Display device and method

Abstract

A display device according to an embodiment includes: a display panel having a display area for displaying an image; a plurality of light sources for irradiating light in order to display the image in the display area; and a control unit for causing the light sources corresponding to the plurality of areas obtained by dividing the display area to emit light in sequence for each of the areas. The control unit causes the light source corresponding to the area determined according to the image in the plurality of areas to repeatedly emit light during one frame period in which the image is displayed in the display area.

Description

Technical Field

[0001] Embodiments of the present invention relate to a display device and a method. Background Art

[0002] In a display device such as a liquid crystal display device, a backlight is disposed on the back side of a display panel having a display area, and an image can be displayed in the display area by irradiating the display panel with light from the backlight.

[0003] Here, a technique is known in which a display area is divided into a plurality of areas and a backlight is locally and sequentially caused to emit light corresponding to each of the areas (hereinafter referred to as backlight scanning).

[0004] However, in the case of a display device using the above-mentioned backlight scanning, it is difficult to increase the brightness (value) of an image displayed in the display area.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Publication No. 2010-060817 Summary of the invention

[0008] Problems to be solved by the invention

[0009] Therefore, an object of the present invention is to provide a display device and method capable of improving the brightness of an image.

[0010] Means used to solve problems

[0011] A display device according to an embodiment includes: a display panel having a display area for displaying an image; a plurality of light sources for irradiating light in order to display the image in the display area; and a control unit for causing the light sources corresponding to the plurality of areas obtained by dividing the display area to emit light in sequence for each of the areas. The control unit causes the light sources corresponding to the areas determined based on the image in the plurality of areas to repeatedly emit light during one frame period in which the image is displayed in the display area. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a diagram showing an example of the configuration of an image display system according to an embodiment.

[0013] Figure 2 This is a diagram showing an example of the structure of a display device.

[0014] Figure 3 This is a diagram for explaining the outline of a head-up display.

[0015] Figure 4 This is a diagram for explaining the outline of backlight scanning.

[0016] Figure 5 This is a diagram showing an example of a circuit configuration of a backlight.

[0017] Figure 6 A diagram showing an example of an image displayed on a display device.

[0018] Figure 7 It means when display Figure 6 The image shown is a diagram showing an example of the timing when the switches provided for the respective areas are turned on.

[0019] Figure 8 This is a diagram showing another example of an image displayed on the display device.

[0020] Fig. 9 It means when display Figure 8 The image shown is a diagram showing an example of the timing when the switches provided for the respective areas are turned on.

[0021] Fig.10 This is a diagram showing another example of an image displayed on the display device.

[0022] Fig.11 It means when display Fig.10 The image shown is a diagram showing an example of the timing when the switches provided for the respective areas are turned on.

[0023] Fig.12 This is a diagram for explaining a case where backlight scanning is repeatedly performed on two areas among a plurality of areas.

[0024] Fig.13 This is a diagram showing a circuit configuration of a backlight in which the order of turning on switches is changed.

[0025] Fig.14 This is a diagram for explaining a situation where images are displayed alternately and flicker.

[0026] Fig.15 This is a block diagram showing an example of the structure of a display device according to a modification of the present embodiment.

[0027] Fig.16 This is a diagram showing an example of a circuit configuration of a backlight.

[0028] Fig.17 It is a diagram for explaining the operation of the display device.

[0029] Fig.18 It is a diagram for explaining the operation of the display device. DETAILED DESCRIPTION

[0030] Hereinafter, embodiments will be described with reference to the drawings.

[0031] In addition, the disclosed content is only an example, and any suitable changes that can be easily thought of by a person skilled in the art while maintaining the main idea of ​​the invention are of course included in the scope of the present invention. In addition, in order to make the description clearer, the drawings schematically show the width, thickness, shape, etc. of each part compared with the actual situation, but this is only an example and does not limit the interpretation of the present invention. In addition, in this specification and each figure, the same reference numeral is given to the constituent elements that perform the same or similar functions as the constituent elements described in the previous figures, and repeated detailed descriptions are appropriately omitted.

[0032] Figure 1 An example of the structure of the image display system of this embodiment is shown. Figure 1 As shown, the image display system 10 includes a control device 11 and a display device 12 .

[0033] The control device 11 corresponds to a host CPU or the like for controlling the operation of the image display system 10 , and supplies an image or the like to be displayed on the display device 12 as described later to the display device 12 .

[0034] The display device 12 is, for example, a liquid crystal display device (LCD: Liquid Crystal Display) including a display panel including a liquid crystal layer, and displays an image supplied from the control device 11 on a display area of ​​the display panel.

[0035] In addition, Figure 1 Although omitted in the figure, the image display system 10 further includes, for example, a storage device that stores programs or other data required for executing various processes in the image display system 10 .

[0036] In addition, in the present embodiment, the control device 11 and the display device 12 are described as independent devices, but the control device 11 and the display device 12 may be configured as an integral unit.

[0037] Figure 2 express Figure 1 An example of the structure of the display device 12 is shown. Figure 2 As shown, the display device 12 includes a signal processing unit 121 , a display panel 122 , a panel driving unit (panel driver) 123 , a backlight (light source device) 124 , a backlight control unit (light source driving unit) 125 , and the like.

[0038] The signal processing unit 121 is a calculation processing unit that controls the operation of the display panel 122 and the backlight 124. The signal processing unit 121 is connected to a panel driving unit 123 for driving the display panel 122 and a backlight control unit 125 for driving the backlight 124.

[0039] Here, the image supplied from the control device 11 to the display device 12 includes, for example, a matrix of pixel data called a Bayer arrangement. Such an image is converted into an image signal including RGB components by performing image processing (Bayer conversion). In addition, the image processing is performed in the control device 11, for example.

[0040] The signal processing unit 121 receives an image signal on which the image processing has been performed as described above from the control device 11. The signal processing unit 121 performs necessary processing on the input image signal and outputs the signal to the panel driving unit 123 (display panel 122).

[0041] Furthermore, the signal processing unit 121 generates a backlight control signal based on the input image signal, and outputs the backlight control signal to the backlight control unit 125 .

[0042] The display panel 122 has a display area DA. In the display area DA, a plurality of pixels PX are arranged in a two-dimensional matrix (matrix shape).

[0043] The panel driving unit 123 includes a signal output circuit 123a and a scanning circuit 123b. The signal output circuit 123a is electrically connected to the display panel 122 via a signal line DTL. The signal output circuit 123a holds the image signal output from the signal processing unit 121 and sequentially outputs the image signal to the display panel 122.

[0044] The scanning circuit 123b is electrically connected to the display panel 122 through the scanning line SCL. The scanning circuit 123b controls the on and off of a switching element for selecting a pixel in the display panel 122.

[0045] The backlight 124 is disposed, for example, on the back side of the display panel 122, and irradiates light to the display panel 122. A plurality of light sources are provided in the backlight 124. As the light source provided in the backlight, for example, a light emitting diode element (hereinafter simply referred to as LED) is used.

[0046] The backlight control unit 125 adjusts the current or duty ratio supplied to the backlight 124 based on the backlight control signal output from the signal processing unit 121 , for example, to control the amount (intensity) of light irradiated from the backlight 124 to the display panel 122 .

[0047] In such a display device 12, corresponding to the actions of the panel driving unit 123 (signal output circuit 123a and scanning circuit 123b) and the backlight control unit 125, the image signal (pixel signal) output from the signal processing unit 121 is written in sequence for each of the multiple pixels PX (display rows) arranged in a matrix in the display panel 122 illuminated by the light from the backlight 124, thereby enabling an image to be displayed on the display area DA of the display panel 122.

[0048] In addition, the display device 12 (image display system 10) of the present embodiment can be used for a head-up display (HUD) that displays an image in the driver's field of vision by reflecting the image on a projection surface such as a windshield of a car. According to the head-up display, a virtual image can be reproduced at a location about 4 meters in front of the windshield, and the driver can confirm the image without moving his or her sight significantly.

[0049] Here, refer to Figure 3 , the overview of the head-up display is explained. Figure 3 As shown, the head-up display includes a display device 12 for projecting an image and, for example, two concave mirrors M1 and M2. According to such a structure, the image output from the display device 12 (i.e., the image displayed on the display device 12) is reflected and focused by the concave mirrors M1 and M2, and is projected, for example, onto the inner surface (projection surface) of the windshield FG of the car.

[0050] The image projected in this way is reflected toward the driver's side by the windshield FG, and forms a virtual image V several meters in front of the windshield FG.

[0051] Here, the mirrors M1 and M2 constituting a part of the head-up display are assumed to be concave mirrors for the purpose of explanation, but the mirrors M1 and M2 may not be concave mirrors, and may be other optical components such as half mirrors, Fresnel mirrors, etc. In addition, the image may be projected not onto the windshield FG but onto a transparent reflective plate or the like provided in front of the driver.

[0052] In addition, as described above, the image displayed on the display device 12 is supplied from the control device 11, but the control device 11 Figure 3 omitted.

[0053] Here, as described above, the display device 12 of this embodiment adopts backlight scanning. The so-called backlight scanning refers to a method of dividing the display area DA (the light-emitting surface of the backlight 124) into a plurality of areas and controlling the light emission of the backlight 124 to sequentially scan the plurality of areas. In other words, in the backlight scanning, the backlight 124 is locally emitted sequentially in a manner corresponding to each area obtained by dividing the display area DA. Such backlight scanning is useful for improving image quality.

[0054] Below is an overview of backlight scanning, using Figure 4 Here, Figure 4 As shown, the display area DA is divided into a plurality of areas DA1 to DA8. Figure 4In the example shown, the display area DA is divided so that a plurality of areas DA1 to DA8 extend in the Y direction (first direction) and are arranged side by side in the X direction (second direction).

[0055] Here, if Figure 4 As shown in FIG. 1 , the backlight 124 is provided with a plurality of LEDs 124a arranged in a matrix. In the backlight scanning, first, the LEDs 124a corresponding to the area DA1 (here, four LEDs 124a) are made to emit light (light up). The LEDs 124a corresponding to the area DA1 are LEDs arranged directly below the area DA1 and illuminate the area DA1 in order to display an image in the area DA1. The same is true for the LEDs 124a corresponding to the other areas DA2 to DA8.

[0056] Next, the light emission of the LED 124a corresponding to the area DA1 is stopped (the LED 124a is turned off), and the LED 124a corresponding to the area DA2 is made to emit light. The backlight scanning is performed by repeating the same control for the areas DA3 and thereafter.

[0057] in addition, Figure 5 FIG. 1 shows an example of a circuit structure of the backlight 124. As described above, in the backlight 124, a plurality of LEDs 124a are arranged in a matrix. Figure 4 For example, the anodes of the four LEDs 124a corresponding to the area DA1 described in the figure are electrically connected to one end (anode common) of a common switch (anode switch) 124b. On the other hand, the cathodes of the four LEDs 124a corresponding to the area DA1 and the other end of the switch 124b are electrically connected to the backlight control unit 125. By turning on such a switch 124b and supplying an anode power supply from the other end of the switch 124b, the LEDs 124a corresponding to the area DA1 can be made to emit light.

[0058] Here, the area DA1 (corresponding to the plurality of LEDs 124a) is described, but the other areas DA2 to DA8 are the same. That is, in this embodiment, switches 124b are provided for the respective areas DA1 to DA8 obtained by dividing the display area, and the switches 124b are controlled so as to be turned on in sequence, thereby realizing the above-mentioned backlight scanning.

[0059] In addition, in this embodiment, the two switches 124b are not turned on at the same time, but the switches 124b are turned on one by one.

[0060] In addition, Figure 5In FIG. 1 , the numbers marked near each switch 124 b indicate the order in which the switch 124 b is turned on. Figure 5 In the backlight 124 shown, it is shown that the switches 124b are turned on in sequence from the left side when the backlight is scanned.

[0061] In addition, typically, the maximum brightness of the backlight 124 is limited by the instantaneous current that can flow through the LED 124a provided in the backlight 124, and the instantaneous current is determined according to the rated value (specification or performance) of the LED 124a, the current supply capacity of the backlight control unit 125 (LED driver) or the power supply design, etc.

[0062] Therefore, when it is desired to temporarily increase the brightness of an image displayed on the display device 12 using the backlight scanning described above, the rated value of the LED 124a and the backlight control unit 125 must be designed according to the increased brightness, which increases the manufacturing cost of the display device 12.

[0063] Therefore, the display device 12 of this embodiment has a structure capable of improving image brightness without increasing manufacturing costs.

[0064] Below, refer to Figure 6 to Figure 9 The operation of the display device 12 according to this embodiment will be described.

[0065] first, Figure 6 An example of an image displayed on the display device 12 is shown. Figure 7 Indicates when display Figure 6 The image 200 shown is a timing at which the switches 124b provided for the areas DA1 to DA8 are turned on.

[0066] In addition, when the display device 12 of this embodiment is applied to Figure 3 In the case of the head-up display described in Figure 6 The image 200 shown corresponds to an image that is usually presented to the driver, and the image 200 includes information such as the speed of the car driven by the driver and the legal speed of the road on which the car is traveling.

[0067] In the case of a structure in which LED 124a is lit in each area unit of areas DA1 to DA8 as described above, in order to display Figure 6 In the illustrated image 200 , it is necessary to cause the LED 124 a to emit light in all of the areas DA1 to DA8 .

[0068] In this case, the backlight control unit 125 performs the following steps: Figure 7 As shown, the switches 124b provided for the areas DA1 to DA8 are sequentially turned on, so that the LEDs 124a corresponding to the areas DA1 to DA8 are sequentially lit.

[0069] In addition, the period from when the LED 124a corresponding to the area DA1 starts to emit light to when the plurality of LEDs 124a corresponding to the area DA8 stop emitting light corresponds to the period (1 frame period) during which the image 200 (1 frame) is displayed. That is, when the image 200 is displayed, in 1 frame period, each of the eight switches 124b provided for the areas DA1 to DA8 is turned on once (that is, the backlight scan is performed once). In addition, in the present embodiment, "the backlight scan is performed once" means that each of the switches 124b provided for the areas (here, DA1 to DA8) that are the objects of the backlight scan is turned on once.

[0070] then, Figure 8 Another example of an image displayed on the display device 12 is shown. Fig. 9 Indicates when display Figure 8 The image 300 shown is the timing at which the switches 124b provided for the areas DA1 to DA8 described above are turned on.

[0071] In addition, when the display device 12 of this embodiment is applied to Figure 3 In the case of the head-up display described in Figure 8 The image 300 shown corresponds to an image provided to the driver in an emergency, and the image 300 includes information notifying the driver that the road on which the car is being driven is in a slippery state, for example.

[0072] In the case of a structure in which LED 124a is lit in each area unit of areas DA1 to DA8 as described above, in order to display Figure 8 In the image 300 shown, LED 124a can be made to emit light in areas DA3 to DA6 of areas DA1 to DA8. In other words, the left and right areas with a certain width in image 300 (specifically, areas DA1, DA2, DA7 and DA8) are black areas, which are areas that do not need to be illuminated by backlight 124.

[0073] In this case, the backlight control unit 125 performs the following steps: Fig. 9 As shown, the switches 124b provided for the areas DA3 to DA6 are sequentially turned on, so that the LEDs 124a corresponding to the areas DA3 to DA6 are sequentially illuminated.

[0074] Here, when the above-mentioned image 200 is displayed, the eight switches 124b provided for the areas DA1 to DA8 are each turned on once in one frame period, and when the image 300 is displayed, the eight switches 124b can be turned on once in one frame period. Fig. 9As shown, the four switches 124b provided for the areas DA3 to DA6 (areas to be the target of backlight scanning) are each turned on twice (that is, the backlight scanning is performed twice).

[0075] That is, in the present embodiment, when an image that requires the LEDs 124a corresponding to the entire display area DA (areas DA1 to DA8) to emit light (light up) is not displayed (the entire screen is lit image) as in Image 200, but an image that can be displayed by only causing the LEDs 124a corresponding to a portion of the display area DA (areas DA1 to DA8) to emit light (light up) is displayed (the partially lit image) as in Image 300, only the corresponding LED 124a is repeatedly illuminated during one frame.

[0076] In addition, in the present embodiment, the image displayed by the display device 12 is supplied from the control device 11 to the display device 12, but the image (e.g., image 200 or 300) can be determined by the control device 11 based on, for example, information maintained within the image display system 10, information obtained from outside the image display system 10 (e.g., a server device or various sensors, etc.), and the like.

[0077] Furthermore, as described above, the area where the LED 124a needs to emit light in order to display the image supplied from the control device 11 can be determined on the control device 11 side based on the image and indicated (notified) to the display device 12, or it can be determined on the display device 12 side (for example, the signal processing unit 121, etc.) based on the image.

[0078] In addition, in this embodiment, the case where the LED 124a corresponding to the areas DA3 to DA6 is repeatedly emitted during one frame period (i.e., the backlight scanning is repeatedly performed on the areas DA3 to DA6), but the areas corresponding to the repeatedly emitted LED 124a may not be continuous.

[0079] Specifically, in the case where the partially lit image is displayed, for example Fig.10 In the case of the image 400 shown, the LEDs 124 a corresponding to the areas DA1 , DA2 , DA7 , and DA8 among the areas DA1 to DA8 may be sequentially lit.

[0080] In this case, the backlight control unit 125 performs the following steps: Fig.11 As shown, the switches 124b provided for the areas DA1, DA2, DA7 and DA8 are turned on in sequence, so that the LEDs 124a corresponding to the areas DA1, DA2, DA7 and DA8 respectively emit light repeatedly during one frame period.

[0081] In addition, the areas DA1 to DA8 described in the present embodiment are examples, and the number of areas where the display area DA is divided may be a number other than 8, and the shapes of the areas may be different from those described in the present embodiment. Furthermore, in the present embodiment, the number of LEDs 124a corresponding to the areas DA1 to DA8 is described as 4, but the number of LEDs 124a corresponding to the areas DA1 to DA8 may be a number other than 4, and the configuration of the plurality of LEDs 124a may be different from that described in the present embodiment. In addition, for example, Fig. 9 , etc., shows an example in which the backlight scanning is repeated twice and one frame period ends at the timing when the switch 124b set for area DA6 switches from the on state to the off state, but it is also possible to control the light emission of the backlight 124 (a plurality of LEDs 124a) in such a manner that one frame period ends at the timing when, for example, the switch 124b set for an area other than area DA6 (areas DA3 to DA5) switches from the on state to the off state, according to the period of maintaining the on state of each switch 124b. That is, in this embodiment, the LED 124a corresponding to at least one area of ​​the areas (e.g., DA3 to DA6) determined according to the image is made to emit light multiple times during one frame period.

[0082] As described above, in this embodiment, when backlight scanning is adopted in which the LEDs (light sources) 124a corresponding to the multiple areas (for example, areas DA1 to DA8) obtained by dividing the display area DA are illuminated in sequence in each of the areas, during one frame of an image displayed on the display area DA, the LEDs 124a corresponding to the areas determined according to the image among the multiple areas (that is, the LEDs 124a that need to emit light when the image is displayed) are repeatedly illuminated.

[0083] That is, in this embodiment, when the area where the LED 124a emits light according to the displayed image can be reduced (that is, a partially lit image is displayed), by increasing the number of backlight scans per unit time (one frame period), the light emission time of the LED 124a corresponding to the area to be scanned by the backlight increases. Therefore, in this embodiment, the brightness of the image displayed on the display device 12 can be increased.

[0084] Specifically, in the case of a configuration in which backlight scanning is repeatedly performed on four areas (areas DA3 to DA6, etc.) among the plurality of areas DA1 to DA8 obtained by dividing the display area DA as described above, the same configuration as in Figure 7 Compared with the configuration in which backlight scanning is performed on all of the areas DA1 to DA8 as the object as described in , LED 124a is illuminated twice as many times (ie, twice as long) for one area, so the brightness of the image is also doubled.

[0085] Although specific examples of images are omitted, for example, Fig.12 In the case of a structure in which backlight scanning is repeatedly performed on two areas DA4 and DA5 among areas DA1 to DA8 as objects as shown, LED 124a is illuminated four times (i.e., for four times the period) for one area, compared to a structure in which backlight scanning is repeatedly performed on all of the areas DA1 to DA8, so the brightness of the image is also quadrupled.

[0086] That is, in this embodiment, when displaying an image (partially lit image) in which the area where LED 124a emits light (lit area) becomes 1 / 2 or 1 / 4 of the display area DA, the maximum brightness of the image can be made twice or four times that of the normal image (the entire screen is lit image).

[0087] Furthermore, according to the above configuration, the brightness of an image can be improved without changing, for example, the rated value of the LED 124 a , the backlight control unit 125 (LED driver), and the power supply design, so that an increase in manufacturing cost can be suppressed.

[0088] Furthermore, in the present embodiment, for example, an image 200 (first image) displayed in normal times and an image 300 (second image) displayed in an emergency can be displayed, and the area determined based on the image 200 is different from the area determined based on the image 300. That is, in the present embodiment, when switching between a full-screen lit image such as the image 200 and a partially lit image such as the image 300 for display, the brightness of the partially lit image can be increased when the partially lit image is displayed.

[0089] In addition, in the present embodiment, the plurality of LEDs 124a are arranged in a matrix, and the plurality of regions DA1 to DA8 obtained by dividing the display region DA extend in the Y direction (first direction) and are arranged in the X direction (second direction). In addition, the LEDs 124a corresponding to the plurality of regions DA1 to DA8 are electrically connected to the switches 124b provided for the regions. In the present embodiment, by turning on the switches 124b in sequence, backlight scanning can be performed.

[0090] In addition, in this embodiment, if Figure 5 As described in the description, the corresponding LED 124a is illuminated in the order of the areas DA1 to DA8, but for example, depending on the specifications or performance of the backlight control unit 125, there may be a case where the switch 124b (LED 124a) for starting the backlight scan must be fixed. In this case, for example, Figure 5When the switch 124b is turned on in the order described in , the switch 124b provided for the area DA1 must be turned on first, and the image 200 and the like cannot be displayed as described in the present embodiment.

[0091] In contrast, for example, Fig.13 As shown in the change Figure 5 In the case where the switches 124b described in the above are turned on, the image 200 can be displayed with high brightness even if the switch 124b for starting backlight scanning needs to be fixed as described above. That is, in this embodiment, the plurality of switches 124b can be turned on in a predetermined order according to the images displayed on the display device 12.

[0092] In addition, in the present embodiment, by increasing the brightness of the image displayed by the display device 12 as described above, the visual recognition of an image displayed in an emergency such as the image 300 can be improved, and attention can be urged based on the information notified in the emergency. However, from the perspective of urging the attention, Fig.14 As shown, display control may be performed such that the images 300 and 400 that can be displayed with high brightness are periodically switched (that is, alternately displayed so as to flash).

[0093] Furthermore, when the display device 12 is used as a head-up display, the brightness of the backlight 124 (a plurality of LEDs 124a) when displaying the normal image 200 may be adjusted based on the illuminance (brightness) of the external light measured by the illuminance sensor, for example. Even in such a configuration, when displaying the emergency image 300, the backlight 124 is automatically illuminated at the maximum brightness (i.e., the current of the backlight control unit 125 is automatically set to the maximum) as described above, thereby further improving the visual recognition.

[0094] In addition, although it is described here that the backlight 124 is illuminated at maximum brightness, the backlight 124 (LED 124a) does not necessarily have to be illuminated at maximum brightness, and the brightness of the backlight 124 may be changed according to the timing of repeatedly performing backlight scanning in one frame period. With such a structure, it is possible to improve the brightness of the image and achieve power saving.

[0095] In addition, in the present embodiment, the plurality of LEDs 124a provided in the backlight 124 are driven in a passive matrix manner, but for example, as long as the light emitting (lighting) time of the plurality of LEDs 124a is limited to a part of a frame period, the present embodiment can also be applied to a display device 12 in which the plurality of LEDs 124a are driven in an active matrix manner.

[0096] In addition, in the present embodiment, the display device 12 is described as including one backlight control unit 125, but the display device 12 may also be Fig.15 As shown in the figure, two backlight control units (a first backlight control unit 125a and a second backlight control unit 125b) are provided (hereinafter referred to as a modified example).

[0097] Fig.16 An example of a circuit configuration of the backlight 124 included in the display device 12 according to the present modification is shown.

[0098] In this modified example, a portion of the LEDs 124a (first light source) among the plurality of LEDs 124a arranged in a matrix in the backlight 124 is connected to the first backlight control unit 125a, and the remaining LEDs 124a (second light source) among the plurality of LEDs 124a are connected to the second backlight control unit 125b. This is similar to the above-mentioned Figure 5 different.

[0099] exist Fig.16 In the illustrated example, the first backlight control unit 125 a is electrically connected to the LEDs 124 a corresponding to the areas DA1 to DA4 among the plurality of areas DA1 to DA8 obtained by dividing the display area DA.

[0100] On the other hand, the second backlight control unit 125 b is electrically connected to the LEDs 124 a corresponding to the areas DA5 to DA8 among the plurality of areas DA1 to DA8 obtained by dividing the display area DA.

[0101] In addition, the switch 124b is provided for each of the plurality of areas DA1 to DA8 as described above. Figure 5 As explained in , detailed description is omitted here.

[0102] Thus, the first backlight control unit 125a can sequentially turn on the switches 124b provided for the areas DA1 to DA4, thereby enabling the LEDs 124a corresponding to the areas DA1 to DA4 to emit light in sequence. Similarly, the second backlight control unit 125b can sequentially turn on the switches 124b provided for the areas DA5 to DA8, thereby enabling the LEDs 124a corresponding to the areas DA5 to DA8 to emit light in sequence.

[0103] When the configuration including the first backlight control unit 125 a and the second backlight control unit 125 b is provided as in the present modification, the two switches 124 b can be turned on at the same time.

[0104] Below, refer to Fig.17 and Fig.18 , describing the operation of the display device 12 of this variation.

[0105] first, Fig.17 Indicates that when the above Figure 6 The image 200 shown is the timing at which the switches 124b provided for the areas DA1 to DA8 are turned on.

[0106] To show Figure 6 In the illustrated image 200 , it is necessary to cause the LED 124 a to emit light in all of the areas DA1 to DA8 .

[0107] In this case, the first backlight control unit 125a performs the following steps: Fig.17 As shown, the switches 124b provided for the areas DA1 to DA4 are sequentially turned on, so that the plurality of LEDs 124a corresponding to the areas DA1 to DA4 are sequentially lit.

[0108] The period from when the LED 124a corresponding to the area DA1 starts to emit light to when the LED 124a corresponding to the area DA4 stops emitting light corresponds to the period (one frame period) during which the image 200 is displayed. That is, in this modification, when the image 200 is displayed, each of the plurality of switches 124b provided for the areas DA1 to DA4 is turned on once during one frame period (that is, backlight scanning is performed once).

[0109] Similarly, the second backlight control unit 125 b turns on the switches 124 b provided for the areas DA5 to DA8 in sequence, thereby causing the LEDs 124 a corresponding to the areas DA5 to DA8 to emit light in sequence.

[0110] The period from when the LED 124a corresponding to the area DA5 starts to emit light to when the LED 124a corresponding to the area DA8 stops to emit light corresponds to the period (one frame period) during which the image 200 is displayed. That is, in this modification, when the image 200 is displayed, each of the plurality of switches 124b provided for the areas DA5 to DA8 is turned on once during one frame period (that is, backlight scanning is performed once).

[0111] Thus, in this modification, by making the LEDs 124a corresponding to two of the plurality of areas DA1 to DA8 emit light simultaneously, the light emission time of each of the LEDs 124a can be made longer, so that the LEDs 124a can emit light for a longer time. Figure 7 The brightness can be improved compared to the situation described in .

[0112] then, Fig.18 Indicates that when the above Figure 8 The image 300 shown is the timing at which the switches 124b provided for the areas DA1 to DA8 are turned on.

[0113] To show Figure 8In the image 300 shown, the LED 124 a may be caused to emit light in the areas DA3 to DA6 among the areas DA1 to DA8 as described above.

[0114] In this case, the first backlight control unit 125a performs the following steps: Fig.18 As shown, the switches 124b provided for the areas DA3 and DA4 are turned on in sequence, so that the LEDs 124a corresponding to the areas DA3 and DA4 are illuminated in sequence.

[0115] Similarly, the second backlight control unit 125b sequentially turns on the LEDs 124b provided for the areas DA5 and DA6, thereby sequentially causing the LEDs 124a corresponding to the areas DA5 and DA6 to emit light.

[0116] Here, when the above-mentioned image 200 is displayed, the four switches 124b provided for the areas DA1 to DA4 are each turned on once in one frame period, and when the image 300 is displayed, it is possible to Fig.18 As shown, the two switches 124b set for areas DA3 and DA4 are each turned on twice (i.e., backlight scanning is performed twice), and the two switches 124b set for areas DA5 and DA6 are each turned on twice (i.e., backlight scanning is performed twice).

[0117] That is, in this variant example, there are a first backlight control unit 125a and a second backlight control unit 125b, the first backlight control unit 125a causes the LEDs 124a corresponding to areas DA3 and DA4 among the LEDs 124a corresponding to areas determined by an image (for example, areas DA3 to DA6) to repeatedly emit light, and the second backlight control unit 125b causes the LEDs 124a corresponding to areas DA5 and DA6 among the LEDs 124a corresponding to areas determined by an image (for example, areas DA3 to DA6) to repeatedly emit light.

[0118] In the present modification, such a configuration can increase the number of backlight scans per unit time (one frame period), so the brightness of an image displayed on the display device 12 can be improved.

[0119] Specifically, in the case of a configuration in which backlight scanning is repeatedly performed on four areas (areas DA3 to DA6) among the plurality of areas DA1 to DA8 obtained by dividing the display area DA as described above, the backlight scanning is repeated as described above. Fig.17 Compared with the configuration in which backlight scanning is performed on all of the areas DA1 to DA8 as described in , LED 124a is made to emit light twice as many times (that is, twice as long) for one area, so the brightness of the image is also doubled.

[0120] That is, even in the case of a structure with two backlight control units as in this modification, when an image (partially lit image) is displayed in which the area where LED 124a emits light (lit area) becomes 1 / 2 of the display area DA, the maximum brightness of the image can be made twice that of the normal image (the entire screen is lit image). In addition, although the details are omitted, when an image is displayed in which the area where LED 124a emits light becomes 1 / 4 of the display area DA, the maximum brightness of the image can be made four times that of the normal image.

[0121] In addition, in the above-mentioned present embodiment (and variations of the present embodiment), it is described that the LED backlight 124 (direct-down type LED backlight) is arranged at a position corresponding to the entire surface of the display panel 122 (i.e., directly below the display panel 122), but the backlight 124 may also be an edge-type LED backlight in which the LED is arranged at a position corresponding to the left, right, top, or bottom ends of the display panel 122.

[0122] Furthermore, when the display device 12 of this embodiment is a liquid crystal display device as described above, the display device 12 may be configured to perform local dimming for controlling the brightness distribution of the backlight 124 according to the image. That is, this embodiment can be used together with local dimming.

[0123] Furthermore, the display device 12 of this embodiment may be, for example, an LED display having a plurality of light-emitting diode elements (light sources) arranged corresponding to a plurality of pixels, or an organic EL display having a plurality of organic electroluminescent elements (light sources) arranged corresponding to a plurality of pixels.

[0124] Hereinafter, the invention of this embodiment will be supplemented.

[0125] [C1]

[0126] A display device comprising:

[0127] A display panel having a display area for displaying images;

[0128] a plurality of light sources for irradiating light in order to display an image in the display area; and

[0129] A control unit, which makes the light sources corresponding to the plurality of regions obtained by dividing the display region emit light in sequence for each of the regions;

[0130] The control section repeatedly causes a light source corresponding to a region among the plurality of regions specified based on the image to emit light during one frame period in which the image is displayed in the display region.

[0131] [C2]

[0132] The display device as described in [C1],

[0133] The images displayed in the display area include a first image and a second image;

[0134] The area specified based on the first image is different from the area specified based on the second image.

[0135] [C3]

[0136] The display device as described in [C1] or [C2],

[0137] The plurality of light sources are arranged in a matrix in the first direction and the second direction;

[0138] The plurality of regions extend in the first direction and are arranged in the second direction.

[0139] [C4]

[0140] The display device as described in [C3],

[0141] It also includes a plurality of switches respectively provided for the plurality of areas;

[0142] The light sources corresponding to the plurality of regions are electrically connected to switches provided for the regions.

[0143] [C5]

[0144] The display device as described in [C4],

[0145] The plurality of switches are configured to be turned on in a sequence predetermined based on the image.

[0146] [C6]

[0147] The display device as described in any one of [C1] to [C5],

[0148] The control unit includes a first control unit that causes a first light source among the plurality of light sources to emit light, and a second control unit that causes a second light source among the plurality of light sources that is different from the first light source to emit light;

[0149] The first control unit repeatedly emits light from a first light source among light sources corresponding to an area determined based on the image during one frame period in which the image is displayed in the display area;

[0150] The second control unit repeatedly controls the second light source among the light sources corresponding to the area specified based on the image to emit light during one frame period in which the image is displayed in the display area.

[0151] [C7]

[0152] The display device as described in any one of [C1] to [C6],

[0153] The display panel comprises a liquid crystal layer;

[0154] The plurality of light sources are provided in a backlight disposed on the rear surface of the display panel.

[0155] [C8]

[0156] The display device as described in any one of [C1] to [C6],

[0157] The display panel includes a plurality of pixels arranged in a matrix in the display area;

[0158] The plurality of light sources include a plurality of light emitting diode elements arranged corresponding to the plurality of pixels.

[0159] [C9]

[0160] The display device as described in any one of [C1] to [C6],

[0161] The display panel includes a plurality of pixels arranged in a matrix in the display area;

[0162] The plurality of light sources include a plurality of organic electroluminescent elements arranged corresponding to the plurality of pixels.

[0163] [C10]

[0164] A method is performed by a display device including a display panel having a display area for displaying an image and a plurality of light sources for irradiating light to display the image in the display area, comprising the following steps:

[0165] When the light sources corresponding to the multiple areas obtained by dividing the above-mentioned display area are made to emit light in sequence for each of the areas, during one frame period of displaying an image in the above-mentioned display area, the light source corresponding to the area determined according to the image among the above-mentioned multiple areas is repeatedly emitted light.

[0166] [C11]

[0167] As described in [C10],

[0168] The images displayed in the display area include a first image and a second image;

[0169] The area specified based on the first image is different from the area specified based on the second image.

[0170] [C12]

[0171] The method as described in [C10] or [C11],

[0172] The plurality of light sources are arranged in a matrix in the first direction and the second direction;

[0173] The plurality of regions extend in the first direction and are arranged in the second direction.

[0174] [C13]

[0175] As described in [C12],

[0176] The display device further comprises a plurality of switches respectively provided for the plurality of areas;

[0177] The light sources corresponding to the plurality of regions are electrically connected to switches provided for the regions.

[0178] [C14]

[0179] As described in [C13],

[0180] The plurality of switches are configured to be turned on in a sequence predetermined based on the image.

[0181] [C15]

[0182] The method according to any one of [C10] to [C14],

[0183] The step of emitting light includes the step of causing a first light source among the plurality of light sources to emit light and the step of causing a second light source among the plurality of light sources that is different from the first light source to emit light;

[0184] The step of causing the first light source to emit light includes the step of causing the first light source among the light sources corresponding to the area determined based on the image to repeatedly emit light during one frame period in which the image is displayed in the display area;

[0185] The step of causing the second light source to emit light includes the step of causing the second light source among the light sources corresponding to the area specified based on the image to repeatedly emit light during one frame period in which the image is displayed in the display area.

[0186] [C16]

[0187] As described in [C10] to [C15],

[0188] The display panel comprises a liquid crystal layer;

[0189] The plurality of light sources are provided in a backlight disposed on the rear surface of the display panel.

[0190] [C17]

[0191] As described in [C10] to [C15],

[0192] The display panel includes a plurality of pixels arranged in a matrix in the display area;

[0193] The plurality of light sources include a plurality of light emitting diode elements arranged corresponding to the plurality of pixels.

[0194] [C18]

[0195] As described in [C10] to [C15],

[0196] The display panel includes a plurality of pixels arranged in a matrix in the display area;

[0197] The plurality of light sources include a plurality of organic electroluminescent elements arranged corresponding to the plurality of pixels.

[0198] Based on the display devices described above as the embodiments of the present invention, all display devices designed and implemented as appropriate by a person skilled in the art also belong to the scope of the present invention as long as they include the gist of the present invention.

[0199] In the scope of the concept of the present invention, those skilled in the art can think of various variations, and these variations should also be understood to belong to the scope of the present invention. For example, for the above-mentioned embodiment, the form obtained by the addition, deletion or design change of the constituent elements appropriately performed by those skilled in the art, or the form obtained by the addition, omission or condition change of the process is also included in the scope of the present invention as long as it has the gist of the present invention.

[0200] Furthermore, other effects and functions brought about by the forms described in the above embodiments, which are clearly obtained from the description of this specification or which are appropriately conceived by those skilled in the art, should of course be understood to be brought about by the present invention.

[0201] Description of symbols

[0202] 10…image display system, 11…control device, 12…display device, 121…signal processing unit, 122…display panel, 123…panel driving unit, 123a…signal output circuit, 123b…scanning circuit, 124…backlight, 124a…LED (light source), 124b…switch, 125…backlight control unit, 125a…first backlight control unit, 125b…second backlight control unit, DTL…signal line, SCL…scanning line.

Claims

1. A display device, characterized in that: have: A display panel having a display area for displaying images; a plurality of light sources for irradiating light in order to display an image in the display area; A control unit, causing the light sources corresponding to the plurality of regions obtained by dividing the display region to emit light in sequence in each region; as well as A plurality of switches are respectively set for the plurality of areas; The control unit repeatedly emits light corresponding to a region among the plurality of regions determined based on the image during one frame period in which the image is displayed in the display region; The plurality of light sources are arranged in a matrix in the first direction and the second direction; The plurality of regions extend in the first direction and are arranged in the second direction; The anodes of the light sources corresponding to the plurality of regions are electrically connected to switches provided for the regions.

2. The display device according to claim 1, wherein: The images displayed in the display area include a first image and a second image; The area specified based on the first image is different from the area specified based on the second image.

3. The display device according to claim 1, wherein: The plurality of switches are configured to be turned on in a sequence predetermined based on the image.

4. The display device according to any one of claims 1 to 3, characterized in that The control unit includes a first control unit that causes a first light source among the plurality of light sources to emit light, and a second control unit that causes a second light source among the plurality of light sources that is different from the first light source to emit light; The first control unit repeatedly emits light from a first light source among light sources corresponding to an area determined based on the image during one frame period in which the image is displayed in the display area; The second control unit repeatedly controls the second light source among the light sources corresponding to the area specified based on the image to emit light during one frame period in which the image is displayed in the display area.

5. The display device according to any one of claims 1 to 3, characterized in that The display panel comprises a liquid crystal layer; The plurality of light sources are provided in a backlight disposed on the back side of the display panel.

6. The display device according to any one of claims 1 to 3, characterized in that The display panel includes a plurality of pixels arranged in a matrix in the display area; The plurality of light sources include a plurality of light emitting diode elements arranged corresponding to the plurality of pixels.

7. The display device according to any one of claims 1 to 3, characterized in that The display panel includes a plurality of pixels arranged in a matrix in the display area; The plurality of light sources include a plurality of organic electroluminescent elements arranged corresponding to the plurality of pixels.

8. A display method, which is a method performed by a display device, the display device comprising a display panel having a display area for displaying an image, and a plurality of light sources for irradiating light in order to display the image in the display area, the display method being characterized in that: The following steps are required: When light sources corresponding to the plurality of regions obtained by dividing the display region are caused to emit light in sequence in each region, during one frame period in which an image is displayed in the display region, a light source corresponding to a region determined according to the image among the plurality of regions is caused to emit light repeatedly; The display device comprises a plurality of switches respectively provided for the plurality of areas; The plurality of light sources are arranged in a matrix in the first direction and the second direction; The plurality of regions extend in the first direction and are arranged in the second direction; The anodes of the light sources corresponding to the plurality of regions are electrically connected to switches provided for the regions.

9. The display method according to claim 8, characterized in that: The images displayed in the display area include a first image and a second image; The area specified based on the first image is different from the area specified based on the second image.

10. The display method according to claim 8, characterized in that: The plurality of switches are configured to be turned on in a sequence predetermined based on the image.

11. The display method according to any one of claims 8 to 10, characterized in that: The step of emitting light includes the step of causing a first light source among the plurality of light sources to emit light and the step of causing a second light source among the plurality of light sources that is different from the first light source to emit light; The step of causing the first light source to emit light includes the step of causing the first light source among the light sources corresponding to the area determined based on the image to repeatedly emit light during one frame period in which the image is displayed in the display area; The step of causing the second light source to emit light includes the step of causing the second light source among the light sources corresponding to the area specified based on the image to repeatedly emit light during one frame period in which the image is displayed in the display area.

12. The display method according to any one of claims 8 to 10, characterized in that: The display panel comprises a liquid crystal layer; The plurality of light sources are provided in a backlight disposed on the back side of the display panel.

13. The display method according to any one of claims 8 to 10, characterized in that: The display panel includes a plurality of pixels arranged in a matrix in the display area; The plurality of light sources include a plurality of light emitting diode elements arranged corresponding to the plurality of pixels.

14. The display method according to any one of claims 8 to 10, characterized in that: The display panel includes a plurality of pixels arranged in a matrix in the display area; The plurality of light sources include a plurality of organic electroluminescent elements arranged corresponding to the plurality of pixels.

Images