JP2013242491A - Display device, gray-scale value correction method, television receiver, program, and recording medium - Google Patents

Abstract

A display device capable of presenting a user with black with reduced luminance unevenness and color unevenness is provided.
A television 10 according to one aspect of the present invention includes input image data including a gradation value equal to or lower than a predetermined gradation in a predetermined ratio or more, and environmental illuminance is equal to or lower than a predetermined illuminance. A black level correction instruction unit 132 that increases the gradation value according to an angle between the normal direction of the LCD 115 and the direction from the LCD 115 to the remote controller 30, and the backlight 116 so as to cancel the increase in the gradation value. And a backlight control unit 133 that reduces the luminance of the backlight.
[Selection] Figure 1

Description

  The present invention relates to a display device operated by a remote control device and a gradation value correction method for the display device. The present invention also relates to a television receiver provided with a display device, a program for operating a computer as the display device, and a recording medium on which such a program is recorded.

  In recent years, television receivers (TVs) equipped with a liquid crystal panel have been widely used. Also, such a television is generally provided with an LED backlight as a light source of a liquid crystal panel.

  In such a television, there is a problem that light of the backlight leaks from the liquid crystal panel, so-called light leakage occurs. In particular, when black is displayed on the entire liquid crystal panel when the brightness when the user watches the TV is dark, the light leakage becomes conspicuous, and the viewing angle characteristics are deteriorated, the luminance is uneven, and the color is uneven. Etc. will occur.

  In addition, when black is displayed on the entire liquid crystal panel when the television is viewed from an oblique direction, luminance unevenness and color unevenness occur.

  Patent Document 1 includes a viewing angle detection unit that detects a viewing angle with respect to the liquid crystal display element, and a gamma correction unit that performs gamma correction based on gamma correction data selected based on the detection result of the viewing angle detection unit. A liquid crystal display device is disclosed. As a result, Patent Document 1 realizes a display image without a decrease in contrast and black-and-white reversal phenomenon even when viewing from a direction deviated from the front of the liquid crystal display element.

Japanese Patent Laid-Open No. 10-301092 (published on November 13, 1998)

  However, although the liquid crystal display device described in Patent Document 1 can prevent a decrease in contrast and a black-and-white reversal phenomenon, there is still a problem that black color unevenness represented by a displayed image cannot be reduced. It was.

  The present invention has been made in order to solve the above-described problems, and a main object thereof is to provide a display device capable of presenting a user with black with reduced luminance unevenness and color unevenness.

  In order to solve the above-described problem, a display device according to an aspect of the present invention is a display device that is operated by a remote control device, and includes an illuminance detection unit that detects ambient illuminance, a normal direction of the display, An angle detection means for detecting an angle formed in a horizontal direction with respect to the direction of the remote control device with the display as a base point, and the input image data includes a gradation value equal to or less than a predetermined gradation in the input image data. And when the ambient illuminance is less than or equal to a predetermined illuminance, a gradation value correcting means for increasing the gradation value below the predetermined gradation according to the angle, and a gradation by the gradation value correcting means. Backlight control means for reducing the brightness of the backlight so as to offset the increase in the tone value is provided.

  A gradation value correction method for a display device according to one aspect of the present invention is a gradation value correction method for a display device operated by a remote control device, and includes an illuminance detection step for detecting ambient illuminance and a display method. An angle detection step for detecting an angle formed in a horizontal direction between the line direction and the direction of the remote control device based on the display; and a gradation value equal to or less than a predetermined gradation in the input image data A gradation value correction step for increasing a gradation value below the predetermined gradation according to the angle when the ambient illuminance is less than or equal to the predetermined illuminance; and the gradation value correction And a backlight control step for reducing the luminance of the backlight so as to offset the increase in the gradation value in the step.

  According to the above configuration, the gradation value correcting unit includes the case where black, which is a color represented by a gradation equal to or lower than the predetermined gradation, is included in the input image data at a predetermined ratio or more. Correction for increasing the gradation below the predetermined gradation according to the angle is performed. Here, since the remote control device is operated by a user, the angle formed along the horizontal direction between the normal direction of the display and the direction of the remote control device based on the display is the normal line of the display. An angle formed along the horizontal direction between the direction and the direction of the user with the display as a base point (also referred to as a user angle) is shown.

  Therefore, the gradation value correcting means can make the black color displayed on the display more uniform according to the angle at which the user views the display. However, it is possible to present black with reduced luminance unevenness and color unevenness. Further, the gradation value correction means does not correct the gradation below the predetermined gradation when the ambient illuminance is bright and luminance unevenness and color unevenness are not noticeable. It is possible to prevent the power required for the reduction from being consumed without permission.

  Further, the backlight control means cancels the luminance increased by the gradation value increased by the gradation value correcting means by lowering the luminance of the backlight, so that the apparent luminance is substantially the same and appropriate. Can be brightness. As a result, the display device can present black with reduced luminance unevenness and color unevenness to the user with appropriate luminance.

  In the display device according to one embodiment of the present invention, it is preferable that an increase in the gradation value by the gradation value correction unit is larger as the angle is larger.

  According to said structure, the said gradation value correction | amendment means can reduce more efficiently the brightness | luminance nonuniformity and color nonuniformity of black which become conspicuous as the said angle becomes large.

  In the display device according to one embodiment of the present invention, it is preferable that the increase in the gradation value by the gradation value correction unit is larger as the ambient illuminance is lower.

  According to said structure, the said gradation value correction | amendment means can reduce more efficiently the brightness | luminance nonuniformity and color nonuniformity of black which become conspicuous as the said surrounding illumination intensity becomes low.

  Further, in the display device according to one aspect of the present invention, the remote control device includes a plurality of light emitting units, and the display device includes an acquisition unit that acquires information indicating distances between the plurality of light emitting units. Identifying means for identifying the plurality of light emitting units from image data obtained by imaging the remote control device, information indicating the distance between the plurality of light emitting units acquired by the acquiring means, and the identification Distance calculating means for calculating the distance from the display to the remote control device based on the plurality of light emitting units identified by the means, and increasing the gradation value by the gradation value correcting means The minute is preferably larger as the distance from the display to the remote control device is larger.

  According to said structure, the said gradation value correction | amendment means can reduce more efficiently the brightness | luminance nonuniformity and color nonuniformity of black which become conspicuous as the distance from the said display to the said remote control apparatus becomes long. .

  The increase in the gradation value by the gradation value correcting means is preferably larger as the average luminance level value is smaller.

  According to the above configuration, the gradation value correcting unit is configured to increase the black luminance unevenness and the color as the value of the average luminance level decreases, that is, as the color of the entire image represented by the input image data becomes darker. Unevenness can be reduced more efficiently.

  Note that a television receiver including each unit of the display device is also included in the scope of the present invention.

  The object of the present invention can also be achieved by a program for causing a computer to operate as the recording / playback apparatus. And not only such a program itself but the computer-readable recording medium on which such a program is recorded is also contained under the category of the present invention.

  In order to solve the above-described problem, a display device according to an aspect of the present invention is a display device that is operated by a remote control device, and includes an illuminance detection unit that detects ambient illuminance, a normal direction of the display, An angle detection means for detecting an angle formed in a horizontal direction with respect to the direction of the remote control device with the display as a base point, and the input image data includes a gradation value equal to or less than a predetermined gradation in the input image data. And when the ambient illuminance is less than or equal to a predetermined illuminance, a gradation value correcting means for increasing the gradation value below the predetermined gradation according to the angle, and a gradation by the gradation value correcting means. Backlight control means for reducing the brightness of the backlight so as to offset the increase in the tone value is provided.

  A display device gradation value correction method according to an aspect of the present invention is a display device gradation value correction method operated by a remote control device, and includes an illuminance detection step of detecting ambient illuminance, and a display An angle detection step for detecting an angle formed along the horizontal direction between the normal direction of the display and the direction of the remote control device with the display as a base point, and a gradation value equal to or less than a predetermined gradation is set in the input image data A gradation value correcting step for increasing the gradation value below the predetermined gradation according to the angle when the ambient illuminance is less than or equal to the predetermined illuminance, and the gradation And a backlight control step for reducing the luminance of the backlight so as to offset the increase in the gradation value by the value correction means.

  As a result, the gradation value correcting means can make the black displayed on the display more uniform according to the angle at which the user views the display. In contrast, black with reduced luminance unevenness and color unevenness can be presented. In addition, the display device can present black with reduced luminance unevenness and color unevenness to the user with appropriate luminance.

It is a block diagram which shows the outline of a structure of the display system which concerns on one Embodiment of this invention. It is a figure which shows an example of the waveform of the remote control signal transmitted from the remote control which concerns on one Embodiment of this invention. It is a flowchart which shows the flow of the remote control signal transmission process in the remote control which concerns on one Embodiment of this invention. It is a figure which shows typically the remote control contained in the image data imaged with the camera in the display system which concerns on one Embodiment of this invention. It is a figure which shows typically the relationship between the television 10 and the remote control 30 in the display system which concerns on one Embodiment of this invention, and a user position. It is a flowchart which shows the flow of the user position detection process in the control part with which the television concerning one Embodiment of this invention is provided. It is a graph which shows the black gradation correction value with respect to each condition referred in the black control part which concerns on one Embodiment of this invention. It is a graph which shows the luminance value with respect to the input gradation referred in the black control part which concerns on one Embodiment of this invention. It is a figure which shows the black image displayed on LCD with which the television concerning one Embodiment of this invention is provided. It is a figure which shows an example of the outline of the other display system which concerns on one Embodiment of this invention. It is a figure which shows typically the smart phone contained in the image data imaged with the camera which concerns on the modification of one Embodiment of this invention. It is a figure which shows an example of the outline of the display system which concerns on the modification of one Embodiment of this invention. It is a flowchart which shows the flow of the radio | wireless signal transmission process in the smart phone which concerns on the modification of one Embodiment of this invention.

  A display system according to an embodiment of the present invention will be described below with reference to FIGS. However, unless otherwise specified, the configuration described in this embodiment is not merely intended to limit the scope of the present invention, but is merely an illustrative example.

  In the present embodiment, since the display device constituting the display system is realized by a television receiver, it is hereinafter referred to as a television. Further, since the remote control device for operating the display device is realized by a remote controller (remote controller), it is hereinafter referred to as a remote controller.

[Configuration of display system]
First, the configuration of the display system according to the present embodiment will be described with reference to FIG. FIG. 1 is a block diagram showing an outline of the configuration of a display system 1 according to the present embodiment.

  As shown in FIG. 1, the display system 1 includes a television (display device) 10, a camera 20, and a remote controller (remote control device) 30.

(TV configuration)
As shown in FIG. 1, the television 10 includes a USB interface 101, a remote control light receiving unit (acquisition means) 102, an illuminance sensor 103, a control unit 104, a digital broadcast receiving unit 105, an HDMI interface 106, an input switching unit 107, and a frame memory 108. A histogram analysis unit 109, an image quality calculation processing unit 110, a video processing unit 111, a detection unit 112, a black control unit 113, an LCD controller 114, an LCD (display) 115, and a backlight 116.

  A USB (Universal Serial Bus) interface 101 is an interface for connecting a USB device to the television 10. Examples of USB devices that can be connected to the television 10 include a camera 20 connected via a USB cable.

  The remote control light receiving unit 102 is a means for receiving a remote control signal transmitted from the remote control 30. The remote control light receiving unit 102 supplies the received remote control signal to the control unit 104.

  The illuminance sensor 103 generates a voltage corresponding to the illuminance around the television 10 (hereinafter also referred to as environmental illuminance). The illuminance sensor 103 supplies the generated voltage corresponding to the environmental illuminance to the control unit 104.

  The control unit 104 controls each unit included in the television 10. Further, each unit of the television 10 is controlled according to a remote control signal received by the remote control light receiving unit 102, image data captured by the camera 20, and a voltage supplied from the illuminance sensor 103.

  Note that the control according to the remote control signal includes control for switching which channel to receive a broadcast program broadcast through, as will be described later. In addition, the control unit 104 notifies the camera 20 of an imaging instruction indicating that the imaging process in the camera 20 is to be executed via the USB interface 101.

  Further, as shown in FIG. 1, the control unit 104 includes an image recognition unit (identification unit) 141, a user position detection unit (angle detection unit, distance calculation unit) 142, and an environmental illuminance determination unit 143.

  The image recognition unit 141 performs image recognition based on the image data input from the camera 20 and supplies the recognition result to the user position detection unit 142. The user position detection unit 142 detects the distance from the television 10 to the user (user distance) and the viewing angle (user angle) of the user with respect to the television 10 based on the recognition result supplied from the image recognition unit 141. Details of processing in the image recognition unit 141 and the user position detection unit 142 will be described later.

  The environmental illuminance determination unit 143 determines the value of the environmental illuminance based on the voltage supplied from the illuminance sensor 103.

  The control unit 104 supplies the user position information indicating the user distance and the user angle detected by the user position detection unit 142 and the environmental illuminance determined by the environmental illuminance determination unit 143 to the black control unit 113.

  The digital broadcast receiving unit 105 is a tuner for receiving a broadcast program broadcast from each broadcast station by terrestrial digital broadcast, satellite broadcast, or the like. The digital broadcast receiver 105 includes, for example, an RF unit that converts a received signal into an analog baseband signal, an ADC unit that converts an analog baseband signal into a digital baseband signal, a demodulator that demodulates an MPEG2 stream from the digital baseband signal, And it can be comprised by the decoding part which decodes a video signal from an MPEG2 stream.

  Note that the control unit 104 may control which channel the digital broadcast receiving unit 105 receives a broadcast program transmitted through.

  An HDMI (High-Definition Multimedia Interface) interface 106 is an HDMI standard interface. The HDMI interface 106 receives content data and CEC commands transmitted from a device connected via an HDMI cable. The HDMI interface 106 transmits a CEC command to a device connected via the HDMI cable.

  The input switching unit 107 receives the broadcast program received by the digital broadcast receiving unit 105 and the content data received by the HDMI interface 106. The input switching unit 107 selects one of the broadcast program and the content data and supplies it to the frame memory 108. Whether the input switching unit 107 selects a broadcast program or content data may be controlled by the control unit 104.

  The frame memory 108 is a storage unit that temporarily stores the broadcast program supplied from the input switching unit 107 or video data (input image data) constituting the content data and audio data. Note that the audio data temporarily stored in the frame memory 108 is read out by an audio processing unit (not shown) and output via a speaker (not shown). Note that the audio processing unit may perform volume adjustment processing, sound quality adjustment processing, and the like on the audio data.

  The histogram analysis unit 109 analyzes the histogram of the input image data temporarily stored in the frame memory 108. The histogram analysis unit 109 supplies the histogram analysis result of the input image data to the image quality calculation processing unit 110 and the detection unit 112.

  Based on the analysis result supplied from the histogram analysis unit 109, the image quality calculation processing unit 110 calculates a value of image quality adjustment processing (image quality adjustment processing value) to be applied to the input image data. The image quality calculation processing unit 110 supplies the calculated image quality adjustment processing value to the video processing unit 111. Note that the image quality adjustment processing refers to, for example, changing at least one of the brightness, sharpness, and contrast of the image represented by the input image data by processing the input image data.

  The video processing unit 111 performs the processing on the input image data read from the frame memory 108 according to the image quality adjustment processing value supplied from the image quality calculation processing unit 110 and the black gradation correction processing value supplied from the black control unit 113. Image quality adjustment processing, black gradation correction processing, scaling processing, and the like are performed. The video processing unit 111 supplies input image data subjected to image quality adjustment processing, black gradation correction processing, scaling processing, and the like to the LCD controller 114.

  Note that the scaling processing means that the size of an image represented by the input image data is similarly enlarged or reduced by processing the input image data. In addition, the control unit 104 may control how the video processing unit 111 changes the size.

  As shown in FIG. 1, the detection unit 112 includes a black area detection unit 121 and an APL (Average Picture Level) detection unit 122.

  Based on the analysis result supplied from the histogram analysis unit 109, the black area detection unit 121 has a gradation value (black level) equal to or lower than a predetermined gradation for one frame of input image data (hereinafter also referred to as a black area). Detect the percentage of. The predetermined gradation can be exemplified by four gradations, for example, but is not particularly limited, and may be three gradations.

  The APL detection unit 122 detects the average luminance level based on the analysis result supplied from the histogram analysis unit 109.

  The detection unit 112 supplies information (black area information) indicating the ratio of the black area detected by the black area detection unit 121 and the average luminance level detected by the APL detection unit 122 to the black control unit 113, respectively. To do.

  The black control unit 113 performs a black gradation correction process and a back process applied to the input image data based on the user information and environmental illuminance supplied from the control unit 104 and the black area information and average luminance level supplied from the detection unit 112. The black level of the input image data and the luminance of the backlight 116 are controlled so that the luminance adjustment processing of the light 116 is linked.

  Further, the black control unit 113 controls the black level of the input image data and the luminance of the backlight 116, and as shown in FIG. 1, the black gradation correction control unit (tone value correction means) 131, the black level A correction instruction unit (tone value correction unit) 132 and a backlight control unit (backlight control unit) 133 are provided.

  The black gradation correction control unit 131 is based on the black area information supplied from the detection unit 112 and the average luminance level, a black level adjustment processing value that is a value of black level adjustment processing applied to the input image data, and A backlight brightness adjustment value for adjusting the brightness of the backlight 116 is calculated. The black gradation correction control unit 131 supplies the calculated black level adjustment processing value to the black level correction instruction unit 132 and supplies the backlight luminance adjustment value to the backlight control unit 133.

  The black level correction instruction unit 132 supplies black level adjustment processing values to the video processing unit 111 to instruct black level adjustment for the input image data. In the present embodiment, the tone value correction means is realized by the black tone correction control unit 131 and the black level correction instruction unit 132.

  The backlight control unit 133 adjusts the luminance of the backlight 116 according to the backlight luminance adjustment value. The backlight control unit 133 adjusts the luminance of the backlight 116 in synchronization with the timing when the input image data whose black level is adjusted by the instruction from the black level correction instruction unit 132 is displayed on the LCD 115 by the LCD controller 114. adjust.

  The LCD controller 114 drives the LCD 115 so that the input image data supplied from the video processing unit 111 is displayed on the LCD 115.

(Camera configuration)
As shown in FIG. 1, the camera 20 includes a lens 201, a CMOS image sensor 202, an encoder 203, a CPU 204, and a USB interface 205.

  The CMOS image sensor 202 captures an image obtained through the lens 201 in accordance with an imaging instruction from the CPU 204 and generates imaging data. The CMOS image sensor 202 supplies the generated imaging data to the encoder 203. The encoder 203 converts the supplied imaging data into image data. Hereinafter, imaging by the CMOS image sensor 202 and conversion of imaging data by the encoder 203 into image data are also simply referred to as imaging processing.

  The CPU 204 controls each part of the camera 20 and also controls the imaging process by the CMOS image sensor 202 and the encoder 203. Further, when the CPU 204 acquires an imaging instruction from the control unit 104 included in the television 10, the CPU 204 notifies the CMOS image sensor 202 of the imaging instruction.

  The USB interface 205 is an interface for connecting a USB device to the camera 20. The camera 20 is connected to the television 10 via a USB cable (not shown) connected to the USB interface.

  In the present embodiment, the imaging by the camera 20 is described as an example of a configuration that is performed according to an instruction from the control unit 104 included in the television 10, but a configuration that is periodically performed regardless of the instruction from the television 10. May be adopted.

(Configuration of remote control)
As shown in FIG. 1, the remote control 30 includes a remote control signal transmission unit 301, an infrared light emitting unit (light emitting unit) 311, and an infrared light emitting unit 312.

  The remote control signal transmission unit 301 transmits a remote control signal via the infrared light emitting units 311 and 312. Examples of the remote control signal include a remote control signal for instructing which channel to receive a broadcast program transmitted through, and a remote control signal for instructing switching on / off of the power supply of the television 10. be able to.

  The remote control signal may be output from the infrared light emitting unit 311, may be output from the infrared light emitting unit 312, or may be output from both the infrared light emitting units 311 and 312.

  Note that the case where the remote controller 30 includes two infrared light emitting units will be described as an example. However, the present embodiment is not limited to this, and for example, a configuration including three or more infrared light emitting units. May be adopted.

[Remote control signal transmission]
Next, a remote control signal transmitted from the remote controller 30 will be described with reference to FIGS.

(Remote control signal)
First, a remote control signal transmitted from the remote controller 30 will be described with reference to FIG. FIG. 2 is a diagram illustrating an example of a waveform of a remote control signal transmitted from the remote controller 30 according to the present embodiment. 2A shows a remote control signal indicating a channel selected by the user, and FIG. 2B shows a remote control signal indicating a distance between the infrared light emitting units 311 and 312 provided in the remote control 30. ing.

  When the remote controller 30 receives a user instruction for selecting any channel by pressing a “2” button (CH2 key) included in a numeric keypad (not shown) provided in the remote controller 30, FIG. As shown, the remote control signal indicating the channel selected by the user is transmitted.

  As shown in FIG. 2A, a remote control signal indicating a channel selected by the user (hereinafter, also referred to as a remote control channel selection signal) includes a custom code indicating the maker of the leader unit and the remote controller 30 and is selected. A CH data code indicating a channel and a stop bit are included.

  The custom code includes a custom code 1 indicating a manufacturer and a custom code 2 obtained by inverting the bit data of the custom code 1. The CH data code includes CH data indicating the selected channel and inverted data obtained by inverting the bit data of the CH data.

  The television 10 can determine the manufacturer of the remote controller 30 by referring to the custom code, and can determine the selected channel by referring to the data code.

  Further, as shown in FIG. 2B, a remote control signal indicating the distance between the infrared light emitting units 311 and 312 (hereinafter also referred to as a remote control distance signal) is a custom indicating the manufacturer of the reader unit and the remote control 30. A code, a distance data code indicating a distance between the infrared light emitting units 311 and 312, and a stop bit are included.

  The distance data code includes distance data indicating the distance between the infrared light emitting units 311 and 312 (arrangement distance between the infrared light emitting units) and inverted data obtained by inverting the bit data of the distance data. Yes. The television 10 can determine the distance between the infrared light emitting units 311 and 312 by referring to the distance data code.

(Remote control signal transmission processing)
Next, the flow of remote control signal transmission processing in the remote controller 30 will be described with reference to FIG. FIG. 3 is a flowchart showing a flow of remote control signal transmission processing in the remote control 30 according to the present embodiment.

  As shown in FIG. 3, for example, when the user accepts pressing of the “2” button (button for selecting CH2) included in the numeric keypad of the remote controller 30 (step S101), the remote controller 30 displays the state shown in FIG. A remote control channel selection signal indicating that channel 2 shown in FIG. 2 has been selected is transmitted (step S102).

  When the remote control channel selection signal is transmitted, the remote control 30 transmits a remote control distance signal shown in FIG. 2B (step S103).

  In FIG. 3, the case where the “2” button included in the remote controller 30 is pressed once has been described as an example. For example, when the “2” button is pressed long, the button is long pressed. In the meantime, the remote control channel selection signal indicating that channel 2 has been selected and the remote control distance signal may be continuously transmitted alternately.

[User position detection]
Next, detection of a user position (user distance and user angle) in the control unit 104 included in the television 10 will be described with reference to FIGS. FIG. 4 is a diagram schematically showing the remote controller 30 included in the image data captured by the camera 20. FIG. 5 is a diagram schematically illustrating the relationship between the television 10 and the remote controller 30 and the user position in the display system 1 according to the present embodiment.

  As shown in FIG. 4, the distance between the infrared light emitters 311 and 312 provided in the remote controller 30 is 3 cm. Further, as shown in FIG. 5, the distance from the center of the television 10 to the remote controller 30 (corresponding to the distance to the user) is d, and the normal direction of the LCD 115 and the direction of the remote controller 30 from the LCD 115 are horizontal. Let the angle formed along the direction be the user angle θ. Furthermore, as shown in FIG. 5, the center of the television 10 is the origin, the direction perpendicular to the LCD 115 of the television 10 is the y axis, and the direction parallel to the longitudinal direction of the LCD 115 is the x axis.

(User position detection processing)
Next, a flow of user position detection processing in the control unit 104 will be described with reference to FIG. FIG. 6 is a flowchart showing a flow of user position detection processing in the control unit 104 included in the television 10 according to the present embodiment.

  As illustrated in FIG. 6, when the remote control light receiving unit 102 receives a remote control signal from the remote control 30 (step S <b> 201), the television 10 supplies the received remote control signal to the control unit 104.

  The control unit 104 refers to the CH data code included in the remote control channel selection signal among the supplied remote control signals, and the digital broadcast receiving unit 105 receives the broadcast program transmitted via the channel indicated by the CH data code. A channel selection process for switching channels is executed (step S202).

  Further, when the remote control signal is supplied, the control unit 104 notifies the camera 20 of an imaging instruction (step S203). The camera 20 executes an imaging process according to the imaging instruction notified from the control unit 104. The camera 20 supplies the image data generated in the imaging process to the control unit 104.

  When the image data is acquired (step S204), the image recognition unit 141 of the control unit 104 detects the infrared light emitting units 311 and 312 of the remote controller 30 included in the acquired image data (step S205). The image recognition unit 141 supplies the image data detected by the infrared light emitting units 311 and 312 to the user position detection unit 142.

  The user position detection unit 142 detects the coordinates of the positions of the infrared light emitting units 311 and 312 (coordinates on the xy coordinate system shown in FIG. 5) from the supplied image data (step S206).

  Further, the user position detection unit 142 obtains the actual length of the arrangement distance between the infrared light emitting units by referring to the distance data code included in the remote control distance signal among the remote control signals supplied from the remote control light receiving unit. To do.

  The user position detector 142 calculates a distance (user distance) d between the television 10 and the user based on the detected coordinates of the infrared light emitters 311 and 312 and the arrangement distance between the infrared light emitters acquired from the remote control distance signal. Then, the viewing angle (user angle) θ of the user with respect to the television 10 is calculated (step S208).

  The user position detection unit 142 stores the calculated user distance d and user angle θ in a memory (not shown) provided in the television 10 (step S209), and also the user distance d and user angle θ already stored in the memory. And the average value of each of the user distance d and the user angle θ is calculated (step S210).

  The user position detection unit 142 determines the user distance and the user angle based on the calculated average values of the user distance d and the user angle θ, and specifies the user position (step S211).

  In the present embodiment, the user position detection process has been described by taking an example of a configuration that is executed when a remote control signal is received as illustrated in FIG. 6. A configuration that is executed by periodically repeating the processes from step S204 to S211 may be adopted.

[Black level correction]
Next, black level correction in the black control unit 113 included in the television 10 according to the present embodiment will be described with reference to FIGS.

(Black tone correction value for each condition)
First, a black gradation correction value for adjusting the black level in accordance with each condition such as the user position and the ambient illuminance will be described with reference to FIG. FIG. 7 is a graph showing black gradation correction values for each condition referred to in the black control unit 113 according to the present embodiment. In FIG. 7, the graph when the black level correction is not performed is indicated by a solid line, and the graph when the black level correction is performed is indicated by a broken line.

  FIG. 7A shows a black gradation correction value corresponding to the user angle, and the black gradation correction value is set to increase the black level gradation value as the user angle increases. Yes. Specifically, as shown in FIG. 7A, the black gradation correction value is constant at “0” when the user angle is 0 °, and the user angle is 30 ° from 0 ° to the left and right. Gradually increases from “0” to “+4”, and becomes constant at “+4” when the user angle is 30 ° or more on both the left and right sides.

  FIG. 7B shows a black gradation correction value corresponding to the user distance. The black gradation correction value is a level of the black level as the user distance increases (the distance from the LCD 115 to the user increases). It is set to increase the key value. Specifically, as shown in FIG. 7B, the black gradation correction value is “0” when the user distance is 0 (m), and the user distance is changed from 0 (m) to 3H ( m) gradually increases from “0” to “+4”, and becomes constant at “+4” when the user distance is 3H (m) or more. Note that “H” indicates the vertical length of the LCD 115 included in the television 10 (so-called screen height).

  FIG. 7C shows a black gradation correction value corresponding to the environmental illuminance, and the black gradation correction value is set so as to increase the black level gradation value as the environmental illuminance decreases. Yes. Specifically, as shown in FIG. 7C, the black gradation correction value is constant at “0” in the range where the environmental illuminance is 75 (lx) or more, and the environmental illuminance is from 75 (lx) to 30. As it decreases to (lx), it gradually increases from “0” to “+4”, and becomes constant at “+4” when the ambient illuminance is 30 (lx) or less.

  FIG. 7D shows a black gradation correction value corresponding to the ratio of the black level gradation value (black area). When the input image data includes a black area of a predetermined ratio or more, black is corrected. It is set so that the gradation value of the black level increases as the ratio of the gradation value of the level increases. Specifically, as shown in FIG. 7D, the black gradation correction value is constant at “0” when the black area is 75% or less, and the black area increases from 75% to 85%. Gradually increases from “0” to “+4” and becomes constant at “+4” in the range of 85% or more.

  FIG. 7E shows a black gradation correction value corresponding to the average luminance level, and is set so that the gradation value of the black level increases as the average luminance level value of the input image data decreases. ing. Specifically, as shown in FIG. 7E, the average luminance level is “0” in the range of 30% or more, and “0” as the average luminance level decreases from 30% to 0%. To "+4".

  In the present embodiment, a black gradation correction value for each condition shown in FIG. 7 is stored in advance as a black gradation correction value table in a storage unit (not shown) of the television 10 as an example. Although described below, the present invention is not limited to this, and a configuration that is calculated in the black control unit 113 every time the black level gradation value adjustment is executed may be employed.

  In the following description, the black gradation correction value table representing the black gradation correction value with respect to the user angle shown in FIG. 7A is referred to as the black gradation correction value table a, and the black gradation correction value with respect to the user distance shown in FIG. The black gradation correction value table representing the black gradation correction value table b, and the black gradation correction value table representing the black gradation correction value for the ambient illuminance shown in FIG. A black gradation correction value table representing black gradation correction values with respect to the ratio of the black area shown in FIG. 5 is a black gradation correction value table d, and a black gradation correction value representing black gradation correction values with respect to the average luminance level shown in FIG. The table is referred to as a black gradation correction value table e.

  The black gradation correction control unit 131 of the black control unit 113 is based on the user position information supplied from the control unit 104, the ambient illuminance, and the black area information and average brightness level supplied from the detection unit 112. With reference to the correction value tables a to e, a black gradation correction value (also referred to as a black gradation correction processing value) for finally correcting the black gradation of the input image data is generated.

  The black gradation correction control unit 131 supplies the generated black gradation correction processing value to the black level correction instruction unit 132, and the black level correction instruction unit 132 supplies the supplied black gradation correction processing value to the video processing unit 111. To supply.

  For example, when the black gradation correction control unit 131 includes black areas in the input image data at a predetermined ratio (for example, 75%) or more and the environmental illuminance is equal to or less than the predetermined illuminance (for example, 75 lx), A black gradation correction processing value is generated with reference to the black gradation correction value table a, the black gradation correction value table c, and the black gradation correction value table d.

  The video processing unit 111 corrects the gradation value of the black gradation included in the input image data according to the black gradation correction processing value supplied from the black level correction instruction unit 132. In addition, the video processing unit 111 supplies input image data in which the correction value of the black gradation is corrected to the LCD controller 114, and the LCD controller 114 drives the LCD 115 so that the supplied input image data is displayed.

  As a result, the television 10 can make the black color displayed on the LCD 115 more uniform according to the angle at which the user views the LCD 115. Black color with reduced unevenness can be presented. In addition, since the television 10 has a bright ambient illuminance and luminance unevenness and color unevenness are not conspicuous, the gradation value of the black gradation is not corrected. Can be prevented from being consumed.

  When any two or more of the black gradation correction value tables a to e are referred to, the maximum value of the black gradation correction processing value is a value obtained by adding the black gradation correction value of each black gradation correction value table. Alternatively, when the value obtained by adding the black gradation correction values in each black gradation correction value table exceeds “+4”, “+4” may be set as the maximum value.

  Note that the value of the black gradation correction value for each condition is not particularly limited to the values shown in FIG. 7, and for example, a configuration that changes depending on the genre of input image data (for example, movies, sports, etc.) is adopted. May be. Thereby, the television 10 can perform the optimum black gradation correction according to the genre.

(Interlocking black tone correction and backlight control)
Next, the background is set so as to cancel the luminance increased by the black gradation of the input image data corrected (increased) by the video processing unit 111 in accordance with the black gradation correction processing value instructed by the black level correction instruction unit 132. A configuration in which the apparent luminance is kept substantially constant by reducing the luminance of the light will be described with reference to FIG. FIG. 8 is a graph showing the luminance value with respect to the input gradation.

  FIG. 8A shows the black gradation correction processing value for the input gradation, which is instructed by the black level correction instruction unit 132, and FIG. 8B shows the backlight that is lowered according to the black gradation correction processing value. The luminance of the backlight with respect to the input gradation is shown. FIG. 8C shows the brightness of the LCD 115 with respect to the input gradation when γ = 1.0, and FIG. 8D shows the brightness of the LCD 115 with respect to the input gradation when γ = 2.2. (E) shows the luminance of the LCD 115 with respect to the input gradation when the backlight luminance is controlled. In FIG. 8, the graph when the black level is not corrected is indicated by a solid line, and the graph when the black level is corrected is indicated by a broken line.

  The video processing unit 111 adjusts the black level of the input image data based on the black gradation correction processing value shown in FIG. 8A, thereby providing an input image having a luminance with respect to the input gradation as shown in FIG. Generate data. Further, the video processing unit 111 performs gamma correction so that the gamma characteristic of the input image data becomes γ = 1 to γ = 2.2, so that the luminance with respect to the input gradation as shown in FIG. Having input image data.

  The video processing unit 111 supplies input image data having luminance characteristics with respect to the input gradation as shown in FIG. 8D to the LCD controller 114, and the LCD controller 114 displays the supplied input image data so as to display the supplied input image data. Drive.

  At this time, as shown in FIG. 8B, the backlight control unit 133 reduces the light emission rate of the backlight 116 according to the black gradation correction processing value shown in FIG. Reduce brightness.

  As a result, the backlight control unit 133 cancels the luminance increased by the increased black gradation value of the input image data by decreasing the luminance of the backlight 116, as shown in FIG. Furthermore, the apparent luminance can be made substantially the same.

  When black display is performed by correcting the black level as described above and controlling the luminance of the backlight 116 as compared with the black display normally performed shown in FIG. As shown in FIG. 4, it is possible to reduce the luminance unevenness and the color unevenness of black and to keep the apparent luminance at substantially the same luminance. Thus, with the above-described configuration, the television 10 can reduce the black luminance unevenness and color unevenness represented by the input image data, and can present it to the user with substantially the same apparent luminance.

  In the present embodiment, the case where the camera 20 is connected to the television 10 via the USB cable has been described as an example. However, the present embodiment is not limited to this.

  For example, as shown in FIG. 10, a configuration in which the camera 20 ′ is built in the television 10 may be employed. FIG. 10 is a diagram showing an example of an outline of the display system 1 ′ according to the present embodiment.

<Modification>
Although the case where the remote control device is realized by the remote controller 30 has been described as an example, the present embodiment is not limited to this, and for example, a configuration realized by a smartphone may be adopted.

  A case where the remote control device is realized by a smartphone will be described with reference to FIGS. 11 to 13. For convenience of explanation, components having functions similar to those of the components according to the present embodiment are denoted by the same reference numerals, and description thereof is omitted.

  FIG. 11 is a diagram schematically illustrating a smartphone (remote control device) 40 included in image data captured by the camera 20 according to the present modification. FIG. 12 is a diagram illustrating an example of an outline of the display system 2 according to a modification of the present embodiment.

  As shown in FIG. 12, the display system 2 according to this modification includes a television 10, a camera 20, a smartphone 40, and a wireless router 45.

  The smartphone 40 includes a wireless signal transmission unit 401, LEDs (light emitting units) 411 and 412, and an LED light emission control unit 413. In addition, the television 10 further includes a wireless signal receiving unit (acquisition means) 118.

  The wireless signal transmission unit 401 transmits a wireless signal to the television 10 via the wireless router 45. Note that the transmitted radio signal is the same signal as the remote control signal shown in FIG. The television 10 receives the wireless signal transmitted from the wireless signal transmission unit 401 via the wireless router 45 at the wireless signal reception unit 118.

  The LED light emission control unit 413 causes the LEDs 411 and 412 to emit light when a wireless signal is transmitted from the wireless signal transmission unit 401. In addition, although the case where the smartphone 40 includes two LEDs will be described as an example, the present modification is not limited to this, and for example, a configuration including three or more LEDs is adopted. Also good.

(User position detection)
As shown in FIG. 11, the distance between the LEDs 411 and 412 provided in the smartphone 40 is 2 cm.

  At this time, the radio signal transmission unit 401 transmits a radio signal (radio distance signal) including data indicating that the distance between the LEDs 411 and 412 is 2 cm. In the wireless distance signal, similar to the remote control distance signal shown in FIG. 2, the distance data code included in the transmitted wireless signal includes distance data indicating that the distance between the LEDs 411 and 412 is 2 cm, and Inverted data obtained by inverting bit data of distance data is included.

  Next, the flow of wireless signal transmission processing in the smartphone 40 will be described with reference to FIG. FIG. 13 is a flowchart illustrating a flow of wireless signal transmission processing in the smartphone 40 according to the modification of the present embodiment.

  As illustrated in FIG. 13, when the user presses the button for selecting channel 2 (step S301), the LED light emission control unit 413 included in the smartphone 40 emits the LEDs 411 and 412 (step S302).

  When the LEDs 411 and 412 are caused to emit light, the smartphone 40 transmits a radio channel selection signal indicating that channel 2 has been selected, similar to the remote control channel selection signal illustrated in FIG. 2A (step S303).

  When the wireless channel selection signal is transmitted, the smartphone 40 transmits a wireless distance signal similar to the remote control distance signal shown in FIG. 2B (step S304).

  In addition, reception of the pressing of the button which selects the channel 2 by the user in the smart phone 40 is detected, for example, by detecting that the user touches the “2” button displayed on the touch panel (not shown) provided in the smart phone 40. It only needs to be accepted.

  In FIG. 13, the case where the “2” button included in the smartphone 40 is pressed once has been described as an example. For example, when the “2” button is pressed long, the smartphone 40 While the button is pressed, it is only necessary to continuously transmit a radio channel selection signal indicating that channel 2 has been selected and a radio distance signal.

  Thus, even when the remote control device is the smartphone 40, the black level of the input image data can be adjusted as in the case of the remote control 30.

[Program, storage medium]
Each block of the television 10 may be realized in hardware by a logic circuit formed on an integrated circuit (IC chip), or may be realized in software using a CPU (Central Processing Unit).

  In the latter case, the television 10 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, the program, and various data. A storage device (recording medium) such as a memory for storing the. An object of the present invention is to provide a recording medium on which a program code (execution format program, intermediate code program, source program) of a control program of the television 10 which is software for realizing the above-described functions is recorded so as to be readable by a computer. This can also be achieved by reading the program code recorded in the recording medium and executing it by the computer (or CPU or MPU).

  Examples of the recording medium include tapes such as magnetic tapes and cassette tapes, magnetic disks such as floppy (registered trademark) disks / hard disks, and disks including optical disks such as CD-ROM / MO / MD / DVD / CD-R. IC cards (including memory cards) / optical cards, semiconductor memories such as mask ROM / EPROM / EEPROM (registered trademark) / flash ROM, PLD (Programmable logic device) and FPGA (Field Programmable Gate) Logic circuits such as (Array) can be used.

  The program code may be supplied to the television 10 via a communication network. The communication network is not particularly limited as long as it can transmit the program code. For example, the Internet, intranet, extranet, LAN, ISDN, VAN, CATV communication network, virtual private network, telephone line network, mobile communication network, satellite communication network, etc. can be used. 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 with wired lines such as IEEE 1394, USB, 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), IEEE 8021 wireless, HDR (High Data Rate, NFC (Near Field Communication), DLNA (Digital Living Network Alliance), mobile phone network, satellite line, terrestrial digital network, etc. can also be used.

  In addition, this invention is not limited to embodiment mentioned above, A various change is possible in the range shown to the claim.

  The display device according to the present invention can be suitably applied to an LED driver device that drives an LED. Further, it can be suitably applied to lighting devices, display devices, television receivers, smartphones, mobile phones, digital cameras, electronic blackboards, and the like.

1, 1 ', 2 Display system 10 Television (display device)
20, 20 'Camera 30 Remote control (remote control device)
40 Smartphone (remote control device)
45 Wireless router 101 USB interface 102 Remote control light receiving unit (acquisition means)
DESCRIPTION OF SYMBOLS 103 Illuminance sensor 104 Control part 105 Digital broadcast receiving part 106 HDMI interface 107 Input switching part 108 Frame memory 109 Histogram analysis part 110 Image quality calculation processing part 111 Video processing part 112 Detection part 113 Black control part 114 LCD controller 115 LCD (display)
116 Backlight 118 Radio signal receiver (acquisition means)
121 Black Area Detection Unit 122 APL Detection Unit 131 Black Tone Correction Control Unit (Tone Value Correction Unit)
132 Black level correction instruction section (tone value correction means)
133 Backlight control unit (backlight control means)
141 Image recognition unit (identification means)
142 User position detection unit (angle detection means, distance calculation means)
143 Environmental illuminance determination unit (illuminance detection means)
201 Lens 202 CMOS Image Sensor 203 Encoder 204 CPU
205 USB interface 301 Remote control signal transmission unit 311, 312 Infrared light emitting unit (light emitting unit)
401 Wireless signal transmission unit 411, 412 LED (light emitting unit)
413 LED light emission control unit

Claims (9)

A display device operated by a remote control device,
Illuminance detection means for detecting ambient illuminance;
An angle detecting means for detecting an angle formed along a horizontal direction between a normal direction of the display and a direction of the remote control device based on the display;
When the input image data includes a gradation value equal to or less than a predetermined gradation and the ambient illuminance is equal to or less than the predetermined illuminance, the gradation value equal to or less than the predetermined gradation is Gradation value correction means for increasing according to the angle;
Backlight control means for reducing the brightness of the backlight so as to cancel out the increase in the gradation value by the gradation value correction means,
A display device characterized by that. The increase in the gradation value by the gradation value correcting means is larger as the angle is larger.
The display device according to claim 1. The increase in the gradation value by the gradation value correcting means is larger as the ambient illuminance is lower.
The display device according to claim 1 or 2. The remote control device includes a plurality of light emitting units,
The display device
Obtaining means for obtaining information indicating the distance between the plurality of light emitting units;
Identification means for identifying the plurality of light emitting units from image data obtained by imaging the remote control device;
The distance from the display to the remote control device is calculated based on the information indicating the distance between the plurality of light emitting units acquired by the acquiring unit and the plurality of light emitting units identified by the identifying unit. A distance calculating means for
The increase in the gradation value by the gradation value correcting means is larger as the distance from the display to the remote control device is larger.
The display device according to claim 1, wherein the display device is a display device. The increase in the gradation value by the gradation value correcting means is larger as the average luminance level is smaller.
The display device according to claim 1, wherein the display device is a display device. A method for correcting a gradation value of a display device operated by a remote control device,
Illuminance detection step for detecting ambient illuminance;
An angle detection step for detecting an angle formed along a horizontal direction between a normal direction of the display and a direction of a remote control device based on the display;
When the input image data includes a gradation value equal to or less than a predetermined gradation and the ambient illuminance is equal to or less than the predetermined illuminance, the gradation value equal to or less than the predetermined gradation is A gradation value correcting step for increasing according to the angle;
A backlight control step for reducing the luminance of the backlight so as to cancel out the increase in the gradation value in the gradation value correction step.
A gradation value correction method characterized by the above. Each unit of the display device according to any one of claims 1 to 5 is provided.
A television receiver characterized by that.   A program for operating a computer as the display device according to any one of claims 1 to 5, wherein the computer functions as each unit of the display device. A computer-readable recording medium on which the program according to claim 8 is recorded.