Achromatic Lens
An achromatic doublet is the combination of positive and negative elements with different refractive indices. They are computer-optimized to correct for on-and off-axis spherical and chromatic aberrations. When these doublets are used to focus or collimate, the most steeply curved (shortest radius) surface should face the collimated light.

Material:                        BK7 Optical glasses,CaF2,BaF2, MgF2,Ge,Si,Fused Silica

Diameter Tolerance:     +0.0/-0.02mm

Thickness Tolerance:    ± 0.01mm

Surface Accuracy:        λ/4 @632.8nm

Surface Quality:           20-10

Centration:                  1′

Clear Aperture:            > 90%

Bevel:                          0.2mm×45°

Coating:                      user-defined