Display device and controlling method thereof

A controlling method of a display device, the display device comprising a micro-controller, a time controller and a memory unit, the controlling method comprising:

• storing a time reference value, a plurality of preset period criteria and a plurality of operation mode data in the memory unit, wherein each of the preset period criteria relates to each of the operation mode data;
• utilizing the time controller to read the time reference value and a plurality of the preset period criteria, comparing the time reference value and a plurality of the preset period criteria to determine the preset period criterion corresponding to the time reference value, and selecting the operation mode datum corresponding to the preset period criterion;
• and
• utilizing the micro-controller to set a plurality of setting values of the display device according to the operation mode datum selected by the time controller.