US 4,025,167 Embodiment 2 — Olympus / Ikeda
| 15 elements / 11 groups |
| 85-250mm |
| f/5 constant aperture |
| 2ω ≈ 29°-10° |
| All-spherical |
Front-group focusing. Group I advances for close focus; close-focus D1 values are paraxially inferred for 2.0 m because the patent gives 3 m aberration curves but no close-focus spacing table.
| Element | Type | Glass |
|---|---|---|
| L1 | Biconvex Positive | S-FSL5 (OHARA) / FK5 class |
| L2 | Biconvex Positive | S-BSM16 (OHARA) / N-SK16 class |
| L3 | Biconcave Negative | S-TIH11 (OHARA) / SF11 class |
| L4 | Biconcave Negative | 569632 — dense crown (patent glass code) |
| L5 | Plano-Convex Positive | FD140 (HOYA) / PBH14 (OHARA) class |
| L6 | Biconcave Negative | PSK53A / K-PSKn2 class |
| L7 | Negative Meniscus | 569632 — dense crown (patent glass code) |
| L8 | Biconvex Positive | K-SSK9 (Sumita) / BSM28 class |
| L9 | Negative Meniscus | S-TIH18 (OHARA) / FD18 class |
| L10 | Biconvex Positive | 498650 — borosilicate crown (patent glass code) |
| L11 | Biconvex Positive | N-BALF5 / BAL5 class |
| L12 | Biconcave Negative | S-LAH53 (OHARA) |
| L13 | Biconvex Positive | F8 class (Hikari / HOYA) |
| L14 | Biconcave Negative | J-LAF02 class (Hikari; patent 720/437) |
| L15 | Biconvex Positive | N-SK11 (SCHOTT) / BACD11 (HOYA) class |
Detailed analysis available in the interactive viewer above.