JPH06308907A - Information display system and display device - Google Patents

Abstract

PURPOSE:To improve maintainability of a system by detecting failure of each display device itself and informing them, in a system using plural display devices which displays a computer signal, a character signal, a video signal or the like. CONSTITUTION:A signal source 10 outputs a signal to be displayed according to a control signal from a control device 20. Each display device 102-103 receives a display signal and displays it. At the time, sensors for quantity of light 111-113 detects quantity of light on screens, communication sections 121-123 converts them to data signals and outputs them. Next, a discriminating means 21 provided at the control device 20 discriminates an abnormal display device by the data signal, and displays a number of the abnormal display device by a display means 30.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device for displaying computer signals, character signals, video signals, etc., and an information display system using a plurality of such display devices.
In particular, it relates to an in-vehicle information display system that provides information on a train.

[0002]

2. Description of the Related Art Conventionally, as a system for providing information in a vehicle, there is a display system in which a plurality of liquid crystal display devices are arranged to provide information such as destination guidance, advertisement of publicity, or teletext.

[0003] As a conventional example for displaying information in a vehicle using a liquid crystal display device, there is a "small television CM video" described in Nihon Keizai Shimbun on January 21, 1992.

[0004]

In the above-mentioned conventional example, no consideration is given to measures for failure of each display device, and it is necessary to inspect all display devices by human eyes.

For example, in the case of a train, each vehicle has 10 to 20
If there are 10 display devices and 10 trains are operated, it is necessary to monitor a total of 100 to 200 display devices, which causes a problem that the burden on the crew member increases.

[0006]

In order to solve the above problems, in the present invention, each display device is provided with a sensor and a communication unit for monitoring the brightness of the display device.

[0007]

The above-mentioned sensor detects the brightness of the display device, and when there is an abnormality, the communication unit generates a signal notifying the abnormality and notifies the crew member. Therefore, the crew does not need to monitor a large number of display devices, which has the effect of reducing the burden on the crew.

[0008]

FIG. 1 is a block diagram of the first embodiment of the present invention. Reference numeral 10 is a signal source, 20 is a control device, 21 is a discrimination means provided inside the control device 20, 30 is a display means,
Reference numerals 101 to 103 are display devices, 111 to 113 are light amount sensors attached to the display devices, and 121 to 123 are communication units.

The operation of each block will be described below. The signal source 10 outputs a signal to be displayed according to a control signal from the control device 20. Each of the display devices 101 to 103 receives the display signal and displays it. At this time, each display device 101-
Light intensity sensors 111 to 113 attached to 103 detect the light intensity of the screen, and the communication units 121 to 123 convert the data signals and output them. Next, the discriminating means 21 provided in the control device 20 discriminates the abnormal display device from the data signal, and the display means 30 displays the number of the abnormal display device. At this time, the display means 30 can be composed of a display board such as a red-green lamp or a display monitor. Now, an actual configuration example of the display devices 101 to 103 and the light amount sensors 111 to 113 and a specific circuit configuration example of the communication units 121 to 123 and the determination unit 21 will be described below with reference to the drawings.

FIG. 2 shows a configuration example of the display devices 101 to 103 and the light amount sensors 111 to 113. 104 is a display screen of the display devices 101 to 103, 114 is a light amount sensor 11
The light receiving units 1 to 113.

As shown in the figure, the light amount sensors 111 to 113 are provided.
Is provided on the left side of the display screen 104, for example.
4 is covered so as not to be affected by outside light. The light receiving unit 114 detects the brightness of the display screen 104 and outputs it to the communication units 121 to 123.

FIG. 3 shows a circuit configuration example of the communication section 121 and the discrimination means 21. The communication unit 121 is the A / D converter 12
4 and a parallel-serial converter 125. The discriminating means 21 includes a serial-parallel converter 221, a subtractor 222, reference value setting circuits 223, 224, comparators 225, 226, an inverter 227, and an OR gate 228.

The communication section 121 converts the output voltage of the light quantity sensor 112 into a digital signal and then outputs the data in series.

On the other hand, in the discriminating means 21, the serial data is received by the serial-parallel converter 221, and returned to parallel data. Next, the subtracter 222 calculates the difference between the parallel data and the reference value generated by the reference value setting circuit 223 according to the video signal input to the display device. The difference and the reference value generated by the reference value setting circuit 224 are compared by the comparators 225, 22.
Compare by 6. At this time, since the positive / negative of the difference is unknown, two comparators are used, and the comparator 226 compares it with the complement of the reference data and ORs the outputs of both comparators.
As a result, it is possible to detect a large deviation from the preset reference, that is, a failure.

As described above, according to this embodiment, in a system using a plurality of display devices for displaying computer signals, character signals, video signals, etc., a light amount sensor and a communication unit are provided in each display device, By providing the discriminating means in the above, it is possible to detect an abnormality in the brightness of the display device, and thus maintainability is improved.

FIG. 4 is a block diagram of a display device according to the second embodiment of the present invention. 40 is a liquid crystal panel, 50 is a backlight, and 60 is a light amount sensor. Since the entire system configuration is the same as that of the first embodiment, the repetitive description will be omitted.

In this embodiment, a liquid crystal display device is used as a display device, and a light quantity sensor 60 is arranged between the liquid crystal panel 40 and the backlight 50. Thus, the failure of the backlight can be detected as in the first embodiment, and further the failure of the liquid crystal panel can be detected.
A liquid crystal panel failure detection method will be described below with reference to the drawings.

FIG. 5 shows an example of voltage-luminance characteristics of the liquid crystal panel. From the figure, it can be seen that when the applied voltage to the liquid crystal panel is increased, the brightness, that is, the transmittance is decreased. That is, the liquid crystal panel acts as a shutter for light. In the case of normal display, the transmittance of the light of the backlight is considered, but the external light from the liquid crystal surface also acts as a shutter to limit the transmission of the external light. Therefore, turn off the backlight,
If the brightness of the back surface of the liquid crystal panel is measured, the relationship of FIG. 5 is established. Therefore, in this embodiment, the brightness around each display device is kept constant, the applied voltage of the liquid crystal panel is changed with the backlight off, and the brightness is measured by the light amount sensor. Accordingly, if a liquid crystal panel having a transmittance greatly different from those of other displays is detected, the failure of the liquid crystal panel can be detected.

As described above, according to the present embodiment, when the liquid crystal display device is used as the display device, not only the failure of the backlight but also the failure of the liquid crystal panel itself can be detected.

In addition to the liquid crystal display device, the ECD (Electro
It is also possible to detect failures with light valve type display devices such as chomic displays.

FIG. 6 shows a block diagram of the third embodiment of the present invention. 201 to 203 are display devices, 211 to 213 are temperature sensors, and 22 is a discriminating means. The other blocks are the same as those in the first embodiment, and therefore their repetitive description will be omitted.

In this embodiment, each display device is provided with a temperature sensor for detecting the ambient temperature, and each display device is turned on / off according to the temperature.
It controls the OFF operation.

FIG. 7 shows a circuit configuration example of the discrimination circuit of this embodiment. 271 is a D / A converter, 272, 273 are comparators, 274 is a low temperature side reference voltage generation circuit, 275 is a high temperature side reference voltage generation circuit, and 276 is an AND gate. Since the other blocks are the same as those in the first embodiment, the repetitive description will be omitted.

In this embodiment, the signal output from the communication section is serial-parallel converted, and further converted into an analog signal by the D / A converter 271. First, the comparator 272 compares the voltage of the analog signal with the reference voltage generated by the low temperature reference voltage generation circuit 274, and outputs the result. Also, the comparator 2
Reference numeral 73 denotes a voltage of the analog signal and the high temperature reference voltage generation circuit 27.
5 is compared with the reference voltage generated, and the result is output. At this time, the low temperature reference voltage generation circuit 274 outputs the lower limit value of the operating temperature of the display device, and the high temperature reference generation circuit 275 outputs the upper limit value of the operating temperature of the display device. Therefore, when the detected temperature falls within the operating temperature range, the output of the AND gate 276 becomes Hi level. At this time, the control device turns on the power of each display device. On the other hand, when the detected temperature is outside the operating temperature, the output of the AND gate 276 becomes L
It becomes the o level and the power supply of each display device is turned on by the control device.
Try to FF. At the same time, this ON-OFF information is displayed by the display means 30.

As described above, according to the present embodiment, the temperature sensor for monitoring the ambient temperature of the display device is provided and the display is performed only within the operating temperature range. Can be automatically prevented and ON
-OFF information can be confirmed at a glance.

FIG. 8 shows a block diagram of the fourth embodiment of the present invention. Reference numerals 301 to 303 are display devices, 311 to 313 are surveillance cameras, 321 to 323 are detection means, and 23 is a determination means. Since the other blocks are the same as those in the first embodiment, the repetitive description will be omitted.

In this embodiment, the surveillance cameras 311 to 311 are inspected at the time of inspection.
313 photographs the screen of each display device, and the detection means 321 to
An image processing unit 323 performs image processing to detect display contents and display brightness. The communication unit transmits the detection data, the discriminating unit 23 detects the abnormality, and the display unit 30 displays the abnormality.

Further, in this embodiment, when failure detection is not performed, the situation around the display device is monitored by the monitoring cameras 311 to 31 1.
3 is photographed, and the detecting means 321 to 323 detect the contour of the person to obtain the congestion degree. The congestion degree data is transmitted to the discriminating means 23 to discriminate a vacant (or crowded) place, and the control device 20 operates the signal source so as to perform a display notifying the vacant place.

As described above, according to this embodiment, the surveillance camera for photographing the display contents of each display device in the information display system,
By providing the detection circuit for detecting the display content and the display brightness by the image processing from the image of the surveillance camera, and the determination means for detecting the abnormality of each display device from the data of the detection circuit,
Maintainability is improved.

Further, according to the present embodiment, the degree of congestion is detected by the monitoring camera and the detection means provided in each display device, and the controller displays a message according to the degree of congestion.
The degree of congestion can be eased.

Although the congestion degree is detected by the image processing of the surveillance camera in this embodiment, the congestion degree may be detected by the total weight in the case of a train or an elevator.

FIG. 9 shows a block diagram of the fifth embodiment of the present invention. A display device 70 includes a display panel 40, a backlight 50, and the display panel 40 and the backlight 50.
Between the light amount sensor 60, the control circuit 701, the discrimination means 702 provided inside the control circuit, and the display means 7.
It is composed of 03.

The control circuit 701 receives a display signal from the signal source 10 and generates data to be displayed on the display panel 40 and a clock for operating the display panel 40. Further, the control circuit 701 also controls ON / OFF of the backlight 50.

In this embodiment, the light amount sensor 6 is provided in the display device 70.
0, a discriminating means 702 and a display means 703 are provided so as to detect and inform the failure of itself. The light amount sensor 60 detects the brightness of the backlight and the transmittance of the display panel, as in the second embodiment. The discriminating means 702 discriminates the abnormality from the detected data and indicates whether or not there is an abnormality by the LED
It is displayed by a display means 703 such as a (light emitting diode) lamp. The discriminating means 702 is the same as that of the first embodiment, so that the repetitive description will be omitted.

As described above, according to the present invention, since the light amount sensor, the judging means and the displaying means are provided in the display device, the user can confirm the failure of the display panel and the life of the backlight at a glance.

In this embodiment, an example in which an LED lamp or the like is provided as the display means is shown, but the result of the discrimination means may be displayed directly on the display panel by the control circuit.

[0037]

According to the present invention, in a system using a plurality of display devices for displaying computer signals, character signals, video signals, etc., by providing a light amount sensor and a communication unit in each display device, Since the abnormality in the brightness of the display device can be detected, the maintainability is improved.

Further, according to the present invention, in a system using a plurality of display devices for displaying computer signals, character signals, video signals, etc., a temperature sensor for monitoring the ambient temperature of each display device is provided, and the operating temperature is By performing the display only within the range, it is possible to prevent unstable display at low temperature or high temperature.

Further, according to the present invention, in a system using a plurality of display devices for displaying computer signals, character signals, video signals, etc., surveillance cameras for photographing the display contents of the respective display devices, and images of the surveillance cameras. By providing the detection circuit for detecting the display content and the display brightness by the image processing and the discrimination means for detecting the abnormality of each display device from the data of the detection circuit, the maintainability is improved. Also, by taking a picture of the surroundings of each display device by the surveillance camera and detecting the congestion degree from the image of the camera, according to the congestion degree of each display device, a message or the like indicating a vacant place is displayed, etc. You can easily take measures to reduce congestion.

[Brief description of drawings]

FIG. 1 is a block diagram of a first embodiment of the present invention.

FIG. 2 is a configuration diagram showing an example of a display device and a light amount sensor in the block of FIG.

3 is a block diagram showing a circuit configuration example of a communication unit and a determination unit of the block of FIG.

FIG. 4 is a configuration diagram of a second embodiment of the present invention.

FIG. 5 is a principle diagram of a second embodiment of the present invention.

FIG. 6 is a block diagram of a third embodiment of the present invention.

FIG. 7 is a block diagram showing an example of a circuit configuration of a block discriminating means in FIG.

FIG. 8 is a block diagram of a fourth embodiment of the present invention.

FIG. 9 is a block diagram of a fifth embodiment of the present invention.

[Explanation of symbols]

 10 ... Signal source, 20 ... Control device, 21-23 ... Discrimination means, 30 ... Display means, 40 ... Liquid crystal panel, 50 ... Backlight, 60 ... Light quantity sensor.

Claims (5)

[Claims] 1. An information display system comprising a display device, a signal source for supplying a signal to be displayed on the display device, and a control device for controlling the display device or the signal source, or both of them. A brightness sensor for detecting the brightness of the display device, a communication unit for converting the output of the brightness sensor into a data signal and transmitting the data signal, and a determination unit for determining an abnormality of each display device based on the data signal from the communication unit. An information display system comprising: a display unit that displays the determination result of the determination unit. 2. A display device comprising a light valve type display panel, a drive circuit for driving the display panel, and a backlight, wherein the brightness of external light passing through the display panel is between the display panel and the backlight. A display device provided with a light amount sensor for detecting. 3. An information display system comprising a display device, a signal source for supplying a signal to be displayed on the display device, and a control device for controlling the display device, the signal source, or both, each display device. A temperature sensor that detects the ambient temperature of the device, a communication unit that converts the output of the temperature sensor into a data signal and transmits the data signal, and a data signal from the communication unit, and when the temperature is within the operating temperature of the display device. An information display system comprising: a control unit that operates each display device and stops the operation of each display device when the temperature is outside the operating temperature. 4. An information display system comprising: a display device; a signal source for supplying a signal to be displayed on the display device; and a control device for controlling the display device or the signal source, or both of them. Image input device for monitoring the surrounding conditions of the image processing device, image processing means for processing a signal obtained from the image input device, a communication part for transmitting the output of the image processing means, and a signal sent from the communication part of the display device. An information display system comprising: a control unit that changes the content displayed on each display device based on the above. 5. A display device comprising a light valve type display panel, a drive circuit for driving the display panel, and a backlight, wherein the brightness of the backlight and the display panel are transmitted between the display panels. A light amount sensor that detects the brightness of external light, a determination unit that determines the output data of the light amount sensor, and detects the life of the backlight, a failure of the display panel, and the like, and a display that displays the results determined by the determination unit. And a means for providing the display device.