WO 2021/200206 A1, Example 2 — Takuya Kato
| 17 elements / 14 groups |
| f = 12.37-23.28 mm design |
| F/2.91 design, f/2.8 marketed |
| 2ω = 120.4°-85.7° design |
| 8 aspherical surfaces |
Floating inner focus: GP2 and GP4 move independently; d11/d14 and d19/d22 change with focus while the back focal distance remains fixed at each zoom position.
| Element | Type | Glass |
|---|---|---|
| L11 | Negative Meniscus (2x Asph) | M-BACD12 / L-BAL42 class (PGM barium crown, 583/595) |
| L12 | Negative Meniscus (2x Asph) | M-TAF101 class (PGM lanthanum flint, 768/492) |
| L13 | Biconcave Negative | FCD705 class (ED phosphate crown, 550/755) |
| L14 | Biconcave Negative | FCD100 class (Super ED fluorophosphate, 437/951) |
| L15 | Biconvex Positive | S-LAH71 class (dense lanthanum flint, 850/323) |
| L21 | Negative Meniscus | FDS24 class (ultra-dense short flint, 921/240) |
| L22 | Biconvex Positive | E-FD5 / S-TIM25 class (dense flint, 673/322) |
| L31 | Negative Meniscus | TAFD45 / S-LAH98 class (ultra-dense lanthanum flint, 954/323) |
| L32 | Positive Meniscus (2x Asph) | M-PCD51 class (PGM low-dispersion phosphate crown, 592/670) |
| L41 | Negative Meniscus | TAFD45 / S-LAH98 class (ultra-dense lanthanum flint, 954/323) |
| L42 | Biconvex Positive | FCD705 class (ED phosphate crown, 550/755) |
| L51 | Positive Meniscus | S-NPH4 class (ultra-dense short flint, 893/204) |
| L52 | Negative Meniscus | TAFD45 / S-LAH98 class (ultra-dense lanthanum flint, 954/323) |
| L53 | Biconvex Positive | FCD100 class (Super ED fluorophosphate, 437/951) |
| L54 | Negative Meniscus | TAFD55 / S-LAH99 class (ultra-high-index lanthanum flint, 001/291) |
| L55 | Negative Meniscus (2x Asph) | M-TAFD305 class (PGM lanthanum flint, 851/401) |
| L56 | Biconvex Positive | FCD1 / S-FPL51 / N-PK52A class (ED fluorophosphate, 497/816) |