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Abertura mecánica
| Глоссарий по архивному хранению медийных материалов |
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Numerical aperture (na), английский
- A measure of the angular acceptance for a fiber, approximately the sine of the half-angle of the acceptance cone. the na of an optical fiber defines a characteristic of the fiber in terms of its acceptance of incoming light
- The sine of half the angle over which a fiber can accept light. strictly speaking, this is multiplied by the refractive index of the medium containing the light, but for air the index is almost equal to 1. the light-gathering ability of a fiber; the maximum angle to the fiber axis at which light will be accepted and propagated through the fiber. na = sin a, where a is the acceptance angle. na also describes the angular spread of light from a central axis, as in exiting a fiber, emitting from a source, or entering a detector.
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Lente de foco variable (trafocador), испанский
Norma de televisión ntsc ., испанский
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