JP 2021-189377 A, Example 1 — Takakazu Hirose, Keiko Yamada, Yasushi Yamamoto, Hiroshi Yamamoto
| 11 ELEMENTS / 10 GROUPS |
| f = 24.7–48.5 mm |
| F/4.08–6.34 |
| 2ω = 82.5°–48.2° |
| 6 ASPHERICAL SURFACES |
Internal focus via G3 (2 elements, stepping motor). G3 translates toward image for close focus; close-focus gaps are calculated (patent gives infinity gaps only).
| Element | Type | Glass |
|---|---|---|
| L1a | Negative Meniscus | LAC14 (HOYA) |
| L1b | Biconcave Neg. (2× Asph) | COP resin (ZEONEX-type) |
| L1c | Positive Meniscus | PBH21 (OHARA; historical 923209) |
| L2a | Positive Meniscus | FCD1 (HOYA) / S-FPL51 |
| L2b | Biconvex Positive | FCD1 (HOYA) / S-FPL51 |
| Cem | Cement Layer | UV-cure adhesive |
| L2c | Biconcave Negative | S-BAH27 (OHARA) |
| L2d | Biconvex Positive (2× Asph) | M-BACD12 (HOYA) |
| L2e | Negative Meniscus | E-FD2 (HOYA) |
| L3a | Negative Meniscus | TAFD5G (HOYA) |
| L3b | Neg. Meniscus (2× Asph) | COP resin (ZEONEX-type) |
| L4a | Positive Meniscus | E-FD2 (HOYA) |