Lighting device for fluorescent lamp
Patent 5130605 Issued on July 14, 1992. Estimated Expiration Date: 
March 4, 2011. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
March 4, 2011. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesDischarge lamp operating device Patent #: 4682080 InventorsAssigneeApplicationNo. 664223 filed on 03/04/1991US Classes:315/105, Pulsating or A.C. supply to the cathode or heater circuit315/101, Discharge device and/or rectifier in the cathode or heater circuit315/107, Automatic cut-out or voltage regulator in the cathode or heater circuit315/209RPERIODIC SWITCH IN THE SUPPLY CIRCUITExaminersPrimary: LaRoche, Eugene R.Assistant: Neyzari, Ali Attorney, Agent or FirmForeign Patent References
International ClassH05B 041/36Foreign Application Priority Data1990-03-07 JPAbstractA lighting device for a hot cathode fluorescent lamp used for a back light of a liquid crystal display or the like attempts to prolong the life of a lamp in a lighting device for a low consumption wattage fluorescent lamp. More specifically, the hot cathode fluorescent lamp is started while being pre-heated, and even after starting, a pre-heat current keeps flowing. The pre-heat current value after starting is set to be smaller than that at the time of starting for the purpose of optimizing the hot spot temperature. With employment of the configuration as described above, the lifetime of the hot cathode fluorescent lamp when used as a back light can extend to 10,000 hours or more.Field of SearchPulsating or A.C. supply to the cathode or heater circuitAutomatic cut-out or voltage regulator in the cathode or heater circuit Automatic cut-out or voltage regulator in the cathode or heater circuit WITH CATHODE OR CATHODE HEATER SUPPLY CIRCUIT Discharge device and/or rectifier in the cathode or heater circuit Condenser connected to plural cathodes or anodes of asymmetrical discharge device loads PERIODIC SWITCH IN THE SUPPLY CIRCUIT Periodic switch cut-out Plural periodic switches or multiple contact periodic switch Plural discharge devices and/or rectifiers in the supply circuit | |
