Photonics Dictionary: R

Conductor element for use in integrated electro-optic systems that measures current flowing through it.

In positioning, rotation about the line of sight or direction of travel.

Also known as a turned-down edge. A rapid change of curvature near the edge in a lens or prism surface.

Rolling shutter artifacts are distortions or visual anomalies that can occur in images or videos captured by cameras with rolling shutter sensors. A rolling shutter is a type of image sensor that...

A defect in the cleaved end face of an optical fiber in which a portion of the edge has broken away; the complement of lip.

A transparent plate ruled with black lines and equal, clear spaces. It is used as a multiple knife-edge for testing a concave mirror.

More efficient than the Foucault knife-edge test, this test examines curved mirrors by using a transmission grating with 40 to 200 lines per inch in place of the knife-edge, and a section or slit of...

A statistical method of dealing with a series of values where each value is squared, the mean of these squares is calculated, and the square root of that mean is then taken.

A statistical method of dealing with a series of values where each value is squared, the sum of these squares is calculated and the square root of that sum is then taken.

A corrective lens system that is placed near the focal plane of a Newtonian telescope to increase its effective field of view by correcting for coma formed by the telescope's paraboloidal mirror.

A precision positioning device used to produce rotary motion.

A camera system used for microphotography that has a structure, such as a cylinder or surveyor belt, to rotate the documents to be recorded. The image is fixed relative to film motion and exposure is...

A structured light device using a rapidly rotating laser to project a beam of light that appears to the human eye as a continuous circle; used as a reference marker on walls or landscape for...

A disc composed of a series of holographic optical elements that diffract light at various angles. When spinning, a raster scan may be generated.

Developed for use in military reconnaissance systems, it consists of a polygonal mirror, drive motor, interface between motor and mirror, and control electronics. Also used in broadband video...

A camera, with a rotating prism, that is capable of forming multiple exposures on a constantly moving strip of film.

A circular optical wedge (prism of small refracting angle) mounted to be rotated in the path of light rays to divert the line of sight to a restricted degree.

Ability of a laser to resist variations in output power caused when it is slowly rotated about its optical or symmetrical axis.

One of the types of change in the energy levels of molecules or atoms in a laser that can result in lasing action. Because the energy levels between rotational states are small, such lasing action is...

A very fine powdered ferric oxide used in polishing lenses.

A term used to describe a very coarse grinding process.

The circle that contains the slit, grating and primary astigmatic focus of a concave diffraction grating.

In spectroscopy, the false images arranged symmetrically on both sides of the true line and caused by irregularities in the ruling of diffraction gratings.

The mounting of a concave diffraction grating and a plate holder at the ends of a rigid bar. The ends follow separate straight tracks that intersect perpendicular to each other. The slit is located...

RTSP, or real-time streaming protocol, is a network control protocol designed for controlling streaming media servers. It is used for establishing and controlling media sessions between endpoints....

A type of scratch.

The optically pumped, solid-state laser that uses sapphire as the host lattice and chromium as the active ion. The emission takes place in the red portion of the spectrum.

Bearing alternate ridges and grooves; corrugated. Said of some optical surfaces.