JPH08126028A - Data transmission system - Google Patents

Abstract

PURPOSE: To send data between a video display device and other device without interconnecting the devices by a cable or without the providing a special transmitter by providing a video display device having a means allocating a color to data to be sent corresponding to its content and a means displaying a graphic having the allocated color to the system. CONSTITUTION: A video display device 10 has a display section 11 comprising a CRT or a liquid crystal display device using R, G, B color signals to display a color image. A data processing unit 15 processes data fed from the video display device 10 and gives a feedback signal to the video display device 10. Internal information of th video display device 10 is fed to an encoder 12 in the inside of the device, in which the information is converted into an OSD(on screen data) signal and fed to an OSD display section 13, in which the signal is converted into a video signal and the signal is displayed on the screen. The video image is received by an OSD light receiving section 16 of the data processing unit 15. The data processing unit 15 processes the data and an infrared ray light emitting section 18 gives a feedback signal to an infrared ray receiving section 14.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a system for executing data transmission between a video display device having a display screen such as a CRT or a liquid crystal display and another device.

[0002]

2. Description of the Related Art Conventionally, when the internal information of a video display device is sent to another device, two devices are conventionally connected by a cable as shown in FIG. 3 (a) or as shown in FIG. 3 (b). Signals are transmitted wirelessly by infrared rays or ultrasonic waves.

[0003]

However, when connecting the devices with a cable, there is a space limitation, and
There is a problem that complicated connection work occurs. Further, when transmitting a signal wirelessly, it is necessary to provide a dedicated transmission circuit, which causes a problem in cost.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to enable data transmission between a video display device and another device without connecting the devices with a cable or providing a special transmitter. The purpose is to

The above object of the present invention comprises a video display device having means for assigning a color to data to be transmitted in correspondence with the content of the data, and means for displaying a graphic having the assigned color. This is achieved by the data transmission system according to claim 1.

The above object of the present invention further has a color assigned corresponding to the content of data to be transmitted,
3. The light receiving device according to claim 2, further comprising a light receiving device having means for optically reading a graphic displayed on a screen and means for analyzing the color of the graphic read to reproduce the data to be transmitted. Achieved by a data transmission system.

The above object of the present invention is further directed to a video display device having means for assigning a color to data to be transmitted corresponding to the contents thereof, and means for displaying a graphic having the assigned color, and the above display. 4. The data transmission system according to claim 3, further comprising: a light receiving device having means for optically reading the read graphic and means for analyzing the color of the read graphic to reproduce the data to be transmitted. To be achieved.

The object of the present invention is also to provide a timing circuit in which the light receiving device operates in synchronization with the video display device, and a DC level of light received in synchronization with a timing signal output from the timing circuit. Means for detecting
And a means for comparing the detected DC level with a predetermined value.

The object of the present invention is further to obtain an average of the light receiving level when the light receiving device is displaying a graphic from the light receiving level when the video display is displaying a graphic. A data transmission system according to claim 5, characterized in that it comprises means for subtracting a value.

The object of the present invention is further characterized in that each bit of the 3-bit data is associated with an R, G, B color signal, respectively. Achieved by a data transmission system.

[0011]

In the system according to the first aspect, the data to be displayed is color-displayed on the CRT or the liquid crystal display, preferably in the shape of a quadrangle.

In the system according to the second aspect, the received light is separated into R, G and B colors, and the data is reproduced from the detection result.

In the system according to the third aspect, the image displayed on the image display device is received by the light receiving device, its color is analyzed, and the data is reproduced.

In the system according to the fourth aspect, the level of the received light is compared with a predetermined value, and it is discriminated whether the light is the light of the graphic displayed on the video display device or the external light.

In the system described in claim light 5, the level of external light is subtracted from the received light level to minimize the influence of external light.

In the system according to the sixth aspect, each bit of the 3-bit data is made to correspond to R, G, and B to enable transmission of 3-bit parallel data.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the data transmission system of the present invention will be described below with reference to the drawings.

In FIG. 1, reference numeral 10 is a video display device having a display unit 11 composed of a CRT or a liquid crystal display capable of displaying a color image using R, G, B color signals, and 15 is a display device. The data processing device processes data sent from the video display device 10 and supplies a feedback signal to the video display device 10.

The internal information of the video display device 10 is sent to an encoder 12 inside the device and converted into an OSD (on-screen data) signal. At this time, if the internal information is an analog signal, the A / D arranged in the encoder
It is converted into a digital signal by a converter and then converted into an OSD signal. The OSD signal is sent to the OSD display control unit 13, converted into a video signal and displayed on the screen.

The OSD signal is a signal composed of a bit string divided into 3 bits so as to correspond to R, G and B.

For example, the signal "011" has R = 0 and G =
1, B = 1, which corresponds to cyan. Further, as shown in FIG. 4, the signal “100110101111” is
It is separated from (100), (110), (101), and (111), and is represented as (red) (yellow) (magenta) (white).

The above OSD signal is displayed on the display unit 11 as a rectangular figure. This is because the memory capacity for storing the OSD signal in the video display device 10 is small and the light emission period can be lengthened. If there is enough memory capacity, it is possible to divide the quadrangle into upper and lower parts, or divide it into four parts to increase the amount of transmission data.

As shown in FIG. 6, in the display unit 11,
If 24 characters are displayed in the horizontal direction and 12 characters are displayed in the vertical direction, 24 × 12 × 3 × 60 = 51840 bits can be transmitted per second.

In this case, as shown in FIG. 7, since one vertical scanning period includes 525/2 = 262.5 scanning lines, each quadrangle is 262.5 / 12, that is, about 2.
It will be formed from 1.8 scan lines. Incidentally, FIG.
As shown in (4), among the displayed squares, those on the top line are all black so as to form a blanking period that distinguishes the next transmission from the previous transmission.

The square image displayed on the display unit 11 is
OSD light receiver 16 of data processor 15 as OSD light
Is received by. FIG. 2 shows details of the OSD light receiving section.
The OSD light is converted into parallel light by the condenser lens 20, and an R, G, and
The light of each color of B is separated. The separated R, G, B lights are detected by a photodetector 22 composed of an element such as a CCD.
Are converted into electric signals respectively. Each photodetector is
When it detects light, it outputs "1". , For example (red)
The light of (yellow) (magenta) (white) emits light.
From the photodetector 22, (R
The signals GB) = (100) (110) (101) (111) are sent to the outside light identification circuit 24.

As shown in FIG. 9, the outside light discriminating circuit 24 shapes the signal output from the photodetector 22 into a square wave through a limiter circuit, and then operates in synchronization with the image display device 10 with a timing circuit 23. It is determined whether or not the received light is the OSD light,
Identify whether it is background light (external light).

Further, as shown in FIG. 10, it has a function of changing the threshold level of the limiter circuit in accordance with the average value of the DC level (that is, the level of external light) detected during the blanking period.

For example, it is assumed that the waveform is normally shaped by the threshold level E2 of the limiter circuit when the direct current level E1 of the external light is as shown in FIG. 10 (a).
Now, assuming that the DC level of outside light changes from E1 to E3 as shown in FIG. 10B, the shaped waveform will be out of synchronization with the timing signal unless the threshold level of the limiter circuit remains E2. I will end up. Therefore, the threshold level is changed from E2 to E4 in accordance with the external light direct current level.
Normal waveform shaping can be performed by changing to.

Here, the image display device 10 is a television receiver, the data processing device 15 is an automatic adjusting device for the television receiver, and the television receiver outputs the OSG signal as an output voltage of its AGC. Consider the case where the value of is transmitted to the automatic adjuster. AGC voltage is 0V to 9V
Shall vary within the range of. 0V to (000000)
When transmitting as a 6-bit signal in which 9V is (111111), if the AGC voltage is 5.2V, this 5.2V becomes (100101), and the OS
The D signal is a two-color signal of (red) (magenta).

The automatic adjuster 15 obtains signals (100) and (101) from (red) (magenta) and further decodes them by the decoder 17 to obtain a signal (100101). Therefore, the value of the transmitted AGC voltage is 5.203 (= 9 ÷
It is determined to be 64 × 37) V. Assuming that the normal value of the AGC voltage is 4.5V, the automatic adjuster 15
A feedback signal is sent from the infrared light emitting portion 18 to the infrared light receiving portion 14 of the television receiver 10 to instruct to lower the AGC voltage.

In this way, bidirectional communication is performed between the television receiver 10 and the automatic adjuster 15, and the television receiver can be automatically adjusted.

In the automatic AGC adjustment described above, of the 288 characters that can be simultaneously displayed on the display unit 11,
Although two characters are used, various controls can be performed by using the other 266 characters.

The same RGB is used for the video processing device 10.
By providing the selection function and the infrared emission function, it is possible to perform bidirectional communication with various devices.

When the image processing device 10 is a television receiver, it is preferable that the data processing device 15 is provided with a lens for focusing on the CRT screen to reduce the influence of external light.

As described above, the system of this embodiment is a kind of optical communication system using the three colors of R, G, and B, and can transmit three times as much information as in monochromatic optical communication. it can. Therefore, automatic adjustment of the television receiver and various displays can be efficiently performed. In addition, two-way communication between various systems and a television receiver, for example, a remote controller of a television can be used to make a call, adjust an air conditioner, and operate a stereo.

[0036]

In the system according to the first aspect, the contents of the data to be displayed are displayed on the CRT or the liquid crystal display.
It can be represented by a graphic of a color corresponding to the content.

In the system according to the second aspect and the third aspect, the color of the received light is analyzed to reproduce the transmission data, so that the parallel data can be transmitted and received.

In the system according to the fourth aspect, since the level of the received light is compared with a predetermined value, it is possible to discriminate whether it is the light of the displayed graphic or the external light.

In the system according to the fifth aspect, the average value of the level of external light can be subtracted from the light receiving level to minimize the influence of external light and improve the reliability of data transmission.

In the system according to the sixth aspect, each bit of the 3-bit data is made to correspond to R, G, B, and therefore 3 bits are set.
Bit parallel data can be transmitted.

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment of a data transmission system of the present invention.

FIG. 2 is a block diagram showing a configuration of an OSD light receiving unit of the data processing device of the system of FIG.

FIG. 3 is an explanatory diagram of a conventional method for connecting a video display device and a data processing device.

FIG. 4 is a diagram showing an example of an OSD signal.

FIG. 5 is an explanatory diagram of a blanking period included in an OSD signal.

FIG. 6 is an explanatory diagram of a display pattern of an OSD signal.

FIG. 7 is an explanatory diagram of an OSD signal display pattern.

FIG. 8 is an explanatory diagram of a display pattern of an OSD signal.

FIG. 9 is an explanatory diagram of the operation of the OSD light receiving unit of the data processing device.

FIG. 10 is an explanatory diagram of the operation of the OSD light receiving unit of the data processing device.

[Explanation of symbols]

 10 Video display device 11 Display unit 12 Encoder 13 OSD display control unit 14 Infrared light receiving unit 15 Data processing device 16 OSD light receiving unit 17 Decoder 18 Infrared light emitting unit 20 Condensing lens 21 RGB selection unit 22 Photodetector 23 Timing circuit 24 External light Identification circuit

Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI Technical display location H04B 10/10 10/22 10/00 H04B 9/00 C

Claims (6)

[Claims] 1. A data transmission system comprising a video display device having means for allocating a color to data to be transmitted corresponding to the content thereof, and means for displaying a graphic having the allocated color. 2. A means for optically reading a graphic displayed on the screen, which has a color assigned corresponding to the content of the data to be transmitted, and a read for reproducing the data to be transmitted. Data transmission system comprising a light receiving device having a means for analyzing the color of the formed graphic. 3. A video display device having means for allocating a color to data to be transmitted corresponding to the contents thereof, and means for displaying a graphic having the allocated color, and the displayed graphic optically. A data transmission system comprising: a light receiving device having a reading means and a means for analyzing the color of a figure read to reproduce the data to be transmitted. 4. The light receiving device includes a timing circuit that operates in synchronization with the video display device, a unit that detects a direct current level of light received in synchronization with a timing signal output from the timing circuit, and a detection circuit. And means for comparing the DC level which has been set to a predetermined value.
The data transmission system described in. 5. The light receiving device has means for subtracting an average value of the light receiving levels when the video display device is not displaying a graphic from the light receiving level when the video display device is displaying a graphic. The data transmission system according to claim 4, wherein: 6. Each bit of 3-bit data is R, G, B
6. The data transmission system according to claim 1, wherein the data transmission system is associated with each of the color signals.