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These bulbs tend to be transparent white or colors, and are often ornately designed with crystal-like patterns. Later bulbs called C 7 + 1 ⁄ 2, have diameters of seven and a half 1/8th inches (15 ⁄ 16 in, or 24 mm) using an E12 candelabra base; however, these have a blunt shape (and should therefore be called B 7 + 1 ⁄ 2, or B24).
A Crookes radiometer in action. The radiometer is made from a glass bulb from which much of the air has been removed to form a partial vacuum.Inside the bulb, on a low-friction spindle, is a rotor with several (usually four) vertical lightweight vanes spaced equally around the axis.
A 230-volt LED filament light bulb, with a B22 base. The filaments are visible as the four yellow vertical lines. A LED filament light bulb is a LED lamp which is designed to resemble a traditional incandescent light bulb with visible filaments for aesthetic and light distribution purposes, but with the high efficiency of light-emitting diodes (LEDs).
Incandescent light bulbs and halogen lamps are most commonly used today. In the early and middle parts of the 20th century, low-cost opaque projectors were produced and marketed as toys for children. In educational settings, the specific role of the opaque projector has been superseded first by the overhead projector and later the document ...
The advent of miniature lights found the adaptation of twinkle bulbs as flasher bulbs, which interrupt the entire series circuit of anywhere from 10 to 50 bulbs when powered from 120-volt mains electricity (in North America). These are easily recognizable by their red tips on an otherwise unpainted clear white bulb, and are available in the ...
A formula from a 1968 US patent consisted of water and a transparent, translucent, or opaque mix of mineral oil, paraffin wax, and carbon tetrachloride. [3] p. 2, line 30 The clear water or mineral oil can optionally be coloured with translucent dyes. Common wax has a density much lower than that of water and would float on top at any temperature.
The device is simple: a transparent two-liter bottle is filled with water plus a little bleach to inhibit algal growth and fitted into a hole in a roof. The device functions like a deck prism : during daytime the water inside the bottle refracts sunlight, delivering about as much light as a 40–60 watt incandescent bulb to the interior.
Clear transparent incandescent lamps give off a sharp light, which is unpleasant to many people, and also makes it hard to see objects close to the lamp. In 1920, General Electric developed a 30 watt light bulb that had outside etching as a frosting effect.