WO2012124081A1

WO2012124081A1 - Display device

Info

Publication number: WO2012124081A1
Application number: PCT/JP2011/056273
Authority: WO
Inventors: 勇釼持
Original assignee: Ｎｅｃディスプレイソリューションズ株式会社
Priority date: 2011-03-16
Filing date: 2011-03-16
Publication date: 2012-09-20

Abstract

Provided is a display device which can be set up in a state in which only the display surface of the display device is exposed, and which is provided with a communication means that enables the display device to be set up etc. by remote control. This display device (10) is provided with: a liquid crystal panel (2) which displays images; a backlight (3) which provides illumination from the rear, on the opposite side of the display surface of the liquid crystal panel; a visible light receiving unit (4) which transmits light received from the display surface side of the liquid crystal panel through the liquid crystal panel and the backlight, and receives light emitted from the surface of the backlight on the opposite side to where the liquid crystal panel is positioned, and outputs a signal corresponding to the intensity of the received light; and a communication unit which communicates with the outside using visible light on the basis of the signal outputted from the visible light receiving unit.

Description

Display device

The present invention relates to a display device that communicates with the outside using a backlight monitoring sensor in a display device using a liquid crystal panel and a backlight.

Conventionally, there has been known an information device that uses a visible light source of a backlight and has a backlight function and a communication function with an external device. The information device includes a plate-shaped light guide plate including an incident surface on which light is incident, a light emission surface substantially orthogonal to the incident surface, and a bottom surface facing the light emission surface, and an incident surface of the light guide plate. An LED serving as a light source disposed in close proximity and a photodiode serving as a light receiving element disposed in close proximity to the incident surface of the light guide plate, the bottom surface of the light guide plate being substantially parallel to the incident surface; Grooves cut in the direction of the exit surface are arranged at predetermined intervals. With this configuration, an optical communication device having a backlight function and a visible light communication function can be realized by using a light source and a light receiving element that are arranged in the vicinity of the light guide plate (see, for example, Patent Document 1).

JP 2006-319408 A

Incidentally, in a display device using liquid crystal, in order to widen the display area, the communication terminal is generally not provided on the front surface of the display device but on the back surface. In this case, in the installation method in which the display device is embedded in a wall or the like that cannot be reached, the communication terminal cannot be used in the installed state. In addition, in some conventional displays, the display device is set by a remote controller using light communication using light, but the light receiving unit for communication must be exposed on the front of the display device. In the case of embedding in a wall or the like, there is a problem that it cannot be installed so that only the display surface is exposed.

The present invention has been made in view of such circumstances, and provides communication means that can be installed in a state where only the display surface of the display device is exposed and can set the display device by remote control. An object is to provide a display device provided.

The present invention provides a liquid crystal panel that displays an image, a backlight that illuminates from a back surface opposite to the display surface of the liquid crystal panel, and light incident from the display surface side of the liquid crystal panel. A light receiving unit that transmits light, receives light emitted from the opposite surface of the backlight on which the liquid crystal panel is disposed, and outputs a signal corresponding to the intensity of the received light; and the light receiving unit And a communication unit that performs communication using visible light with the outside based on a signal output from the unit.

The present invention is characterized in that the light receiving unit is an optical sensor provided for monitoring the intensity of light emitted from the backlight.

The present invention is characterized in that when the communication unit performs communication, the liquid crystal panel is in a white display state.

The present invention is characterized in that the backlight is turned off when the communication unit performs communication.

According to the present invention, it is possible to install the display device in a state in which only the display surface of the display device is exposed, and to obtain an effect that the display device can be set by remote control.

It is a block diagram which shows the structure of one Embodiment of this invention. It is a flowchart which shows operation | movement of the apparatus shown in FIG. It is explanatory drawing which shows an example of the mark displayed on the screen center of the liquid crystal panel 2 shown in FIG.

Hereinafter, a display device according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing the configuration of the embodiment. In this figure, reference numeral 1 denotes a visible light communication transmitter that performs wireless communication using visible light, and emits modulated light based on a control signal 20. Reference numeral 2 denotes a liquid crystal panel for displaying an image. Reference numeral 3 denotes a backlight provided on the back surface of the liquid crystal panel 2, which is composed of a surface light source having at least the same shape and area as the display surface of the liquid crystal panel 2. However, the light emitting surface of the backlight 3 and the surface opposite to the light emitting surface are made of a material that transmits visible light, and light incident from the light emitting surface side is transmitted through the backlight 3 and is opposite to the light emitting surface. The light is emitted from the side surface. Reference numeral 4 denotes a visible light receiving unit that receives light emitted from the backlight 3 in order to keep the intensity of light emitted from the backlight 3 constant, converts the intensity of the received light into a voltage, and outputs the voltage. Consists of sensors. The visible light receiving unit 4 is also used to receive the visible light control signal 21 for performing wireless communication emitted from the visible light communication transmitting unit 1. Reference numeral 5 denotes a video processing circuit that performs processing for converting a video signal 22 input from the outside into a signal that can be displayed on the liquid crystal panel 2 and outputs an input video signal 30 to the liquid crystal panel 2.

Reference numeral 6 denotes a low-pass filter (hereinafter referred to as LPF) that removes noise from the visible light receiving unit output voltage 35 output from the visible light receiving unit 4. Reference numeral 7 denotes an AD converter (input of the visible light receiving unit output voltage 36 after noise removal output from the LPF 6, performs AD (analog-digital) conversion, and outputs a digital signal 33 indicating the brightness of the backlight. Hereinafter referred to as ADC). Reference numeral 8 is a CPU that controls the overall processing operation of the display device 10. Reference numeral 9 denotes a timer that keeps time, and receives the visible light receiving unit output voltage 35 output from the visible light receiving unit 4 and outputs the time 34 when visible light is received. The CPU 8 outputs a video processing circuit control value 31 to the video processing circuit 5 to control the processing operation of the video processing circuit 5 and inputs a signal 33 indicating the brightness of the backlight output from the ADC 7. The intensity of light emitted from the backlight 3 is controlled by outputting a backlight control signal 32 to the backlight 3 based on the signal 33 indicating the brightness of the backlight.

Next, the processing operation of the display device 10 shown in FIG. 1 will be described with reference to FIG. FIG. 2 is a flowchart showing the processing operation of the display device 10 shown in FIG. First, when a visible light signal is transmitted from the display device 10 visible light communication transmitter 1 and setting of the display device 10 is performed, a personal computer or the like connected to the display device 10 is operated, and all of the liquid crystal panel 2 is operated. The video signal 22 input to the video processing circuit 5 is output so that the screen is white. In response to this, the video processing circuit 5 inputs a video signal 22 that is white on the entire screen, processes the input video signal, generates an input video signal, and outputs the input video signal to the liquid crystal panel 2. As a result, the liquid crystal panel 2 displays the entire screen in white (step S101). Next, based on the control signal 20, the visible light communication transmitter 1 irradiates the display surface of the liquid crystal panel 2 with visible light that is the visible light control signal 21 (step S102). The visible light that is the visible light control signal 21 passes through the liquid crystal panel 2 and the backlight 3 and reaches the visible light receiving unit 4. At this time, since the liquid crystal panel 2 is in a white display state, the light transmittance of the liquid crystal panel 2 is the maximum value, and the visible light of the visible light control signal 21 is easily transmitted.

The visible light receiving unit 4 converts the light received by photoelectric conversion into a voltage and outputs it as a signal of the visible light receiving unit output voltage 35. This signal is output to the LPF 6 and the timer 9. The LPF 6 receives a signal of the visible light receiving unit output voltage 35 output from the visible light receiving unit 4 and removes a high frequency component of the signal of the visible light receiving unit output voltage 35 to remove noise, thereby removing noise. The signal is output to the ADC 7 as a signal of the subsequent visible light receiving unit output voltage 36. The ADC 7 receives the signal of the visible light receiving unit output voltage 36 after the noise removal, converts it to a digital value, and converts the brightness of the backlight 33 (the brightness of the backlight on which the visible light of the visible light control signal 21 is superimposed). To the CPU 8 as a signal. On the other hand, the timer 9 inputs the signal of the visible light receiving unit output voltage 35 output from the visible light receiving unit 4 and outputs the signal of the time 34 when the visible light is received to the CPU 8.

The CPU 8 detects the intensity of the received light within a predetermined time from the signal of the time 34 when the visible light output from the timer 9 is received and the signal of the brightness 33 of the backlight output from the ADC 7 (step S103), it is determined whether or not a signal indicating the start of communication is transmitted from the visible light communication transmitter 1 based on whether or not the detected light intensity pattern is a predetermined intensity pattern. As a result of this determination, when it is determined that a signal indicating the start of communication is transmitted from the visible light communication transmitter 1, the CPU 8 displays the center of the screen of the liquid crystal panel 2 as shown in FIG. Is displayed (step S104). At this time, the CPU 8 outputs to the video processing circuit 5 the video processing circuit control signal 31 including the image data with the mark shown in FIG. When the video processing circuit control signal 31 is output from the CPU 8, the video processing circuit 5 stops the display based on the input video signal 22 and performs screen display based on the video processing circuit control signal 31 output from the CPU 8. In addition, the input video signal 30 is output to the liquid crystal panel 2. As a result, the mark shown in FIG. 3 is displayed on the liquid crystal panel 2. Then, the CPU 8 changes the liquid crystal panel to a single display after a predetermined time has elapsed (step S105).

Next, the CPU 8 outputs a backlight control signal 32 for turning off the backlight to the backlight 3. In response to this, the backlight 3 is turned off (step S106). Subsequently, a visible light control signal 21 using visible light is transmitted from the visible light communication transmitter 1 to perform serial communication (step S107). At this time, adjustment is performed so that visible light for performing communication emitted from the visible light communication transmitter 1 is applied to the center of the mark displayed in the liquid crystal panel 2 (inside the broken-line rectangle shown in FIG. 3). The dotted rectangle shown in FIG. 3 coincides with the position where the visible light receiving unit 4 is arranged, and the inside of the rectangle is displayed in white, so that the light transmitted through the liquid crystal panel 2 is transmitted. The rate is also high, and the backlight 3 is turned off. Therefore, the visible light control signal 21 can be efficiently guided to the visible light receiving unit 4 by irradiating visible light for communication within the rectangle. The visible light control signal 21 for communication is received by the visible light receiving unit 4 and converted into a voltage signal. After noise removal, the signal is digitally converted and input to the CPU 8. The CPU 8 specifies information indicated by the visible light control signal 21 based on the signal output from the ADC 7 and executes processing such as setting based on the specified information.

Next, the CPU 8 determines whether there is no communication for 1 minute or more based on whether there is no signal input for communication for 1 minute or more (step S108). If communication is continued as a result of this determination, the process returns to step S107, and communication using visible light is continued. On the other hand, when there is no communication for 1 minute or more and the communication is completed, the CPU 8 outputs a backlight control signal 32 for turning on the backlight to the backlight 3. In response to this, the backlight 3 is turned on. Then, the CPU 8 displays the result of the setting process performed by communication on the screen of the liquid crystal panel 2 (step S109), cancels the communication state, and returns to the normal display (step S110).

As described above, in a display device including a liquid crystal panel that displays an image and a backlight that illuminates from the back side opposite to the display surface of the liquid crystal panel, light incident from the display surface side of the liquid crystal panel is liquid crystal A light receiving unit that transmits light through the panel and backlight, receives light emitted from the opposite surface where the liquid crystal panel of the backlight is disposed, and outputs a signal according to the intensity of the received light is provided. Since it has a communication unit that communicates with the outside using visible light based on the signal output from the light receiving unit, it can be installed with only the display surface of the display device exposed, and the display device can be operated remotely. Can be set.

1 is recorded on a computer-readable recording medium, and the program recorded on the recording medium is read into a computer system and executed to perform wireless communication processing. May be. Here, the “computer system” includes an OS and hardware such as peripheral devices. The “computer-readable recording medium” refers to a storage device such as a flexible medium, a magneto-optical disk, a portable medium such as a ROM or a CD-ROM, and a hard disk incorporated in a computer system. Further, the “computer-readable recording medium” refers to a volatile memory (RAM) in a computer system that becomes a server or a client when a program is transmitted via a network such as the Internet or a communication line such as a telephone line. In addition, those holding programs for a certain period of time are also included.

The program may be transmitted from a computer system storing the program in a storage device or the like to another computer system via a transmission medium or by a transmission wave in the transmission medium. Here, the “transmission medium” for transmitting the program refers to a medium having a function of transmitting information, such as a network (communication network) such as the Internet or a communication line (communication line) such as a telephone line. The program may be for realizing a part of the functions described above. Furthermore, what can implement | achieve the function mentioned above in combination with the program already recorded on the computer system, what is called a difference file (difference program) may be sufficient.

In a display device using a liquid crystal panel and a backlight, it can be applied to applications where wireless communication is indispensable.

DESCRIPTION OF SYMBOLS 1 ... Visible light communication transmission part, 2 ... Liquid crystal panel, 3 ... Back light, 4 ... Visible light light-receiving part, 5 ... Image processing circuit, 6 ... LPF, 7 ...・ ADC, 8 ... CPU, 9 ... Timer

Claims

A liquid crystal panel for displaying images;
A backlight for illuminating from the back side opposite to the display surface of the liquid crystal panel;
Light incident from the display surface side of the liquid crystal panel passes through the liquid crystal panel and the backlight, receives light emitted from the opposite surface of the backlight where the liquid crystal panel is disposed, and receives light. A light receiving unit that outputs a signal according to the intensity of the light,
And a communication unit that performs communication using visible light with the outside based on a signal output from the light receiving unit.
The display device according to claim 1, wherein the light receiving unit is an optical sensor provided to monitor the intensity of light emitted from the backlight.
3. The display device according to claim 1, wherein when the communication unit performs communication, the liquid crystal panel is in a white display state.
4. The display device according to claim 1, wherein the backlight is turned off when the communication unit performs communication.