Positive Achromatic Lenses

Positive achromatic lenses

Positive achromatic lenses(Spherical doublets&triplets) are often cemented or closely air-spaced, consist of positive and negative glass lenses with different refractive index. These elements have been corrected for chromatic aberration with respect to two selected wavelengths.

Glass material: N-BK7 and etc

Desight wavelength: 480nm,546.1nm,643.8nm

Diameter tollerance: +0.0, -0.2mm

Thickness tollerance:  +0.2, -0.2mm

Focal length tollerance: ±2%

Centration: less than 3arc min

Clear aperture: ≥ 85%

Surface quality:60/40,40/20 (scratch&dig)

Surface flatness: λ/4

Positive achromatic lenses(spherical doublets)
Item numberf (mm)Ф (mm)R1 (mm)R2=R3 (mm)R4 (mm)tc1 (mm)t c2 (mm)f b (mm)Lens ALens B
PAL011066.546-4.055-23.233.60.87.54SK9SF15
PAL02201012.32-0.902-25.233.8117.625N-BK7SF5
PAL033012.718.536-13.49-37.844.01.327.36N-BK7SF5
PAL044012.725.23-17.539-48.753.41.337.778N-BK7SF5
PAL05501831.69-22-60.574.81.546.987N-BK7SF5