Method for modulating light at set time for smart LED lamp without clock apparatus

The invention discloses a method for modulating light at a set time for a smart LED lamp without clock apparatus. The method comprises the following steps: 1) connecting a cell phone with the LED lamp in a wireless connection manner; 2) conducting time synchronization; 3) setting a timing function; and 4) outputting at a set time: when a one-chip microcomputer receives the order to modulate light at a set time, a PWM outputting means is adopted to control the LED light source. According to the duty ratio of the PWM, the brightness of the LED light source can be modulated in the range of 0-100%; a multi-channel PWM output allows the full color change; brightness and color transitions can be changed by the control of change in pulse width in PWM. These actions bring about different starting effects. According to the invention, the system for performing the method is simple in structure and cost-effective to make. Without additional hardware cost, light modulation functions can be achieved for single group of la