Nancy Chen

US Patent:

6844687, Jan 18, 2005

Filed:

Sep 26, 2003

Appl. No.:

10/672630

Inventors:

Nancy H. Chen - Salem MA, US

Assignee:

Osram Sylvania Inc. - Danvers MA

International Classification:

H05B 3700

US Classification:

315246, 315174, 315DIG 5

Abstract:

A method of operating a discharge lamp includes modulation of lamp power with a first longitudinal mode frequency to reduce segregation of the vapor phase species within the arc tube. The first longitudinal mode excitation frequency is determined by the acoustic response spectrum observed at an upper region of the arc tube when operated vertically. A frequency in an arc-straightening frequency range may also be added to the input power to straighten and center the arc.

US Patent:

6924604, Aug 2, 2005

Filed:

Sep 25, 2003

Appl. No.:

10/670647

Inventors:

Nancy H. Chen - Salem MA, US
Scott J. Butler - North Oxford MA, US
Joseph A. Olsen - Gloucester MA, US

Assignee:

Osram Sylvania Inc. - Danvers MA

International Classification:

H05B037/02

US Classification:

315209R, 315291, 315307

Abstract:

A discharge lamp system and method of operating a discharge lamp system in which vertical segregation of vapor phase species is reduced. Lamp power is modulated with an arc-straightening frequency and with a frequency that excites a combination radial plus longitudinal acoustic mode of the lamp. The combination radial plus longitudinal acoustic mode may be a combination first radial mode and nth longitudinal acoustic mode and may be excited with a single power frequency or a swept power frequency range. The two frequencies may be provided at the same time, or separately where the modulation at the arc-straightening frequency is 2 to 16 times longer than a subsequent modulation at the combination radial plus longitudinal acoustic mode.

US Patent:

7245075, Jul 17, 2007

Filed:

Apr 11, 2005

Appl. No.:

11/103080

Inventors:

Nancy H. Chen - North Andover MA, US
Joseph A. Olsen - Gloucester MA, US

Assignee:

Osram Sylvania Inc. - Danvers MA

International Classification:

H01J 17/20
H01J 61/12

US Classification:

313576, 313637, 313643, 313568, 313570

Abstract:

Metal halide lighting with good color during dimming may be obtained. An appropriate balance of commonly used metal halides (NaI, DyI, CeI, CaI, TlI) is dosed in the lamp. No mercury is used. A higher than typical xenon fill pressure from 50 to 500 Kilopascals may be used to help control thermal properties and voltage. If necessary, modulation of the power at acoustic resonance frequencies may be used to straighten and center the arc. Efficient and pleasant white output is obtained. As the power is reduced, the chromaticity either (1) remains fairly constant or (2) drifts acceptably towards warm pinkish colors. Large factors of attenuation in output can be realized. The lumen output was reduced by at least a factor of twenty in one sample as the power was dimmed from 70 to 20 watts.

US Patent:

7589477, Sep 15, 2009

Filed:

Sep 25, 2007

Appl. No.:

11/860759

Inventors:

Nancy H. Chen - North Andover MA, US
Joseph A. Olsen - Gloucester MA, US

Assignee:

OSRAM Sylvania Inc. - Danvers MA

International Classification:

H05B 37/00

US Classification:

315247, 315224, 315308

Abstract:

A method of controlling run-up of a metal halide lamp that has a nominal (full) light output during steady state operation and that has a current limit I, includes a lamp ballast sensing lamp current and voltage and calculating power, and evaluating requested power Pand requested current Ito operate the lamp at the nominal light output during run-up to steady state operation, supplying Ito operate the lamp when I≧I, and supplying Pto operate the lamp when I

US Patent:

7619362, Nov 17, 2009

Filed:

Aug 9, 2007

Appl. No.:

11/836559

Inventors:

Joseph A. Olsen - Gloucester MA, US
Nancy H. Chen - North Andover MA, US

Assignee:

OSRAM Sylvania Inc. - Danvers MA

International Classification:

H01J 17/18
G05F 1/00

US Classification:

313623, 313624, 313324, 313573, 315309, 315311, 315307, 315291

Abstract:

A method of detecting a leak in an outer jacket of a metal halide lamp having an arc tube inside the outer jacket and operated by a ballast, where the ballast monitors an electrical characteristic of the lamp during start and detects a leak in the outer jacket when the electrical characteristic deviates from that of a corresponding metal halide lamp whose outer jacket does not have a leak. The electrical characteristic is one of six markers, namely (1) V′(E) at a predetermined E, where V′(E) is a derivative of lamp voltage V as a function of cumulative energy E delivered to the ballast since ignition, (2) a value of E at which V′(E) reaches a maximum, (3) V at a predetermined E, (4) a local maximum of V′(E) up to a predetermined E, (5) a global maximum of V′(E), and (6) E required to achieve a predetermined V.

US Patent:

7633237, Dec 15, 2009

Filed:

Sep 25, 2007

Appl. No.:

11/860834

Inventors:

Nancy H. Chen - North Andover MA, US
Joseph A. Olsen - Gloucester MA, US

Assignee:

OSRAM SYLVANIA Inc. - Danvers MA

International Classification:

H05B 37/02

US Classification:

315224, 315291, 315246, 315209 R, 315DIG 2

Abstract:

A method of controlling run-up of a metal halide lamp that has a nominal (full) light output during steady state operation and that has a current limit I, includes, during run-up of the metal halide lamp to steady state operation, evaluating requested power Pand requested current Ito operate the lamp at the nominal light output Lduring the run-up, supplying Ito operate the lamp so long as I≧Iand supplying Pto operate the lamp when I

US Patent:

8198823, Jun 12, 2012

Filed:

Nov 20, 2009

Appl. No.:

12/622801

Inventors:

Nancy H. Chen - North Andover MA, US

Assignee:

Osram Sylvania Inc. - Danvers MA

International Classification:

H05B 37/02

US Classification:

315291, 315297, 315307

Abstract:

Techniques are disclosed that allow for the use of metal halide lamps in dimming applications, as well as other discharge lamps susceptible to dimming-induced chromaticity drift. Examination of such lamps reveals that some of the spectral changes that cause chromaticity drift during dimming are localized in narrow band regions of the spectrum, and lamp emission in these regions is enhanced (either increased or decreased) relative to the rest of the spectrum. Selective filtering of the enhanced emission caused by dimming can be used to reduce chromaticity shift. For instance, a filter deposited on and/or integrated into a lamp component (such as the arc tube, shroud, and/or outer jacket) operates to block transmission of those regions of the spectrum.

US Patent:

8378594, Feb 19, 2013

Filed:

Apr 29, 2010

Appl. No.:

12/769813

Inventors:

Nancy H. Chen - North Andover MA, US

Assignee:

Osram Sylvania Inc. - Danvers MA

International Classification:

H05B 37/02

US Classification:

315309, 315 50, 315117, 315118

Abstract:

Techniques are disclosed for controlling the light output of a lamp, where lamp efficacy is estimated as a function of estimated lamp temperature and instantaneous input power, or as a function of estimated lamp temperature only. Whether efficacy is estimated as a function of temperature and power, or as a function of temperature only can depend on changes in the lamp operating scenario. The techniques estimate lamp temperature by tracking energy input to and losses from (losses such as radiation, conduction, emission) the lamp arc tube, and determine the corresponding instantaneous light producing ability. The techniques may further be implemented to deliver the appropriate power command to obtain a desired light output. The techniques can be applied towards a general control in which arbitrary or custom light output vs. time paths are produced, and may be implemented by a processor programmed or otherwise configured to execute the desired control scheme.