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  2. Electromagnetic shielding - Wikipedia

    en.wikipedia.org/wiki/Electromagnetic_shielding

    A conductive enclosure used to block electrostatic fields is also known as a Faraday cage. The amount of reduction depends very much upon the material used, its thickness, the size of the shielded volume and the frequency of the fields of interest and the size, shape and orientation of holes in a shield to an incident electromagnetic field.

  3. Blacklight - Wikipedia

    en.wikipedia.org/wiki/Blacklight

    A blacklight, also called a UV-A light, Wood's lamp, or ultraviolet light, is a lamp that emits long-wave ultraviolet light and very little visible light. [ 1 ] [ 2 ] [ 3 ] One type of lamp has a violet filter material, either on the bulb or in a separate glass filter in the lamp housing, which blocks most visible light and allows through UV ...

  4. Optical filter - Wikipedia

    en.wikipedia.org/wiki/Optical_filter

    Ultraviolet (UV) filters block ultraviolet radiation, but let visible light through. Because photographic film and digital sensors are sensitive to ultraviolet (which is abundant in skylight) but the human eye is not, such light would, if not filtered out, make photographs look different from the scene visible to people, for example making ...

  5. Halogen lamp - Wikipedia

    en.wikipedia.org/wiki/Halogen_lamp

    For example, a bulb operated at 5% higher than its design voltage would produce about 15% more light, and the luminous efficacy would be about 6.5% higher, but would be expected to have only half the rated life. Halogen lamps are manufactured with enough halogen to match the rate of tungsten evaporation at their design voltage.

  6. Fluorescent lamp - Wikipedia

    en.wikipedia.org/wiki/Fluorescent_lamp

    The spectrum of light emitted from a fluorescent lamp is the combination of light directly emitted by the mercury vapor, and light emitted by the phosphorescent coating. The spectral lines from the mercury emission and the phosphorescence effect give a combined spectral distribution of light that is different from those produced by incandescent ...

  7. Induction lamp - Wikipedia

    en.wikipedia.org/wiki/Induction_lamp

    Around 2000, a system was developed that concentrated radio frequency waves into a solid dielectric waveguide made of ceramic which energized a light-emitting plasma in a bulb positioned inside. This system, for the first time, permitted an extremely bright and compact electrodeless lamp.

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  9. Pearson–Anson effect - Wikipedia

    en.wikipedia.org/wiki/Pearson–Anson_effect

    Like other relaxation oscillators, the neon bulb oscillator has poor frequency stability, but it can be synchronized to an external periodic voltage applied in series with the neon bulb. Even if the external frequency is different from the natural frequency of the oscillator, the peaks of the applied signal can exceed the breakdown threshold of ...