Introduction and Components of Crackle Tubes
– Crackle tubes are plasma lamps used in museums, night clubs, and movie sets.
– They consist of a double-walled glass tube filled with phosphor-coated glass beads.
– A 5-14kV transformer produces a low power gas discharge in the bead-filled cavity.
– Crackle tubes are filled with noble gases like neon, argon, or xenon.
Features and Appearance of Crackle Tubes
– Crackle tubes can be cylindrical or made into different shapes, even flat plates.
– The filaments can be made into different colors by combining chemicals with the base phosphor.
– Filaments can change color along the length of the tube by using glass beads with different chemical coatings.
– Multiple simultaneous filaments of different colors can be achieved through combined chemical coatings.
– Crackle tubes appear white in their off state but can change color when turned on.
Functionality and Behavior of Crackle Tubes
– Crackle tubes produce filaments of light due to the electrical energy exciting the phosphor.
– The lightning filaments are forced around and between the phosphor-coated glass beads.
– The electrical discharge transitions from one color layer to another, creating changing filament colors.
– Crackle tubes are not very bright compared to fluorescent lights or incandescent lamps.
– They are best viewed in darkness and can respond to music or ambient noise.
Applications and Usage of Crackle Tubes
– Crackle tubes are commonly used in museums, night clubs, and movie sets for entertainment purposes.
– They create an appealing appearance and simulate lightning.
– Crackle tubes are also used as props, such as in the representation of Star Trek’s Borg.
– Their transformers can be linked to an acoustic modulator for music or ambient noise response.
– The gas-filled cavity acts as an electron transfer medium.
Related Topics
– Electronics portal is a useful resource for further information on crackle tubes.
– Plasma physics is a related field to understand the behavior of crackle tubes.
– A list of light sources can provide additional examples of lighting devices.
– Luminglas is a trademarked name for flat crackle tubes.
– The website www.strattman.com provides information on Luminglas. Source: https://en.wikipedia.org/wiki/Crackle_tube
This article needs additional citations for verification. (August 2008) |
A crackle tube is a type of plasma lamp that is used most commonly in museums, night clubs, movie sets, and other applications where its appearance may be appealing for entertainment. Such a device consists of a double walled glass tube with a hollow center. The cavity between the inner and outer glass tubes is filled with thousands of small phosphor coated glass beads. A 5–14 kV transformer produces a low power gas discharge in the bead filled cavity, producing filaments of light that simulate lightning. Crackle tubes get their name not because of the sound they produce but rather because of the appearance of their internal behavior. The "lightning" (filaments or streamers) is forced around and in between the phosphor-coated glass beads, due to the beads' dielectric nature. In so doing, the phosphor is excited by the electrical energy and fluoresces producing visible light. Like plasma globes, crackle tubes respond to touch; the filaments appear to be "attracted" toward the point of contact and usually become more luminous (brighter) as the electricity is grounded. The tubes are also filled with a noble gas like neon, argon, or xenon which acts as the electron transfer medium of the cavity. The gas is typically below atmospheric pressure.
Typically, crackle tubes are cylindrical, however, they can be made into virtually any shape, even flat plates (trademarked by the name "Luminglas" ). The filaments can also be made to any color by combining different chemicals with the base phosphor. The chemical that is used to produce blue filaments is also responsive to ultraviolet light. The filaments can change color as they progress along the length of the tube. This effect is created by using glass beads with different chemical coatings on them, and the color of the filament changes as the electrical discharge transitions from one color layer to another. Chemical coatings can also be combined onto a single coating, allowing for a crackle tube to have multiple simultaneous filaments of several different colors.
Crackle tubes appear white when viewed in their off state under normal lighting conditions. Their luminosity, or light intensity, depends on several factors, but generally crackle tubes are not very bright when compared to a fluorescent light or incandescent lamp. They are best viewed in darkness. Their transformers can also be linked to an acoustic modulator, allowing the tubes to 'respond' to music or ambient noise.
