US 2,968,221, Example I — Harry Zöllner
| 5 ELEMENTS / 4 GROUPS |
| f = 80.61 mm (0.8× scaled) |
| F/2.8 (stop calibrated) |
| 2ω = 55° (patent) |
| ALL SPHERICAL |
Not modeled — fixed Example I optical stack; 1.0 m production MFD retained as metadata only.
| Element | Type | Glass |
|---|---|---|
| L1 | Positive Meniscus | 667331 — dense-flint class (supplier unresolved) |
| L2 | Positive Meniscus | 694535 — H-LaK6A coordinate-compatible proxy (supplier unresolved) |
| L3 | Negative Meniscus | 689311 — dense-flint class (supplier unresolved) |
| L4 | Negative Meniscus | 728283 — dense-flint class (supplier unresolved) |
| L5 | Positive Meniscus | 620603 — crown class (supplier unresolved) |