An optical beam is directed at the tissue, and a small portion of this light that reflects from sub-surface features is collected.

An acousto-optic deflector spatially controls the optical beam.

After scanning, the optical beam must be properly projected into the eye.

The acousto-optic interaction also makes it possible to modulate the optical beam by both temporal and spatial modulation.

A simple method of modulating the optical beam travelling through the acousto-optic device is done by switching the acoustic field on and off.

Many applications of diode lasers primarily make use of the "directed energy" property of an optical beam.

This is not dissimilar from the optical beams used as safety devices in motorized garage doors or as triggers in alarm systems.

For the same reasons, FELs can generate high quality, nearly diffraction limited, optical beams.

This component (underneath the microstrip line) acts to tip the magnetization, M, along the propagation direction of the optical beam.

A powerful laser in the way of an optical beam which replaces the beam with stronger one also is not an amplifier.