U.S. Philips Corporation

Hitachi, Ltd.

Koninklijke Philips Corporation N.v.

Quarkstar LLC

Hans-Peter Stormberg

Louis Lerman

Hans-Gunther Ganser

Ralf Schafer

Yoshio Watanabe

Manfred Albach

Horst Dannert

Armin F Wegener

Hans-Helmut Bechtel

Erik Paul Boonekamp

Martinus Petrus Joseph Peeters

Teunis Willem Tukker

Egbert Lenderink

Peter Alexander Duine

Detlev F Hennings

Aldegonda Lucia Weijers

Martijn Henri Richard Lankhorst

Lingli Wang

Cornelis Jojakim Jalink

Marco Van As

Gunther Hans Derra

Oscar Arturo Chao Pujol

Klemens Brunner

Manfred Peterek

Jean Paul Jacobs

Guido Henri Maria Van Tartwijk

Isao Ochiai

A display device () comprising a plurality of lighting units (), each lighting unit comprising at least one light emitting diode () being provided with a fluorescent element () arranged to absorb at least part of the light emitted by said light emitting diode and emit light of a wavelength range different from that of the absorbed light is provided. The fluorescent element () comprises at least one phosphor being an europium(II)-activated halogeno-oxonitridosilicate of the general formula EaSiN:EuOX.

Display device with solid state fluorescent material

The invention relates to a dimming circuit arrangement for operating a high-pressure sodium lamp L with controllable color temperature. The lamp is supplied with current pulses having a controllable duty cycle D. A change in the color temperature can be achieved through a change .DELTA.D in the duty cycle D and a simultaneous change .DELTA.P in the power supplied to the lamp, while the relation .DELTA.D/.DELTA.P&gt;0 is satisfied.

Circuit arrangement for operating a high pressure sodium lamp

In a circuit arrangement for the operation of high-pressure gas discharge lamps by means of a pulsatory supply current having a pulse recurrence frequency between 50 and 2000 Hz and a duty cycle between 0.2 and 0.8, a current having a high-frequency between 20 and 200 kHz is superimposed on the current pulses and with a modulation ratio beween 0.3 and 1. The high-frequency is an integral multiple of the pulse recurrence frequency. Thus, flickering of the lamps is avoided.

Circuit arrangement for the operation of high-pressure gas discharge

A circuit arrangement for starting and operating gas discharge lamps with current of higher frequency comprises an electronic ballast unit connected to a direct voltage input source (2). An electronic switching element (3), which is controlled by a control device (8), is connected in series with an inductive element (4), and the discharge lamp (5). The lamp current flows through the inductive element from which a voltage is derived which is supplied to the control device as a supply direct voltage supply via a rectifier (14) and a smoothing capacitor (16). A first connection terminal of the smoothing capacitor is connected through a first ohmic resistor (18) to a first terminal of the direct voltage input source and a second connection of the capacitor is connected through the lamp (5) to a second terminal of the direct voltage input source.

Circuit arrangement for starting and operating gas discharge lamps

A plasma ion source comprises coaxially oriented electrodes of which a first electrode has the shape of a rod and a second electrode an annular shape, positioned in a space filled with a gas of atomic number greater than that of Boron, a current source up to 100 KA to be reacted within 1 usec and structure for focussing ions located near a formed pinch plasma.

Charged particle source of large current with high energy

In a circuit arrangement for starting and operating a high-pressure gas discharge lamp (8) by means of a voltage converter comprising at least one semiconductor switch (5, 6), which can be switched periodically to the conductive and to the non-conductive state by a control unit (32, 33, 34) in such a manner that the lamp receives a pulsatory supply current having an operating duty cycle between 0.1 and 0.7, the control unit (32, 33, 34) switches the semiconductor switch (5, 6) upon starting of the lamp (8) in such a manner that the duty cycle upon starting (starting duty cycle) is increased with respect to the operating duty cycle.

Circuit arrangement for starting a high-pressure gas discharge lamp

An X-ray lithography system comprises an X-ray source which forms a plasma, a band slit located between the X-ray source and a resist film such that a short slit side is parallel with a central axis of a plasma column, the long slit side being tilted with respect to said central plasma column axis.

X-ray lithography system

In a high-pressure gas discharge lamp having a discharge vessel containing an ionizable gas filling, consisting of translucent material and surrounded by a translucent outer envelope, which is adjoined at an end thereof by a lamp cap, the space between the discharge vessel and the said end of the outer envelope accomodates a thermally insulating porous translucent element consisting of a microporous aerogel.

High-pressure discharge lamp having a thermal insulating member

An electrochemical time switching device comprising a hollow body (1). The hollow body (1) is filled with a liquid electrolyte (12), in which a disintegrable anode (11) and a cathode (8) are arranged, between which a charge flows through the electrolyte (12) when a voltage is applied between the anode connection (6) and the cathode connection (7). An elastic sleeve (9) is arranged in the hollow body (1) between the anode connection (6) and the anode (11) and this sleeve encloses an electrical lead-in wire (10) interconnecting the anode connection (6) and the anode (11). The cross-section of the lead-in wire (10) is smaller than the cross-section of the anode (11) and its length is smaller than the length of the relieved sleeve (9).

Electrochemical time switching device

A circuit for operating high-pressure gas discharge lamps comprises a full-wave rectifier (2) which is connected to an alternating voltage supply source and supplies an output direct voltage to a combinatorial circuit part comprising a switching transistor (3), a choke coil (4), a fly-wheel diode (5) and a storage capacitor (6), from which the lamp is energized. A further combinatorial circuit part (7, 8, 10, 11) comprises at least one electronic circuit element (7) coupled between the storage capacitor (6) and the lamp (9) and is controlled by a control device (12). The control device compares an instantaneous lamp current of higher frequency with a nominal-value signal composed of a sinusoidal voltage component having double the supply frequency and a d.c. voltage component having a value of at least the maximum amplitude of the sinusoidal voltage.

Circuit arrangement for operating high-pressure gas discharge lamps

A circuit arrangement for A.C. operation of gas discharge lamps comprises a full-wave rectifier (1) connected to an alternating voltage source. The direct voltage is supplied to a combinatorial circuit part (3 to 8) in the form of a direct voltage converter, to which is connected a bridge circuit (9) which comprises four thyristors. The transverse branch of the bridge circuit includes the lamp (5). The full-wave rectifier (1) is followed by a smoothing capacitor (2) and an electronic switching element (14) is connected parallel to the bridge circuit (9). The switching element is switched to the conducting state in the vicinity of the zero passages of the input alternating voltage. As a result shortcircuits in the bridge circuit are avoided.

Circuit arrangement for A.C. operation of gas discharge lamps

A circuit arrangement for igniting and operating gas discharge lamps comprises a choke coil (1) connected between a lamp (2) and an a.c. supply source. The choke coil has an inductance L and an ignition device (3) is connected to the lamp. A capacitor (9) having a capacitance C is connected in parallel with at least a part of the choke coil in order to pass an ignition current to the lamp that is higher than the normal lamp operating current. The relationship betweeen the capacitive reactance of the capacitor and the inductive reactance of the choke coil is 1/.omega.C&gt;3.omega.L.

Growing community of inventors

Stolberg, Germany

Hans-Peter Stormberg