(physics) The general field of study that employs the wavelike character of neutrons.

(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.

The art and science of vision and eye care.

An optical system in which prisms and/or mirrors are used to reduce the overall physical length of the system.

Misspelling of ophthalmologist.

regarding or using optics

In an optimistic manner.

(astronomy, optics) An optical system in telescopes that reduces atmospheric distortion by dynamically measuring and correcting wavefront aberrations in real time, often by using a deformable mirror.

plural of optician

plural of optical illusion