1、BRITISH STANDARD BS EN ISO 15253:2000 Incorporating Corrigendum No. 1 Ophthalmic optics and instruments Optical devices for low-vision aids The European Standard EN ISO 15253:2000 has the status of a British Standard ICS 01.040.11; 11.040.70; 11.180 BS EN ISO 15253:2000 This British Standard, having
2、 been prepared under the direction of the Health and Environment Sector Committee, was published under the authority of the Standards Committee and comes into effect on 15 November 2000 BSI 02 August 2002 ISBN 0 580 36632 4 National foreword This British Standard is the official English language ver
3、sion of EN ISO 15253:2000. It is identical with ISO 15253:2000. It supersedes BS 7522-1:1992 and BS 7522-2:1993 which are withdrawn. The UK participation in its preparation was entrusted by Technical Committee CH/78, Ophthalmic optics, to Subcommittee CH/78/8, Vision aids, which has the responsibili
4、ty to: A list of organizations represented on this subcommittee can be obtained on request to its secretary. Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Catalogue under the section entitled “Intern
5、ational Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online. This publication does not purport to include all the necessary provisions of a contract. Users are responsible for their correct application. Compliance with a B
6、ritish Standard does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international
7、 and European developments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the EN ISO title page, the EN ISO foreword page, the ISO title page, pages ii to iv, pages 1 to 21, the annex ZA page, an inside back cover and a back cover. The B
8、SI copyright date displayed in this document indicates when the document was last issued. Amendments issued since publication Amd. No. Date Comments 13964 Corrigendum No. 1 02 August 2002 Addition of supersession details to national forewordEUROPEANSTANDARD NORMEEUROPENNE EUROPISCHENORM ENISO15253 S
9、eptember2000 ICS01.004.70 Englishversion OphthalmicopticsandinstrumentsOpticaldevicesfor enhancinglowvision(ISO15253:2000) OptiqueetinstrumentsophtalmiquesDispositifsoptiques pourmalvoyants(ISO15353:2000) AugenoptikundophthalmischeInstrumenteVergrernde SehhilfenfrSehbehinderte(ISO15253:2000) ThisEur
10、opeanStandardwasapprovedbyCENon15September2000. CENmembersareboundtocomplywiththeCEN/CENELECInternalRegulationswhichstipulatetheconditionsforgivingthisEurope an Standardthestatusofanationalstandardwithoutanyalteration.Uptodatelistsandbibliographicalreferencesconcernings uchnational standardsmaybeobt
11、ainedonapplicationtotheCentralSecretariatortoanyCENmember. ThisEuropeanStandardexistsinthreeofficialversions(English,French,German).Aversioninanyotherlanguagemadebytra nslation undertheresponsibilityofaCENmemberintoitsownlanguageandnotifiedtotheCentralSecretariathasthesamestatusast heofficial versio
12、ns. CENmembersarethenationalstandardsbodiesofAustria,Belgium,CzechRepublic,Denmark,Finland,France,Germany,Greece, Iceland,Ireland,Italy,Luxembourg,Netherlands,Norway,Portugal,Spain,Sweden,SwitzerlandandUnitedKingdom. EUROPEANCOMMITTEEFORSTANDARDIZATION COMITEUROPENDENORMALISATION EUROPISCHESKOMITEEF
13、RNORMUNG CentralSecretariat:ruedeStassart,36B1050Brussels 2000CEN Allrightsofexploitationinanyformandbyanymeansreserved worldwideforCENnationalMembers. Ref.No.ENISO15253:2000EForeword Thetext of the InternationalStandar dI SO15253:200 0hasb een preparedby Technical Committee ISO/TC172“Opticsandoptic
14、alinstruments“i n collaboration with Technical CommitteeCEN/ TC170“Ophthalmicoptics“,thesecretariatof whichisheldbyDIN. ThisE uropean Standardshallb e giventh est atus ofan ationalstand ard,eith erbypublication ofa nidenticaltextorbyendors ement, at thel atestby March2001,andconflictingn ational sta
15、ndardsshallbe withdrawnat thel atestby March2001. Accordingt ot heCEN/CENELECI nternalRe gulations, then ationalstand ardsor ganizations of the followingcountrie s areboun d to implementthisEuropeanStandard:Austria,Be lgium, CzechRepublic,Denmark,Finland,France, Germany, Greece,Iceland, Ireland, Ita
16、ly, Luxembourg,N etherlands,Nor way,Portu gal,Spain,S weden,S witzerlandandth eUnited Kingdom. Endorsementnotice Thetext of the InternationalStandar dI SO15253:200 0 wasapprovedbyCENasaE uropean Standard withoutanymod ification. NOTE:N ormativer eferencest oI nternationalStand ardsareliste dinannexZ
17、 A (normative). ENISO15253:2000Referencenumber ISO15253:2000(E) INTERNATIONAL STANDARD ISO 15253 Firstedition 2000-09-15 Ophthalmicopticsandinstruments Opticaldevicesforenhancinglowvision OptiqueetinstrumentsophtalmiquesDispositifsoptiquespour malvoyants ENISO15253:2000ii ENISO15253:2000 iii Content
18、s Page Foreword.iv 1 Scope1 2 Normativereferences1 3 Termsanddefinitions.1 4 Classification6 4.1 Magnifiers.6 4.2 TelescopesDistancevision.6 4.3 TelescopesNear-vision/telemicroscopes6 4.4 TelescopesAdjustable.6 5 Requirements.6 5.1 Opticalcharacteristics6 5.2 Materialsandconstruction.8 6 Environment
19、alconditionsofuse.8 7 Testmethods9 7.1 General9 7.2 EquivalentpowerMagnifiers.9 7.3 AngularmagnificationTelescopes9 7.4 Resolutiontest.9 7.5 Determinationoflateralvariationofmagnification13 8 Markingandinstructionsforuse.13 8.1 Marking.13 8.2 Informationtobeprovidedbythemanufacturer.13 AnnexA(inform
20、ative)Determinationoflateralvariationofmagnification.14 AnnexB(informative)Listofequivalentterms19 ENISO15253:2000iv Foreword ISO(theInternationalOrganizationforStandardization)isaworldwidefederationofnationalstandardsbodies(ISO memberbodies).TheworkofpreparingInternationalStandardsisnormallycarried
21、outthroughISOtechnical committees.Eachmemberbodyinterestedinasubjectforwhichatechnicalcommitteehasbeenestablishedhas therighttoberepresentedonthatcommittee.Internationalorganizations,governmentalandnon-governmental,in liaisonwithISO,alsotakepartinthework.ISOcollaboratescloselywiththeInternationalEle
22、ctrotechnical Commission(IEC)onallmattersofelectrotechnicalstandardization. InternationalStandardsaredraftedinaccordancewiththerulesgivenintheISO/IECDirectives,Part3. DraftInternationalStandardsadoptedbythetechnicalcommitteesarecirculatedtothememberbodiesforvoting. PublicationasanInternationalStanda
23、rdrequiresapprovalbyatleast75%ofthememberbodiescastingavote. AttentionisdrawntothepossibilitythatsomeoftheelementsofthisInternationalStandardmaybethesubjectof patentrights.ISOshallnotbeheldresponsibleforidentifyinganyorallsuchpatentrights. InternationalStandardISO15253waspreparedbyTechnicalCommittee
24、ISO/TC172,Opticsandoptical instruments,SubcommitteeSC7,Ophthalmicopticsandinstruments. AnnexesAandBofthisInternationalStandardareforinformationonly. ENISO15253:2000 1 OphthalmicopticsandinstrumentsOpticaldevicesfor enhancinglowvision 1 Scope ThisInternationalStandardappliestoopticaldevicesspecifiedb
25、ythemanufacturerforusebyvisuallyimpaired personsasopticallow-visionaids.Itspecifiestheopticalandmechanicalrequirementsandtestmethodsforsuch devices,includingopticaldeviceswithelectricalcomponentssuchasilluminators. Itdoesnotapplytoelectro-opticaldevicesforenhancinglowvision. NOTE Requirementsandtest
26、methodsforelectro-opticaldevicesforenhancinglowvisionarespecifiedinISO15254, OphthalmicopticsandinstrumentsElectro-opticaldevicesforlowvision. 2 Normativereferences Thefollowingnormativedocumentscontainprovisionswhich,throughreferenceinthistext,constituteprovisionsof thisInternationalStandard.Fordat
27、edreferences,subsequentamendmentsto,orrevisionsof,anyofthese publicationsdonotapply.However,partiestoagreementsbasedonthisInternationalStandardareencouragedto investigatethepossibilityofapplyingthemostrecenteditionsofthenormativedocumentsindicatedbelow.For undatedreferences,thelatesteditionofthenorm
28、ativedocumentreferredtoapplies.MembersofISOandIEC maintainregistersofcurrentlyvalidInternationalStandards. ISO12870,OphthalmicopticsSpectacleframesGeneralrequirementsandtestmethods. ISO14889,OphthalmicopticsSpectaclelensesFundamentalrequirementsforuncutfinishedlenses. ISO15004:1997,Ophthalmicinstrum
29、entsFundamentalrequirementsandtestmethods. 3 Termsanddefinitions ForthepurposesofthisInternationalStandard,thefollowingtermsanddefinitionsapply.Thesymbolsforcertainof thesetermsarelanguage-dependent.Equivalenttermsinotherlanguages,andthecorrespondingsymbolsusedin thoselanguagesaswellasinEnglish,areg
30、iveninannexB. 3.1 astronomicaltelescope Kepleriantelescope compoundopticalsystem,afocalinnormaladjustment,consistingofapositiveobjectiveelementorgroupanda positiveocularelementorgroupformingamagnified,invertedimage 3.2 binocularaid opticaldevice,usuallyconsistingoftwoseparateopticalsystemsmountedina
31、lignment,intendedtobeusedwith botheyessimultaneously 3.3 biocularaid opticaldeviceinwhichbotheyesviewthroughasingleopticalsystem ENISO15253:20002 3.4 distancecap negativelensplacedinfrontofanear-visiontelescope/telemicroscopeobjectivetoadaptthedeviceforviewinga distantobject 3.5 equivalentpower reci
32、procaloftheequivalentfocallengthinairmeasuredinmetres NOTE Equivalentpowerisexpressedindioptres,orreciprocalmetres. 3.6 eyepiece ocular opticalelementorgroupnearesttotheeyeinanopticalimagingsystem,usedforviewingtheimageformedbythe objective 3.7 focallength lineardistanceseparatingtheprincipalfocalpo
33、int(orfocus)ofanopticalsystemfromapointofreference SeeFigure1. NOTE Thedistanceneedstobefurtherspecifiedinaccordancewiththepointofreferencechosen,e.g.vertex,principal point.Seedefinitions3.7.1to3.7.3. 3.7.1 backvertexfocallength distanceinanopticalsystemfromthebacksurfacetothebackfocalpoint,measured
34、alongtheopticalaxis(axisof symmetry) SeeFigure1. 3.7.2 frontvertexfocallength distanceinanopticalsystemfromthefrontsurfacetothefrontfocalpoint,measuredalongtheopticalaxis(axisof symmetry) SeeFigure1. 3.7.3 equivalentfocallength distanceinanopticalsystemfromafocalpointtothecorrespondingprincipalpoint
35、,measuredalongtheoptical axis(axisofsymmetry) SeeFigure1. NOTE Seeequivalentpower(3.5). 3.8 focusingtelescopicdevice deviceintendedtobeadjustedbytheuserforarangeofobjectdistances 3.9 freeworkingdistance opticallowvisionaid distancebetweenthemostanteriorportionofanear-visiontelescope/telemicroscopean
36、d theobject ENISO15253:2000 3 Key 1 Frontvertexfocallength 2 Backvertexfocallength 3 Focallength 4 Equivalentfocallength Figure1Illustrationoffocallengths 3.10 Galileantelescope compoundopticalsystem,afocalinnormaladjustment,consistingofapositiveobjectiveelementorgroupanda negativeocularelementorgro
37、upformingamagnified,erectimage 3.11 handmagnifier deviceintendedtobepositionedandsupportedbytheusershandandwithoutartificialsupport 3.12 linearfieldofview ofalowvisionaid maximumobservableextentoftheobjectplanevisiblethroughthelowvisionaidunderthe conditionsofusestatedbythemanufacturer 3.13 lowvisio
38、naid deviceusedbyvisuallyimpairedpersonstoenhancevision 3.14 lowvision-aidtelescope opticalsystem,KeplerianwithinvertedimageorGalilean,thatformsamagnifiedretinalimageofanobject 3.14.1 handtelescope telescopedesignedtobehand-held 3.14.2 spectacletelescope telescopemountedinoronaspectacleframe 3.15 ma
39、gnification ratiobetweenanylineardimensionoftheretinalimagewhenthemagnifyingdeviceisinuseandthe correspondingdimensionwhentheobjectisviewedwithoutthemagnifyingdevice ENISO15253:20004 3.15.1 angularmagnification ratiooftheanglesubtendedbytheimagetothatsubtendedbytheobjectataviewingpointofreferencesuc
40、has theentrancepupiloftheeye 3.15.2 nominalmagnification M formagnifiers magnificationcalculatedfromtheproductofthereferenceseeingdistance(see3.20),inmetres, andtheequivalentpowerF(see3.5),indioptres EXAMPLE Withareferenceseeingdistanceof0,25mthenominalmagnificationiscalculatedfromtheformula M=0,25F
41、. 3.15.3 trademagnification(deprecated) M trade formagnifiers magnificationcalculatedfromtheformula: M trade =M+1 NOTE Thisdefinitionisincludedsincesometextbooksonlowvisionrefertotrademagnification.Thistermshouldnotbe usedinfuture. 3.16 magnifier lowvision-aidmicroscope lenssystemdesignedtoproducean
42、enlargedimage NOTE Itmaybeasimplesingleelementoracompoundmultiple-elementsystem. 3.16.1 spectaclemagnifier spectaclemicroscope magnifierintheformofspectaclesandintendedtobewornasspectacles,mountedorheldclosetotheeye,which includespowerinadditiontoanormalnearcorrection 3.16.2 illuminatedmagnifier mag
43、nifierincorporatingillumination 3.17 monocularaid opticaldevicetobeusedbeforeonlyoneeye 3.18 opticaldimensions zoneofopticaldimensions opticalzoneofmagnifier usablelinearsizeofamagnifierwhenmounted NOTE Itisexpressedinmillimetres. 3.19 readingcap positivelensplacedinfrontofatelescopicobjectivetoadap
44、tthedeviceforviewinganearobject ENISO15253:2000 5 3.20 referenceseeingdistance leastdistanceofdistinctvision(deprecated) agreeddistanceof250mmbetweentheanteriorcornealvertexoftheeyeandtheobjectobserved NOTE Thereferenceseeingdistanceisused,aboveall,asareferenceparameterforcalculatingthemagnification
45、of opticalinstrumentsusedfornearvision. 3.21 relativedistancemagnification changeinthesizeoftheretinalimagethatisobtainedbychangingtheviewingdistance 3.22 resolution smallestseparationbetweentwodetails,expressedasalinearorangularmeasurement,atwhichapairofpoints mayberecognizedasbeingseparateunderagi
46、vensetofconditions 3.23 standmagnifier magnifierinwhichthesupportisdesignedtopositiontheopticalsystematasetoradjustabledistancefromthe objecttobeviewed 3.23.1 verteximagedistance forstandmagnifiers distancefromthemagnifiersurfacenearesttotheeyetothevirtualimagewhentheobjectis placedatthedesignatedpo
47、sition SeeFigure2. 3.23.2 exitimagevergence forstandmagnifiers reciprocaloftheverteximagedistance,expressedinmetres NOTE Theunitofvergenceisthedioptre. Key 1 Verteximagedistance 2 Imageplane 3 Objectplane Figure2Illustrationofverteximagedistance,objectplaneandimageplane ENISO15253:20006 3.24 telemic
48、roscope near-visiontelescope telescopeadaptedforviewingnearobjects 3.25 terrestrialtelescope astronomicaltelescopetowhichhasbeenaddedanerectingsystem 4 Classification 4.1 Magnifiers a) Hand-held b) Stand c) Head-mounted,includingspectaclesandspectacle-mounted 4.2 TelescopesDistancevision a) Hand-held b) Head-mounted,includingspectaclesandspectacle-mounted 4.3 TelescopesNear-vision/telemicroscop
