JPH11282445A - Display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To freely shift the display device to a power-saving mode by itself by configuring it from a detection means to detect the presence or absence of a horizontal synchronizing signal and a vertical synchronizing signal, and a power-saving means to control to halt the power supply to a display circuit according to the presence or absence of these detected synchronizing signals. SOLUTION: A host system 1 sends image data based on the horizontal synchronizing signal and the vertical synchronizing signal. A display circuit 2 controls the image data sent from the host system 1 so that they are displayed. A display means 3 displays the image data controlled by the display circuit 2. A power circuit 6 supplies the power to the display means 3, the display circuit 2, and a power saving means 5. A detection means 4 detects the presence or absence of the horizontal synchronizing signal and the vertical synchronizing signal. And, the power saving means 5 controls to halt the power supply to the display circuit 2 according to the presence or absence of the horizontal synchronizing signal and the vertical synchronizing signal detected by the detection means 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device,
In particular, the present invention relates to a display device provided with power saving means.

[0002]

2. Description of the Related Art As shown in FIG.
The power saving means determines a power saving mode to be shifted based on the presence or absence of a synchronization signal output from the host system,
The interval before shifting to each power saving mode (S105, S108, S112) and the host system issuing a command to shift to the power saving mode to the device are set in advance in the host system, and the keyboard, mouse, etc. Counting is performed from the last time an input is made from a peripheral device for inputting data to the host system. In this case, the power-saving mode of the apparatus is controlled by giving a command to turn on / off the output of the synchronization signal to the host system.

[0003]

However, during the interval until the conventional display device enters the power saving mode,
Unnecessary normal operations can be performed and the power saving effect can be improved by shortening this interval.However, if you continue to stare at the screen without inputting, the screen will suddenly appear. Inconveniences such as disappearance occur, and a troublesome operation of inputting from the input peripheral device to the host system every time is required.

Further, if the power switch with the most power saving effect is turned off, the user must wait until the screen is displayed the next time the switch is turned on, and the host system detects the interruption from the user. If the host system itself does not have a function to turn on / off this synchronization signal, the type that turns on / off the output of the synchronization signal cannot be realized, so the power saving of the device is frequently performed. There is no means that can be used comfortably in the device itself.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a display device provided with means for freely switching to a power saving mode by itself.

[0006]

In order to solve the above-mentioned problems, a display device according to the present invention comprises: a host system for transmitting image data based on a horizontal synchronizing signal and a vertical synchronizing signal; A display circuit for displaying the image data controlled by the display circuit; a power supply circuit for supplying power to the display means and the display circuit; A detection means for detecting the presence / absence of a synchronization signal, and a power saving means for controlling power supply to the display circuit to be stopped according to the presence / absence of the horizontal synchronization signal and the vertical synchronization signal detected by the detection means. It is characterized by having been done.

[0007]

Next, 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 of a display device according to an embodiment of the present invention.

FIG. 2 is a flowchart of a display device according to an embodiment of the present invention.

A display device according to an embodiment of the present invention comprises:
As shown in FIG. 1, a host system 1 for transmitting image data based on a horizontal synchronizing signal and a vertical synchronizing signal, a display circuit 2 for controlling display of the image data transmitted from the host system 1, and a display circuit Display means 3 for displaying image data controlled by the circuit 2;
And a power supply circuit 6 for supplying power to the display circuit 2 and a detecting means 4 for detecting the presence or absence of a horizontal synchronization signal and a vertical synchronization signal.
And a power saving means 5 for controlling to stop the power supply to the display circuit 2 in accordance with the presence or absence of the horizontal synchronization signal and the vertical synchronization signal detected by the detection means 4.

Next, the operation of the display device according to one embodiment of the present invention will be described with reference to the drawings.

As shown in FIGS. 1 and 2, the operation of the display device according to the embodiment of the present invention is as follows. As shown in FIGS. When an interrupt from the switch of the save unit 5 is received, and when an interrupt from the switch is received in S16, it is determined in S17 whether or not the current mode is in the power saving mode forcibly shifted by the switch in S17. This is done by referring to the flag.

If the result of this determination is that the power saving mode has been forcibly shifted, the flag is cleared in step S18 and the mode is shifted to the normal operation mode. As a result of the determination, the power saving mode still forcibly shifted is set. If not in mode, S19
It is determined whether or not the apparatus is in the power saving mode which is shifted depending on the presence or absence of the synchronization signal.

Further, when the apparatus is in the power saving mode shifted according to the presence or absence of the synchronization signal, it returns from the interrupt in S20 to maintain the state of the power saving mode, and it has been found that the apparatus is not in the power saving mode. In this case, a flag is set in S21 to shift to the Suspend mode.
At this time, the program controlling the coloring of the LED is S1
The LED blinks at 3 to indicate that the display is in a forced power save mode.

Therefore, S10, S11, S12, S13
In the routine composed of the loop, the forcedly shifted Suspend mode is maintained as long as the horizontal synchronization signal and the vertical synchronization signal are both present, and either or both of the horizontal synchronization signal and the vertical synchronization signal disappear. If this is detected in S10 or S11, the flag is cleared in S14 or S8, and S5 or S9 or S in a normal power saving mode determined according to the lost synchronization signal.
Move to 22.

[0016]

As described above, according to the display device of the present invention, since the device can be shifted to the power saving mode in the normal operation mode, the host system can output the synchronization signal by setting the power management. This has the effect of preventing power consumption during the interval until the power is turned off.

Further, when the user keeps staring at the screen by shortening the interval set by the host system, the inconvenience of suddenly disappearing the screen is eliminated, and the host system is reused before shifting to the off mode. Unlike turning off the display device, the screen can be redisplayed quickly, and the synchronization signal output is turned on / off by detecting an interrupt from the user in the host system.
There is an effect that means for turning off can be reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram of a display device according to an embodiment of the present invention.

FIG. 2 is a flowchart of the display device according to the embodiment of the present invention.

FIG. 3 is a flowchart of a conventional display device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Host system 2 Display circuit 3 Display means 4 Detecting means 5 Power saving means 6 Power supply circuit

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI G09G 3/20 612 G06F 1/00 331C 332B

Claims (1)

[Claims] 1. A host system for transmitting image data based on a horizontal synchronization signal and a vertical synchronization signal, a display circuit for controlling display of image data transmitted from the host system, and a display circuit controlled by the display circuit. Display means for displaying image data; a power supply circuit for supplying power to the display means and the display circuit; detection means for detecting the presence or absence of the horizontal synchronization signal and the vertical synchronization signal; A display device, comprising: a power saving unit configured to control a power supply to the display circuit to be stopped according to presence / absence of a synchronization signal and a vertical synchronization signal.