filament (redirected from filament focal spot size)

filament, in astronomy: see chromosphere.

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filament

1. the thin wire, usually tungsten, inside a light bulb that emits light when heated to incandescence by an electric current

2. Electronics a high-resistance wire or ribbon, forming the cathode in some valves

3. a single strand of a natural or synthetic fibre; fibril

4. Botany

a. the stalk of a stamen

b. any of the long slender chains of cells into which some algae and fungi are divided

5. Ornithol the barb of a down feather

6. Anatomy any slender structure or part, such as the tail of a spermatozoon; filum

7. Astronomy

a. a long structure of relatively cool material in the solar corona

b. a long large-scale cluster of galaxies

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filament [′fil·ə·mənt]

(astronomy)

A prominence, seen as a dark marking on the solar disk.

(botany)

The stalk of a stamen which supports the anther.

A chain of cells joined end to end, as in certain algae.

(electricity)

Metallic wire or ribbon which is heated in an incandescent lamp to produce light, by passing an electric current through the filament.

(electronics)

A cathode made of resistance wire or ribbon, through which an electric current is sent to produce the high temperature required for emission of electrons in a thermionic tube. Also known as directly heated cathode; filamentary cathode; filament-type cathode.

(invertebrate zoology)

A single silk fiber in the cocoon of a silkworm.

(metallurgy)

A long, flexible metal wire drawn very fine.

(science and technology)

A long, flexible object with a small cross section.

(textiles)

A single continuous manufactured fiber which is extruded from a spinneret and joined with others to make a thread.

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filament

An incandescent lamp filament whose form and construction are designated by a letter: S, straight wire; C, coil; CC, coiled coil.