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Meadowlark Optics - Building system MR 7/23

2,296 terms

Photonics Dictionary

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star testing

The visual examination by a trained observer of the image of a point source. Any coloring or departure from the Airy disc rings indicates the presence of aberrations in the lens forming that image.

staring sensor array -> mosaic detector array

A group of photosensors arranged in a grid-like pattern covering the entire field of view, enabling them to record it all at once (as a camera records an image on film) rather than by scanning parts...

starting voltage

In a laser, the voltage necessary to initiate electrical discharge, somewhat higher than that needed to sustain it.

STC

Science & Technology Center

stellar interferometer -> Michelson stellar interferometer

An interferometer constructed to be positioned on a telescope to measure the angular separation of the components of double stars.

STEM

scanning transmission electron microscope

step tablets

In sensitometric testing, a series of areas progressing by equal density steps (usually the increments between steps are equal to the logarithm of the square root of two). They are commonly used in...

step-and-repeat camera

A type of camera that has scales or other arrangements by which successive exposures can be lined up and equally spaced on a sheet of film. It is used in the preparation of microfiche copies of...

stereocomparator

1. A stereoscope that has adjustable scales to allow the determination of distances and dimensions from stereoscopic photographs. 2. A device used to view pictures of the same section of the night...

stick marks

The fine scratches formed when, in hand centering, the forked stick used to move the lens on the chuck marks the rotating lens surface.

stitching

The process of creating a large, panoramic image by aligning and joining a set of smaller images. Image processing is used to obscure the edges between the smaller images, producing a seamless...

STM

scanning tunneling microscope; synchronous transfer mode

Stokes line

A line of the Raman spectrum that fulfills Stokes' law because it possesses a wavelength that is greater than the radiation that stimulated the luminescence of the source.

Stokes' law

Relative to radiation wavelength, the law that states that the wavelength of luminescence stimulated by radiation always surpasses that of the stimulating radiation.

strain viewer

A viewer that uses the transmittance of polarized light through glass or a similar medium to examine strained regions. See polariscope.

strobotron

A specified cold-cathode gas tube used to apply a short-duration, high-power arc for a stroboscope.

structural color

Structural color refers to coloration in materials that is not caused by pigments or dyes but is instead a result of the physical structure of the material. In structural color, the interaction of...

STS

stimulated thermal scattering

substage condenser

In a microscope, the optical assembly that focuses light on the specimen and into the objective.

subtractive colors

Cyan, magenta and yellow. They are called subtractive because they each subtract one color by absorbtion and reflect the two others of the red, green, blue color primaries. Cyan absorbs red, magenta...

sun synchronous

Characterizes an Earth-orbiting satellite whose orbit plane is near polar and positioned at an altitude that allows it to pass over every spot on the Earth at identical local sun time twice a day.

supercontinuum

Supercontinuum refers to a broad spectrum of light that spans a wide range of wavelengths, typically from the visible to the near-infrared or even mid-infrared regions of the electromagnetic...

superreflector

A reflector having a surface that has been superpolished to reduce residual sleeks and scratches and microroughness so that its scatter coefficient is low. Its surface is said to have a low-scatter...

superresolution

Superresolution refers to the enhancement or improvement of the spatial resolution beyond the conventional limits imposed by the diffraction of light. In the context of imaging, it is a set of...

supplementary lens

A meniscus that is often fitted before a camera lens to permit focusing on near objects.

surface analysis by laser ionization

(SALI) A type of spectroscopy in which neutral atoms or molecules are ionized by an excimer laser beam and then measured by a time-of-flight mass spectrometer.

surface electromagnetic waves

Waves that propagate along the interface between two different media without radiation with exponentially decaying evanescent fields on both sides.

surface quality

The specification of allowable flaws in a surface by comparison to reference standards of quality. Two graded sets of surface quality standards are employed. The first denotes defects of a long...

surface quality standards

The standards of MIL-O-13830 set by the US government relative to tolerable surface scratches and other such defects in an optical system. A series of standard glass plates that have been...

surround

A term that describes both the color and intensity of the immediate environment of the object or image being viewed.

surveying instruments

Instruments used for measuring angles and occasionally lengths on the ground. The principal surveying instruments are the level, the stadia telescope, the transit and the theodolite. Laser...

surveyor's level

A small telescope mounted on a tripod and free to rotate about a vertical axis. A spirit level is mounted over the telescope and adjusted so that when the bubble is central, the telescope axis is...

swept source optical coherence tomography

Swept-source optical coherence tomography is an imaging technique used in medical diagnostics, particularly in ophthalmology, to visualize and analyze the internal structures of biological tissues,...

swing

The length of the oscillation of a grinding or polishing lap.

SXT

solar-A soft x-ray telescope

sync

Abbreviation of "synchronization.'' In television, the timing signals used to drive the scanning process. Horizontal sync triggers the retracing of the raster line beginning at the left-hand...

synchrotron

A synchrotron is a type of particle accelerator that uses magnetic fields to steer charged particles, typically electrons or positrons, in a closed, circular or elliptical path. The name synchrotron...

synthetic interferometric image

An imaging technique in which an object moving through an interference field formed in space scatters light and is spatially recorded on a photographic film as a hologram. If the interference field...

t number

The equivalent f number of a fictitious lens that has a circular opening and 100 percent transmittance, which would give the same central illumination as the lens being considered: where...

T stop -> t number

The equivalent f number of a fictitious lens that has a circular opening and 100 percent transmittance, which would give the same central illumination as the lens being considered: where...

Talbot's bands

The series of interference bands that appear in the spectrum when a specified glass plate is inserted into a spectroscope, from the side of the blue portion of the spectrum, so that the plate...

Talbot's law

The law stating that the brightness of an object that is examined through a slotted disc, rotating over a critical frequency, is proportional to the angular aperture divided by the opaque sectors.

target

1. The anode or anticathode of an x-ray tube that emits x-rays when bombarded by electrons. 2. The screen in a television imaging tube that is scanned by an electron beam to determine the...

TDS

time-domain spectroscopy

TEA laser -> transversely excited atmosphere laser

Also known as TEA laser. A coherent optical source with a wide wavelength range in the infrared, visible and ultraviolet that uses an electrical discharge transverse to (across) the optical axis to...

telemeter

1. The term used to describe any of the many instruments used to remotely record physical dimensions, such as strain, temperature or pressure, and transmit this data to a receiving station. 2. A...

telemetry

The science of sensing and measuring information at some remote location and transmitting the data to a convenient location for reading or recording.

telephotometer

An instrument used to measure the luminance (brightness) of a distant object. The object is viewed through a small telescope, and a mirror in the focal plane reflects an internal illuminated surface...

television projection

A television display system in which the television signal is converted to an image that is projected onto either a front or rear projection screen.

television signal

The combination of the audio and visual signals that are transmitted and received at the same time, correlating the scene and sound in a television picture.

Photonics Dictionary