JP 2018-106021 A Example 1 — Canon / Ito Daisuke
| 9 elements / 8 groups |
| 15-45mm f/2.8-5.6 |
| Patent f = 15.45-43.70mm |
| 2.83× zoom |
| 7 aspherical surfaces |
Patent-described inner focus by negative Fa moving imageward; close-focus spacings are not published, so the data file preserves the infinity-focus zoom states.
| Element | Type | Glass |
|---|---|---|
| N1 | Negative Meniscus | S-LAH98 (OHARA) |
| N2 | Neg. Meniscus (2× Asph) | 583594 barium-crown class (S-BAL42 / M-BACD12 class; not exact) |
| N3 | Positive Meniscus | S-NPH3 (OHARA) |
| P1 | Biconvex Positive (2× Asph) | MC-LAC130 / M-LAC130 class (HOYA) |
| P2 | Biconvex Positive | S-LAH99 (OHARA) |
| P3 | Biconcave Negative | S-NBH56 (OHARA) |
| L3p | Biconvex Positive (1× Asph) | M-TAF101 (HOYA) |
| Fa | Negative Meniscus | NBFD15 (HOYA) |
| GRP | Pos. Meniscus (2× Asph) | Optical resin / polymer (patent GRP) |
Detailed analysis available in the interactive viewer above.