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prism
prism P0567100 (prĭz′əm)n.1. A solid figure whose bases or ends have the same size and shape and are parallel to one another, and each of whose sides is a parallelogram.2. A transparent body of this form, often of glass and usually with triangular ends, used for separating white light passed through it into a spectrum or for reflecting beams of light.3. A cut-glass object, such as a pendant of a chandelier.4. A crystal form consisting of three or more similar faces parallel to a single axis.5. A medium that misrepresents whatever is seen through it.
[Late Latin prīsma, from Greek prīsma, thing sawed off, prism, from prīzein, to saw, variant of prīein.]prism (ˈprɪzəm) n1. (General Physics) a transparent polygonal solid, often having triangular ends and rectangular sides, for dispersing light into a spectrum or for reflecting and deviating light. They are used in spectroscopes, binoculars, periscopes, etc2. (General Physics) a form of crystal with faces parallel to the vertical axis3. (Mathematics) maths a polyhedron having parallel, polygonal, and congruent bases and sides that are parallelograms[C16: from Medieval Latin prisma, from Greek: something shaped by sawing, from prizein to saw]prism (ˈprɪz əm)
n. 1. Optics. a transparent solid body, often having triangular bases, used for dispersing light into a spectrum or for reflecting rays of light. 2. Geom. a solid having bases or ends that are parallel, congruent polygons and sides that are parallelograms. 3. Crystall. a form having faces parallel to the vertical axis and intersecting the horizontal axes. [1560–70; < Late Latin prīsma < Greek prîsma literally, something sawed, akin to prizein to saw, prístēs sawyer] prism (prĭz′əm)1. A geometric solid whose bases are congruent polygons lying in parallel planes and whose sides are parallelograms.2. A solid of this type, often made of glass with triangular ends, used to disperse light and break it up into a spectrum.prismA transparent, solid object, with at least two plane faces, that bends a light beam and splits it into its component colors.Thesaurus| Noun | 1. |  prism - a polyhedron with two congruent and parallel faces (the bases) and whose lateral faces are parallelogramspolyhedron - a solid figure bounded by plane polygons or facesparallelepiped, parallelepipedon, parallelopiped, parallelopipedon - a prism whose bases are parallelogramsquadrangular prism - a prism whose bases are quadranglestriangular prism - a prism whose bases are triangles | | 2. |  prism - optical device having a triangular shape and made of glass or quartz; used to deviate a beam or invert an imageoptical prismbiprism - an optical device for obtaining interference fringeserecting prism - a right-angled optical prism used to turn an inverted image uprightoptical device - a device for producing or controlling lightprism spectroscope, spectroscope - an optical instrument for spectrographic analysistelescope, scope - a magnifier of images of distant objects |
Translationsprism (ˈprizm) noun1. a solid figure whose sides are parallel and whose two ends are the same in shape and size. 棱柱 棱柱2. a glass object of this shape, usually with triangular ends, which breaks up a beam of white light into the colours of the rainbow. 棱鏡 棱镜prisˈmatic (-ˈma-) adjective 棱柱形的 棱柱形的
IdiomsSeeprunes and prismsprism
prism, in optics, a piece of translucent glass or crystal used to form a spectrumspectrum,
arrangement or display of light or other form of radiation separated according to wavelength, frequency, energy, or some other property. Beams of charged particles can be separated into a spectrum according to mass in a mass spectrometer (see mass spectrograph).
..... Click the link for more information. of light separated according to colors. Its cross section is usually triangular. The light becomes separated because different wavelengths or frequencies are refracted (bent) by different amounts as they enter the prism obliquely and again as they leave it (see refractionrefraction,
in physics, deflection of a wave on passing obliquely from one transparent medium into a second medium in which its speed is different, as the passage of a light ray from air into glass.
..... Click the link for more information. ). The shorter wavelengths, toward the blue or violet end of the spectrum, are refracted by the greatest amount; the longer wavelengths, toward the red end, are refracted the least. The Nicol prismNicol prism
, optical device invented (1828) by William Nicol of Edinburgh. It consists essentially of a crystal of calcite, or Iceland spar, that is cut at an angle into two equal pieces and joined together again with Canada balsam.
..... Click the link for more information. is a special type of prism made of calcite; it is used for polarization of lightpolarization of light,
orientation of the vibration pattern of light waves in a singular plane. Characteristics of Polarization
Polarization is a phenomenon peculiar to transverse waves, i.e.
..... Click the link for more information. .PrismA geometric solid with regular polygons at its ends and parallelograms on its sides connecting the ends.Prism a polyhedron in which two of the faces are n-gons (the bases of the prism) and the remaining n faces (the lateral faces) are parallelograms. The bases of a prism are congruent and lie in parallel planes.  Figure 1
A prism is called a right prism if the lateral edges are perpendicular to the bases. A right prism is regular if each base is a regular polygon. Prisms can be triangular, quadrangular, and so on, depending on whether the bases are triangles, quadrilaterals, and so on. Figure 1 illustrates a hexagonal prism (the one on the left is also a right prism). The volume of a prism is equal to the product of the base and the altitude (the distance between the bases). See also. prism[′priz·əm] (crystallography) A crystal which has three, four, six, eight, or twelve faces, with the face intersection edges parallel, and which is open only at the two ends of the axis parallel to the intersection edges. (geology) A long, narrow, wedge-shaped sedimentary body with a width-thickness ratio greater than 5 to 1 but less than 50 to 1. (mathematics) A polyhedron with two parallel, congruent faces and all other faces parallelograms. (optics) An optical system consisting of two or more usually plane surfaces of a transparent solid or embedded liquid at an angle with each other. Also known as optical prism. prism1. a transparent polygonal solid, often having triangular ends and rectangular sides, for dispersing light into a spectrum or for reflecting and deviating light. They are used in spectroscopes, binoculars, periscopes, etc. 2. a form of crystal with faces parallel to the vertical axis 3. Maths a polyhedron having parallel, polygonal, and congruent bases and sides that are parallelograms PRISMA distributed logic language.
["PRISM: A Parallel Inference System for Problem Solving",S. Kasif et al, Proc 1983 Logic Prog Workshop, pp. 123-152].PRISM(1) (PhotoRefractive Information Storage Materials Consortium) A collaboration of IBM, Stanford University, GTE, Hughes Research Labs, Optitek, SRI International and Rockwell Science Center that is funded by the U.S. government's Advanced Research Projects Agency for the purpose of researching holographic storage.
(2) (PRogrammable Integrated Scripts for Mirror) The programming language for the Mirror communications programs.
(3) See PR/SM.prism
prism [priz″әm] a solid of glass, plastic, or a similar substance with a triangular or polygonal cross section, which splits up a ray of light into its constituent colors and turns or deflects light rays toward its base. Prisms are used to correct deviations of the eyes, since they alter the apparent situation of objects. A, Light is deviated by the prism toward its base. B, The observer views an object through the prism and the object appears displaced toward its apex. From Stein et al., 2000.prism (prizm), A transparent solid with sides that converge at an angle, which deflects a ray of light toward the thickest portion (the base) and splits white light into its component colors; in spectacles, a prism corrects ocular muscle imbalance. [G. prisma] PRISM Platelet Receptor Inhibition in ischaemic Syndrome Management. A trial that compared a composite end point (death, acute MI and refractory ischaemia at 48 hours) in patients with unstable angina who were already receiving aspirin, and managed with either heparin or tirofiban, a nonpeptide inhibitor of platelet glycoprotein IIb/IIIa receptor.
Results
Tirofibran reduced mortality, but not acute MIs or refractory ischaemia.PRISM Cardiology A clinical trial–Platelet Receptor Inhibition in Ischemic Syndrome Management which compared the composite end point–Death, MI, and refractory ischemia at 48 hrs of Pts with unstable angina–who were already receiving aspirin, who were managed with either heparin–H or tirofiban–T–
a specific, nonpeptide inhibitor of platelet gpIIb/IIIa receptor. See Tirofiban. prism (prizm) A transparent solid, with sides that converge at an angle, that deflects a ray of light toward the thickest portion (the base) and splits white light into its component colors; in spectacles, a prism corrects ocular muscle imbalance. [G. prisma]prism A transparent body (e.g. plastic, glass) bounded by two inclined plane surfaces, which intersect in a straight line called the apex, and form an angle called the prism angle. The face opposite the apex is called the base. It is an optical element used to deviate light (towards the base of the prism). The angle of deviation d of a prism in air is given by the following formulad = i + i′ − awhere i is the angle of incidence, i′ the angle of emergence and a the prism angle (Fig. P15). See vergence adaptation; base setting; prism dioptre; prism power; minimum deviation of a prism; ophthalmic prism; recumbent spectacles; spectroscope.
achromatic prism A prism that deviates light without dispersion. It consists of two prisms, usually one of crown glass and the other of flint, of equal angular dispersions and mounted so that the apex of one is against the base of the other.
prism adaptation See vergence adaptation; prism adaptation test.
aligning prism See associated heterophoria.
prism ballast lens See ballast.
prism bar Clinical device consisting of a series of prisms of increasing strengths arranged in a convenient mount for rapid positioning in front of an eye. It can be used with the cover test or even to measure fusional responses when determining the zone of clear, single, binocular vision if rotary prisms are not available.
base-in prism; base-out prism See base setting.
bi-prism See Fresnel's bi-prism.
prism binoculars See binoculars.
compensating prism See associated heterophoria; relieving prism.
prism
cover test See cover test.
Crete's p . See rotary prism.
prism dioptre See prism dioptre.
dissociating prism A prism which, when placed in front of an eye, produces dissociation.
double prism See Fresnel's bi-prism.
double prism test See double prism test.
Dove prism An isosceles reflecting prism used to invert the image in an optical system. Light enters one side, is then refracted onto the base surface where it is internally reflected and refracted again through the other side.
erecting prism A prism designed to invert an image in an optical system with no change of size or shape. Examples: Dove prism, Porro prism. Syn. inverting prism. See erector.
Fresnel Press-On prism A trade name for a thin disc of transparent plastic consisting of one flat surface which can adhere to a clean lens surface when pressed in place, and another surface on which are incorporated small prismatic elements laid parallel to one another. Large optical effects can thus be provided in a much thinner and lighter form. These Press-On Fresnel prisms can be cut to any desired shape and are used commonly in orthoptics treatment. See Fresnel lens; orthoptics.
Herschel prism See rotary prism.
induced prism Prismatic effect created when the patient's visual axis does not pass through the optical centre of an ophthalmic lens. The amount of prism power is given by Prentice's law. See correction induced convergence; Prentice's law.
inverting p . See prism, erecting.
lacrimal prism See tear meniscus.
minimum deviation of a prism The deviation of light rays from their original path is minimum when light passes symmetrically through a prism so that the incident and emergent angles are equal (Fig. P15). See angle of deviation; prism.
Nicol prism An optical device for producing a beam of plane polarized light. It is made from a piece of calcite crystal cut diagonally in half with the two halves cemented together. Incident light is split into ordinary and extraordinary linearly polarized rays in the prism: the ordinary ray reaches the interface and is totally reflected, while the extraordinary ray is transmitted (Fig. P16). See analyser; birefringence; polarizer.
ophthalmic prism A prism used in the correction or in the measurement of a deviation of the eyes. The power of such a prism is usually only a few prism dioptres. The power of a thin prism in air, represented by the angle of deviation d, is given by the approximate formulad = (n − 1) awhere n is the index of refraction of the prism and a the prism angle. Example: if the prism angle is equal to 10º and the index of refraction of the prism is 1.523, the deviation will be equal to 5.23º or 9.12 Χ. (Fig. P17). See prism dioptre; prism power.
penta prism See Fig. P18.
polarizing prism A prism made from doubly refracting material. Example: quartz. See analyzer; polarized light; polarizer.
Porro prism A combination prism consisting of two 90º totally reflecting prisms arranged at right angles to each other. It is used in optical systems, such as binoculars to invert the image and provide a shorter displacement. It is the most common erecting prism.
prism power See prism power.
reflecting prism A prism in which light is internally reflected at one or more of the plane surfaces before emerging. This happens when the angle of incidence at the surface is greater than the critical angle (Fig. P18). Syn. total reflecting prism. See total reflection.
prism reflex test See Krimsky's method.
relieving prism An ophthalmic prism prescribed to relieve symptoms caused by an uncompensated heterophoria. Syn. compensating prism.
Risley prism See rotary prism.
rotary prism A pair of identical thin prisms mounted one in front of the other, so that they can be rotated by equal amounts in opposite directions to give a resultant power in a single meridian. The power can vary from zero when the apex of one prism coincides with the base of the other, to the sum of the powers of the two prisms when the apices coincide. The Risley prism is a very common type of rotary prism. It is used to determine the limits of the zone of clear, single, binocular vision and also in some stereoscopes (e.g. variable prism stereoscope). Other types of rotary prisms are those of Crete and Herschel. Syn. variable prism. See base setting; variable prism stereoscope.
tear prism See tear meniscus.
total reflecting prism See reflecting prism.
version prism's See yoke prisms.
Wollaston prism Two right-angled prisms of equal angle made of a double refracting crystal such as quartz or calcite cemented together by their hypotenuse faces to form a rectangular unit. The optical axis of the crystal in one prism is perpendicular to that in the other prism and both axes are also perpendicular to the direction of the incident light. A beam of unpolarized light incident on a Wollaston prism will emerge as two diverging beams which are oppositely polarized and almost free of dispersion. This prism is used in some types of keratometers (e.g. Javal-Schiotz). Syn. Wollaston polarizer.
yoke prism's Two prisms, one in front of each eye, of equal deviation and direction (e.g. 2 ΧBU, OU). The apparent view moves towards the apex of the prisms. These are sometimes prescribed in the management of nystagmus, in visual training, for the bedridden (BD prisms) and in some cases of physical disability. (Fig. P19) Note: also spelt yoked prisms. Syn. version prisms. " > Fig. P15 Prism (a, prism angle; i, angle of incidence = i′, angle of emergence; Vm, angle of minimum deviation)" > Fig. P16 Nicol prism (O, ordinary ray; E, extraordinary ray)" > Fig. P17 A line of stars seen through a prism base down" > Fig. P18 Examples of reflecting prisms (A, penta prism, with surfaces C coated with silver or aluminium; B and C, in which the surfaces reflect light by total internal reflection)" > Fig. P19 Yoke prisms
| Table P10 Approximate deviation of thin ophthalmic prisms of various apical angles and of two different refractive indices | | | deviation | | apical angle in degrees (º) | | spectacle crown glass
(n 5 1.523) | | extra dense flint glass
(n 5 1.70) | | | degrees (º) | | Χ | | degrees (º) | | Χ | | 1 | | 0.52 | | 0.91 | | 0.70 | | 1.22 | | 2 | | 1.05 | | 1.84 | | 1.40 | | 2.45 | | 3 | | 1.57 | | 2.75 | | 2.10 | | 3.67 | | 4 | | 2.09 | | 3.66 | | 2.80 | | 4.90 | | 5 | | 2.61 | | 4.57 | | 3.50 | | 6.12 | | 6 | | 3.14 | | 5.49 | | 4.20 | | 7.35 | | 7 | | 3.66 | | 6.40 | | 4.90 | | 8.57 | | 8 | | 4.18 | | 7.31 | | 5.60 | | 9.80 | | 9 | | 4.71 | | 8.24 | | 6.30 | | 11.02 | | 10 | | 5.23 | | 9.15 | | 7.00 | | 12.25 | | 11 | | 5.75 | | 10.06 | | 7.70 | | 13.47 | | 12 | | 6.28 | | 10.99 | | 8.40 | | 14.70 |
PRISM
| Acronym | Definition |
|---|
| PRISM➣Preemptive Reconnaissance and Identification Security Mainframe | | PRISM➣Processor Reconfiguration Through Instruction Set Metamorphosis | | PRISM➣Publishers Requirements for Industry Standard Metadata | | PRISM➣Photo Refractive Information Storage Material | | PRISM➣Primitive Instruction Set Machine | | PRISM➣Panchromatic Remote-Sensing Instrument for Stereo Mapping (radiometer) | | PRISM➣Partnership for Research Integrity in Science & Medicine | | PRISM➣Parameter-Elevation Regressions on Independent Slopes Model (climatology) | | PRISM➣Performance and Registration Information Systems Management | | PRISM➣Pediatric Risk of Mortality | | PRISM➣Publishing Requirements for Industry Standard Metadata | | PRISM➣Partnership for Research in Spatial Modeling | | PRISM➣Purchase Request Information System (various US government agencies) | | PRISM➣Public Retirement Information Systems Management | | PRISM➣Portable Reusable Integrated Software Modules | | PRISM➣Portable, Reusable, Integrated Software Modules | | PRISM➣Pico-Satellite for Remote-Sensing and Innovative Space Missions (satellite; University of Tokyo; Japan) | | PRISM➣Program of Resources, Information and Support for Mothers (BioMed Center) | | PRISM➣PRInceton Scorekeeping Method | | PRISM➣Parallel Reduced Instruction Set Multiprocessing | | PRISM➣Parameterized Real-Time Ionospheric Specification Model | | PRISM➣Photorefractive Information Storage Materials | | PRISM➣Passive Radar Identification System | | PRISM➣Process Industries Safety Management | | PRISM➣Programmed Integrated System Maintenance | | PRISM➣Power Reactor Inherently Safe Module | | PRISM➣Photo Reconnaissance Intelligence Strike Module | | PRISM➣Pacific Roundtable on Industry, Society and Management (University of British Columbia; Vancouver, BC, Canada) | | PRISM➣Protective Response Interactive Services Management (emergency notification system) | | PRISM➣Property Registration Information System Module | | PRISM➣Programmed Research Information System at Michigan (University of Michigan) | | PRISM➣Paranormal Researchers in Southeast Michigan | | PRISM➣Planning Tool for Resource Integration, Synchronization and Management | | PRISM➣Project Risk Identification, Selection, and Management | | PRISM➣Project to Redesign Information Systems Management | | PRISM➣Programming Remediation and Intervention for Students in Mathematics (Canada) | | PRISM➣Partnership for Research in Information Systems Management | | PRISM➣Pharmacy Related Information Storage Method | | PRISM➣Preservice Research Institute for Science and Mathematics | | PRISM➣Personnel Requirements Information System Methodology | | PRISM➣Project to Revolutionise Information Systems and Management At UCT (University of Cape Town, South Africa) | | PRISM➣Prioritized Requirements, Impacts & Schedule Milestones | | PRISM➣Personnel Record Information Systems for Management (UK) | | PRISM➣Program for Information Storage and Management | | PRISM➣Performance of Routine Information System Management | | PRISM➣Prisoner Rights Information System of Maryland, Inc. | | PRISM➣Performance Resource Information System for the Millennium | | PRISM➣Provider Requirements Integrated Specialty Model (military healthcare system) | | PRISM➣Plant Risk-Informed Systems Model (software; Engineering Planning and Management) | | PRISM➣Promotion Recommendation & In-Board Support MIS (Management Information System) | | PRISM➣Project Resources Information System for Management (USACE) | | PRISM➣Personnel Resource Information System for Managers | | PRISM➣Program for Integrated Sonar Modeling | | PRISM➣Program Reliability Information System for Maintenance | | PRISM➣Pride Raising Awareness Involvement Support Mentoring (Arkansas) | | PRISM➣Pointed Rotating Imaging Spectroscopy Mission | | PRISM➣Passport Records Information System Management (US Department of State) |
prism
Synonyms for prismnoun a polyhedron with two congruent and parallel faces (the bases) and whose lateral faces are parallelogramsRelated Words- polyhedron
- parallelepiped
- parallelepipedon
- parallelopiped
- parallelopipedon
- quadrangular prism
- triangular prism
noun optical device having a triangular shape and made of glass or quartzSynonymsRelated Words- biprism
- erecting prism
- optical device
- prism spectroscope
- spectroscope
- telescope
- scope
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