POWER SAVING METHOD AND SYSTEM FOR DISPLAY DEVICE

摘要

PURPOSE: To energize a power saving function only in the interface side of a device by monitoring the change of a video signal at the interface of a display device and judging whether a controller main body is being used or not from the change. CONSTITUTION: An integration means 10 performs integrations with respect to the video signal of a prescribed position with a prescribed time interval. The comparing means 20 of a next stage judges whether the controller min body is being used or not based on integration values at two points of times. A power saving control part 30a is energized based on the compared result of the means 20. When the display device is a CRT device the control part 30a performs the cutting of a heater connection and the adjusting of contrast or the adjusting of brightness and in the case the display device is an analog liquid crystal display, the part 30a performs the lighting or the turning off of a back light or the adjusting of contrast or the adjusting of brightness. Moreover, in the case the display device is a digital liquid crystal display device, the part 30a lights a back light or turns off it.