Designation:F1181−09(Reapproved2014)StandardTestMethodforMeasuringBinocularDisparityinTransparentParts1ThisstandardisissuedunderthefixeddesignationF1181;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thistestmethodcoverstheamountofbinoculardispar-itythatisinducedbytransparentpartssuchasaircraftwindscreens,canopies,HUDcombiningglasses,visors,orgoggles.Thistestmethodmaybeappliedtopartsofanysize,shape,orthickness,individuallyorincombination,soastodeterminethecontributionofeachtransparentparttotheoverallbinoculardisparitypresentinthetotal“viewingsys-tem”beingusedbyahumanoperator.1.2Thistestmethodrepresentsoneofseveraltechniquesthatareavailableformeasuringbinoculardisparity,butistheonlytechniquethatyieldsaquantitativefigureofmeritthatcanberelatedtooperatorvisualperformance.1.3ThistestmethodemploysapparatuscurrentlybeingusedinthemeasurementofopticalangulardeviationunderMethodF801.1.4Thevaluesstatedininch-poundunitsaretoberegardedasstandard.ThevaluesgiveninparenthesesaremathematicalconversionstoSIunitsthatareprovidedforinformationonlyandarenotconsideredstandard.1.5Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.2.ReferencedDocuments2.1ASTMStandards:2F801TestMethodforMeasuringOpticalAngularDeviationofTransparentParts3.Terminology3.1Definitions:3.1.1angulardeviation—theangulardisplacementofalightrayasitpassesthroughatransparentpart,expressedasanangularmeasurement,forexample,degree,minutesofarc,milliradians.Sinceitisanangularmeasurement,theamountoflineardisplacementincreaseswithdistance.3.1.2binoculardisparity—thedifferencebetweenthetwoimagesontheretinaresultingfro...
