JP 2016-139087 A EXAMPLE 2 — SIGMA / KŌNO, OGASAWARA
| 11 ELEMENTS / 8 GROUPS |
| f ≈ 13.97 mm |
| F/4.13 |
| 2ω ≈ 90.9° |
| 3 ASPHERICAL SURFACES |
Inner focus — G2 (single FLD biconcave L2a) moves forward toward the object. Gap conservation: Δd4 + Δd6 = 0; total track and BFD fixed. Patent close focus at 200 mm (object to image); production dp0 Quattro specifies MFD = 18 cm.
| Element | Type | Glass |
|---|---|---|
| L1a | Neg. Meniscus (2× Asph) | S-BAL42 (OHARA) |
| L1b | Negative Meniscus | S-FPL51 (OHARA) / FCD1 (HOYA) |
| L2a | Biconcave Negative | FCD100 (HOYA) |
| L3a | Negative Meniscus | FCD515 (HOYA) |
| L3b | Biconvex Positive | BSC7 (HOYA) |
| L3c | Positive Meniscus | FCD100 (HOYA) |
| L3d | Negative Meniscus | S-LAH55V (OHARA) |
| L3e | Biconvex Positive (Equi-Convex) | FCD100 (HOYA) |
| L3f | Biconvex Positive | FCD100 (HOYA) |
| L3g | Negative Meniscus | TAFD30 (HOYA) |
| L3h | Neg. Meniscus (1× Asph) | NBFD13 (HOYA) |
Detailed analysis available in the interactive viewer above.