Abstract: Perceived output color and intensity (brightness) of light from a three-element red-green-blue (RGB) light emitting diode (LED) or optical combination of three LEDs (red, green and blue) are controlled with three pulse train signals, each having fixed pulse width and voltage amplitude and then increasing or decreasing the frequency (increasing or decreasing the number of pulses over a time period) of these pulse train signals so as to vary the average current through each of the RGB-LEDs. This reduces the level of electro-magnetic interference (EMI) at any one frequency by varying the pulse train energy spectrum over a plurality of frequencies.

Abstract: An AC light emitting device is disclosed. The AC light emitting device includes at least four substrates. Serial arrays each of which has a plurality of light emitting cells connected in series are positioned on the substrates, respectively. Meanwhile, first connector means electrically connect the serial arrays formed on respective different substrates. At least two array groups each of which has at least two of the serial arrays connected in series by the first connector means are formed. The at least two array groups are connected in reverse parallel to operate. Accordingly, there is provided an AC light emitting device capable of being driven under an AC power source.

Abstract: To a constant-current power supply whose output current can be variably set, light emitting modules can be connected in parallel. A control unit recognizes connection information outputted from an information output unit provided in each of the light emitting modules and varies the output current of the constant-current power supply. Drive can be controlled in response to a state of the connected light emitting modules such as the connecting number of light emitting modules.

Abstract: An electronic driver apparatus and methods are disclosed for driving power an organic LED or other large area solid state light source, in which a switch mode DC current source provides DC current to drive the light source according to a control input and a controller provides a ramped pulse modulated control input to the current source for at least some values of a dimming setpoint signal or value to mitigate damaging current spikes by controlling di/dt of the drive current.

Abstract: A ballast circuit adapted for converting an input alternating current (AC) mains power received at input terminals to an output alternating current (AC) to supply a load, e.g. a gas discharge lamp. The output terminals of the ballast connect to the load in parallel with another ballast circuit. The ballast circuit is configured to supply the output AC current to the load in parallel with an AC current output of the other ballast circuit. A synchronization module attached at the output is adapted for synchronizing the output alternating current (AC) of the ballast circuit with the AC current output of the other ballast circuit. The synchronization module is configured to synchronize phase of the output alternating current with phase of the AC current output of the other ballast circuit.

Abstract: A PWM architecture of a microcontroller is disclosed that includes a fault module for regulating and detecting faults in current sensing or illuminating devices (e.g., LED strings). The fault module is part of a hardware regulation loop of LED voltage and LED current that allows the CPU to be placed in idle mode (“IDLE”) while an LED string is regulated in illumination. The microcontroller includes a PWM generator having a double channels PWM timer with a specific fault mode and an amplified comparator with a voltage reference. The architecture allows tuning of various parameters, including LED peak current, LED voltage supply, LED voltage regulation step and LED dimming value. In IDLE mode, the hardware regulation loop can regulate LED peak current and LED voltage supply without any CPU resource (microcontroller in IDLE mode). The fault module part of the hardware regulation loop can also detect and inform the CPU of: 1) an open LED; 2) a weak battery; and 3) an LED voltage that is under a target value.

Abstract: A clock generation circuit that can reliably recover from a state in which generation of a clock is stopped even during a power-on process and a normal operation. The clock generation circuit includes a clock extraction circuit that extracts an extracted clock from an embedded signal on which a clock and data are superimposed, and a stop detection circuit that detects a stop of the extracted clock on the basis of the embedded signal and the extracted clock and outputs a reset signal that resets the clock extraction circuit to an initial state.

Abstract: A system is for a landing site for a helicopter or a load suspended from a helicopter, where landing positioning references are visualised as a luminous pattern on the landing site, and where the landing positioning references are formed as lines of light projected on the landing site from one or more light sources arranged at the landing site. A method is for forming of landing positioning references visualised as a luminous pattern on the landing site.

Abstract: Supplying pulsed current to a load involves repeatedly driving an electrical load between successive active and idle states via a regulator that includes a switched mode power supply. The regulator receives input current from a direct current power source and provides output current to at least an energy storage device in the idle states of the electrical load. The energy storage device is coupled to the load and the regulator. Output current is provided from both the regulator and the energy storage device to the electrical load in the active states of the electrical load. A storage capacity of the energy storage device is selected so that a duty cycle of the input current is greater than a duty cycle of the output current.

Abstract: An alternating current (AC) light-emitting device includes a waveform generating unit and an AC light-emitting unit. The waveform generating unit is configured to receive an AC electrical signal and to generate a drive signal by adjusting one of: voltage amplitude of the AC electrical signal during one of positive and negative half-cycles of the AC electrical signal, and waveform level of the AC electrical signal. The AC light-emitting unit includes a first light-emitting component and a second light-emitting component, and the second light-emitting component emits a different wavelength light compared to that emitted by the first light-emitting component. The first and second light-emitting components are electrically coupled to the waveform generating unit to receive the drive signal, and emit light according to the drive signal.

Abstract: A light-emitting adjustment method and a display device are provided. The display device includes a voltage source, a light-emitting diode array, a pulse width modulator, a current sensor and a light-emitting adjuster. The voltage source provides an operating voltage. The pulse width modulator provides operating pulse signals to multiple light-emitting diodes arranged in column in order. The current sensor senses a plurality of overall current values of the light-emitting diodes at different timings during the light-emitting diodes are sequentially enabled. The light-emitting adjuster computes an operating current value of each of the light-emitting diodes according to the overall current values and performs a compensation operation based on the operating current value to obtain and output a compensation signal.

Abstract: An LED drive circuit that is connectable to an a.c. power supply via a phase control type light adjuster and drives an LED load, including a discharge portion that consumes energy of a resonance phenomenon generated by a light adjuster capacitance component of the phase control type light adjuster and a light adjuster inductance component of the phase control type light adjuster when a current holding portion of the phase control type light adjuster is turned on.

Abstract: A device and a method for driving a light-emitting diode include using multiple current guiding control circuits to drive multiple LED modules. Each of the current guiding control circuits includes at least two transistors connected in parallel to constitute at least two switch circuits. Each of the current guiding control circuits permits or prevents electric current to flow to an immediate downstream one of the LED modules in response to a predetermined voltage level of the positive part of a voltage source. The respective the current guiding control circuits are responsive to different voltage levels. As a result, a maximum number of LED modules are driven to emit light at a given voltage level, thereby achieving the purposes of efficiently utilizing electric power and reducing power loss.

Abstract: A constant temperature LED driver circuit for controlling the rate of lumen depreciation and therefore useful lifetime of an LED array by keeping the LEDs at a fixed temperature. A temperature sensing means, which measures the temperature of the LEDs, is coupled to a variable power source that drives the LED array. The current provided to the LED array is adjusted in response to the temperature sensing means to ensure that the LEDs remain at a constant temperature regardless of changes in ambient temperature.

Abstract: The present invention relates to a light emitting device. The light emitting device according to the present invention comprises a light emitting cell block having a plurality of light emitting cells; and a bridge rectifying circuit connected to input and output terminals of the light emitting cell block, wherein the bridge rectifying circuit includes a plurality of diodes between nodes. In manufacturing an AC light emitting device with a bridge rectifying circuit built therein, the present invention can provide a light emitting device capable of enhancing the reliability and luminance of the light emitting device by setting the size of diodes of the bridge rectifying circuit to be a certain size and controlling the number thereof.

Abstract: An AC-driven LED assembly with discretely packaged LEDs being connected in an AC circuit and being sized preferably substantially 2.5 mm or less in length and width, and more preferably 2.0 mm or less; and being mounted to a substrate at a distance from the other of preferably approximately 3 mm or less, and more preferably 2.0 mm or less.

Abstract: A constant voltage dimmable LED (Light Emitting Diode) driver is disclosed that is compatible with all types of dimmers, including conventional phase cut (TRIAC) dimmers, and behaves like a conventional constant voltage driver which can be connected to any size of LED load that has a matching voltage rating. The driver produces a continuous train of pulses for driving the LED load and obtains an averaged measure of the voltage at the AC input for controlling the duty cycle of the continuous train of pulses. Therefore, when the averaged measure of the voltage at the AC input is reduced by a dimmer, the duty cycle reduces, resulting in a dimmed LED. The driver can be created by adding a few components to a conventional wide input range AC-DC converter without or with very little modifications.

Abstract: An LED package containing integrated circuitry for matching a power source voltage to the LED operating voltage, LEDs containing such integrated circuitry, systems containing such packages, and methods for matching the source and operating voltages are described. The integrated circuitry typically contains a power converter and a constant current circuit. The LED package may also contain other active or passive components such as pin-outs for integrated or external components, a transformer and rectifier, or a rectifier circuit. External components can include control systems for regulating the LED current level or the properties of light emitted by the LED. Integrating the power supply and current control components into the LED can provide for fabrication of relatively small LEDs using fewer and less device-specific components.

Abstract: An integrated Light Emitting Diode (LED) device including multiple LEDs connected to a circuit board, integrated circuit (IC) drivers connected to the circuit board, and a first alternating current (AC) terminal and a second AC terminal connected to the circuit board.

Abstract: A modular electronic ballast is provided for powering a fluorescent lamp. A motherboard is configured to receive an AC input signal, one or more supplemental input signals and a feedback signal from the lamp. A ballast control circuit generates an output signal for an oscillating inverter driving the lamps. A daughter card is coupled to the motherboard and selected from a plurality of daughter cards, each configured to provide a dimming control signal having predetermined characteristics and readable by the control circuit. The daughter cards are collectively configured to provide dimming control signals in response to each of a line-coupled demand response interface, one or more digitally addressable interfaces, analog dimming signals received via said supplemental communications bus, and three-wire phase control signals received via said AC line and said supplemental communications bus. The motherboard is configured to interchangeably receive any one of the daughter cards.

Abstract: An LED device for use with an AC voltage power source configured such that at least one LED emits light during a positive phase of power provided from an AC power supply and at least one LED emits light during the negative phase of power provided from an AC power supply. The LED device includes a first power connection lead and a second power connection lead, both leads capable of being connected to and receiving power from an AC power supply.

Abstract: The invention relates to an LED lamp for warm white light having an LED module consisting of at least one colour-converted blue or UV LED, and at least one monochromatic LED, preferably a red LED, in the case of which the mixed spectrum produces white light with a colour temperature CCT of between 1500K and 2400K, preferably 1700K and 2100K at room temperature, and between 1800K and 2400K, preferably 2100K and 2300K at a stationary operating temperature of, for example, between 70° C. and 80° C. of the LED lamp.

Abstract: Cehlorosilicate-based phosphors configured to emit yellow-green light in a wavelength ranging from about 500 nm to about 560 nm in response to an excitation source emitting at about 400 nm to about 480 nm, wherein the light emitted by the phosphor has a decay time ranging from about 1 millisecond (1 ms) to about 10 milliseconds (10 ms). The phosphor comprises a compound of the family Ca8-x-yAxEuyMg1-m-nBmMnn(Si1-sCsO4)4R2, where A is at least one divalent cation including Ca, Sr, Ba; B is Zn or Cd, or a divalent metal ion other than an alkaline earth; C is a cation, including at least one of Ge, Al, B, Gd, Ga, and N, and R is an anion, including F, Cl, Br, I, all respectively either individually, or in combinations.

Abstract: A backlight unit and a liquid crystal display using the same are provided. The backlight unit includes a plurality of lamps, each including first and second electrodes, first and second substrates, a bottom case for receiving the substrates and lamps, first and second inverter units, and first and second wires. First and second common electrode patterns are formed on the first and second substrates and are commonly connected to the first and second electrodes, respectively. The first and second inverter units are disposed on a rear surface of the bottom case at positions corresponding to the first and second substrates, respectively. The first wire connects the first common electrode pattern and the first inverter unit via holes in the first substrate and the bottom case. The second wire connects the second common electrode pattern and the second inverter unit via holes in the second substrate and the bottom case.

Abstract: The present invention discloses an LED controller with phase-shift dimming function and an LED Phase-Shift dimming circuit and method thereof. The LED controller includes: a power circuit for supplying DC power to multiple LED channels; and an LED phase-shift dimming circuit for receiving a pulse width modulation (PWM) input signal and generating multiple phase-shifted PWM signals with a shifted phase between one another, wherein a turn-ON timing of each of the multiple phase-shifted PWM signals follows a turn-OFF timing of a previous PWM signal which is the input PWM signal or a previous one of the multiple phase-shifted PWM signals.

Abstract: The present disclosure discloses a lighting apparatus using a PN junction light-emitting element, the apparatus including: a power transmitting substrate having a plurality of boundaries defined thereon; a plurality of PN junction light-emitting elements positioned within each boundary and divided into a plurality of groups; and a first switch provided on the power transmitting substrate, wherein the first switch goes into the ON state by a supplied AC having a first voltage to cause PN junction light-emitting elements of a first group positioned within each boundary to emit light, and the first switch is in the OFF state when PN junction light-emitting elements of a second group, which is positioned within each boundary and connected in series to the first group, emit light by a supplied AC having a second voltage higher than the first voltage.

Abstract: An LED current PWM dimming module comprising: an input voltage regulator for regulating the constant direct current supplied by the LED driver power supply in order to maintain a fixed and stable supply voltage source to a timer-oscillator and a DC-DC buck converter; the timer-oscillator for generating a repetitive square wave electrical output to be fed to the DC-DC buck converter; and the DC-DC buck converter for producing a driving pulse-width-modulated (PWM) current output to power one or more LEDs from the repetitive square wave electrical output; wherein the timer-oscillator receives a control signal from an external dimming controller and adjusts the repetitive square wave electrical output frequency and duty cycle accordingly; and wherein the driving PWM current output frequency and duty cycle being varied in an open-loop manner.

Abstract: A lighting system for wirelessly providing power to a lighting assembly across a wall. The lighting system may be used, for example, for powering the lighting assembly positioned on an outside portion of the wall, such as on the outside of a boat hull. An example of the lighting system includes a power transmitter with a multi-frequency generator connected to a power source and a controller. The multi-frequency generator is configured to generate an oscillating signal at a predetermined frequency according to a control signal received from the controller. The power transmitter includes a transmitting coil connected to receive the oscillating signal. A receiving coil is positioned to form an inductive coupling with the transmitting coil. A plurality of conditioning units are connected to the receiving coil to receive the oscillating signal. The plurality of conditioning units are connected to provide power to a corresponding light or set of lights.

Abstract: A ballast (10) for powering one or two gas discharge lamps (30,40) includes an inverter (100), an output circuit (200), and a control circuit (500). During a period prior to startup of inverter (100), control circuit (500) monitors a signal within output circuit (200) in order to determine the presence of lamps with intact filaments that are present at the ballast output connections (202,204, . . . ,210,212). Preferably, control circuit (500) is realized by a programmable microcontroller which implements a dual timing scheme in order to accurately determine the number of lamps with both filaments intact. The resulting determination may be used for various purposes, such providing appropriate levels of filament heating and/or for setting thresholds for accurately detecting and protecting against various lamp fault conditions.

Abstract: A two level lighting ballast is provided, which includes a self-oscillating inverter circuit and a control circuit. The inverter includes an input; an output to selectively provide current to energize a lamp; a switching circuit operating at a switching frequency; a feedback transformer; and an impedance component. The feedback transformer is connected to the output, and drives the switching circuit based on the lamp current. The impedance component is connected in parallel with the feedback transformer, and is operated by the control circuit. When the control circuit enables the impedance component, the switching circuit operates in a first frequency range, and a first lamp current is provided. When the control circuit disables the impedance component, the switching circuit operates in a second frequency range, and a second lamp current is provided. The first frequency range is lower than the second, and the first lamp current is greater than the second.

Abstract: A method of arranging light emitting diodes (LEDs) is disclosed. The method includes M virtual lateral lines and N virtual vertical lines, which form virtual intersection nodes at the intersections; disposing N-1 lateral LEDs in each virtual lateral line with one lateral LED placed between two adjacent virtual intersection nodes, connecting the positive terminal of one later LED to the positive terminal of one of the two adjacent lateral LEDs, and connecting the negative terminal of the one lateral LED to the negative terminal of the other adjacent lateral LED; disposing M-1 vertical LEDs in each virtual vertical line except for the first and last virtual vertical lines, connecting the positive and negative terminal of one vertical LED in the same way; and connecting the AC power to the first and last virtual vertical lines.

Abstract: Methods and apparatuses for starting a discharge lamp are disclosed. In some embodiments, a lamp has an outer envelope connected at one end to a base and enclosing multiple double-ended arc tubes. Each arc tube is electrically connected at one end to an electrical lead positioned proximate the base of the lamp and at the other end to an electrical lead positioned proximate the distal end of the envelope. A voltage pulse is applied to the electrical lead positioned proximate the distal end of the envelope. Random starting of the arc tubes may thus be effected so that each arc tube is about equally likely to start, promoting uniformity of arc tube usage and long lamp life. Multiple arc tubes may be bulbous and staggered in axial displacement for space efficiency, and a diffusing shroud may improve optical characteristics. A heat barrier may facilitate fast restrikes.

Abstract: The present invention is directed to method, system and computer-readable media for controlling lighting devices. In some embodiments, a method for controlling pulse width modulated lighting devices within a lighting apparatus comprising a plurality of sets of lighting devices is disclosed. The method includes setting a counter for a first set of the plurality of sets of lighting devices using a master counter and an activation duration for one or more other sets of the plurality of sets of lighting devices. The method further includes determining an activation time period within a duty cycle for the first set of lighting devices using the counter for the first set of lighting devices and an activation duration for the first set of lighting devices. In some embodiments of the present invention, the lighting devices are light emitting diodes grouped into sets (or banks) and controlled to limit the magnitude and/or quantity of instantaneous current fluctuations in a power supply within the lighting apparatus.

Abstract: A light output device comprises a substrate arrangement with a plurality of light source device arrangements integrated into the structure of the substrate arrangement. The plurality of light source device arrangements comprise at least first and second light source devices (4a,4b) which are arranged in anti-parallel. This arrangement mounts at least two light source devices in anti-parallel within an integrated light source structure, so that they can be controlled independently from shared control lines.

Abstract: In a balancer board for a back light device, a plurality of shunt coils configured to transfer power from an inverter to a plurality of fluorescent tubes arrayed in a line are arrayed in a line in a direction which is the same as the direction in which the fluorescent tubes are arrayed, and respective patterns formed on front and rear surfaces of the balancer board so as to supply the power from the inverter to each of the plurality of shunt coils are formed such that the pattern formed on one surface is located apart from the pattern formed on the other surface with a predetermined distance left therebetween while mutually intersecting three-dimensionally in respective planes.

Abstract: A control device for regulating the constant output current of a flyback converter, the control device adapted to control the on time period and the off time period of a primary winding switch and including a first circuit adapted to multiply a first signal representative of current flowing through the primary winding and a second signal representative of an input voltage and outputting a signal representative of the multiplication, a second circuit adapted to compare the output signal of the first circuit and a third signal representative of the direct output voltage, the control device determining, on the basis of the output signal of the second circuit, the on time period and the off time period of the switch so that the output signal of the first circuit is equal to the signal representative of the direct output signal to have the output current of the flyback converter constant.

Abstract: A ballast (10) for powering one or more gas discharge lamps (30,40) includes an inverter (100), an output circuit (200), a filament heating control circuit (300), and a control circuit (500). During a lamp filament detection period prior to startup of inverter (100), control circuit (500) monitors a signal within output circuit (200) in order to determine the number of lamps with intact filaments that are present at the ballast output connections (202, 204, . . . , 210, 212). During a lamp type detection period following startup of inverter (100), control circuit (500) monitors a current within filament heating control circuit (300) in order to determine the type of lamp(s) present at ballast output connections (202, 204, . . . , 210, 212). The determinations as to the number of lamps and the type of lamps are utilized by control circuit (500) to provide an appropriate level of heating to the lamp filaments.

Abstract: An LED lighting system includes a power supply module, a data input line routed through the power supply module, an AC power input, and an LED fixture. The power supply module includes a power supply unit and an AC power cable. The AC power input is electrically connected to the power supply unit and the AC power cable. The LED fixture is electrically connected to an output of the power supply unit and the data input cable, and includes one or more LED assemblies disposed on a circuit board, a data signal output, and a power output. The AC power cable may be routed through the LED fixture.

Abstract: A device and method that automatically corrects the color of a dome light display device. An dome light display device may include one or more colored light emitting diodes (LEDs) arranged in a row, a photodetector disposed with the one or more LEDs in the row and a measurement circuit is configured to receive an electrical signal from the photodetector and compare the electrical signal to a reference signal associated with an intensity of light for a particular color of light and adjust the intensity of light emitted from the one or more LEDs based on the reference value.

Abstract: There is provided an LED drive circuit to which a light control signal phase-controlled by a phase-control light controller is inputted and that controls a light emission portion having a plurality of LED loads that emit light of different color tones. The LED drive circuit includes a light control/color control portion that, based on the light control signal inputted, adjusts a current to be passed through each of the LED loads thereby to perform light control and color control of the light emission portion.

Abstract: A constant current controlling part of an LED array driving apparatus includes a PWM IC including an RT/T terminal for outputting a sawtooth wave voltage, a COMP terminal for receiving a comparison voltage to be compared with the sawtooth wave voltage, an output terminal for outputting a pulse signal that is turned off during an interval where the sawtooth wave voltage is higher than the comparison voltage and turned on during an interval where the sawtooth wave voltage is lower than the comparison voltage, and a comparison voltage setter setting the comparison voltage inputted to the COMP terminal. When an overvoltage is applied to the LED array or the LED array is to be turned off by an external dimming control signal, the comparison voltage setter sets the comparison voltage to a value lower than a lower limit of the sawtooth wave voltage.

Abstract: An LED controller application specific integrated circuit includes a host interface and a PWM module. The PWM module is configured to control a plurality of LED devices, and comprises a PWM data buffer, an arithmetic core and a plurality of PWM channels. The PWM data buffer is configured to store PWM turning-point data from the host. The arithmetic core is configured to generate PWM data according to the PWM turning-point data stored in the PWM data buffer. The plurality of PWM channels are configured to receive the PWM data, and each comprises a PWM controller and a PWM I/O interface. The PWM controller is configured to control the operation of the PWM channel. The PWM I/O interface is configured to connect to an LED device.

Abstract: Color temperature of a lighting apparatus that includes a first LED that emits a white light with a first color temperature and a second LED that emits a white light with a second color temperature is managed. The two LEDs are connected in parallel anode to cathode so that current flowing in one direction turns on the first LED and current flowing in the opposite direction turns on the second LED. A controller manages a duty cycle of an alternating current flowing through the two LEDs to control the color temperature and/or the brightness of the lighting apparatus.

Abstract: A brightness control apparatus configured to perform brightness control for backlights formed by plural light-emitting elements for a display screen, including: a pulse control signal transmit unit configured to transmit a pulse control signal for performing driving control on the plural light-emitting elements based on a preset brightness control signal; a voltage control unit configured to control a voltage of the pulse control signal obtained by the pulse control signal transmit unit for each set of light-emitting elements of the same color so as to correct brightness variation in a regular state for the plural light-emitting elements; and a current control unit configured to control a current for each of the plural light-emitting elements based on a voltage value obtained by the voltage control unit so as to correct brightness variation due to temperature change or temporal change.

Abstract: A portable lighting system including a housing having an elongated slot formed in a surface of the housing. The slot being sized to receive a rod therein via an opening in the slot. The system further including a retention member movable between a closed position and an opened position, wherein the closed position provides at least a portion of the retention member blocking at least a portion of the upper opening of the slot and the opened position includes the retention member not blocking the upper opening of the slot. The system also having a light source including a plurality of lights oriented in different directions.

Abstract: A powerline communication control system for controlling a lighting unit, such as an LED lighting unit, including a master controller for receiving lighting unit control inputs from a lighting controller and generating corresponding lighting unit command outputs in a lighting system command format and transmission mode and superimposing the lighting unit command outputs onto the power distribution system and at least one lighting slave unit for receiving the lighting command signal, separating the lighting command signal from the power signal and for providing lighting unit control commands to the at least one lighting unit to control illumination thereof.

Abstract: An electronic circuit designed to reduce energy consumption by toggling between a plurality of conventional or electronic fluorescent lighting ballasts within a given fixture, and where said toggle circuit shall increase or decrease fixture light output levels according to immediate requirements. Toggle circuit may be remotely controlled from conventional Mains wall switch or other such means. Initial applications of Mains power automatically provides the minimum of light levels. Additional momentary interruptions to Mains power provides varied and/or additional lighting levels.

Abstract: An AC-driven LED circuit 10 includes a first parallel circuit 12 having a first branch 14 and a second branch 16 which connect at first and second common point 18, 20. The common points 18, 20 provide input and output for an AC driving current from a driver of the circuit. The first branch 14 has a first LED 26 and a second LED 28, the first LED 26 being connected to the second LED 28 in opposing series relationship with the inputs of the first and second LEDs 26, 28 defining a first branch junction 34. A second branch 16 has a third LED 30 and a fourth LED 32, the third LED 30 is connected to the fourth LED 32 in opposing series relationship with the outputs of the third and fourth LEDs 30, 32 defining a second branch junction 36. Improvement in performance and scalability is provided by adding n diodes to a given parallel circuit and x cross connecting circuit branch diodes (40, 44) and providing one or more parallel circuits (15) in series and or parallel.

Abstract: A flicker-free illumination apparatus (28) for a code reader (10) has an illumination control (26) which is configured for a pulsed operation with an illumination intensity varying between light pulses (30) and pulse pauses (32). The illumination control (26) is further configured to maintain a non-zero illumination intensity during the pulse pauses (32), such that a basic intensity (34) remains.

Abstract: A light-emitting device (10) includes a substrate (2) including electrodes, a first group (3) including a plurality of blue light-emitting diode elements that are disposed on the substrate and electrically connected to the electrodes, a second group (4) including a plurality of blue light-emitting diode elements that are disposed on the substrate and electrically connected to the electrodes, a fluorescent layer (3) disposed to receive light from the first group of blue light-emitting diode elements, and a phosphorescent layer (4) disposed to receive light from the second group of blue light-emitting diode elements.