Abstract: An electronic device indicating the use of a receptacle containing different fluids such as receptacles for foods such as ketchup sauce, powder such as talcum or gel such as toothpaste or any product having this presentation. The receptacles are of the type comprising a top or a means to extract the product to be utilized. The electronic device is included in the receptacle independently of the size thereof and makes no contact with the product contained by the receptacle.

Abstract: A system for controlling multiple light sources is provided. The system includes a controller, a digital to analog converter (DAC), and at least one power amplifier. The controller is configured for receiving light control data for at least one light circuit, and for determining a digital luminance signal and an encoded address for each light circuit according to the light control data. The DAC is connected to the controller and configured for receiving the digital luminance signal and the encoded address for each light circuit, converting the digital luminance signal into an analog luminance signal, and for outputting the analog luminance signal according to the encoded address. Each power amplifier is connected to the DAC, and is configured for amplifying the analog luminance signal for the light circuit so as to drive the light circuit to control a corresponding light source.

Abstract: An illuminatable apparatus includes a fabric sheet containing fiber optic rods interwoven with fabric threads. The ends of the fiber optic rods are bundled together to form a ferrule which is removably insertable into a holder carrying a light source and a power source. An outer ferrule can be fixed over the sleeve-like ferrule or robust applications. The holder may be removably attached to articles of clothing. The illuminatable fabric sheet can be used as an optical bandage, in a medical cast, in a negative pressure device, or in a bed pad/sheet, or in a therapeutic brace support.

Abstract: A discharge lamp lighting apparatus includes a switch circuit for DC/AC converting, a discharge lamp connected to a secondary winding of a transformer, a current detector detecting an AC output current of the discharge lamp, an error amplifier outputting an error signal to a detected current, a control circuit generating control signals that turn on/off the switching elements in such a way as to control the AC output current at a predetermined value, and a time division signal generator generating a time division signal at the start of an ON/OFF operation of the switching elements, wherein the time division signal delays a change in a burst dimming signal or has a predetermined inclination on the burst dimming signal. The error amplifier changes the error signal according to the time division signal from the time division signal generator.

Abstract: Ballasts with crest factor control are provided. During a transition to a given half cycle steady state, the current provided to reach the steady state is varied, such as turned off for a short period. This reduction during the transition may reduce or eliminate overshoot. The crest factor control is active, such as altering the timing or number of on/off/on switchings used to control crest factor. The active control may be based on any information, such as time, lamp voltage feedback, or other lamp dependent feedback.

Abstract: The IRS21681D is a fully integrated, fully protected 600V ballast control IC designed to drive all types of fluorescent lamps. The IRS21681D is based on the popular IR2166 control IC with additional improvements to increase ballast performance. PFC circuitry operates in critical conduction mode and provides high PF, low THD and DC bus regulation. The IRS21681D features include programmable preheat and run frequencies, programmable preheat time, programmable ignition ramp, programmable PFC over-current protection, and programmable end-of-life protection. Comprehensive protection features such as protection from failure of a lamp to strike, filament failures, end-of-life protection, DC bus under-voltage reset as well as an automatic restart function, have been included in the design. The IRS2168D has, in addition, closed-loop half-bridge ignition current regulation and a novel fault counter. The IRS21681D, unlike the IRS2168D, ramps up during ignition and shuts down at the first over-current fault.

Abstract: A voltage control apparatus (10) for an HID lamp includes a voltage control transformer circuit (20), and is connected between supply mains (22) and a high intensity discharge (HID) lamp. The HID lamp is started at full line voltage, and after a sufficient operating interval ensuring that the lamp has achieved a sustaining temperature, the operating voltage applied to the lamp is reduced, effecting considerable savings in energy use, with little or only an acceptably small decrease in light output from the lamp. Further, the voltage control apparatus include a circuit portion responsive to voltage transients on the AC line, and which effects restarting of the HID lamp in the event a voltage transient occurs which is sufficiently long (i.e., about ½ cycle) as to extinguish the HID lamp.

Abstract: A lighting control system includes an enhanced occupancy sensor and/or an enhanced power pack, allowing for more sophisticated and/or accurate lighting control and energy management capability. In one example, the occupancy sensor provides additional information, such as information about movement detected in the monitored area, in the form of a signal superimposed on the occupancy signal, and a specialty power pack is configured to detect and respond to the superimposed information signal, thereby providing enhanced functionality to the lighting control system. The superimposed signal conveying the additional information is made high-speed/short-duration such that it is “invisible” to a conventional power pack and the occupancy sensor remains compatible with conventional power packs. The enhanced occupancy sensor may therefore be used seamlessly with both conventional and specialty power packs, and may be implemented as a “drop-in” component for legacy lighting control systems.

Abstract: A method, apparatus, and system for compensating for lamp lumen depreciation. The method includes operating the lamp under rated wattage for a period towards the first part of operating life of the lamp. Operating wattage is increased at one or more later times. Energy savings are realized. The increases also restore at least some light lost by lamp lumen depreciation. The apparatus uses a timer to track operating time of the lamp. A few wattage changes made at spaced apart times can be made in a number of ways, including changing capacitance to the lamp, or using different taps on the lamp ballast. In one aspect the invention pertains to solid state sources. The invention can pertain to a variety of applications including wide area lighting, indoor lighting, pathway lighting, parking lot lighting, street lighting, under-counter or -cabinet lighting, and others.

Abstract: A beacon for use at transportation hubs, such as airports, heliports, and marine vessels and for marking aviation obstructions. The beacon is modular in design and has a substantially cylindrical housing that includes a bottom portion, a window and a top portion, sealed by gaskets. The beacon is configured for outdoor use and is explosion-proof or, at least, explosion-resistant. The housing defines a cavity that abuts the window. A reflector and a light source, such as a light emitting diode (LED) or an array of LEDs, are mounted in the cavity of the housing. The beacon includes a control unit with a GPS transceiver unit and another control inlet/outlet. Using the control unit, the beacon can operate individually or in a coordinated manner with other beacons.

Abstract: A light source includes an discharge lamp including a first electrode and a second electrode emitting light by discharge between them, a drive unit performing a steady operation which supplies steady energy to the first and second electrodes and an initial operation which supplies energy to the first and second electrodes with an operation different from the steady operation before performing the steady operation, a determination unit determining states of the discharge lamp and a data storage unit storing plural initial power feeding conditions provided corresponding to states of the discharge lamp as examples of the initial operation and plural steady power feeding conditions provided corresponding to the states of the discharge lamp as examples of the steady operation, in which the drive unit performs the initial operation in any one of conditions selected from the plural initial power feeding conditions according to a determination result by the determination unit and performs the steady operation in any

Abstract: The present High Intensity Discharge electronic lamp ballast uses a “set of controls” that can be performed by controlling energy delivery by the “line side converter” to the “lamp side inverter”. This set of controls comprises: 1) open circuit voltage control, 2) breakdown voltage amplitude control, 3) glow-to-arc transition current control, 4) “initial arc development” current control, 5) “arc stabilization” current control, 6) lamp power control, 7) lamp dimming, 8) “lamp rectification” current control, and 9) short circuit and lamp fault protections. One of the primary advantages of this “line side converter” energy delivery control method is that it doesn't need to vary the lamp operating frequency to achieve the above-noted controls.

Abstract: A discharge lamp lighting apparatus for turning on a discharge lamp has a lighting condition in which a projection is formed at a tip of an electrode for electric discharge. In the discharge lamp lighting apparatus, when the polarity-reversal mode is the second mode, the inverter control circuit operates to generate the inverter control signal so that a DC component contained in the output current increases more than that in the first mode, when the polarity-reversal mode is the first mode, and it is detected that the lamp voltage is lower than a predetermined first voltage, the polarity-reversal mode control circuit changes the polarity-reversal mode into the second mode, and when the polarity-reversal mode is the second mode, and it is detected that the lamp voltage is higher than a predetermined second voltage, the polarity-reversal mode control circuit changes the polarity-reversal mode into the first mode.

Abstract: The output current of a ballast is dynamically limited when an over-temperature condition is detected in the ballast according to one of (i) a step function or (ii) a combination of step and continuous functions, so as to reduce the temperature of the ballast while continuing to operate it.

Abstract: A method for controlling average current. The method enables control of average current independent of instantaneous current. The average current is controlled by changing the number of unit pulses provided during a time interval. The unit pulses are used to switch the delivery of current to the load.

Abstract: A high frequency ballast for a metal halide lamp comprises a controller, a switch, and an oscillator. The controller selectively enables and disables the oscillator via the switch to ignite the lamp. The ignition method includes enabling the oscillator such that the oscillator provides the lamp with a pulse train comprising a rapid series of short ignition pulses, cools for a period of time, and provides an addition pulse train to the lamp if necessary to ignite the lamp. When the lamp ignites, the ballast maintains enablement of the oscillator.

Abstract: An electrically powered flame simulator comprises at least two light sources, an integrated circuit electrically connected to the light sources for intermittently illuminating at least one of the light sources independently of other light sources such that the light sources together provide the effect of a flickering movement, and a power source for providing power to the integrated circuit. The flame simulator may be mounted in a decorative or ornamental device such as a candle or fire log, or used on decorative clothing, or may be part of a hazzard or warning system. One or more solid state light sources may also be used.

Abstract: A light source controller is configured to control timings of driving the first and second light sources and the light-source light generator, so that the light-source light of two or more colors generated by the light-source light generator and the light-source light emitted from the second light source are cyclically generated, by setting a light-emitting period of at least one light-source light color having a higher luminous efficiency out of the two or more colors generated by the light-source light generator, shorter than those of the other light-source light colors, and setting a drive power of the first light source during generation of the light-source light color whose light-emitting period is set short, greater than a drive power of the first light source during generation of the other light-source light colors.

Abstract: The invention relates to a method for compensating the ageing-related loss of luminosity of an electroluminescence element, according to which the cumulative electrical energy supply, i.e. the integral of the supplied electrical power over the period of operation, is used as a criteria for the compensating regulation of the operating voltage. The processing unit continuously integrates the supplied electrical power over time. The relation between the operating voltage and the emission luminosity of the electroluminescence element is stored in the memory for different cumulative electrical energy supplies. The stored data can be defined by means of a model or estimated on the basis of empirical values. The relation can be stored in the form of values stored in a tabular manner or as an analytical function in the memory.

Abstract: An emergency lighting system includes a plurality of emergency lights and a plurality of emergency power systems. Each of the plurality of emergency power systems is electrically connected to a respective one of the plurality of emergency lights through a respective one of a plurality of power switches. The emergency lighting system also includes a plurality of processors. Each of the plurality of processors is electrically connected to a respective one of the plurality of emergency power systems and executes software that monitors a status of a respective one of the emergency power systems and controls a state of the plurality of power switches. The emergency lighting system also includes a plurality of radio transceivers. Each of the plurality of radio transceivers is electrically connected to a respective one of the plurality of processors and communicates with other radio transceivers in the plurality of radio transceivers that are in radio wave proximity.

Abstract: To provide a light source unit which can enhance luminance and a projector, a projector of the invention includes a light source unit comprising a luminescent wheel with luminescent light emitting portions to emit blue and green rays, a primary light source shining an excitation light to the luminescent light emitting portions, a secondary light source emitting a red ray, a light guiding optical system guiding the rays from the luminescent wheel and the ray from the secondary light source to the same optical path and a light source control means controlling the emissions from the respective light sources, wherein the light source control means turns on the secondary light source when the ray from the primary light source is shone onto a boundary between the luminescent light emitting portions to synthesize the rays from the luminescent wheel and the ray from the secondary light source to generate white ray.

Abstract: A dimmer switch has a user adjustable high-end trim. The dimmer switch includes a bidirectional semiconductor switch, such as a triac, for controlling the amount of power delivered from a source of alternating current power to a lighting load, such as an electric lamp. A user-adjustable timing circuit controls the conduction time of the triac from a minimum time to a maximum time. The maximum possible conduction time of the triac is the high-end trim. The minimum possible conduction time of the triac is the low-end trim. The timing circuit includes a user-accessible switch that allows a user to reduce the high-end trim from a first nominal level to a second reduced level, lower than the first level, without substantially affecting the low-end trim. The switch allows a user to switch a transient voltage suppressor into and out of parallel connection with a resistor that is part of an RC timing circuit for the triac.

Abstract: A control device for controlling driving of an LED includes: a driving section driving the LED, the driving section being formed including a switching element; a control value obtaining section obtaining a control value of n+m bits; and a controlling section controlling the driving of the LED by the driving section on a basis of the control value of the n+m bits obtained by the control value obtaining section such that a number of times of turning on the switching element in a predetermined period is controlled by a control value of n higher-order bits, an ON time at one of the times of turning on the switching element is controlled by a control value of m lower-order bits, and ON times of the switching element excluding the ON time at the one time of turning on the switching element are a predetermined time.

Abstract: In order to suppress cost of an initial investment by a user and running cost to the user to a low extent while substantially constantly maintaining an apparent illuminance, and further, to realize resource saving, in a case of using a fluorescent lamp FHF 32 as a discharge lamp La, a lamp supply power is started to be supplied from a value lower than 45 W as rated electric power at an initial period of an operation of the discharge lamp, a light adjustment signal is changed in response to an accumulated lighting time so that the lamp supply power can be a value higher than 45 W as the rated electric power on and after a rated lifetime of the discharge lamp La, whereby the lamp supply power (output of an inverter circuit 2) is adjusted.

Abstract: Exemplary embodiments provide a system, method and apparatus for regulating current in loads, such as in an array of independent pluralities of light emitting diodes (“LEDs”). An exemplary system comprises a multiplexer adapted to switch current to each independent string of LEDs; a first controller to maintain a substantially constant average current level to the plurality of LEDs; and a second controller to modulate a current amplitude and duration of time division multiplexing for each independent string of LEDs. Another aspect of the system provides for modulating the on time for switching current to maintain a substantially constant average current level and to respond and converge quickly to changing current reference levels.

Abstract: In a method of detecting arc discharge in a glow-discharge apparatus GD that has a high-frequency power source PS, a cutting pulse is output for time T1 to the high-frequency power source PS to stop a supply of power to the glow-discharge apparatus GD, when dVr/dt-dVf/dt increases over a first level, where Vf and Vr are a traveling-wave voltage and a reflected-wave voltage applied to the glow-discharge apparatus GD, respectively.

Abstract: To provide an image display apparatus having: an electron source; a light-emitting member for emitting a light by irradiation with electrons emitted from the electron source; an anode electrode, which is arranged being opposed to the electron source; a high-voltage generating circuit for generating a potential which rises in a predetermined period; a wiring for connecting the anode electrode to the high-voltage generating circuit; a comparator; a first circuit for applying a first potential satisfying a positive correlation with the potential on the wiring to the comparator; and a second circuit for applying a second potential, which continuously rises or rises in stepwise manner in the predetermined period, to the comparator. The comparator outputs a result of comparison between the first potential and the second potential.

Abstract: Controlling an arrangement of semiconductors of which different semiconductors emit light of different distinct colors is disclosed, whereby a feed forward control part, which is dependent on a junction temperature of semiconductors for each color, is operated with first intervals and is adjusted dependent on measure light output for each color with much longer second intervals.

Abstract: An illumination device with small light intensity loss, prevents deterioration of directivity, includes a white light source; a first light guiding unit disposed on the white light source optical axis, guiding white light from its source in a radially outward direction perpendicular to the optical axis; a second light guiding unit guiding light going in the radially inward direction to the optical axis; a unit rotating the first and second light guiding units about the optical axis; semiconductor light sources circumferentially disposed radially outward of the second light guiding unit, emitting light in the inward radial direction; and wavelength-range selecting units disposed outward of the first and second light guiding units on opposite sides in the radial direction at circumferential positions different from the semiconductor light sources, select light components in predetermined wavelength ranges of white light from the first light guiding unit and return the light components to the second light guidin

Abstract: A method includes rectifying AC power and controlling switching of first, second and third currents from and rectified power and a switching sequence that is locked to the AC cycle time by sensing an amplitude of at least one of the AC power and the rectified power. The first, second and third currents are conducted through corresponding first, second and third series of color light emitting devices of different colors. The switching sequence repeats at least twice each AC cycle time.

Abstract: A switching power converter has an input voltage source. An output load is coupled to the input voltage source. An inductive element is coupled to the load. A switch is coupled to the inductive element. A current reference input is provided. A control circuit is coupled to the switch and the current reference input for activating and deactivating the switch. The inductive element receives power from the input voltage source when the switch is activated and conducting continuous current. The control circuit deactivates the switch after a controlled delay time when the current in the inductive element and the switch exceeds the current reference input so that an average current in the inductive element is determined by a magnitude of the current reference input.

Abstract: A method of driving a lamp of a liquid crystal display device includes generating a control signal; generating a first drive signal using the control signal; generating a second drive signal by shifting a voltage level of the first drive signal; selectively outputting one of a high potential supply voltage and a low potential supply voltage in response to the second drive signal; transforming the selectively outputted voltage; and supplying the transformed voltage to a lamp.

Abstract: In a discharge lamp lighting apparatus, increase modulation on lamp current with a pulse is carried out according to a modulation signal. At a start-up of the discharge lamp or immediately thereafter, the increase modulation is restrained, and in a lighting steady state of the discharge lamp, the restraining of the increase modulation is released, and wherein when the restraining of the increase modulation is released, in a transition period from immediately after the start-up of the discharge lamp to the lighting steady state, the restraining of increase modulation is gradually released.

Abstract: In one embodiment, the present invention includes an electronic circuit for providing a power current to an LED lamp. The electronic circuit comprises a logic drive circuit, a VCO, a power switch, and a first current sensor. The VCO is coupled to provide a first logic control signal to the logic drive circuit. The power switch has a first terminal and second terminal coupled to deliver the power current to the LED lamp and a control terminal coupled to receive a power control signal from the logic drive circuit. The first current sensor is coupled to sense a peak current passing through the power switch and coupled to provide a second logic control signal to the logic drive circuit.

Abstract: A method for projecting at least one light beam may include lengthening at least in part a holding duration for at least one pixel with respect to at least one further pixel.

Abstract: Lighting systems for providing supplemental light to plants to facilitate plant growth and/or to provide supplemental lighting in situations where sunlight is insufficient. Lighting systems may use LED technology to deliver specific wavelengths of light to maximize utilization of the supplemental light for photosynthesis. By delivering light having one or more specific wavelengths, it is possible to use a light that consumes relatively little power (e.g., about 10 watts or less) while providing sufficient supplemental light to facilitate healthy plant growth. Lighting systems may include a light-sensor to facilitate control of the amount of light provided. For example, a light-sensor may be used to automatically adjust the amount (e.g., intensity or duration) of light provided when the amount of ambient light available to the plant dips below a predetermined level.

Abstract: A portable illumination device having a flexible arm housing with an integrally formed LED lamp that is attachable to an object. The flexible arm may include a head portion housing an LED lamp, the head portion being unitarily formed in the flexible arm as a single integral unit at the time of manufacture. The flexible arm may be comprised of a non-slip material, such as rubber, to aid in positioning the flexible arm to a desired position.

Abstract: A liquid crystal display television receiver projection system uses a controller responsive to a first signal by providing power to a first set of circuits of the system. The controller is responsive to a second signal by removing power from a second set of circuits of the system; A timer defines a time interval between an instance of a power off signal and an instance of a power on signal. In the event a user issues a power on command before the first interval has elapsed, power will be applied to circuits other than the lamp The lamp will remain de-energized until the first interval has elapsed. Therefore, a user is prevented from re-striking the lamp.

Abstract: Power management in a light emitting diode (LED) system having a plurality of LED strings is disclosed. A voltage source provides an output voltage to drive the LED strings. An LED driver monitors the tail voltages of the active LED strings to identify the minimum, or lowest, tail voltage and adjusts the output voltage of the voltage source based on the lowest tail voltage. The LED driver can adjust the output voltage so as to maintain the lowest tail voltage at or near a predetermined threshold voltage so as to ensure that the output voltage is sufficient to properly drive each active LED string with a regulated current in view of pulse width modulation (PWM) performance requirements without excessive power consumption.

Abstract: An intelligent light source for use with the test of a digital camera module provides a plurality of shapes of light. A fast light pulse is created with turn-on and turn-off transitions less than or equal to one microsecond. Other waveform shapes comprise a ramp and a sinusoid, and all shapes can be made to occur once or repetitively. The magnitude of the light has a range from 0.01 LUX to 1000 LUX, and the ramp has a ramp time that has a range from microseconds to 100 ms. The light comprises of a plurality of colors created by serial connected strings of LED devices, where the LED devices in a string emit the same color. The light emanating from the light source is calibrated using a photo diode and the control of a tester by adjusting offset voltages of a DAC controlling a current through the LED strings.

Abstract: Circuitry, which is compatible with incandescent light dimmers, is disposed within the screwbase of a compact fluorescent light, and sets driving frequencies for a mercury plasma, based, at least in part, on sensing the duty cycle of the incoming AC supply waveform. In this way, existing lighting infrastructure, including phase-cut dimmer circuits for incandescent light bulbs, may be preserved, and incandescent bulbs can be replaced with compact fluorescent lights equipped with circuitry in accordance with the present invention. In a further aspect, the circuitry synchronizes the bulb drive signals with the AC power line frequency.

Abstract: The systems and methods descried herein relate in part to intuitive methods for creation and design of lighting sequences, e.g., for theatrical, entertainment or advertising purposes, using a software interface. Additionally, the lighting sequences can be coordinated with control of additional devices. Also described herein is a controller capable of executing programs for lighting sequences and modifying the output and/or execution of the program based on external signals. In this way, the final output can be made responsive to external stimuli, or even interactive.

Abstract: A method for feeding electric power to a planar light-emitting element which includes a planar anode electrode, a planar cathode electrode, a light-emitting layer provided between the anode electrode and the cathode electrode, two or more anode terminal portions protruding from the anode electrode and one or more cathode terminal portions protruding from the cathode electrode. The method includes sequentially providing the electric power to the anode terminal portions.

Abstract: A lighting device operable to supply temporally appropriate light to a user comprises a light socket adapter interposed between a primary socket and a first type of lamp. The primary socket is connected to a switchable supply of electrical power. A first type of lamp includes wavelengths below 530 nm that are suppressive of melatonin production in a user viewing the light. There is a second type of lamp that supplies light substantially all above 530 nm so as to avoid suppressing melatonin production in a user viewing the light. The light socket adapter has at least one mode of operation in which automatic means causes the first and second types of lamp to be exclusively operable during respective predetermined periods of time.

Abstract: A discharge lamp ballast apparatus includes a fault detecting section 9b of a discharge lamp 6; a first storing section 10 for storing a fault detected; a lighting delay detecting section 9c-3 for detecting lighting delay time from beginning of starting operation to lighting of the discharge lamp; a reigniting voltage measuring section 9c-5 for measuring a discharge lamp voltage immediately after switching of polarity applied to the discharge lamp according to AC lighting; a measuring section 9c-6 for measuring a period of time during which a current does not flow by detecting a discharge lamp current immediately after switching the polarity applied to the discharge lamp according to the AC lighting; a going out counting section 9c-4 for counting a number of times of going out by detecting going out during lighting of the discharge lamp; and a second storing section 9c for storing the lighting delay, reigniting voltage, period of time during which the current does not flow, and number of times of going out as

Abstract: A cold-cathode tube driving apparatus wherein the number of booster transformers has been reduced and the increase in installation space and in cost has been suppressed. This cold-cathode tube driving apparatus comprises a booster transformer (2); a plurality of cold-cathode tubes (3-1 to 3-N); and a time division control circuit (control circuit 6 and time division FETs 4-1 to 4-N) for lighting one or more of the plurality of cold-cathode tubes (3-1 to 3-N) in a time division manner by use of a high frequency voltage after boosted by the booster transformer (2).

Abstract: An illumination brightness and color control system and method therefor are provided. A broadband light source monitor senses and samples a point light source for a luminous intensity signal value. Then, a corrected current value is computed based on a difference between the luminous intensity signal value and a target brightness/color value, and a driving current generated by a light source driver to drive the point light source is adjusted according to the corrected current value.

Abstract: A DC/DC converter device according to the present invention includes a plurality of resonant DC/DC converters connected in parallel, and a timing control circuit driving the plurality of resonant DC/DC converters at substantially the same frequency with a phase shift.

Abstract: A dimmable electronic ballast for an electrodeless discharge lamp comprises an inverter circuit, a resonance circuit, an induction coil and a start circuit. The start circuit has a variable time constant. The start circuit sweeps a drive frequency of the inverter circuit through a time constant for start or restart so that the voltage applied across the coil is raised from voltage lower than start voltage and restart voltage for starting and restarting the lamp to voltage higher than the start voltage and the restart voltage. The time constant for start during a start period for starting the lamp is larger than the time constant for restart during a restart period for restarting the lamp.

Abstract: A two-wire dimmer for control of a lighting load from an alternating-current (AC) power source includes a semiconductor switch, a power supply, and a control circuit. The power supply includes an energy storage input capacitor that is able to charge only when the semiconductor switch is non-conductive. The control circuit continuously monitors the voltage on the input capacitor and automatically decreases the maximum allowable conduction time of the semiconductor switch when the voltage falls to a level that will not guarantee proper operation of the power supply. The dimmer of the present invention is able to provide the maximum possible conduction time of the semiconductor switch at high end (i.e., maximum light intensity) while simultaneously ensuring sufficient charging time for proper operation of the power supply, and hence, the dimmer.