Burst dimming

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Burst dimming is a method to control dimming of cold cathode fluorescent lamps (CCFLs) and LEDs by using pulse width modulation (PWM) at approximately 100-300 Hz which is supposed to be above the noticeable flicker limit for the human eye. [1] This technique is sometimes used with TFT displays to control backlighting. An alternative dimming method is to control lamp current.

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Stage lighting

Stage lighting is the craft of lighting as it applies to the production of theater, dance, opera, and other performance arts. Several different types of stage lighting instruments are used in this discipline. In addition to basic lighting, modern stage lighting can also include special effects, such as lasers and fog machines. People who work on stage lighting are commonly referred to as lighting technicians or lighting designers.

Pulse-width modulation modulation technique

Pulse-width modulation (PWM), or pulse-duration modulation (PDM), is a method of reducing the average power delivered by an electrical signal, by effectively chopping it up into discrete parts. The average value of voltage fed to the load is controlled by turning the switch between supply and load on and off at a fast rate. The longer the switch is on compared to the off periods, the higher the total power supplied to the load. Along with maximum power point tracking (MPPT), it is one of the primary methods of reducing the output of solar panels to that which can be utilized by a battery. PWM is particularly suited for running inertial loads such as motors, which are not as easily affected by this discrete switching, because their inertia causes them to react slowly. The PWM switching frequency has to be high enough not to affect the load, which is to say that the resultant waveform perceived by the load must be as smooth as possible.

Fluorescent lamp Light source

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Cold cathode Type of electrode and part of cold cathode fluorescent lamp.

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Lighting deliberate use of light to achieve a practical or aesthetic effect

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Hiram Maxim American-born inventor

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Automotive lighting lighting system of a motor vehicle

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Electrical ballast used to stabilize the current flow in lamps

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Cove lighting Form of indirect lighting

Cove lighting is a form of indirect lighting built into ledges, recesses, or valances in a ceiling or high on the walls of a room. It directs light up towards the ceiling and down adjacent walls. It may be used as primary lighting, or for aesthetic accent, especially to highlight decorative ceilings. Cove lighting is valued because it hides the fixtures, and because it provides a very even light.

A lighting control system is an intelligent network-based lighting control solution that incorporates communication between various system inputs and outputs related to lighting control with the use of one or more central computing devices. Lighting control systems are widely used on both indoor and outdoor lighting of commercial, industrial, and residential spaces. Lighting control systems serve to provide the right amount of light where and when it is needed.

Stage lighting instrument device that emits light to illuminate performer

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Multifaceted reflector

A multifaceted reflector light bulb is a reflector housing format for halogen as well as some LED and fluorescent lamps. MR lamps were originally designed for use in slide projectors, but see use in residential lighting and retail lighting as well. They are suited to applications that require directional lighting such as track lighting, recessed ceiling lights, desk lamps, pendant fixtures, landscape lighting, retail display lighting, and bicycle headlights. MR lamps are designated by symbols such as MR16 where the diameter is represented by numerals indicating units of eighths of an inch. Common sizes for general lighting are MR16 and MR11, with MR20 and MR8 used in specialty applications. Many run on low voltage rather than mains voltage alternating current so requiring a power supply.

Track lighting

Track lighting is a method of lighting where light fixtures are attached anywhere on a continuous track device which contains electrical conductors. This is in contrast to directly routing electrical wiring to individual light positions. Tracks can either be mounted to ceilings or walls, lengthwise down beams, or crosswise across rafters or joists. They can also be hung with rods from especially high places like vaulted ceilings.

LED lamp light source

An LED lamp or LED light bulb is an electric light for use in light fixtures that produces light using one or more light-emitting diodes (LEDs). LED lamps have a lifespan many times longer than equivalent incandescent lamps, and are significantly more efficient than most fluorescent lamps, with some manufacturers claiming LED chips with a luminous efficacy of up to 303 lumens per watt. However, LED lamps require an electronic LED driver circuit when operated from mains power lines, and losses from this circuit means that the efficiency of the lamp is lower than the efficiency of the LED chips it uses. The most efficient commercially available LED lamps have efficiencies of 200 lumens per watt (Lm/W). The LED lamp market is projected to grow by more than twelve-fold over the next decade, from $2 billion in the beginning of 2014 to $25 billion in 2023, a compound annual growth rate (CAGR) of 25%. As of 2016, many LEDs use only about 10% of the energy an incandescent lamp requires.

SeaChanger Color Engine

The SeaChanger Color Engine is an electro-mechanical device that is used to control light color in entertainment-industry lighting applications. The unit employs four overlapped color filter wheels, inserted into a light beam near its source, to produce colored light. This is in contrast to color scrollers, which insert color filter ribbons into a light beam. The color engine, which was released by Ocean Thin Films in 2005, is designed to fit into the Source Four lighting instrument made by Electronic Theatre Controls.

Vari-Lite is a brand of automated, variable-colour stage lighting systems. Their intelligent lighting fixtures are commonly used in theatre, concerts, television, film and corporate events.

References

  1. "Electrical Engineering Glossary Definition for Burst Dimming - Maxim/Dallas". 070925 maxim-ic.com