JP 2706781 B2, sole example — Eiki Matsuo, Hiroyuki Minagawa, Jun Ogawa
| 12 ELEMENTS / 10 GROUPS |
| DESIGN f = 25.78–73.05 mm |
| DESIGN F/4–5.6 |
| ALL SPHERICAL |
| 17 × 24 mm FRAME |
Only infinity focus is modeled. The patent describes near focusing by moving G3 toward the image, but supplies no quantitative near-focus travel. The patent prints the wide and tele states. The interpolated intermediate zoom path keeps G1 and G3 coupled and D5+D12 constant, with D5 varying linearly. The rear image gap is calculated for a fixed image plane while preserving the interpolated endpoint defocus. Both printed endpoint prescriptions are unchanged; intermediate positions are not published lens positions or measured factory cam motion. Aperture variation is interpolated. No finite-focus positions are modeled.
| Element | Type | Glass |
|---|---|---|
| L1 | Negative Meniscus | K-SFLD6 (SUMITA catalog-equivalent class; supplier unconfirmed) |
| L2 | Biconvex Positive | LLF6 (SUMITA catalog-equivalent class; supplier unconfirmed) |
| L3 | Positive Meniscus | S-FSL5 (OHARA catalog equivalent; production supplier unspecified) |
| L4 | Negative Meniscus | LASFN14 (SUMITA catalog-equivalent class; supplier unconfirmed) |
| L5 | Biconcave Negative | F5 (Schott catalog equivalent; production supplier unspecified) |
| L6 | Biconvex Positive | SFLDN3 (SUMITA catalog-equivalent class; supplier unconfirmed) |
| L7 | Negative Meniscus | LASFN14 (SUMITA catalog-equivalent class; supplier unconfirmed) |
| L8 | Biconvex Positive | S-FTM16 (OHARA catalog equivalent; production supplier unspecified) |
| L9 | Biconvex Positive | S-BAL14 (OHARA catalog equivalent; production supplier unspecified) |
| L10 | Biconcave Negative | K-SFLD6 (SUMITA catalog-equivalent class; supplier unconfirmed) |
| L11 | Positive Meniscus | K7 (SUMITA catalog-equivalent class; supplier unconfirmed) |
| L12 | Biconvex Positive | K7 (SUMITA catalog-equivalent class; supplier unconfirmed) |