Organic light emitting display device and driving method thereof

Abstract

The present application discloses an organic light-emitting display device and a driving method thereof, which relates to the field of display technology. The organic light-emitting display device includes an organic light-emitting display panel, an electrochromic device, a control circuit, a comparison module, a first driving module and a second driving module. The comparison module is connected to the control circuit and is used to compare the grayscale value of each pixel with the preset grayscale value. When the grayscale value is less than the preset grayscale value, the first driving module compensates the grayscale value according to a compensation formula, and the second driving module reduces the output voltage to the color-changing area according to an adjustment coefficient, thereby reducing the light output brightness of the color-changing area to the pixel area. Through the above design, while the dark details of the dark area in the display screen are perfectly presented, the problem of reduced contrast caused by increasing the brightness of the entire dark area can also be avoided.

Description

Technical Field

[0001] The present application relates to the field of display technology, and in particular to an organic light-emitting display device and a driving method thereof. Background Art

[0002] With the rapid development of the optoelectronic display industry and the replacement of screens, more and more products are using organic light-emitting diode (OLED) displays in addition to liquid crystal displays (LCD). Due to its light-emitting principle, OLED displays do not require backlights, have good flexibility, and have bright colors. They are also called "dream displays" and are loved by a large number of users.

[0003] However, when displaying low-grayscale dark images, OLED screens often cannot fully present the dark details perfectly, resulting in poor display of dark details. Summary of the invention

[0004] The purpose of the present application is to provide an organic light emitting display device and a driving method thereof, which can well present the dark details in the display screen.

[0005] The present application discloses an organic light-emitting display device, including an organic light-emitting display panel, an electrochromic device, a control circuit, a comparison module, a first driving module and a second driving module. A plurality of pixel areas are arranged in an array on the organic light-emitting display panel. The electrochromic device is arranged on the light-emitting side of the organic light-emitting display panel. The electrochromic device is divided into a plurality of color-changing areas. The color-changing areas correspond to at least one pixel area in the organic light-emitting display panel, and the color-changing areas are used to adjust the light-emitting brightness of the corresponding pixel area. The control circuit is used to receive display data and generate a grayscale value corresponding to the pixel area. The comparison module is connected to the control circuit and is used to compare the grayscale value with a preset grayscale value.

[0006] The first driving module is connected to the organic light-emitting display panel and the comparison module. When the grayscale value is less than the preset grayscale value, the first driving module compensates for the grayscale value according to a compensation formula and outputs the compensated grayscale value to the corresponding pixel area. The second driving module is connected to the electrochromic device and the comparison module. When the grayscale value is less than the preset grayscale value, the second driving module reduces the output voltage to the color-changing area according to an adjustment coefficient, thereby reducing the light output brightness of the color-changing area to the pixel area. The preset grayscale value is a critical value when the dark area in the display screen of the organic light-emitting display panel displays abnormally.

[0007] Optionally, the electrochromic device includes a first base layer, a first electrode layer, an ion storage layer, an ion conduction layer, an electrochromic layer, a second electrode layer and a second base layer stacked in sequence, the first base layer and the second base layer are composed of a transparent insulating material, the first electrode layer and the second electrode layer are composed of a transparent conductive material, and the electrochromic layer is composed of a nanowire material; the electrochromic layer includes a plurality of nanowire material blocks, and an array of the plurality of nanowire material blocks is distributed on the first base layer and corresponds one-to-one to the color changing areas; the second driving module is respectively connected to the first electrode layer and the second electrode layer, controls the voltage of the first electrode layer and the second electrode layer, so as to control the transparency of each of the nanowire material blocks.

[0008] Optionally, the nanowire material includes at least one of tungsten oxide, vanadium oxide, metallic silver or iridium oxide.

[0009] Optionally, the first electrode layer is connected to the positive electrode of the second driving module, the second electrode layer is connected to the negative electrode of the driving module, and the driving module only controls the voltage of the first electrode layer.

[0010] Optionally, the organic light-emitting display panel includes a substrate, a cathode, an electron injection layer, an electron transport layer, a light-emitting layer, a hole transport layer, a hole injection layer, an anode and an encapsulation layer stacked in sequence, and the electrochromic device is arranged between the anode and the encapsulation layer.

[0011] Optionally, the compensation formula is: when the grayscale value is less than the preset grayscale value, the grayscale value is compensated to the sum of the preset grayscale value and 10-20 grayscale; the adjustment coefficient is: when the grayscale value is less than the preset grayscale value, the grayscale value corresponding to the color change area is adjusted to 30-40 grayscale.

[0012] Optionally, the control circuit includes an overdrive control unit, a Gamma module and an algorithm controller, the overdrive control unit is used to receive and store display data of the picture, the Gamma module is connected to the overdrive control unit, and is used to convert the display data into grayscale values; the algorithm controller is connected to the Gamma module and the overdrive control unit, and is used to analyze the display data to obtain the range of the dark picture area, and extract the grayscale value corresponding to each pixel area in the dark picture area; the comparison module is connected to the algorithm controller, and compares the grayscale value corresponding to each pixel area in the dark picture area with the preset grayscale value; the first drive module includes a data drive circuit and a gate drive circuit, one end of the data drive circuit and the gate drive circuit are respectively connected to the comparison module, and the other end is respectively connected to the organic light-emitting display panel.

[0013] The present application also discloses a driving method of an organic light-emitting display device, which is used to drive the organic light-emitting display device as described above, comprising the steps of:

[0014] Receive display data of the next frame;

[0015] Calculating the grayscale value corresponding to the pixel area according to the display data;

[0016] Comparing the grayscale value corresponding to the pixel area with the preset grayscale value; and

[0017] When the grayscale value is less than the preset grayscale value, the grayscale value is compensated according to the compensation formula, and the compensated grayscale value is output to the corresponding pixel area. At the same time, the light output brightness of the corresponding chromatic area in the electrochromic device located on the light output side of the organic light-emitting display panel is reduced; when the grayscale value is greater than or equal to the preset grayscale value, the size of the corresponding grayscale value is not changed, and the light output brightness of the corresponding chromatic area in the electrochromic device is not changed.

[0018] Optionally, the step of calculating the grayscale value corresponding to the pixel area according to the display data includes:

[0019] storing the display data in an overdrive control unit;

[0020] Converting the display data into grayscale values ​​using a gamma module; and

[0021] The display data is analyzed by an algorithm controller to obtain the dark image area range, and the grayscale value corresponding to each pixel area in the dark image area range is extracted.

[0022] Optionally, the step of comparing the grayscale value corresponding to the pixel area with the preset grayscale value includes:

[0023] Testing the preset grayscale value; and

[0024] Comparing the grayscale value corresponding to the pixel area in the dark image area with the preset grayscale value;

[0025] Wherein, the step of testing the preset grayscale value includes:

[0026] Selecting an abnormal picture, and reading the lowest grayscale value in the abnormal picture;

[0027] Selecting a normal picture, and gradually reducing the grayscale value in the normal picture until a first preset picture is obtained;

[0028] Reading the lowest grayscale value in the first preset image;

[0029] Comparing the lowest grayscale value in the abnormal image with the lowest grayscale value in the first preset image, and selecting the larger grayscale value as the critical grayscale value; and

[0030] Repeat the above steps to obtain a plurality of critical grayscale values, and calculate an average value of the plurality of critical grayscale values ​​as the preset grayscale value.

[0031] Compared with the solution of improving the poor display effect of dark details by improving the display brightness of OLED and highlighting the dark details, the present application determines the darker dark area of ​​the subsequent display screen through the control circuit and the comparison module, and then compensates the display brightness of the dark area through the first driving circuit. At the same time, an electrochromic device and a corresponding second driving module are added to the organic light-emitting display device; because the second driving module can accurately control the light output brightness of the electrochromic device, the dark details of the dark area in the display screen are perfectly presented, and the problem of reduced contrast caused by increasing the brightness of the entire dark area can also be avoided. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The included drawings are used to provide a further understanding of the embodiments of the present application, which constitute a part of the specification, are used to illustrate the implementation methods of the present application, and together with the text description, explain the principles of the present application. 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 creative work. In the drawings:

[0033] Figure 1 is a cross-sectional schematic diagram of an organic light-emitting display device provided in an embodiment of the present application;

[0034] Figure 2 is a cross-sectional schematic diagram of an electrochromic device provided in an embodiment of the present application;

[0035] Figure 3 is a partial schematic diagram of an organic light emitting display device provided in an embodiment of the present application;

[0036] Figure 4 is a flow chart of a driving method of an organic light emitting display device provided in an embodiment of the present application;

[0037] Figure 5 is a flow chart of another driving method of an organic light emitting display device provided in an embodiment of the present application;

[0038] Figure 6 This is a flow chart of another driving method of an organic light emitting display device provided in an embodiment of the present application.

[0039] Among them, 10, organic light-emitting display device; 20, printed circuit board; 21, system interface circuit; 22, command decoder; 23, power supply circuit; 30, timing control chip; 100, organic light-emitting display panel; 110, substrate; 120, cathode; 130, electron injection layer; 140, electron transport layer; 150, light-emitting layer; 160, hole transport layer; 170, hole injection layer; 180, anode; 190, encapsulation layer; 200, electrochromic device; 200a, color change area; 210, first base layer; 220, first An electrode layer; 230, an ion storage layer; 240, an ion conduction layer; 250, an electrochromic layer; 251, a nanowire material block; 260, a second electrode layer; 270, a second base layer; 300, a control circuit; 310, an overdrive control unit; 320, an algorithm controller; 330, a gamma module; 331, a grayscale generator; 332, a gamma correction module; 400, a comparison module; 500, a first drive module; 510, a data drive circuit; 520, a gate drive circuit; 600, a second drive module. DETAILED DESCRIPTION

[0040] It should be understood that the terms used herein, the specific structures and functional details disclosed are only for describing specific embodiments and are representative, but the present application can be implemented in many alternative forms and should not be construed as being limited to only the embodiments described herein.

[0041] In addition, unless otherwise clearly specified or limited, "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be internally connected between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0042] At present, when a part of the OLED screen is a low-grayscale dark state picture, the details of the picture cannot be perfectly presented, but it is displayed in a completely black state (i.e., zero grayscale state) or a grayscale lower than the original picture should be displayed, resulting in a very poor user experience; the reasons for the poor display effect of the dark details of OLED (also known as "dead black") are, firstly, because the brightness of OLED and the data voltage (i.e., data value) of the data line (Source line) are not linearly related, when the data value is small, the impact on the display brightness of OLED is not obvious; secondly, when OLED uses PWM dimming technology to adjust the brightness of the picture (the so-called PWM dimming technology, in simple terms, is to control the brightness of each OLED lamp by controlling the duty cycle in a display cycle. The brighter the brightness, the larger the duty cycle, and vice versa), the low-grayscale picture display brightness is low, and when PWM dimming technology is used for low grayscale and low brightness, its duty cycle will be smaller and more precise, and the adjustment accuracy of PWM technology cannot fully achieve the dimming effect. Combining the above two reasons, when OLED displays a dark image, it may directly display black or a grayscale lower than the original image should display.

[0043] Based on this, an embodiment of the present application provides an organic light-emitting display device and a driving method thereof to improve the above-mentioned technical problems. The present application is described in detail below with reference to the accompanying drawings and optional embodiments.

[0044] like Figure 1 As shown, an embodiment of the present application provides an organic light-emitting display device 10, including an organic light-emitting display panel 100, an electrochromic device 200, a control circuit 300, a comparison module 400, a first driving module 500 and a second driving module 600, wherein a plurality of pixel areas are arrayed on the organic light-emitting display panel 100, and each pixel area corresponds to a light-emitting unit; the electrochromic device 200 is arranged on the light-emitting side of the organic light-emitting display panel 100, and the electrochromic device 200 is divided into a plurality of color-changing areas 200a, wherein the color-changing areas 200a correspond to at least one pixel area in the organic light-emitting display panel 100, and the color-changing areas 200a are used to adjust the light-emitting brightness corresponding to the pixel area; wherein the color-changing areas 200a can adjust the final light-emitting brightness of the organic light-emitting display device 10 by adjusting their own transparency, adjusting their own brightness, etc.

[0045] The control circuit 300 is used to receive display data and generate a grayscale value corresponding to the pixel area; the comparison module 400 is connected to the control circuit 300 and is used to compare the grayscale value with a preset grayscale value; the first driving module 500 is connected to the organic light-emitting display panel 100 and the comparison module 400. When the grayscale value is less than the preset grayscale value, the first driving module 500 compensates the grayscale value according to a compensation formula and outputs the compensated grayscale value to the corresponding pixel area; the second driving module 600 is connected to the electrochromic device 200 and the comparison module 400. When the grayscale value is less than the preset grayscale value, the second driving module 600 reduces the output voltage to the color changing area 200a according to the adjustment coefficient, thereby reducing the light output brightness of the color changing area 200a to the pixel area; wherein the preset grayscale value is a critical value when the dark area in the display screen of the organic light-emitting display panel 100 displays abnormally.

[0046] At present, in order to solve the problem that OLED has poor display effect of dark details when displaying low-grayscale dark images, the display brightness of OLED can be increased to highlight the dark details; simply increasing the display brightness of OLED can show the details of dark areas, but it reduces the contrast and cannot reflect the original high contrast advantage of OLED, while increasing power consumption; in addition, due to the characteristics of OLED itself, its luminous brightness limit is not very high, so simply increasing the display brightness of OLED cannot effectively improve the problem of poor display effect of dark details.

[0047] The present application determines the darker dark area in the subsequent display image through the control circuit 300 and the comparison module 400, and then compensates the display brightness of the dark area through the first driving circuit. At the same time, an electrochromic device 200 and a corresponding second driving module 600 are added to the organic light-emitting display device 10; because the second driving module 600 can accurately control the light output brightness of the electrochromic device 200, the dark details of the dark area in the display image can be perfectly presented, and the problem of reduced contrast caused by increasing the brightness of the entire dark area can also be avoided.

[0048] Specifically, the compensation formula is: when the grayscale value is less than the preset grayscale value, the grayscale value is compensated to the sum of the preset grayscale value and 10-20 grayscale; the use of this compensation formula will not increase the luminous brightness of the LED too much, thereby reducing energy consumption. The adjustment coefficient is: when the grayscale value is less than the preset grayscale value, the grayscale value corresponding to the color change area 200a is adjusted to 30-40 grayscale; since the human eye can clearly see the picture with a grayscale brightness of 30-40, a grayscale lower than 30 will cause the human eye to be unable to see the specific structure, so the use of this adjustment coefficient can ensure that the user can see the dark details of each part of the display picture clearly, and will not affect the contrast with other display areas.

[0049] The organic light emitting display device 10 includes a printed circuit board 20, and the control circuit 300, the comparison module 400, the first driving module 500, and the second driving module 600 are all arranged on the printed circuit board 20. Specifically, the printed circuit board 20 is provided with a system interface circuit 21, and the system interface circuit 21 is used to receive data a and command b, and the system interface circuit 21 identifies the command b through a command decoder 22; the printed circuit board 20 is also provided with a power circuit 23 and a timing controller chip 30 (Timing controller, TCON), and the power circuit 23 is used to connect to a power supply c, and the timing controller chip 30 serves as the main control of the organic light emitting display device 10.

[0050] The control circuit 300 includes an over-driving control unit 310 (OD), an algorithm controller 320 and a Gamma module 330. The over-driving control unit 310 is also called an image RAM, which is used to receive and store display data of the picture and is a part of the timing control chip 30. Of course, the timing control chip 30 can also be used as a part of the control circuit 300. The Gamma module 330 is connected to the over-driving control unit 310 and is used to convert the display data into grayscale values. The Gamma module 330 specifically includes a grayscale generator 331 and a Gamma correction module 332. The grayscale generator 331 is connected to the over-driving control unit 310 and is used to convert the display data into corresponding grayscale values. The Gamma correction module 332 is connected to the grayscale generator 331 to correct the grayscale values. The algorithm controller 320 is connected to the Gamma module 330 and the overdrive control unit 310, and specifically to the timing control chip 30, to achieve mutual connectivity, so as to analyze the display data to obtain the range of the dark picture area, and extract the grayscale value corresponding to each pixel area in the dark picture area, which can also be understood as extracting the grayscale values ​​of all pixel areas corresponding to the dark picture area in a frame of the picture converted by the Gamma module 330.

[0051] The comparison module 400 is connected to the algorithm controller 320 to compare the grayscale value corresponding to each pixel area in the dark image area with the preset grayscale value; the first driving module 500 includes a data driving circuit 510 and a gate driving circuit 520, one end of the data driving circuit 510 and the other end of the gate driving circuit 520 are respectively connected to the comparison module 400, and the other end is respectively connected to the organic light emitting display panel 100. The comparison module 400 can be used as a part of the algorithm controller 320.

[0052] like Figure 2 As shown, the electrochromic device 200 adopts an electrochromic nanowire assembly, which is a stacked or arrayed structure, specifically including a first base layer 210, a first electrode layer 220, an ion storage layer 230, an ion conduction layer 240, an electrochromic layer 250, a second electrode layer 260 and a second base layer 270 stacked in sequence.

[0053] The first base layer 210 and the second base layer 270 are made of transparent insulating materials, specifically glass materials. The first electrode layer 220 and the second electrode layer 260 are made of transparent conductive materials, such as indium tin oxide (ITO), aluminum zinc oxide (AZO), indium zinc oxide (IZO), zinc oxide (ZnO) or germanium zinc oxide (GZO). The ion storage layer 230 is made of a film such as a nano nickel oxide film or a nano nickel iron oxide film. The ion conduction layer 240 is used to conduct ions, and a general conduction film can be selected.

[0054] The electrochromic layer 250 is composed of nanowire material, and the nanowire material is formed of one of the materials with electrochromic properties such as tungsten oxide, vanadium oxide, metallic silver or iridium oxide, or a mixture of two or more of them. Specifically, the nanowire material array can be prepared on the stacked first base layer 210, the first electrode layer 220, the ion storage layer 230 and the ion conduction layer 240 by a suspension method, a deposition method, a synthesis method or the like to form the electrochromic layer 250, and then the second electrode layer 260 is formed on the electrochromic layer 250, and finally the second base layer 270 is covered on the second electrode layer 260 to form a layer of array nanowire assembly film.

[0055] The characteristic of the electrochromic device 200 is that a certain voltage can be applied to the device so that it can display different images from its original transparent state. In the embodiment of the present application, a transparent film with an array of nanowire assemblies is covered on the upper layer of the LED of the OLED display screen product. When the dark part of the picture needs to show the detail effect, the brightness of the LED light displayed in this part is first increased, and then the characteristics of the nanowire assembly are used to shield the part. Although the LED light cannot present the detail effect well in the dark state, the nanowires can control the brightness of the light passing through after the brightness is increased in the embodiment of the present application, thereby achieving the purpose of showing the dark details of the OLED screen.

[0056] In the embodiment of the present application, the nanowires in the electrochromic layer 250 are arranged in an array. Specifically, the electrochromic layer 250 includes a plurality of nanowire material blocks 251, and the plurality of nanowire material blocks 251 are arrayed on the first base layer 210 and correspond one-to-one to the color changing areas 200a.

[0057] When designing the size of the nanowire array, the actual situation and needs are taken into consideration. The entire electrochromic layer 250 can be divided into thousands of display blocks (nanowire material blocks 251) according to the display area size; it can also be divided at the pixel level with one nanowire material block 251 corresponding to every few pixel areas; or even more so, it can be divided at the sub-pixel level, that is, one nanowire material block 251 corresponds to each pixel area.

[0058] Among them, the division of nanowires in the electrochromic layer 250 is adaptively selected according to different OLED products. For low-, medium- and high-end OLED products, nanowires with different array sizes are controlled, and the accuracy of display effects controlled by nanowires with different array sizes will also increase step by step.

[0059] The second driving module 600 is connected to the first electrode layer 220 and the second electrode layer 260 , respectively, and controls the voltage of the first electrode layer 220 and the second electrode layer 260 to control the transparency of each of the nanowire material blocks 251 .

[0060] Furthermore, the first electrode layer 220 is connected to the positive electrode of the second driving module 600, and the second electrode layer 260 is connected to the negative electrode of the driving module, and the driving module only controls the voltage of the first electrode layer 220. The second driving module 600 only needs to adjust the voltage of the first electrode layer 220 to control the transparency of the electrochromic device 200, and does not need to adjust the two electrodes at the same time, which is conducive to simplifying the circuit design; of course, the driving module can also control the voltages of the first electrode layer 220 and the second electrode layer 260 at the same time.

[0061] The embodiment of the present application can also design the electrochromic device 200 as an anti-peeping film. When the electrochromic device 200 is designed as an anti-peeping film, since the anti-peeping film adopts the principle of ultra-fine blinds, the transmission angle of light is adjusted to control the visible angle. When in use, it is only necessary to determine which display areas will display dark images and increase the display brightness of this part. At the same time, the ultra-fine blinds structure of this area is controlled to adjust the tilt angle to adjust the dark image to an appropriate brightness.

[0062] In the embodiment of the present application, the electrochromic device 200 may also be designed as a liquid crystal layer. When the electrochromic device 200 is designed as a liquid crystal layer, brightness adjustment may be achieved by adjusting the deflection angle of the liquid crystal in the liquid crystal layer.

[0063] However, compared to the scheme of designing the electrochromic device 200 as an anti-peeping film or a liquid crystal layer, the scheme of designing the electrochromic device 200 as a nanowire assembly will not cause the problem of the overall brightness of the screen display being reduced due to the presence of opaque parts in the ultra-fine blinds, which will reduce the light transmittance, nor will it cause the liquid crystal to reduce the light transmittance, affecting the display effect of the normal screen. Because the nanowire assembly has a theoretical maximum light transmittance of 97.3% through the combination of different metal oxides, it will not be affected by the nanowires when displaying non-dark images. In addition, since one of the major features of OLED screens is their high flexibility, most of the common folding screen products on the market currently use OLED screens, and the nanowire assembly itself is made of nano-scale materials and has good flexibility, so using the nanowire assembly in OLED screen products will not affect the flexibility of the OLED screen.

[0064] Therefore, the embodiment of the present application forms an electrochromic device 200 by using an electrochromic nanowire assembly. When the OLED needs to display a dark picture, the display brightness of this part of the picture is first increased, and then the electrochromic performance of the nanowire assembly is used to control the light that finally passes through its own OLED, thereby achieving the effect of accurately controlling the output of the dark picture. The device has the characteristics of low energy consumption, controllable display area, and good flexibility, which greatly improves the display effect of the OLED display screen without affecting the high contrast characteristics of the OLED product, making the OLED product more competitive.

[0065] like Figure 3As shown, the organic light emitting display panel 100 includes a substrate 110, a cathode 120, an electron injection layer 130, an electron transport layer 140, a light emitting layer 150, a hole transport layer 160, a hole injection layer 170, an anode 180 and an encapsulation layer 190 which are stacked in sequence, and the electrochromic device 200 is arranged between the anode 180 and the encapsulation layer 190. Compared with the solution of arranging the electrochromic device 200 outside the encapsulation layer 190, arranging the electrochromic device 200 between the anode 180 and the encapsulation layer 190 can prevent the electrochromic device 200 from being scratched, and since the electrochromic device 200 is directly sealed with the encapsulation layer at the end, there is no need to use additional glue to fix the electrochromic device 200. Of course, the embodiment of the present application can also directly arrange the electrochromic device 200 outside the encapsulation layer 190.

[0066] Correspondingly, such as Figure 4 As shown, the present application also discloses a driving method of an organic light-emitting display device, which is used to drive the above-mentioned organic light-emitting display device. The driving method specifically includes the steps of:

[0067] S1: Receive display data of the next frame;

[0068] S2: Calculating the grayscale value corresponding to the pixel area according to the display data;

[0069] S3: comparing the grayscale value corresponding to the pixel area with a preset grayscale value;

[0070] S4: When the grayscale value is less than the preset grayscale value, the grayscale value is compensated according to the compensation formula, and the compensated grayscale value is output to the corresponding pixel area. At the same time, the light output brightness of the corresponding electrochromic area in the electrochromic device located on the light output side of the organic light-emitting display panel is reduced; when the grayscale value is greater than or equal to the preset grayscale value, the size of the corresponding grayscale value is not changed, and the light output brightness of the corresponding electrochromic area in the electrochromic device is not changed.

[0071] like Figure 5 As shown, in step S2, it includes:

[0072] S21: storing the display data in an overdrive control unit;

[0073] S22: using a gamma module to convert the display data into grayscale values;

[0074] S23: Analyzing the display data through an algorithm controller to obtain a dark image area range, and extracting a grayscale value corresponding to each pixel area in the dark image area range.

[0075] like Figure 6As shown, in step S3, the following steps are specifically included:

[0076] S31: Testing the preset grayscale value;

[0077] S32: Compare the grayscale value corresponding to the pixel area in the dark image area with the preset grayscale value.

[0078] The embodiment of the present application further provides a method for testing the preset grayscale value. Specifically, in step S31, the method includes:

[0079] S311: selecting an abnormal picture, and reading the lowest grayscale value in the abnormal picture;

[0080] S312: selecting a normal picture, and gradually reducing the grayscale value in the normal picture until a first preset picture is obtained;

[0081] S313: reading the lowest grayscale value in the first preset image;

[0082] S314: comparing the lowest grayscale value in the abnormal image with the lowest grayscale value in the first preset image, and selecting the larger grayscale value as the critical grayscale value;

[0083] S315: Repeat the above steps to obtain a plurality of critical grayscale values, and calculate an average value of the plurality of critical grayscale values ​​as the preset grayscale value.

[0084] In the above disclosed method for testing the preset grayscale value, first, by finding a product of the same type as the organic light-emitting display device provided by the present application before improvement, or directly a test product of the organic light-emitting display device provided by the present application before improvement, find a picture of the OLED product showing poor dark details, i.e., the abnormal picture in S311, and then take a picture with a CCD camera to read and find the lowest grayscale value (G1) in the picture. Then, select a picture of the above OLED product showing normal display, i.e., the normal picture in S312; then, gradually reduce the input data voltage to reduce its grayscale value, and when it is found that the dark part is poorly displayed, the picture is judged to be the first preset picture in S312, and at the same time, take a picture with a CCD camera again to read its lowest grayscale value (G2). Then, compare the values ​​of G1 and G2, and select the larger grayscale value as the critical grayscale that can be used to determine that the dark part is poorly displayed, i.e., the critical grayscale value in S314. Finally, the above steps S311 to S314 are repeated multiple times, and the average value is finally calculated through multiple experimental data to determine a critical grayscale value (Gx), that is, the preset grayscale value in step S315, to improve the test accuracy.

[0085] Alternatively, in step S2, the dark area can be extracted by another method, which is as follows: after the display panel is powered on, the picture data to be displayed in the next frame will be stored in the over-driving control unit (OD) inside the timing controller (TCON), and the algorithm controller is used to read the data to be displayed for analysis. When the data voltage difference is large (for example, the grayscale voltages of the first to third rows of the data lines are read as 10, 11, and 12, respectively, that is, the display is a low gray state and its values ​​are all less than the critical grayscale Gx), and the data is analyzed to be transmitted down for several rows (for example, the data with a grayscale voltage of 10 is transmitted from the first row to the tenth row), it means that the display range of this dark area is the first to third rows of the data lines and the first to tenth rows of the scan lines. At this time, the result obtained by the algorithm controller is the dark picture to be displayed.

[0086] Further, in step S4, the analysis results are fed back to the second driving module that controls the voltage of the electrochromic device; at the same time, TCON transmits these data to the data driving circuit (Source driver) that controls the screen display. For example: when the source driver controls the data output, the screen that should have been displayed as 10 grayscales is actually output as 20 grayscales (this is just an example, 10 grayscales indicate that the OLED cannot accurately output grayscale data, and 20 grayscales are grayscale data that can be accurately output). At this time, the second driving module controls the color change area (that is, the nanowires) in this area to output bias voltage, so that the transparency of these nanowires is reduced, and the 10 grayscale display effect is achieved by controlling the occlusion of the nanowires, thereby presenting this part of the screen more accurately and solving the problem of poor display of dark details on the OLED screen.

[0087] For the compensation of the grayscale of the dark picture area by the data driving circuit, and the regulation of the nanowires by the second driving module, please refer to the description in the above embodiment: when the grayscale value is less than the preset grayscale value, the grayscale value is compensated to the sum of the preset grayscale value and 10-20 grayscale; when the grayscale value is less than the preset grayscale value, the grayscale value corresponding to the color change area is adjusted to 30-40 grayscale.

[0088] It should be noted that the limitations on the various steps involved in this solution are not considered to limit the order of the steps without affecting the implementation of the specific solution. The steps written in front can be executed first, or later, or even simultaneously. The solutions of different implementation embodiments can be combined and applied without conflict. As long as this solution can be implemented, it should be regarded as belonging to the scope of protection of this application.

[0089] The above content is a further detailed description of the present application in combination with specific optional implementation methods, and it cannot be determined that the specific implementation of the present application is limited to these descriptions. For ordinary technicians in the technical field to which the present application belongs, several simple deductions or substitutions can be made without departing from the concept of the present application, which should be deemed to fall within the scope of protection of the present application.

Claims

1. An organic light emitting display device, characterized in that: include: An organic light emitting display panel, wherein a plurality of pixel areas are arranged in an array on the organic light emitting display panel; An electrochromic device, arranged on the light-emitting side of the organic light-emitting display panel, the electrochromic device is divided into a plurality of color-changing regions, the color-changing regions correspond to at least one pixel region in the organic light-emitting display panel, and the color-changing regions are used to adjust the light-emitting brightness corresponding to the pixel region; A control circuit, used for receiving display data and generating a grayscale value corresponding to the pixel area; A comparison module, connected to the control circuit, and used for comparing the grayscale value with a preset grayscale value; A first driving module connected to the organic light emitting display panel and the comparison module, when the grayscale value is less than a preset grayscale value, the first driving module compensates the grayscale value according to a compensation formula, and outputs the compensated grayscale value to the corresponding pixel area; as well as A second driving module is connected to the electrochromic device and the comparison module, and when the grayscale value is less than a preset grayscale value, the second driving module reduces the output voltage to the color changing area according to the adjustment coefficient, thereby reducing the light output brightness of the color changing area to the pixel area; The preset grayscale value is a critical value when a dark area in a display image of the organic light emitting display panel displays an abnormality.

2. The organic light emitting display device according to claim 1, wherein: The electrochromic device comprises a first base layer, a first electrode layer, an ion storage layer, an ion conduction layer, an electrochromic layer, a second electrode layer and a second base layer which are stacked in sequence, wherein the first base layer and the second base layer are made of a transparent insulating material, the first electrode layer and the second electrode layer are made of a transparent conductive material, and the electrochromic layer is made of a nanowire material; The electrochromic layer includes a plurality of nanowire material blocks, and an array of the plurality of nanowire material blocks is distributed on the first base layer and corresponds one-to-one to the color changing areas; the second driving module is respectively connected to the first electrode layer and the second electrode layer to control the voltage of the first electrode layer and the second electrode layer to control the transparency of each of the nanowire material blocks.

3. The organic light emitting display device according to claim 2, wherein: The nanowire material includes at least one of tungsten oxide, vanadium oxide, metallic silver or iridium oxide.

4. The organic light emitting display device according to claim 2, wherein: The first electrode layer is connected to the positive electrode of the second driving module, the second electrode layer is connected to the negative electrode of the driving module, and the driving module only controls the voltage of the first electrode layer.

5. The organic light emitting display device according to claim 1, wherein: The organic light-emitting display panel includes a substrate, a cathode, an electron injection layer, an electron transport layer, a light-emitting layer, a hole transport layer, a hole injection layer, an anode and an encapsulation layer which are stacked in sequence, and the electrochromic device is arranged between the anode and the encapsulation layer.

6. The organic light emitting display device according to claim 1, wherein: The compensation formula is: when the grayscale value is less than the preset grayscale value, the grayscale value is compensated to the sum of the preset grayscale value and 10-20 grayscales; The adjustment coefficient is: when the grayscale value is less than the preset grayscale value, the grayscale value corresponding to the color change area is adjusted to 30-40 grayscale.

7. The organic light emitting display device according to claim 1, wherein: The control circuit comprises: An overdrive control unit, used for receiving and storing display data of the picture; A gamma module connected to the overdrive control unit, and configured to convert the display data into grayscale values; and An algorithm controller, connected to the Gamma module and the overdrive control unit, for analyzing the display data to obtain a dark image area range, and extracting a grayscale value corresponding to each pixel area in the dark image area range; The comparison module is connected to the algorithm controller and compares the grayscale value corresponding to each pixel area in the dark image area with the preset grayscale value; The first driving module includes a data driving circuit and a gate driving circuit. One end of the data driving circuit and the gate driving circuit are respectively connected to the comparison module, and the other end of the data driving circuit and the gate driving circuit are respectively connected to the organic light emitting display panel.

8. A method for driving an organic light emitting display device, for driving the organic light emitting display device according to any one of claims 1 to 7, characterized in that: Includes steps: Receive display data of the next frame; Calculating the grayscale value corresponding to the pixel area according to the display data; Comparing the grayscale value corresponding to the pixel area with the preset grayscale value; as well as When the grayscale value is less than the preset grayscale value, the grayscale value is compensated according to the compensation formula, and the compensated grayscale value is output to the corresponding pixel area. At the same time, the light output brightness of the corresponding chromatic area in the electrochromic device located on the light output side of the organic light-emitting display panel is reduced; when the grayscale value is greater than or equal to the preset grayscale value, the size of the corresponding grayscale value is not changed, and the light output brightness of the corresponding chromatic area in the electrochromic device is not changed.

9. The driving method of the organic light emitting display device according to claim 8, wherein: The step of calculating the grayscale value corresponding to the pixel area according to the display data includes: storing the display data in an overdrive control unit; Converting the display data into grayscale values ​​using a gamma module; and The display data is analyzed by an algorithm controller to obtain the dark image area range, and the grayscale value corresponding to each pixel area in the dark image area range is extracted.

10. The driving method of the organic light emitting display device according to claim 9, wherein: The step of comparing the grayscale value corresponding to the pixel area with the preset grayscale value includes: Testing the preset grayscale value; and Comparing the grayscale value corresponding to the pixel area in the dark image area with the preset grayscale value; Wherein, the step of testing the preset grayscale value includes: Selecting an abnormal picture, and reading the lowest grayscale value in the abnormal picture; Selecting a normal picture, and gradually reducing the grayscale value in the normal picture until a first preset picture is obtained; Reading the lowest grayscale value in the first preset image; Comparing the lowest grayscale value in the abnormal image with the lowest grayscale value in the first preset image, and selecting the larger grayscale value as the critical grayscale value; and Repeat the above steps to obtain a plurality of critical grayscale values, and calculate an average value of the plurality of critical grayscale values ​​as the preset grayscale value.

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