Search
Menu
Photonics Marketplace
414 terms

Photonics Dictionary: R

Clear All Filters xR x
radiative recombination -> band-to-band photoluminescence
The emission of a photon by the return of an excited carrier from the conduction band to the valence band of a semiconductor along a radiative recombination path. The resulting photoluminescence...
radio astronomy
The detection and analysis of naturally formed extraterrestrial electromagnetic radiation within the radio frequency range of the spectrum.
radio frequency
The frequency range for radio and television transmission.
radio telescope
An instrument designed to collect naturally formed extraterrestrial electromagnetic radiation within the radio frequency range of the spectrum in amounts sufficient to be measured.
radio-frequency discharge laser
A gas laser in which the electrodes are mounted perpendicular to the optical resonator.
radio-frequency light source
A very uncommon lamp in which a tungsten electrode is heated to incandescence by a radio-frequency electrical current.
radio-frequency linear accelerator
A device used to accelerate the electrons in a free-electron laser by channeling microwave energy into waveguide cavity assemblies.
radioactive tracer
A radioactive element that is placed or injected into a system to obtain an autoradiogram of the system. It is used in a number of fields where standard methods of internal imaging, for example,...
radioactivity detector
An instrument used to detect radioactive materials: alpha particles or helium nuclei; beta particles or free electrons; and gamma rays, which are x-rays of very short wavelength. They may be detected...
radioautograph
The photographic image of a thin specimen having a radioactive isotope that, formed through contact between the specimen and a photographic plate, displays the distribution of the radioactive...
radiograph
An x-ray or radium photograph illustrating the nonuniform density of the structure that the rays penetrate.
radiographic amplifier screen
A solid-state panel of the photoconductor-electroluminescent type. The photoconductive layer, sensitive to x-rays, is coated by the electroluminescent, which gives the visible image. When the former...
radiography
A photographic process using x-ray radiation or the g-rays of radioactive materials.
radiology
The study of radioactive substances and high-energy radiations such as x-rays and g-rays.
radioluminescence
Luminescence produced by the bombardment of radiant energy such as x-rays, radioactive waves or alpha particles.
radiometallography
The analysis, by x-rays, of the crystalline structure and other properties of metals and alloys.
radiometer
A device used to measure the intensity of radiant energy.
radiopaque
Incapable of being penetrated by any form of radiation.
radioparent
Capable of being penetrated by some form of radiation.
radiophotograph
A photograph transmitted by radio waves.
radiophotography
The transmission of photographic images or pictures by radio waves.
radiophotoluminescence
The luminescence displayed when particular minerals are irradiated with β-rays and g-rays, after being exposed to nuclear radiation.
radius tool
A metal device of convex or concave curvature to which lens castings or semifinished lenses are cemented with only their edges in contact with the device.
radiuscope
A microscope to which a beamsplitter and illuminated reticle have been added that is used to measure contact lenses.
radix
Total number of characters available to each position of a digital numeric system.
RAE
resistive anode encoder
RAI
random access integration
rail -> optical bench
A support for optical parts comprising a solid bed that permits precise longitudinal movement of one component relative to the others, and a number of sliders equipped with holders for lenses, lamps,...
rainbow hologram
Essentially, a hologram of a hologram, in which the first-generation hologram is masked with a narrow slit. During image reconstruction, the slit operates as the exit pupil in image space. The...
RAM
random access memory
Raman absorption
The absorption of part of the photon energy by a molecule through which there is a slight energy change and the energy balance moves on.
Raman effect
When light is transmitted through matter, part of the light is scattered in random directions. A small part of the scattered light has frequencies removed from the frequency of the incident beam by...
Raman fiber probe
A flexible fiber cable with a small diameter that transports light from the excitation laser to the target. Used in Raman spectroscopy, the probe is capable of obtaining high-quality data at high...
Raman laser -> Raman effect
When light is transmitted through matter, part of the light is scattered in random directions. A small part of the scattered light has frequencies removed from the frequency of the incident beam by...
Raman scattering -> Raman effect
When light is transmitted through matter, part of the light is scattered in random directions. A small part of the scattered light has frequencies removed from the frequency of the incident beam by...
Raman shifter
A device that changes the frequency of light by inducing the Raman effect on a beam passing through it.
Raman spectroscopy
Raman spectroscopy is a technique used in analytical chemistry and physics to study vibrational, rotational, and other low-frequency modes in a system. Named after the Indian physicist Sir C.V. Raman...
Ramsden circle -> exit pupil
In a lens or other optical system, the image of the aperture stop as seen from image space.
Ramsden eyepiece
An eyepiece consisting of two planoconvex lenses of the same focal length, with facing convex surfaces.
random access multiphoton microscopy
Also known as RAMP microscopy, random access multiphoton microscopy is a microscopic technique that uses multiple acousto-optic modulators to enable faster and addressable scanning of 3D cellular...
random noise
Essentially, noise that cannot be predicted. Therefore, even if the magnitude of sound or oscillation in a system is known at a given moment, random noise can change in a short time.
randomized fiber optic cable
Fiber optic cable in which the arrangement of fibers within the bundle has been made random so that output light will be uniformly distributed and not relay the image of the light source at the input...
range axis
The third dimension (depth or Z-axis) in an imaging system.
rangefinder
1. An optical distance finder that depends on triangulation of two convergent beams on an object from disparate view points. 2. A device that depends on the measurement of time of wave travel from an...
rapid access system
A photographic camera and processing system used to form a usable record of the subject in a short time, usually a few seconds, for immediate analysis.
rapid rectilinear lens
A double meniscus system in which two achromatized meniscus lenses are arranged symmetrically on either side of the aperture stop, reducing or eliminating distortion, coma and lateral color.
rare earth dopants
Rare earth dopants refer to elements from the lanthanide series, also known as rare earth elements, that are intentionally introduced into the crystal lattice of a material to modify its properties....
rare gas halide laser -> excimer laser
An excimer laser is a type of ultraviolet laser that emits short pulses of light in the ultraviolet spectrum. The term excimer is derived from excited dimer, reflecting the nature of the gain medium...
rare-earth doped fiber
An optical fiber in which ions of a rare-earth element, such as neodymium, erbium or holmium, have been incorporated into the glass core matrix, yielding high absorption with low loss in the visible...
rare-earth elements
Rare-earth elements (REEs) are a group of seventeen chemical elements found in the Earth's crust, characterized by their unique properties and scarcity relative to other elements. Despite their name,...

Photonics DictionaryR

We use cookies to improve user experience and analyze our website traffic as stated in our Privacy Policy. By using this website, you agree to the use of cookies unless you have disabled them.