Backlight module, driving method, and display apparatus

Abstract

A backlight module, a driving method, and a display apparatus. The backlight module comprises a plurality of light-emitting units (E1, ..., E6), wherein the plurality of light-emitting units (E1, ..., E6) are sequentially turned on; and the plurality of light-emitting units (E1, ..., E6) emit light of the same color. The plurality of light-emitting units (E1, ..., E6) comprised in the backlight module are sequentially turned on, thereby avoiding backlight flickering caused by the simultaneous turning-on and turning-off of the plurality of light-emitting units (E1, ..., E6), and thus improving the viewing experience.

Description

Backlight module, driving method and display device Technical Field

[0001] This disclosure relates to the field of display technology, and in particular to a backlight module, driving method and display device. Background Technology

[0002] Display devices typically use PWM (Pulse Width Modulation) signals to dim the backlight module. To maintain a specific brightness level, pulsed current causes screen flicker. This flicker is faster at high brightness and slower at low brightness, and is highly dependent on the material of the light-emitting units in the backlight module. Slower flicker speeds can cause eye strain for users. In related technologies, multiple light-emitting units in the backlight module are simultaneously turned on and off using PWM signals, making the backlight flicker more noticeable.

[0003] Summary of the Invention

[0004] In one aspect, embodiments of this disclosure provide a backlight module including a plurality of light-emitting units;

[0005] The multiple light-emitting units are lit up sequentially;

[0006] The multiple light-emitting units emit the same color.

[0007] In at least one embodiment of this disclosure, the duration for which the light-emitting unit is continuously turned on is te; the backlight module includes N light-emitting units; N is an integer greater than 1; te is the light-emitting time;

[0008] The lighting time of the m-th light-emitting unit and the lighting time of the (m+1)-th light-emitting unit are separated by a×te; where a is a positive number, greater than 0 and less than 1, m is a positive integer, and m+1 is less than or equal to N.

[0009] In at least one embodiment of this disclosure, the b-th lighting time of the Nth light-emitting unit is set before the b+1-th lighting time of the first light-emitting unit;

[0010] The interval between the b-th lighting time of the Nth light-emitting unit and the b+1-th lighting time of the first light-emitting unit is c×te; c is a positive number, greater than 0 and less than 1.

[0011] The backlight module described in at least one embodiment of this disclosure further includes a driver integrated circuit, a timing controller, a switching circuit, and a delay circuit;

[0012] The driving integrated circuit includes N driving current output terminals, the switching circuit includes N switching sub-circuits, the delay circuit includes N delay sub-circuits, and the timing controller includes a PWM signal terminal.

[0013] The driving integrated circuit includes an nth driving current output terminal that is electrically connected to the first terminal of the nth switch sub-circuit.

[0014] The input terminal of the nth delay sub-circuit is electrically connected to the PWM signal terminal, the output terminal of the nth delay sub-circuit is electrically connected to the control terminal of the nth switch sub-circuit, and the second terminal of the nth switch sub-circuit is electrically connected to the nth backlight current supply terminal.

[0015] The nth light-emitting unit is electrically connected to the nth backlight current providing terminal;

[0016] n is a positive integer, and n is less than or equal to N.

[0017] In at least one embodiment of this disclosure, the nth delay sub-circuit includes an nth resistor and an nth capacitor;

[0018] The first end of the nth resistor is electrically connected to the PWM signal terminal, and the second end of the nth resistor is electrically connected to the control terminal of the nth switch sub-circuit.

[0019] The first terminal of the nth capacitor is electrically connected to the second terminal of the nth resistor, and the second terminal of the nth capacitor is electrically connected to the DC voltage terminal.

[0020] In at least one embodiment of this disclosure, the nth switch sub-circuit includes an nth switch transistor;

[0021] The gate of the nth switching transistor is electrically connected to the control terminal of the nth switching sub-circuit, the first terminal of the nth switching transistor is electrically connected to the first terminal of the nth switching circuit, and the second terminal of the nth switching transistor is electrically connected to the second terminal of the nth switching circuit.

[0022] In at least one embodiment of this disclosure, the light-emitting unit includes a plurality of LEDs connected in series.

[0023] The backlight module described in at least one embodiment of this disclosure further includes a backlight adjustment unit;

[0024] The backlight adjustment unit includes a control signal supply circuit and a switching circuit; the switching circuit includes N switching sub-circuits; N is a positive integer; n is a positive integer less than or equal to N;

[0025] The control signal providing circuit is electrically connected to the control terminal of the plurality of switch sub-circuits and is used to provide corresponding switch control signals to the control terminal of the switch sub-circuit.

[0026] The nth switch sub-circuit is electrically connected to the nth backlight current providing terminal and the nth light-emitting unit, respectively, and is used to write the nth backlight current provided by the nth backlight current providing terminal into the nth light-emitting unit during the nth light-emitting stage.

[0027] In at least one embodiment of this disclosure, the control signal providing circuit includes N delay sub-circuits;

[0028] The nth delay sub-circuit is electrically connected to the control terminal of the PWM signal terminal and the control terminal of the nth switch sub-circuit, respectively, and is used to control the PWM signal provided by the PWM signal terminal to be delayed by the nth delay time to obtain the nth switch control signal, and to provide the nth switch control signal to the control terminal of the nth switch sub-circuit.

[0029] In a second aspect, embodiments of this disclosure provide a driving method applied to the aforementioned backlight module; the driving method includes:

[0030] Control multiple light-emitting units to light up sequentially.

[0031] In at least one embodiment of this disclosure, the duration for which the light-emitting unit is continuously turned on is te; the backlight module includes N light-emitting units; N is an integer greater than 1; te is the light-emitting time; the driving method includes:

[0032] Control the lighting time of the m-th light-emitting unit and the lighting time of the (m+1)-th light-emitting unit, with an interval of a×te;

[0033] Where a is a positive number, a is greater than 0 and less than 1, m is a positive integer, and m+1 is less than or equal to N.

[0034] The driving method described in at least one embodiment of this disclosure includes:

[0035] The lighting time of the bth light-emitting unit of the Nth light-emitting unit is set before the lighting time of the (b+1)th light-emitting unit of the first light-emitting unit.

[0036] The interval between the b-th lighting time of the Nth light-emitting unit and the b+1-th lighting time of the first light-emitting unit is controlled to be c×te;

[0037] c is a positive number, greater than 0 and less than 1.

[0038] In at least one embodiment of this disclosure, the backlight module further includes a backlight adjustment unit; the backlight adjustment unit includes a control signal providing circuit and a switching circuit; the switching circuit includes N switching sub-circuits; N is a positive integer; n is a positive integer less than or equal to N; the light emission period of the backlight module includes N light emission stages; the driving method includes:

[0039] The control signal providing circuit provides the corresponding switching control signal to the control terminal of the switching sub-circuit;

[0040] The nth switch sub-circuit writes the nth backlight current into the nth light-emitting unit during the nth light-emitting stage;

[0041] The start times of the N luminescence stages are different.

[0042] In at least one embodiment of this disclosure, the control signal providing circuit includes N delay sub-circuits;

[0043] The step of the control signal providing circuit providing the corresponding switch control signal to the control terminal of the switch sub-circuit includes:

[0044] The nth delay sub-circuit controls the PWM signal to be delayed by the nth delay time to obtain the nth switch control signal, and provides the nth switch control signal to the control terminal of the nth switch sub-circuit.

[0045] In at least one embodiment of this disclosure, the (n+1)th delay time is greater than the nth delay time.

[0046] In a third aspect, embodiments of this disclosure provide a display device, including the backlight module described above, and a liquid crystal display panel;

[0047] The liquid crystal display panel is located on the light-emitting side of the module. Attached Figure Description

[0048] Figure 1 is a timing diagram of a backlight module according to at least one embodiment of the present disclosure;

[0049] Figure 2 is a structural diagram of a backlight module according to at least one embodiment of the present disclosure;

[0050] Figure 3 is a circuit diagram of at least one embodiment of the first delay sub-circuit;

[0051] Figure 4 is a circuit diagram of at least one embodiment of the second delay sub-circuit;

[0052] Figure 5 is a circuit diagram of at least one embodiment of the third delay sub-circuit;

[0053] Figure 6 is a circuit diagram of at least one embodiment of the fourth delay sub-circuit;

[0054] Figure 7 is a circuit diagram of at least one embodiment of the fifth delay sub-circuit;

[0055] Figure 8 is a circuit diagram of at least one embodiment of the sixth delay sub-circuit;

[0056] Figure 9 is a timing diagram of a backlight module according to at least one embodiment of the present disclosure;

[0057] Figure 10 is the circuit diagram of the delay sub-circuit;

[0058] Figure 11 is a schematic diagram of the charging state of the delay sub-circuit shown in Figure 10;

[0059] Figure 12 is a structural diagram of a backlight module according to at least one embodiment of the present disclosure;

[0060] Figure 13 is a structural diagram of a backlight module according to at least one embodiment of the present disclosure;

[0061] Figure 14 is a structural diagram of a backlight module according to at least one embodiment of the present disclosure. Detailed Implementation

[0062] The technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. Based on the embodiments of this disclosure, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this disclosure.

[0063] In all embodiments of this disclosure, the transistors used can be thin-film transistors, field-effect transistors, or other devices with similar characteristics. In the embodiments of this disclosure, to distinguish the two terminals of the transistor other than the gate, one terminal is referred to as the first terminal and the other as the second terminal.

[0064] In actual operation, when the transistor is a thin-film transistor or a field-effect transistor, the first electrode can be the drain and the second electrode can be the source; or, the first electrode can be the source and the second electrode can be the drain.

[0065] The backlight module described in this embodiment includes multiple light-emitting units;

[0066] The multiple light-emitting units are lit up sequentially;

[0067] The multiple light-emitting units emit the same color.

[0068] In this embodiment of the disclosure, the backlight module includes multiple light-emitting units that are lit sequentially, avoiding the simultaneous turning on and off of the multiple light-emitting units, which can reduce backlight flicker and improve the viewing experience.

[0069] In at least one embodiment of this disclosure, the light emitted by the light-emitting unit can be blue light or white light;

[0070] When the light-emitting unit emits blue light, the backlight module includes an optical film located between the liquid crystal display panel and the light-emitting unit. The optical film includes a color conversion film for converting the blue light emitted by the backlight module into white light.

[0071] In at least one embodiment of this disclosure, the light-emitting unit may include a plurality of LEDs (light-emitting diodes); the plurality of LEDs may be connected in series or in parallel, or the plurality of LEDs may be connected in series to form a string of lights, and then the strings of lights may be connected in parallel.

[0072] The plurality of light-emitting units can be arranged sequentially along the row direction; or, the plurality of light-emitting units can be arranged sequentially along the column direction; or, the plurality of light-emitting units can be arranged in an array.

[0073] In at least one embodiment of this disclosure, the duration for which the light-emitting unit is continuously turned on is te; the backlight module includes N light-emitting units; N is an integer greater than 1; te is the light-emitting time;

[0074] The lighting time of the m-th light-emitting unit and the lighting time of the (m+1)-th light-emitting unit are separated by a×te; where a is a positive number, greater than 0 and less than 1, m is a positive integer, and m+1 is less than or equal to N.

[0075] In at least one embodiment of this disclosure, the lighting time of the light-emitting unit may refer to the moment when the light-emitting unit begins to emit light.

[0076] In Figure 1, the terminal labeled IFB1 is the first backlight current providing terminal, the terminal labeled IFB2 is the second backlight current providing terminal, the terminal labeled IFB3 is the third backlight current providing terminal, the terminal labeled IFB4 is the fourth backlight current providing terminal, the terminal labeled IFB5 is the fifth backlight current providing terminal, and the terminal labeled IFB6 is the sixth backlight current providing terminal.

[0077] As shown in Figure 1, the duration for which the first light-emitting unit is continuously turned on once is the light-emitting time te;

[0078] As shown in Figure 1, the duration te of the first light-emitting unit being continuously turned on once can be the pulse width of the high-level pulse of the first backlight circuit provided by the first backlight current providing terminal.

[0079] The time interval between the lighting time of the second light-emitting unit and the lighting time of the first light-emitting unit is tj1, where tj1 is the first interval time, tj1 is a1×te, a1 is a positive number, a1 is greater than 0 and less than 1;

[0080] The interval between the lighting time of the third light-emitting unit and the lighting time of the second light-emitting unit is tj2, where tj2 is the second interval time, tj2 is a2×te, a2 is a positive number, a2 is greater than 0 and less than 1;

[0081] The interval between the lighting time of the fourth light-emitting unit and the lighting time of the third light-emitting unit is tj3, where tj3 is the third interval time, tj3 is a3×te, a3 is a positive number, a3 is greater than 0 and less than 1;

[0082] The interval between the lighting time of the fifth light-emitting unit and the lighting time of the fourth light-emitting unit is tj4, where tj4 is the fourth interval time, tj4 is a4×te, a4 is a positive number, a4 is greater than 0 and less than 1;

[0083] The interval between the lighting time of the sixth light-emitting unit and the lighting time of the fifth light-emitting unit is tj5, where tj5 is the fifth interval time, tj5 is a5×te, a5 is a positive number, a5 is greater than 0 and less than 1.

[0084] In at least one embodiment of this disclosure, the b-th lighting time of the Nth light-emitting unit is set before the b+1-th lighting time of the first light-emitting unit;

[0085] The interval between the b-th lighting time of the Nth light-emitting unit and the b+1-th lighting time of the first light-emitting unit is c×te; c is a positive number, greater than 0 and less than 1.

[0086] As shown in Figure 1, N equals 6, and the b-th lighting time of the Nth light-emitting unit is set before the b+1-th lighting time of the first light-emitting unit;

[0087] The interval between the second lighting moment of the sixth light-emitting unit and the third lighting moment of the first light-emitting unit is tj6, where tj6 is the sixth interval time, tj6 is c×te, c is a positive number, and c is greater than 0 and less than 1.

[0088] In at least one embodiment shown in Figure 1, the period of the backlight current provided by each backlight current providing terminal is T, and tj1, tj2, tj3, tj4, tj5 and tj6 can all be equal to T / 6.

[0089] By using the light emission timing shown in Figure 1, under the premise of controlling the time-sharing of N light emission units, the light emission time of adjacent light emission units can overlap, thereby reducing the time required to light up all the light emission units included in the backlight module and controlling the backlight module to light up quickly.

[0090] As shown in Figure 2, the backlight module described in at least one embodiment of this disclosure further includes a driver integrated circuit DI, a timing controller Tc, a switching circuit 21, and a delay circuit 22; N equals 6;

[0091] The driver integrated circuit DI includes a first drive current output terminal CH1, a second drive current output terminal CH2, a third drive current output terminal CH3, a fourth drive current output terminal CH4, a fifth drive current output terminal CH5, and a sixth drive current output terminal CH6; the switching circuit 21 includes a first switching sub-circuit K1, a second switching sub-circuit K2, a third switching sub-circuit K3, a fourth switching sub-circuit K4, a fifth switching sub-circuit K5, and a sixth switching sub-circuit K6; the delay circuit 22 includes a first delay sub-circuit Y1, a second delay sub-circuit Y2, a third delay sub-circuit Y3, a fourth delay sub-circuit Y4, a fifth delay sub-circuit Y5, and a sixth delay sub-circuit Y6; the timing controller Tc includes a PWM signal terminal PD;

[0092] The first drive current output terminal CH1 is electrically connected to the first terminal of the first switch sub-circuit K1; the input terminal of the first delay sub-circuit Y1 is electrically connected to the PWM signal terminal PD; the output terminal of the first delay sub-circuit Y1 is electrically connected to the control terminal of the first switch sub-circuit K1; the second terminal of the first switch sub-circuit K1 is electrically connected to the first backlight current supply terminal IFB1; and the first backlight current supply terminal IFB1 is electrically connected to the first light-emitting unit E1.

[0093] The second drive current output terminal CH2 is electrically connected to the first terminal of the second switch sub-circuit K2; the input terminal of the second delay sub-circuit Y2 is electrically connected to the PWM signal terminal PD; the output terminal of the second delay sub-circuit Y2 is electrically connected to the control terminal of the second switch sub-circuit K2; the second terminal of the second switch sub-circuit K2 is electrically connected to the second backlight current providing terminal IFB2; the second backlight current providing terminal IFB2 is electrically connected to the second light-emitting unit E2.

[0094] The third drive current output terminal CH3 is electrically connected to the first terminal of the third switch sub-circuit K3; the input terminal of the third delay sub-circuit Y3 is electrically connected to the PWM signal terminal PD; the output terminal of the third delay sub-circuit Y3 is electrically connected to the control terminal of the third switch sub-circuit K3; the second terminal of the third switch sub-circuit K3 is electrically connected to the third backlight current supply terminal IFB3; and the third backlight current supply terminal IFB3 is electrically connected to the third light-emitting unit E3.

[0095] The fourth drive current output terminal CH4 is electrically connected to the first terminal of the first switch sub-circuit K1; the input terminal of the fourth delay sub-circuit Y4 is electrically connected to the PWM signal terminal PD; the output terminal of the fourth delay sub-circuit Y4 is electrically connected to the control terminal of the fourth switch sub-circuit K4; the second terminal of the fourth switch sub-circuit K4 is electrically connected to the fourth backlight current providing terminal IFB4; the fourth backlight current providing terminal IFB4 is electrically connected to the fourth light-emitting unit E4.

[0096] The fifth drive current output terminal CH5 is electrically connected to the first terminal of the fifth switch sub-circuit K5; the input terminal of the fifth delay sub-circuit Y5 is electrically connected to the PWM signal terminal PD; the output terminal of the fifth delay sub-circuit Y5 is electrically connected to the control terminal of the fifth switch sub-circuit K5; the second terminal of the fifth switch sub-circuit K5 is electrically connected to the fifth backlight current supply terminal IFB5; the fifth backlight current supply terminal IFB5 is electrically connected to the fifth light-emitting unit E5.

[0097] The sixth drive current output terminal CH6 is electrically connected to the first terminal of the sixth switch sub-circuit K6; the input terminal of the sixth delay sub-circuit Y6 is electrically connected to the PWM signal terminal PD; the output terminal of the sixth delay sub-circuit Y6 is electrically connected to the control terminal of the sixth switch sub-circuit K6; the second terminal of the sixth switch sub-circuit K6 is electrically connected to the sixth backlight current supply terminal IFB6; and the sixth backlight current supply terminal IFB6 is electrically connected to the sixth light-emitting unit E6.

[0098] Based on at least one embodiment shown in Figure 2, at least one embodiment of the backlight module may further include a user interface;

[0099] Configure one GPIO (General-purpose input / output) pin of the timing controller Tc to output a stable high and low level PWM signal. The timing and duty cycle of the PWM signal are set internally by the timing controller Tc to be consistent with the timing and duty cycle of the input PWM signal of the user interface.

[0100] Optionally, the nth delay sub-circuit includes an nth resistor and an nth capacitor;

[0101] The first end of the nth resistor is electrically connected to the PWM signal terminal, and the second end of the nth resistor is electrically connected to the control terminal of the nth switch sub-circuit.

[0102] The first terminal of the nth capacitor is electrically connected to the second terminal of the nth resistor, and the second terminal of the nth capacitor is electrically connected to the DC voltage terminal.

[0103] Optionally, the nth switch sub-circuit includes the nth switch transistor;

[0104] The gate of the nth switching transistor is electrically connected to the control terminal of the nth switching sub-circuit, the first terminal of the nth switching transistor is electrically connected to the first terminal of the nth switching circuit, and the second terminal of the nth switching transistor is electrically connected to the second terminal of the nth switching circuit.

[0105] As shown in Figure 3, the first delay sub-circuit includes a first resistor R1 and a first capacitor C1; the first switching sub-circuit includes a first switching transistor U11.

[0106] The first terminal of R1 is electrically connected to the PWM signal terminal PD, and the second terminal of R1 is electrically connected to the gate of U11; the first terminal of C1 is electrically connected to the second terminal of R1, and the second terminal of C1 is electrically connected to the ground terminal GND.

[0107] The source of U11 is electrically connected to the first drive current output terminal CH1, and the drain of U11 is electrically connected to the first backlight current supply terminal IFB1.

[0108] U11 is an n-type transistor.

[0109] As shown in Figure 4, the second delay sub-circuit includes a second resistor R2 and a second capacitor C2; the second switching sub-circuit includes a second switching transistor U12.

[0110] The first terminal of R2 is electrically connected to the PWM signal terminal PD, and the second terminal of R2 is electrically connected to the gate of U12; the first terminal of C2 is electrically connected to the second terminal of R2, and the second terminal of C2 is electrically connected to the ground terminal GND.

[0111] The source of U12 is electrically connected to the second drive current output terminal CH2, and the drain of U12 is electrically connected to the second backlight current supply terminal IFB2.

[0112] U12 is an n-type transistor.

[0113] As shown in Figure 5, the third delay sub-circuit includes a third resistor R3 and a third capacitor C3; the third switch sub-circuit includes a third switch transistor U13.

[0114] The first terminal of R3 is electrically connected to the PWM signal terminal PD, and the second terminal of R3 is electrically connected to the gate of U13; the first terminal of C3 is electrically connected to the second terminal of R3, and the second terminal of C3 is electrically connected to the ground terminal GND.

[0115] The source of U13 is electrically connected to the third drive current output terminal CH3, and the drain of U13 is electrically connected to the third backlight current supply terminal IFB3.

[0116] U13 is an n-type transistor.

[0117] As shown in Figure 6, the fourth delay sub-circuit includes a fourth resistor R4 and a fourth capacitor C4; the fourth switch sub-circuit includes a fourth switch transistor U14.

[0118] The first terminal of R4 is electrically connected to the PWM signal terminal PD, and the second terminal of R4 is electrically connected to the gate of U14; the first terminal of C4 is electrically connected to the second terminal of R4, and the second terminal of C4 is electrically connected to the ground terminal GND.

[0119] The source of U14 is electrically connected to the fourth drive current output terminal CH4, and the drain of U14 is electrically connected to the fourth backlight current supply terminal IFB4.

[0120] U14 is an n-type transistor.

[0121] As shown in Figure 7, the fifth delay sub-circuit includes a fifth resistor R5 and a fifth capacitor C5; the fifth switch sub-circuit includes a fifth switch transistor U15.

[0122] The first terminal of R5 is electrically connected to the PWM signal terminal PD, and the second terminal of R5 is electrically connected to the gate of U15; the first terminal of C5 is electrically connected to the second terminal of R5, and the second terminal of C5 is electrically connected to the ground terminal GND.

[0123] The source of U15 is electrically connected to the fifth drive current output terminal CH5, and the drain of U15 is electrically connected to the fifth backlight current supply terminal IFB5.

[0124] U15 is an n-type transistor.

[0125] As shown in Figure 8, the sixth delay sub-circuit includes a sixth resistor R6 and a sixth capacitor C6; the sixth switch sub-circuit includes a sixth switch transistor U16.

[0126] The first terminal of R6 is electrically connected to the PWM signal terminal PD, and the second terminal of R6 is electrically connected to the gate of U16; the first terminal of C6 is electrically connected to the second terminal of R6, and the second terminal of C6 is electrically connected to the ground terminal GND.

[0127] The source of U16 is electrically connected to the sixth drive current output terminal CH6, and the drain of U16 is electrically connected to the sixth backlight current supply terminal IFB6.

[0128] U16 is an n-type transistor.

[0129] As shown in Figure 9, based on at least one embodiment shown in Figure 1, a waveform diagram of the PWM signal provided by the PWM signal terminal PD is added.

[0130] In at least one embodiment of the backlight module described in this disclosure, during operation, a PWM signal is provided to the first terminal of R1 in the first delay sub-circuit, the first terminal of R2 in the second delay sub-circuit, the first terminal of R3 in the third delay sub-circuit, the first terminal of R4 in the fourth delay sub-circuit, the first terminal of R5 in the fifth delay sub-circuit, and the first terminal of R6 in the sixth delay sub-circuit via the PWM signal terminal PD included in the timing controller Tc. The first delay sub-circuit controls the PWM signal to delay for a first delay time, the second delay sub-circuit controls the PWM signal to delay for a second delay time, the third delay sub-circuit controls the PWM signal to delay for a third delay time, and the fourth delay sub-circuit controls... The PWM signal is delayed for a fourth delay time, the fifth delay sub-circuit controls the PWM signal to delay for a fifth delay time, and the sixth delay sub-circuit controls the PWM signal to delay for a sixth delay time. The second delay time is greater than the first delay time, the third delay time is greater than the second delay time, the fourth delay time is greater than the third delay time, the fifth delay time is greater than the fourth delay time, and the sixth delay time is greater than the fifth delay time. U11, U12, U13, U14, U15, and U16 are turned on in sequence, controlling the first light-emitting unit E1, the second light-emitting unit E2, the third light-emitting unit E3, the fourth light-emitting unit E4, the fifth light-emitting unit E5, and the sixth light-emitting unit E6 to light up in sequence.

[0131] In at least one embodiment of this disclosure, a GPIO (General-purpose input / output) pin of the timing controller Tc is configured to output a stable high and low level PWM signal. The timing and duty cycle of the PWM signal are set internally by the timing controller Tc to be consistent with the timing and duty cycle of the input PWM signal of the user interface.

[0132] In at least one embodiment of this disclosure, each delay sub-circuit achieves signal delay output by controlling the charging or discharging process of the capacitor. When an input signal is applied to the delay sub-circuit, the capacitor is charged. The charging time depends on the capacitance value of the capacitor and the resistance value of the resistor. The output signal will only appear when the capacitor is charged to a certain level. Therefore, each delay sub-circuit can precisely control the delay time of the output signal. When the resistance value of the resistor and the capacitance value of the capacitor are increased, the delay time of the delay sub-circuit will increase accordingly.

[0133] According to the formula for calculating the delay time: ty=Rz×Cz, where ty is the delay time, Rz is the resistance value of the resistors included in the delay sub-circuit, and Cz is the capacitance value of the capacitors included in the delay sub-circuit.

[0134] tyi = Riz × Ciz;

[0135] tyi+1=Ri+1z×Ci+1z;

[0136] Δt i = tyi+1-tyi;

[0137] tyi is the i-th delay time corresponding to the i-th delay sub-circuit, tyi+1 is the (i+1)-th delay time corresponding to the (i+1)-th delay sub-circuit, and Δt i Let Δt be the i-th interval time. Δt can be determined based on the interval time required by the actual project. i And determine Riz and Ciz accordingly, where i is a positive integer;

[0138] Riz is the resistance value of the i-th resistor, Ciz is the capacitance value of the i-th capacitor, Ri+1z is the resistance value of the (i+1)-th resistor, and Ci+1z is the capacitance value of the (i+1)-th capacitor.

[0139] As shown in Figure 10, the delay sub-circuit includes a resistor R and a capacitor C;

[0140] In Figure 10, the symbol S represents a switch, the symbol E represents a power supply, and the symbol Uo represents the output voltage of the delay sub-circuit.

[0141] As shown in Figure 11, when capacitor C is charged so that Uo equals Ue, the conduction threshold voltage of the switching transistor is reached, the switching transistor is fully turned on, and the driving integrated circuit can drive the light-emitting unit. Ue is the power supply voltage provided by E.

[0142] In Figure 11, the label t represents time, and the label t0 represents charging time.

[0143] In at least one embodiment of the backlight module described in this disclosure, the capacitor C1 is charged first during operation. After a first time t1, U11 is turned on, and the first light-emitting unit is lit. Then, after a second time t2, U12 is turned on, and the second light-emitting unit is lit. Then, after a third time t3, U13 is turned on, and the third light-emitting unit is lit. Then, after a fourth time t4, U14 is turned on, and the fourth light-emitting unit is lit. Then, after a fifth time t5, U15 is turned on, and the fifth light-emitting unit is lit. Then, after a sixth time t6, U16 is turned on, and the sixth light-emitting unit is lit. This achieves the sequential lighting of the first, second, third, fourth, fifth, and sixth light-emitting units, reducing the backlight flickering effect.

[0144] Optionally, the light-emitting unit includes multiple LEDs (light-emitting diodes) connected in series.

[0145] As shown in Figure 12, based on at least one embodiment shown in Figure 2,

[0146] The first light-emitting unit E1 includes multiple LEDs connected in series;

[0147] The second light-emitting unit E2 includes multiple LEDs connected in series;

[0148] The third light-emitting unit E3 includes multiple LEDs connected in series;

[0149] The fourth light-emitting unit E4 includes multiple LEDs connected in series;

[0150] The fifth light-emitting unit E5 includes multiple LEDs connected in series;

[0151] The sixth light-emitting unit E6 includes multiple LEDs connected in series.

[0152] The backlight module described in at least one embodiment of this disclosure further includes a backlight adjustment unit;

[0153] The backlight adjustment unit includes a control signal supply circuit and a switching circuit; the switching circuit includes N switching sub-circuits; N is a positive integer; n is a positive integer less than or equal to N;

[0154] The control signal providing circuit is electrically connected to the control terminal of the plurality of switch sub-circuits and is used to provide corresponding switch control signals to the control terminal of the switch sub-circuit.

[0155] The nth switch sub-circuit is electrically connected to the nth backlight current providing terminal and the nth light-emitting unit, respectively, and is used to write the nth backlight current provided by the nth backlight current providing terminal into the nth light-emitting unit during the nth light-emitting stage.

[0156] As shown in Figure 13, the backlight module of at least one embodiment of this disclosure includes a backlight adjustment unit, a first light-emitting unit E1, a second light-emitting unit E2, a third light-emitting unit E3, a fourth light-emitting unit E4, a fifth light-emitting unit E5, and a sixth light-emitting unit E6; N equals 6;

[0157] The backlight adjustment unit includes a control signal providing circuit 131 and a switching circuit 21;

[0158] The switching circuit 21 includes a first switching sub-circuit K1, a second switching sub-circuit K2, a third switching sub-circuit K3, a fourth switching sub-circuit K4, a fifth switching sub-circuit K5, and a sixth switching sub-circuit K6;

[0159] The control signal providing circuit 131 is electrically connected to the control terminals of K1, K2, K3, K4, K5, and K6 respectively, and is used to provide a first switch control signal to the control terminal of K1, a second switch control signal to the control terminal of K2, a third switch control signal to the control terminal of K3, a fourth switch control signal to the control terminal of K4, a fifth switch control signal to the control terminal of K5, and a sixth switch control signal to the control terminal of K6.

[0160] K1 is electrically connected to the first backlight current providing terminal CH1 and the first light-emitting unit E1 respectively. K1 is used to write the first backlight current provided by the first backlight current providing terminal CH1 into the first light-emitting unit E1 during the first light-emitting stage.

[0161] K2 is electrically connected to the second backlight current providing terminal CH2 and the second light-emitting unit E2 respectively. K2 is used to write the second backlight current provided by the second backlight current providing terminal CH2 into the second light-emitting unit E2 during the second light-emitting stage.

[0162] K3 is electrically connected to the third backlight current providing terminal CH3 and the third light-emitting unit E3 respectively. K3 is used to write the third backlight current provided by the third backlight current providing terminal CH3 into the third light-emitting unit E3 during the third light-emitting stage.

[0163] K4 is electrically connected to the fourth backlight current providing terminal CH4 and the fourth light-emitting unit E4 respectively. K4 is used to write the fourth backlight current provided by the fourth backlight current providing terminal CH4 into the fourth light-emitting unit E4 during the fourth light-emitting stage.

[0164] K5 is electrically connected to the fifth backlight current providing terminal CH5 and the fifth light-emitting unit E5 respectively. K5 is used to write the fifth backlight current provided by the fifth backlight current providing terminal CH5 into the fifth light-emitting unit E5 during the fifth light-emitting stage.

[0165] K6 is electrically connected to the sixth backlight current providing terminal CH6 and the sixth light-emitting unit E6 respectively. K6 is used to write the sixth backlight current provided by the sixth backlight current providing terminal CH6 into the sixth light-emitting unit E6 during the sixth light-emitting stage.

[0166] In at least one embodiment of this disclosure, the control signal providing circuit includes N delay sub-circuits;

[0167] The nth delay sub-circuit is electrically connected to the control terminal of the PWM signal terminal and the control terminal of the nth switch sub-circuit, respectively, and is used to control the PWM signal provided by the PWM signal terminal to be delayed by the nth delay time to obtain the nth switch control signal, and to provide the nth switch control signal to the control terminal of the nth switch sub-circuit.

[0168] As shown in Figure 14, based on at least one embodiment shown in Figure 13, the control signal providing circuit includes a first delay sub-circuit Y1, a second delay sub-circuit Y2, a third delay sub-circuit Y3, a fourth delay sub-circuit Y4, a fifth delay sub-circuit Y5, and a sixth delay sub-circuit Y6.

[0169] The first delay sub-circuit Y1 is electrically connected to the control terminal of the PWM signal terminal PD and the control terminal of the first switch sub-circuit K1, respectively, and is used to control the PWM signal provided by the PWM signal terminal PD to be delayed by a first delay time to obtain a first switch control signal, and to provide the first switch control signal to the control terminal of the first switch sub-circuit K1.

[0170] The second delay sub-circuit Y2 is electrically connected to the control terminal of the PWM signal terminal PD and the control terminal of the second switch sub-circuit K2, respectively, and is used to control the PWM signal provided by the PWM signal terminal PD to be delayed by a second delay time to obtain a second switch control signal, and to provide the second switch control signal to the control terminal of the second switch sub-circuit K2.

[0171] The third delay sub-circuit Y3 is electrically connected to the control terminal of the PWM signal terminal PD and the control terminal of the third switch sub-circuit K3, respectively. It is used to control the PWM signal provided by the PWM signal terminal PD to be delayed by a third delay time to obtain the third switch control signal, and to provide the third switch control signal to the control terminal of the third switch sub-circuit K3.

[0172] The fourth delay sub-circuit Y4 is electrically connected to the control terminal of the PWM signal terminal PD and the control terminal of the fourth switch sub-circuit K4, respectively. It is used to control the PWM signal provided by the PWM signal terminal PD to be delayed by a fourth delay time to obtain the fourth switch control signal, and to provide the fourth switch control signal to the control terminal of the fourth switch sub-circuit K4.

[0173] The fifth delay sub-circuit Y5 is electrically connected to the control terminal of the PWM signal terminal PD and the control terminal of the fifth switch sub-circuit K5, respectively, and is used to control the PWM signal provided by the PWM signal terminal PD to be delayed by a fifth delay time to obtain the fifth switch control signal, and to provide the fifth switch control signal to the control terminal of the fifth switch sub-circuit K5;

[0174] The sixth delay sub-circuit Y6 is electrically connected to the control terminal of the PWM signal terminal PD and the control terminal of the sixth switch sub-circuit K6, respectively. It is used to control the PWM signal provided by the PWM signal terminal PD to be delayed by a sixth delay time to obtain the sixth switch control signal, and to provide the sixth switch control signal to the control terminal of the sixth switch sub-circuit K6.

[0175] The driving method described in this embodiment is applied to the aforementioned backlight module; the driving method includes:

[0176] Control multiple light-emitting units to light up sequentially.

[0177] In at least one embodiment of this disclosure, the duration for which the light-emitting unit is continuously turned on is te; the backlight module includes N light-emitting units; N is an integer greater than 1; te is the light-emitting time; the driving method includes:

[0178] Control the lighting time of the m-th light-emitting unit and the lighting time of the (m+1)-th light-emitting unit, with an interval of a×te;

[0179] Where a is a positive number, a is greater than 0 and less than 1, m is a positive integer, and m+1 is less than or equal to N.

[0180] The driving method described in at least one embodiment of this disclosure includes:

[0181] The lighting time of the bth light-emitting unit of the Nth light-emitting unit is set before the lighting time of the (b+1)th light-emitting unit of the first light-emitting unit.

[0182] The interval between the b-th lighting time of the Nth light-emitting unit and the b+1-th lighting time of the first light-emitting unit is controlled to be c×te;

[0183] c is a positive number, greater than 0 and less than 1.

[0184] In at least one embodiment of this disclosure, the backlight module further includes a backlight adjustment unit; the backlight adjustment unit includes a control signal providing circuit and a switching circuit; the switching circuit includes N switching sub-circuits; N is a positive integer; n is a positive integer less than or equal to N; the light emission period of the backlight module includes N light emission stages; the driving method includes:

[0185] The control signal providing circuit provides the corresponding switching control signal to the control terminal of the switching sub-circuit;

[0186] The nth switch sub-circuit writes the nth backlight current into the nth light-emitting unit during the nth light-emitting stage;

[0187] The start times of the N luminescence stages are different.

[0188] In at least one embodiment of this disclosure, the control signal providing circuit includes N delay sub-circuits;

[0189] The step of the control signal providing circuit providing the corresponding switch control signal to the control terminal of the switch sub-circuit includes:

[0190] The nth delay sub-circuit controls the PWM signal to be delayed by the nth delay time to obtain the nth switch control signal, and provides the nth switch control signal to the control terminal of the nth switch sub-circuit.

[0191] In at least one embodiment of this disclosure, the (n+1)th delay time is greater than the nth delay time.

[0192] The display device described in this embodiment includes the backlight module and the liquid crystal display panel described above.

[0193] The liquid crystal display panel is located on the light-emitting side of the module.

[0194] The above description represents the preferred embodiments of this disclosure. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles described herein, and these improvements and modifications should also be considered within the scope of protection of this disclosure.

Claims

1. A backlight module comprising multiple light-emitting units; The multiple light-emitting units are lit up sequentially; The multiple light-emitting units emit the same color.

2. The backlight module as described in claim 1, wherein, The duration for which the light-emitting unit is continuously turned on at one time is te; the backlight module includes N light-emitting units; N is an integer greater than 1; te is the light-emitting time; The lighting time of the m-th light-emitting unit and the lighting time of the (m+1)-th light-emitting unit are separated by a×te; where a is a positive number, greater than 0 and less than 1, m is a positive integer, and m+1 is less than or equal to N.

3. The backlight module as described in claim 2, wherein, The b-th lighting time of the Nth light-emitting unit is set before the b+1-th lighting time of the first light-emitting unit; The interval between the b-th lighting time of the Nth light-emitting unit and the b+1-th lighting time of the first light-emitting unit is c×te; c is a positive number, greater than 0 and less than 1.

4. The backlight module as described in any one of claims 1 to 3, wherein, It also includes driver integrated circuits, timing controllers, switching circuits, and delay circuits; The driving integrated circuit includes N driving current output terminals, the switching circuit includes N switching sub-circuits, the delay circuit includes N delay sub-circuits, and the timing controller includes a PWM signal terminal. The driving integrated circuit includes an nth driving current output terminal that is electrically connected to the first terminal of the nth switch sub-circuit. The input terminal of the nth delay sub-circuit is electrically connected to the PWM signal terminal, the output terminal of the nth delay sub-circuit is electrically connected to the control terminal of the nth switch sub-circuit, and the second terminal of the nth switch sub-circuit is electrically connected to the nth backlight current supply terminal. The nth light-emitting unit is electrically connected to the nth backlight current providing terminal; n is a positive integer, and n is less than or equal to N.

5. The backlight module as described in claim 4, wherein, The nth delay sub-circuit includes an nth resistor and an nth capacitor; The first terminal of the nth resistor is electrically connected to the PWM signal terminal, and the nth resistor's first terminal is electrically connected to the PWM signal terminal. The two terminals are electrically connected to the control terminal of the nth switch sub-circuit; The first terminal of the nth capacitor is electrically connected to the second terminal of the nth resistor, and the second terminal of the nth capacitor is electrically connected to the DC voltage terminal.

6. The backlight module as described in claim 4, wherein, The nth switch sub-circuit includes the nth switch transistor; The gate of the nth switching transistor is electrically connected to the control terminal of the nth switching sub-circuit, the first terminal of the nth switching transistor is electrically connected to the first terminal of the nth switching circuit, and the second terminal of the nth switching transistor is electrically connected to the second terminal of the nth switching circuit.

7. The backlight module as described in claim 4, wherein, The light-emitting unit includes multiple LEDs connected in series.

8. The backlight module as described in any one of claims 1 to 3, wherein, It also includes a backlight adjustment unit; The backlight adjustment unit includes a control signal supply circuit and a switching circuit; the switching circuit includes N switching sub-circuits; N is a positive integer; n is a positive integer less than or equal to N; The control signal providing circuit is electrically connected to the control terminal of the plurality of switch sub-circuits and is used to provide corresponding switch control signals to the control terminal of the switch sub-circuit. The nth switch sub-circuit is electrically connected to the nth backlight current providing terminal and the nth light-emitting unit, respectively, and is used to write the nth backlight current provided by the nth backlight current providing terminal into the nth light-emitting unit during the nth light-emitting stage.

9. The backlight module as described in claim 8, wherein, The control signal providing circuit includes N delay sub-circuits; The nth delay sub-circuit is electrically connected to the control terminal of the PWM signal terminal and the control terminal of the nth switch sub-circuit, respectively, and is used to control the PWM signal provided by the PWM signal terminal to be delayed by the nth delay time to obtain the nth switch control signal, and to provide the nth switch control signal to the control terminal of the nth switch sub-circuit.

10. A driving method applied to a backlight module as described in any one of claims 1 to 9; the driving method comprising: Control multiple light-emitting units to light up sequentially.

11. The driving method as described in claim 10, wherein, The duration for which the light-emitting unit is continuously turned on is te; the backlight module includes N light-emitting units; N is an integer greater than 1; te represents the emission time; the driving method includes: Control the lighting time of the m-th light-emitting unit and the lighting time of the (m+1)-th light-emitting unit, with an interval of a×te; Where a is a positive number, a is greater than 0 and less than 1, m is a positive integer, and m+1 is less than or equal to N.

12. The driving method as described in claim 10, wherein, include: The lighting time of the bth light-emitting unit of the Nth light-emitting unit is set before the lighting time of the (b+1)th light-emitting unit of the first light-emitting unit. The interval between the b-th lighting time of the Nth light-emitting unit and the b+1-th lighting time of the first light-emitting unit is controlled to be c×te; c is a positive number, greater than 0 and less than 1.

13. The driving method as described in claim 10, wherein, The backlight module further includes a backlight adjustment unit; the backlight adjustment unit includes a control signal supply circuit and a switching circuit; the switching circuit includes N switching sub-circuits; N is a positive integer; n is a positive integer less than or equal to N; The backlight module's light emission cycle includes N light emission stages; the driving method includes: The control signal providing circuit provides the corresponding switching control signal to the control terminal of the switching sub-circuit; The nth switch sub-circuit writes the nth backlight current into the nth light-emitting unit during the nth light-emitting stage; The start times of the N luminescence stages are different.

14. The driving method as described in claim 13, wherein, The control signal providing circuit includes N delay sub-circuits; The step of the control signal providing circuit providing the corresponding switch control signal to the control terminal of the switch sub-circuit includes: The nth delay sub-circuit controls the PWM signal to be delayed by the nth delay time to obtain the nth switch control signal, and provides the nth switch control signal to the control terminal of the nth switch sub-circuit.

15. The driving method as described in claim 14, wherein, The (n+1)th delay time is greater than the nth delay time.

16. A display device comprising a backlight module as described in any one of claims 1 to 10, and a liquid crystal display panel; The liquid crystal display panel is located on the light-emitting side of the module.

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