DE 1,268,404 EXAMPLE 2 — KONSCHACK & LANGE / CARL ZEISS
| 4 ELEMENTS / 4 GROUPS |
| f ≈ 180.1 mm |
| F/2.8 |
| 2ω ≈ 13.7° |
| ALL SPHERICAL |
Unit focus — entire four-element assembly translates forward via quick-focusing helicoid.
| Element | Type | Glass |
|---|---|---|
| L1 | Positive Meniscus | SK16 (Schott) |
| L2 | Positive Meniscus | SK16 (Schott) |
| L3 | Plano-Concave Negative | SF56A / SF11 (Schott, 785261) |
| L4 | Biconvex Positive | SF4 (Schott) |
Detailed analysis available in the interactive viewer above.