Abstract: A portable electronic device and an operation method using the portable electronic device include presetting function modes applicable to specific user interfaces of the portable electronic device, and presetting operations in each of the function modes and a command corresponding to each of the operations. Signals are detected from a first and a second proximity sensors of the portable electronic device, and a time length of each signal is calculated. A command corresponding to a current operation is executed if the current operation is determined to accord with one of the preset operations according to the detected signals and the time length.

Abstract: An electronic device and a method enables an unlock operation of the electronic device. When the electronic device in a lock state is moved for the unlock operation, the electronic device receives a three-axis acceleration vector of the electronic device from an accelerometer. The electronic device analyzes three movement directions of the electronic device along three coordinate axes. The electronic device determines whether the analyzed three movement directions are the same as three predetermined movement directions along the three coordinate axes. If the analyzed three movement directions are the same as the three predetermined movement directions along the three coordinate axes, the electronic device is changed from the lock state to an unlock state.

Abstract: A method for adjusting backlight includes a series of operations. Providing a portable electronic device (10), the portable electronic device including an image sensor (12), a signal processor (14), a backlight adjuster (16) and a backlight module (18), which are all electronically connected together. The image sensor senses an outside light and transforms the sensed outside light to an optical image signal, and sends the optical image signal to the signal processor. The signal processor determines the backlight intensity that the backlight module should provide according to the received optical image signal, and sends a control signal to the backlight adjuster. The backlight adjuster dynamically adjusts the backlight provided by the backlight module based on the control signal sent from the signal processor. A portable electronic device is also disclosed.