Display device and electronic apparatus

Abstract

To reduce discomfort to a user and to suppress deterioration in video quality of an original video.SOLUTION: A display device comprises: a first display panel; a second display panel; and a control device that transfers image data of a first frame to the first display panel, transfers the image data of a second frame to the second display panel, transfers the image data of a third frame to the first display panel, and transfers the image data of a fourth frame to the second display panel. The control device calculates a first differential value of the image data of the first frame and the image data of the second frame, and calculates a second differential value of the image data of the second frame and the image data of the third frame. When the first differential value is smaller than the second differential value, a transfer timing of the image data of the third frame is delayed by a first time period, and when the first differential value is larger than the second differential value, the image data of the fourth frame is delayed by the first time period.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a display device and an electronic device.

Background Art

[0002] Patent Document 1 discloses, as a technique particularly suitable for a head-mounted display, inputting a plurality of moving image data having arbitrary frame rates and performing a thinning process on the number of frames for each of the plurality of moving image data without changing the frame period.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Patent Document 1 describes, as one of the thinning processes, thinning odd frames for the moving image data for the left eye and thinning even frames for the moving image data for the right eye. In this case, since images of completely different frames are projected onto the left and right eyes, the greater the difference in the images projected onto the left and right eyes, the more discomfort is given to the user.

[0005] Further, Patent Document 1 describes, as another thinning process, thinning one of the odd frames and the even frames for both the moving image data for the left eye and the moving image data for the right eye. In this case, images of the same frame are projected onto the left and right eyes, but since the frames are thinned, the video quality deteriorates with respect to the original video.

Means for Solving the Problems

[0006] The display device according to one aspect of the present invention includes a first display panel, a second display panel, and a control device that transfers the image data of the first frame to the first display panel, transfers the image data of the second frame following the first frame to the second display panel, transfers the image data of the third frame following the second frame to the first display panel, and transfers the image data of the fourth frame following the third frame to the second display panel. The control device calculates a first difference value between the image data of the first frame and the image data of the second frame, calculates a second difference value between the image data of the second frame and the image data of the third frame, and when the first difference value is smaller than the second difference value, delays the transfer timing of the image data of the third frame by a first time, and when the first difference value is larger than the second difference value, delays the transfer timing of the image data of the fourth frame by the first time.

[0007] An electronic device according to one aspect of the present invention includes the display device according to the above aspect.

Brief Description of Drawings

[0008]

Figure 1

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Figure 4

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Figure 11

Embodiments for Carrying Out the Invention

[0009] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. Here, in each of the following figures, the scales of each member may be different from the actual ones in order to make each member recognizable.

[0010] 1. Electronic device In the present embodiment, as the electronic device of the present disclosure, an example is a see-through type head-mounted display 100 that can view both a video and the scenery in front of the eyes. In the following description, the head-mounted display 100 may be abbreviated as "HMD100".

[0011] FIG. 1 is a diagram showing a state in which the HMD100 is worn on the user M. As shown in FIG. 1, the HMD100 is worn on the head of the user M like glasses. The HMD100 communicates with a video supply device (not shown) via a communication cable 150. For example, examples of the video supply device include a personal computer, a DVD (Digital Versatile Disc) player, a smartphone, and a tablet terminal.

[0012] The HMD100 receives a video signal from a video supply device via a communication cable 150. For example, the communication cable 150 is an HDMI cable that transmits a video signal according to the HDMI (High-Definition Multimedia Interface: registered trademark) standard. Alternatively, the communication cable 150 may be a USB cable that transmits a video signal according to the USB (Universal Serial Bus) Type-C standard. As described above, by using the communication cable 150 capable of supplying DC voltage along with the transmission of the video signal, it is not necessary to incorporate a battery in the HMD100, so the weight reduction of the HMD100 can be achieved.

[0013] Based on the video signal supplied from the video supply device via the communication cable 150, the HMD100 forms a virtual image recognized as a video by the user M. Also, the HMD100 allows the user M to visually recognize the scenery in front by guiding external light to the user M's eyeballs.

[0014] FIG. 2 is a perspective view of the HMD100. As shown in FIG. 2, the HMD100 includes a frame 120 having a shape like glasses and an optical module 111 incorporated inside the frame 120. The optical module 111 may sometimes be called an optical engine module.

[0015] The frame 120 includes a pair of temple parts 122A and 122B for hanging the HMD100 on the ears of the user M. The optical module 111 includes a first optical module 111A for the left eye and a second optical module 111B for the right eye. The communication cable 150 is connected to the first optical module 111A. Based on the video signal supplied from the video supply device via the communication cable 150, the first optical module 111A forms a virtual image for the left eye recognized as a video by the user M.

[0016] For example, the first optical module 111A is communicably connected to the second optical module 111B via an FPC (Flexible Printed Circuit) cable (not shown). The first optical module 111A transmits a control signal to the second optical module 111B so that a virtual image for the right eye is formed in synchronization with the virtual image for the left eye. The second optical module 111B forms a virtual image for the right eye that is recognized as an image by the user M based on the control signal transmitted from the first optical module 111A.

[0017] The first optical module 111A and the second optical module 111B have substantially the same configuration, and each component of both is arranged symmetrically left and right. Therefore, hereinafter, the configuration of the optical module 111 will be described using the first optical module 111A as a representative.

[0018] 2. Optical Module FIG. 3 is a plan view showing an example of the schematic configuration of the first optical module 111A. In FIG. 3, the XYZ axes are set as coordinate axes orthogonal to each other, the direction indicated by each arrow along the axis is the + direction, and the direction opposite to the + direction is the - direction.

[0019] The X direction corresponds to the front-rear direction of the user M wearing the HMD 100. The Y direction corresponds to the left-right direction of the user M. The Z direction corresponds to the up-down direction of the user M. In the present embodiment, the -Y direction may be referred to as the left side, the +Y direction as the right side, the +X direction as the front side, and the -X direction as the rear side. Further, viewing from the +Z direction is referred to as a plan view or planar.

[0020] As shown in FIG. 3, the first optical module 111A includes a display panel 11, a projection optical system 15, and a light guide device 20. For example, the display panel 11 is a self-emitting electro-optical device. A self-emitting electro-optical device is a device that generates light by itself using electrical energy supplied from the outside without requiring a light source such as a backlight. As an example, the display panel 11 is an OLED panel including an OLED as a light emitting element.

[0021] The display panel 11 displays an image based on the image data transferred from the control device 12 described later, and emits image light G corresponding to the image to the projection optical system 15. In FIG. 3, the display panel 11 is arranged in a state perpendicular to the XY plane, but this arrangement is merely an example, and how to arrange the display panel 11 in the first optical module 111A can be appropriately determined according to the structural constraints of the first optical module 111A.

[0022] The projection optical system 15 projects the image light G emitted from the display panel 11 onto the incident portion 22 of the light guide device 20. In FIG. 3, the projection optical system 15 composed of a single lens is illustrated, but the projection optical system 15 may be composed of a plurality of optical elements such as lenses and mirrors.

[0023] The light guide device 20 guides the image light G projected from the projection optical system 15 to a predetermined position and emits it as virtual image light from the predetermined position. As will be described later, for example, the predetermined position is the position where the light extraction unit 31 is arranged. The light guide device 20 emits the image light G projected from the projection optical system 15 as virtual image light toward the left eye ME of the user M and transmits the external light SL incident from the outside. The light guide device 20 includes a light guide 21, an incident portion 22, and a light extraction unit 31.

[0024] The light guide 21 is composed of a plate-shaped light guide member having light transmissivity. The incident portion 22 is composed of a triangular prism-shaped member having light transmissivity. For example, the light guide 21 and the incident portion 22 are composed of glass, plastic, or the like. In the present embodiment, the refractive indices of the light guide 21 and the incident portion 22 are substantially equal.

[0025] The incident portion 22 has a light incident surface 22a that captures the image light G projected from the projection optical system 15, and a reflection surface 22b that reflects the captured image light G and guides it into the interior of the light guide 21. For example, the reflection surface 22b is formed by depositing an aluminum vapor deposition film on the surface of a prism shape, reflects the incident image light G, and bends its optical path toward the interior of the light guide 21. Thereby, the image light G enters the light guide 21 from the incident portion 22.

[0026] The light guide 21 extends in the left - right direction of the user M, that is, in the Y direction. The light guide 21 is arranged so as to be inclined with respect to the optical axis AX passing through the center of the exit pupil SM. Specifically, the light guide 21 is inclined such that the left - hand end of the light guide 21 is located on the rear side with respect to the right - hand end of the light guide 21. In other words, the light guide 21 is inclined so as to approach the face of the user M as it goes toward the left side of the user M. The position of the exit pupil SM corresponds to the position of the left eye ME of the user M.

[0027] The light guide 21 has a pair of first surface 21a and second surface 21b that are parallel to each other. Since the first surface 21a and the second surface 21b are parallel planes, they do not cause magnification or focus deviation with respect to external light SL. The first surface 21a and the second surface 21b function as total reflection surfaces that totally reflect the image light G propagating inside the light guide 21, and guide the image light G to the light extraction unit 31 with little loss.

[0028] The image light G incident on the light guide 21 is totally reflected by entering the first surface 21a. Then, the image light G enters the second surface 21b and is totally reflected. The image light G is totally reflected one or more times between the first surface 21a and the second surface 21b, and propagates from the left side to the right side inside the light guide 21 and reaches the light extraction unit 31.

[0029] The light extraction unit 31 is disposed on the first surface 21a of the light guide 21, and extracts the image light G from the light guide 21 toward the exit pupil SM. The light extraction unit 31 is composed of a plate-like member extending along the first surface 21a of the light guide 21. The light extraction unit 31 includes a transparent member 31a and a plurality of half mirrors 31b embedded inside the transparent member 31a. The refractive index of the transparent member 31a is substantially equal to the refractive index of the light guide 21. Thereby, reflection of the image light G at the interface between the light extraction unit 31 and the light guide 21 is suppressed.

[0030] Each half mirror 31b extends in the Z direction and is arranged at a predetermined pitch inside the transparent member 31a. Each half mirror 31b is arranged so as to be inclined with respect to the optical axis AX. Specifically, the half mirror 31b is inclined such that the rear end portion 31b1 of the half mirror 31b is located on the right side of the front end portion 31b2 of the half mirror 31b. The first edge 33 and the second edge 34 located at both ends of the light extraction unit 31 are formed to be parallel to the half mirror 31b.

[0031] The image light G propagating inside the light guide 21 is reflected by the half mirror 31b at a predetermined angle, and is emitted as a parallel light beam from the light extraction unit 31 toward the exit pupil SM. The image light G emitted from the light extraction unit 31 enters the left eye ME of the user M as virtual image light and forms an image on the retina of the left eye ME. In this way, when the image light G forms an image on the retina of the left eye ME, the virtual image formed by the first optical module 111A is recognized by the user M as a video.

[0032] In addition, the external light SL incident on the second surface 21b of the light guide 21 passes through the inside of the light guide 21 and is emitted from the first surface 21a of the light guide 21 toward the exit pupil SM. The external light SL emitted from the first surface 21a of the light guide 21 enters the left eye ME of the user M and forms an image on the retina of the left eye ME. In this way, when the external light SL forms an image on the retina of the left eye ME, the user M can visually recognize the external world, that is, the scenery in front of him / her, in a see-through manner.

[0033] As described above, the user M wearing the HMD 100 equipped with the optical module 111 can view both the video based on the video signal supplied from the video supply device and the scenery in front of him / her. Note that the configuration of the light guide device 20 described in this embodiment is merely an example, and for example, the configuration described in Japanese Unexamined Patent Application Publication No. 2015-72438 may be adopted as the configuration of the light guide device 20.

[0034] In the following description, the display panel 11 provided in the first optical module 111A may be referred to as the "first display panel 11L", and the display panel 11 provided in the second optical module 111B may be referred to as the "second display panel 11R". Further, when it is not necessary to distinguish between the first display panel 11L and the second display panel 11R, the first display panel 11L and the second display panel 11R are collectively referred to as the "display panel 11".

[0035] 3. Display Device The HMD 100 includes a display device 10. FIG. 4 is a block diagram showing an example of the schematic configuration of the display device 10. As shown in FIG. 4, the display device 10 includes a first display panel 11L, a second display panel 11R, and a control device 12. As already described, for example, the first display panel 11L and the second display panel 11R are OLED panels and are electrically connected to the control device 12 via an FPC cable (not shown).

[0036] FIG. 5 is a plan view showing an example of the schematic configuration of the display panel 11. As shown in FIG. 5, the display panel 11 includes a plurality of pixels 40, two drive circuits 50, and a plurality of mounting terminals 60. The pixels 40 and the drive circuits 50 are arranged in the circuit region W1, and the mounting terminals 60 are arranged in the mounting region W2.

[0037] The plurality of pixels 40 are arranged in a matrix in the display region W3 included in the circuit region W1. Each of the plurality of pixels 40 includes a red pixel 40R, a green pixel 40G, and a blue pixel 40B as sub-pixels. The red pixel 40R emits red light. The green pixel 40G emits green light. The blue pixel 40B emits blue light.

[0038] The two drive circuits 50 are arranged outside the display area W3 in the circuit area W1. In the following description, one of the two drive circuits 50 may be referred to as the "first drive circuit 51", and the other of the two drive circuits 50 may be referred to as the "second drive circuit 52". The first drive circuit 51 is arranged on the left side of the display area W3. The second drive circuit 52 is arranged on the lower side of the display area W3.

[0039] In the circuit area W1, a plurality of scan lines 71 extending in the horizontal direction of the display panel 11, a plurality of control lines 72 extending in the horizontal direction corresponding to each scan line 71, and a plurality of data lines 73 extending in the vertical direction of the display panel 11 are arranged. The first drive circuit 51 is electrically connected to each scan line 71 and each control line 72. The second drive circuit 52 is electrically connected to each data line 73.

[0040] Each mounting terminal 60 is electrically connected to the control device 12 via an FPC cable (not shown). The first control signal, the second control signal, the power supply voltage, and the common voltage output from the control device 12 are input to the display panel 11 via the corresponding mounting terminals 60. The first control signal is a signal for controlling the operation of the first drive circuit 51. The second control signal is a signal for controlling the operation of the second drive circuit 52. The power supply voltage and the common voltage are voltages used to supply a drive current to the light-emitting element 44 described later.

[0041] The first drive circuit 51 operates according to the first control signal supplied from the control device 12 via the mounting terminal 60, and applies a predetermined voltage to each scan line 71 and each control line 72 at a predetermined timing. The second drive circuit 52 operates according to the second control signal supplied from the control device 12 via the mounting terminal 60, and applies a predetermined voltage to each data line 73 at a predetermined timing.

[0042] FIG. 6 is an equivalent circuit diagram showing an example of the schematic configuration of the pixel circuit included in the red pixel 40R. Note that the configuration of the pixel circuits included in the green pixel 40G and the blue pixel 40B is the same as the circuit configuration shown in FIG. 6.

[0043] As shown in FIG. 6, the pixel circuit of the red pixel 40R includes a selection transistor 41, a driving transistor 42, a light emission control transistor 43, a light emitting element 44, and a holding capacitor 45. For example, the selection transistor 41, the driving transistor 42, and the light emission control transistor 43 are each a P-channel type TFT (Thin Film Transistor).

[0044] The gate electrode of the selection transistor 41 is electrically connected to the scanning line 71. The gate electrode of the driving transistor 42 is electrically connected to the data line 73 via the source region and the drain region of the selection transistor 41. The gate electrode of the light emission control transistor 43 is electrically connected to the control line 72.

[0045] The light emitting element 44 is a light emitting element that emits red light. For example, the light emitting element 44 is an OLED having a structure in which a light emitting layer is sandwiched between an anode and a cathode. The pixel circuit of the green pixel 40G includes a light emitting element 44 that emits green light. The pixel circuit of the blue pixel 40B includes a light emitting element 44 that emits blue light.

[0046] [[ID=1,4]] The anode of the light emitting element 44 is electrically connected to the power supply wiring 81 via the source region and the drain region of the driving transistor 42 and the source region and the drain region of the light emission control transistor 43. The cathode of the light emitting element 44 is electrically connected to the common wiring 82. A power supply voltage supplied from the control device 12 is applied to the power supply wiring 81 via the mounting terminal 60. A common voltage supplied from the control device 12 is applied to the common wiring 82 via the mounting terminal 60.

[0047] The holding capacitor 45 is a capacitor for holding the gate voltage of the driving transistor 42. One electrode of the holding capacitor 45 is electrically connected to the gate electrode of the driving transistor 42. The other electrode of the holding capacitor 45 is electrically connected to the power supply wiring 81. Note that, as the holding capacitor 45, a capacitor parasitic on the gate electrode of the driving transistor 42 may be used. Alternatively, as the holding capacitor 45, a capacitor formed by sandwiching an insulating layer with different conductive layers in the silicon substrate constituting the display panel 11 may be used.

[0048] In the pixel circuit configured as described above, when the voltage applied to the scanning line 71 is at a high level, the selection transistor 41 is in an off state. On the other hand, when the voltage applied to the scanning line 71 is at a low level, the selection transistor 41 is in an on state. When the selection transistor 41 is in an on state, the holding capacitor 45 is charged by the potential difference between the data line 73 and the power supply wiring 81.

[0049] When the voltage applied to the control line 72 is at a high level, the light emission control transistor 43 is in an off state. When the light emission control transistor 43 is in an off state, the anode of the light emitting element 44 is electrically disconnected from the driving transistor 42, so no driving current flows through the light emitting element 44. That is, when the light emission control transistor 43 is in an off state, the light emitting element 44 does not emit light.

[0050] On the other hand, when the voltage applied to the control line 72 is at a low level, the light emission control transistor 43 is in an on state. When the light emission control transistor 43 is in an on state, a driving current flows through the light emitting element 44 via the driving transistor 42, so the light emitting element 44 emits light. When the light emitting element 44 emits light, the red pixel 40R emits light, and red light is emitted from the red pixel 40R.

[0051] The drive current flowing through the light-emitting element 44 depends on the gate voltage of the drive transistor 42. The gate voltage of the drive transistor 42 is equal to the voltage held by the holding capacitor 45. Therefore, a drive current having a current value corresponding to the voltage held by the holding capacitor 45 flows through the light-emitting element 44.

[0052] The emission luminance of the light-emitting element 44 depends on the value of the drive current and the emission period of the light-emitting element 44. The value of the drive current can be controlled by adjusting the voltage applied to the data line 73. The emission period of the light-emitting element 44 can be controlled by adjusting the period during which the emission control transistor 43 is in the on state, that is, the period during which the voltage applied to the control line 72 is at a low level. In other words, the brightness of the red pixel 40R can be controlled by adjusting the voltage applied to the data line 73 and the period during which the voltage applied to the control line 72 is at a low level. The same applies to the brightness of the green pixel 40G and the blue pixel 40B.

[0053] Hereinafter, the description will continue by referring back to FIG. 4. As shown in FIG. 4, the control device 12 includes a video receiving unit 210, a frame buffer 220, a frame comparison unit 230, a timing generation unit 240, and an image distribution unit 250. The control device 12 transfers the image data of one of the odd frames and the even frames to the first display panel 11L, and transfers the image data of the other of the odd frames and the even frames to the second display panel 11R.

[0054] The video receiving unit 210 receives a video signal supplied from a video supply device and acquires image data from the video signal. The video receiving unit 210 outputs the image data acquired from the video signal to the frame buffer 220.

[0055] The frame buffer 220 holds the image data input from the video receiving unit 210 in units of one frame. The frame buffer 220 preferably has a storage capacity capable of holding at least three frames of image data and absorbing the delay generated due to each of the processes described later. Each of the processes described later includes a process of comparing the image data between adjacent frames, a process of generating the transfer timing of the image data, and a process of transferring the image data.

[0056] The frame comparison unit 230 calculates the difference value of the image data between two consecutive frames based on the image data held in the frame buffer 220. As a method for calculating the difference value of the image data between two consecutive frames, a generally known image comparison method may be adopted. The frame comparison unit 230 outputs the calculation result of the difference value to the timing generation unit 240.

[0057] The timing generation unit 240 generates the transfer timing of the image data held in the frame buffer 220 based on the calculation result of the difference value obtained from the frame comparison unit 230. The timing generation unit 240 executes the timing generation process shown in the flowchart of FIG. 7 in order to generate the transfer timing of the image data. The details of the timing generation process executed by the timing generation unit 240 will be described later.

[0058] The image distribution unit 250 transfers the image data held in the frame buffer 220 to the first display panel 11L and the second display panel 11R alternately in units of frames based on the transfer timing generated by the timing generation unit 240. In the present embodiment, the image distribution unit 250 transfers the image data of odd frames to the first display panel 11L and the image data of even frames to the second display panel 11R. Note that the present invention is not limited to this, and the image data of either odd frames or even frames may be transferred to the first display panel 11L, and the image data of the other of odd frames and even frames may be transferred to the second display panel 11R. That is, the image data of even frames may be transferred to the first display panel 11L, and the image data of odd frames may be transferred to the second display panel 11R.

[0059] Note that the first display panel 11L and the second display panel 11R do not update the display image until they receive an update instruction from the image distribution unit 250. Further, when the first display panel 11L and the second display panel 11R receive an update instruction from the image distribution unit 250 and have not received the image data for one frame, they update the display image based on the received image data.

[0060] Part or all of the functions of the control device 12 configured as described above may be configured by a processor such as a CPU (Central Processing Unit) or a GPU (Graphics Processing Unit). Further, part or all of the functions of the control device 10 may be configured by circuits such as a DSP (Digital Signal Processor), an ASIC (Application Specific Integrated Circuit), a PLD (Programmable Logic Device), and an FPGA (Field Programmable Gate Array).

[0061] FIG. 7 is a flowchart showing the timing generation process executed by the timing generation unit 240 of the control device 12. As shown in FIG. 7, the timing generation unit 240 acquires the difference value of the image data between two consecutive frames from the frame comparison unit 230 (step S1). Then, the timing generation unit 240 determines whether the number of difference values acquired from the frame comparison unit 230 is two or more (step S2).

[0062] When the timing generation unit 240 determines that the number of difference values acquired from the frame comparison unit 230 is less than two (step S2: NO), it returns to the process of step S1. On the other hand, when the timing generation unit 240 determines that the number of difference values acquired from the frame comparison unit 230 is two or more (step S2: YES), it proceeds to the process of step S3 described later.

[0063] When the timing generation unit 240 proceeds to the process of step S3, it acquires a difference value D(m) between the image data of the n-th frame and the image data of the (n + 1)-th frame (step S3). Here, n is a variable indicating the order of the frames and is an integer of 1 or more. Also, m is a variable indicating the order of the difference values acquired from the frame comparison unit 230 and is an integer of 1 or more. For example, when the value of the variable m is 1, the difference value D(1) indicates the difference value between the image data of the first frame and the image data of the second frame. When the value of the variable m is 2, the difference value D(2) indicates the difference value between the image data of the second frame and the image data of the third frame. The n-th frame in the present embodiment corresponds to the "first frame" in the claims, the (n + 1)-th frame corresponds to the "second frame" in the claims, the (n + 2)-th frame corresponds to the "third frame" in the claims, and the (n + 3)-th frame corresponds to the "fourth frame" in the claims. The n-th frame may be, for example, an odd-numbered frame. In this case, the image data of the n-th frame and the (n + 2)-th frame may be transferred to the first display panel 11L, and the image data of the (n + 1)-th frame and the (n + 3)-th frame may be transferred to the second display panel 11R. Also, the n-th frame may be an even-numbered frame. In this case, the image data of the n-th frame and the (n + 2)-th frame may be transferred to the second display panel 11R, and the image data of the (n + 1)-th frame and the (n + 3)-th frame may be transferred to the first display panel 11L.

[0064] Then, the timing generation unit 240 determines whether the difference value D(m) is equal to the difference value D(m + 1) (step S4). For example, when the value of the variable m is 1, the timing generation unit 240 determines whether the difference value D(1) between the image data of the first frame and the image data of the second frame is equal to the difference value D(2) between the image data of the second frame and the image data of the third frame.

[0065] When the timing generation unit 240 determines that the difference value D(m) is equal to the difference value D(m + 1) (step S4: YES), it skips the processes of steps S5, S6, and S7 and proceeds to the process of step S8. On the other hand, when the timing generation unit 240 determines that the difference value D(m) is not equal to the difference value D(m + 1) (step S4: NO), it proceeds to the process of step S5 described below.

[0066] When the timing generation unit 240 proceeds to the process of step S5, it determines whether the difference value D(m) is smaller than the difference value D(m + 1) (step S5). For example, when the value of the variable m is 1, the timing generation unit 240 determines whether the difference value D(1) between the image data of the first frame and the image data of the second frame is smaller than the difference value D(2) between the image data of the second frame and the image data of the third frame.

[0067] When the timing generation unit 240 determines that the difference value D(m) is smaller than the difference value D(m + 1) (step S5: YES), it delays the transfer timing of the image data of the (n + 2)-th frame by the first time ΔT (step S6). As an example, the first time ΔT is half the time of one frame. For example, when the value of the variable m is 1, the timing generation unit 240 delays the transfer timing of the image data of the third frame by the first time ΔT. After the timing generation unit 240 finishes the process of step S6, it proceeds to the process of step S8.

[0068] On the other hand, when the timing generation unit 240 determines that the difference value D(m) is larger than the difference value D(m + 1) (step S5: NO), it delays the transfer timing of the image data of the (n + 3)-th frame by the first time ΔT (step S7). For example, when the value of the variable m is 1, the timing generation unit 240 delays the transfer timing of the image data of the fourth frame by the first time ΔT. After the timing generation unit 240 finishes the process of step S7, it proceeds to the process of step S8.

[0069] When the timing generation unit 240 proceeds to the process of step S8, it adds 1 to the value of the variable m (step S8). After the timing generation unit 240 finishes the process of step S8, it returns to the process of step S3.

[0070] The above is the description of the timing generation process executed by the timing generation unit 240 of the control device 12. Below, the operation of the control device 12 will be described in more detail with specific examples. In the following description, for example, "image data of the first frame" may be abbreviated as "first frame data". Other similar terms may also be abbreviated in the same way.

[0071] FIG. 8 is a first image diagram showing the temporal correspondence relationship among the frame data capture timing FT, the first video P1 which is the video displayed on the first display panel 11L, and the second video P2 which is the video displayed on the second display panel 11R. The first video P1 is a video based on the image data of odd frames transferred to the first display panel 11L and is the video projected onto the left eye of the user M. The second video P2 is a video based on the image data of even frames transferred to the second display panel 11R and is the video projected onto the right eye of the user M.

[0072] In FIG. 8, the numbers from 1 to 7 represent frame numbers. In FIG. 8, the time t1 is the timing at which the capture of the first frame data among the image data included in the video signal input to the control device 12 is completed. In other words, the time t1 is the timing at which all of the first frame data is held in the frame buffer 220.

[0073] Time t2 is the timing at which the capture of the second frame data among the image data included in the video signal is completed. Time t3 is the timing at which the capture of the third frame data among the image data included in the video signal is completed. Time t4 is the timing at which the capture of the fourth frame data among the image data included in the video signal is completed. Time t5 is the timing at which the capture of the fifth frame data among the image data included in the video signal is completed. Time t6 is the timing at which the capture of the sixth frame data among the image data included in the video signal is completed.

[0074] When the capture of the first frame data is completed at time t1, the control device 12 transfers the first frame data to the first display panel 11L. As a result, the first video P1 based on the first frame data is displayed on the first display panel 11L from time t1.

[0075] When the capture of the second frame data is completed at time t2, the control device 12 transfers the second frame data to the second display panel 11R. As a result, the second video P2 based on the second frame data is displayed on the second display panel 11R from time t2.

[0076] When the capture of the third frame data is completed at time t3, the control device 12 determines the magnitude relationship between the difference value D(1) between the first frame data and the second frame data and the difference value D(2) between the second frame data and the third frame data. Here, although not shown in FIG. 8, when the control device 12 determines that the difference value D(1) is equal to the difference value D(2), the control device 12 transfers the third frame data to the first display panel 11L at time t3.

[0077] On the one hand, as shown in FIG. 8, when the control device 12 determines that the difference value D(1) is smaller than the difference value D(2), it transfers the third frame data to the first display panel 11L at a time t3' that is delayed by the first time ΔT from the time t3. As already described, the first time ΔT is half the time of one frame. As a result, the first video P1 based on the third frame data is displayed on the first display panel 11L from the time t3'.

[0078] When the control device 12 finishes capturing the fourth frame data at the time t4, it determines the magnitude relationship between the difference value D(2) between the second frame data and the third frame data and the difference value D(3) between the third frame data and the fourth frame data. Here, when the control device 12 determines that the difference value D(2) is equal to the difference value D(3), it transfers the fourth frame data to the second display panel 11R at the time t4. As a result, the second video P2 based on the fourth frame data is displayed on the second display panel 11R from the time t4.

[0079] When the control device 12 finishes capturing the fifth frame data at the time t5, it determines the magnitude relationship between the difference value D(3) between the third frame data and the fourth frame data and the difference value D(4) between the fourth frame data and the fifth frame data. Here, when the control device 12 determines that the difference value D(3) is equal to the difference value D(4), it transfers the fifth frame data to the first display panel 11L at the time t5. As a result, the first video P1 based on the fifth frame data is displayed on the first display panel 11L from the time t5.

[0080] When the control device 12 finishes capturing the sixth frame data at time t6, it determines the magnitude relationship between the difference value D(4) between the fourth frame data and the fifth frame data and the difference value D(5) between the fifth frame data and the sixth frame data. Here, when the control device 12 determines that the difference value D(4) is equal to the difference value D(5), it transfers the sixth frame data to the second display panel 11R at time t6. As a result, a second video P2 based on the sixth frame data is displayed on the second display panel 11R from time t6.

[0081] As described above, when the difference value D(1) between the first frame data and the second frame data is smaller than the difference value D(2) between the second frame data and the third frame data, the control device 12 delays the transfer timing of the third frame data by the first time ΔT. In this case, the time during which the first video P1 based on the first frame data and the second video P2 based on the second frame data are displayed simultaneously becomes longer by the first time ΔT. That is, the time during which the highly similar first video P1 and second video P2 are displayed simultaneously becomes longer by the first time ΔT.

[0082] On the other hand, the time during which the second video P2 based on the second frame data and the first video P1 based on the third frame data are displayed simultaneously becomes shorter by the first time ΔT. That is, the time during which the less similar first video P1 and second video P2 are displayed simultaneously becomes shorter by the first time ΔT.

[0083] FIG. 9 is a second image diagram showing the temporal correspondence relationship between the frame data capture timing FT, the first video P1 that is the video displayed on the first display panel 11L, and the second video P2 that is the video displayed on the second display panel 11R.

[0084] When the control device 12 finishes capturing the first frame data at time t1, it transfers the first frame data to the first display panel 11L. As a result, a first video P1 based on the first frame data is displayed on the first display panel 11L from time t1.

[0085] When the capture of the second frame data is completed at time t2, the control device 12 transfers the second frame data to the second display panel 11R. As a result, a second video P2 based on the second frame data is displayed on the second display panel 11R from time t2.

[0086] When the capture of the third frame data is completed at time t3, the control device 12 determines the magnitude relationship between the difference value D(1) between the first frame data and the second frame data and the difference value D(2) between the second frame data and the third frame data. Here, when the control device 12 determines that the difference value D(1) is larger than the difference value D(2), the control device 12 transfers the third frame data to the first display panel 11L at time t3 and determines to delay the transfer timing of the fourth frame data by the first time ΔT. As a result, a first video P1 based on the third frame data is displayed on the first display panel 11L from time t3.

[0087] When the capture of the fourth frame data is completed at time t4, the control device 12 determines the magnitude relationship between the difference value D(2) between the second frame data and the third frame data and the difference value D(3) between the third frame data and the fourth frame data. However, as described above, since it has already been determined to delay the transfer timing of the fourth frame data by the first time ΔT, the control device 12 transfers the fourth frame data to the second display panel 11R at time t4' which is delayed by the first time ΔT from time t4 regardless of the determination result. As a result, a second video P2 based on the fourth frame data is displayed on the second display panel 11R from time t4'. The operations after time t5 are the same as the operations described with reference to FIG. 8.

[0088] As described above, when the difference value D(1) between the first frame data and the second frame data is greater than the difference value D(2) between the second frame data and the third frame data, the control device 12 delays the transfer timing of the fourth frame data by the first time ΔT. In this case, the time during which the second video P2 based on the second frame data and the third video P3 based on the third frame data are simultaneously displayed becomes longer by the first time ΔT. That is, the time during which the first video P1 and the second video P2 with high similarity are simultaneously displayed becomes longer by the first time ΔT.

[0089] On the other hand, the time during which the first video P1 based on the third frame data and the second video P2 based on the fourth frame data are simultaneously displayed becomes shorter by the first time ΔT. That is, the time during which the first video P1 and the second video P2 with low similarity are simultaneously displayed becomes shorter by the first time ΔT.

[0090] FIG. 10 is a third image diagram showing the temporal correspondence relationship between the frame data capture timing FT, the first video P1 that is the video displayed on the first display panel 11L, and the second video P2 that is the video displayed on the second display panel 11R.

[0091] When the capture of the first frame data is completed at time t1, the control device 12 transfers the first frame data to the first display panel 11L. As a result, the first video P1 based on the first frame data is displayed on the first display panel 11L from time t1.

[0092] When the capture of the second frame data is completed at time t2, the control device 12 transfers the second frame data to the second display panel 11R. As a result, the second video P2 based on the second frame data is displayed on the second display panel 11R from time t2.

[0093] When the control device 12 finishes capturing the third frame data at time t3, it determines the magnitude relationship between the difference value D(1) between the first frame data and the second frame data and the difference value D(2) between the second frame data and the third frame data. Here, when the control device 12 determines that the difference value D(1) is smaller than the difference value D(2), it transfers the third frame data to the first display panel 11L at time t3' which is delayed by the first time ΔT from time t3. As a result, the first video P1 based on the third frame data is displayed on the first display panel 11L from time t3'.

[0094] When the control device 12 finishes capturing the fourth frame data at time t4, it determines the magnitude relationship between the difference value D(2) between the second frame data and the third frame data and the difference value D(3) between the third frame data and the fourth frame data. Here, when the control device 12 determines that the difference value D(2) is larger than the difference value D(3), it transfers the fourth frame data to the second display panel 11R at time t4 and determines to delay the transfer timing of the fifth frame data by the first time ΔT. As a result, the second video P2 based on the fourth frame data is displayed on the second display panel 11R from time t4.

[0095] When the control device 12 finishes capturing the fifth frame data at time t5, it determines the magnitude relationship between the difference value D(3) between the third frame data and the fourth frame data and the difference value D(4) between the fourth frame data and the fifth frame data. However, as described above, since it has already been determined to delay the transfer timing of the fifth frame data by the first time ΔT, the control device 12 transfers the fifth frame data to the first display panel 11L at time t5' which is delayed by the first time ΔT from time t5 regardless of the determination result. As a result, the second video P2 based on the fifth frame data is displayed on the first display panel 11L from time t5'. The operations after time t6 are the same as the operations described with reference to FIG. 8.

[0096] As described above, in the example shown in FIG. 10, the time during which the first video P1 based on the first frame data and the second video P2 based on the second frame data are simultaneously displayed becomes longer by the first time ΔT, and the time during which the first video P1 based on the third frame data and the second video P2 based on the fourth frame data are simultaneously displayed also becomes longer by the first time ΔT.

[0097] Also, in the example shown in FIG. 10, the time during which the second video P2 based on the second frame data and the first video P1 based on the third frame data are simultaneously displayed becomes shorter by the first time ΔT, and the time during which the second video P2 based on the fourth frame data and the first video P1 based on the fifth frame data are simultaneously displayed becomes shorter by the first time ΔT.

[0098] As described with reference to FIGS. 8 to 10, according to the present embodiment, the time during which the first video P1 and the second video P2 with low similarity are simultaneously displayed, that is, the time during which two videos with low similarity are simultaneously projected onto the left and right eyes of the user M, becomes shorter by the first time ΔT, so that the sense of discomfort given to the user can be reduced. Also, according to the present embodiment, the time during which the first video P1 and the second video P2 with high similarity are simultaneously displayed, that is, the time during which two videos with high similarity are simultaneously projected onto the left and right eyes of the user M, becomes longer by the first time ΔT, so that it is possible to suppress deterioration of the video quality with respect to the original video.

[0099] Note that, in the example shown in FIG. 10, even if it is not determined to delay the transfer timing of the fifth frame data by the first time ΔT when the capture of the fourth frame data ends at time t4, when it is determined that the difference value D(3) is smaller than the difference value D(4) when the capture of the fifth frame data ends at time t5, the fifth frame data is transferred to the first display panel 11L at time t5', which is delayed by the first time ΔT from time t5.

[0100] (Effect of the present embodiment) As described above, the display device 10 of the present embodiment includes a first display panel 11L, a second display panel 11R, and a control device 12 that transfers the image data of the first frame to the first display panel 11L, transfers the image data of the second frame following the first frame to the second display panel 11R, transfers the image data of the third frame following the second frame to the first display panel 11L, and transfers the image data of the fourth frame following the third frame to the second display panel 11R. The control device 12 calculates a first difference value between the image data of the first frame and the image data of the second frame. The control device 12 calculates a second difference value between the image data of the second frame and the image data of the third frame. When the first difference value is smaller than the second difference value, the control device 12 delays the transfer timing of the image data of the third frame by a first time ΔT. When the first difference value is larger than the second difference value, the control device 12 delays the transfer timing of the image data of the fourth frame by a first time ΔT.

[0101] For example, the control device 12 calculates a difference value D(m) between the nth frame data and the (n + 1)th frame data, and calculates a difference value D(m + 1) between the (n + 1)th frame data and the (n + 2)th frame data. When the difference value D(m) is smaller than the difference value D(m + 1), the control device 12 delays the transfer timing of the (n + 2)th frame data by a first time ΔT. On the other hand, when the difference value D(m) is larger than the difference value D(m + 1), the control device 12 delays the transfer timing of the (n + 3)th frame data by a first time ΔT.

[0102] According to the present embodiment as described above, the time during which the first video P1 and the second video P2 with low similarity are simultaneously displayed, that is, the time during which two videos with low similarity are simultaneously projected onto the left and right eyes of the user M is shortened by the first time ΔT, so the discomfort given to the user can be reduced. Further, according to the present embodiment, the time during which the first video P1 and the second video P2 with high similarity are simultaneously displayed, that is, the time during which two videos with high similarity are simultaneously projected onto the left and right eyes of the user M is lengthened by the first time ΔT, so it is possible to suppress the deterioration of the video quality with respect to the original video.

[0103] In this embodiment, the first time ΔT is half the time of one frame. In this way, by making the first time ΔT half the time of one frame, it is possible to balance and achieve the effect of reducing the discomfort given to the user and the effect of suppressing the deterioration of the video quality with respect to the original video.

[0104] An example of the electronic device of this embodiment, the HMD100, includes a display device 10. As described above, according to the HMD100 including the display device 10, since the time during which two videos with low similarity are simultaneously projected onto the left and right eyes of the user M is shortened by the first time ΔT, the discomfort given to the user can be reduced. Also, since the time during which two videos with high similarity are simultaneously projected onto the left and right eyes of the user M is lengthened by the first time ΔT, it is possible to suppress the deterioration of the video quality with respect to the original video.

[0105] As described above, the embodiments of the present disclosure have been described. However, the technical scope of the present disclosure is not limited to the above embodiments, and various modifications can be made without departing from the spirit of the present disclosure. For example, the following modification examples can be considered.

[0106] (1) In the above embodiment, the form in which the first time ΔT is fixed at half the time of one frame is exemplified. However, the present disclosure is not limited to this. The first time ΔT may be changed according to the similarity of the image data between two consecutive frames.

[0107] For example, when the ratio of the pixel values satisfying the first condition to all the pixel values included in the image data of the first frame is equal to or greater than the first threshold, the control device 12 may set the first time ΔT to half the time of one frame. When the ratio is less than the first threshold, the control device 12 may set the first time ΔT to less than half the time of one frame. The first condition is that for the pixel value at any coordinate included in the image data of the first frame, the amount of change in the pixel value at the same coordinate as the above-mentioned arbitrary coordinate among the pixel values included in the image data of the second frame is equal to or less than the second threshold.

[0108] Specifically, when the ratio of the pixel values that satisfy the first condition among all the pixel values included in the n-th frame data is 50% or more, the control device 12 sets the first time ΔT to half of the time of one frame. When the ratio is less than 50%, the control device 12 sets the first time ΔT to 1 / 4 of the time of one frame. The first condition is that for the pixel value at any coordinate included in the n-th frame data, the amount of change in the pixel value at the same coordinate as the above-mentioned arbitrary coordinate among the pixel values included in the (n + 1)-th frame data is 70% or less.

[0109] According to the above-described modification, the higher the similarity of the image data between two consecutive frames, the longer the first time ΔT becomes. That is, the higher the similarity of the image data between two consecutive frames, the longer the time during which the highly similar first video P1 and second video P2 are simultaneously displayed, that is, the time during which two highly similar videos are simultaneously projected onto the left and right eyes of the user M becomes the first time ΔT. Therefore, the deterioration of the video quality with respect to the original video can be more strongly suppressed.

[0110] (2) FIG. 11 is a block diagram showing a modification of the display device 10. As shown in FIG. 11, the display device 10 may include a control device 12A instead of the control device 12. The control device 12A includes a first video receiving unit 310, a second video receiving unit 320, a first frame buffer 330, a second frame buffer 340, a frame comparison unit 350, a timing generation unit 360, a first image transmission unit 370, and a second image transmission unit 380. The control device 12A transfers the image data of odd frames to the first display panel 11L and transfers the image data of even frames to the second display panel 11R.

[0111] The first video receiving unit 310 receives a video signal supplied from a video supply device and acquires the image data of odd frames from the video signal. The first video receiving unit 310 outputs the image data of odd frames acquired from the video signal to the first frame buffer 330.

[0112] The second video receiving unit 320 receives a video signal supplied from a video supply device, and acquires image data of even frames from the video signal. The second video receiving unit 320 outputs the image data of the even frames acquired from the video signal to a second frame buffer 340.

[0113] The first frame buffer 330 holds the image data of odd frames input from the first video receiving unit 310 in units of one frame. The second frame buffer 340 holds the image data of even frames input from the second video receiving unit 320 in units of one frame.

[0114] The frame comparison unit 350 calculates a difference value of image data between two consecutive frames based on the image data of odd frames held in the first frame buffer 330 and the image data of even frames held in the second frame buffer 340. The frame comparison unit 350 outputs the calculation result of the difference value to a timing generation unit 360.

[0115] Based on the calculation result of the difference value obtained from the frame comparison unit 350, the timing generation unit 360 generates the transfer timing of the image data of odd frames held in the first frame buffer 330 and the transfer timing of the image data of even frames held in the second frame buffer 340. Similar to the timing generation unit 240, the timing generation unit 360 executes the timing generation process shown in the flowchart of FIG. 7.

[0116] The first image transmission unit 370 transfers the image data of odd frames held in the first frame buffer 330 to the first display panel 11L based on the transfer timing generated by the timing generation unit 360. The second image transmission unit 380 transfers the image data of even frames held in the second frame buffer 340 to the second display panel 11R based on the transfer timing generated by the timing generation unit 360.

[0117] (3) In the above embodiment, the HMD 100 was exemplified as the electronic device including the display device 10. The present disclosure is not limited thereto, and examples of the electronic device including the display device of the present disclosure include a display device for a personal computer, a projector, a smartphone, and a tablet terminal.

[0118] [Summary of the Present Disclosure] Hereinafter, a summary of the present disclosure is appended.

[0119] (Appended Note 1) A display device comprising: a first display panel; a second display panel; and a control device that transfers the image data of a first frame to the first display panel, transfers the image data of a second frame, which is the next frame of the first frame, to the second display panel, transfers the image data of a third frame, which is the next frame of the second frame, to the first display panel, and transfers the image data of a fourth frame, which is the next frame of the third frame, to the second display panel, wherein the control device calculates a first difference value between the image data of the first frame and the image data of the second frame, calculates a second difference value between the image data of the second frame and the image data of the third frame, and when the first difference value is smaller than the second difference value, delays the transfer timing of the image data of the third frame by a first time, and when the first difference value is larger than the second difference value, delays the transfer timing of the image data of the fourth frame by the first time.

[0120] In the display device described in Supplementary Note 1, when the first difference value between the image data of the first frame and the image data of the second frame is smaller than the second difference value between the image data of the second frame and the image data of the third frame, the transfer timing of the image data of the third frame is delayed by the first time. In this case, the time during which the video based on the image data of the first frame and the video based on the image data of the second frame are simultaneously displayed becomes longer by the first time. That is, the time during which two videos with high similarity are simultaneously displayed on the first display panel and the second display panel becomes longer by the first time. On the other hand, the time during which the video based on the image data of the second frame and the video based on the image data of the third frame are simultaneously displayed becomes shorter by the first time. That is, the time during which two videos with low similarity are simultaneously displayed on the first display panel and the second display panel becomes shorter by the first time.

[0121] Also, in the display device described in Supplementary Note 1, when the first difference value is larger than the second difference value, the transfer timing of the image data of the fourth frame is delayed by the first time. In this case, the time during which the video based on the image data of the second frame and the video based on the image data of the third frame are simultaneously displayed becomes longer by the first time. That is, the time during which two videos with high similarity are simultaneously displayed on the first display panel and the second display panel becomes longer by the first time. On the other hand, the time during which the video based on the image data of the third frame and the video based on the image data of the fourth frame are simultaneously displayed becomes shorter by the first time. That is, the time during which two videos with low similarity are simultaneously displayed on the first display panel and the second display panel becomes shorter by the first time.

[0122] Therefore, according to the display device described in Supplementary Note 1, since the time during which two videos with low similarity are simultaneously displayed, that is, the time during which videos with low similarity are simultaneously projected onto the user's left and right eyes, becomes shorter by the first time, the discomfort given to the user can be reduced. Also, according to the display device described in Supplementary Note 1, since the time during which two videos with high similarity are simultaneously displayed, that is, the time during which videos with high similarity are simultaneously projected onto the user's left and right eyes, becomes longer by the first time, it is possible to suppress deterioration of the video quality with respect to the original video.

[0123] (Supplementary Note 2) The display device according to Supplementary Note 1, wherein the first time is half the time of one frame.

[0124] According to the display device described in Supplementary Note 2, since the first time is half the time of one frame, it is possible to balance the effect of reducing the sense of discomfort given to the user and the effect of suppressing the deterioration of the video quality with respect to the original video.

[0125] (Supplementary Note 3) When the ratio of the pixel values satisfying the first condition among all the pixel values included in the image data of the first frame is equal to or greater than the first threshold value, the control device sets the first time to half the time of one frame. When the ratio is less than the first threshold value, the control device sets the first time to less than half the time of one frame. The first condition is that, for the pixel value at any coordinate included in the image data of the first frame, the amount of change in the pixel value at the same coordinate as the arbitrary coordinate among the pixel values included in the image data of the second frame is equal to or less than the second threshold value. The display device according to Supplementary Note 1.

[0126] According to the display device described in Supplementary Note 3, the higher the similarity of the image data between two consecutive frames, the longer the first time. That is, the higher the similarity of the image data between two consecutive frames, the longer the first time, which is the time during which two videos with high similarity are displayed simultaneously, that is, the time during which two videos with high similarity are projected onto the left and right eyes of the user simultaneously. Therefore, the deterioration of the video quality with respect to the original video can be more strongly suppressed.

[0127] (Supplementary Note 4) An electronic device including the display device according to any one of Supplementary Notes 1 to 3.

[0128] According to the electronic device described in Supplementary Note 4, since the time during which two videos with low similarity are simultaneously projected onto the user's left and right eyes is shortened only by the first time, the sense of discomfort given to the user can be reduced. Also, since the time during which two videos with high similarity are simultaneously projected onto the user's left and right eyes is lengthened only by the first time, it is possible to suppress deterioration of the video quality with respect to the original video.

Explanation of Signs

[0129] 100… Head-mounted display (electronic device), 111… Optical module, 111A… First optical module, 111B… Second optical module, 120… Frame, 10… Display device, 11… Display panel, 11L… First display panel, 11R… Second display panel, 12, 12A… Control device, 210… Video reception unit, 220… Frame buffer, 230… Frame comparison unit, 240… Timing generation unit, 250… Image distribution unit, M… User

Claims

1. A first display panel, a second display panel, a control device that transfers the image data of the first frame to the first display panel, transfers the image data of the second frame following the first frame to the second display panel, transfers the image data of the third frame following the second frame to the first display panel, and transfers the image data of the fourth frame following the third frame to the second display panel, and comprising, wherein the control device calculates a first difference value between the image data of the first frame and the image data of the second frame, calculates a second difference value between the image data of the second frame and the image data of the third frame, when the first difference value is smaller than the second difference value, delays the transfer timing of the image data of the third frame by a first time, when the first difference value is larger than the second difference value, delays the transfer timing of the image data of the fourth frame by the first time, a display device.

2. The display device according to claim 1, wherein the first time is half the time of one frame.

3. The control device sets the first time to half the time of one frame when the ratio of the pixel values satisfying the first condition among all the pixel values included in the image data of the first frame is equal to or greater than a first threshold value, sets the first time to less than half the time of one frame when the ratio is less than the first threshold value, wherein the first condition is that, for the pixel value at any coordinate included in the image data of the first frame, the amount of change in the pixel value at the same coordinate as the arbitrary coordinate among the pixel values included in the image data of the second frame is equal to or less than a second threshold value, the display device according to claim 1.

4. An electronic device comprising the display device according to any one of claims 1 to 3.

Images