Plano-Concave Lenses are the best choice where object and image are at absolute conjugate ratios greater than 5:1 and less than 1:5 to reduce spherical.Plano-Concave lenses bend parallel input rays so they diverge from one another on the output side of the lens and hence have a negative focal length.The spherical aberration of the Plano-Concave lenses is negative and can be used to balance aberrations created by other lenses. Similar to the Plano-Convex lenses,the curvature surface should face the largest object distance or the infinite conjugate (except when used with high-energy lasers where this should be reversed to eliminate the possibility of a virtual focus) to minimize spherical aberration.
Atoptical provides these lenses with the material of BK7, fused silica ,Si,Ge,CaF2,or other optical glass and crystal ect..
Specifications |
Normal |
High Precision |
Mfg.Limit |
Material : |
N-BK7 |
N-BK7 |
N-BK7 |
Design Index: |
1.5168 |
1.5168 |
1.5168 |
Diameter Tolerance : |
+0/-0.1mm |
+0/-0.05mm |
+0/-0.02mm |
Thickness Tolerance : |
+/-0.1mm |
+/-0.05mm |
+/-0.01mm |
Focal Length Tolerance: |
+/-2% |
+/-1% |
+/-0.5% |
Centeration : |
3 arc min |
1 arc min |
30 arc sec |
Surface Quality : |
60-40 |
40-20 |
10-5 |
Surface Figure : |
3 lambda |
2 lambda |
1 lambda |
Surface Irregularity : |
1 lambda |
1/5 lambda |
1/10 lambda |
Clear Aperture : |
>80% |
>90% |
100% |
Bevel : |
+/-0.2mm*45 deg |
+/-0.1mm*45 deg |
+/-0.05mm*45 deg |
Other materials are also available.
AR coating is available apon request.