integers. The driving display module includes a power supply module 40, which is connected to the display panel 10 and is used to provide a first power supply voltage VDD to the display panel 10. The pixel region 4 is connected to the gate line Gm, the data line Sn, and the first power supply voltage VDD.

[0040] In this embodiment, the pixel area 4 of the display panel 10 includes an organic light emitting diode OLED and a pixel unit 2 connected to a gate line Gm and a data line Sn to control the OLED. The cathode of the OLED is connected to the pixel unit 2, and the anode of the OLED is connected to the first power supply voltage VDD.

[0041] The pixel unit 2 controls the amount of current supplied to the OLED in response to the data signal supplied to the data line Sn when the scan signal is supplied to the gate line Gm, and the OLED generates light of a predetermined brightness in response to the current supplied by the pixel unit 2 .

[0042] The display driving module is used to provide a scanning signal and a data signal to the display panel in the display state to drive the display panel to display. The display driving module includes a gate driving circuit 32, which is used to provide a gate voltage to the display panel 10 in the display state; and a source driving circuit 31, which is used to provide a grayscale voltage to the display panel 10 in the display state.

[0043] It should be additionally explained that the circuit structure of the pixel unit 2 in the accompanying drawings is only an exemplary depiction and can be adjusted according to actual conditions. For example, when a touch function is added to the display device, a touch signal line can be added to the pixel unit and adjustments can be made according to the touch state or display state. This application does not impose any restrictions on this.

[0044] The OLED display device provided by the present invention further includes a brightness compensation device 20 for dividing the display panel into a plurality of display areas, and adjusting the first power supply voltage VDD of the pixel unit in the area accordingly according to the display area.

[0045] The brightness compensation device 20 includes a partition module 21 and a voltage adjustment module 22.

[0046] The partition module 21 is used to divide the display panel into a plurality of regions according to the display duration of the pixel units in the display panel when the picture track moves.

[0047] The voltage regulating module 22 is used to adjust the first supply voltage of the pixel units in the multiple display areas according to the LV characteristic curve, so that the display brightness of the OLEDs in the multiple display areas after aging is consistent.

[0048] Figure 3 A flow chart of a brightness compensation method for an OLED display device according to an embodiment of the present invention is shown. In this embodiment, the partition module 21 and the voltage adjustment module 22 in the brightness compensation device 20 together perform multiple steps of the brightness compensation method. For example, during the display process of the OLED display device, the brightness compensation device 20 performs steps S01 to S03 described in detail below, so that the brightness of the display panel presents multiple uneven display blocks for brightness compensation.

[0049] S01: Divide the display panel into a plurality of display areas.

[0050] The partition module 21 in the brightness compensation device 20 divides the display panel into multiple areas according to the display time of the OLED in the display panel when the picture track moves, which are a picture overlapping area, a transition area and a pixel moving area from long to short, wherein the transition area is located between the picture overlapping area and the pixel moving area; the picture overlapping area is the area where the OLED is always in the display state when the picture track moves; and the pixel moving area is the area in the display panel that expands outward due to the movement of the picture track.

[0051] Figure 4 A schematic diagram of a display panel partition according to an embodiment of the present invention is shown. Figure 4 In step S01, taking the normal display resolution of 1600x1200, 14 pixels are added in the vertical direction, 16 pixels are added in the horizontal direction, and the total resolution of the display panel is 1632x1228 as an example, wherein the added area is located at the outermost side of the display panel, corresponding to the pixel moving area, in the shape of a U.S. character. When displaying the picture, the image can move randomly or in a circular trajectory in this area, and the OLED has the shortest light-emitting time in this area.

[0052] When displaying a white screen, it is always in the display state. The area with the longest display time, namely the screen overlap area, is shrunk 14 pixels in the vertical direction and 16 pixels in the horizontal direction based on the normal display resolution. Therefore, the resolution size of the screen overlap area is (1600-32) x (1200-28). The area between the screen overlap area and the pixel shift area is the transition area, which is also in the shape of a U-shaped character.

[0053] The intervals between the outer edges and the inner edges of the transition area and the pixel moving area are the same, which are 14 pixels in the vertical direction and 16 pixels in the horizontal direction.

[0054] The above three areas are concentric, and are respectively the picture overlapping area, the transition area and the pixel moving area from the inside to the outside. During the display of the white picture, the OLED display time of each area decreases from the inside to the outside, so different degrees of aging will occur. Among them, the sum of the resolutions of the picture overlapping area and the transition area is the normal display resolution of the picture, and the sum of the three resolutions is the total resolution. In an optional embodiment, the overlapping area, the transition area and the pixel moving area can also be subdivided into multiple areas. The above partitioning method is not only applicable to OLED screens, but can also be applied to other screens such as LCD screens.

[0055] Step S02: testing pixel units in the plurality of display areas to obtain LV characteristic curves.

[0056] In this step, different LV characteristic curves need to be tested for the pixel units in the above-mentioned different display areas. The pixel units to be tested can be any pixels in different display areas, and the pixels can be represented as compensation pixels in this article. According to the embodiment of the present disclosure, the LV characteristic curve of the compensation pixel can be obtained by measuring and calculating the brightness value (corresponding to the vertical coordinate of the curve) of the compensation pixel under different first power supply voltages VDD (LV corresponding to the horizontal coordinate of the curve) through a brightness sensor.

[0057] The compensation pixels in the LV characteristic curve of the compensation pixels are not only divided into regions, but in an optional embodiment, the LV characteristic curve of the compensation pixels before and after displaying a white picture, that is, before and after aging, also needs to be obtained.

[0058] Step S03: adjusting the first supply voltages of the pixel units in the plurality of display areas according to the LV characteristic curve, so as to make the display brightness of the OLEDs in the plurality of display areas consistent.

[0059] In this step, the supply voltage (first supply voltage VDD) of the pixel units in different display areas is controlled to make the display brightness of the pixel units in each display area the same, thereby avoiding the display panel from presenting multiple uneven display blocks.

[0060] Figure 5a FIG. 4 is a schematic diagram showing the adjustment of the supply voltage in the OLED brightness and voltage relationship curve according to the first embodiment of the present invention.

[0061] In one embodiment, the first power supply voltage VDD is regulated according to the LV characteristic curves of the OLED before and after aging in each display area. Figure 5a In the figure, only a voltage control schematic diagram of an area is shown as an example, and the area can be any one of the above-mentioned areas, but in the control process, corresponding processing is performed on all display areas, and the brightness of the OLED in the multiple display areas when working normally before aging is used as a reference brightness value, and the first power supply voltage of the pixel unit in the multiple display areas is adjusted until the display brightness of the OLED in the multiple display areas after aging is consistent with the reference brightness value.

[0062] Specifically, in Figure 5a In the figure, point A represents the brightness value of the OLED after aging in any area under the first power supply voltage VDD during normal operation, and point B represents the brightness value of the OLED before aging in any area under the first power supply voltage VDD during normal operation. The brightness value of point B is used as a reference, and the first power supply voltage VDD supplied to the OLED in any area is increased until the brightness value of the OLED in any area after aging is consistent with the brightness value of point B, that is, the brightness value of the OLED after aging is compensated by increasing the first power supply voltage VDD (corresponding to the first power supply voltage VDD at point C). Because the working brightness values ​​of the OLEDs in the entire display panel before aging are consistent under the first power supply voltage VDD during normal operation, it can be achieved that the brightness of the OLEDs in the entire display panel is consistent after the voltage is adjusted in each area.

[0063] Figure 5b A schematic diagram of adjusting the supply voltage in the OLED brightness and voltage relationship curve according to the second embodiment of the present invention is shown.

[0064] In order to avoid further deterioration of the OLED in each display area, in another embodiment, the first power supply voltage VDD is regulated according to the LV characteristic curve of the OLED after aging in each display area, the brightness of the OLED in the overlapping area of ​​the picture when working normally after aging is used as a reference brightness value, and the first power supply voltage of the pixel unit in other areas is adjusted until the display brightness of the OLED in the other display area after aging is consistent with the reference brightness value.

[0065] Specifically, in Figure 5bIn the figure, the LV characteristic curves of the OLED after aging in each display area are included. According to the above display panel, from the inside to the outside, there are a picture overlap area, a transition area and a pixel movement area. In the process of displaying a white picture, the OLED display time of each area decreases from the inside to the outside. It can be obtained that the OLED in the picture overlap area has the longest display time and the most serious aging degree. Under the same first power supply voltage VDD, the brightness of the OLED in the picture overlap area is the lowest.

[0066] Point A1 represents the brightness value of the OLED after aging in the transition area under the first power supply voltage VDD during normal operation, point A2 represents the brightness value of the OLED after aging in the pixel moving area under the first power supply voltage VDD during normal operation, and point B represents the brightness value of the OLED after aging in the overlapping area of ​​the picture under the first power supply voltage VDD during normal operation. Taking the brightness value of point B as a reference, the first power supply voltage VDD supplied to the OLED in the transition area and the pixel moving area is reduced until the brightness value of the OLED in the transition area and the pixel moving area after aging is consistent with the brightness value of point B (corresponding to the first power supply voltage VDD at points C1 and C2, respectively).

[0067] Figure 6 A schematic diagram showing display brightness after the supply voltage of the display panel is adjusted according to an embodiment of the present invention is shown;

[0068] like Figure 6 As shown, after being processed by the brightness compensation method of the OLED display device in the embodiment of the present application, the brightness of the OLED in each area of ​​the display panel can be kept consistent. In one embodiment, referring to Figure 5a The brightness compensation method uses a positive adjustment method to enhance the brightness of the OLED in the aging area (overlap area and transition area) so that the brightness is consistent with the normal working brightness before aging; in another embodiment, referring to Figure 5b The brightness compensation method uses reverse adjustment to reduce the brightness of the OLED in the non-aging area (transition area and pixel movement area) to make it consistent with the brightness of the overlapping area after aging, and both can achieve consistent effects.

[0069] It should be noted that it will be understood by those skilled in the art that the words "during", "when" and "when ..." used in this article in connection with the operation of the circuit are not strict terms indicating an action that occurs immediately when the start-up action begins, but that there may be some small but reasonable one or more delays between it and the reaction action initiated by the start-up action, such as various transmission delays, etc. The words "approximately" or "substantially" used in this article mean that the element value has a parameter that is expected to be close to the declared value or position. However, as is well known in the art, there are always slight deviations that make it difficult for the value or position to be strictly the declared value. It has been properly determined in the art that a deviation of at least ten percent (10%) (for semiconductor doping concentrations, at least twenty percent (20%)) is a reasonable deviation from the accurate ideal target described. When used in conjunction with a signal state, the actual voltage value or logic state (e.g., "1" or "0") of the signal depends on whether positive logic or negative logic is used.

[0070] According to the embodiments of the present invention, as described above, these embodiments do not describe all the details in detail, nor do they limit the invention to specific embodiments. Obviously, many modifications and changes can be made based on the above description. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can make good use of the present invention and the modified use based on the present invention. The scope of protection of the present invention shall be based on the scope defined by the claims of the present invention and their equivalents.

Claims

1. A brightness compensation method for an OLED display device, comprising: Dividing the display panel into a plurality of display areas according to the duration of the OLED display in the display panel when the picture track moves; Testing pixel units in the plurality of display areas to obtain LV characteristic curves; The first supply voltages of the pixel units in the plurality of display areas are adjusted according to the LV characteristic curve, so that the display brightness of the OLEDs in the plurality of display areas after aging is consistent.

2. The brightness compensation method of an OLED display device according to claim 1, wherein the plurality of display areas are respectively a picture overlap area, a transition area and a pixel shift area from inside to outside, in, The transition area is located between the picture overlap area and the pixel shift area; The picture overlap area is the area where the OLED is always in display state when the picture track moves; The pixel moving area is an area in the display panel that is expanded for the movement of the picture track.

3. The brightness compensation method of the OLED display device according to claim 2, wherein: The centers of the picture overlap area, the transition area and the pixel shift area are consistent, the transition area and the pixel shift area are in a U-shape, and the distances between the outer edges and the inner edges of the two are the same.

4. The brightness compensation method of the OLED display device according to claim 2, wherein the LV characteristic curve comprises: LV characteristic curves of the OLEDs in the plurality of display areas after aging or LV characteristic curves of the OLEDs in the plurality of display areas before and after aging.

5. The brightness compensation method of the OLED display device according to claim 4, further comprising: The brightness of the OLEDs in the multiple display areas when they are working normally before aging is used as a reference brightness value, and the first supply voltage of the pixel units in the multiple display areas is adjusted until the display brightness of the OLEDs in the multiple display areas after aging is consistent with the reference brightness value.

6. The brightness compensation method of the OLED display device according to claim 4 further comprises taking the brightness of the OLED in the overlapping area of ​​the picture when it is working normally after aging as a reference brightness value, and adjusting the first supply voltage of the pixel unit in other display areas until the display brightness of the OLED in the other display areas after aging is consistent with the reference brightness value.

7. The brightness compensation method of an OLED display device according to claim 1, wherein: The step of testing the pixel units in the multiple display areas to obtain the LV characteristic curve includes: measuring and calculating the brightness value of the pixel under different first supply voltages for any pixel unit in the multiple display areas.

8. A brightness compensation device, comprising: Partitioning module and voltage regulation module, The partition module is used to divide the display panel into multiple display areas according to the OLED display duration in the display panel when the picture track moves; The voltage regulating module is used to adjust the first supply voltage of the pixel units in the multiple display areas according to the LV characteristic curve, so that the display brightness of the OLEDs in the multiple display areas after aging is consistent.

9. An OLED display device, comprising the brightness compensation device according to claim 8, wherein: The OLED array in the OLED display device includes any one of micro OLED and AMOLED.

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