1、Designation: E 175 82 (Reapproved 2005)e1Standard Terminology ofMicroscopy1This standard is issued under the fixed designation E 175; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in parenthese
2、s indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.e1NOTETerms were added editorially in July 2005.Abbe condensersee condenser, Abbe.abe
3、rrationany error that results in image degradation. Sucherrors may be chromatic, spherical, astigmatic, comatic,distortion, or curvature of field; and can result from design orexecution, or both.achromaticliterally, color-free. A lens or prism is said to beachromatic when corrected for two colors. T
4、he remainingcolor seen in an image formed by such a lens is said to besecondary chromatic aberration.achromatic objectivean objective that is corrected chro-matically for two colors, and spherically for one, usually inthe yellow-green part of the spectrum.Airy diskthe image of a bright point object,
5、 as focused by alens system. With monochromatic light, it consists of acentral point of maximum intensity surrounded by alternatecircles of light and darkness caused by the reinforcement andinterference of diffracted rays. The light areas are calledmaxima and the dark areas minima. The distribution
6、of lightfrom the center to the outer areas of the figure wasinvestigated mathematically by Sir GeorgeAiry. The diffrac-tion disk forms a basis for determining the resolving powerof an ideal lens system. The diameter of the disk dependslargely on the aperture of the lens. The diffraction of lightcaus
7、ing the Airy disk is a factor limiting the resolution of awell corrected optical system.analyzeran optical device, capable of producing planepolarized light, used for detecting the state of polarization.angstrm unita unit of linear measure named after A. J.ngstrm. It is 1 3 1010metres; 1 m = 10,000
8、. It isgenerally abbreviated as A. in the United States; elsewhere,it is variously abbreviated , A., A.U., ., or U.angular aperturesee aperture, angular.aperture, angularthe angle between the most divergent raysthat can pass through a lens to form the image of an object.aperture, effectivethe diamet
9、er of the entrance pupil; it isthe apparent diameter of the limiting aperture measured fromthe front.aplanaticcorrected for spherical aberration and coma.apochromatic objectivea lens system whose secondarychromatic aberrations have been substantially reduced. (Seeachromatic).axis, opticalthe line fo
10、rmed by the coinciding principal axesof a series of optical elements comprising an optical system.It is the line passing through the centers of curvature of theoptical surfaces.axis, opticthe direction, or directions in an anisotropiccrystal along which light is not doubly refracted.balsam, Canadaa
11、resin from the balsam fir Abies balsamea.Dissolved in xylene, toluene, or benzene it is used as amountant for permanent microscopical preparations. Itsrefractive index may vary from 1.530 to 1.545 and itssoftening point from room temperature to 100C, theseproperties varying with age and solvent cont
12、ent. If impure itdiscolors with age.Bertrand lenssee lens, Bertrand.bisectrix, acutein biaxial crystals, that principal axis of theellipsoid of indexes which bisects the smaller angle betweenthe optic axes.bisectrix, obtusein biaxial crystals, that principal axis of theellipsoid of indexes which bis
13、ects the larger angle betweenthe optic axes.calcitea doubly refracting mineral used in the manufactureof polarizing prisms. It is uniaxial negative and in thetrigonal diversion of the hexagonal system of crystals. Itsindexes are e = 1.486, v = 1.658; its hardness is 3 on theMohr scale and specific g
14、ravity 2.711.Canada balsamsee balsam, Canada.chromatic aberrationa defect in a lens or lens system as aresult of which the lens possesses different focal lengths forradiation of different wavelengths.collimationthe operation of controlling a beam of radiationso that if the light source were a point,
15、 the light rays wouldbecome parallel. The total bundle of rays diverge as thesource size increases.1This terminology is under the jurisdiction of ASTM Committee E41onLaboratory Apparatus and is the direct responsibility of Subcommittee E41.01 onApparatus.Current edition approved May 1, 2005 Publishe
16、d July 2005. Originally approvedin 1961. Last previous edition approved in 1995 as E 17582(1995).1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United Saa lens aberration occurring in that part of the imagefield that is some distance from the pri
17、ncipal axis of thesystem. It results from different magnification in the variouslens zones. Extra-axial object points appear as short comet-like images with the brighter small head toward the center ofthe field (positive coma) or away from the center (negativecoma).compensating eyepiecesthose design
18、ed for use with objec-tives such as apochromats in order to correct chromaticaberration.condenser or condenser lensa term applied to lenses ormirrors designed to collect, control, and concentrate radia-tion in an illumination system.condenser, Abbeoriginally a two-lens substage condensercombination
19、designed by Ernst Abbe. It lacks chromaticcorrection though designed for a minimum of sphericalaberration and has only a very low-angle aplanatic cone. Itmay be rated with a numerical aperture as high as 1.3.condenser, darkfielda condenser forming a hollow cone oflight with its apex (or focal point)
20、 in the plane of thespecimen. When used with an objective having a numericalaperture lower than the minimum numerical aperture of thehollow cone, only light deviated by the specimen enters theobjective. Objects are seen as bright images against a darkbackground.condenser, darkfield, bispherica darkf
21、ield condenser con-sisting of a convex spherical reflector mounted concentricwith a larger concave reflector. The rays are formed into adiverging cone by the convex reflector. The annular concavereflector then forms a hollow converging cone which isfocused on the subject. See condenser, darkfield.co
22、ndenser, darkfield, paraboloida darkfield condenserconsisting of a reflecting surface in the form of a segment ofa paraboloid of revolution. Parallel rays entering the con-denser around the periphery of the central stop are reflectedfrom the curved surfaces and converge at the focus of theparaboloid
23、. See condenser, darkfield.condenser, variable-focusessentially an Abbe condenser inwhich the upper lens element is fixed and the lower movable.The lower lens may be used to focus the illuminationbetween the elements so that it emerges from the stationarylens as a large diameter parallel bundle. The
24、 field oflow-power objectives may thus be filled without removingthe top element.At the opposite extreme it can be adjusted tohave a numerical aperture as high as 1.3.critical illuminationsee illumination, critical.crystal, birefringenta pertaining to the use of a microscope.curvature of fielda prop
25、erty of lens that causes the image ofa plane to be focused into a curved surface instead of a plane.darkfield condensersee condenser, darkfield.density. opticallogarithm to the vase 10 of the reciprocal oftransmittance.depth of fieldthe depth or thickness of the object space thatis simultaneously in
26、 acceptable focus.depth of focusthe depth or thickness of the image space thatsimultaneously in acceptable focus.diaphragma fixed or adjustable aperture in an opticalsystem. Diaphragms are used to intercept scattered light, tolimit field angles, or to limit image-forming bundles or rays.disk, Airyse
27、e Airy disk.distance, interpupillarysee interpupillary distance.dry objectiveany microscope objective designed for usewithout immersion liquids.electromagnetic lensan electromagnet designed to producea suitably shaped magnetic field for the focusing anddeflection of electrons or other charged partic
28、les in electron-optical instrumentation.electron microscopesee microscope, electron.electron opticsthe science that deals with propagation ofelectrons, as light optics deals with that of light and itsphenomena.eye lenssee lens, eye.eyepiecethe lens system used in an optical for magnificationof the i
29、mage formed by the objective.eyepiece, parfocaleyepieces with common focal planes sothat they are interchangeable without refocusing.eyepiece, positivean eyepiece in which the real image of theobject is formed below the lower lens elements of theeyepiece.filar micrometer or filar eyepiecean eyepiece
30、 equippedwith a fiducial line in its focal plane, that is movable bymeans of a calibrated micrometer screw, in order to makeaccurate measurements of length.focus, principalthe point at which a lens focuses an axialobject pint. Synonymous with focal point.illumination, criticalthe formation of an ima
31、ge of the lightsource in the object field. (Also known as Nelson illumina-tion)illumination, Khlera method of microscopical illumina-tion, first described by A. Khler, in which an image of thesource is focused in the lower focal plane of the condenser,and the field diaphragm is focused in the specim
32、en plane.illumination, obliqueillumination from light inclined at anoblique angle to the optical axis.imagea representation of an object produced by means ofradiation usually with a lens or mirror system.immersion objectivean objective in which a medium ofhigh refractive index is used in the object
33、space to increasethe numerical aperture and hence the resolving power of thelens.interpupillary distancethe distance between the centers ofthe pupils of the eye. The binocular microscope tubes mustbe adjustable for this distance.Khler illuminationsee illumination, Khler.lensa transparent optical ele
34、ment, so constructed that itserves to change the degree of convergence or divergence ofthe transmitted rays.lens, Bertranda small convergent lens placed betweenobjectives and eyepiece. The lens focuses an image of theupper focal plane of the objective on the focal plane of theeyepiece. It is chiefly
35、 used with polarized light for inspectingthe interference figure. It is also convenient for quicklyE 175 82 (2005)e12verifying centering, size, and uniform illumination of anaperture.lens, compounda lens compound of two or more separatepieces of glass or other optical material. These componentpieces
36、 or elements may or may not be cemented together. Acommon form of compound lens is a two-element objective,one element being a converging lens of crown glass and theother a diverging lens of flint glass. The combination ofsuitable glasses or other optical materials (plastics, minerals)properly groun
37、d and polished reduces aberrations normallypresent in a single lens.lens,eyethe lens in an eyepiece nearest to the eye.lens, negativea lens that is thicker on the edges than in thecenter, and which causes parallel light rays to diverge. Alsocalled diverging lens.magnificationa ratio of the size of a
38、n image to its corre-sponding object. This is usually determined by linear mea-surement.magnification, emptymagnification beyohnd which no newinformation is revealed.mechanical stagea device provided for adjusting the posi-tion of a specimen, usually by translation in two directions atright angles t
39、o each othermicrographa graphic reproduction of an object as formedby the microscope or equivalent optical instrument.micromanipulatora mechanical device for making smallmovements inorder to manipulate microscopic probes.microradiography, contacta mehtod of making micro-graphs be means of X rays. Th
40、e specimen is placed close toa fine-grained photographic emulsion at some distance fromthe X-ray source. The X rays pass through the specimen andthe differential adsorption and the scattering of the radiationis recorded by the emulsion. The resulting negative isexamined and photographed through a li
41、ght microscope.microscopean instrument capable of producing a magnifiedimage of a small object.microscope, electronan electron-optical device which pro-duces a magnified image of an object. Detail may berevealed by virtue of selective transmission, reflection, oremission of electrons by the object.m
42、icroscope, field emissionan image-forming device inwhich a strong electrostatic field causes cold emission ofelectrons from a sharply rounded point or from a specimenthat has been placed on that point. The electrons areaccelerated to a phosphorescent screen, or photographicfilm, giving a visible pic
43、ture of the variation of emissionover the specimen surface.microscope, Greenougha stereoscopic mincorscope withpaired objectives, prisms, and eyepieces invented by J.Greenough. The name is sometimes incorrectly used for anystereoscopic microscope with paired objectives showingerect images.microscope
44、, X-raya device for producing enlarged imagesof a specimen by means of X rays. Dioptric systems,analogous to light microscopes, are not available, but contactmicroradiography, point-projection, and reflection tech-niques (which see) provide practical alternatives.microscopicvery small, pertaining to
45、 a very small object orto its fine structure. A microscopic particle requires micro-scopical examination to be adequately visible.microscopicalpertaining to a microscope; pertaining to theuse of a microscope.microscopythe science of the interpretive use, and applica-tions of microscopes.micrurgythe
46、use of a micromanipulator in combination witha microscope.mirror, first or front surfacean optical mirror on which thereflecting surface is applied to the front surface of the mirrorinstead of to the back, that is, to the first surface of incidence.moire pattera pattern developed from interference o
47、r lightblocking, when gratings, screens, or regularly spaced pat-terns are superimposed on one another.Nicol prisma prism, used for polarizing or analyzing light,made by cementing together, with Canada balsam, twopieces of calcite in such a way that the extraordinary rayfrom the first piece passes t
48、hrough the second piece while theordinary ray is reflected to the side into an absorbing layer ofblack paint. When two Nicol prisms are crossed, therefore,no light passes through.normalan imaginary line forming a right angle with thetangent to a curved surface at a particular point. It is used asa b
49、asis for determining angles of incidence, reflection, andrefraction.numerical aperturethe product of the lowest index ofrefraction in the object space multiplied by the sine of halfthe angular aperture of the objective.objectivethe primary magnifying system of a microscope.Asystem, generally of lenses, less frequently of mirrors,forming a real, inverted, and magnified image of the object.objective, fluoritean objective using the mineral fluorite inits construction. It is usually
