SINUSOIDAL DRIVE SYSTEM AND METHOD FOR PHOTOTHERAPY
摘要
The LEDs in a phototherapy LED pad are controlled so that the intensity of the light varies in accordance with a sinusoidal function, thereby eliminating the harmonics that are generated when the LEDs are pulsed digitally, in accordance with a square-wave function. This is accomplished analogically by using a sinusoidal wave to control the gate of a MOSFET connected in series with the LEDs or by using a digiltal-to-analog converter to control the gate of the MOSFET with a stair step function representative of the values of a sinusoidal function at predetermined intervals. Alternatively, pulse-width modulation is used to control the gate of the MOSFET in such a way that the average current through the LEDs simulates a sinusoidal function. In additional to using a simple sine wave function, the LED current may also be controlled in accordance with "chords" containing multiple sine waves of different frequencies.
申请公布号
WO2015123379(A1)
申请公布日期
2015.08.20
申请号
WO2015US15547
申请日期
2015.02.12
申请人
APPLIED BIOPHOTONICS LTD.;WILLIAMS, RICHARD, K.
发明人
WILLIAMS, RICHARD, K.;LIN, KENG, HUNG;SCHELL, DANIEL;LEAHY, JOSEPH, P.