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A rushlight is a type of candle or miniature torch formed by soaking the dried pith of the rush plant in fat or grease. For several centuries, rushlights were a common source of artificial light for poor people throughout the British Isles. [1] They were extremely inexpensive to make.
In visual perception, flicker is a human-visible change in luminance of an illuminated surface or light source which can be due to fluctuations of the light source itself, or due to external causes such as due to rapid fluctuations in the voltage of the power supply (power-line flicker) or incompatibility with an external dimmer.
A twinkle bulb is a special type of light bulb which blinks on and off for decorative effect. They are most commonly used on Christmas lights and other string lights, but can also be used for other ornamental purposes like electric jack-o-lanterns for Halloween and replica traffic lights.
A dyno torch, dynamo torch, or squeeze flashlight is a flashlight or pocket torch which generates energy via a flywheel. The user repeatedly squeezes a handle to spin a flywheel inside the flashlight, attached to a small generator/dynamo, supplying electric current to an incandescent bulb or light-emitting diode. The flashlight must be pumped ...
Flameless candles display flickering light, simulating real flames. As a decorative element, the design of a flameless candle is relatively versatile. The body or "housing" of the device is commonly cylindrical, containing a battery pack and an often flame-shaped LED lamp atop the candle. Many manufactures use LED lights with a sporadic ...
Power-line flicker is a visible change in brightness of a lamp due to rapid fluctuations in the voltage of the power supply. The voltage drop is generated over the source impedance of the grid by the changing load current of an equipment or facility.
Adjusting the strobe frequency can make the droplets seemingly move slowly up or down. Depending upon the frequency of illumination there are different names for the visual effect. Up to about 80 Hertz or the flicker fusion threshold it is called visible flicker. From about 80 Hertz to 2000 Hertz it is called the stroboscopic effect (this article).
New lighting systems have not used magnetic ballasts since the turn of the century, however some older installations still remain. Fluorescent lamps with magnetic ballasts flicker at a normally unnoticeable frequency of 100 or 120 Hz (twice of the utility frequency; the lamp is lit on both the positive and negative half-wave of a cycle).