US 2025/0334777 A1 — Yoshiaki Kurioka, Kunio Dohno
| 5 ELEMENTS / 5 GROUPS |
| DESIGN f = 24.72 mm |
| DESIGN F/7.96 |
| ALL SPHERICAL |
| FIXED APERTURE |
PUBLISHED: the aperture stop A and lenses L1–L5 move together 4.2736 mm toward the object between infinity and the near state, while the parallel plate P and the image plane stay fixed; the gap from L5 to P (the patent's d11) grows from 12.5000 to 16.7736 mm. The patent prints both states (near object 161.726 mm in front of the stop); positions and distance labels between them are interpolated. The patent's near state is 0.20 m from object to image and its focal length is 24.72 mm, against the marketed 0.25 m minimum focus and 26 mm.
| Element | Type | Glass |
|---|---|---|
| L1 | Positive Meniscus | FCD100 (HOYA; coordinate equivalent; supplier unconfirmed) |
| L2 | Negative Meniscus | FDS18 (HOYA; coordinate equivalent; supplier unconfirmed) |
| L3 | Positive Meniscus | TAF5 (HOYA; coordinate equivalent; supplier unconfirmed) |
| L4 | Negative Meniscus | Unmatched (patent nd=1.69513, vd=24.0; no match in six supplier catalogs) |
| L5 | Positive Meniscus | TAFD55 (HOYA; coordinate equivalent; supplier unconfirmed) |