8,738 terms
Photonics Dictionary
Search 8,700+ definitions in the Photonics Dictionary—your authoritative source for terms in optics, lasers, imaging, fiber optics, and related technologies.
sliding wedge -> measuring wedgeA wedge in a rangefinder or heightfinder used to displace the image produced by one telescope so that it coincides with that produced by the other telescope, thus affording a measurement of the...
slitAn aperture, usually rectangular in shape, with a large length-to-width ratio, and a fixed or adjustable shape through which radiation enters or leaves an instrument. The aperture is generally small...
slit-width errorThe error inherent in spectral energy or spectrophotometric quantity due to the finite dimension of the entrance and exit slits.
SLMsingle longitudinal mode; spatial light modulator
SLOswept local oscillator
slot modulatorIn photonics, a slot modulator refers to a type of optical modulator that operates based on the principle of modifying the optical properties of a slot waveguide.
A slot modulator is an optical...
slow axis -> fast axisIn a birefringent material, the index of refraction varies with the direction of vibration of a lightwave. That direction having a low refractive index is the fast axis; at right angles to it is the...
slow-scan televisionA television system that uses a slow rate of horizontal scanning to increase its reproduction and transmittance accuracy of printed matter, photographs and illustrations.
SLPsingle linear polarization
SLRsingle-lens reflex
SLSselective laser sintering; strained-layer superlattice
SLTsatellite laser tracking
slurryThe name of the mixture of liquid and grinding or polishing compounds used in processing optical materials.
SMsingle mode
SMA connectorThe fiber optic connector developed and manufactured by Amphenol Fiber Optic Products.
small-angle x-ray scatteringThe investigation of microstructures by an instrument that generates a narrow, highly collimated beam of x-rays.
smart bombA bomb guided to its target by some form of electro-optical system.
smart citiesSmart cities are urban environments that use information and communication technologies (ICT) and data-driven solutions to optimize city operations and services across various domains such as...
smart microscopySmart microscopy refers to the integration of advanced technologies, such as artificial intelligence (AI), automation, and machine learning, into conventional microscopy techniques to enhance imaging...
smart pixel arrayAn array of active optical devices (modulators, laser diodes and/or detectors), each of whose electrical inputs or outputs are directly connected to electronic logic circuits, which also are a part...
smart skinStructural surfaces that incorporate an embedded sensor network capable of detecting flaws within the structure.
SMBussystem management bus
SMDsurface-mount device
SMDSswitched multimegabit data service
SMESociety of Manufacturing Engineers
smearA lack of resolution in a television image as a result of smear ghosts or an insufficiently high video-frequency response. The distortion appears to be extended horizontally and blurred.
smear camera -> streak cameraA streak camera is a specialized instrument used to capture and analyze ultrafast phenomena, such as extremely short pulses of light or rapidly changing events. Unlike traditional cameras that...
smear ghostA false image in television that follows the desired image so closely that it appears to be smeared.
smectic phaseA form of liquid crystal in which flow does not take place in the usual manner. When examined with polarized light, the substance often forms drops that display a series of fine lines. X-ray...
SMILEspherical microintegrated lens
Smith-Baker microscopeA transmission interference microscope that produces interference patterns of a sample by using birefringent plates that split a polarized beam of light into ordinary and extraordinary rays, then...
SMPTESociety of Motion Picture and Television Engineers
SMSRside mode suppression ratio
SMTsurface-mount technology
Snell's law of refractionThe incident ray, the normal to the refracting surface at the point of incidence of the ray at the surface, and the refracted ray all lie in a single plane. The ratio of the sine of the angle between...
Snellen letterThe letter form used on visual performance test charts. The overall letter height is equal to five times the thickness of individual strokes. Normal 20/20 vision is represented by the ability to...
sniperscopeA high-power riflescope specifically intended for sighting and shooting distant targets.
snooperscopeAn instrument used for viewing in low levels of illumination by means of infrared radiation. A high-aperture lens forms an image of distant objects on the photocathode of an infrared-sensitive image...
SNRsignal-to-noise ratio
SOAsemiconductor optical amplifier
SoCsystem on chip
sodium light sourceAn electric discharge lamp in which the conducting vapor is that of metallic sodium instead of the usual mercury. It emits a strong yellow light of a single wavelength.
soft coatingA term describing an antireflection coating that may be applied to optics that cannot tolerate the high temperatures usually required for normal "hard'' coatings. Such coatings lack durability...
soft mold blockingBlocking by means of a pitch ring, pitch button or a totally pitched block. Pitch, containing a soft filter, may be used between the optical components to bar lateral movement.
soft radiationTerm applied to radiation composed of particles or photons that will not easily penetrate a material because of their low energy levels.
soft-focus filterA filter that creates spherical aberration resulting in an image with a soft outline.
soft-focus lensA lens that exhibits spherical aberration when used at large aperture settings, and that forms an image with a slightly blurred outline.
SOGsilicone on glass
SOHOsolar heliosphere observatory
SOIsilicon on insulator
Photonics Dictionary