Lauren D Dymond

US Patent:

63135876, Nov 6, 2001

Filed:

Nov 5, 1999

Appl. No.:

9/434310

Inventors:

Donald A. MacLennan - Gaithersburg MD
Lauren E. Dymond - North Potomac MD
Aleksandr Gitsevich - Montgomery Village MD
William G. Grimm - Silver Spring MD
Kent Kipling - Gaithersburg MD
Douglas A. Kirkpatrick - Great Falls VA
Samuel A. Ola - Silver Spring MD
James E. Simpson - Gaithersburg MD
William C. Trimble - Columbia MD
Peter Tsai - Olney MD
Brian P. Turner - Damascus MD

Assignee:

Fusion Lighting, Inc. - Rockville MD

International Classification:

H05B 4116

US Classification:

315248

Abstract:

A high frequency inductively coupled electrodeless lamp includes an excitation coil with an effective electrical length which is less than one half wavelength of a driving frequency applied thereto, preferably much less. The driving frequency may be greater than 100 MHz and is preferably as high as 915 MHz. Preferably, the excitation coil is configured as a non-helical, semi-cylindrical conductive surface having less than one turn, in the general shape of a wedding ring. At high frequencies, the current in the coil forms two loops which are spaced apart and parallel to each other. Configured appropriately, the coil approximates a Helmholtz configuration. The lamp preferably utilizes an bulb encased in a reflective ceramic cup with a pre-formed aperture defined therethrough. The ceramic cup may include structural features to aid in alignment and I or a flanged face to aid in thermal management. The lamp head is preferably an integrated lamp head comprising a metal matrix composite surrounding an insulating ceramic with the excitation integrally formed on the ceramic.

US Patent:

20020079845, Jun 27, 2002

Filed:

Feb 6, 2001

Appl. No.:

09/776698

Inventors:

Douglas Kirkpatrick - Great Falls VA, US
Gary Bass - Mt.Airy MD, US
Jesse Copsey - Germantown MD, US
Lauren Dymond - North Potomac MD, US
William Garber - Poolesville MD, US
Aleksandr Gitsevich - Montgomery Village MD, US
William Grimm - Silver Spring MD, US
Vincent Kwong - Vancouver, CA
Izrail Levin - Silver Spring MD, US
Donald MacLennan - Gaithersburg MD, US
Samuel Ola - Forest VA, US
James Proctor - Monrovia MD, US
Robert Roy - Frederick MD, US
James Simpson - Gaithersburg MD, US
Paul Steiner - Olney MD, US
Peter Tsai - Olney MD, US
Brian Turner - Damascus MD, US

International Classification:

H05B041/16

US Classification:

315/248000, 315/246000, 315/005000

Abstract:

An ultra bright, low wattage inductively coupled electrodeless aperture lamp is powered by a solid state RF source in the range of several tens to several hundreds of watts at various frequencies in the range of 400 to 900 MHz. Numerous novel lamp circuits and components are disclosed including a wedding ring shaped coil having one axial and one radial lead, a high accuracy capacitor stack, a high thermal conductivity aperture cup and various other aperture bulb configurations, a coaxial capacitor arrangement, and an integrated coil and capacitor assembly. Numerous novel RF circuits are also disclosed including a high power oscillator circuit with reduced complexity resonant pole configuration, parallel RF power FET transistors with soft gate switching, a continuously variable frequency tuning circuit, a six port directional coupler, an impedance switching RF source, and an RF source with controlled frequency-load characteristics. Numerous novel RF control methods are disclosed including controlled adjustment of the operating frequency to find a resonant frequency and reduce reflected RF power, controlled switching of an impedance switched lamp system, active power control and active gate bias control.