US 5,528,428 Ex. 3 — Ohtake & Mori / Nikon
| 7 ELEMENTS / 5 GROUPS |
| f ≈ 28.9 mm |
| F/2.87 |
| 2ω ≈ 74.0° |
| ALL SPHERICAL |
Unit focus — entire lens assembly moves axially.
| Element | Type | Glass |
|---|---|---|
| L1 | Negative Meniscus | S-NSL3 (OHARA) |
| L2a | Biconvex Positive | TAFD25 (HOYA) |
| L2b | Biconcave Negative | E-FD4 (HOYA) |
| L3a | Biconvex Positive | S-LAH59 (OHARA) |
| L3b | Biconcave Negative | EF3 (HOYA) |
| L4 | Positive Meniscus | 797/454 (discontinued lanthanum glass) |
| L5 | Negative Meniscus | 595/355 (close to S-FTM16, OHARA) |
Detailed analysis available in the interactive viewer above.