US Patent No. 10,772,175

LIGHTING APPARATUS


Patent No. 10,772,175
Issue Date September 08, 2020
Title Lighting Apparatus
Inventorship Wei wei Liu, Fujian (CN)
Hong Kui Jiang, Fujian (CN)
Assignee XIAMEN ECO LIGHTING CO. LTD., Xiamen (CN)

Claim of US Patent No. 10,772,175

1. A lighting apparatus, comprising:a first light source for emitting a first light with a first optical parameter;a second light source for emitting a second light with a second optical parameter;a current source for generating a driving current;
a pulse width modulation (PWM) circuit for generating a PWM signal;
a switch circuit for guiding the driving current to either the first light source or the second light source by reference to the PWM signal so as by mixing the first light of the first optical parameter and the second light of the second optical parameter to obtain a desired mixed output light of a mixed optical parameter, wherein switch circuit comprises:
a first switch unit connected in series with the first light source forming a first light path, a control pate of the first switch unit receiving the PWM signal;
a second switch unit connected in series with the second light source forming a second light path, the second light path being connected with the first light path in parallel; and
a one-way conductive unit with a first terminal connected to a control pate of the second switch unit and a first output terminal of the current source, a second terminal of the one-way conductive unit being connected between the first switch unit and the first light source; wherein the switch circuit further comprises:
a first voltage divider comprising a first voltage divider resistor and a second divider resistor connected with the first light path in parallel, wherein the control gate of the first switch unit is connected between the first voltage divider resistor and the second voltage divider resistor;
a second voltage divider comprising a fourth voltage divider resistor and a fifth voltage divider resistor and being connected with the second light path in parallel, wherein the control gate of the second switch unit is connected between the fourth voltage divider resistor and the fifth voltage divider resistor; and
a third voltage divider comprising a third voltage divider resistor, the third voltage divider resistor being connected between a second terminal of the one-way conductor and a second output terminal of the current source.