JP2010026045A - Display device, display method, program, and recording medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To control display brightness of a display device to be optimal for a viewer. <P>SOLUTION: The display device has a display screen and includes: a horizontal viewing angle calculation means which calculates a horizontal viewing angle to the display screen of the viewer viewing the display screen; and a brightness control means which controls a maximum display brightness of the display screen on the basis of the calculated horizontal viewing angle. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a display device having a display screen, and more particularly to a display device, a display method, a program, and a recording medium that adjust display luminance of the display screen.

Conventionally, a method has been proposed in which a display device measures the distance to a viewer and controls screen display brightness in accordance with the distance.
As means for measuring the viewer's distance, for example, a technique using an infrared LED or an ultrasonic sensor has been proposed.

  For example, a television equipped with an infrared LED irradiates the viewer with the infrared LED and measures the distance of the viewer based on the reflected light from the viewer. Such a technique is disclosed in Patent Documents 1 and 2.

  In Patent Document 1, specifically, in a color television, a television receiver main body or an attached remote control transmitter is provided with an infrared or ultrasonic distance sensor, and a television receiver is provided according to the detected distance. A technique for adjusting an image to be projected is disclosed. As a result, the video is adjusted so as to have an image quality optimal for the viewer.

Patent Document 2 discloses a technique for detecting a distance and adjusting the volume of a television receiver, the brightness of an image, or the like according to the detected distance. Thereby, even if the position of the viewer from the television receiver changes, the viewer can view comfortably.
JP 4-192762 (published July 10, 1992) JP 4-132487 (published May 6, 1992)

  However, the technique of Patent Document 1 does not consider how it is appropriate to control the display luminance based on the relationship between the human visual characteristics and the viewer distance measurement data. The optimal display brightness for each viewer depends on the angle of view, the viewer's age, ambient brightness, video brightness, and even the viewer's preference, in addition to the distance, the TV receiver screen size. To do. However, the technique of Patent Document 1 discloses only a method for measuring the distance between the television viewer and the television receiver and a method for adjusting display luminance and the like based only on the measured distance. Therefore, the technique of Patent Document 1 has a problem that it is impossible to obtain an optimal display luminance for the viewer.

  Also, the technique of Patent Document 2 only discloses a method of adjusting display luminance or the like based only on the distance. Therefore, there is a problem similar to that of Patent Document 1.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a display device, a display method, a program, and a recording medium that control the maximum display brightness so as to obtain an optimum display brightness for the viewer. It is to provide.

(Display device)
In order to solve the above problems, a display device according to the present invention provides
A display device having a display screen,
An angle of view calculating means for calculating a horizontal angle of view of the viewer viewing the display screen with respect to the display screen;
Brightness control means for controlling the maximum display brightness of the display screen based on the calculated horizontal angle of view.

  According to said structure, this display apparatus has a display screen. The display screen is, for example, a television screen that displays a general broadcast video.

  In addition, the display device includes an angle-of-view calculating unit that calculates a horizontal angle of view of the viewer who views the display screen with respect to the display screen. Thereby, it is possible to detect how much the viewer is viewing the display screen by forming a horizontal angle of view with respect to the display screen. When the viewer is not in the front direction of the display screen, is away from the display screen, or is close to the display screen, the horizontal angle of view is different. Regardless of such a case, if the display device always displays an image on the display screen with a constant display luminance, the display may not be appropriate. In particular, excessive display brightness promotes visual fatigue and consumes wasted power.

  Therefore, the display device further includes luminance control means for controlling the maximum display luminance of the display screen based on the calculated horizontal angle of view. Thereby, it is possible to adjust to the optimal display brightness for the viewer according to the horizontal angle of view. In the present invention, the maximum display brightness is, for example, the upper limit brightness determined by the brightness of the backlight. For example, in the case of 256 gradations with gradation levels ranging from 0 to 255, the upper limit luminance is 255 levels. That is, the luminance control means adjusts the backlight light to an optimum level based on the horizontal angle of view, for example.

  Therefore, this display device has an effect of comfortably viewing the video regardless of the direction and distance of the viewer with respect to the display screen. Thereby, it is possible to reduce visual fatigue due to excessive display luminance, which has been a problem in the past. Furthermore, in order to reduce extra display luminance, there is an additional effect of reducing power consumption.

(Distance measuring means)
Moreover, the display device according to the present invention includes:
A distance measuring means for measuring a distance from the display screen of the viewer;
Preferably, the angle of view calculation means calculates the horizontal angle of view based on the distance.

  According to said structure, this display apparatus is provided with the distance measurement means which measures the distance from a viewer's display screen. Thereby, it is possible to accurately measure the distance of the viewer from the display screen. Furthermore, the angle of view calculation means calculates a horizontal angle of view based on the measured distance. Thereby, it is possible to calculate a horizontal angle of view. Therefore, this display device can appropriately control the maximum display luminance.

(Position measuring means)
Moreover, the display device according to the present invention includes:
A position measuring means for measuring a relative position of the viewer with respect to the display screen;
Preferably, the angle of view calculation means calculates the horizontal angle of view based on the relative position.

  According to said structure, this display apparatus is provided with the position measurement means to measure a relative position with respect to a viewer's display screen. Thereby, it is possible to accurately measure the relative position of the viewer with respect to the display screen. Furthermore, the angle of view calculation means calculates a horizontal angle of view based on the measured relative position. Thereby, an accurate horizontal field angle can be calculated. Therefore, this display device can appropriately control the maximum display luminance.

(Brightness control means)
The brightness control means further includes:
Controlling the maximum display brightness of the display screen so that the maximum display brightness is a value obtained by multiplying the horizontal angle of view exponentially based on an index β and a constant K. Is preferred.

  According to the above configuration, the brightness control means displays the display screen so that the maximum display brightness is a value obtained by multiplying the horizontal angle of view exponentially based on the index β and the constant K. Controls the maximum display brightness. As a result, the present display device can determine the maximum display luminance if the values of the horizontal angle of view, the exponent β, and the constant K are known.

(Dating method)
Moreover, the display device according to the present invention includes:
Provided with age input means for receiving the viewer's age input,
The luminance control means preferably changes the value of the constant K according to the age.

  According to said structure, this display apparatus is provided with the age input means which receives the input of a viewer's age. This makes it possible to acquire age information input by the viewer. Further, the luminance control means changes the value of the constant K in accordance with the input age information. Thereby, this display apparatus can be adjusted to the maximum display luminance according to the viewer's age. That is, it is possible to perform control so that the maximum display luminance is suitable for visual characteristics that change depending on the age of the viewer.

(Constant input means)
Moreover, the display device according to the present invention includes:
Preferably, constant input means for receiving input of the values of the constant K and the index β is provided.

  According to said structure, this display apparatus is provided with the constant input means which receives the input of the value of the constant K and the said index | exponent (beta). Thereby, the viewer can change the values of the constant K and the index β according to the preference. Therefore, it is possible to adjust the display luminance according to the viewer's preference.

(Average value of maximum display brightness)
In the display device according to the present invention,
When there are multiple viewers,
The brightness control means includes
It is preferable to control the maximum display brightness of the display screen based on the average value of the maximum display brightness for each viewer.

  According to said structure, a brightness | luminance control means controls the maximum display brightness of a display screen based on the average value of each maximum display brightness with respect to each viewer. Specifically, when there are a plurality of viewers in front of the display screen, first, the maximum display brightness corresponding to the horizontal image quality for each viewer is obtained. Next, the average value of each maximum display brightness is set as the maximum display brightness of the display screen. Thereby, it is possible to set the maximum display luminance appropriate for all viewers.

(Display method)
In addition, the display method according to the present invention solves the above-described problems,
A display method executed by a display device having a display screen,
An angle-of-view calculation step of calculating a horizontal angle of view of the viewer viewing the display screen with respect to the display screen;
And a luminance control step for controlling the maximum display luminance of the display screen based on the calculated horizontal angle of view.

  According to said structure, there exists an effect | action and effect similar to the display apparatus mentioned above.

(Program and recording medium)
The display device according to the present invention may be realized by a computer. In this case, a program for realizing the display device in the computer by operating the computer as each of the above-described means and a computer-readable recording medium recording the program also fall within the scope of the present invention.

  As described above, the display device according to the present invention calculates the horizontal angle of view of the viewer with respect to the display screen, and controls the maximum display luminance based on the horizontal angle of view. Thereby, it is possible to adjust the display brightness to be optimal for the viewer according to the horizontal angle of view. Therefore, there is an effect that the video can be comfortably viewed regardless of the direction and distance of the viewer with respect to the display screen.

  Embodiments of a display device of the present invention will be described below with reference to FIGS.

(Configuration of display device 1)
First, the configuration of the display device 1 according to the present invention will be described with reference to FIG.

  FIG. 1 is a block diagram showing a main configuration of the display device 1. As shown in FIG. 1, the display device 1 includes a light source 2, a display unit 3, an infrared LED 4, a viewer distance sensor 5, a viewer distance measurement unit 6 (distance measurement means), and a horizontal field angle calculation unit 7 (field angle). Calculation unit), input unit 8 (year input unit, constant input unit), maximum luminance calculation unit 9 (luminance control unit), light source output setting unit 10 (luminance control unit), and viewer position measurement unit 11 (position measurement unit) ). As shown in FIG. 1, the display unit 3 is disposed on the light source 2. The light source here is a backlight. The display device 1 will be described on the assumption that it is a television that outputs video received from terrestrial digital or terrestrial analog broadcast to the display unit 3. However, the display device 1 is not limited to this. Any other type of display device may be used as long as the user can visually grasp what is displayed on the display unit 3 of the display device 1. The viewer distance sensor 5 is a conventional distance sensor such as PSD (Position Sensitive Light Detector). In the present embodiment, an infrared LED is used, but other techniques may be used as long as the distance of the viewer can be specified. For example, an ultrasonic sensor may be used. Here, there is no particular limitation. The viewer distance measuring unit 6 and the viewer position measuring unit 11 are provided in the center of the screen of the display unit 3. Detailed processing of each part of the display device 1 will be described later.

(Processing of display device 1)
Next, processing of the display device 1 will be described below with reference to FIG. Moreover, in the following description, it demonstrates on the assumption that the surface (display screen) which displays the image | video of the display part 3 of the display apparatus 1 and the viewer are facing.

  FIG. 2 is a flowchart showing the overall processing flow of the display device 1. As shown in FIG. 2, in the display device 1, first, the infrared LED 4 irradiates the viewer (step S1). Subsequently, the viewer distance sensor 5 detects the incident point of the light of the infrared LED 4 reflected from the viewer (step S2), and outputs the detected incident point to the viewer distance measuring unit 6.

  The viewer distance measuring unit 6 calculates the distance from the viewer distance measuring unit 6 to the viewer based on the input incident point (step S3). Subsequently, the calculated viewer distance information is output to the horizontal angle-of-view calculation unit 7.

(Horizontal angle of view)
Here, the horizontal angle of view will be described below with reference to FIG. FIG. 3 is a diagram showing a horizontal angle of view. As shown in FIG. 3, the horizontal angle of view referred to in the present embodiment connects the viewer's eyes 30 who see the display unit 3 and the right end of the display unit 3 when the upper end of the display unit 3 is looked down from directly above. An angle 31 formed between the line and a line connecting the eye 30 and the left end of the display unit.

  In the present embodiment, the process for calculating the horizontal angle of view based on the distance calculated in S3 will be described below, but the method for calculating the horizontal angle of view is not limited to this. For example, it is possible to calculate the horizontal angle of view based on the relative position of the viewer with respect to the viewer position measuring unit 11. The calculation of the horizontal angle of view based on the relative position will be described later.

  The horizontal angle of view calculation unit 7 calculates the horizontal angle of view based on the input distance information (step S4). The calculation of the horizontal angle of view based on the distance will be described later. Further, the calculated horizontal angle of view is output to the maximum luminance calculation unit 9.

  After S4, when the viewer inputs his / her age, the input unit 8 accepts the input and outputs information on the input age to the maximum luminance calculation unit 9 (step S5). At this time, the input unit 8 is assumed to be built in a remote controller attached to the display device 1 or provided in the display device 1 main body.

(Relationship between horizontal angle of view and preferred display brightness)
Here, the relationship between the horizontal angle of view and the display luminance preferable for the viewer with respect to the horizontal angle of view will be described. This relationship is clarified by the experiment below.

  First, the instrument used in the experiment will be described. The experiment was performed using a liquid crystal television that was modified so that the subject (viewer) could directly control the display brightness to any value. The screen size of the liquid crystal television is 65 inches. The television main body has a built-in luminance control means and does not use a remote control. Specifically, the said means will adjust the backlight intensity of a television, if the adjustment instruction | indication from a test subject is received.

  Next, the subject will be described. There are two groups of subjects. One is a group composed of 26 young people, and the average age of 26 young people is 22.6 years old. The other is a group composed of 26 elderly people, and the average age of 26 elderly people is 71 years old. The experiment with subjects of different ages is to take into account differences in visual characteristics caused by age. Details of differences in visual characteristics will be described later together with experimental results.

  Next, the ambient environment during the experiment will be described. The brightness of the room during the experiment was adjusted so that the screen illuminance near the center of the TV screen was 100 lux (lx). 100 lux is the average TV screen illuminance in a general household.

  In the experiment, the display brightness of the sample video displayed on the television was adjusted so that the test subject would have the brightness considered optimal for the test subject using the above-described means.

  The sample videos are selected from general broadcast videos, and are 25 types of videos with different average brightness levels. The display time of each video is 5 to 20 seconds. The test subject is set to display luminance that can be determined to be most preferable for each video.

  The horizontal angle of view was recorded while changing the viewing distance. That is, the horizontal angle of view when the viewer moves away from the television or approaches the television is recorded.

  The above experimental results will be described below with reference to FIG. FIG. 4 is a graph showing the relationship between the horizontal field angle and the display luminance preferable for the viewer with respect to the horizontal field angle.

Specifically, FIG. 4 shows a preferable maximum obtained by adjusting the luminance of 25 types of images set by 26 subjects with respect to the horizontal angle of view α for each of the two groups having different ages described above. The average value of the luminance Lp (Luminance Peak) (cd / m ² ) is plotted. A line 41 connecting the plot values is data of an experimental result of the elderly group. On the other hand, the line 40 is data of the experimental results of the youth group. From these results, it has been found that a certain relationship is established between the horizontal angle of view α and the preferred display luminance.

  A certain relationship indicated by the experimental results is expressed by the following equation (Equation 1).

  As shown in Expression 1, the maximum display brightness Lp is a value obtained by multiplying the constant K by a value obtained by changing the horizontal angle of view α exponentially based on the index β.

  The line 41 in FIG. 4, that is, the experimental result of the elderly group is expressed by the following formula (Formula 2).

  On the other hand, the line 40 in FIG. 4, that is, the experimental result of the youth group, is expressed by the following equation (Equation 3).

(Difference in visual characteristics by age)
At this time, K is considered to be a constant reflecting a difference in visual sensitivity depending on age. The value of the constant K of the elderly group obtained from this experiment is 466.25. On the other hand, the constant K of the young group is 369. Thus, the value of the constant K to be used differs between the elderly and the young. This is thought to be because human vision suddenly declines after middle age. For this reason, for example, it is considered that there is no difference in visual perception between a 15-year-old or 30-year-old viewer and a young person in this experiment.

  Therefore, for example, it is desirable to set the same value as that for young people to the constant K for viewers up to the 40s, and to set the same value as the constant K for viewers after the 50s. It is further desirable to set the constant K more strictly according to the age. For example, the average value of the constant K for young people and the constant K for elderly people is applied to viewers in their 50s, and the value of the constant K of elderly people is applied to viewers in their 60s. Can be considered.

  In this way, by making it possible to change the value of K according to the age of the viewer, it is possible to control the display brightness to be appropriate in consideration of age-specific visual characteristics.

  In addition, the coefficient β in Equation 1 is considered to be a coefficient that reflects general visual characteristics of humans. The value of coefficient β of the elderly group obtained from this experiment is −0.2328, while the value of coefficient β of the young group is −0.2263. The value of β may be changed according to age or the same.

  In addition, the values of the constant K and the coefficient β are considered to change depending on the video content, lighting conditions, and the like. Furthermore, it is considered that differences in personal preference with respect to display brightness greatly affect these values. For this reason, it is more preferable that it can be adjusted to an appropriate value according to the preference of the viewer.

  Therefore, the viewer may input the viewer age and set the constant K and the coefficient β to arbitrary values (step S5). When the constant K and the coefficient β are input in addition to the viewer age, the input unit 8 outputs information on the age, the constant K, and the coefficient β to the maximum luminance calculation unit 9. In S5, when arbitrary values of K and β are not set, the maximum luminance calculation unit 9 refers to the values of K and β by age prepared in advance according to the input age of the viewer.

  As described above, if the viewer's horizontal angle of view and age are known, the preferred maximum display luminance with respect to the horizontal angle of view can be obtained from Equation 1.

  In the processing so far, the maximum luminance calculation section 9 has been inputted with information on the viewer's horizontal angle of view and age. The maximum luminance calculation unit 9 is further input with a constant K and a coefficient β that are arbitrarily set by the viewer. The maximum luminance calculation unit 9 calculates the optimum maximum luminance for the viewer by substituting the horizontal angle of view, the age information, the constant K, and the coefficient β into the above-described equation 1 (step S6).

  After S6, the maximum luminance calculation unit 9 outputs the calculated maximum luminance to the light source output setting unit 10, and at the same time, determines whether the maximum luminance for all viewers has been output (step S7). All viewers are one or a plurality of viewers who view the video displayed on the display device 1.

  Here, calculation of the horizontal angle of view in each case when there is one viewer and when there are a plurality of viewers will be described.

(When there is one viewer)
In this embodiment, when there is one viewer, the horizontal angle of view is calculated based on the distance from the viewer distance measuring unit 6 to the viewer.

  The horizontal angle of view can be roughly calculated if the distance between the television receiver and the viewer is known. Therefore, the horizontal angle of view can be obtained based on the distance data measured using the infrared LED 4 or the viewer distance sensor 5 used in the present embodiment. Further, the distance data may be configured so that the viewer can directly input the data using a remote controller.

  The distance here will be described using, for example, the distance between the TV and the viewer, which is recommended in high-vision TV viewing. The recommended distance is 3H, ie, three times the height (H) of the TV screen.

  When a viewer located at a distance of 3H from the TV views the TV from the front (that is, a direction perpendicular to the TV screen), the horizontal angle of view α is 33.0 degrees. On the other hand, the horizontal angle of view α when a viewer located at the same distance views the video by shifting 30 degrees from the front to the right or left is 29.4 degrees. The difference between these two α values is slight.

  Further, a value obtained by substituting these two α values into the above-described formula 1 in the case of an elderly person will be considered.

By substituting the above two values of α into Equation 2 described above, the respective maximum display luminance Lp is calculated. When α is 33 degrees, Lp is 207 cd / m ² . On the other hand, when α is 29.4 degrees, Lp is 212 cd / m ² (in the calculation result, the decimal part is rounded off).

  Thus, for viewers that form different horizontal angles of view at the same distance, the preferred maximum display brightness to be controlled may be slightly different. Therefore, if the distance between the TV screen and the viewer is known, it can be said that the display luminance can be controlled with almost no problem.

  When calculating the horizontal angle of view based only on the distance, the horizontal angle of view is calculated by the following equation (Equation 4). At this time, the horizontal width of the TV screen is W and the viewing distance is d.

(When there are multiple viewers)
On the other hand, when there are a plurality of viewers, the horizontal angle of view is calculated based on the viewer's relative position with respect to the viewer position measuring unit 11.

  In reality, the viewer does not always watch at a distance of 3H. Also, the number of viewers is not always one. If the horizontal angle of view is calculated based only on the distance of the viewer from the TV screen when there are a plurality of viewers, a slight error may occur in the horizontal angle of view for each viewer.

  Here, an example in which the distance of 3H is not set as described above and there are a plurality of viewers will be described with reference to FIG. FIG. 5 is a diagram illustrating horizontal angles of view formed by a plurality of viewers located at the same distance from the viewer position measurement unit 11.

  A broken line 50 shown in FIG. 5 is a part of a circumference drawn with a certain distance as a radius around the viewer position measuring unit 11 provided at the center of the display unit 3. As shown in this figure, viewers 51, 52, and 53 are located on the broken line 50. The viewer 51 forms a horizontal angle of view 54. Similarly, the viewer 52 forms a horizontal angle of view 55 and the viewer 53 forms a horizontal angle of view 56, respectively.

  Thus, even if the viewer is located at the same distance from the viewer position measuring unit 11, the horizontal angle of view formed on the display unit 3 is different.

  Therefore, when there are a plurality of viewers, the horizontal angle of view is not simply calculated based on the viewer's distance from the viewer distance measuring unit 6 but is set at the relative position of the viewer with respect to the viewer position measuring unit 11. It is more appropriate to calculate based on this. That is, a more appropriate horizontal angle of view is required, and control can be made to a more appropriate maximum display luminance.

  In the measurement system using infrared rays or ultrasonic waves, it is difficult to measure each distance of the viewer individually. Therefore, when there are a plurality of viewers, the viewer position measuring unit 11 measures the relative positions of the plurality of viewers in the front direction of the display unit 3. Specifically, the viewer position measurement unit 11 measures the positions of a plurality of viewers by image recognition technology using a CCD or CMOS sensor. Therefore, in S4, when there are a plurality of viewers, it is desirable that the horizontal angle-of-view calculating unit 7 calculates the horizontal angle of view based on the information measured by the viewer position measuring unit 11.

  In the case of Yes in S7, the light source output setting unit 10 calculates the average value of all the maximum luminances calculated in S6. That is, the average value of the maximum brightness optimum for each viewer is averaged (step S8).

(Average value of maximum display brightness)
Here, the average of the total value of the maximum luminance will be described with reference to FIG. FIG. 6 is a distribution diagram of the maximum display luminance based on the relative position of the viewer with respect to the television screen, obtained from the data 40 in FIG. Data 40 is a result of a group of young subjects in the above-described experiment. In FIG. 4, it is assumed that the liquid crystal television used in the above-described experiment is disposed at a position where both the X coordinate and the Y coordinate are 0.

  As shown in FIG. 6, it can be seen that the optimum display luminance for the viewer varies depending on the relative position with respect to the liquid crystal television. For example, a description will be given by taking as an example a plurality of viewers whose X coordinate is 300, that is, 3 m away from the screen of the liquid crystal television.

  It is assumed that the viewer A views from the position (X, Y) = (300, 0). On the other hand, it is assumed that the viewer B views from the position (X, Y) = (300, 300). At this time, as shown in the figure, the optimum maximum display luminance for the viewer A is any value greater than 170 and not greater than 180. On the other hand, the optimum maximum display luminance for the viewer B is any value greater than 200 and not greater than 210.

  As described above, if the relative position with respect to the television screen is different, the optimum maximum display luminance is different. Therefore, instead of calculating the average value of the relative position of each viewer and then calculating the horizontal angle of view for that average value, the maximum display luminance based on the horizontal angle of view at each relative position is calculated first, and the average It is desirable to determine the value.

  Therefore, in the present embodiment, as described above, when there are a plurality of viewers, first, the horizontal angle of view for each viewer is calculated, and each maximum display luminance based on the horizontal angle of view is calculated. Then, an average value of each maximum display luminance is obtained. Thereby, it is possible to set the maximum display luminance appropriate for all viewers.

  In the case of No in S7, the display device 1 returns to S4.

  After S8, the light source output setting unit 10 sets the output of the light source based on the calculated average value of the maximum luminance (step S9).

  The display device 1 outputs a light source based on the setting of S9. Thereby, the display apparatus 1 can display an image | video with the optimal display brightness for a viewer.

  As described above, the display device 1 can adjust the display brightness to be optimal for the viewer according to the horizontal angle of view. Therefore, there is an effect that the video can be comfortably viewed regardless of the direction and distance of the viewer with respect to the display screen. Thereby, it is possible to reduce visual fatigue due to excessive display luminance, which has been a problem in the past. Furthermore, in order to reduce extra display luminance, there is an additional effect of reducing power consumption.

  In addition, this invention is not limited to embodiment mentioned above. Those skilled in the art can make various modifications to the present invention within the scope of the claims. That is, a new embodiment can be obtained by combining appropriately changed technical means within the scope of the claims.

(Program and recording medium)
Finally, each block included in the display device 1 may be configured by hardware logic. Alternatively, it may be realized by software using a CPU (Central Processing Unit) as follows.

  That is, the display device 1 includes a CPU that executes instructions of a program that realizes each function, a ROM (Read Only Memory) that stores the program, a RAM (Random Access Memory) that expands the program into an executable format, and A storage device (recording medium) such as a memory for storing the program and various data is provided. With this configuration, the object of the present invention can be achieved by a predetermined recording medium.

  The recording medium only needs to record the program code (execution format program, intermediate code program, source program) of the program of the display device 1 which is software for realizing the above-described functions so as to be readable by a computer. This recording medium is supplied to the display device 1. Thus, the display device 1 (or CPU or MPU) as a computer may read and execute the program code recorded on the supplied recording medium.

  The recording medium that supplies the program code to the display device 1 is not limited to a specific structure or type. That is, the recording medium includes, for example, a tape system such as a magnetic tape and a cassette tape, a magnetic disk such as a floppy (registered trademark) disk / hard disk, and an optical disk such as a CD-ROM / MO / MD / DVD / CD-R. System, a card system such as an IC card (including a memory card) / optical card, or a semiconductor memory system such as a mask ROM / EPROM / EEPROM / flash ROM.

  Further, even if the display device 1 is configured to be connectable to a communication network, the object of the present invention can be achieved. In this case, the program code is supplied to the display device 1 via the communication network. The communication network is not limited to a specific type or form as long as it can supply the program code to the display device 1. For example, it may be the Internet, intranet, extranet, LAN, ISDN, VAN, CATV communication network, virtual private network, telephone line network, mobile communication network, satellite communication network, and the like.

  The transmission medium constituting the communication network may be any medium that can transmit the program code, and is not limited to a specific configuration or type. For example, even in the case of wired lines such as IEEE 1394, USB (Universal Serial Bus), power line carrier, cable TV line, telephone line, ADSL (Asymmetric Digital Subscriber Line) line, infrared rays such as IrDA and remote control, Bluetooth (registered trademark), 802.11 It can also be used by radio such as radio, HDR, mobile phone network, satellite line, terrestrial digital network. The present invention can also be realized in the form of a computer data signal embedded in a carrier wave in which the program code is embodied by electronic transmission.

  The present invention can be widely used as a display device having a display screen. For example, it can be realized as a liquid crystal television.

It is a block diagram which shows the principal part structure of the display apparatus 1 which concerns on this invention. It is the flowchart which showed the flow of the whole process of the display apparatus 1 which concerns on this invention. It is the figure which showed the horizontal angle of view. It is the graph which showed the relationship between a horizontal view angle and the display brightness preferable for the viewer with respect to a horizontal view angle. It is a figure which shows the horizontal view angle which several viewers located in the same distance from the viewer position measurement part 11 which concerns on this invention form. It is the distribution map of the maximum display brightness | luminance based on the relative position of the viewer with respect to the television screen calculated | required from the data 40 in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Display apparatus 2 Light source 3 Display part 4 Infrared LED
5 Viewer distance sensor 6 Viewer distance measuring unit (distance measuring means)
7 Horizontal angle of view calculation unit (field angle calculation means)
8 Input part (year input means, constant input means)
9 Maximum display brightness calculator (Brightness control means)
10 Light source output setting unit (luminance control means)
11 viewer position measuring unit (position measuring means)
30 eyes 31, 54, 55, 56 Horizontal angle of view 40, 41 Data 50 Dashed lines 51, 52, 53 Viewers

Claims (10)

A display device having a display screen,
An angle of view calculating means for calculating a horizontal angle of view of the viewer viewing the display screen with respect to the display screen;
A display device comprising: brightness control means for controlling the maximum display brightness of the display screen based on the calculated horizontal angle of view. A distance measuring means for measuring a distance from the display screen of the viewer;
The display device according to claim 1, wherein the angle of view calculation unit calculates the horizontal angle of view based on the distance. A position measuring means for measuring a relative position of the viewer with respect to the display screen;
The display device according to claim 1, wherein the angle of view calculation unit calculates the horizontal angle of view based on the relative position. The brightness control means includes
Controlling the maximum display brightness of the display screen so that the maximum display brightness is a value obtained by multiplying the horizontal angle of view exponentially based on an index β and a constant K. The display device according to claim 1. Provided with age input means for receiving the viewer's age input,
The display device according to claim 4, wherein the luminance control unit changes the value of the constant K according to the age.   5. The display device according to claim 4, further comprising constant input means for receiving input of the values of the constant K and the exponent β. When there are multiple viewers,
The brightness control means includes
The display device according to claim 3, wherein the maximum display luminance of the display screen is controlled based on an average value of the maximum display luminances for the viewers. A display method executed by a display device having a display screen,
An angle-of-view calculation step of calculating a horizontal angle of view of the viewer viewing the display screen with respect to the display screen;
And a luminance control step for controlling the maximum display luminance of the display screen based on the calculated horizontal angle of view.   A program for operating the display device according to any one of claims 1 to 7, wherein the program causes a computer to function as each of the above means.   A computer-readable recording medium in which the program according to claim 9 is recorded.

Images