US 2,959,100 — Hans Lautenbacher
| 6 elements / 6 groups |
| f ≈ 28.00 mm |
| f/3.5 |
| 2ω = 75° |
| All-spherical retrofocus |
Unit focus; close state modeled by increasing BF from 35.227689 mm to 38.836352 mm for a 0.30 m object-to-image distance.
| Element | Type | Glass |
|---|---|---|
| L1 | Negative Meniscus | S-BSM10 equivalent (OHARA; legacy SK10-class, patent nd/vd) |
| L2 | Positive Meniscus | F7 (HOYA catalog equivalent; production supplier unspecified; patent 625356) |
| L3 | Biconvex Positive | BACD4 (HOYA catalog equivalent; production supplier unspecified) |
| L4 | Positive Meniscus | F7 (HOYA catalog equivalent; production supplier unspecified; patent 625356) |
| L5 | Biconcave Negative | SF4 (SCHOTT) |
| L6 | Plano-Convex | K-SSK1 catalog equivalent (patent coordinate; production supplier unspecified) |