Aiming at the defect of safety of light source such as laser and intense pulsed light in current phototherapy technology

a low energy phototherapy method based on multi-band red light light-emitting diode（ LED） is proposed. Multi-band red light LED module of 630

830

940 nm are used as light source. The hardware control system is built using STM32 microprocessor as the core

and the circuit design and system implementation are given. By choosing different wavelengths

phototherapy function of different depth skin and tissue can be realized. And realtime monitoring and alarm of temperature of phototherapy part can be achieved. Illumination intensity and spot evenness of system are test to verify property of system. The results show that effective photo power density of the designed low energy phototherapy based on LED can reach 75 m W/cm~2

and the evenness of spot is above 0. 8.