Abstract: Provided is a backlight assembly and a display apparatus having the same, the backlight assembly including: a power converter which includes a transformer and converts a level of input power; a power factor corrector which corrects a power factor of original power and outputs it to the power converter; and a light source driver which is connected to a secondary coil of the transformer and includes a first light emitting diode module, a second light emitting diode module, and a current supplying circuit which balances amperage of power supplied to the first light emitting diode module and the second light emitting diode module.

Abstract: The invention provides a power supply or drive circuit for a pulsed flashlamp which utilizes a two-core component having common windings as both an inductor for arc mode drive and for breakdown triggering of the lamp. Discharge of a capacitor through the inductor and lamp is controlled by a high-speed semiconductor switch which is turned on and off by a suitable control, current flowing from the inductor through a one-way path including the lamp when the switch is off. The control maintains the ratio of the power variation through the lamp to the average power through the lamp substantially constant. The controls may also be utilized to control output pulse shape. Novel protective features are also provided for circuit components during turn on periods for the switch.

Abstract: The method of invention provides a multicast service from an information delivery apparatus to wireless terminals through wireless routes. The method includes the step of transmitting, from the information delivery apparatus, a plurality of sets of multicast information, wherein these sets are identical to each other as to contents thereof but differ in transmission conditions. The method further includes the step of receiving, at any given one of the wireless terminals, one of the sets of multicast information being transmitted under one of the differing transmission conditions.

Abstract: A diversity combiner includes a plurality of branch receiving sections each receiving a QPSK modulation signal and a vector combiner. Each of the branch receiving sections includes a level detector which detects a signal level from the QPSK modulation signal, a phase difference detector which detects a phase difference from the QPSK modulation signal in each bit interval, and a data transformer which transforms polar data consisting of the signal level and the phase difference into rectangular data consisting of two rectangular coordinate values. The rectangular data obtained by the each branch receiving sections is combined by the vector combiner to produce combined rectangular data which is in turn transformed to combined polar data.

Abstract: A projector lamp comprising a single ended metal halide discharge lamp in a generally spherical reflector has been found to exhibit turbulence when running. The resulting fluctuation of light especially when used in conjunction with the reflector to concentrate the light for studio or theatre applications provides an apparent movement which is extremely disturbing to the eye. It has been found the turbulent movement of gas around the electrodes in the lamp envelope can be regularised by the application of a magnetic field to the envelope. The turbulence is sensitive to conditions within the discharge arc tube and the strength and position of the magnetic field has to be variable to cater for this. The magnetic field is conveniently applied by an electro-magnet using lamp current.

Abstract: The radiant emission of a mercury-argon discharge in a fluorescent lamp assembly (10) is enhanced by providing means (30) for establishing a magnetic field with lines of force along the path of electron flow through the bulb (12) of the lamp assembly, to provide Zeeman splitting of the ultraviolet spectral line. Optimum results are obtained when the magnetic field strength causes a Zeeman splitting of approximately 1.7 times the thermal line width.

Abstract: A compact fluorescent lamp with a screw-in plug to fit conventional screw sockets which operates at 20-30 watts and provides the lumen output of a 75-100 watt lamp. The lamp is essentially a hollow cylinder with a glass envelope for the two outer walls. The space between the two outer walls is partitioned to constrain the arc discharge to follow a designated path around the inner surface of the lamp. Efficiency is promoted by novel ballast design. The screw-in fluorescent lamp contains a coil in the center of the lamp which creates a diverging magnetic field which causes the arc discharge to spread and may also serve the dual purpose of limiting arc current. Arc spreading coils of several designs are disclosed to provide oriented diverging magnetic fields, rotating diverging magnetic fields and magnetic fields shaped to the lamp envelope with which they are employed.

Abstract: A circuit interrupting device for providing protection against surge currents is constructed to operate very rapidly. A surge current generates a magnetic field in coils which deflects an electron beam which normally travels from a cathode to an anode to complete an electric circuit.

Abstract: A discharge lamp with minimized upward bowing of the arc in which conductors carrying full arc current are placed in close proximity above and below the arc tube. The conductors run parallel with the longitudinal axis of the arc tube and the conductors above the arc are electrically connected in such a manner as to carry full lamp current in the opposite direction of the arc, thus repelling the arc in a downward direction, and the conductor or conductors below the arc tube are electrically connected so as to carry full lamp current in the same direction of the arc, thus attracting the arc downward.

Abstract: A high voltage switching system switches large load currents in short periods. Gas is contained within an envelope at a pressure of the order of magnitude of at least 0.1 atmosphere. The gas provides a relatively high electron drift velocity at a relatively low electric field strength. A pair of electrodes are spaced apart within the envelope and are connected to respective switch terminals for connecting to a load. The voltage gradient between the electrodes so spaced is insufficient at rated voltage to produce any substantial secondary ionization. The gas is ionized by a beam of high energy electrons introduced into the gas through the envelope. Means is provided for turning the beam on and off, thereby closing and opening the current path through the gas and effecting the switching of current through the load.