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.

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.

plural of optical switch

plural of optical microscope

(physics) The rotation of the plane of polarization of plane polarized light as it passes through a chiral medium

That does not involve vision / That does not use optics