JP 2018-087903 A — Yoshihito Souma
| 18 ELEMENTS / 12 GROUPS |
| 16-35mm marketed; 16.399-34.194mm computed design EFL |
| f/3.5-4.5 marketed; f/3.55-4.60 modeled |
| 4 ASPHERICAL SURFACES / 2 ELEMENTS |
| 0.35 m PUBLISHED MODEL FOCUS ENDPOINT; 0.25 m MARKETED MFD |
PUBLISHED: Gr2a (cemented L6+L7, surfaces 10-12) translates imageward to the patent's nominal 0.35 m state. The marketed 0.25 m MFD is metadata only; no internal 0.25 m reconstruction is authored.
| Element | Type | Glass |
|---|---|---|
| L1 | Negative Meniscus | TAFD5G (HOYA catalog equivalent; supplier unspecified) |
| L2 | Neg. Meniscus (2× Asph) | L-BAL42 (OHARA catalog equivalent; supplier unspecified) |
| L3 | Biconvex Positive | E-FD2 (HOYA catalog equivalent; supplier unspecified) |
| L4 | Biconcave Negative | TAC8 (HOYA catalog equivalent; supplier unspecified) |
| L5 | Positive Meniscus | E-FD13 (HOYA catalog equivalent; supplier unspecified) |
| L6 | Positive Meniscus | FC5 (HOYA catalog equivalent; supplier unspecified) |
| L7 | Negative Meniscus | N-LAF34 (SCHOTT catalog equivalent of the HOYA TAF1 coordinate; supplier unspecified) |
| L8 | Biconvex Positive | FC5 (HOYA catalog equivalent; supplier unspecified) |
| L9 | Positive Meniscus | FD140 (HOYA catalog equivalent; supplier unspecified) |
| L10 | Negative Meniscus | TAFD35 (HOYA catalog equivalent; supplier unspecified) |
| L11 | Biconvex Positive (2× Asph) | L-BAL42 (OHARA catalog equivalent; supplier unspecified) |
| L12 | Biconvex Positive | FC5 (HOYA catalog equivalent; supplier unspecified) |
| L13 | Negative Meniscus | TAFD35 (HOYA catalog equivalent; supplier unspecified) |
| L14 | Biconcave Negative | TAFD35 (HOYA catalog equivalent; supplier unspecified) |
| L15 | Biconvex Positive | N-BK7 (SCHOTT catalog equivalent of the HOYA BSC7 coordinate; supplier unspecified) |
| L16 | Positive Meniscus | E-FDS1 (HOYA catalog equivalent; supplier unspecified) |
| L17 | Negative Meniscus | TAFD35 (HOYA catalog equivalent; supplier unspecified) |
| L18 | Plano-Concave Negative | TAFD35 (HOYA catalog equivalent; supplier unspecified) |