Patents by Inventor Joe Chiu Pong Liu

Joe Chiu Pong Liu has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7122972
    Abstract: An AC to AC power conversion apparatus with constant power feeding characteristics to fluorescent lamp or FD lamp is described. The constant power characteristic is achieved by discontinuous mode operation of capacitor coupled in series with the load. Packets of energy are pumped out to the load in each switching cycle, regardless of the resonant characteristics. The dependence of the input power on the square of the supply voltage make the input resistive and produces good power factor automatically. The lamp load is dimmable by external phase control dimmer like resistive incandescent lamps. Multiple lamp loads with different power rating can be integrated by adding more sets of said capacitors and associated components.
    Type: Grant
    Filed: March 10, 2004
    Date of Patent: October 17, 2006
    Assignee: University of Hong Kong
    Inventors: Franki Ngai Kit Poon, Man Hay Pong, Joe Chiu Pong Liu