MeniscusLenscanincreasetheNAofthesystemwhileonlyaddingslightlytothetotalsphericalaberrati***.TheNegativeMeniscusLensisusedtoincreasethefocallengthofanotherlenswhilemaintainingtheangularresolutionoftheopticalassembly.ThisleSpecifictionofourmeniscuslensasfollow:*MaterialBK7orotheropticalmaterials*DimensionTolerance+0.0~-0.1mm*CenterThickness+/-0.1mm*FocalLengthTolerance+/-1%*SurfaceQuality:40/20*SurfaceFigure:lambda/2at633nmonplanoside*ClearAperture>90%*Chamfer0.25mmat45degreetypical*CoatingOptionalnsshapeisbestusedwhenoneconjugateisrelativelyfarfromthelens.)