US 3,591,257 — Walter Mandler, Garry Edwards, Erich Wagner
| 8 ELEMENTS / 6 GROUPS |
| f = 28 mm |
| F/2.8 |
| 2ω ≈ 74° |
| ALL SPHERICAL |
Unit focusing — entire optical assembly translates along the optical axis (0.70 m extension calculated).
| Element | Type | Glass |
|---|---|---|
| L1 | Negative Meniscus | SK16 (Schott catalog equivalent; patent ne 1.62286 / νe 60.08; production supplier unspecified) |
| L2 | Negative Meniscus | SK16 (Schott catalog equivalent; patent ne 1.62286 / νe 60.08; production supplier unspecified) |
| L3 | Biconvex Positive | K-LaSFn16 (SUMITA catalog equivalent of LaF21, catalog ne 1.79226 / νe 47.17; patent ne 1.79227 / νe 47.15; production supplier unspecified) |
| L4 | Negative Meniscus | SF6 (Schott catalog equivalent; patent ne 1.81265 / νe 25.24; production supplier unspecified) |
| L5 | Negative Meniscus | SK16 (Schott catalog equivalent; patent ne 1.62286 / νe 60.08; production supplier unspecified) |
| L6 | Biconvex Positive (near-plano front) | LaF10 class; S-BAH28 catalog e-line spectral proxy (production supplier unspecified) |
| L7 | Negative Meniscus | SF6 (Schott catalog equivalent; patent ne 1.81265 / νe 25.24; production supplier unspecified) |
| L8 | Negative Meniscus | F2 (Schott catalog equivalent; patent ne 1.62408 / νe 36.11; production supplier unspecified) |