Abstract: A discharge tube adapted to produce a light by an extraneous high frequency electromagnetic field is heated before discharge to thereby improve the rising-up of the discharge and achieve uniformization of emitted light. Further, the discharge tube is heated by an electrode which applies a high frequency electromagnetic field to the discharge tube.

Abstract: An illumination apparatus includes a discharge tube for emitting light upon an application of an external high frequency wave electromagnetic field, an electrode, arranged outside the discharge tube, for applying the high frequency wave electromagnetic field to the discharge tube, a high frequency wave applying unit for supplying high frequency wave power to the electrode, and a projected portion extending from the discharge tube. The projected portion extends to a position where the high frequency wave electromagnetic field generated by the electrode has a level lower than a discharge initiation level. The high frequency wave power is controlled by changing a voltage, a frequency, a duty ratio or the like.

Abstract: A system and associated method for operating a gas discharge lamp so as to provide a positive voltage-current characteristic. An AC or DC source is used to provide electron heating, without in itself providing ionization, of the lamp gas. Superimposed on this signal is a pulsed source of power having an average output power substantially less than the AC or DC source power for providing ionization of the lamp gas.

Abstract: In a fluorescent lamp, a "soft" start-up circuit initially applies a lamp, or inter-electrode, voltage which is limited to a peak voltage that will not start the lamp prior to heating of the lamp cathode to the proper temperature. The lamp cathode is then heated to the proper start-up temperature after which the lamp voltage is increased to a value well in excess of the ignition voltage required for all lamp types and operating characteristics in initiating lamp operation. The increased lamp voltage is applied in a pulsed manner until the lamp is ignited, whereupon the lamp may be operated at normal lamp current and cathode voltages or the lamp filaments may even be turned off with a consequent savings in input power.

Abstract: A lighting method for vacuum fluorescent display which is lighted dynamically with frequency f.sub.1 includes applying a time-varying voltage with approximate frequency of (n+1/2)f.sub.1 to the cathode of the vacuum fluorescent display, where n is a predetermined natural number.By the method described, flickering in the display is suppressed even when, in the dynamical lighting of the vacuum fluorescent display, the cathode of the vacuum fluorescent display is heated with a time-varying voltage and the lighting duty ratio is reduced.

Abstract: A starting, hot restarting and operating circuit includes a pulse circuit for applying high voltage pulses to an HID lamp for starting or hot restarting. After a set interval of pulses if the lamp has not ignited, the pulse circuit is turned off for a selected inactive interval after which pulses are applied to the lamp again. If ignition does not occur after several active/inactive cycles, the circuit is deactivated until reset by turning the power off and on.

Abstract: A circuit system for igniting and lighting a high-pressure discharge lamp, particularly a sodium vapor lamp, comprising a pulse generator for generating signals of at least 1 kHz frequency being a high-frequency DC/AC converter connected to a direct current source and an ignition circuit coupled with the pulse generator including a high-pressure discharge lamp, a condenser connected in parallel to the high-pressure discharge lamp and an inductive member connected to the condenser and the high-pressure discharge lamp and forming a series member with the condenser the ignition circuit is provided with a transformer having a secondary winding connected in series with the inductive member for ensuring high reliability of igniting and for improving the conditions of lighting.

Abstract: According to the present invention, a portion of an applied commercial AC supply (60 Hz) is rectified, filtered and a controllable oscillator in a pulse width modulator chip serves as a signal generator which has both duty cycle and frequency control adjustments. An output signal is coupled via an impedance matching circuit to the input primary winding of a signal transformer having a pair of secondary windings which drive a pair of tandem connected electronic switches which, in turn, are connected across a second DC supply which has a high direct current voltage derived from the input AC line voltage (110-120 V AC 60 Hz).

Abstract: A circuit for operating a discharge lamp at a low frequency AC voltage while repetitively interrupting at a high frequency the voltage component to be applied to the lamp. The circuit includes at least one switching transistor for repetitively interrupting the voltage to be applied to the lamp at the high frequency, for example, 40 KHz so as to allow the use of a light and less bulky inductor as the current limiting conductor to be connected in series with the lamp. A bridge inverter is provided to have at least one pair of switching transistors for alternately reversing a DC voltage to apply the resulting AC voltage to the lamp at the low frequency, for example, 100 Hz low enough to stably operate the lamp without suffering from acoustic resonance. The high frequency component is bypassed through a bypass capacitor connected in parallel with the lamp.

Abstract: Subject track lighting system comprises a more-or-less regular lighting track having at least two pairs of track conductors. Of these track conductors, an initial pair carries the regular 120 Volt/60 Hz power line voltage. Plugged into the track and connecting with the initial pair of track conductors is one or more voltage-conditioning adapters--with each such adapter receiving its input voltage from the initial pair of track conductors and providing its conditioned output voltage to one of the other pairs of track conductors. Thus, depending upon the particular functions provided by the adapters, the different pairs of track conductors may be used in independently different ways. For instance, with one adapter being a frequency converter with an output voltage of 12 Volt/30 kHz, the pair of track conductors to which its output is connected may be used directly with low-voltage Halogen lamps--while ordinary 120 Volt incandescent lamps may simultaneously be used with the initial pair of track conductors.

Abstract: A relatively light-weight auxiliary power track is adapted to be plugged into and supported by a regular power track in an otherwise ordinary 120 Volt/60 Hz track lighting system. A compact frequency converter is operative to provide 120 Volt/30 kHz high-frequency voltage on the auxiliary track, and light-weight low-voltage Halogen lighting units are provided for plug-in use therein. Each of these lighting units comprises a high-frequency light-weight voltage step-down transformer.

Abstract: A high pressure discharge lamp in which discharge between a pair of main electrodes in an arc tube of the discharge lamp is sustained by a D.C. or high frequency current. The circuit comprises discharge mode controller for controlling the discharge such that mainly a low-frequency discharge is produced between the main electrodes at least within a predetermined time from initiation of the discharge within the arc tube, and subsequently transferred to the D.C. or high-frequency discharge.

Abstract: In a discharge lamp lighting system comprising a DC or low frequency (LF) AC main source and a high frequency (HF) source, a high frequency component from the HF source and low frequency component from the main source are supplied in an overlapping manner to the discharge lamp. The HF source of the lighting device is energized by input current from the main source for producing a high frequency current. In addition, the lighting device for the discharge lamp include in combination an HF blocking circuit, an HF passing circuit and/or a matching circuit for the HF source to supply effectively a high frequency component to the discharge lamp, as well as a low frequency component from the main source.

Abstract: A flashlamp system is described which permits the use of flashlamp tubes of increased diameter for higher average power capability while retaining the desirable characteristics of a small diameter, wall stabilized tube which includes small image size, short pulse duration and high ionization level. A series of low level pre-pulses are applied to the flashlamp prior to a main pulse to form a low density region along the flashlamp discharge axis for the main pulse for generating radially directed acoustic waves, thereby to confine the main discharge to a small low density region near the tube center. When Xenon flashlamps are used, this results in a higher ionization level of the molecules along the axis of the flashlamp which increases the ratio of the short-lived XeII emission to long-lived continuum, thereby effectively reducing pulse duration.

Abstract: An apparatus for a gaseous discharge lamp includes a power controlling device for converting an AC voltage into a phase control output, a high frequency generating device for converting the output of the high frequency generating device into an high frequency output and a discharge lamp which is lighted by the output of the high frequency generating device and whose filament is heated. The high frequency generating device includes a DC power source for supplying a DC voltage to the power controlling device whenever the power controlling device remains to generate the phase control output. The output of the DC power source heats the filament of the discharge lamp for a period during which no phase control output is produced.

Abstract: A disco light assembly is provided which includes a multiplicity of individual electric lamps formed in a circle, or in any other appropriate configuration, and which are illuminated in any desired sequence in response to a disco beat. The individual lamps are preferably of the high intensity type, and each generates a shaft of light, preferably white, when illuminated. A common regulated power supply is provided which supplies a continuous filament current to all the lamps which is of sufficient amplitude to maintain the filaments in a warm state but insufficient to illuminate the lamps. Each lamp has its own control module connected to the common power supply, and when a module is triggered, it causes a high current pulse to be introduced to the corresponding lamp for a few milliseconds, followed by a power current of sufficient intensity to illuminate the lamp. The power current continues for so long as the lamp is to be illuminated.

Abstract: A low frequency AC voltage is rectified through a full-wave rectifier to obtain a pulsating voltage, which is superimposed with an auxiliary voltage of a predetermined level provided from an auxiliary power source, and the resultant composite pulsating voltage is inverted at an inverter to a high frequency voltage. The high frequency voltage thus obtained from the inverter is used to operate a discharge lamp. Minimum value V.sub.min of the resultant voltage is set to be 1/3 to 4/5 of the maximum value V.sub.max of the resultant voltage.

Abstract: A high pressure discharge lamp apparatus comprises:a discharge tube and a current limiting device such as a choke coil connected in series for connection across an A.C. power source, anda pulse generator connected by its output terminal in parallel to the discharge tube,the apparatus is characterized in that:said pulse generator impresses reignition pulses on said discharge tube at least during a period defined as from a zero-cross point of the source voltage of the power source to a phase defined by a peak of reignition voltage of lamp voltage waveform when no reignition pulse is impressed on the discharge tube, thereby retaining lamp current of the discharge tube without forming zero-current period,thereby the lamp is stably lit with such a high lamp voltage as is almost equal to the power source voltage and the power of reignition pulse can be saved without harming stability of lighting. Thus a stable lighting of the high pressure discharge lamp with a a high power efficiency becomes possible.

Abstract: A discharge lamp lighting circuit system comprises a discharge lamp, an intermittent oscillation circuit, and an arrangement for controlling the energy supplied for lighting the discharge lamp with a high power factor. The intermittent oscillation circuit is energized by a low frequency a.c. power supply, i.e. a commercial alternating current power supply, for intermittently generating a high frequency high voltage in each half cycle of the alternating current of the low frequency a.c. power supply. By supplying the low frequency alternating current voltage and the intermittent high frequency high voltage to the lamp the discharge lamp is reignited in each half cycle of the a.c. of the low frequency alternating current power supply and the lit state of the discharge lamp is sustained by the low frequency alternating current voltage.

Abstract: A method of operating a high intensity discharge lamp having a pair of electrodes hermetically sealed within an arc tube, the method comprising frequency modulation of a carrier waveform in the kilohertz range to provide a variable frequency AC output, and applying the AC output across the electrodes of the lamp to thereby operate the lamp in a manner which minimizes or avoids acoustic resonance effects within the arc tube. The circuit includes an inverter having a first input provided by a DC power source and a drive input coupled to a square wave carrier generator which is frequency modulated by a ramp generator. The resulting variable frequency AC output of the inverter is then coupled across the lamp electrodes.

Abstract: This application discloses circuits for use with arc discharge devices wherein a D.C. or A.C. high frequency, high voltage source is provided in conjunction with either a low frequency or D.C. voltage source. The high frequency, high voltage circuit is a low power circuit providing sufficient voltage to ionize the arc. If desired the low power circuit may also control the major arc power obtained from the low frequency or D.C. source which does not require a ballast. By virtue of this arrangement much smaller, lighter and lower cost circuits than conventional ballast circuits can be used.

Abstract: There is disclosed an emergency lighting system which is capable of distinguishing between a loss of power due to the opening of a line switch, and a loss of power resulting from a line failure when the switch is closed. A secondary power source powers the light in the event of a line failure. Thus when the line switch is open, i.e., when emergency lighting is not necessary, the light is not powered by the secondary source.

Abstract: An inductive-capacitive charge-discharge ignition system includes an ignition transformer primary winding and a capacitor to be charged by a unipolar alternating current source. An electronic switch connects the primary winding and capacitor in parallel during the discharge mode of the system so that the discharge current from the capacitor aids the discharge current in the primary winding. Rectifiers may be used between the outputs of the source and the primary winding and capacitor. Another version of this system employs DC power to charge the primary winding, and the unipolar source to charge the capacitor, with a rectifier between the source and capacitor. Another capacitor may be used in the secondary winding of the ignition transformer. The system may be controlled by a variety of timers. A high velocity igniter arc having luminous particles surrounding a more concentrated filament of such luminous particles is developed by the system extending across the entire base of an igniter.

Abstract: An arrangement for starting and operating a low-pressure mercury vapor discharge lamp provided with preheatable electrodes. The lamp is supplied from a battery via two direct-to-alternating current converters connected between the battery and the lamp. One converter is a voltage-controlled converter which exclusively effects the preheating of the electrodes, whereas the other converter supplies the lamp current only. This arrangement provides reliable ignition and operation of the lamp even in the case of a large variation in the battery voltage.

Abstract: An energizing circuit for gas discharge lamps for room or street lighting or for lights used in document copying machines and the like comprises means for continuously energizing the same at a low non-useful light producing level when such lamps are not needed by a voltage which strikes an arc and maintains a low level of ionization with an infinitesimally small current and very little energy drain. This voltage may be an AC voltage or a DC voltage supplied by a unique circuit including a number of DC voltage sources, rectifiers, voltage adjusting and current-limiting impedances and electronic switches. The lamps are energized by AC or pulsating DC supplied by the aforesaid or other electronic switches operated at a high frequency of at least about 20-30 kilo-Hertz.

Abstract: An anode and a cathode are disposed in an opposing relation in a tubing in which an inactive gas is enclosed to form a discharge lamp by which an atomic spectrum is emitted. The cathode contains atomic spectrum emitting elements also serving to form the material of cathode. The discharge lamp is supplied with a high frequency power from a high frequency source and simultaneously with a direct current power from a direct current source. This causes the direct current discharge and high frequency discharge to be effected between a pair of electrodes in a superimposed manner. The atoms sputtered by the direct current are efficiently excited by the application of the high frequency with the result that atomic spectra with high brightness are obtained.

Abstract: To prevent high-intensity-discharge (HID) lamps from extinguishing for prolonged periods due to a power interruption or an appreciable drop in line voltage, a rectifier-battery combination provides standby power for operating a high-frequency inverter. The output of the inverter connects to the HID lamps through impedance means which passes a greatly reduced high-frequency current as compared to the normal lamp operating current, in order to sustain the operation of the lamps at a very reduced power level. Upon restoration of the normal line voltage, the lamps again operate with normal power consumption. The same wiring can be used for both the normal lamp operating current and the high-frequency sustaining current or separate wiring systems can be used if desired. The high-frequency current can be supplied simultaneously with the normal operating current or the high-frequency current can be supplied only during periods of power interruption.

Abstract: Color rendition of high pressure sodium vapor discharge lamps is improved by disclosed operating circuit for applying pulsed direct current to the lamp. The circuit includes a direct current ballast circuit having a low ripple factor, a filter capacitor charged by the output of the ballast circuit, and a pulsing circuit comprising a transistor switch which operates to apply DC pulses on the lamp at a predetermined repetition rate and duty cycle to provide desired color properties of the lamp.

Abstract: Electrical ballast circuit for operating gaseous discharge lamps with direct current. An inductive reactor coil connected to an alternating current source is connected to a discharge lamp via a full-wave rectifier, and an auxiliary induction coil inductively coupled to the reactor coil is connected to the discharge lamp via another full-wave rectifier, resulting in the currents from the respective rectifiers to the lamp being out of phase with one another, thereby raising the average current through the lamp and the voltage across the lamp to prevent lamp de-ionization and reduce lamp re-ignition voltage. Series connected capacitors may be incorporated in the circuit to increase the starting voltage on the lamp if necessary.

Abstract: A lighting system for gaseous-discharge lamps for applying high voltage pulses to ignite the lamp and for discontinuing the application of high voltage pulses when the lamp is operating. The system includes ballast facilities having an inductive portion, and a control circuit which is responsive to a voltage induced in the inductive portion when the gaseous-discharge lamp operates. When the control circuit is operative, the pulsing portion of the system is disabled. The system is arranged so that the components of the control and pulsing circuits are not subjected to the application of high voltage pulses at any time.

Abstract: A disco light assembly is provided which includes a multiplicity of individual electric lamps formed in a circle, or in any other appropriate configuration, and which are illuminated in any desired sequence in response to a disco beat. The individual lamps are preferably of the high intensity type, and each generates a shaft of light, preferably white, when illuminated. A common regulated power supply is provided which supplies a continuous filament current to all the lamps which is of sufficient amplitude to maintain the filaments in a warm state but insufficient to illuminate the lamps. Each lamp has its own control module connected to the common power supply, and when a module is triggered, it causes a high current pulse to be introduced to the corresponding lamp for a few milliseconds, followed by a power current of sufficient intensity to illuminate the lamp. The power current continues for so long as the lamp is to be illuminated.