Achromatic lens doublet
Material | BK7 or other optical glass, Fused Silica, ZnSe, CaF2 |
---|---|
Diameter Tolerance | +0.00/-0.20mm |
Focal Length Tolerance | ±2% @587.6nm |
Centration | 3 arc minutes |
Clear Aperture | >90% |
Surface quality | Grade IV |
ΔN | 1-5 |
The achromatic lens is far superior to that of a single lens, which is suitable for the demand for imaging and beam control needs.
For different coating, we have chosen three kinds of typical wavelengths to design lenses.
- For 400-700 nm, we choose 486.1nm, 587.6nm, and 656.3nm;
- For 700-1100nm, we choose 706.5nm, 855nm and 1015nm;
- For 1100-1650 nm, we choose 1016nm, 1330nm and 1550nm. The focal length offset can be maintained less than 0.5 mm within the design bandwidth.