Patents by Inventor Tsuji Hidetoshi

Tsuji Hidetoshi 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).

  • Power regulator of discharge lamp and variable color illumination apparatus using the regulator
    Patent number: 5491388
    Abstract: A current supplied to a discharge lamp (100) is an A.C. current having a predetermined frequency from an inverter circuit (70), and its power control is carried out by changing the current setting (setting signal) of a chopper circuit (40) constituting a constant current circuit. When a value is set by an output luminance regulator (120), this set current value is inputted to a chopper control circuit (130). The chopper control circuit (130) checks the current detected by a current detector (110) and outputs a current control to a gate terminal (41) of the chopper circuit (40) so that the output current may coincide with the set current value. Accordingly, the power supplied from the inverter circuit (70) to the discharge lamp (100) is controlled by the chopper circuit (40).
    Type: Grant
    Filed: September 22, 1994
    Date of Patent: February 13, 1996
    Assignee: Toto Ltd.
    Inventors: Yamada Nobuyuki, Douke Takahiro, Tsuji Hidetoshi