(American spelling) Alternative form of optical fibre

(British spelling) A thin, transparent, flexible fibre, made of glass or plastic, used for transmitting light.

Of, or relating to fibre optics, or to optical fibre.

The colours of the rainbow. / (physics) The distribution of colours produced when white light passes through a prism. / (astronomy, physics) The range of frequencies of visible light.

(optics) A disk of high-quality quartz glass having at least one side ground and polished with a deviation in flatness less than 50 nanometers all over, and a surface quality of 5 microfinish or less; used, in an interferometer, to measure the flatness of other surfaces.

(astronomy) A star that appears as a double due to an optical illusion; in reality, the stars may be far apart from each other.

The optical axis. / (crystallography, mineralogy) The direction in which a ray of light passing through a crystal does not suffer double refraction.

plural of optical mouse

(computing) A mouse (pointing device) that uses a light source and a light detector (for example, an LED and an array of photodiodes) to detect movement, as opposed to the earlier mechanical mouse.

A scientific instrument that uses lasers to manipulate objects on the micron scale as if by using tweezers.