JP 6814931 B2 — Takahiro Kitada, Shunichiro Yoshinaga, Takakazu Bito
| 11 ELEMENTS / 9 GROUPS |
| DESIGN f = 12.46–57.78 mm |
| DESIGN F/3.62–5.85 |
| 5 ASPHERICAL SURFACES / 3 ELEMENTS |
| PUBLISHED ZOOM AND CLOSE FOCUS, THREE STATIONS |
PUBLISHED: the patent prints infinity and a 250 mm object-to-image close state at all three zoom stations. For close focus L10 (G4) moves toward the image by 0.37, 1.19 and 3.38 mm at the wide, middle and tele stations; the stop travels with G3. Positions between the printed stations interpolate the printed gaps linearly and are not the production cam, so between the wide and middle stations the image can sit up to about 2.1 mm from best focus and the indicated close distance is approximate. The production 0.20 m minimum focus at the wide end is not in the patent and is not modelled.
| Element | Type | Glass |
|---|---|---|
| L1 | Meniscus Negative | NBFD15 (catalog equivalent; production supplier unspecified) |
| L2 | Meniscus Positive | BSC7 (catalog equivalent; production supplier unspecified) |
| L3 | Meniscus Negative | S-LAH95 (catalog equivalent; production supplier unspecified) |
| L4 | Biconcave Negative | S-BSM16 (catalog equivalent; production supplier unspecified) |
| L5 | Meniscus Positive | FDS18 (catalog equivalent; production supplier unspecified) |
| L6 | Biconvex Positive (1 aspheric surface) | K-CSK120 (SUMITA catalog equivalent, a moulding glass; production supplier unspecified) |
| L7 | Biconvex Positive (2 aspheric surfaces) | Unmatched (Panasonic moulding material 1.53380/55.6, resin by the patent's stated preference; no catalog row; line indices from US 2017/0059832 A1) |
| L8 | Meniscus Negative | S-NBH53V (catalog equivalent; production supplier unspecified) |
| L9 | Biconvex Positive | S-FPL51 (catalog equivalent; production supplier unspecified) |
| L10 | Biconcave Negative (2 aspheric surfaces) | Unmatched (Panasonic moulding material 1.53380/55.6, resin by the patent's stated preference; no catalog row; line indices from US 2017/0059832 A1) |
| L11 | Meniscus Positive | E-CF6 (HOYA catalog equivalent, catalog νd 52.15; production supplier unspecified) |