FR 1.066.698 Example 1 — VEB Optik Carl Zeiss Jena / Harry Zöllner (attr.)
| 4 ELEMENTS / 3 GROUPS |
| f ≈ 50.0 mm |
| F/2.8 |
| 2ω ≈ 46.8° |
| ALL SPHERICAL |
Unit focus — entire optical block translates on helicoid; no internal moving elements.
| Element | Type | Glass |
|---|---|---|
| L1 | Plano-Convex Positive | 678555 LaK (≈ Schott N-LaK12) |
| L2 | Biconcave Negative | 612372 F (≈ Schott F3 legacy) |
| L3 | Negative Meniscus | 574425 LF |
| L4 | Biconvex Positive | 661508 SSK (≈ Schott N-SSK5) |
Detailed analysis available in the interactive viewer above.