The lens cap assembly for projector includes power switch, lens cap, transmission unit, detection and clkosing unit, detection and opening unit and control unit connected to the power switch and the other units. When the power switch is turned on or off, the control unit will rotate the transmission unit to make the lens cap move forwards or backwards. When the lens cap touches with the detection and closing unit or the detection and opening unit, the control unit will stop the transmission unit to open or close the lens cap. |