US 2002/0075570 A1 — Hiromitsu Yamakawa
| 9 ELEMENTS / 8 GROUPS |
| f ≈ 150 mm |
| F/3.2 |
| 2ω ≈ 26.2° |
| ALL-SPHERICAL |
Inner focus — G2 (cemented doublet L5+L6) translates along the optical axis; G1, stop, and G3 are fixed.
| Element | Type | Glass |
|---|---|---|
| L1 | Positive Meniscus | S-LAH66 (OHARA) |
| L2 | Positive Meniscus | S-FPL51 (OHARA) |
| L3 | Negative Meniscus | E-FD8 (HOYA, 689312 code) |
| L4 | Positive Meniscus | S-FPL51 (OHARA) |
| L5 | Biconcave Negative | S-LAL52 (OHARA catalog equivalent; production supplier unspecified) |
| L6 | Positive Meniscus | S-LAH60 (OHARA) |
| L7 | Biconvex Positive | LLF4 (SUMITA catalog equivalent for patent coordinate; production supplier unspecified) |
| L8 | Negative Meniscus | S-NBH8 (OHARA) — KZFS-class, ΔPgF ≈ −0.002 |
| L9 | Positive Meniscus | S-LAH66 (OHARA) |