In optical communications, a device used to reduce the power level of an optical signal.
Note 1: Optical attenuators used in fiber optic communications systems may use a variety of principles for their functioning. Those using the gap-loss principle are sensitive to the modal distribution ahead of the attenuator, and should be used at or near the transmitting end, or… (Read More →)

1. Of a refractive or reflective optical element, the straight line that is coincident with the axis of symmetry of the surfaces.
Note: The optical axis of a system is often coincident with its mechanical axis, but it need not be, e.g., in the case of an off-axis parabolic reflector used to transmit signals to, or receive signals from, a… (Read More →)

See beamsplitter.

See fiber optic cable.

See cable assembly.

The optical signal that results from an optical conversion of an synchronous transport signal 1 (STS-1 signal). It is this signal that will form the basis of the interface. [T1.105-1988]

A region bounded by two or more mirrors that are aligned to provide multiple reflections of lightwaves.
Note: The resonator in a laser is an optical cavity. In this sense, synonym resonant cavity.

A device used for optical character recognition.

The machine identification of printed characters through use of light-sensitive devices.

Deprecated synonym for optical fiber.