Display device and image display method

Abstract

This disclosure relates to a display device and an image display method, belonging to the field of display technology. The display device includes a display panel, a photosensitive device, and a control circuit. The display panel includes multiple sub-pixels; the photosensitive device is disposed on the display panel and is used to detect ambient light intensity. The control circuit is used to determine the target brightness of each sub-pixel in multiple colors based on the ambient light intensity determined by the ambient light intensity and acquired initial display data, and controls the display panel to display a target image based on the target brightness; the initial display data includes the initial grayscale of each sub-pixel in multiple colors. The display device and image display method of this disclosure can improve the problems of low grayscale loss and image distortion.

Description

Technical Field

[0001] This disclosure relates to the field of display technology, and more specifically, to a display device and an image display method. Background Technology

[0002] Currently, display devices are widely used in terminal devices such as mobile phones, televisions, tablets, and smartwatches. However, image distortion sometimes occurs during use, especially at low grayscale levels, where detail loss can occur.

[0003] It should be noted that the information disclosed in the background section above is only used to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0004] The purpose of this disclosure is to provide a display device and an image display method that can improve the problems of low grayscale loss and image distortion.

[0005] According to one aspect of this disclosure, a display device is provided, comprising:

[0006] The display panel includes multiple sub-pixels;

[0007] A photosensitive device, located on the display panel, is used to detect ambient light intensity;

[0008] A control circuit is configured to determine the target brightness of each sub-pixel in multiple colors based on the ambient light intensity reflected by the display panel as determined by the ambient light illuminance and the acquired initial display data, and to control the display panel to display a target image based on the target brightness; the initial display data includes the initial grayscale of each sub-pixel in multiple colors; the ambient light intensity, the initial grayscale, and the target brightness satisfy the following formula:

[0009]

[0010]

[0011] L j Let be the target brightness at gray level j, and j∈(0,2). n -1); L max L represents the maximum brightness of the display panel. AK The ambient light intensity is as described; J AK The ambient light intensity is the gray level at the first gamma; gamma_o ​​is the first gamma; gamma_pk is the second gamma; n is a positive integer.

[0012] In one exemplary embodiment of this disclosure, the ambient illuminance and the ambient light intensity satisfy the following formula:

[0013] L A =S.ALS Data (3)

[0014] L A Ambient light intensity; ALS Data The ambient light intensity; S is the slope coefficient.

[0015] In one exemplary embodiment of this disclosure, the ambient light illuminance is the average value of at least a portion of the multiple illuminance sample values ​​detected by the photosensitive device.

[0016] In one exemplary embodiment of this disclosure, the control circuit presets multiple lookup tables, each of which includes 2 n The target brightness is different in at least some of the different lookup tables; the different lookup tables correspond to different ambient light brightness.

[0017] In one exemplary embodiment of this disclosure, the display panel includes a frame covering the edge of the display panel, and the frame is provided with light-transmitting holes;

[0018] The photosensitive device is located inside the frame and is positioned corresponding to the light-transmitting hole.

[0019] In one exemplary embodiment of this disclosure, the frame is provided with a neutral attenuator covering the light-transmitting hole.

[0020] According to one aspect of this disclosure, an image display method for a display device is provided, the display device including a display panel having a plurality of sub-pixels; the image display method includes:

[0021] Detect the ambient light level of the environment in which the display panel is located;

[0022] The ambient light brightness reflected by the display panel is determined based on the ambient light illuminance.

[0023] The target brightness of each sub-pixel is determined based on the ambient light intensity; the target brightness satisfies the following formula:

[0024]

[0025]

[0026] L j Let be the target brightness at gray level j, and j∈(0,2). n -1); L max L represents the maximum brightness of the display panel. AK The ambient light intensity is as described; JAK The ambient light intensity is the grayscale value at the first gamma; gamma_o ​​is the first gamma; gamma_pk is the second gamma; n is a positive integer;

[0027] The target image is displayed on the display panel according to the target brightness.

[0028] In one exemplary embodiment of this disclosure, detecting the ambient illuminance of the environment in which the display panel is located includes:

[0029] Multiple ambient light samples were obtained by detecting ambient light multiple times;

[0030] The average value of at least a portion of the ambient light sample values ​​is taken as the ambient light illuminance.

[0031] In one exemplary embodiment of this disclosure, the average value of at least a portion of ambient light sample values ​​is used as the ambient illuminance; including:

[0032] Calculate the mean and standard deviation of each ambient light sample value;

[0033] Calculate the average value of ambient light samples within a specified range as the ambient light illuminance.

[0034] The specified interval is (μ-2σ, μ+2σ);

[0035] μ is the average value of each ambient light sample value; σ is the standard deviation of each ambient light sample value.

[0036] In one exemplary embodiment of this disclosure, determining the ambient light brightness reflected by the display panel based on the ambient light illuminance includes:

[0037] The ambient light intensity reflected by the display panel is calculated based on the ambient light illuminance and formula (3); formula (3) is as follows:

[0038] L A =S.ALS Data (3)

[0039] L A Ambient light intensity; ALS Data The ambient light intensity is denoted as ; S is the slope coefficient.

[0040] In one exemplary embodiment of this disclosure, the target brightness of each sub-pixel is determined based on the ambient light brightness; including:

[0041] Based on the ambient light intensity, a lookup table corresponding to the ambient light intensity is selected from multiple lookup tables as the target lookup table; the lookup table includes 2 nA brightness level, wherein the brightness level of the target lookup table is the target brightness level; at least some of the brightness levels in different lookup tables are different.

[0042] In one exemplary embodiment of this disclosure, the image display method further includes:

[0043] Set m increments for ambient light intensity and m+1 increments for ambient light illuminance. Use the kth ambient light illuminance as the lower comparison value for the kth ambient light intensity and the (k+1)th ambient light illuminance as the upper comparison value for the kth ambient light intensity. The lookup table corresponding to the kth ambient light intensity is the kth lookup table. m≥k≥1, m>2.

[0044] Based on the ambient light intensity, a lookup table corresponding to the ambient light intensity is selected as the target lookup table from multiple lookup tables; including:

[0045] If the current ambient light intensity is the kth ambient light intensity, the target lookup table is the kth lookup table;

[0046] The ambient illuminance is compared with the upper comparison value of the kth ambient light intensity in real time, and the ambient illuminance is compared with the lower comparison value of the kth ambient light intensity in real time.

[0047] If ALS Data ≥ALS Data(k+1) (1+Q), then the (k+1)th lookup table will be used as the target lookup table;

[0048] ALS Data The ambient light intensity; ALS Data(k+1) The ambient illuminance is the (k+1)th illuminance.

[0049] 0.5 > Q > 0.

[0050] In one exemplary embodiment of this disclosure, the image display method further includes: if ALS Data ≤ALS Data(k-1) (1-W), then the (k-1)th lookup table is used as the target lookup table;

[0051] ALS Data(k-1) The ambient illuminance is the (k-1)th illuminance; 0 > W > 0.5.

[0052] In one exemplary embodiment of this disclosure, Q = W = 0.2.

[0053] In one exemplary embodiment of this disclosure, the image display method further includes:

[0054] If ALS Data ≥ALS Data(m+1) (1+Q), then the k-th lookup table is maintained as the target lookup table;

[0055] If ALS Data ≤ALS Data(m-1) If (1-W), then the k-th lookup table is maintained as the target lookup table.

[0056] The display device and image display method disclosed herein no longer directly display the image based on the initial grayscale, but instead redetermine the target brightness of each sub-pixel based on the ambient light brightness obtained by detecting the ambient light, and display the target image based on the target brightness. Since the target brightness and the ambient light brightness satisfy formulas (1) and (2), the influence of ambient light on the visual effect can be compensated, and the problem of loss of levels and image distortion at low grayscale caused by ambient light can be improved.

[0057] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this disclosure. Attached Figure Description

[0058] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure. It is obvious that the drawings described below are merely some embodiments of this disclosure, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0059] Figure 1 This is a schematic diagram of one embodiment of the display device disclosed herein.

[0060] Figure 2 This is a schematic diagram of a display panel in one embodiment of the display device of this disclosure.

[0061] Figure 3 This is a schematic diagram showing the installation of the frame and the photosensitive device in one embodiment of the display device disclosed herein.

[0062] Figure 4 This is a flowchart illustrating the determination of a lookup table for one embodiment of the display device of this disclosure.

[0063] Figure 5 This is a graph showing the relationship between ambient light brightness and ambient light illuminance in one embodiment of the display device disclosed herein. Detailed Implementation

[0064] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, they are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the exemplary embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and therefore detailed descriptions of them will be omitted. Furthermore, the drawings are merely illustrative of this disclosure and are not necessarily drawn to scale.

[0065] The terms “a,” “one,” “the,” “the,” and “at least one” are used to indicate the presence of one or more elements / components / etc.; the terms “including” and “having” are used to indicate an open-ended inclusion and to mean that there may be other elements / components / etc. in addition to the listed elements / components / etc.; the terms “first,” “second,” and “third,” etc., are used only as markers and are not a limitation on the number of objects.

[0066] This disclosure provides a display device, such as... Figures 1-3 As shown, the display device may include a display panel 1, a photosensitive device 2, and a control circuit 3, wherein:

[0067] Display panel 1 includes multiple sub-pixels;

[0068] The photosensitive device 2 is located on the display panel 1 and is used to detect ambient light level;

[0069] The control circuit 3 is used to determine the target brightness of each sub-pixel in multiple colors based on the ambient light intensity reflected by the display panel 1 and the acquired initial display data, and to control the display panel 1 to display the target image according to the target brightness; the initial display data includes the initial grayscale of each sub-pixel in multiple colors; the ambient light intensity, the initial grayscale, and the target brightness satisfy the following formula:

[0070]

[0071]

[0072] L j Let be the target brightness at gray level j, and j∈(0,2). n -1); L max The maximum brightness of display panel 1; L AK Ambient light intensity; J AK The ambient light level is the grayscale at the first gamma; gamma_o ​​is the first gamma; gamma_pk is the second gamma; n is a positive integer.

[0073] The inventors discovered that when ambient light shines on a display device, some of the light is reflected by the display device. The brightness of the reflected light increases the brightness of the display device. However, the brightness difference between adjacent gray levels in low grayscale is small, making it difficult for the human eye to distinguish different gray levels in low grayscale due to the influence of ambient light, resulting in the loss of low grayscale levels and image distortion. The display device of this disclosure no longer displays the image directly based on the initial grayscale, but redetermines the target brightness of each sub-pixel based on the ambient light brightness obtained by detecting the ambient light, and displays the target image based on the target brightness. Since the target brightness and the ambient light brightness satisfy formulas (1) and (2), the influence of ambient light on the visual effect can be compensated, and the problem of loss of levels and image distortion in low grayscale caused by ambient light can be improved.

[0074] The display device disclosed herein will now be described in detail:

[0075] like Figures 1-3 As shown, the display device may include a display panel 1, a photosensitive device 2, and a control circuit 3, wherein:

[0076] Display panel 1 has multiple pixels, each pixel comprising three or more sub-pixels.

[0077] Display panel 1 can be a liquid crystal display panel (LCD), an organic light-emitting diode (OLED) display panel, or a Micro LED or Mini LED display panel; no special limitation is made here.

[0078] like Figure 2 As shown, taking a liquid crystal display panel as an example, it may include a liquid crystal display module PNL and a backlight module BLU. The liquid crystal display module PNL may include an array substrate TB and an opposing substrate FB disposed opposite each other, and may also include a liquid crystal layer LL disposed between the array substrate TB and the opposing substrate FB.

[0079] The liquid crystal display module (PNL) also includes pixel electrodes and a common electrode. The pixel electrode can be disposed on the array substrate TB, and the common electrode can be disposed on the array substrate TB or the opposing substrate FB. Each pixel can include a pixel electrode and its corresponding liquid crystal layer LL. The array substrate TB has a driving circuit, and the control circuit CU can control the voltage between the pixel electrode and the common electrode through the driving circuit, thereby controlling the degree of deflection of the liquid crystal molecules in the liquid crystal layer LL, and thus controlling the light transmittance of each sub-pixel, realizing the adjustment of the brightness of each sub-pixel, thereby realizing the adjustment of grayscale.

[0080] A liquid crystal display module (PNL) can be divided into a display area and a peripheral area outside the display area. The PNL can include pixel circuits connected to pixel circuits in the display area and peripheral circuits in the peripheral area. The peripheral circuits can include gate driving circuits and source driving circuits. The gate driving circuit can scan each pixel circuit and control its timing. The source driving circuit can transmit data signals to each pixel circuit, thereby controlling the voltage between the pixel electrode and the common electrode.

[0081] The backlight module BLU can be located on the side of the array substrate TB away from the opposing substrate FB. Under the control of the control circuit CU, the backlight module BLU can emit light towards the array substrate TB.

[0082] In some embodiments, the opposing substrate FB may include a color filter layer, which includes a plurality of light filters. A sub-pixel may include a light filter. Through the filtering effect of the light filter, a pixel emits monochromatic light, and different pixels may emit different colors.

[0083] like Figure 1 and Figure 3 As shown, the display device may also include a bezel 4, which may cover the edge of the display panel 1, with the edges of the liquid crystal display module PNL and the backlight module BLU located within the bezel 4. The bezel 4 may be provided with a light-transmitting hole 41 for transmitting ambient light.

[0084] The photosensitive device 2 can be disposed within the frame 4 and corresponding to the light-transmitting hole 41, allowing ambient light to shine through the light-transmitting hole 41 onto the photosensitive device 2. For example, the photosensitive device 2 may include a circuit board 22 and a photoelectric sensor 21 disposed on the circuit board 22. The photoelectric sensor 21 can correspond to the light-transmitting hole 41 and is used to sense ambient light. The circuit board 22 can be fixed within the frame 4. For example, the frame 4 may be provided with mounting holes 42, and the circuit board 22 can be detachably connected to the frame 4 by screws that mate with the mounting holes 42. Of course, the circuit board 22 can also be fixed within the frame 4 by adhesive or other means, without any special limitation.

[0085] In addition, to prevent the ambient light illuminance from exceeding the detection range of the photoelectric sensor 21, a neutral attenuator can be provided on the frame 4 to cover the light-transmitting hole 41. It can filter the light, but not for any specific color.

[0086] like Figure 1As shown, the control circuit 3 controls the display panel 1 to display images. It may include a main control circuit 31, a timing controller 34, a gamma circuit, a power supply circuit 32, and a backlight driving circuit 33. The main control circuit 31 can be a System-on-a-Chip (SoC) and can be connected to the timing controller 34, the power supply circuit 32, and the backlight driving circuit 33. The main control circuit 31 can receive or generate display data. The timing controller 34 generates driving signals based on the display data, controls the gate driving circuit to scan the pixel circuit through the driving signals, and controls the voltage of the pixel electrodes through the source driving circuit and the gamma circuit. Simultaneously, the main control circuit 31 can also control the brightness of the backlight module (BLU) through the backlight driving circuit 33. The power supply circuit 32 provides power to the control circuit 3. Furthermore, the control circuit 3 may also include a playback control circuit 35 connected to the main control circuit 31, which can respond to certain operations and control the image display through the main control circuit 31.

[0087] The photosensitive device 2 can be connected to the control circuit 3. For example, the circuit board 22 of the photosensitive device 2 is connected to the main control circuit 31 through its interface, and transmits the data detected by the device to the main control circuit 31.

[0088] The working principle of the display device of this disclosure is illustrated below with reference to the image display method:

[0089] The image display method disclosed herein may include steps S10-S40, wherein:

[0090] Step S10: Detect the ambient light level of the environment in which the display panel is located;

[0091] Step S20: Determine the ambient light brightness reflected by the display panel based on the ambient light illuminance;

[0092] Step S30: Determine the target brightness of each sub-pixel based on the ambient light intensity; the target brightness satisfies the following formula:

[0093]

[0094]

[0095] L j Let be the target brightness at gray level j, and j∈(0,2). n -1); L max The maximum brightness of the display device; L AK Ambient light intensity; J AK The ambient light intensity is represented by the grayscale value at the first gamma; gamma_o ​​represents the first gamma; gamma_pk represents the second gamma; and n is a positive integer.

[0096] Step S40: Control the display panel to display the target image according to the target brightness.

[0097] The following is a detailed explanation of each step:

[0098] In step S10, ambient light can be detected by the photosensor 2 to obtain the ambient illuminance. This detection can be performed in real-time or at set intervals. Furthermore, since the display device may be used in multiple scenarios with different ambient light conditions, and the ambient light itself may change even within the same scenario, the required ambient illuminance can be obtained based on multiple collected values, improving accuracy. For example:

[0099] In some embodiments of this disclosure, the ambient light level of the environment in which the display panel 1 is located is detected; i.e., step S10 may include:

[0100] Step S110: Detect ambient light multiple times to obtain multiple ambient light sample values.

[0101] Ambient light can be detected in real time by the photosensitive device 2, and the ambient light sample value can be output in real time. The ambient light sample value is the illuminance. Of course, sampling can also be performed at regular intervals, as long as data can be collected multiple times. For example, a fixed sampling period or number of samplings can be set. The ambient light sample values ​​collected within one sampling period or a certain number of samplings are used to calculate an ambient light illuminance.

[0102] Step S120: Take the average value of at least a portion of the ambient light sampling values ​​as the ambient light illuminance.

[0103] The ambient light sampling value detected by the photosensitive device 2 can be output to the main control circuit 31 of the control circuit 3 in order to eliminate some potentially excessively large or small sudden data. These data may be caused by sudden appearances of car headlights or human bodies blocking the view. If the impact of such changes is considered when displaying the image, it will cause the image to change too frequently, affecting the display effect.

[0104] Furthermore, in order to eliminate abnormal sampled values ​​and reduce the interference of abrupt changes in data, in some embodiments of this disclosure, considering that ambient light sampled values ​​follow a normal distribution, step S120 may include steps S1210-S1220, wherein:

[0105] Step S1210: Calculate the average value and standard deviation of each ambient light sample value.

[0106] It can calculate the average value μ of all ambient light samples within a sampling period or number of sampling times, and calculate the standard deviation σ. The specific calculation method is as follows:

[0107]

[0108]

[0109] x1-xn Let n be the number of ambient light sample values.

[0110] Step S1220: Calculate the average value of the ambient light sampled values ​​within the specified interval as the ambient light illuminance.

[0111] The specified interval can be (μ-2σ, μ+2σ), thus proposing ambient light sampling values ​​that are less than μ-2σ and greater than μ+2σ. Of course, 2σ can also be replaced with 3σ to reduce the amount of data to be discarded.

[0112] In addition, other methods such as box plots can be used to remove outlier sampled values, which will not be detailed here.

[0113] In step S20, given that the photosensitive device 2 and the display device are determined, the ambient illuminance and the ambient light brightness reflected by the display device have a linear relationship. Therefore, it is only necessary to determine the slope coefficient S to determine the ambient illuminance ALS. Data Determine the ambient light intensity L A Therefore, for a display device, by testing the ambient light brightness under two different ambient light levels, the slope coefficient S of the straight line reflecting the relationship between the two can be determined. Therefore, in some embodiments of this disclosure, step S120 may include:

[0114] like Figure 5 As shown, based on ambient light illuminance ALS Data The ambient light luminance L reflected by the display panel 1 is calculated using formula (3). A Formula (3) is as follows:

[0115] L A =S·ALS Data (3)

[0116] L A Ambient light intensity; ALS Data is the ambient illuminance; S is the slope coefficient S.

[0117] In some embodiments of this disclosure, a straight line reflecting the linear relationship between the two can be determined based on the above formula (3) and the ambient light brightness under multiple ambient light illuminances, and multiple illuminance intervals can be formed using multiple discrete ambient light illuminances. Each illuminance interval can correspond to an ambient light brightness. For example, the ambient light brightness corresponding to a point (e.g., the midpoint) in an illuminance interval can be taken as the ambient light brightness corresponding to all points in that illuminance interval.

[0118] In step S30, the display device contains at least three sub-pixels with different light-emitting colors, such as sub-pixels emitting red light (R), sub-pixels emitting green light (G), and sub-pixels emitting blue light (B). The brightness of each color sub-pixel needs to be re-determined, but in the same way. That is, the brightness of each color sub-pixel is no longer based on the initial grayscale level, but is first converted to the target brightness, and then the display panel 1 is controlled to display the image according to the target brightness.

[0119] The grayscale corresponding to the ambient light intensity at the first gamma can be determined based on the ambient light intensity and the maximum brightness of the display device, and then the grayscale corresponding to the second gamma can be redefined based on that grayscale. n The brightness of each gray level is the target brightness, which is the brightness of each gray level re-expressed. The target brightness can satisfy the following formula:

[0120]

[0121]

[0122] Among them, L j Let be the target brightness at gray level j, and j∈(0,2). n -1); n is a positive integer, for example, n = 8, then it includes 0-255, a total of 256 gray levels. L max The maximum brightness of display panel 1 itself, i.e., the maximum brightness of the display device; L AK Ambient light intensity; J AK The grayscale value for ambient light intensity at the first gamma.

[0123] gamma_o ​​is the first gamma, which can be 2.2. gamma_pk is the second gamma, which can be the same as the first gamma, and both can be 2.2. Of course, gamma_pk can also be different from gamma_o, depending on the user's color preference.

[0124] For any display device, its brightness and grayscale can satisfy the following formula:

[0125]

[0126] Correspondingly,

[0127] L in formula (4) j Let be the brightness corresponding to gray level j under gamma_o, where gamma_o ​​can be 2.2. n is a positive integer, for example, n = 8, which includes 0-255, a total of 256 gray levels. The above formulas (1) and (2) are consistent with formulas (4) and (5).

[0128] L max+L AK The maximum brightness of the display device that can be visually perceived is the sum of the maximum brightness of the display device itself and the ambient light brightness.

[0129] The visual brightness of grayscale j under gamma_pk is subtracted from the ambient light brightness L. AK Then, the brightness L of the display panel 1 itself can be obtained. j ; 2 n J is removed from the grayscale levels where the ambient light intensity is at the first gamma. AK The grayscale after 2 n The proportion of each gray level.

[0130] Furthermore, in some embodiments of this disclosure, L based on formulas (2) and (5) above can be obtained as formula (5). j The gray level j of the first gamma_0 is obtained p＇ Regarding j p＇ Rounding to the nearest integer, we get j. p Therefore, it can be determined based on j p and L j The correspondence is used to obtain a new gamma curve, that is, a new gamma, which is used by control circuit 3.

[0131] When determining the target brightness, it can be calculated in real time using the formulas (1) and (2) mentioned above. However, this involves a large amount of computation, which is not conducive to improving efficiency and reducing energy consumption. Therefore, multiple lookup tables can be pre-established for different ambient light intensities, and each lookup table can include 2 n A brightness value, where n is a positive integer, for example, n = 8, 2 n -1 can be 255, plus 0 grayscale, for a total of 256 brightness levels. For example, it can be the brightness of the target lookup table as the target brightness; at least some brightness levels are different in different lookup tables. One lookup table corresponds to one ambient light brightness. After determining the ambient light brightness, as long as the corresponding lookup table is found, the target brightness corresponding to each initial grayscale can be obtained. Thus, the display data can be converted to obtain data reflecting the initial grayscale and target brightness.

[0132] Meanwhile, since ambient light is not constant, the display device needs to continuously filter the lookup table as the ambient light level changes during the display process. However, if a new lookup table is invoked due to sudden changes in ambient light, such as car headlights or human occlusion, it will cause visually perceptible flickering of the image, affecting the user's viewing experience. Therefore, in some embodiments of this disclosure, the image display method may further include:

[0133] Step S50: Set m increments of ambient light brightness and m+1 increments of ambient light illuminance. The lookup table corresponding to the kth ambient light brightness can be defined as the kth lookup table, and the lookup table corresponding to the k+1th ambient light brightness is the k+1th lookup table; m≥k≥1, m>2.

[0134] The difference between two adjacent ambient light intensities remains constant, meaning the ambient light intensities can follow an arithmetic sequence. Similarly, the difference between two adjacent ambient illuminances remains constant, meaning the ambient illuminances can follow an arithmetic sequence. Of course, ambient light intensities and illuminances can also follow other distribution patterns instead of arithmetic sequences.

[0135] Based on m+1 ambient illuminance values, m illuminance intervals can be obtained. The boundary points of an illuminance interval are two adjacent ambient illuminance values. For example, the lower boundary point of the k-th illuminance interval is the k-th ambient illuminance value, and the upper boundary point is the k+1-th ambient illuminance value. All points within the k-th illuminance interval can correspond to the same ambient light intensity, which is the k-th ambient light intensity value, thus reducing the computational load.

[0136] The k-th ambient illuminance can be defined as the lower comparison value of the k-th ambient luminance, and the (k+1)-th ambient illuminance can be defined as the upper comparison value of the k-th ambient luminance.

[0137] The lookup table can be determined iteratively, using an interleaving approach. Specifically:

[0138] like Figure 4 and Figure 5 As shown, with the k-th ambient light luminance as the current ambient light luminance and the k-th lookup table as the current lookup table, the display device can display the image according to the target luminance of the k-th lookup table. Simultaneously, the control circuit 3 can compare the ambient light illuminance detected by the sensor with the upper and lower comparison values ​​of the k-th ambient light luminance, and determine the target lookup table based on the comparison results. Specifically:

[0139] If ALS Data ≥ALS Data ( k+1) If (1+Q), then the (k+1)th lookup table will be used as the target lookup table.

[0140] ALS Data ALS refers to the detected ambient light intensity. Data(k+1) This is the (k+1)th ambient illuminance, i.e., the upper comparison value of the kth ambient light intensity. 0.5 > Q > 0. That is to say, in ALS... Data Greater than ALS Data(k+1) If the exceedance reaches Q, the k-th lookup table corresponding to the k-th ambient light intensity is no longer used; instead, the (k+1)-th lookup table corresponding to the (k+1)-th ambient light intensity is used as the target lookup table. If the exceedance does not reach Q, the k-th lookup table is still used as the target lookup table.

[0141] If ALS Data ≤ALS Data(k-1) If (1-W), then the (k-1)th lookup table will be used as the target lookup table.

[0142] ALS Data(k-1) This is the lower comparison value of the (k-1)th ambient illuminance, i.e., the kth ambient light intensity; 0 > W > 0.5. In other words, in ALS... Data Less than ALS Data(k+1) If the magnitude of the light intensity is less than Q, the k-th lookup table corresponding to the k-th ambient light intensity will no longer be used, but the (k-1)-th lookup table corresponding to the (k-1)-th ambient light intensity will be used as the target lookup table; if the magnitude is not reached, the k-th lookup table will still be used as the target lookup table.

[0143] Therefore, the lookup table can be continuously adjusted based on changes in ambient light, and it can remain unchanged when the ambient light changes abruptly, thus avoiding flickering.

[0144] The values ​​of Q and W mentioned above can be equal. According to experimental analysis, when both are equal to 0.2, the problem of image distortion at low gray levels can be avoided, and flickering can be prevented. Of course, Q and W can also be unequal.

[0145] like Figure 4 As shown, in some embodiments of this disclosure, the ambient light intensity detected by the sensing device is first compared with the upper comparison value of the k-th ambient light intensity. If ALS Data ≥ALS Data(k+1) If (1+Q), then the (k+1)th lookup table is used as the target lookup table, and the ambient illuminance is no longer compared with the lower comparison value of the kth ambient illuminance.

[0146] If ALS Data <ALS Data(k+1) (1+Q), then compare the ambient illuminance with the lower bound of the kth ambient illuminance. If ALS Data ≥ALS Data(k-1) If (1+W), then the (k-1)th lookup table is used as the target lookup table.

[0147] In addition, such as Figure 4 As shown, in some embodiments of this disclosure, based on the above comparison process, the following steps may also be included:

[0148] If ALS Data ≥ALS Data(m+1) If (1+Q), then the k-th lookup table is maintained as the target lookup table.

[0149] If ALS Data ≤ALS Data0If (1-W), then the k-th lookup table is maintained as the target lookup table.

[0150] In other words, in ambient light illuminance ALS Data If the value is extremely low or extremely high, it indicates that there may be an error in the data. In this case, the current target lookup table can be kept unchanged, and the comparison process described above can be continued.

[0151] It should be noted that, since the display device has sub-pixels of multiple colors, for each color, there exists the aforementioned lookup table and its target brightness. In other words, the initial grayscale of the display data includes the initial grayscale of multiple colors, and the initial grayscale of sub-pixels of the same color is located in the same lookup table. Of course, the target grayscale of all sub-pixels can also be placed in the same lookup table.

[0152] In step S40, the target brightness is not the brightness controlled by the pixel electrode voltage when the display device finally displays the image. That is, the target brightness is not the final executed brightness, but a conversion of the brightness based on the initial grayscale by the control circuit. After obtaining the target brightness, the control device can send it to the timing controller 34. The timing controller 34 can control the gamma circuit and the source drive circuit to generate the executed brightness, and then convert the executed brightness into the pixel electrode voltage, so as to control the display panel 1 to display the target image according to the target brightness. In this process, gamma correction can be performed on the target brightness through the gamma circuit, that is, under the first gamma, the specified brightness corresponding to each target brightness is determined. In other words, the display device and its image display method of this disclosure perform two gamma corrections. The first is the conversion of the display data by the control circuit 3, and the second is the conversion by the gamma circuit and the source drive circuit.

[0153] It should be noted that although the steps of the image display method in this disclosure are described in a specific order in the accompanying drawings, this does not require or imply that these steps must be performed in that specific order, or that all the steps shown must be performed to achieve the desired result. Additional or alternative steps may be omitted, multiple steps may be combined into one step, and / or one step may be broken down into multiple steps.

[0154] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this disclosure are indicated by the appended claims.

Claims

1. A display device, characterized in that, include: The display panel includes multiple sub-pixels; A photosensitive device, located on the display panel, is used to detect ambient light intensity; A control circuit is configured to determine the target brightness of each sub-pixel in multiple colors based on the ambient light intensity reflected by the display panel as determined by the ambient light illuminance and the acquired initial display data, and to control the display panel to display a target image based on the target brightness; the initial display data includes the initial grayscale of each sub-pixel in multiple colors; the ambient light intensity, the initial grayscale, and the target brightness satisfy the following formula: L j Let be the target brightness at gray level j, and j∈(0,2). n -1); L max L represents the maximum brightness of the display panel. AK The ambient light intensity is as described; J AK The ambient light intensity is the gray level at the first gamma; gamma_o ​​is the first gamma; gamma_pk is the second gamma; n is a positive integer.

2. The display device according to claim 1, characterized in that, The ambient illuminance and the ambient light intensity satisfy the following formula: L A S-ALS Data (3) L A Ambient light intensity; ALS Data The ambient light intensity; S is the slope coefficient.

3. The display device according to claim 1, characterized in that, The ambient light illuminance is the average value of at least a portion of the multiple illuminance sample values ​​detected by the photosensitive device.

4. The display device according to claim 1, characterized in that, The control circuit presets multiple lookup tables, and any one of the lookup tables includes 2... n The target brightness is different in at least some of the different lookup tables; the different lookup tables correspond to different ambient light brightness.

5. The display device according to claim 1, characterized in that, The display device further includes a frame covering the edge of the display panel, the frame having light-transmitting holes; The photosensitive device is located inside the frame and is positioned corresponding to the light-transmitting hole.

6. The display device according to claim 5, characterized in that, The frame is provided with a neutral attenuation sheet that covers the light-transmitting hole.

7. An image display method for a display device, characterized in that, The display device includes a display panel having a plurality of sub-pixels; the image display method includes: Detect the ambient light level of the environment in which the display panel is located; The ambient light brightness reflected by the display panel is determined based on the ambient light illuminance. The target brightness of each sub-pixel is determined based on the ambient light intensity; the target brightness satisfies the following formula: L j Let be the target brightness at gray level j, and j∈(0,2). n -1); L max L represents the maximum brightness of the display panel. AK The ambient light intensity is as described; J AK The ambient light intensity is the grayscale value at the first gamma; gamma_o ​​is the first gamma; gamma_pk is the second gamma; n is a positive integer; The target image is displayed on the display panel according to the target brightness.

8. The image display method according to claim 7, characterized in that, Detecting the ambient light level of the environment in which the display panel is located; including: Multiple ambient light samples were obtained by detecting ambient light multiple times; The average value of at least a portion of the ambient light sample values ​​is taken as the ambient light illuminance.

9. The image display method according to claim 8, characterized in that, The average value of at least a portion of the ambient light samples is taken as the ambient illuminance; including: Calculate the mean and standard deviation of each ambient light sample value; Calculate the average value of ambient light samples within a specified range as the ambient light illuminance. The specified interval is (μ-2σ, μ+2σ); μ is the average value of each ambient light sample value; σ is the standard deviation of each ambient light sample value.

10. The image display method according to claim 7, characterized in that, Determining the ambient light brightness reflected by the display panel based on the ambient light illuminance; including: The ambient light intensity reflected by the display panel is calculated based on the ambient light illuminance and formula (3); formula (3) is as follows: L A S-ALS Data (3) L A Ambient light intensity; ALS Data The ambient light intensity is denoted as ; S is the slope coefficient.

11. The image display method according to claim 7, characterized in that, Determining the target brightness of each sub-pixel based on the ambient light brightness; including: Based on the ambient light intensity, a lookup table corresponding to the ambient light intensity is selected from multiple lookup tables as the target lookup table; the lookup table includes 2 n -1 brightness, the brightness of the target lookup table is the target brightness; at least some of the brightness in different lookup tables are different.

12. The image display method according to claim 11, characterized in that, The image display method further includes: Set m increments for ambient light intensity and m+1 increments for ambient light illuminance. Use the kth ambient light illuminance as the lower comparison value for the kth ambient light intensity and the (k+1)th ambient light illuminance as the upper comparison value for the kth ambient light intensity. The lookup table corresponding to the kth ambient light intensity is the kth lookup table. m≥k≥1, m>2. Based on the ambient light intensity, a lookup table corresponding to the ambient light intensity is selected as the target lookup table from multiple lookup tables; including: If the current ambient light intensity is the kth ambient light intensity, the target lookup table is the kth lookup table; The ambient illuminance is compared with the upper comparison value of the kth ambient light intensity in real time, and the ambient illuminance is compared with the lower comparison value of the kth ambient light intensity in real time. If ALS Data ≥ALS Data ( k+1) (1+Q), then the (k+1)th lookup table will be used as the target lookup table; ALS Data The ambient light intensity; ALS Data ( k+1) The ambient illuminance is the (k+1)th illuminance. 0.5＞Q＞0。 13. The image display method according to claim 12, characterized in that, The image display method further includes: if ALS Data ≤ALS Data ( k-1) (1-W), then the (k-1)th lookup table is used as the target lookup table; ALS Data ( k-1) The ambient illuminance is the (k-1)th illuminance; 0 > W > 0.

5.

14. The image display method according to claim 13, characterized in that, Q = W = 0.

2.

15. The image display method according to claim 13, characterized in that, The image display method further includes: If ALS Data ≥ALS Data ( m+1) (1+Q), then the k-th lookup table is maintained as the target lookup table; If ALS Data ≤ALS Data ( m-1) If (1-W), then the k-th lookup table is maintained as the target lookup table.

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