Patent · US Expired

Electrodeless low pressure lamp with multiple ferrite cores and coils

US6605889B2 · kind B2 · utility

2Cited by
1References
24Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 24, 2001
Grant dateAug 12, 2003
Priority date
Expiry dateMar 20, 2022

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01J61/523
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

An electrodeless low pressure discharge lamp comprises an envelope made from a straight tube and a reentry cavity sealed to one of tube's ends. The cavity has several hollow ferrite cores separated from each other with a few mm distance. Each ferrite core has an induction coil of few turns wound around the core. Each cavity has a cooling copper tube or rod located inside the ferrite core that removes heat from the cores and dumps the heat into a heat sink welded to the cooling tube/rod thereby keep the temperature of the ferrite cores below their Curie point. Each induction coil is electrically connected to the matching network while all matching networks are connected in parallel to the high frequency power source (driver). Inductively coupled plasmas generated in the envelope by several core/coil assemblies produce axially uniform UV and visible radiation.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.