An optical mouse uses a beam of light and an optical sensor to detect movement over a surface -- there are no moving parts.

CNN: Review: Apple Pro Mouse

The new technology places glass optical fibers, which contain a laser diode that sends a signal beam into the optical, into the flutes.

FORBES: Fiber-Optic Sensors Set Stage for Extreme Snipers

Moreover, engineers have worked out how to make laser beams more intense by using short lengths of optical fibre to narrow the beam.

ECONOMIST: Monitor

This generates the coherent light of a laser beam in the core of a long, thin optical fibre.

ECONOMIST: Solar power from space

Optical correlators, meanwhile, work by encoding images on to a beam of light and, using a special lens, transforming them into their Fourier components building-blocks that encode the thickness and direction of lines in the image, but not their position.

ECONOMIST: Optical recognition

With mobeam's technology, the Galaxy S4 can "beam" traditional 1D barcode data to any laser scanner with no new equipment, such as optical scanners or backend systems, required by the retailer.

ENGADGET: Samsung partners with Mobeam to offer scannable bar codes on the Galaxy S 4