TWI740715B - Grayscale generating circuit and method - Google Patents

Abstract

A grayscale generating circuit and a method thereof are provided. The method includes steps of: dividing a illuminable time of a frame period into a plurality of illuminable unit times; selecting parts of the illuminable unit times as first light-emitting driving unit times according to high bit values of brightness data; selecting parts of the illuminable unit times as second light-emitting driving unit times that do not be overlapped with the first light-emitting driving unit times according to low bit values of the brightness data; determining a first driving current to a display device within each of the first light-emitting driving unit times; determining that a second driving current is supplied to the display device within only one of the second light-emitting driving unit times or the second driving current is distributed and supplied within the second light-emitting driving unit times.

Description

Grayscale generating circuit and method

The present invention relates to a gray-scale generation circuit and method, in particular to a gray-scale generation circuit and method suitable for displays.

Generally, the frequency at which the screen of a light emitting diode (LED) display changes is defined as the frame change rate, and its reciprocal is the frame change period. For example, when the frame change rate is 60 Hz, the frame change period is 1/60 sec. Ideally, the entire frame change period can be used to light up the LED, but considering synchronization or ghosting time in scanning applications or circuit limitations, in fact there will be some time during the entire frame change period that cannot be used for light emission.

With the development of LED displays, the requirements for the number of gray levels are getting higher and higher (the value of n is getting larger and larger), and the number of driving chips is reduced by increasing the number of scans. Therefore, the time for each LED to be allocated for display during a frame change period is getting shorter and shorter. For example, when there is no scanning originally, each LED can use the entire luminous time in the frame change period to display, but When using 4 scans, the usable display time of each LED becomes 1/4, which means that if the same number of gray scales is to be maintained, the length of the light-emitting unit time must be shortened to a quarter.

Theoretically, by greatly shortening the length of light-emitting unit time, it can meet the requirements of high scan number and high gray-scale number. However, in practical applications, considering the parasitic effect on the light board and the physical limitation of the driving circuit itself, the shorter the light-emitting unit time length is , The more serious the non-ideal phenomena, such as low gray scale unevenness or low gray scale color shift.

Aiming at the shortcomings of the prior art, a grayscale generation method is provided, which is suitable for displays. The frequency at which the display screen changes is defined as the frame change rate. The reciprocal of the frame change rate is the frame change period. The grayscale generation method includes the following steps: According to the high-bit number, low-bit number or both of the brightness data of the display, it is determined to divide the light-emitting time of the frame change period into m light-emitting unit times, where m is an integer value, Represents the number of light-emitting unit times; according to the high bit value of the brightness data, x light-emitting unit times are selected from m light-emitting unit times, where x is an integer value not greater than m, and x light-emitting unit times Each of them is used as the first light-emitting drive unit time; according to the low-bit value of the brightness data, y light-emitting unit times are selected from m light-emitting unit times, where y is an integer value not greater than m, and y Each of the light-emitting unit times is used as the second light-emitting driving unit time, and the second light-emitting driving unit time does not overlap with the first light-emitting driving unit time; the first driving current of the driving signal is supplied to each first light-emitting driving unit time A display; and a second driving current for determining the driving signal according to the low-bit value of the brightness data, wherein a second driving current is determined according to the low-bit value of the brightness data, wherein the second driving current is within a single second light-emitting driving unit time Supply, or distribute the supply within a plurality of second light-emitting driving unit times, and the second driving current is not greater than the first driving current.

In one embodiment, the grayscale generation method further includes the following steps: determining the minimum value of m according to the number of high bits of the luminance data, expressed as an equation: m=2 ^a , where a represents the high bits of the luminance data number.

In one embodiment, the grayscale generation method further includes the following steps: determining the maximum value of m according to the number of high bits and the number of low bits of the luminance data, expressed by the equation: m=(2 ^a -1)+ (2 ^b -1), where a represents the number of high bits of the luminance data, and b represents the number of low bits of the luminance data.

，其中，Is代表第二驅動電流，K代表亮度資料的低位元值，b代表亮度資料的低位元數，I代表一固定電流。第一驅動電流值等於固定電流值。 In one embodiment, the grayscale generation method further includes the following steps: determining the second driving current according to the low-bit value and the low-bit number of the luminance data, expressed as an equation:

, Where Is represents the second drive current, K represents the low-bit value of the brightness data, b represents the low-bit number of the brightness data, and I represents a fixed current. The first drive current value is equal to the fixed current value.

In one embodiment, the gray-scale generation method further includes the following steps: preset and fix g of m light-emitting unit times as high-bit light-emitting unit times and fix h as low-bit light-emitting unit times , Where g and h are integer values not greater than m, and any of the g light-emitting unit times does not overlap with any of the h light-emitting unit times; according to the high-bit value of the brightness data, Select x luminous unit times from g luminous unit times, where x is an integer value not greater than g; and according to the low-bit value of the brightness data, select y luminous unit times from h luminous unit times , Where y is an integer value not greater than h.

In one embodiment, the grayscale generation method further includes the following steps: according to the number of high bits of the brightness data, a preset g value is expressed as an equation: g=2 ^a -1, where a represents the high bit of the brightness data Yuan number.

In one embodiment, the grayscale generation method further includes the following steps: preset h according to the number of low bits of the luminance data, where the h value falls within a numerical range from ^{1 to (2 b -1), h} The minimum value is 1, and the maximum value of h is (2 ^b -1), where b represents the number of low bits of the luminance data.

In one embodiment, the grayscale generation method further includes the following steps: dividing a first scan driving signal in the driving signal into a plurality of first scan segments; dividing a second scan driving signal in the driving signal into a plurality of The second scanning segment; after scanning one of the first scanning segments of the plurality of first scanning segments, wait for a ghost image elimination time; and after scanning one of the second scanning segments of the plurality of second scanning segments, waiting for ghost images Eliminate the time, and then return to the previous step to scan another first scan segment among the multiple first scan segments until all the multiple first scan segments and the multiple second scan segments have been scanned.

In addition, the present invention provides a grayscale generating circuit suitable for displays. The frequency at which the display screen changes is defined as the frame change rate. The reciprocal of the frame change rate is the frame change period. The gray-scale generation circuit includes a frame-changing period division circuit, a light-emitting time determination circuit, and a drive current distribution circuit. The frame-changing period division circuit is configured to divide the light-emitting time of the frame-changing period into m light-emitting unit times according to the number of high bits, the number of low bits, or both of the brightness data of the display, where m is an integer value, representing The number of light-emitting units per time. The light-emitting time determination circuit is connected to the frame-changing period division circuit and the display. The light emitting time determination circuit is configured to select x light emitting unit times from m light emitting unit times according to the high bit value of a luminance data of the display, and to select from m light emitting unit times according to the low bit value of the luminance data Select y light-emitting unit times, where x and y are integer values not greater than m, each of x light-emitting unit times is used as the first light-emitting drive unit time, and each of y light-emitting unit times is used as The second light-emitting drive unit time. The first light-emitting driving unit time and the second light-emitting driving unit time do not overlap. The driving current distribution circuit is connected to the light-emitting time judging circuit and the display. The driving current distribution circuit is configured to supply the first driving current of the driving signal to the display within each first light-emitting driving unit time. The driving current distribution circuit is configured to determine the second driving current of the driving signal according to the low bit value of the luminance data. The driving current distribution circuit is configured to then determine whether to supply the second driving current of the driving signal within a single second light-emitting driving unit time, or to distribute and supply the second driving current to the display within a plurality of second light-emitting driving unit times. The second driving current is not greater than the first driving current.

In one embodiment, the frame-changing period dividing circuit determines the minimum value of m according to the number of high bits of the luminance data, expressed as an equation: m=2 ^a , where a represents the number of high bits of the luminance data.

In one embodiment, the frame-changing period division circuit determines the maximum value of m according to the number of high bits and the number of low bits of the luminance data, which is expressed by the equation: m=(2 ^a -1)+(2 ^b -1) , Where a represents the number of high bits of the luminance data, and b represents the number of low bits of the luminance data.

，其中，Is代表第二驅動電流，K代表亮度資料的低位元值，b代表亮度資料的低位元數，I代表一固定電流。第一驅動電流值等於固定電流值。 In one embodiment, the driving current distribution circuit is configured to determine the second driving current according to the low-bit value and the low-bit number of the luminance data, which is expressed by the equation:

, Where Is represents the second drive current, K represents the low-bit value of the brightness data, b represents the low-bit number of the brightness data, and I represents a fixed current. The first drive current value is equal to the fixed current value.

In one embodiment, the frame conversion period division circuit is configured to preset g of the m light-emitting unit times with g as the high-bit light-emitting unit time and fixed h as the low-bit light-emitting unit time, where g, h is an integer value not greater than m, and any one of the g light-emitting unit times does not overlap with any one of the h light-emitting unit times. The light-emitting time determination circuit selects x light-emitting unit times from g light-emitting unit times according to the high bit value of the brightness data. The light-emitting time determination circuit selects y light-emitting unit times from h light-emitting unit times according to the low-bit value of the brightness data. Among them, x is an integer value not greater than g, and y is an integer value not greater than h.

In one embodiment, the frame-changing period dividing circuit is based on the number of high bits of the luminance data, and the preset g value is expressed as an equation: g=2 ^a -1, where a represents the number of high bits of the luminance data.

In one embodiment, the frame-changing period dividing circuit uses a preset value of h according to the number of low-order bits of the luminance data, where the value of h falls ^{within the value range of 1 to (2 b} -1), and the minimum value of h is 1, h The maximum value is (2 ^b -1), where b represents the number of low bits of the luminance data.

In one embodiment, the scan control circuit of the display is connected to the display and the grayscale generation circuit. A first scan driving signal among the driving signals is divided into a plurality of first scan segments. A second scan driving signal among the driving signals is divided into a plurality of second scan segments. The scan control circuit is configured to scan one of the first scan segments of the plurality of first scan segments, and then after waiting for a ghost image elimination time, scan one of the second scan segments of the plurality of second scan segments, and then wait for ghost images After the elimination time, another first scan segment among the plurality of first scan segments is scanned, in this way, all the plurality of first scan segments and the plurality of second scan segments are alternately scanned.

In order to further understand the features and technical content of the present invention, please refer to the following detailed description and drawings about the present invention. However, the drawings provided are only for reference and description, and It is not intended to limit the present invention.

S101~S115, S201~S219: steps

10: Change frame period division circuit

20: Luminous time judgment circuit

30: Drive current distribution circuit

TS: Can illuminate unit time

Tcycle: Can light up time

I: fixed current

Toff: Ghost elimination time

Sc11: The first paragraph of the first scan

Sc21: The first segment of the second scan

Sc12: The second paragraph of the first scan

Sc22: The second paragraph of the second scan

FIG. 1 is a flowchart of the steps of the grayscale generation method according to the first embodiment of the present invention.

FIG. 2 is a block diagram of the grayscale generating circuit according to the first embodiment of the present invention.

FIG. 3 is a diagram of the relationship between driving current and time in the grayscale generation method of the first embodiment of the present invention.

4 is a diagram of the relationship between driving current and time in the gray-scale generation method of the first embodiment of the present invention.

FIG. 5 is a flow chart of the steps of the grayscale generation method according to the second embodiment of the present invention.

FIG. 6 is a block diagram of a grayscale generating circuit according to a second embodiment of the present invention.

FIG. 7 is a diagram showing the relationship between driving current and time in the grayscale generation method of the second embodiment of the present invention.

FIG. 8 is a diagram of the relationship between driving current and time in the grayscale generation method of the second embodiment of the present invention.

FIG. 9 is a diagram showing the relationship between the driving current and the time of the segment scanning of the driving signal of the gray-scale generating circuit according to the third embodiment of the present invention.

The following are specific specific examples to illustrate the implementation of the present invention. Those skilled in the art can understand the advantages and effects of the present invention from the content disclosed in this specification. The present invention can be implemented or applied through other different specific embodiments, and various details in this specification can also be based on different viewpoints and applications, and various modifications and changes can be made without departing from the concept of the present invention. In addition, the drawings of the present invention are merely schematic illustrations, and are not drawn according to actual dimensions, and are stated in advance. the following The implementation manners will further describe the related technical content of the present invention in detail, but the disclosed content is not intended to limit the protection scope of the present invention. In addition, the term "or" used in this article may include any one or a combination of more of the associated listed items depending on the actual situation.

Please refer to FIGS. 1 to 3, in which FIG. 1 is a flowchart of the steps of a grayscale generation method according to a first embodiment of the present invention; FIG. 2 is a block diagram of a grayscale generation circuit according to the first embodiment of the present invention; The relationship between the driving current and the time of the gray-scale generation method of the first embodiment of the invention.

As shown in FIG. 1, the grayscale generation method of this embodiment includes steps S101 to S115. The execution order, frequency and content of these steps can be appropriately omitted or adjusted according to actual needs, and the present invention is not limited to the examples of this embodiment.

The steps S101 to S115 of the gray-scale generation method of this embodiment can be performed by, for example, but not limited to, the gray-scale generation circuit shown in FIG. 2 to be suitable for displays. The frequency at which the display screen changes is defined as the frame change rate, and the reciprocal of the frame change rate is the frame change period. In fact, there will be some time in the entire frame change period that cannot be used to emit light. The Tcycle shown in Figure 3 represents a frame change. The luminous time within the cycle.

In step S101, the frame change period dividing circuit 10 of the grayscale generating circuit shown in FIG. 2 (which can be included in the display driving circuit) is used, according to the number of high bits and low bits in the total number of bits n of the brightness data of the display. The number of elements or both is used to determine m light-emitting unit time, where n represents the number of bits of the brightness data, and m represents the number of light-emitting unit time.

For example, using the frame conversion period dividing circuit 10 of the grayscale generating circuit shown in FIG. 2, the minimum value of m is determined according to the number of high bits of the luminance data, expressed by the equation: m=2 ^a , where a Represents the number of high bits of the brightness data. As shown in Figure 3, the luminance data has 4 bits of high bits, and the number of TS per unit time that can be illuminated is calculated as m=2 ^a =2 ⁴ =16.

In step S103, use the frame changing period dividing circuit 10 of the grayscale generating circuit shown in FIG. 2 to divide the light-emitting time of the frame changing period into m light-emitting unit times, where m is an integer value and represents the light-emitting unit The amount of time, for example, as shown in Figure 3, the light-emitting time Tcycle of the frame changing period is divided into 16 light-emitting unit times TS, expressed by the equation: TS=Tcycle/16, which is 4 times the traditional light-emitting unit time TS0 , Expressed as an equation: TS0=Tcycle/(2 ⁶ )=Tcycle/(64), where TS0 represents the traditional light-emitting unit time.

In step S105, the light-emitting time determination circuit 20 of the grayscale generating circuit shown in FIG. 2 is used to select x light-emitting unit times from m light-emitting unit times according to the high-bit value of the brightness data of the display. Where x is an integer value not greater than m, and each of the x light-emitting unit times is used as the first light-emitting driving unit time of the high bit cell.

In step S107, the light-emitting time determination circuit 20 of the gray-scale generation circuit shown in FIG. 2 is used to select y light-emitting unit times from m light-emitting unit times according to the low-bit value of the brightness data of the display. Where y is an integer value not greater than m, and each of the y light-emitting unit times is used as the second light-emitting driving unit time of the low bit. The aforementioned second light-emitting driving unit time and the first light-emitting driving unit time do not overlap.

In step S109, the driving current distribution circuit 30 (which may be included in the driving circuit of the display) of the grayscale generating circuit shown in FIG. 2 is used to supply the first driving current of the driving signal to the display within each first light-emitting driving unit time , That is, the same fixed current value supplied to the display during each first light-emitting drive unit time.

In step S111, the driving current distribution circuit 30 of the grayscale generating circuit shown in FIG. 2 is used to determine the second driving current according to the low-bit value of the brightness data, where the second driving current is less than the first driving current, and then executing Step S113 or S115.

，其中Is代表第二驅動電流，K代表亮度資料的低位元值，b代表亮度資料的低位元數，I代表固定電流值(等於第一驅動電流值)。 For example, the second driving current is determined according to the low-bit value and the low-bit number of the luminance data, expressed by the equation:

, Where Is represents the second drive current, K represents the low bit value of the brightness data, b represents the low bit number of the brightness data, and I represents the fixed current value (equal to the first drive current value).

In step S113, the driving current distribution circuit 30 of the grayscale generating circuit shown in FIG. 2 is used to determine the second driving current to supply the driving signal within a single second light-emitting driving unit time according to the low-bit value of the brightness data. monitor.

In step S115, the driving current distribution circuit 30 of the grayscale generating circuit shown in FIG. 2 is used to determine the distribution and supply of the second driving current to the display within a plurality of second light-emitting driving unit times according to the low-bit value of the brightness data. .

。發光時間判定電路20從16個(m=16)可發光單位時間TS中，挑選1(y=1)個可發光單位時間TS，例如但不限於決定第4個可發光單位時間TS作為低位元的第二發光驅動單位時間。驅動電流分配電路30在第二發光驅動單位時間內供應電流值為

的第二驅動電流至顯示器。以此方程式可得知第二驅動電流小於電流值為I的第一驅動電流。 For example, as shown in FIG. 3, when the bit value of the brightness data of the display is 000001, the light-emitting time determination circuit 20 is used according to the binary high bit value of the brightness data of the display 0000 (converted to a decimal value of 0), From the 16 (m=16) light-emitting unit time TS, 0 (x=0)/no light-emitting unit time TS is selected as the first light-emitting driving unit time of the upper bit, so the first driving current is not supplied . In addition, the driving current distribution circuit 30 determines the second driving current according to the low-order bit number (=2) of the brightness data of the display and the binary low-order bit value 01 (converted to decimal number 1), which is calculated by the aforementioned equation:

. The light emitting time determination circuit 20 selects 1 (y=1) light emitting unit time TS from 16 (m=16) light emitting unit time TSs, for example, but not limited to determining the fourth light emitting unit time TS as the low bit element The second light-emitting drive unit time. The driving current distribution circuit 30 supplies a current value of

The second driving current to the display. From this equation, it can be known that the second drive current is smaller than the first drive current with a current value of I.

。發光時間判定電路20從16個(m=16)可發光單位時間TS中，挑選1(y=1)個可發光單位時間TS，例如但不限於第1個可發光單位時間TS。驅動電流分 配電路30在第1個可發光單位時間TS內供應電流值為

的第二驅動電流至顯示器。 For another example, as shown in FIG. 3, when the bit value of the brightness data of the display is 000011, the driving current distribution circuit 30 depends on the low bit number (=2) of the brightness data of the display and the binary low bit value 11 (conversion 10 The base is 3) to determine the second drive current, which is calculated by the aforementioned equation:

. The light emitting time determination circuit 20 selects 1 (y=1) light emitting unit time TS from 16 (m=16) light emitting unit time TSs, such as but not limited to the first light emitting unit time TS. The driving current distribution circuit 30 supplies the current value in the first light-emitting unit time TS

The second driving current to the display.

For another example, as shown in FIG. 3, when the bit value of the brightness data of the display is 000100, the light-emitting time determination circuit 20 uses the binary high bit value 0001 (converted to decimal number 1) of the brightness data of the display to change from Among the 16 (m=16) light-emitting unit time TS, select 1 (x=1) light-emitting unit time TS as the first light-emitting drive unit time of the high bit, such as but not limited to the first light-emitting unit time TS , And the driving current distribution circuit 30 supplies a first driving current with a fixed current value of I to the display within the first light-emitting unit time TS.

，在此舉例發光時間判定電路20決定在第6、 11個可發光單位時間TS內各供應電流值為

的電流，實務上，亦可替換為在 單個可發光單位時間TS內供應電流值為

的電流至顯示器。 For another example, as shown in FIG. 3, when the bit value of the brightness data of the display is 001010, the light-emitting time determination circuit 20 uses the binary high bit value 0010 of the brightness data of the display (converted to decimal 2) to change from Among the 16 (m=16) light-emitting unit time TS, select 2 (x=2) light-emitting unit time TS as the first light-emitting driving unit time of the high bit cell, for example, the second and ninth light-emitting unit time TS, The driving current distribution circuit 30 supplies a first driving current whose current value is fixed to I during the second and ninth unit time TS that can emit light. In addition, the driving current distribution circuit 30 determines the second driving current according to the low-order bit number (=2) of the brightness data of the display and the binary low-order bit value 10 (converted to decimal number 2), which is calculated by the aforementioned equation:

In this example, the light emission time determination circuit 20 determines the supply current value in the 6th and 11th unit time TS that can emit light

In practice, it can also be replaced by the supply current value in a single luminous unit time TS

The current to the display.

，在發光時間判定電路20所選擇的第2個可發光單位時間TS內決定供應電流值為

的電流至顯示器。 For another example, as shown in FIG. 3, when the bit value of the brightness data of the display is 111111, the light-emitting time determination circuit 20 uses the binary high bit value 1111 of the brightness data of the display (converted to 15 in decimal) to change from Among the 16 (m=16) light-emitting unit time TSs, select 15 (x=15) light-emitting unit time TSs, such as the 1, 3~16 light-emitting unit time TS as the first light-emitting drive unit time of the high-bit unit , The driving current distribution circuit 30 supplies a first driving current whose current value is fixed to I during the first, third to 16th unit time TS that can emit light. In addition, the driving current distribution circuit 30 determines the second driving current according to the low-bit number of the brightness data of the display and the binary low-bit value 11 (converted to decimal number 3), which is calculated by the aforementioned equation:

, The supply current value is determined in the second light-emitting unit time TS selected by the light-emitting time determination circuit 20

The current to the display.

。當顯示器的亮度資料的灰階值=000011時，顯示器的亮度為

。當顯示器的亮度資料的灰階值=000100時，顯示器的亮度為(1×I×TS)/(16×TS)=4/64。當顯示器的亮度資料的灰階值=001010時，顯示器的亮度為

；當顯示器的亮度資料的灰階值=111111時，顯示器的亮度為

。 As mentioned above, when the grayscale value of the brightness data of the display=000001, the brightness of the display is

. When the grayscale value of the brightness data of the display=000011, the brightness of the display is

. When the grayscale value of the brightness data of the display=000100, the brightness of the display is (1×I×TS)/(16×TS)=4/64. When the grayscale value of the brightness data of the display = 001010, the brightness of the display is

; When the grayscale value of the brightness data of the display=111111, the brightness of the display is

.

That is to say, every time the value of the high bit of 4bits increases by one step, the increased energy is the product of the fixed current value I and the light-emitting unit time TS, and the current per unit time is driven at the fixed current value during the first light-emitting. I, and the increased energy for each increase in the value of the low bit of 2bits is the product of the current value I/(2 ^b ) and the light-emitting unit time TS.

Please refer to FIG. 1, FIG. 2, and FIG. 4, in which FIG. 1 is a flowchart of the steps of a grayscale generation method according to a first embodiment of the present invention; FIG. 2 is a block diagram of a grayscale generation circuit according to the first embodiment of the present invention; 4 is a diagram showing the relationship between driving current and time in the grayscale generation method of the first embodiment of the present invention.

In addition to the above, substituting the high-bit number a of the luminance data into the equation: m=2 ^a to calculate the light-emitting time Tcycle of the frame changing period divided into the number m of light-emitting unit time TS. Alternatively, substitute the high-bit number a and low-bit number b of the brightness data into the equation as follows: m=(2 ^a -1)+(2 ^b -1) to calculate the light-emitting time Tcycle of the frame changing period into The number m of TS per unit time that can emit light.

For example, as shown in FIG. 4, the frame-changing period dividing circuit 10 divides the light-emitting time Tcycle of the frame-changing period into 18 (m=18) light-emitting unit times TS, expressed by the equation: m=(2 ⁴ -1)+(2 ² -1)=18, which is 64/18 times longer than the traditional light-emitting unit time TS0=(Tcycle/(2 ^{6 )).}

。另外，使用如圖2所示的發光時間判定電路20從18個(m=18)可發光單位時間TS中挑選1(y=1)個可發光單位時間TS，例如第1個可發光單位時間TS。在第1個可發光單位時間TS內，驅動電流分配電路30決定供應電流值為

的第二驅動電流至顯示器(如圖1所示的步驟S107、S111、S113)。 As shown in FIG. 4, when the bit value of the brightness data of the display is 000001, the frame change period dividing circuit 10 of the gray scale generation circuit shown in FIG. 2 is used, and the high bit value of the brightness data of the display is 0000( Convert the decimal number to 0), select 0 (x=0)/not select the first light-emitting drive unit time (step S105 shown in FIG. 1). In addition, the driving current distribution circuit 30 using the grayscale generating circuit shown in FIG. 2 determines the second driving current according to the low bit number and the binary low bit value 01 (converting the decimal number to 1), which is calculated by the aforementioned equation:

. In addition, use the light emitting time determination circuit 20 shown in FIG. 2 to select 1 (y=1) light emitting unit time TS from 18 (m=18) light emitting unit time TS, for example, the first light emitting unit time TS TS. In the first light-emitting unit time TS, the drive current distribution circuit 30 determines the supply current value

The second driving current to the display (steps S107, S111, and S113 as shown in FIG. 1).

。另外，發光時間判定電路20從18個(m=18)可發光單位時間TS中挑選2(y=2)個可發光單位時間TS，例如但不限於分配在第3個可發光單位時間TS內供應電流值為

的電流，並在第9個可發光單位時間TS內供應電流值為

的電流(如圖1所示 的步驟S107、S111、S113)。實務上，可替換為在單個可發光單位時間TS即供應電流值為

的電流，或在挑選3個可發光單位時間TS中的每一者各供應 電流值為

的電流。 For another example, as shown in FIG. 4, when the bit value of the brightness data of the display is 000011, the drive current distribution circuit 30 is used according to the high bit value of the brightness data of the display to be 0000 (converted to 0 in decimal), and 0 is selected. (x=0)/the first light-emitting driving unit time is not selected (step S105 shown in FIG. 1). In addition, the driving current distribution circuit 30 determines the second driving current according to the low bit number and the binary low bit value 11 (converted to decimal number 3), which is calculated by the aforementioned equation:

. In addition, the light emitting time determination circuit 20 selects 2 (y=2) light emitting unit time TS from 18 (m=18) light emitting unit time TSs, for example, but not limited to allocating them in the third light emitting unit time TS Supply current value

And the supply current value in the 9th luminous unit time TS is

(Steps S107, S111, S113 shown in Figure 1). In practice, it can be replaced by a single luminous unit time TS that is the supply current value

, Or the supply current value for each of the 3 light-emitting unit times TS is selected

的current.

For another example, as shown in FIG. 4, when the bit value of the brightness data of the display is 000100, the light-emitting time determination circuit 20 uses the binary high bit value 0001 (converted to decimal number 1) of the brightness data of the display to change from 18 Among the (m=18) light-emitting unit time TS, one (x=1) light-emitting unit time TS is selected as the first light-emitting driving unit time of the high bit cell, for example, the second light-emitting unit time TS. The driving current distribution circuit 30 supplies a first driving current with a fixed current value of I to the display during the second unit time TS that can emit light.

，例如但不限於發光時間判定電路20決定在第1、7個可發光單位時間TS內各供應電流值為

的電流，實務上，亦可替換為在單個可發光單位時間TS內供應電流值為

的電流。 For another example, as shown in FIG. 4, when the bit value of the brightness data of the display is 001010, the light-emitting time determination circuit 20 is based on the binary high bit value of the brightness data of the display 0010 (converted to decimal number 2) to change from Among the 18 (m=18) light-emitting unit time TSs, 2 (x=2) light-emitting unit time TSs are selected as the first light-emitting driving unit time of the high bit element, for example, the 4th and 5th light-emitting unit time TS. The driving current distribution circuit 30 supplies a first driving current whose current value is fixed to I during the fourth and fifth light-emitting unit times TS. In addition, the driving current distribution circuit 30 determines the second driving current according to the low-order bit number of the luminance data of the display and the binary low-order bit value 10 (converted to decimal number 2), which is calculated by the aforementioned equation:

For example, but not limited to, the light-emitting time determination circuit 20 determines the value of each supply current in the first and seventh light-emitting unit time TS

In practice, it can also be replaced by the supply current value in a single luminous unit time TS

的current.

，並在發光時間判定電路20所判定的第1、7、3個可發光單位時間TS內決定各供應電流值為

的電流。 For another example, as shown in FIG. 4, when the bit value of the brightness data of the display is 111111, the light-emitting time determination circuit 20 uses the binary high bit value 1111 of the brightness data of the display (converted to 15 in decimal) to change from 18 Among the (m=18) light-emitting unit time TSs, 15 (x=15) light-emitting unit time TSs are selected as the first light-emitting drive unit time of the high-bit element, for example, in the second to sixth, eighth to twelfth, and fourteenth to 18 luminous unit time TS. The driving current distribution circuit 30 supplies a first driving current whose current value is fixed to I during each first light-emitting driving unit time. In addition, the driving current distribution circuit 30 determines the second driving current according to the low-bit number of the brightness data of the display and the binary low-bit value 11 (converted to decimal number 3), which is calculated by the aforementioned equation:

, And determine each supply current value within the first, seventh, and third light-emitting unit time TS determined by the light-emitting time determination circuit 20

的current.

As mentioned above, the energy added for each increase in the value of the high bit of 4bits is the product of the fixed current value I and the light-emitting unit time TS, and the fixed current value is used in the first light-emitting drive unit time of the high bit. I; and when the value of the low bit of 2bits increases by one step, the increase is ^{the product value of the current value I/(2 b} ) and the light-emitting unit time TS.

Please refer to FIGS. 5 to 7, where FIG. 5 is a flowchart of the steps of a grayscale generation method according to a second embodiment of the present invention; FIG. 6 is a block diagram of a grayscale generation circuit according to a second embodiment of the present invention; The relationship between the driving current and the time of the gray-scale generation method of the second embodiment of the invention.

The difference between the second embodiment and the first embodiment is that the first embodiment randomly selects any light-emitting unit time as the first light-emitting driving unit time for high bits or the second light-emitting driving unit time for low bits according to requirements. Differently, in the second embodiment, certain light-emitting unit times are preset to be fixed only as the first light-emitting driving unit time of high bits, and other specific light-emitting unit times are preset to be fixed only as low bits. The second light-emitting drive unit time is specifically described as follows.

As shown in FIG. 5, the grayscale generation method of this embodiment may include steps S201 to S219, and the execution sequence, frequency, and content of the steps may be appropriately omitted or adjusted according to actual needs. These steps S201 to S219 can be performed by, for example, but not limited to, the grayscale generation circuit shown in FIG. 6 to be suitable for displays. The frequency at which the display screen changes is defined as the frame change rate, and the reciprocal of the frame change rate is the frame change period. In fact, there will be some time in the entire frame change period that cannot be used to emit light. The Tcycle shown in Figure 7 represents a frame change. The luminous time within the cycle.

In step S201, the frame change period dividing circuit 10 (which can be included in the display driving circuit) of the gray scale generation circuit shown in FIG. The number of elements or both is used to determine m light-emitting unit time, where n represents the number of bits of the brightness data, and m represents the number of light-emitting unit time.

In step S203, the frame changing period dividing circuit 10 of the gray scale generating circuit shown in FIG. 6 is used to divide the light-emitting time of the frame changing period into m light-emitting unit times TS, where the value of m can adopt the aforementioned related equation It is calculated that, for example, the light-emitting time Tcycle of the frame changing period shown in FIG. 7 is divided into 16 (m=16) light-emitting unit times TS.

In step S205, using the frame changing period dividing circuit 10, g of the fixed m light-emitting unit times are preset to be high-bit light-emitting unit times, where g is an integer value not greater than m.

In step S207, the frame-changing period dividing circuit 10 is used to preset h of the fixed m light-emitting unit times as low-bit light-emitting unit times, where h is an integer value not greater than m. Any of the h light-emitting unit times and any of the g light-emitting unit times do not overlap.

For example, as shown in FIG. 7, taking the 6-bit gray scale of the luminance data into 4 bits high bits and 2 bits low bits as an example, the frame-changing period division circuit 10 is divided according to the number of high bits as (a=4) by default. Specific 15 (g=15) of the total 16 light-emitting unit time TSs out of the total are fixed as high-bit light-emitting unit time TS, calculated by the equation: g=2 ⁴ -1=15, for example, but not It is limited to the preset second to 16th unit time TS that can emit light and is fixed to the high bit unit time TS that can emit light. The remaining light-emitting unit time TS, for example, but not limited to, the first light-emitting unit time TS is fixed to the low-bit light-emitting unit time TS.

As mentioned above, this embodiment exemplifies that the first light-emitting unit time TS is fixed to the low-bit light-emitting unit time TS, but the present invention is not limited to this. In practice, it can replace and preset any of the other 2 to 16 luminous unit time TS. The luminous unit time TS is fixed to the low-bit light-emitting unit time TS, and the first light-emitting unit time TS is fixed to the high position. Luminous unit of yuan Between TS.

For another example, using the frame changing period division circuit 10, according to the number of low bits of the luminance data, the number of light-emitting unit times (that is, the preset h value) fixed to the low bits is preset according to the number of low bits of the luminance data, where the value of h falls between 1 to (2 ^{Within the value range of b} -1), the minimum value of h is 1, and the maximum value of h is (2 ^b -1), where b represents the number of low bits of the brightness data, and h represents the number of light-emitting units of the preset fixed low bits. . It should be understood that the sum of h and g cannot be greater than m. As shown in FIG. 7, taking the 6-bit gray scale of the luminance data into 4 bits high and 2 bits low as an example, the default value of h is 1, which is the minimum value.

In step S209, the light-emitting time determination circuit 20 is used to select x light-emitting unit times from g light-emitting unit times as the first light-emitting drive unit time according to the high bit value of the brightness data, where x is not greater than g Integer value.

In step S211, the light-emitting time determination circuit 20 is used to select y light-emitting unit times from h light-emitting unit times as the second light-emitting drive unit time according to the low-bit value of the brightness data, where y is not greater than h Integer value.

In step S213, the driving current distribution circuit 30 of the grayscale generating circuit shown in FIG. 2 is used to supply the first driving current in each first light-emitting driving unit time.

In step S215, the driving current distribution circuit 30 is used to determine the second driving current according to the low bit value, and then step S217 or step S219 is executed.

In step S217, a complete second driving current is supplied within a single second light-emitting driving unit time.

In step S219, the second driving current is distributed and supplied to the display within a plurality of second light-emitting driving unit times.

，以在預設固定為低位元的第1個可發光單位時間TS供應。 For example, as shown in FIG. 7, when the grayscale value of the luminance data of the display is 000001, the light-emitting time determination circuit 20 is used, and according to the binary high-bit value of the luminance data 0000, 0 (x=0) can be selected. The light-emitting unit time TS is used as the first light-emitting drive unit time, that is, the first light-emitting drive unit time is not selected, and the first low-bit value is determined according to the binary low-bit value 01 (converted to decimal 1) of the brightness data The light-emitting unit time TS is used as the second light-emitting driving unit time. Using the driving current distribution circuit 30, the current value of the second driving current is determined according to the low bit value, and the current value of the second driving current is calculated by the equation:

, It is supplied in the first light-emitting unit time TS which is preset and fixed as the low bit.

，以在預設固定為低位元的第1個可發光單位時間TS供應。 For another example, as shown in FIG. 7, when the grayscale value of the brightness data of the display is 000011, the light-emitting time determination circuit 20 is used, and according to the binary high bit value of the brightness data 0000, select 0 (x=0) light-emitting The unit time TS is used as the first light-emitting drive unit time, that is, the first light-emitting drive unit time is not selected, and the binary low-bit value 11 (converted to decimal 3) of the brightness data is used to determine the first possible low-bit unit The light emission unit time TS is used as the second light emission driving unit time. Using the driving current distribution circuit 30, the current value of the second driving current is determined according to the low bit value, and the current value of the second driving current is calculated by the equation:

, It is supplied in the first light-emitting unit time TS which is preset and fixed as the low bit.

For another example, as shown in FIG. 7, when the grayscale value of the brightness data of the display is 000100, the light-emitting time determination circuit 20 is used, according to the binary high-bit value 0001 of the brightness data (converted to decimal 1), from From the second to 16 light-emitting unit time TS presets fixed to high bits, select one of the light-emitting unit time TS, such as but not limited to the second light-emitting unit time TS, as the first light-emitting driving unit time, The driving current distribution circuit 30 supplies the first driving current with a fixed current value of I during the first light-emitting driving unit time, but the low-bit value is 00 (converted to a decimal value of 0), so it is determined that the second driving current is not supplied.

的第二驅動電流，由於如前述預設僅1個(h=1)可發光單位時間TS(即第1個可發光單位時間TS)作為第二發光驅動單位時間，故在第1個可發光單位時間TS供應電流值為

的完整第二驅動電流。 For another example, as shown in FIG. 7, when the grayscale value of the brightness data of the display is 001010, the light-emitting time determination circuit 20 is used, according to the binary high bit value of the brightness data 0010 (converted to decimal 2), from From the 2nd to 16th luminous unit time TS that are preset to be fixed to high bits, select 2 luminous unit time TS among them, such as but not limited to the second and third luminous unit time TS, as the first light-emitting drive unit time. The driving current distribution circuit 30 is used to supply a first driving current with a fixed current value of I during each first light-emitting driving unit time. In addition, the drive current distribution circuit 30 is used to determine the current value based on the low-order value of 10 (converted to decimal 2) of the brightness data

Since only one (h=1) light-emitting unit time TS (that is, the first light-emitting unit time TS) is preset as the second light-emitting driving unit time as described above, the first light-emitting unit time TS supply current value per unit time

The complete second drive current.

的第二驅動電流，由於如前述預設僅1個(h=1)可發光單位時間TS，例如圖7所示的第1個可發光單位時間TS，作為第二發光驅動單位時間，故在第1個可發光單位時間TS供應電流值為

的完整第二驅動電流。 For another example, as shown in FIG. 7, when the grayscale value of the brightness data of the display is 111111, the light-emitting time determination circuit 20 is used to determine the binary high-bit value 1111 of the brightness data (converted to 15 in decimal), All the second to 16th light-emitting unit time TS that are preset to be fixed to high bits are used as the first light-emitting driving unit time. The driving current distribution circuit 30 is used to supply a first driving current with a fixed current value of I during each first light-emitting driving unit time. In addition, the drive current distribution circuit 30 is used to determine the current value based on the binary low-order value 11 of the brightness data (converted to decimal number 3)

As the second driving current of, since only 1 (h=1) light-emitting unit time TS is preset as described above, for example, the first light-emitting unit time TS shown in FIG. 7 is used as the second light-emitting driving unit time. TS supply current value for the first luminous unit time

The complete second drive current.

To sum up, taking the example shown in Figure 7 as an example, the driving current of the high-bit cell when it emits light during the light-emitting time period adopts a fixed current value I, and the driving current when the low-bit cell emits light during the light-emitting time period is based on the bit The number is determined by the low bit value of 2, and the larger the low bit value, the greater the second drive current.

Please refer to FIG. 8, which is a diagram showing the relationship between the driving current and the time of the gray-scale generation method according to the second embodiment of the present invention.

Different from FIG. 7, as shown in FIG. 8, the frame change period dividing circuit 10 of the gray scale generation circuit shown in FIG. 6 is used to divide the light-emitting time Tcycle of the frame-changing period into 18 light-emitting unit times TS, according to the equation It is expressed as: m=(2 ⁴ -1)+(2 ² -1)=18.

The frame-changing period dividing circuit 10 uses a preset g value according to the number of high bits of the brightness data, expressed as an equation: g=2 ^a -1=2 ⁴ -1=15, for example but not limited to the preset shown in FIG. 8 The 2nd~6th, 8th~12th, 14th~18th luminous unit time is fixed to the high-bit light-emitting unit time TS, where a represents the high-bit number of the brightness data, and g represents the default fixed high-bit The number of light-emitting unit time TS.

In addition, the frame-changing period dividing circuit 10 uses a preset value of h according to the number of low bits of the luminance data, expressed as an equation: h=(2 ^b -1)=(2 ² -1)=3, for example, as shown in FIG. 8 The first, seventh, and thirteenth light-emitting unit times are preset to be the low-bit light-emitting unit time TS, where b represents the low-bit number of the luminance data, and h represents the number of light-emitting unit time TS that is preset and fixed to the low bit.

The following is an example of how to determine how many driving currents are supplied in which light-emitting driving unit time when the grayscale values of the brightness data of the display are different.

，以在第1個可發光單位時間TS供應電流值為

的第二驅動電流至顯示器。 For example, as shown in FIG. 8, when the grayscale value of the brightness data of the display is 000001, the light-emitting time determination circuit 20 is used to select 0 (x=0) according to the binary high-bit value of the brightness data 0000. The light-emitting unit time TS is used as the first light-emitting driving unit time, that is, the first light-emitting driving unit time is not selected. In addition, the luminous time determination circuit 20 is used to determine the low-order value 01 (converted to decimal number 1) of the brightness data from the first, seventh, and thirteenth light-emitting unit time TS that is fixed to the low-order bit by default. For example, the first light-emitting unit time TS is selected as the second light-emitting driving unit time. The driving current distribution circuit 30 determines the current value of the second driving current according to the low bit value, which is calculated by the equation:

, Taking the supply current value of TS in the first light-emitting unit time

The second driving current to the display.

，分別在發光時間判定電路20所決定的所有預設固定為低位元的第1、7、13個可發光單位時間TS中，例如但不限於平均分配供應電流值為

的第二驅動電流至顯示器，即在第1、7、13個可發光單位時間TS各供應電流值為

的驅動電流至顯示器。 For another example, as shown in FIG. 8, when the bit value of the brightness data of the display is 000011, the drive current distribution circuit 30 depends on the low bit number (=2) of the brightness data of the display and the binary low bit value 11 (conversion 10 The base is 3) to determine the second drive current, which is calculated by the aforementioned equation:

, Respectively, in all the first, seventh, and thirteenth light-emitting unit times TS determined by the light-emitting time determination circuit 20 and fixed to the low bits, for example, but not limited to the evenly distributed supply current value

The second driving current to the display, that is, the supply current value of TS is

The drive current to the display.

For another example, as shown in FIG. 8, when the bit value of the brightness data of the display is 000100, the light-emitting time determination circuit 20 uses the binary high-bit value 0001 (converted to decimal to 1) of the brightness data of the display from the preset value. Set the 2nd~6th, 8th~12th, 14th~18th light emitting unit time TS fixed as high bits, select 1 (x=1) light emitting unit time TS as the first light emitting drive for high bits The unit time, such as, but not limited to, the fourth light-emitting unit time TS. The driving current distribution circuit 30 supplies the first driving current with a fixed current value of I to the display in the fourth unit time TS that can emit light.

，在此舉例在第1、7個可發光單位時間TS內各供應電流值為

的電流，實務上，亦可替換為在單個可發光單位時間TS內供應電流值為

的電流至顯示器。 For another example, as shown in FIG. 8, when the bit value of the brightness data of the display is 001010, the light-emitting time determination circuit 20 uses the binary high bit value 0010 of the brightness data of the display (converted to the decimal number 2) to change from The 2nd~6th, 8th~12th, 14th~18th luminous unit time TS that is fixed to the high bit by default, select 2 (x=2) luminous unit time TS as the first light emitting of the high bit Drive unit time, such as the 3rd and 11th unit time TS that can emit light. The driving current distribution circuit 30 supplies a first driving current whose current value is fixed to I during the third and eleventh light-emitting unit time TS. In addition, the light-emitting time determination circuit 20 determines the number of low-order bits of the brightness data of the display and the low-order value of 10 (converted to 2 in decimal). In the unit time TS, two light-emitting unit time TS are selected, for example, the first and seventh light-emitting unit time TS shown in FIG. 8. The driving current distribution circuit 30 determines the second driving current according to the low-bit value of the brightness data of the display, which is calculated by the aforementioned equation:

, In this example, the value of each supply current in the first and seventh light-emitting unit time TS is

In practice, it can also be replaced by the supply current value in a single luminous unit time TS

The current to the display.

，分別在發光時間判定電路20所決定的預設固定為低位元的第1、7、13個可發光單位時間TS中，例如但不限於平均分配供應電流值為

的第二驅動電流至顯示器，即在第1、7、13個可發光單位時間TS各供應電流值為

的驅動電流至顯示器。 For another example, as shown in FIG. 8, when the bit value of the brightness data of the display is 111111, the light-emitting time determination circuit 20 selects 1111 according to the binary high bit value of the brightness data of the display (converted to 15 in decimal). All the 2nd~6th, 8th~12th, 14th~18th light-emitting unit time TS (x=15) that are preset to be fixed to high bits are used as the first light-emitting drive unit time. The driving current distribution circuit 30 supplies a first driving current whose current value is fixed to I during each first light-emitting driving unit time. In addition, the driving current distribution circuit 30 determines the second driving current according to the low-bit number of the brightness data of the display and the binary low-bit value 11 (converted to decimal number 3), which is calculated by the aforementioned equation:

, Respectively in the first, seventh, and thirteenth light-emitting unit time TS determined by the light-emitting time determination circuit 20 and fixed to the low bit, for example, but not limited to the evenly distributed supply current value

The second driving current to the display, that is, the supply current value of TS is

The drive current to the display.

Please refer to FIG. 9, which is a diagram showing the relationship between the driving current and time of the driving signal segment scanning of the grayscale generating circuit of the third embodiment of the present invention.

The scan control circuit (not shown) of the display can be connected to the display and the drive current distribution circuit 30. The scan control circuit can divide the first scan drive signal in the drive signal (including the first drive current and the second drive current) into a plurality of first scan segments, such as but not limited to two first scan segments as shown in FIG. 9 The first segment Sc11, the second segment Sc12 of the first scan, and the second scan driving signal in this driving signal are divided into a plurality of second scan segments, such as but not limited to two second scan segments as shown in FIG. 9 First paragraph Sc21, the second section Sc22 of the second scan.

As shown in Figure 9, the scan control circuit scans the first segment Sc11 of the first scan, then waits for a ghost removal time Toff, scans the first segment Sc21 of the second scan, and then waits for a ghost removal time Toff, Scan the second segment Sc12 of the first scan, and then wait for a ghost removal time Toff, then scan the second segment Sc22 of the second scan to perform alternate scanning. In this embodiment, the brightness data of the first scan is 111101 and the brightness data of the second scan is 010011 as an example, but the present invention is not limited thereto.

As mentioned above, in the scanning application, the light-emitting unit time of each scan is divided into several segments, and the different segments of each scan are separated by a certain segment of other scans. Furthermore, the ghost image elimination time Toff can be inserted between two adjacent sections with different scans, so as to solve the ghost image problem.

One of the beneficial effects of the present invention is that the gray level generating circuit and method provided by the present invention can increase the number of gray levels of the display without greatly shortening the length of the unit time that can emit light, thereby improving the display effect of the display.

The content disclosed above is only the preferred and feasible embodiments of the present invention, and does not limit the scope of the patent application of the present invention. Therefore, all equivalent technical changes made using the description and schematic content of the present invention are included in the application of the present invention. Within the scope of the patent.

S101~S115: steps

Claims (16)

A gray-scale generation method is suitable for a display. The frequency at which the display screen changes is defined as a frame-changing rate, and the inverse of the frame-changing rate is a frame-changing period. The gray-scale generation method includes the following steps: The number of high bits, the number of low bits, or both of the brightness data is used to determine the light-emitting time of the frame change period into m light-emitting unit times, where m is an integer value, representing the number of light-emitting unit times; The high bit value of the brightness data is to select x light-emitting unit times from the m light-emitting unit times, where x is an integer value not greater than m, and each of the x light-emitting unit times is regarded as a first Light-emitting drive unit time; according to the low-bit value of the luminance data, select y light-emitting unit times from the m light-emitting unit times, where y is an integer value not greater than m, and among the y light-emitting unit times Each of is used as a second light-emitting driving unit time, the second light-emitting driving unit time does not overlap the first light-emitting driving unit time; a first driving current that supplies a driving signal in each of the first light-emitting driving unit times To the display; and determine a second driving current of the driving signal according to the low-bit value of the luminance data, wherein the second driving current is supplied in a single second light-emitting driving unit time, or in the plurality of first The two light-emitting drives are distributed and supplied per unit time, wherein the second drive current is less than the first drive current. The grayscale generation method described in claim 1 further includes the following steps: determining the minimum value of m according to the number of high bits of the brightness data, expressed by the equation: m=2 ^a , where a represents the value of the brightness data High bit number. The grayscale generation method described in claim 1 further includes the following steps: determine the maximum value of m according to the number of high bits and the number of low bits of the brightness data, expressed by the equation: m=(2 ^a -1) +(2 ^b -1), where a represents the number of high bits of the brightness data, and b represents the number of low bits of the brightness data. The gray-scale generation method as described in claim 1 further includes the following steps: determining the second driving current according to the low-bit value and low-bit number of the luminance data, expressed as an equation:

, Where Is represents the second drive current, K represents the low bit value of the brightness data, b represents the low bit number of the brightness data, I represents a fixed current, and the value of the first drive current is equal to the value of the fixed current. The gray-scale generation method according to claim 1, further comprising the following steps: preset fixing g of the m light-emitting unit times as high-bit light-emitting unit times and fixing h as low-bit light-emitting units Time, where g and h are integer values not greater than m, and any of the g light-emitting unit times does not overlap with any of the h light-emitting unit times; according to the high-bit value of the brightness data, To select x light-emitting unit times from g light-emitting unit times, where x is an integer value not greater than g; and according to the low-bit value of the brightness data, to select y light-emitting unit times from h light-emitting unit times Light-emitting unit time, where y is an integer value not greater than h. The grayscale generation method described in claim 5 further includes the following steps: according to the high-bit number of the brightness data, a preset g value is expressed as an equation: g=2 ^a -1, where a represents the brightness data The high number of bits. The gray-scale generation method of claim 5 further includes the following steps: preset h value according to the low-bit number of the brightness data, where the h value falls within the value range of ^{1 to (2 b -1),} The minimum value of h is 1, and the maximum value of h is (2 ^b -1), where b represents the number of low bits of the luminance data. The grayscale generation method according to claim 1, further comprising the following steps: dividing a first scan driving signal in the driving signal into a plurality of first scan segments; Divide a second scan driving signal in the driving signal into a plurality of second scan segments; after scanning one of the first scan segments of the plurality of first scan segments, wait for a ghost image elimination time; and scan the plurality of scan segments. After one of the second scan segments of the second scan segments, wait for the ghost image elimination time, and then return to the previous step to scan the other first scan segment of the plurality of first scan segments until After scanning all the plurality of first scan segments and the plurality of second scan segments. A gray-scale generation circuit is suitable for a display. The frequency at which the display screen changes is defined as a frame-changing rate. The reciprocal of the frame-changing rate is a frame-changing period. The gray-scale generating circuit includes: a frame-changing period dividing circuit, The configuration is based on the high-bit number, low-bit number or both of a brightness data to determine the light-emitting time of the frame change period into m light-emitting unit times, where m is an integer value, which represents the light-emitting unit time Quantity; a light-emitting time determination circuit, connected to the frame changing period division circuit and the display, configured to select x light-emitting unit times from the m light-emitting unit times according to the high-bit value of the brightness data of the display , According to the low-bit value of the brightness data, to select y light-emitting unit times from the m light-emitting unit times, where x and y are integer values not greater than m, and each of the x light-emitting unit times As a first light-emitting driving unit time, each of the y light-emitting unit times is used as a second light-emitting driving unit time, and the second light-emitting driving unit time does not overlap with the first light-emitting driving unit time; and a driving current The distribution circuit is connected to the light-emitting time determination circuit and the display, supplies a first driving current of a driving signal to the display within each first light-emitting driving unit time, and is configured to determine according to the low-bit value of the brightness data A second driving current of the driving signal is then determined in The second driving current for supplying the driving signal within a single second light-emitting driving unit time, or the second driving current is distributed and supplied to the display within a plurality of second light-emitting driving unit times, wherein the second driving current Less than the first drive current. The gray-scale generation circuit according to claim 9, wherein the frame-changing period division circuit determines the minimum value of m according to the number of high bits of the brightness data, expressed by the equation: m=2 ^a , where a represents the brightness The high number of bits of the data. The gray-scale generation circuit according to claim 9, wherein the frame-changing period dividing circuit determines the maximum value of m according to the number of high bits and the number of low bits of the luminance data, expressed by the equation: m=(2 ^a- 1)+(2 ^b -1), where a represents the number of high bits of the brightness data, and b represents the number of low bits of the brightness data. The gray-scale generation circuit according to claim 9, wherein the drive current distribution circuit is configured to determine the second drive current according to the low-bit value and the low-bit number of the luminance data, expressed by the equation:

, Where Is represents the second drive current, K represents the low bit value of the brightness data, b represents the low bit number of the brightness data, I represents a fixed current, and the value of the first drive current is equal to the value of the fixed current . The gray-scale generation circuit according to claim 9, wherein the frame changing period dividing circuit is configured to preset g high-bit light-emitting unit times among the m light-emitting unit times and fix h light-emitting unit times as low bits. Light-emitting unit time, where g and h are integer values not greater than m, and any of the g light-emitting unit times does not overlap with any of the h light-emitting unit times; wherein the light-emitting time determination circuit is based on The high-bit value of the brightness data is used to select x light-emitting unit times from g light-emitting unit times, and according to the low-bit value of the brightness data, y light-emitting units are selected from h light-emitting unit times Time, where x is an integer value not greater than g, and y is an integer value not greater than h. The gray-scale generation circuit according to claim 13, wherein the frame-changing period division circuit uses a preset g value according to the number of high bits of the luminance data, expressed by an equation: g=2 ^a -1, where a represents the The number of high bits of the brightness data. The gray-scale generation circuit according to claim 13, wherein the frame-changing period division circuit presets a value of h according to the number of low bits of the luminance data, wherein the value of h falls within a value range of ^{1 to (2 b -1)} Within, the minimum value of h is 1, and the maximum value of h is (2 ^b -1), where b represents the number of low bits of the luminance data. The gray scale generation circuit according to claim 9, wherein a scan control circuit of the display is connected to the display and the drive current distribution circuit, a first scan drive signal in the drive signal is divided into a plurality of first scan segments, the A second scan driving signal in the driving signal is divided into a plurality of second scan segments, and the scan control circuit is configured to scan one of the plurality of first scan segments, and then wait for a ghost elimination time , Scan one of the second scan segments of the plurality of second scan segments, and then after waiting for the ghost image elimination time, scan the other first scan segment of the plurality of first scan segments, alternately in this way Scan all the plurality of first scan segments and the plurality of second scan segments.

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