Display device and driving method thereof

Abstract

In a display device that switches the number of times light emission occurs per frame, a display control circuit outputs a control signal to a light emission control line drive circuit indicating the light emission period allocated to each frame. The light emission control line drive circuit generates a signal applied to the light emission control line by sequentially delaying this control signal. When the ratio of the light emission period between the preceding frame period and the subsequent frame period is the same, but the number of light emission periods differs, a transition frame period with a different ratio of light emission period between the preceding and subsequent frame periods is set. This prevents flickering when switching the number of times light emission occurs per frame.

Description

Technical Field

[0001] This invention relates to display devices, and in particular, to self-emissive display devices. Background Technology

[0002] In recent years, organic EL display devices, which incorporate pixel circuits using organic electroluminescence (EL) elements as light-emitting elements, have been put into practical use. However, the displayed images on organic EL display devices sometimes flicker. Therefore, to prevent flicker, many organic EL display devices use a method that makes the organic EL elements emit light multiple times during each frame. However, organic EL display devices using this method suffer from the problem of afterimages when displaying moving images.

[0003] Even in organic EL displays where the organic EL elements emit light once per frame, setting the frame rate above 60Hz can prevent flicker and reduce afterimages. However, increasing the frame rate increases the power consumption of the organic EL display.

[0004] In connection with the present invention, Patent Document 1 describes a video display device that sets multiple emission timings for each pixel during one frame, determines the dynamic image region contained in the frame image, and limits the emission of pixels in the dynamic image region to once.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 2008-185905 Summary of the Invention

[0008] The problem the invention aims to solve

[0009] To prevent flickering without increasing power consumption, an organic EL display device that switches the number of times light emission occurs during each frame can be considered. According to this organic EL display device, by setting the proportion of the light emission period during a frame to be the same before and after switching the number of light emission occurrences, it is possible to display with the same brightness before and after switching the number of light emission occurrences.

[0010] However, in the frame immediately following the switch in the number of emission cycles, the brightness observed by the observer will change to a different level than in the preceding and following frame periods (see below). Figure 13 (and its explanation). The observer will perceive this brightness change as flickering. Thus, in organic EL display devices that switch the number of times the light emission occurs during each frame, there will be a problem of the display flickering when the number of light emission occurs.

[0011] Therefore, providing a display device that can prevent flickering when switching the number of light emission cycles per frame is considered a technical problem.

[0012] Solution for solving the problem

[0013] The aforementioned technical problem can be solved, for example, by a display device comprising: a display unit including: a plurality of scan lines, a plurality of data lines, a plurality of light emission control lines, and a plurality of pixel circuits, each including a light emission element; a scan line driving circuit that drives the scan lines; a data line driving circuit that drives the data lines; a light emission control line driving circuit that drives the light emission control lines; and a display control circuit that outputs a control signal to the light emission control line driving circuit indicating a light emission period allocated to a frame period, wherein the light emission control line driving circuit generates a signal applied to the light emission control lines by sequentially delaying the control signal; and when the ratio of the light emission period between the preceding frame period and the subsequent frame period is the same but the number of light emission periods is different, a transition frame period with a different ratio of light emission period than the preceding frame period is provided between the preceding frame period and the subsequent frame period.

[0014] The aforementioned technical problem can also be solved by a driving method for a display device. The display device has a display section, which includes: a plurality of scan lines, a plurality of data lines, a plurality of light emission control lines, and a plurality of pixel circuits, each including a light emission element. The driving method for the display device includes: a step of driving the scan lines; a step of driving the data lines; a step of driving the light emission control lines; and a step of outputting a control signal representing a light emission period allocated to a frame period to the step of driving the light emission control lines. The step of driving the light emission control lines generates a signal applied to the light emission control lines by sequentially delaying the control signal. When the ratio of the light emission period between the preceding frame period and the following frame period is the same but the number of light emission periods is different, a transition frame period with a different ratio of light emission period between the preceding frame period and the following frame period is set.

[0015] Invention Effects

[0016] According to the above-described display device and its driving method, when switching the number of light emission events per frame period between the preceding frame period and the subsequent frame period, by setting a transition frame period between the preceding frame period and the subsequent frame period, and allocating a light emission period with a different ratio than the preceding frame period to the transition frame period, the brightness observed by the observer can be changed in the opposite direction to an appropriate degree, thus preventing flickering when switching the number of light emission events per frame period. Attached Figure Description

[0017] Figure 1 This is a block diagram showing the configuration of the display device according to the first embodiment.

[0018] Figure 2 yes Figure 1 The circuit diagram of the pixel circuit of the display device shown is shown.

[0019] Figure 3 yes Figure 2 The timing diagram of the pixel circuit is shown.

[0020] Figure 4 It is shown Figure 1 The diagram shows the block diagram of the light-emitting control line driving circuit of the display device.

[0021] Figure 5 yes Figure 4 The circuit diagram shown is for the unit circuit of the light-emitting control line driving circuit.

[0022] Figure 6 yes Figure 4 The timing diagram of the light-emitting control line driving circuit is shown.

[0023] Figure 7 It is shown Figure 1 The diagram shows the transmission start pulse of the display device.

[0024] Figure 8 It is shown Figure 1 The diagram shows the light-emitting state of the display device.

[0025] Figure 9 yes Figure 1 The timing diagram of the display device is shown.

[0026] Figure 10 It is shown Figure 1 The diagram shows the transmission start pulse of the display device.

[0027] Figure 11 It is shown Figure 1 The diagram shows the light-emitting state of the display device.

[0028] Figure 12 yes Figure 1 The timing diagram of the display device is shown.

[0029] Figure 13 This is a diagram showing the light-emitting state of an existing display device.

[0030] Figure 14 This is a diagram showing the transmission start pulse of the display device according to the second embodiment.

[0031] Figure 15 This is a diagram showing the light-emitting state of the display device according to the second embodiment.

[0032] Figure 16 This is a timing diagram of the display device according to the second embodiment.

[0033] Figure 17 This is a diagram showing the transmission start pulse of the display device according to the third embodiment.

[0034] Figure 18 This is a diagram showing the light-emitting state of the display device according to the third embodiment.

[0035] Figure 19 This is a timing diagram of the display device according to the third embodiment.

[0036] Figure 20 This is a diagram showing the transmission start pulse of the display device according to the third embodiment.

[0037] Figure 21 This is a diagram showing the light-emitting state of the display device according to the third embodiment.

[0038] Figure 22 This is a timing diagram of the display device according to the third embodiment.

[0039] Figure 23 This is a diagram showing the transmission start pulse of the display device according to the fourth embodiment.

[0040] Figure 24 This is a diagram showing the light-emitting state of the display device according to the fourth embodiment.

[0041] Figure 25 This is a timing diagram of the display device according to the fourth embodiment.

[0042] Figure 26 This is a diagram showing the transmission start pulse of the display device according to the fifth embodiment.

[0043] Figure 27 This is a diagram showing the light-emitting state of the display device according to the fifth embodiment.

[0044] Figure 28 This is a timing diagram of the display device according to the fifth embodiment.

[0045] Figure 29 This is a diagram showing the transmission start pulse of the display device according to the fifth embodiment.

[0046] Figure 30 This is a diagram showing the light-emitting state of the display device according to the fifth embodiment.

[0047] Figure 31 This is a timing diagram of the display device according to the fifth embodiment. Detailed Implementation

[0048] Hereinafter, the display device of each embodiment will be described with reference to the accompanying drawings. The display device of each embodiment is an organic EL display device having a pixel circuit including an organic EL element. An organic EL element is a type of light-emitting element, also known as an organic light-emitting diode or OLED (Organic Light Emitting Diode). In the following description, the horizontal direction of the drawings is referred to as the row direction, and the vertical direction of the drawings is referred to as the column direction. Furthermore, m and n are integers of 2 or more, i is an integer of 1 or more and less than m, and j is an integer of 1 or more and less than n.

[0049] (First Embodiment)

[0050] Figure 1 This is a block diagram showing the configuration of the display device according to the first embodiment. Figure 1 The display device 10 shown includes: a display unit 11, a display control circuit 12, a scan line drive circuit 13, a data line drive circuit 14, and a light emission control line drive circuit 15.

[0051] The display unit 11 includes (m+1) scan lines G0 to Gm, n data lines S1 to Sn, m light-emitting control lines E1 to Em, and (m×n) pixel circuits 20. The scan lines G0 to Gm extend in the row direction and are arranged parallel to each other. The data lines S1 to Sn extend in the column direction and are arranged parallel to each other in a manner orthogonal to the scan lines G1 to Gm. The light-emitting control lines E1 to Em extend in the row direction and are arranged parallel to the scan lines G0 to Gm. The scan lines G1 to Gm intersect the data lines S1 to Sn at (m×n) points. The (m×n) pixel circuits 20 are arranged in a two-dimensional configuration corresponding to the intersections of the scan lines G1 to Gm and the data lines S1 to Sn. A high-level power supply voltage ELVDD, a low-level power supply voltage ELVSS, and an initialization voltage Vini are supplied to each pixel circuit 20 using conductive components (wiring or electrodes) not shown.

[0052] The display control circuit 12 outputs control signal CS1 to the scan line drive circuit 13, control signal CS2 and video signal VS to the data line drive circuit 14, and control signal CS3 to the light emission control line drive circuit 15. The scan line drive circuit 13 drives scan lines G0 to Gm based on control signal CS1. The data line drive circuit 14 drives data lines S1 to Sn based on control signal CS2 and video signal VS. The light emission control line drive circuit 15 drives light emission control lines E1 to Em based on control signal CS3.

[0053] More specifically, the scan line driving circuit 13 selects one scan line sequentially from scan lines G0 to Gm based on the control signal CS1, and applies a selection voltage (in this case, a low-level voltage) to the selected scan line. Consequently, the n pixel circuits 20 connected to the selected scan line are selected simultaneously. The data line driving circuit 14 applies n data voltages corresponding to the video signal VS to the data lines S1 to Sn respectively based on the control signal CS2. Thus, the selected n pixel circuits 20 are each written with n data voltages.

[0054] Each row of pixel circuits 20 is assigned a light-emitting period and a non-light-emitting period. The light-emitting control line driving circuit 15 applies a light-emitting voltage (here, a low-level voltage) to the light-emitting control line Ei during the light-emitting period of the i-th row of pixel circuits 20, and applies a non-light-emitting voltage (here, a high-level voltage) to the light-emitting control line Ei during the non-light-emitting period of the i-th row of pixel circuits 20. During the light-emitting period of the i-th row of pixel circuits 20, the organic EL elements within the i-th row of pixel circuits 20 emit light with a brightness corresponding to the data voltage written to the pixel circuits 20.

[0055] Figure 2 This is the circuit diagram of pixel circuit 20. Figure 2 The diagram contains the pixel circuit 20 in the i-th row and j-th column. Figure 2 The pixel circuit 20 shown includes: seven thin-film transistors (TFTs) Q1 to Q7, an organic EL element L1, and a capacitor C1. TFTs Q1 to Q7 are P-channel transistors. The pixel circuit 20 is connected to scan lines Gi-1 and Gi, data line Sj, and light emission control line Ei. Scan line Gi-1 is selected one level before scan line Gi.

[0056] Furthermore, the TFT included in the pixel circuit 20 can be an amorphous silicon transistor with a channel layer formed of amorphous silicon, a low-temperature polycrystalline silicon transistor with a channel layer formed of low-temperature polycrystalline silicon, or an oxide semiconductor transistor with a channel layer formed of oxide semiconductor. For example, indium gallium zinc oxide (IGZO) can be used as the oxide semiconductor. Additionally, the TFT included in the pixel circuit 20 can be either top-gate or bottom-gate type. Alternatively, a pixel circuit containing N-channel transistors can be used instead of a pixel circuit 20 containing P-channel transistors. When using N-channel transistors to construct the pixel circuit, simply reverse the polarity of the signal and power supply voltage supplied to the pixel circuit.

[0057] TFT: The source terminal of Q5 and one electrode of capacitor C1 (in) Figure 2The upper electrode (in the middle) is supplied with a high-level power supply voltage ELVDD. TFT: One of the conducting terminals of Q3 (in...) Figure 2 The right-hand conducting terminal (in the middle) is connected to data line Sj. The drain terminal of TFT: Q5 and the other conducting terminal of TFT: Q3 are connected to the source terminal of TFT: Q4. The drain terminal of TFT: Q4 is connected to one conducting terminal of TFT: Q2 (in the middle). Figure 2 The lower conducting terminal of TFT:Q2 is connected to the source terminal of TFT:Q6. The drain terminal of TFT:Q6 is connected to the anode terminal of organic EL element L1 and the source terminal of TFT:Q7. A low-level power supply voltage ELVSS is applied to the cathode terminal of organic EL element L1. The other conducting terminal of TFT:Q2 is connected to the gate terminal of TFT:Q4, the other electrode of capacitor C1, and the source terminal of TFT:Q1. An initialization voltage Vini is applied to the drain terminals of TFT:Q1 and Q7. The gate terminal of TFT:Q1 is connected to scan line Gi-1, the gate terminals of TFT:Q2, Q3, and Q7 are connected to scan line Gi, and the gate terminals of TFT:Q5 and Q6 are connected to the light emission control line Ei.

[0058] Figure 3 This is a timing diagram of pixel circuit 20. Before time t1, the voltages of scan lines Gi-1 and Gi are high, and the voltage of the light emission control line Ei is low. Therefore, TFTs Q1 to Q3 and Q7 are in the off state, and TFTs Q5 and Q6 are in the on state. At this time, if the gate-source voltage of TFT Q4 is below the threshold voltage of TFT Q4, the current flowing through TFTs Q5, Q4, Q6 and organic EL element L1 will flow from the conductive component with a high-level power supply voltage ELVDD to the conductive component with a low-level power supply voltage ELVSS, and organic EL element L1 will emit light with a brightness corresponding to the amount of flowing current.

[0059] At time t1, the voltage of scan line Gi-1 goes low, and the voltage of the light-emitting control line Ei goes high. Simultaneously, TFT:Q1 turns on, while TFTs:Q5 and Q6 turn off. Since TFTs:Q5 and Q6 are off, after time t1, the current flowing through the organic EL element L1 ceases, and the organic EL element L1 stops emitting light. Since TFT:Q1 turns on, the gate voltage of TFT:Q4 becomes equal to the initialization voltage Vini. The initialization voltage Vini is set to a low level immediately after the voltage of scan line Gi goes low (just after time t2) at which TFT:Q4 turns on.

[0060] Next, at time t2, the voltage of scan line Gi-1 becomes high, and the voltage of scan line Gi becomes low. Simultaneously, TFT: Q1 is turned off, and TFTs: Q2, Q3, and Q7 are turned on. Because TFT: Q7 is turned on, the voltage at the anode terminal of organic EL element L1 becomes equal to the initialization voltage Vini. Because TFT: Q2 is turned on, TFT: Q4 becomes diode-connected. Therefore, current flows through TFTs: Q3, Q4, and Q2 from data line Sj towards the gate terminal of TFT: Q4, and the gate voltage of TFT: Q4 rises. Current stops flowing when the gate-source voltage of TFT: Q4 becomes equal to its threshold voltage. When the threshold voltage of TFT: Q4 is set to Vth (<0), and the data voltage applied to data line Sj between time t2 and time t3 is set to Vd, the gate voltage of TFT: Q4 before time t3 is (Vd - |Vth|).

[0061] Next, at time t3, the voltage of scan line Gi goes high. Simultaneously, TFTs Q2, Q3, and Q7 are turned off. After time t3, capacitor C1 maintains the inter-electrode voltage (ELVDD-Vd+|Vth|).

[0062] Next, at time t4, the voltage of the light-emitting control line Ei goes low. Simultaneously, TFTs Q5 and Q6 turn on. After time t4, current flows through TFTs Q5, Q4, Q6 and the organic EL element L1 from the conductive component with a high-level supply voltage ELVDD to the conductive component with a low-level supply voltage ELVSS. The gate-source voltage Vgs of TFT Q4 is maintained at (ELVDD - Vd + |Vth|) by the capacitor C1. Therefore, after time t4, the current Id flowing through the organic EL element L1 is given by the constant K using equation (1).

[0063] Id = K(Vgs - |Vth|) 2

[0064] =K(ELVDD-Vd+|Vth|-|Vth|) 2

[0065] =K(ELVDD-Vd) 2 …(1)

[0066] After time t4, regardless of the threshold voltage Vth of TFT:Q4, the organic EL element L1 emits light with a brightness corresponding to the data voltage Vd written to the pixel circuit 20.

[0067] Figure 4 This is a block diagram showing the configuration of the light-emitting control line driving circuit 15. Figure 4 The illustrated light-emitting control line drive circuit 15 has a configuration that connects m unit circuits 30 in multiple stages. Each unit circuit 30 has: a clock terminal CK, a clock terminal CKB, an input terminal IN, and an output terminal OUT.

[0068] The control signal CS3 output from the display control circuit 12 to the light emission control line drive circuit 15 includes a two-phase transmission clock EMCK1, EMCK2, and a transmission start pulse EMSP. The transmission clock EMCK1 is provided to the clock terminal CK of all levels of the unit circuit 30. The transmission clock EMCK2 is the negation signal of the transmission clock EMCK1 and is provided to the clock terminal CKB of all levels of the unit circuit 30. The transmission start pulse EMSP is provided to the input terminal IN of the first-level unit circuit 30. The input terminals IN of the second to m-th level unit circuits 30 are respectively provided with signals output from the output terminals OUT of the first to (m-1)-th level unit circuits 30. The output terminals OUT of the first to m-th level unit circuits 30 are respectively connected to the light emission control lines E1 to Em.

[0069] Figure 5 This is the circuit diagram of unit circuit 30. Figure 5 The unit circuit 30 shown includes four clocked inverters M1, M3, M4, and M6, and two inverters M2 and M5. The input terminal of clocked inverter M1 is connected to the input terminal IN of unit circuit 30. The output terminals of clocked inverters M1 and M3 are connected to the input terminal of inverter M2. The output terminal of inverter M2 is connected to the input terminals of clocked inverters M3 and M4. The output terminals of clocked inverters M4 and M6 are connected to the input terminal of inverter M5. The output terminal of inverter M5 is connected to the input terminal of clocked inverter M6 and the output terminal OUT of unit circuit 30.

[0070] When the signal input from the clock terminal CK is high, the clock-controlled inverters M1 and M6 function as inverters, and the output signals of the clock-controlled inverters M3 and M4 become high-impedance. When the signal input from the clock terminal CK is low, the clock-controlled inverters M3 and M4 function as inverters, and the output signals of the clock-controlled inverters M1 and M6 become high-impedance.

[0071] Therefore, in unit circuit 30, when the signal input from clock terminal CK changes from low level to high level, the signal input from input terminal IN is held at node N1. Additionally, when the signal input from clock terminal CK changes from high level to low level, the signal held at node N1 is output from output terminal OUT.

[0072] Figure 6This is the timing diagram of the light-emitting control line driver circuit 15. (Example) Figure 6 As shown, the period of the transmit clock EMCK1 is one horizontal period (1H). The transmit start pulse EMSP is high for a period of the same length as k horizontal periods (k being an integer greater than or equal to 1). The voltage of the light emission control line E1 changes in the same way as the transmit start pulse EMSP, with a delay of less than one horizontal period compared to the transmit start pulse EMSP. The voltage of the light emission control line E2 changes with a delay of one horizontal period compared to the voltage of the light emission control line E1. Similarly, the voltage of the light emission control line Ei changes with a delay of one horizontal period compared to the voltage of the light emission control line Ei-1. Therefore, the voltages of the light emission control lines E1 to Em are each delayed by one horizontal period and are high for k horizontal periods.

[0073] The display device 10 has the function of switching the number of times light is emitted per frame (hereinafter also referred to as "light emission count"). The display control circuit 12 allocates N light emission periods and N non-light emission periods to a frame period with N light emission counts (N is an integer greater than or equal to 1), and outputs a transmit start pulse EMSP as a control signal indicating the light emission periods allocated to the frame period. Hereinafter, the proportion of light emission periods allocated to the frame period is referred to as the "duty cycle". For example, if two non-light emission periods of length Tx are allocated to a frame period of length Tf, the duty cycle of the frame period is (Tf - 2Tx) / Tf. The organic EL element L1 emits light when the voltage of the corresponding light emission control line is low. Therefore, the duty cycle can also be described as the proportion of the length of the period when the voltage of the light emission control line is low to the length of one frame period. For example, if the voltage of the light emission control line is always low during one frame period, the duty cycle is 100%.

[0074] The display device 10 switches the number of times the light is emitted between once and twice. Figure 7 This is a diagram showing the emission initiation pulse (EMSP) when the display device 10 switches the emission frequency from 2 times to 1 time. Figure 8 This is a diagram showing the luminescence state at this time. Figure 9 This is the timing diagram at this point. In the attached diagram showing the luminous state, white parallelograms represent luminous parts, parallelograms with dotted patterns represent non-luminous parts, and dashed lines represent the data voltage writing positions. To make the diagram easier to read, one horizontal period in the timing diagram is recorded as longer than it actually is.

[0075] exist Figure 7 The document records the transmit start pulse (EMSP) during four consecutive frame periods F11–F14. The transmit start pulse (EMSP) occurs as follows during frame periods F11–F14: Figure 8The voltages of the emission control lines E1 to Em change sequentially with a delay of one level period, similar to the emission start pulse EMSP (see reference). Figure 9 The organic EL element L1 in the i-th row pixel circuit 20 emits light when the voltage of the light emission control line Ei is low, and does not emit light when the voltage of the light emission control line Ei is high. The display unit 11 in... Figure 8 The light-emitting part shown emits light, while other parts do not.

[0076] like Figure 7 As shown, frame period F11 is allocated two emission periods and two non-emission periods with a length Tx. Frame period F14 is allocated one emission period and one non-emission period with a length of 2Tx. Although the number of emission periods differs between frame periods F11 and F14, their duty cycles are the same.

[0077] Two frame periods, F12 and F13, are set between frame period F11 and frame period F14. Frame period F12 is allocated one luminous period and one non-luminous period with length Ta. Frame period F13 is allocated one luminous period and one non-luminous period with length Tb. Between lengths Tx, Ta, and Tb, the following equation (2) holds.

[0078] Tx < Ta < 2Tx < Tb…(2)

[0079] Therefore, the duty cycle of frame period F12 is greater than that of frame period F11. The duty cycle of frame period F13 is less than that of frame period F11. The duty cycles of frame periods F12 and F13 are different.

[0080] Frame periods F11 to F14 correspond to the preceding frame period, the first transition frame period, the second transition frame period, and the subsequent frame period, respectively. When the ratio of the light emission periods between the preceding frame period F11 and the subsequent frame period F14 is the same but the number of light emission periods is different, a first transition frame period F12 and a second transition frame period F13 with a different ratio of light emission periods than the preceding frame period F11 are set between the preceding frame period F11 and the subsequent frame period F14.

[0081] During the preceding frame period F11, two emission periods are allocated, and during the subsequent frame period F14, one emission period is allocated. During the first transition frame period F12, an emission period with a start timing different from both the preceding frame period F11 and the subsequent frame period F14 is set. During the second transition frame period F13, an emission period with a start timing different from both the preceding frame period F11 and the subsequent frame period F14 is set.

[0082] During the first transition frame period F12 and the second transition frame period F13, different emission periods are set compared to the preceding frame period F11 and the subsequent frame period F14. The first transition frame period F12 and the second transition frame period F13 are allocated the same number of emission periods as the subsequent frame period F14. The ratio of emission periods differs between the first transition frame period F12 and the second transition frame period F13. The second transition frame period F13 is allocated emission periods with start and end timings that differ from those in the first transition frame period F12.

[0083] During the subsequent frame period F14, fewer light-emitting periods are allocated compared to the preceding frame period F11. During the first transition frame period F12, fewer light-emitting periods are allocated compared to the preceding frame period F11, but in a larger proportion. During the second transition frame period F13, the same number of light-emitting periods are allocated compared to the first transition frame period F12, but in a smaller proportion. During the subsequent frame period F14, the same number of light-emitting periods are allocated as the second transition frame period F13.

[0084] Figure 10 This is a diagram showing the emission initiation pulse (EMSP) when the display device 10 switches the emission frequency from 1 to 2 times. Figure 11 This is a diagram showing the luminescence state at this time. Figure 12 This is the timing diagram at this point. During frame periods F21 to F23, the transmit start pulse EMSP is as follows: Figure 10 and Figure 11 The display unit 11 changes as shown. Figure 11 The light-emitting part shown emits light, while other parts do not.

[0085] like Figure 10 As shown, frame periods F21 and F23 are allocated emission periods in the same way as frame periods F14 and F11, respectively. Although the number of emission periods differs between frame periods F21 and F23, their duty cycles are the same.

[0086] A frame period F22 is set between frame period F21 and frame period F23. Frame period F22 is allocated as follows: two light-emitting periods, one non-light-emitting period with length Tc, and one non-light-emitting period with length Td. Between lengths Tx, Tc, and Td, the following equation (3) holds.

[0087] Td<Tx<Tc<2Tx<Tc+Td…(3)

[0088] Therefore, the duty cycle of F22 during frame period is less than the duty cycle of F21 during frame period.

[0089] Frame periods F21 to F23 correspond to the preceding frame period, the transition frame period, and the subsequent frame period, respectively. When the ratio of the light emission period between the preceding frame period F21 and the subsequent frame period F23 is the same but the number of light emission periods is different, a transition frame period F22 with a different ratio of light emission period than the preceding frame period F21 is set between the preceding frame period F21 and the subsequent frame period F23.

[0090] During the preceding frame period F21, one emission period is allocated, and during the subsequent frame period F23, two emission periods are allocated. During the transition frame period F22, the following emission periods are set: an emission period with a start timing different from both the preceding frame period F21 and the subsequent frame period F23, and emission periods with both start and end timings different from those of the subsequent frame period F23.

[0091] During subsequent frames, F23 is allocated more light-emitting periods than during the preceding frame, F21. During the transition frame, F22 is allocated more light-emitting periods than during the preceding frame, F21, but at a smaller proportion. During subsequent frames, F23 is allocated the same number of light-emitting periods as during the transition frame, F22, but at a larger proportion.

[0092] Hereinafter, as a comparative example, consider the following display device: when the ratio of the emission period between the preceding frame period and the subsequent frame period is the same but the number of emission periods is different, there is no transition frame period between the preceding frame period and the subsequent frame period. Figure 13 This diagram illustrates the illumination state of the comparative example display device when the number of light emission cycles is switched from 2 to 1. Figure 13 In this configuration, frame period F91 is allocated two emission periods, and frame period F92 is allocated one emission period. The duty cycle is the same between frame period F91 and frame period F92.

[0093] When comparing frame period F91 and frame period F92, in frame period F92, the direction that causes time to rewind is one of the two non-light-emitting periods allocated to frame period F91 (in... Figure 13 The middle (leftward direction) moves and connects to the other side of the two non-light-emitting periods allocated to frame period F91. When the same frame period occurs again after frame period F91... Figure 13 The X2 portion shown becomes a non-light-emitting portion, and when the next frame period F92 occurs after frame period F91, Figure 13 The X1 portion shown is a non-luminous portion. In the latter case, since a portion of the non-luminous portion appears earlier, the brightness observed by the observer (hereinafter referred to as the observed brightness) decreases during frame period F92 and the next frame period.

[0094] Conversely, when the display device in the comparative example switches the number of light emission cycles from 1 to 2, the observed brightness increases during frame period F92 and the next frame because a portion of the non-light-emitting part appears later. The observer will perceive these brightness changes as flickering. Thus, in the display device of the comparative example, the display screen flickers when the number of light emission cycles per frame is switched.

[0095] In contrast, in the display device 10 of this embodiment, when the ratio of the light-emitting period between the preceding frame period and the subsequent frame period is the same but the number of light-emitting periods is different, one or two transition frame periods with a different ratio of light-emitting period than the preceding frame period are provided between the preceding frame period and the subsequent frame period. The transition frame period may be allocated a light-emitting period with a start timing different from at least one of the preceding frame period and the subsequent frame period, or an end timing different from at least one of the preceding frame period and the subsequent frame period, or a light-emitting period different from both the preceding frame period and the subsequent frame period, or the same number of light-emitting periods as the subsequent frame period.

[0096] When the display device 10 switches the number of light emission cycles from 2 to 1, it allocates a light emission period with a larger proportion than the preceding frame period F11 to the first transition frame period F12, thereby making the duty cycle of the first transition frame period F12 greater than that of the preceding frame period F11, and thus increasing the observed brightness to an appropriate level. Furthermore, by allocating a light emission period with a smaller proportion than both the preceding frame period F11 and the first transition frame period F12 to the second transition frame period F13, it makes the duty cycle of the second transition frame period F13 smaller than that of both the preceding frame period F11 and the first transition frame period F12, preventing an excessive increase in observed brightness due to the setting of the first transition frame period F12.

[0097] When the display device 10 switches the number of light emission times from 1 to 2, it allocates a light emission period with a smaller ratio than the preceding frame period F21 to the transition frame period F22, so that the duty cycle of the transition frame period F22 is smaller than the duty cycle of the preceding frame period F21, thereby reducing the observed brightness to an appropriate level.

[0098] Therefore, according to the display device 10 of this embodiment, when switching the number of light emission times per frame period between the preceding frame period and the subsequent frame period, by setting a transition frame period between the preceding frame period and the subsequent frame period, and allocating the light emission period with a different ratio than the preceding frame period to the transition frame period, the observed brightness can be changed to an appropriate degree in the opposite direction, preventing flickering when switching the number of light emission times per frame period.

[0099] In the display device of the comparative example described above, the observed brightness decreases when the number of light emission cycles decreases and increases when the number of light emission cycles increases. However, the direction and extent of the change in observed brightness when switching the number of light emission cycles vary depending on factors such as the position of the light emission period allocated to the frame period. For example, there are also cases where the observed brightness increases when the number of light emission cycles decreases and decreases when the number of light emission cycles increases. Even in this case, as described above, by setting a transition frame period between the preceding frame period and the subsequent frame period, and allocating a light emission period with a different proportion than the preceding frame period to the transition frame period, flickering when switching the number of light emission cycles for each frame period can be prevented.

[0100] (Second Implementation)

[0101] The display device of the second embodiment has the same configuration as the display device 10 of the first embodiment. Figure 1 The display device in this embodiment switches the number of light emission cycles between 1 and 2. When switching the number of light emission cycles from 2 to 1, it uses the same emission initiation pulse (EMSP) as in the first embodiment. Figure 7 When switching the number of emission times from 1 to 2, a different emission initiation pulse EMSP is used than in the first embodiment.

[0102] Figure 14 This is a diagram showing the emission initiation pulse (EMSP) of the display device of this embodiment when the number of light emission cycles is switched from 1 to 2. Figure 15 This is a diagram showing the luminescence state at this time. Figure 16 This is the timing diagram at this point. During frame periods F31 to F34, the transmit start pulse EMSP is as follows: Figure 14 and Figure 15 The display unit 11 changes as shown. Figure 15 The light-emitting part shown emits light, while other parts do not.

[0103] like Figure 14 As shown, frame periods F31 and F34 are allocated emission periods in the same way as frame periods F14 and F11, respectively. Although the number of emission periods differs between frame periods F31 and F34, their duty cycles are the same.

[0104] Two frame periods, F32 and F33, are set between frame period F31 and frame period F34. Frame period F32 is allocated as follows: two light-emitting periods, one non-light-emitting period with length Tp, and one non-light-emitting period with length Tq. Frame period F33 is allocated as follows: two light-emitting periods, one non-light-emitting period with length Tr, and one non-light-emitting period with length Ts. Equations (4) and (5) hold true between lengths Tx, Tp, Tq, Tr, and Ts.

[0105] Tq<Ts<Tx<Tr<Tp<2Tx…(4)

[0106] Tr+Ts<2Tx<Tp+Tq…(5)

[0107] Therefore, the duty cycle of frame period F32 is less than that of frame period F31. The duty cycle of frame period F33 is greater than that of frame period F31. The duty cycles of frame period F32 and frame period F33 are different.

[0108] Frame periods F31 to F34 correspond to the preceding frame period, the first transition frame period, the second transition frame period, and the subsequent frame period, respectively. When the ratio of the light emission periods between the preceding frame period F31 and the subsequent frame period F34 is the same, but the number of light emission periods differs, a first transition frame period F32 and a second transition frame period F33, with a different ratio of light emission periods than the preceding frame period F31, are set between the preceding frame period F31 and the subsequent frame period F34. The ratio of the light emission periods between the first transition frame period F32 and the second transition frame period F33 is different. The second transition frame period F33 is assigned a light emission period with at least one of its start timing and end timing that is different from that of the first transition frame period F32.

[0109] During the preceding frame period F31, one emission period is allocated, and during the subsequent frame period F34, two emission periods are allocated. During the first transition frame period F32, there are emission periods with start timings different from both the preceding frame period F31 and the subsequent frame period F34, as well as emission periods with start and end timings different from those of the subsequent frame period F34. During the second transition frame period F33, there are emission periods with start timings different from both the preceding frame period F31 and the subsequent frame period F34, as well as emission periods with start and end timings different from those of the subsequent frame period F34. Both the first and second transition frame periods F32 and F33 have emission periods different from both the preceding and subsequent frame periods F31 and F34. The first and second transition frame periods F32 and F33 are allocated the same number of emission periods as the subsequent frame period F34. The ratio of emission periods between the first and second transition frame periods F32 and F33 is different. During the second transition frame, F33 is assigned a start timing and an end timing, both of which are different from the emission periods of F32 during the first transition frame.

[0110] During subsequent frames, F34 is allocated more light-emitting periods than the preceding frame, F31. During the first transition frame, F32 is allocated more light-emitting periods than the preceding frame, F31, but at a smaller proportion. During the second transition frame, F33 is allocated the same number of light-emitting periods as the first transition frame, F32, but at a larger proportion. During subsequent frames, F34 is allocated the same number of light-emitting periods as the second transition frame, F33.

[0111] In this embodiment, when the display device switches the number of light emission cycles from 1 to 2, by allocating a light emission period with a smaller proportion than the preceding frame period F31 to the first transition frame period F32, the duty cycle of the first transition frame period F32 is made smaller than the duty cycle of the preceding frame period F31, thus reducing the observed brightness to an appropriate level. Furthermore, by allocating a light emission period with a larger proportion than the preceding frame period F31 to the second transition frame period F33, the duty cycle of the second transition frame period F33 is made larger than the duty cycle of the preceding frame period F31, preventing excessive reduction in observed brightness due to the setting of the first transition frame period F32.

[0112] According to the display device of this embodiment, similarly to the first embodiment, when switching the number of light emission times per frame period between the preceding frame period and the subsequent frame period, by setting a transition frame period between the preceding frame period and the subsequent frame period, and allocating the light emission period with a different ratio than the preceding frame period to the transition frame period, the observed brightness can be changed in the opposite direction to an appropriate degree, preventing flickering when switching the number of light emission times per frame period.

[0113] (Third Implementation)

[0114] The display device of the third embodiment has the same configuration as the display device 10 of the first embodiment. Figure 1 The display device of this embodiment switches the number of light emission cycles when switching frame rates. It includes a first mode, which operates normally at a frame rate of 90Hz and a light emission cycle of 1; and a second mode, which operates in a rest mode at a frame rate of 60Hz and a light emission cycle of 3. The display device of this embodiment switches between the first and second modes. Furthermore, rest driving refers to a driving method that divides the frame period into a scanning period and a rest period, and stops writing data voltage during the rest period.

[0115] Figure 17 This is a diagram showing the transmission start pulse (EMSP) of the display device in this embodiment when it switches the operating mode from mode 1 to mode 2. Figure 18 This is a diagram showing the luminescence state at this time. Figure 19 This is the timing diagram at this point. During frame periods F41 to F44, the transmit start pulse EMSP is as follows: Figure 17 and Figure 18 The display unit 11 changes as shown. Figure 18 The light-emitting part shown emits light, while other parts do not.

[0116] like Figure 17As shown, frame period F41 is allocated a light emission period in the same way as frame period F14. The length of frame period F44 is 1.5 times the length of frame period F41. Two-thirds of frame period F44 is a scan period, and the remainder is a rest period. Frame period F44 is allocated 3 light emission periods and 3 non-light emission periods with a length Tx. Two frame periods F42 and F43 are set between frame period F41 and frame period F44. Frame periods F42 and F43 are allocated light emission periods in the same way as frame periods F32 and F33, respectively.

[0117] Frame periods F41 to F44 correspond to the preceding frame period, the first transition frame period, the second transition frame period, and the subsequent frame period, respectively. The preceding frame period F41, the first transition frame period F42, and the second transition frame period F43 are normal frame periods with only a scan period. The subsequent frame period F44 is a composite frame period with both a scan period and a rest period. The scan period of the subsequent frame period F44, as a composite frame period, is allocated the same proportion of illumination periods as the preceding frame period F41. This scan period is allocated the same number of illumination periods as the first transition frame period F42 and the second transition frame period F43.

[0118] Figure 20 This is a diagram showing the transmission start pulse (EMSP) of the display device in this embodiment when it switches the operating mode from mode 2 to mode 1. Figure 21 This is a diagram showing the luminescence state at this time. Figure 22 This is the timing diagram at this point. During frame periods F51 to F54, the transmit start pulse EMSP is as follows: Figure 20 and Figure 21 The display unit 11 changes as shown. Figure 21 The light-emitting part shown emits light, while other parts do not.

[0119] like Figure 20 As shown, frame period F54 is allocated a light emission period in the same way as frame period F14. The length of frame period F51 is 1.5 times the length of frame period F54. Two-thirds of frame period F51 is a scan period, and the remaining part is a rest period. Frame period F51 is allocated a light emission period in the same way as frame period F44. Two frame periods F52 and F53 are set between frame periods F51 and F54. Frame periods F52 and F53 are allocated a light emission period in the same way as frame periods F12 and F13, respectively.

[0120] Frame periods F51 to F54 correspond to the preceding frame period, the first transition frame period, the second transition frame period, and the subsequent frame period, respectively. The preceding frame period F51 is a composite frame period. The first transition frame period F52, the second transition frame period F53, and the subsequent frame period F54 are normal frame periods. The scanning period of the preceding frame period F51, which is a composite frame period, is allocated the same proportion of illumination periods as the subsequent frame period F54. This scanning period is allocated more illumination periods than the first transition frame period F52 and the second transition frame period F53.

[0121] In a display device with a first mode and a second mode as operating modes, by using the first mode when displaying moving images and the second mode when displaying still images, the performance of displaying moving images can be improved, and power consumption can be reduced when displaying still images. However, when switching operating modes between a preceding frame period and a subsequent frame period, if the next subsequent frame period occurs after the preceding frame period, a suitable non-light-emitting period cannot be allocated to the subsequent frame period. Therefore, the display screen flickers when switching operating modes.

[0122] In contrast, in the display device of this embodiment, when switching operating modes between a preceding frame period and a subsequent frame period, two transition frame periods with a different proportion of light emission period than the preceding frame period are provided between the preceding frame period and the subsequent frame period. Therefore, by allocating the transition frame periods with a different proportion of light emission period than the preceding frame period, a suitable non-light emission period can be allocated to the subsequent frame period, thus preventing flickering when switching operating modes.

[0123] (Fourth implementation)

[0124] The display device of the fourth embodiment has the same configuration as the display device 10 of the first embodiment. Figure 1 The display device of this embodiment switches the operating mode between the first mode and the second mode described above. When switching the operating mode from the second mode to the first mode, the display device uses the same transmit start pulse (EMSP) as in the third embodiment. Figure 20 When switching the operating mode from mode 1 to mode 2, a different transmit initiation pulse (EMSP) is used than in the third embodiment.

[0125] Figure 23 This is a diagram showing the transmission start pulse (EMSP) of the display device in this embodiment when it switches the operating mode from mode 1 to mode 2. Figure 24 This is a diagram showing the luminescence state at this time. Figure 25 This is the timing diagram at this point. During frame periods F61 to F63, the transmit start pulse EMSP is as follows: Figure 23 and Figure 24 The display unit 11 changes as shown. Figure 24 The light-emitting part shown emits light, while other parts do not.

[0126] like Figure 23 As shown, frame period F61 is allocated a light emission period in the same way as frame period F14. The length of frame period F63 is 1.5 times the length of frame period F61. Two-thirds of frame period F63 is a scan period, and the remainder is a rest period. Frame period F63 is allocated a light emission period in the same way as frame period F44. A frame period F62 is set between frame period F61 and frame period F63. Frame period F62 is allocated a light emission period in the same way as frame period F22.

[0127] Frame periods F61 to F63 correspond to the preceding frame period, the transition frame period, and the subsequent frame period, respectively. The preceding frame period F61 and the transition frame period F62 are normal frame periods. The subsequent frame period F63 is a composite frame period. The scan period of the subsequent frame period F63, as a composite frame period, is allocated the same proportion of emission periods as the preceding frame period F61. This scan period is allocated the same number of emission periods as the transition frame period F62.

[0128] In the display device of this embodiment, similarly to the third embodiment, when switching the operating mode between the preceding frame period and the subsequent frame period, one or two transition frame periods with a different proportion of the light-emitting period than the preceding frame period are provided between the preceding frame period and the subsequent frame period. Therefore, by allocating the light-emitting period with a different proportion than the preceding frame period to the transition frame periods, a suitable non-light-emitting period can be allocated to the subsequent frame periods, and flickering during the switching of operating modes can be prevented.

[0129] (Fifth Embodiment)

[0130] The display device of the fifth embodiment has the same configuration as the display device 10 of the first embodiment. Figure 1 The display device of this embodiment switches the number of light emission times when switching frame rates. The display device of this embodiment has: a third mode, which operates normally at a frame rate of 120Hz and a light emission time of 1; and a fourth mode, which operates in a rest mode at a frame rate of 60Hz and a light emission time of 4. The display device of the fifth embodiment switches between the third mode and the fourth mode.

[0131] Figure 26 This is a diagram showing the transmission start pulse (EMSP) of the display device in this embodiment when it switches the operating mode from mode 3 to mode 4. Figure 27 This is a diagram showing the luminescence state at this time. Figure 28 This is the timing diagram at this point. During frame periods F71 to F73, the transmit start pulse EMSP is as follows: Figure 26 and Figure 27The display unit 11 changes as shown. Figure 27 The light-emitting part shown emits light, while other parts do not.

[0132] like Figure 26 As shown, frame period F71 is allocated a light emission period in the same way as frame period F14. The length of frame period F73 is twice the length of frame period F71. Half of frame period F73 is a scan period, and the remainder is a rest period. Frame period F73 is allocated four light emission periods and four non-light emission periods with a length Tx. A frame period F72 is set between frame period F71 and frame period F73. Frame period F72 is allocated a light emission period in the same way as frame period F22.

[0133] Frame periods F71 to F73 correspond to the preceding frame period, the transition frame period, and the subsequent frame period, respectively. The preceding frame period F71 and the transition frame period F72 are normal frame periods. The subsequent frame period F73 is a composite frame period. The scan period of the subsequent frame period F73, as a composite frame period, is allocated the same proportion of emission periods as the preceding frame period F71. This scan period is allocated the same number of emission periods as the transition frame period F72.

[0134] Figure 29 This is a diagram showing the transmission start pulse (EMSP) of the display device in this embodiment when it switches the operating mode from mode 4 to mode 3. Figure 30 This is a diagram showing the luminescence state at this time. Figure 31 This is the timing diagram at this point. During frame periods F81 to F84, the transmit start pulse EMSP is as follows: Figure 29 and Figure 30 The display unit 11 changes as shown. Figure 30 The light-emitting part shown emits light, while other parts do not.

[0135] like Figure 29 As shown, frame period F84 is allocated a light emission period in the same way as frame period F14. The length of frame period F81 is twice the length of frame period F84. Half of frame period F81 is a scan period, and the remainder is a rest period. Frame period F81 is allocated a light emission period in the same way as frame period F73. Two frame periods, F82 and F83, are set between frame periods F81 and F84. The light emission periods for frame periods F82 and F83 are set in the same way as for frame periods F12 and F13, respectively.

[0136] Frame periods F81 to F84 correspond to the preceding frame period, the first transition frame period, the second transition frame period, and the subsequent frame period, respectively. The preceding frame period F81 is a composite frame period. The first transition frame period F82, the second transition frame period F83, and the subsequent frame period F84 are normal frame periods. The scanning period of the preceding frame period F81, which is a composite frame period, is allocated the same proportion of illumination periods as the subsequent frame period F84. This scanning period is allocated more illumination periods than the first transition frame period F82 and the second transition frame period F83.

[0137] In the display device of this embodiment, similarly to the third and fourth embodiments, when switching the operating mode between the preceding frame period and the subsequent frame period, one or two transition frame periods with a different proportion of the light-emitting period than the preceding frame period are provided between the preceding frame period and the subsequent frame period. Therefore, by allocating the light-emitting period with a different proportion than the preceding frame period to the transition frame periods, a suitable non-light-emitting period can be allocated to the subsequent frame periods, and flickering during the switching of operating modes can be prevented.

[0138] The display device described above can be configured in various variations. For example, in a variation of the display device, three or more transition frame periods may be provided between the preceding frame period and the subsequent frame period. Although the more transition frame periods there are, the longer the time required to switch the number of light emission times, by allocating the light emission period to three or more transition frame periods, flickering when switching the number of light emission times for each frame period can be prevented more effectively.

[0139] The modified display device may also include an arbitrary pixel circuit capable of controlling the light emission state of the display elements. The modified display device may perform characteristic compensation of the driving elements internally or externally within the pixel circuit. The modified display device may also include an arbitrary light emission control line drive circuit that generates a signal applied to the light emission control line by sequentially delaying the provided control signals. The modified display device may also adjust the observed brightness by adjusting the power supply voltage, data voltage, input data, etc., in addition to switching the number of light emission cycles.

[0140] The above examples, as display devices incorporating pixel circuits containing light-emitting elements, illustrate an organic EL display device incorporating pixel circuits containing organic EL elements (organic light-emitting diodes). However, the same method can also be used to construct inorganic EL display devices incorporating pixel circuits containing inorganic light-emitting diodes, QLED (Quantum-dot Light Emitting Diode) display devices incorporating pixel circuits containing quantum dot light-emitting diodes, or LED display devices incorporating pixel circuits containing miniature LEDs or micro-LEDs. Furthermore, the features of the display devices described above can be arbitrarily combined without violating their properties to construct display devices that simultaneously possess the features of the above embodiments and variations.

[0141] Explanation of reference numerals in the attached figures

[0142] 10… Display devices

[0143] 11… Display Department

[0144] 12… Display control circuit

[0145] 13… Scan line drive circuit

[0146] 14…Data line driver circuit

[0147] 15…Light-emitting control line drive circuit

[0148] 20…pixel circuit

[0149] 30… unit circuit.

Claims

1. A display device, characterized in that, have: The display unit includes: multiple scan lines, multiple data lines, multiple light-emitting control lines, and multiple pixel circuits, each containing a light-emitting element; A scan line driving circuit that drives the aforementioned scan lines; A data line driver circuit that drives the aforementioned data lines; The light-emitting control line driving circuit drives the aforementioned light-emitting control line; and The display control circuit outputs a control signal to the aforementioned light-emitting control line drive circuit, indicating the light-emitting period allocated to the frame period. The aforementioned light-emitting control line driving circuit generates signals applied to the aforementioned light-emitting control lines by sequentially delaying the aforementioned control signals. When the ratio of the emission period to the emission period is the same between the preceding frame period and the subsequent frame period, but the number of emission periods is different, a transition frame period with a different ratio of emission period is set between the preceding frame period and the subsequent frame period. Between the aforementioned preceding frame period and the aforementioned subsequent frame period, as the aforementioned transition frame period, a first transition frame period and a second transition frame period with a different ratio of the emission period than the aforementioned first transition frame period are set.

2. The display device according to claim 1, characterized in that, The aforementioned transition frame period is allocated a light emission period with a start timing different from at least one of the aforementioned preceding frame period and the aforementioned subsequent frame period.

3. The display device according to claim 1, characterized in that, The aforementioned transition frame period is assigned a light emission period with an end timing different from at least one of the aforementioned preceding frame period and the aforementioned subsequent frame period.

4. The display device according to any one of claims 1 to 3, characterized in that, The aforementioned transition frame period is assigned a different emission period than the aforementioned preceding frame period and the aforementioned subsequent frame period.

5. The display device according to any one of claims 1 to 3, characterized in that, The aforementioned transition frame period is allocated the same number of emission periods as the aforementioned subsequent frame period.

6. The display device according to any one of claims 1 to 3, characterized in that, The subsequent frame period is allocated fewer light emission periods than the preceding frame period. The first transition frame period mentioned above is allocated a smaller number of light emission periods, but in a larger proportion, compared to the preceding frame period mentioned above. The second transition frame period mentioned above is allocated the same number of light emission periods as the first transition frame period mentioned above, but at a smaller proportion. The subsequent frame period is allocated the same number of light emission periods as the second transition frame period.

7. The display device according to any one of claims 1 to 3, characterized in that, The subsequent frame period is allocated a number of more light emission periods than the preceding frame period. The first transition frame period mentioned above is allocated a larger number of light emission periods compared to the preceding frame period, but at a smaller proportion. The second transition frame period mentioned above is allocated the same number of light emission periods as the first transition frame period mentioned above, but in a larger proportion. The subsequent frame period is allocated the same number of light emission periods as the second transition frame period.

8. The display device according to any one of claims 1 to 3, characterized in that, The second transition frame period is assigned a light emission period, at least one of the start timing and the end timing, which is different from the first transition frame period.

9. The display device according to claim 8, characterized in that, The subsequent frame period is allocated fewer light emission periods than the preceding frame period. The first transition frame period mentioned above is allocated a smaller number of light emission periods, but in a larger proportion, compared to the preceding frame period mentioned above. The second transition frame period mentioned above is allocated the same number of light emission periods as the first transition frame period mentioned above, but at a smaller proportion. The subsequent frame period is allocated the same number of light emission periods as the second transition frame period.

10. The display device according to any one of claims 1 to 3, characterized in that, The aforementioned preceding frame period is allocated two emission periods, and the aforementioned subsequent frame period is allocated one emission period.

11. The display device according to claim 8, characterized in that, The subsequent frame period is allocated a number of more light emission periods than the preceding frame period. The first transition frame period mentioned above is allocated a larger number of light emission periods compared to the preceding frame period, but at a smaller proportion. The second transition frame period mentioned above is allocated the same number of light emission periods as the first transition frame period mentioned above, but in a larger proportion. The subsequent frame period is allocated the same number of light emission periods as the second transition frame period.

12. The display device according to any one of claims 1 to 3, characterized in that, The aforementioned preceding frame period is allocated one emission period, and the aforementioned subsequent frame period is allocated two emission periods.

13. The display device according to any one of claims 1 to 3, characterized in that, One of the aforementioned preceding frame period and the aforementioned subsequent frame period is a typical frame period that only has a scan period. The other of the aforementioned preceding frame period and the aforementioned subsequent frame period is a composite frame period with a scan period and a rest period.

14. A display device, characterized in that, have: The display unit includes: multiple scan lines, multiple data lines, multiple light-emitting control lines, and multiple pixel circuits, each containing a light-emitting element; A scan line driving circuit that drives the aforementioned scan lines; A data line driver circuit that drives the aforementioned data lines; The light-emitting control line driving circuit drives the aforementioned light-emitting control line; and The display control circuit outputs a control signal to the aforementioned light-emitting control line drive circuit, indicating the light-emitting period allocated to the frame period. The aforementioned light-emitting control line driving circuit generates signals applied to the aforementioned light-emitting control lines by sequentially delaying the aforementioned control signals. When the ratio of the emission period to the emission period is the same between the preceding frame period and the subsequent frame period, but the number of emission periods is different, a transition frame period with a different ratio of emission period is set between the preceding frame period and the subsequent frame period. One of the aforementioned preceding frame period and the aforementioned subsequent frame period is a typical frame period that only has a scan period. The other of the aforementioned preceding frame period and the aforementioned subsequent frame period is a composite frame period that includes a scan period and a rest period. The scanning period during the aforementioned composite frame period is allocated the same proportion of the emission period as the aforementioned normal frame period.

15. A display device, characterized in that, have: The display unit includes: multiple scan lines, multiple data lines, multiple light-emitting control lines, and multiple pixel circuits, each containing a light-emitting element; A scan line driving circuit that drives the aforementioned scan lines; A data line driver circuit that drives the aforementioned data lines; The light-emitting control line driving circuit drives the aforementioned light-emitting control line; and The display control circuit outputs a control signal to the aforementioned light-emitting control line drive circuit, indicating the light-emitting period allocated to the frame period. The aforementioned light-emitting control line driving circuit generates signals applied to the aforementioned light-emitting control lines by sequentially delaying the aforementioned control signals. When the ratio of the emission period to the emission period is the same between the preceding frame period and the subsequent frame period, but the number of emission periods is different, a transition frame period with a different ratio of emission period is set between the preceding frame period and the subsequent frame period. One of the aforementioned preceding frame period and the aforementioned subsequent frame period is a typical frame period that only has a scan period. The other of the aforementioned preceding frame period and the aforementioned subsequent frame period is a composite frame period that includes a scan period and a rest period. The scanning period during the aforementioned composite frame period is allocated the same number of emission periods as the aforementioned transition frame period.

16. The display device according to claim 14, characterized in that, The scanning period during the aforementioned composite frame period is allocated the same number of emission periods as the aforementioned transition frame period.

17. A driving method for a display device, the display device having a display section, the display section comprising: a plurality of scan lines, a plurality of data lines, a plurality of light-emitting control lines, and a plurality of pixel circuits, each comprising a light-emitting element. The driving method for the above-mentioned display device is characterized by having: The steps to drive the above scan lines; The steps to drive the above data cable; The steps for driving the above-mentioned light-emitting control lines; and The step of outputting a control signal representing the emission period allocated to the frame period for driving the above-mentioned emission control line. The step of driving the light-emitting control line generates a signal applied to the light-emitting control line by sequentially delaying the control signals. When the ratio of the emission period to the emission period is the same between the preceding frame period and the subsequent frame period, but the number of emission periods is different, a transition frame period with a different ratio of emission period is set between the preceding frame period and the subsequent frame period. Between the aforementioned preceding frame period and the aforementioned subsequent frame period, as the aforementioned transition frame period, a first transition frame period and a second transition frame period with a different ratio of the emission period than the aforementioned first transition frame period are set.

Images