Abstract: A power supply control circuit includes: a conducting part configured to be controllable in its a conducting amount for conducting a power supply current to a load circuit; a current change ratio detecting part detecting a change rate of the power supply current supplied to the load circuit; and a control part controlling the conducting amount of the conducting part according to the change rate of the power supply current detected by the current change detecting part, wherein: the control part carries out feedback control of reducing an increasing rate of the conducting part as the power supply current change rate is larger.

Abstract: A LED lighting system (100) employing a LED light source (115), a user interface (124, 128, 134, 138), and a controller (112). The LED light source (115) includes a plurality of colored LEDs emitting one of a plurality of spectral outputs as a function of one or more currents flowing through the colored LEDs, where each current has a variable time average flow. The user interface (124, 128, 134, 138) facilitate a user selection of one of the spectral outputs. The controller (112) controls the variable time average flow of each current flowing through the colored LEDs as a function of the spectral output selected by the user.

Abstract: A portable terminal, which has an antenna disposed within a housing accommodating a circuit board, capable of securing a clearance between the antenna and parts of the circuit board, etc. within the housing without increasing the size of the housing, whereby the antenna performance can be prevented from degrading when transmitting or receiving, in which the antenna is insert-molded integrally with the housing accommodating the circuit board within it.

Abstract: A backlight device includes a light source module having a plurality of light sources, a detecting circuit, a control unit, and a pulse width modulation (PWM) driving circuit. The detecting circuit is used for detecting the brightness of the light source module and generating a detecting signal to the control unit, such that the control unit outputs a control signal according to the detecting signal. In addition, the PWM driving circuit is used for generating a PWM signal for driving the light source module. In the present invention, the PWM driving circuit adjusts the base frequency of the PWM signal according to the control signal without adjusting the duty cycle of the PWM signal, so as to control the brightness of the light sources.

Abstract: A monopole or dipole antenna includes a radiating element having at least one notch. The at least one notch intersects at least at one point on an edge of the radiating element wherein the intersecting point is located at a distance to a feeding point. The distance being shorter than half a length of a longest edge of the radiating element. A maximum width of the at least one notch is narrower than a half of a longest length of the at least one notch.

Abstract: A ballast for an electrodeless discharge lamp includes a high frequency power supply that supplies a high frequency electric power to an induction coil for operating the lamp. A dimmer controller generates a control signal in response to a dimmer command designating a varying dimming ratio. The control signal defines a first period Ton in which the power supply is controlled to apply a coil voltage of a first level V1 to the induction coil for operating the lamp. The first period is followed by a second period Toff in which the power supply is controlled to apply the coil voltage of a second level V2 that is lower than the first level and fails to sustain the lamp. The control signal defines, between the second period and the first period, a starting period Tst in which the coil voltage increases continuously for smooth transition from an off-condition to an on-condition of the lamp.

Abstract: Apparatus and methods are disclosed for measuring cathode fall within a fluorescent lamp that contains an electrode and a gas. A level of cathode fall associated with the electrode may be identified based on an intensity and wavelength of radiation emitted by the gas.

Abstract: A halogen lamp includes a mains base and a converter operably connected to the mains base. The converter has a lamp socket, a toroid transformer, and a heat sink disposed within a center opening of the toroid transformer. A lamp is removably disposed in the lamp socket. The converter has a power density between 0.75 and 3.75 Watts/cm3. In an alternate embodiment, the halogen lamp includes a low voltage, low pressure IRC lamp operably connected to the converter.

Abstract: An electron emission device and an electron emission display, in which a driving electrode is protected from being damaged when an overcurrent instantly flows therein. The electron emission device includes a first driving electrode disposed on a plate, a second driving electrode disposed on the plate and insulated from the first driving electrode, and an electron emission portion connected to the first driving electrode. The electron emission portion emits electrons in response to a voltage difference between the first driving electrode and the second driving electrode. The second driving electrode has at least two separate portions, and the at least two separate portions are coupled to each other by at least one band having a predetermined width adapted to electrically isolate at least one portion of the second driving electrode from the electron emission portion when an overcurrent is applied between the second driving electrode and the electron emission portion.

Abstract: An external electronic control type electrodeless lamp includes a lighting device. The lighting device includes a body having at least a first conductive plate and a second conductive plate. Each conductive plate is electrically connected to an electronic control system external to the lighting device. The body has a plurality of even-numbered sides. The number of the sides of the body is at least four. The conductive plates are mounted on at least two opposite sides of the body. The electronic control system includes a magnetic core that, when energized, creates a magnetic field, and current generated due to change in the magnetic field is supplied to the conductive plates to light the lighting device.

Abstract: In a discharge lamp lighting apparatus, in a transient period from the time a discharge lamp is lit in a cold state to the time the discharge lamp reaches a static lighting state, the power applied to the discharge lamp is reduced over time after an initial maximum power that exceeds the rated power. A maximum power regulator circuit is provided to regulate the applied power in the transient period such that the applied power does not exceed an upper limit power line M1 or M2 that is reduced over time after the application of the initial maximum power. In this way, the application of excessive transient power is prevented from continuing longer than necessary in the event of a failure in a load, thus limiting the amount of generated heat and preventing thermal destruction.

Abstract: A ballast having a dimming device for a low-pressure discharge lamp. It has two technically different possibilities for controlling the lamp brightness. The first possibility for controlling the lamp brightness is by means of adjusting the amplitude of the lamp current. The second possibility for brightness control is based on the fact that the low-pressure discharge lamp can be operated with a pulsed lamp current. In particular, both operating modes are used in combination in specific brightness ranges.

Abstract: A ballast having a dimming device for a low-pressure discharge lamp. For brightness control, the DC component of the periodically modulated envelope of the lamp current is varied. In this case, the current does not fall below predetermined minimum values for the lamp current. Phases with a high lamp current are characterized by a steep rising edge, compared with a flatter falling edge.

Abstract: A light-emitting element driving apparatus includes a constant-current circuit and a control circuit. The constant-current circuit includes a plurality of constant-current sources that are connected in parallel with each other and are respectively connected in series to a light-emitting element to supply current to the light-emitting element. The constant-current sources arrange 1st to Nth (N is an integer not smaller than 2) constant-current blocks each including 1st to Mth (M is an integer not smaller than 2) constant-current sources. A current ratio among the 1st to Mth constant-current sources is substantially identical in all of the constant-current blocks.

Abstract: A rechargeable portable light having a housing member with an opening for the emission of light, and two possible charging systems including an AC charger, and an auto or boat charger. An electronic circuit is located within the housing member and includes at least one super capacitor for power storage. The super capacitor is charged by a charging system. A charging system is presented that can charge two super capacitors in series, or more than two super capacitors in series. A power inverter circuit with a high efficiency (approximately 90% to 95% efficiency) is used to regulate voltage and current from one super capacitor or two or more super capacitors in series to a light emitting diode. This circuit includes at least one light emitting diode (LED) positioned near the opening in the housing member, and a switch interposed between the capacitor and the output circuit. The switch is closed when power is delivered from the super capacitor to the LED.

Abstract: A power conversion circuit improves lamp operating life and lamp efficiency by driving a fluorescent lamp with a square wave signal. The square wave signal is an alternating current signal with relatively fast transition times. The square wave signal advantageously reduces lamp current crest factor for more efficient operation of the fluorescent lamp.

Abstract: A balanced current lamp module driven by a power source includes a first balanced current unit, a second balanced current unit and a balanced transformer. The first balanced current unit includes a first transformer, a first lamp and a second lamp. The first transformer has one coil electrically connected with the power source, and the other coil having two ends respectively electrically connected with the first lamp and the second lamp. The second balanced current unit includes a second transformer, a third lamp and a fourth lamp. The second transformer has one coil electrically connected with the power source, and the other coil having two ends respectively electrically connected with the third lamp and the fourth lamp. The balanced transformer has one coil electrically connected with the first lamp, and the other coil electrically connected with the fourth lamp.

Abstract: A high frequency ballast power supply for a high intensity discharge lamp includes a variable frequency voltage generating circuit for producing a regulated cyclical voltage. After ignition of the lamp, the variable frequency voltage generating circuit operates to vary the frequency of the cyclical voltage over the range of frequencies with a maximum frequency of less than or equal to about 375 kHz. A resonant circuit for regulating the power supplied to the lamp is interposed between the variable frequency voltage generating circuit and the lamp.

Abstract: A power controller converts a line voltage to an RMS load voltage for a lamp, and includes a switch and a microcontroller that operates the switch to define the RMS load voltage. The microcontroller senses a load voltage of the lamp, compares the sensed load voltage to a reference RMS voltage, and operates the switch in response to the comparison so that the RMS load voltage is substantially constant at the reference RMS voltage over an operating range of the line voltage and so that the RMS load voltage decreases with decreasing line voltage at line voltages less than the operating range. The operating range of the line voltage is defined to have a minimum that is a non-zero line voltage at which a load current is a predetermined maximum. The voltage conversion circuit may be a phase clipping circuit or a pulse width modulation circuit.

Abstract: A method for controlling an inverter under altering voltage aims to change the electric conductive interval of the electric conductive cycle of the inverter corresponding to alteration of an input voltage so that the dimming duty cycle, electric conductive cycle and transformer oscillation duty cycle of the inverter can be maintained at a selected level. Thereby when the input voltage is altered, the existing dimming range can be maintained and actuation electricity output is stabilized. The transformer can be protected and the life span of the load can be extended.