These forces acting transversely to the fiber axis make up the closeness of a fiber.

They are fibers in which the chain molecules are highly oriented along the fiber axis, so the strength of the chemical bond can be exploited.

In fiber diffraction the scattering pattern does not change, as the sample is rotated about a unique axis (the fiber axis).

In the ideal pattern the fiber axis is called the meridian, the perpendicular direction is called equator.

The reason is that the fiber axis and the incident beam (X-rays, electrons, neutrons) cannot be perfectly oriented perpendicular to each other.

Rays of light enter the fiber with different angles to the fiber axis, up to the fiber's acceptance angle.

The nanotubes were well dispersed and aligned along fiber axis.

At an end face of an optical fiber, the angle between an input ray and the fiber axis.

If the end face of the fiber is perpendicular to the fiber axis, the launch angle is equal to the angle of incidence.

For drawn metal wires the cylindrical fiber axis turned out as the sample direction around which preferred orientation is typically observed (see below).