JP2012053367A - Image display device and image display method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve a problem of deterioration in the display quality of a moving image resulting from a blurred moving image due to crosstalk by illumination from multiple light sources in a moving image area in an image display device including the multiple light sources.SOLUTION: An image display device in the invention includes: a display unit for displaying a video; light sources A and B for illuminating the display unit; a PMW control unit for controlling switch-on and switch-off of the light sources A and B; and a moving image detection unit for detecting a moving image area. The display unit comprises an area SA illuminated only by the light source A, an area SB illuminated only by the light source B, and an overlapped area SD illuminated by both of the light sources A and B. When the moving image area falls under the overlapped area SD, the PMW control unit switches off the light sources A and B simultaneously during a period of scanning the moving image area, and thereby deterioration in the image quality due to crosstalk is reduced.

Description

  The present invention relates to an image display device including a light source for backlighting an image display unit. In particular, the present invention relates to a light source control technique related to moving image display.

  As an image display device such as a liquid crystal display device, in order to realize a good image quality, a backlight type that irradiates the image display unit with a light source such as a cold cathode tube lamp (CCFL) or a light emitting diode (LED) is known. It has been. As a method of arranging the light source, there are a direct type arranged behind the image display unit, an edge type arranged with a light source substantially on the same plane as the light guide plate provided behind the image display unit, and the like.

  The backlight method can increase the brightness of the display screen, but it has a problem that brightness unevenness and image quality deterioration (moving image blur, etc.) when displaying moving images are conspicuous.

  On the other hand, a method for suppressing a deterioration in image quality when displaying a moving image by driving control of the light source has been considered. For example, dividing the display area into a plurality of blocks, arranging a plurality of light sources corresponding to each divided block, turning off the light sources corresponding to the blocks in the display area where the moving image is displayed, etc. The display apparatus which suppresses is proposed (for example, refer patent documents 1-3).

JP 2008-83427 A JP 2005-99367 A JP 2004-309592 A

  However, the above-described conventionally proposed image display device has the following problems.

  As shown in FIG. 13a, the first conventional image display device 500 has a scanning period of the moving image region 102 when there is one region in which the object 101 moves in the display screen (hereinafter, abbreviated as “moving image region”). In the middle, the black and white were inserted by turning off the light sources A and B, thereby improving the moving image blur peculiar to liquid crystal televisions and the like. However, as shown in FIG. 13b, when two moving image areas 102 and 104 exist in the display screen, black is inserted by turning off the light sources A and B during the scanning period of the moving image area 102 to suppress moving image blur. However, black insertion is not performed on the moving image area 104, and moving image blur cannot be suppressed.

  On the other hand, FIG. 14A shows a second conventional image display device that can suppress moving image blur even when there are a plurality of moving image areas in the display screen.

  In FIG. 14a, the display screen of the image display device 600 is divided into two upper and lower display areas, and the light sources A and B corresponding to the display areas are individually driven and controlled to perform black insertion for the moving image areas 102 and 104. (This is referred to as “double blinking”). Specifically, by setting the black insertion period TB1 of the light source A and the black insertion period TB2 of the light source B for each of the moving image areas 102 and 104, moving image blur can be suppressed even when there are a plurality of moving image areas. .

  However, as shown in FIG. 14b, the luminance on the display screen due to the lighting of the light sources A and B gradually decreases from the upper and lower end portions toward the center within the irradiation range. Therefore, in the CR region where the irradiation light from the light sources A and B overlaps, even if one of the light sources A and B is turned off, it is affected by the other light source, so that complete black insertion is not achieved. That is, when the drive control is individually performed on the light sources A and B, crosstalk occurs due to mutual influence. For example, when the moving image area 104 is in the CR area and a part of the moving image area 102 is included in the CR area, the effect of black insertion in the black insertion periods TB3 and TB4 is reduced. In particular, the moving image area 104 is greatly affected by the light source B even if the light source A is turned off, and the effect of black insertion is reduced.

  The occurrence of crosstalk is irrelevant to the timing of turning on (H) / turning off (L) of the light sources A and B.

  An object of the present invention is to provide an image display device and an image display method for suppressing deterioration in image quality when a moving image area is present in a display screen in a backlight type image display device irradiated with a plurality of light sources. .

  In order to solve the above problems, an image display apparatus according to the present invention includes a display unit that displays an image, a first light source and a second light source that irradiate the display unit, and turning on and off the first light source and the second light source. A light source control means for controlling, and a moving picture area extracting means for extracting a moving picture area including a moving picture in the display area of the display means, wherein the display areas are only the first display area and the second light source irradiated only by the first light source. When the moving image area is included in the third display area, the light source control is performed during the scanning period of the moving image area. Means turns off the first light source and the second light source.

  With such a configuration, when an area including a moving image (hereinafter abbreviated as a moving image area) is extracted and the moving image area is included in the third display area irradiated with the first light source and the second light source, the moving image area During the scanning period, the first light source and the second light source can be turned off. Therefore, it is possible to reduce the occurrence of crosstalk due to the irradiation of the first light source and the second light source and to realize high-quality image display with reduced moving image blur for the moving image region included in the third display region.

  Furthermore, in the image display device of the present invention, a region where the moving image in the moving image region and the first display region overlap is defined as a first overlapping region, and a region where the moving image in the moving image region overlaps the third display region is defined as a third overlapping region. When the size of the third overlapping area is greater than or equal to the size of the first overlapping area, the light source control means turns off the first light source and the second light source during the moving image scanning period in the moving image area. When the size of the overlapping region is smaller than the size of the first overlapping region, the light source control unit turns off the first light source during the scanning period of the first overlapping region.

  With such a configuration, when the size of the third overlapping region is greater than or equal to the size of the first overlapping region, the first light source and the second light source are turned off during the moving image scanning period in the moving image region, and the third When the size of the overlapping region is smaller than the size of the first overlapping region, the first light source can be turned off during the scanning period of the first overlapping region. Therefore, even when the moving image in the moving image region overlaps the first display region and the third display region, occurrence of crosstalk due to irradiation of the first light source and the second light source is appropriately reduced, and moving image blur is suppressed. High quality image display can be realized.

  Further, in the image display device of the present invention, when the moving period of the moving image area exceeds the extinguishing period set in advance for the first light source and the second light source, the light source control means is outside the moving period of the moving image area. The intensity of the first light source and the second light source is set higher than a predetermined intensity.

  With such a configuration, when the turn-off period of the first light source and the second light source with respect to the scanning period of the moving image area exceeds a predetermined value, the lighting intensity outside the moving period of the moving image area can be made higher than the predetermined value. Therefore, a reduction in the brightness of the display image due to an increase in the turn-off period of the first light source and the second light source is suppressed, and crosstalk occurs due to irradiation of the first light source and the second light source even when the size of the moving object changes. Can be appropriately reduced, and high-quality image display with reduced moving image blur can be realized.

  The image display device of the present invention further includes a moving image region characteristic detecting unit that detects a moving image characteristic in the moving image region extracted by the moving image region extracting unit, and the first moving image region extracted by the moving image region extracting unit is the first moving image region. The second moving image area included in the three display areas and extracted by the moving image area extracting unit is included in the first display area, and the first based on the characteristics of the moving image in the first moving image area detected by the moving image area characteristic detecting unit. The priority is compared with the second priority based on the characteristics of the moving image in the second moving image area detected by the moving image area characteristic detecting means, and if the first priority is equal to or higher than the second priority, the first moving image area During the scanning period, the light source control means turns off the first light source and the second light source. On the other hand, when the first priority is lower than the second priority, the light source control means performs the first light source control means during the scanning period of the first moving image area. Turn off the two light sources and scan the second moving image area Light source control means in turns off the first light source.

  With such a configuration, when the first priority is equal to or higher than the second priority, the first light source and the second light source are turned off during the scanning period of the first moving image area, and the first priority is the second priority. If smaller, the second light source can be turned off during the scanning period of the first moving image area, and the first light source can be turned off during the scanning period of the second moving image area. Therefore, even when the priority of the two moving images based on the characteristics of the moving images is different, the occurrence of crosstalk due to the irradiation of the first light source and the second light source is appropriately reduced, and high-quality image display that suppresses moving image blur is realized. can do.

  In the image display device of the present invention, when the moving image characteristic is luminance, the priority based on the luminance increases as the luminance increases, and when the moving image characteristic is movement, the priority based on the movement varies. The higher the speed, the larger the moving image characteristic, and the higher the high frequency component amount, the higher the priority based on the high frequency component amount.

  With such a configuration, it is possible to compare priorities based on the luminance, movement, and high-frequency component amount of the first moving image region and the second moving image region. Therefore, by detecting the luminance, movement, and high frequency component amount of the first moving image area and the second moving image area, occurrence of crosstalk due to irradiation of the first light source and the second light source is appropriately reduced, and moving image blur is suppressed. High quality image display can be realized.

  The image display apparatus according to the present invention includes display means for displaying an image, N (N is an integer of 2 or more) first light source to N light source, and N first light sources to Nth light that irradiate the display means. Light source control means for controlling turning on / off of the light source, and moving picture area extracting means for extracting a moving picture area including a moving picture in the display area of the display means, wherein the display area is the mth light source (m is an integer from 1 to N) ) Only, and the kth light source (k is an integer from 1 to (N-1)) and the (k, k + 1) th display region irradiated with the (k + 1) light source. Is included in the (k, k + 1) th display area, the light source control means turns off the kth light source and the (k + 1) th light source during the scanning period of the moving image area.

  With this configuration, when a moving image area including a moving image in the display area of the display unit is extracted and the moving image area is included in the (k, k + 1) th display area, the kth light source is used during the scanning period of the moving image area. The (k + 1) th light source can be turned off. Therefore, the occurrence of crosstalk due to irradiation from two adjacent light sources is reduced with respect to the moving image area included in the (k, k + 1) display area irradiated by the kth light source and the (k + 1) light source, and the moving image High-quality image display with reduced blur can be realized.

  The image display method of the present invention controls a display step of displaying an image on the display means, and lighting / extinguishing of N (N is an integer of 2 or more) first light source to N light source that irradiates the display means. And a moving image region extracting step for extracting a moving image region including a moving image in the display region of the display means, where the moving image region is the k-th light source (k is an integer from 1 to (N−1)) and When included in the display area irradiated with the (k + 1) light source, the kth light source and the (k + 1) light source are turned off in the light source control step during the scanning period of the moving image area.

  By such a method, a moving image area including a moving image in the display area of the display unit is extracted, and when the moving image area is included in the display areas irradiated by the kth light source and the (k + 1) light source, During the scanning period, the kth light source and the (k + 1) th light source can be turned off. Therefore, the occurrence of crosstalk due to irradiation from a plurality of light sources can be reduced, and high-quality image display with reduced moving image blur can be realized.

  According to the image display device and the image display method of the present invention, when a moving image area is included in a display area irradiated by two adjacent light sources, the two adjacent light sources are turned off during the scanning period of the moving image area. Can do. Therefore, the occurrence of crosstalk due to irradiation from a plurality of light sources can be reduced, and high-quality image display with reduced moving image blur can be realized.

It is a rear view of the image display apparatus in Embodiment 1 of this invention. It is a side view of the image display apparatus in Embodiment 1 of this invention. It is a lighting characteristic figure of the light source of the image display apparatus in Embodiment 1 of this invention. It is a drive waveform figure of the light source of the image display apparatus in Embodiment 1 of this invention. It is a figure which shows an example of the display state of the moving image in Embodiment 1 of this invention. It is a figure which shows an example of the display state of the moving image in Embodiment 1 of this invention. It is a figure which shows an example of the display state of the moving image in Embodiment 1 of this invention. It is a figure which shows an example of the display state of the moving image in Embodiment 1 of this invention. It is a figure which shows an example of the display state of the moving image in Embodiment 1 of this invention. It is a figure which shows an example of the display state of two moving images in Embodiment 1 of this invention. It is a figure which shows an example of the display state of two moving images in Embodiment 1 of this invention. It is a figure which shows an example of the display state of two moving images in Embodiment 1 of this invention. It is a drive waveform figure of the light source of the image display apparatus in Embodiment 1 of this invention. It is a block diagram of the image display apparatus in Embodiment 1 of this invention. It is a figure which shows the other structural example of the light source using LED of the image display apparatus in Embodiment 1 of this invention. It is a figure which shows the other structural example of the light source using the lamp | ramp of the image display apparatus in Embodiment 1 of this invention. It is a flowchart of the light source control in case the one moving image area | region exists in Embodiment 1 of this invention. It is a drive waveform figure of the light source of the image display apparatus in Embodiment 2 of this invention. It is a block diagram of the image display apparatus in Embodiment 2 of this invention. It is a drive waveform diagram of a backlight light source when there is one moving image area in the first conventional image display device. It is a drive waveform diagram of a backlight light source when there are two moving image areas in the first conventional image display device. It is a drive waveform figure of the backlight light source in the 2nd conventional image display device. It is another drive waveform diagram of the backlight light source in the second conventional image display device.

  In the following, an embodiment of an image display device of the present invention (hereinafter abbreviated as “this device”) is described taking a liquid crystal display device as an example. The image display device has a light source that illuminates a display screen. If it is, it is not limited to a liquid crystal display device.

(Embodiment 1)
FIG. 1 a is a rear view of the apparatus 1, FIG. 1 b is a side view of the apparatus 1, and FIG. 1 c is a lighting characteristic diagram of a light source of the apparatus 1.

  As shown in FIGS. 1a and 1b, the apparatus 1 includes a display unit 2 and a holding base 3 using a liquid crystal display panel or the like. In addition, a light source A as an assembly of a plurality of light sources a1, a2,..., An for backlight is disposed at the upper end portion of the display surface S on the back surface of the display unit 2. Similarly, a light source B as an aggregate of a plurality of light sources b1, b2,..., Bn for backlight is arranged at the lower end of the display surface S. As the light source, a semiconductor light emitting material such as an LED can be used.

  A light guide plate 4 is disposed on the back surface of the display unit 2 at a position connecting the light source A and the light source B, and output light from the light sources A and B is converted into surface light emission by the light guide plate 4 and displayed on the display surface S. Irradiate. The light source A irradiates a substantially upper part of the display surface S, and the light source B irradiates a substantially lower part of the display surface S, so that the entire area of the display surface S is irradiated with a predetermined brightness.

  FIG. 1 c is a lighting characteristic diagram showing the luminance distribution of the light guide plate 4 based on the light sources A and B.

  The luminance of the light source A gradually decreases in accordance with the distance from the light source (distance from the upper end of the display unit 2) in the irradiation range CA. Further, the luminance of the light source B gradually decreases in accordance with the distance from the light source (distance from the lower end of the display unit 2) in the irradiation range CB. On the display surface S of the apparatus 1, the region from the upper end of the display unit 2 to the threshold A is irradiated only by the light source A, and the region from the lower end of the display unit 2 to the threshold B is irradiated only by the light source B. In addition, the range of the display surface S irradiated from the light sources A and B is defined as an overlapping irradiation range D.

  As shown in FIG. 1a, the display surface S of the present apparatus 1 has a region SA irradiated from only the light source A, a region SB irradiated only from the light source B, and a region irradiated from the light sources A and B (hereinafter referred to as the overlapping regions). , Which is abbreviated as “overlapping area”).

  Note that image writing to the display unit 2 is performed from the upper end to the lower end of the display surface S.

  FIG. 2 is a drive waveform diagram of the light source of the apparatus 1 and shows the relationship between the video display synchronization signal for the display surface S and the drive waveforms of the backlight light sources A and B.

  As shown in FIG. 2, when the object M1 is moving in the direction of the arrow in the overlapping area SD, the apparatus 1 extracts a moving image area G1 including the object M1. Since the extracted moving image area G1 is included in the overlapping area SD, the light sources A and B are turned off during the scanning period of the moving image area G1, and the black insertion period T is provided. Thereby, with respect to the moving image region G1 included in the overlapping region SD, occurrence of crosstalk due to overlapping irradiation of the light sources A and B can be suppressed, and good display quality without moving image blur can be realized.

  Below, the drive control of the light sources A and B corresponding to the various display states of a moving image is demonstrated.

  First, the case where one moving image area is included in any one of the area SA, the area SB, and the overlapping area SD will be described with reference to FIGS. 3A to 3C.

  FIG. 3a shows a case where one moving image area including the object M1 moving on the display surface S in the direction of the arrow (rightward) is included in the overlapping area SD. In this case, the drive control of the light sources A and B is performed. Is as already described in FIG.

FIG. 3b shows a case where one moving image area including the object M1 is included in the area SA irradiated from only the light source A. In this case, the light source A is turned off during the scanning period of the object M1 to perform black insertion. ,
The light source B is turned off at a predetermined timing regardless of the scanning period of the object M1.

FIG. 3c shows a case where one moving image area including the object M1 is included in the area SB irradiated from only the light source B. In this case, the light source B is turned off during the scanning period of the object M1, and black insertion is performed. ,
The light source A is turned off at a predetermined timing regardless of the scanning period of the object M1.

  Next, a case where a part of one moving image area overlaps the overlapping area SD will be described with reference to FIGS. 4 and 5.

  FIG. 4 shows a case where one moving image area G2 including the object M2 moving on the display surface S in the direction of the arrow (rightward) straddles the area SA and the overlapping area SD.

  In this case, a region where the moving image region G2 overlaps the overlapping region SD is a region L1, a region where the moving image region G2 overlaps the region SA is a region L2, and the sizes of the region L1 and the region L2 are compared. As shown in FIG. 4, when the region L1 is larger than the region L2, the light sources A and B are simultaneously turned off during the scanning period of the region L1 to perform black insertion. Note that the drive control of the light sources A and B is similar when the moving image area G2 extends over the area B and the overlapping area SD.

  FIG. 5 shows a case where one moving image region G3 including the object M2 moving on the display surface S in the direction of the arrow (rightward) straddles the region SA and the overlapping region SD.

  In this case, a region where the moving image region G3 and the overlapping region SD overlap is a region L1, a region where the moving image region G3 and the region SA overlap is a region L2, and the sizes of the region L1 and the region L2 are compared. As shown in FIG. 5, when the region L1 is smaller than the region L2, the light source A is turned off during the scanning period of the region L2 to perform black insertion, and the light source B is not related to the scanning period of the object M2. Turns off at a predetermined timing. The drive control of the light sources A and B is the same when the moving image area G3 extends over the overlapping area SD with the area B.

  4 and 5, for example, in FIG. 4, the sizes of the region L <b> 1 and the region L <b> 2 are compared. When the region L <b> 1 is larger than the region L <b> 2, the light source A, Although an example in which B is turned off at the same time and black is inserted has been described, depending on the set brightness from the light source brightness setting unit 121, the light source brightness A and B can be turned off simultaneously during the period of the region L2. . In this case, the width of the black insertion period corresponding to the set brightness from the light source brightness setting unit 121 is compared with the height in the vertical direction of the moving image area G2, and the black insertion period corresponding to the set brightness from the light source brightness setting unit 121 is compared. When the width is larger than the vertical height of the moving image area G2, the light source luminances A and B may be turned off simultaneously during the period of the area L2 in addition to the area L1. The same applies to FIG.

  Next, a case where each of the two moving image areas is included in any one of the area SA, the area SB, and the overlapping area SD will be described with reference to FIGS. 6a to 6c.

  As shown in FIGS. 6a to 6c, when there is a moving image area including the object M1 moving in the right direction and a moving image area including the object M3 moving in the left direction, the characteristics of the moving image area including the object M1 The characteristics of the moving image area including the object M3 are detected, and the priorities of the objects M1 and M3 are determined based on the detected characteristics.

  Here, as the characteristics of the moving image area that determines the priority, there are those that are greatly involved in moving image blur such as the brightness of the object, the moving speed of the object, the amount of high-frequency components in the moving image area, and the presence of telop and character scroll. . The priority level based on the characteristics of these moving image areas increases as the brightness increases in the case of luminance, increases as the speed increases in the case of moving speed, and in the case of high-frequency component amounts, the amount of high-frequency components As the number increases, the telop or character scroll becomes higher than the moving image area where the telop or character scroll exists.

  As shown in FIG. 6a, when the priority of the object M3 in the area SA is higher than or equal to the priority of the object M1 in the overlap area SD, the light source A is turned off during the scanning period of the moving image area of the object M3. The light source B is turned off during the scanning period of the moving image area of the object M1.

  As shown in FIG. 6b, when the priority of the object M1 in the overlap area SD is higher than or equal to the priority of the object M3 in the area SB, the light sources A and B during the scanning period of the moving image area of the object M1. At the same time.

  As shown in FIG. 6c, when the priority of the object M1 in the overlapping area SD is higher than or equal to that of the object M3, the light sources A and B are simultaneously turned off during the scanning period of the object M1 moving image area. Similarly, when the priority of the object M3 is higher than or equal to that of the object M1, the light sources A and B are turned off simultaneously during the scanning period of the object M3 moving image area. However, depending on the set brightness from the light source brightness setting unit 121, the light sources A and B can be turned off at the same time during the scanning period including both the object M1 and the object M3, and moving image blur of both objects can be reduced.

  In FIGS. 6a to 6c, even when the moving image area including the low priority object extends over the area SA (or area SB) and the overlapping area SD, the drive control (lights on / off) for the light sources A and B is performed. ) Is performed based on which of the area SA, the area SB, and the overlapping area SD a moving image area including an object with a high priority. Therefore, the drive control for the light sources A and B is the same as that described with reference to FIGS.

  FIG. 7 shows a case where the moving image area including the object M6 moving in the right direction is included in the overlapping area SD and the moving image area including the object M7 (telop) moving in the right direction is included in the area SB. ing. In this case, as in FIG. 6a, since the priority of the object M7 (telop) is higher than the priority of the object M6, the light source A is turned off during the scanning period of the object M6 included in the overlapping area SD, and the area SB The light source B is turned off during the scanning period of the object M7 (telop) included therein. Even if the moving image area including the object M7 (telop) extends over the area SB and the multi-area SD, the drive control for the light sources A and B does not change.

  In this way, even when two moving image areas exist, a high-quality image that effectively reduces the occurrence of crosstalk and suppresses moving image blur by providing a priority based on the characteristics of the moving image area. Display can be realized.

  FIG. 8 is a configuration diagram of the apparatus 1.

  As shown in FIG. 8, the display unit 110 of the present apparatus 1 includes a video display panel 111 that displays video, a light source A 112 that irradiates the video display panel 111, and a light source B 113, and controls the light source A 112 and the light source B 113. The light source control unit 120 is connected. The light source control unit 120 includes a light source luminance setting unit 121, a moving image detection unit 122, an existing area determination unit 123, a moving image priority determination unit 124, a PWM control unit 125, and a PWM pulse generation unit 126.

  The light source luminance setting unit 121 sets the luminance of the light source A 112 and the light source B 113 for the PWM control unit 125. Note that the luminance setting value is determined based on the feature amount of the video, the external light intensity, the setting value by the user, and the like.

  The moving image detection unit 122 detects the moving image area of the current frame. For example, the moving image detection unit 122 compares the image signal of the current frame with the image signal of the previous frame in units of pixels, and cumulatively adds the difference for one horizontal scanning period. The presence or absence of a moving image on the horizontal scanning line may be detected based on whether or not the obtained value exceeds a predetermined value.

  The existence area determination unit 123 is a relationship between the moving image area detected by the moving image detection unit 122 and the above-described area SA, area SB, and overlapping area SD (the moving image area exists in the overlapping area SD, or the moving image area is the area SA. A relationship such as existing across the overlapping area SD) is determined. Then, the determination result is output to the moving picture priority determination unit 124 as an existing area determination signal.

  Based on the presence area determination signal, the video priority determination unit 124 obtains the priority of each video area when there are a plurality of video areas, and determines the highest priority video area. The moving image area is determined as a black insertion target, and information on the black insertion target moving image area is output to the PWM control unit 125.

  When the black insertion target moving image area is included in the overlapping area SD, the PWM control unit 125 sets the black insertion phase signals A and B for designating the period during which black insertion is performed for the light source A 112 and the light source B 113 to the same value. Output to the PWM pulse generator 126. Note that the length of the period during which black is inserted is determined based on the luminance setting value from the light source luminance setting unit 121.

  The PWM pulse generator 126 outputs the PWM pulse A and the PWM pulse B based on the black insertion phase signals A and B, and turns on and off the light source A112 and the light source B113.

  In the first embodiment of the present invention, the LED edge type backlight system in which the LED light sources are arranged at both the upper and lower ends of the display unit 2 has been described. However, the type and arrangement of the light sources are not limited thereto. For example, as shown in FIG. 9a, an LED direct type backlight system in which LEDs are arranged in a matrix on the back of the display unit, or a lamp direct type in which lamps such as fluorescent tubes are arranged at predetermined intervals as shown in FIG. 9b. The backlight method may be used.

  In the first embodiment of the present invention, the configuration in which two light sources A112 and B113 are provided as light sources has been described. However, the present invention is not limited to this. For example, N light sources (N is an integer of 2 or more) may be provided as light sources. In this case, the display region and the kth display region irradiated with only the mth light source (m is an integer of 1 to N) are used. The light source (k is an integer from 1 to (N-1)) and the (k, k + 1) th display area irradiated with the (k + 1) th light source are divided into light sources, and the light source controller 120 turns on the first light source to the Nth light source. -When the turn-off is controlled and the moving image area is included in the (k, k + 1) th display area, the kth light source and the (k + 1) light source are turned off simultaneously during the scanning period of the moving image area. There is an effect.

  FIG. 10 is a flowchart of light source control when one moving image area exists in the apparatus 1.

  In step 1 (S1), an image is displayed on the video display panel 111 based on the video signal, and the process proceeds to step 2 (S2).

  In step 2 (S2), the moving image detection unit 122 detects a moving image region, outputs information on the detected moving image region to the presence region determination unit 123, and proceeds to step 3 (S3).

  In step 3 (S3), the presence area determination unit 123 determines the relationship between the detected moving image area, the area SA, the area SB, and the overlap area SD, and outputs an existence area determination signal to the PWM control unit 125. If the moving image area is included in the overlapping area SD, the process proceeds to step 4 (S4). If not included, the process proceeds to step 5 (S5).

  In step 4 (S4), the PWM control unit 125 generates the black insertion phase signals A and B having the same value and outputs the black insertion phase signals A and B to the PWM pulse generation unit 126, so that the moving image region included in the overlap region SD is scanned during the scanning period. The light source A112 and the light source B113 are turned off simultaneously. Thereafter, the process proceeds to step (S2) to perform processing for the next frame.

  On the other hand, in Step 5 (S5), the PWM control unit 125 generates the black insertion phase signals A and B individually based on the existence region determination signal and outputs them to the PWM pulse generation unit 126, so that the light source A112 and the light source B113. Are controlled individually. Thereafter, the process proceeds to step (S2) to perform processing for the next frame.

(Embodiment 2)
FIG. 11 is a diagram illustrating a driving waveform of the light source when the object M8 moving in the right direction while being enlarged is displayed.

  As shown in FIG. 11, since the size of the object M8 increases while moving in the overlapping area SD, moving image blur cannot be suppressed only by performing black insertion for a predetermined black insertion period T. Therefore, the black insertion period T0 (> T) is extended in accordance with the size of the object M8.

  However, if the black insertion period is simply extended, the luminance decreases. Therefore, by changing the peak values (current values) of the drive waveforms for the light sources A and B to the peak values HA and HB that are higher than the predetermined peak value H, a decrease in luminance is suppressed. Note that since there is a physical limit to the improvement in luminance by increasing the peak value, the period corresponding to the overlap region SD may be maximized as the black insertion period.

  In this way, by extending the black insertion period and increasing the peak value of the drive waveform of the light source, even when the object becomes large during movement, crosstalk due to irradiation from multiple light sources can be prevented, and video blurring can be prevented. In addition, it is possible to realize a high-quality image display without a decrease in luminance.

  Hereinafter, the configuration of the apparatus 200 related to the black insertion period extension process will be described with reference to FIG.

  FIG. 12 is a configuration diagram of the apparatus 200.

  As shown in FIG. 12, the display unit 210 of the apparatus 200 includes a video display panel 211 that displays video, a light source A 212 that irradiates the video display panel 211, and a light source B 213, and controls the light source A 212 and the light source B 213. The light source controller 220 is connected. The light source control unit 220 includes a moving image region size calculation unit 230, a light source luminance setting unit 221, a moving image detection unit 222, an existing region determination unit 223, a moving image priority determination unit 224, a PWM control unit 225, and a PWM pulse generation unit 226. A black insertion period limiter 231 is provided.

  Here, configurations other than the moving image region size calculation unit 230 and the black insertion period limiter unit 231 have the same functions as the corresponding configurations of the apparatus 1 described in FIG.

  The moving image area size calculation unit 230 calculates the size of the detected moving image area when it is determined that the detected moving image area is included in the overlapping area SD based on the presence area determination signal, and the moving image area size calculation unit 230 determines the moving image area size according to the calculation result. The black insertion period is output to the black insertion period limiter unit 231.

  The black insertion period limiter 231 sets the value as it is when the black insertion period output by the moving image area size calculation unit 230 is smaller than the period corresponding to the overlapping area SD, and sets the black insertion period as the overlapping area SD when larger. A value limited to a period corresponding to is output to the PWM control unit 225.

  The PWM control unit 225 generates the black insertion phase signals A and B based on both the information on the black insertion target moving image area output from the moving image priority determination unit 224 and the black insertion period output from the black insertion period limiter unit 231. Generated and output to the PWM pulse generator 226.

  The PWM pulse generation unit 226 controls turning on / off of the light source A 212 and the light source B 213 based on the black insertion phase signals A and B output from the PWM control unit 225. The black pulse indicated by the black insertion phase signals A and B When the insertion period exceeds the predetermined black insertion period T, the peak values of the drive waveforms for the light sources A and B are changed to peak values HA and HB higher than the predetermined peak value H.

  In the second embodiment, the control of the black insertion period and the drive waveform for the object M8 moving in the right direction while increasing in size has been described. However, the black insertion period and the drive waveform in the second embodiment are described. The control is applicable not only to an object that moves while increasing in size, but also to the objects M1 to M3, M6, and M7 in FIGS.

  The image display device and the image display method of the present invention can be applied to an image display device including a plurality of light sources that irradiate a display screen.

1,100,200,300,400,500,600 Image display device (this device)
2,110,210 Display unit 3 Holding table 4 Light guide plate 120, 220 Light source control unit 121, 221 Light source luminance setting unit 122, 222 Video detection unit 123, 223 Presence area determination unit 124, 224 Video priority determination unit 125, 225 PWM control unit 126, 226 PWM pulse generation unit 111, 211 Video display panel 230 Video area size calculation unit 231 Black insertion period limiter unit 112, 212 Light source A
113,213 Light source B

Claims (7)

Display means for displaying an image;
A first light source and a second light source for illuminating the display means;
Light source control means for controlling on / off of the first light source and the second light source;
A moving image region extracting unit that extracts a moving image region including a moving image in the display region of the display unit;
The display area includes a first display area irradiated only by the first light source, a second display area irradiated only by the second light source, and a third display area irradiated by the first light source and the second light source. Consisting of
When the moving image area is included in the third display area, the light source control unit turns off the first light source and the second light source during a scanning period of the moving image area. When an area where the moving image in the moving image area and the first display area overlap is a first overlapping area, and an area where the moving image in the moving image area overlaps the third display area is a third overlapping area,
When the size of the third overlapping region is greater than or equal to the size of the first overlapping region, the light source control unit turns off the first light source and the second light source during the moving image scanning period in the moving image region. And
2. The image according to claim 1, wherein when the size of the third overlapping region is smaller than the size of the first overlapping region, the light source control unit turns off the first light source during a scanning period of the first overlapping region. Display device. When the scanning period of the moving image area exceeds the extinguishing period set in advance for the first light source and the second light source, the light source control means performs the first light source and the outside of the moving period of the moving image area. The image display device according to claim 1, wherein the intensity of the second light source is set higher than a predetermined intensity. A moving image area characteristic detecting means for detecting a moving image characteristic in the moving image area extracted by the moving image area extracting means;
The first moving image area extracted by the moving image area extracting means is included in the third display area, the second moving image area extracted by the moving image area extracting means is included in the first display area, and the moving image area characteristics A first priority based on the characteristics of the moving image in the first moving image area detected by the detecting means, and a second priority based on the characteristics of the moving image in the second moving image area detected by the moving image area characteristic detecting means; When the first priority is equal to or higher than the second priority, the light source control means turns off the first light source and the second light source during the scanning period of the first moving image area, When the first priority is lower than the second priority, the light source control unit turns off the second light source during the scanning period of the first moving image area, and the scanning time of the second moving image area. The light source control means is the first light source. The image display apparatus according to claim 1, wherein turning off. When the characteristic is luminance, the priority based on the luminance increases as the luminance increases, and when the characteristic is movement, the priority based on the movement increases as the movement becomes faster. 5. The image display device according to claim 4, wherein the priority based on the amount of high frequency component increases as the amount of high frequency component increases. Display means for displaying an image;
N (N is an integer of 2 or more) first light source to N light source for illuminating the display means;
Light source control means for controlling turning on / off of the N first light sources to the Nth light source;
A moving image region extracting unit that extracts a moving image region including a moving image in the display region of the display unit;
The display area is irradiated with only the mth light source (m is an integer from 1 to N), the kth light source (k is an integer from 1 to (N-1)), and the (k + 1) light source. The (k, k + 1) th display area,
When the moving image area is included in the (k, k + 1) th display area, the light source control unit turns off the kth light source and the (k + 1) light source during the scanning period of the moving image area. . A display step for displaying the image on the display means;
A light source control step for controlling turning on / off of N (N is an integer of 2 or more) first light source to N light source that irradiates the display means;
A moving image region extracting step of extracting a moving image region including a moving image in the display region of the display means;
When the moving image area is included in the display area irradiated with the kth light source (k is an integer from 1 to (N−1)) and the (k + 1) light source, the light source control is performed during the scanning period of the moving image area. An image display method for turning off the kth light source and the (k + 1) th light source in the step.

Images