US 4,057,330, Example 2 — Sei Matsui
| 5 elements / 4 groups |
| f/2.8–f/32 · 7 blades |
| MFD 1.3 m · 52 mm filter |
| Unit focus · All spherical |
Unit focus — entire optical assembly moves on helicoid; only BFD changes
| Element | Type | Glass |
|---|---|---|
| L1 | Positive Meniscus | S-BSM16 (OHARA) |
| L2 | Positive Meniscus | S-BSM16 (OHARA) |
| L3 | Biconvex Positive | SF56A (Schott catalog-equivalent, 785261; production supplier unspecified) |
| L4 | Biconcave Negative | FD3 (HOYA catalog-equivalent, 740282; production supplier unspecified) |
| L5 | Positive Meniscus | E-FD10 (HOYA catalog-equivalent, 728283; SF10 type, production supplier unspecified) |