Patent ID: 8723854

Claim:
A digital photo frame with power saving functions comprising: a display panel; a power generation unit for providing system power and switching the system power according to a power control signal; a passive infrared sensor, installed in the display panel, for detecting whether a user exists within a specific range by detecting changes in infrared radiation occurring when there is movement by the user whose temperature is different from surroundings of the digital photo frame, to generate a user detection signal; a power control unit, coupled to the power generation unit and the central processing unit, for generating the power control signal to control the power generation unit; and a central processing unit, coupled to the power generation unit, the passive infrared sensor and the power control unit, for executing: computing a first idle time of the digital photo frame according to a user trigger signal and determining whether the first idle time is greater than a first default value; switching on the passive infrared sensor when the first idle time is greater than the first default value; computing a second idle time of the digital photo frame according to the user detection signal indicating that the user is not within the specific range or the user trigger signal and determining whether the second idle time is greater than a second default value; switching off a backlight of the display panel when the second idle time is greater than the second default value; computing a third idle time of the digital photo frame according to the user detection signal indicating that the user is not within the specific range or the user trigger signal and determining whether the third idle time is greater than a third default value; and switching off the system power of the digital photo frame when the third idle time is greater than the third default value.