US 2026/0036794 A1 — Emiri Suzuki, Naoto Nishimura
| 16 ELEMENTS / 13 GROUPS |
| DESIGN f = 36.05–96.99 mm |
| PATENT F/4.12 AT ALL STATIONS |
| MODEL F/2.84–4.12 WITH FIXED IRIS |
| 5 ASPHERICAL SURFACES / 3 ELEMENTS |
The patent tabulates infinity focus only, at three zoom stations (36.05, 59.13 and 96.99 mm), so focus is not modeled and the focus control moves nothing. The fifth group (L13–L14) moves toward the image for near objects, but the patent prints no travel or finite-focus spacings. The 0.4 m minimum focus distance is Hasselblad's figure for the wide end (0.5 m at the long end) and is not modeled. Between the printed stations the zoom gaps are linearly interpolated; this is not a published cam, and the paraxial focus sits up to 1.08 mm off the printed image plane between the wide and middle stations.
| Element | Type | Glass |
|---|---|---|
| L1 | Negative Meniscus | E-FD15L (HOYA; equals the patent nd, νd and θgF; supplier unconfirmed) |
| L2 | Positive Meniscus | LAC8 (HOYA; equals the patent nd, νd and θgF; supplier unconfirmed) |
| L3 | Negative Meniscus | TAFD5G (HOYA; equals the patent nd, νd and θgF; supplier unconfirmed) |
| L4 | Negative Biconcave (1x Asph) | M-FCD500 (HOYA; equals the patent nd and νd, catalog θgF 0.5403 against the printed 0.5398; supplier unconfirmed) |
| L5 | Positive Meniscus | NBFD27 (HOYA; equals the patent nd, νd and θgF; supplier unconfirmed) |
| L6 | Negative Meniscus | E-FD80 (HOYA; equals the patent nd, νd and θgF; supplier unconfirmed) |
| L7 | Positive Meniscus | NBFD10 (HOYA; equals the patent nd, νd and θgF; supplier unconfirmed) |
| L8 | Positive Biconvex | FCD1 (HOYA; equals the patent nd, νd and θgF; supplier unconfirmed) |
| L9 | Negative Biconcave | S-NBH51 (OHARA; equals the patent νd and θgF, catalog nd 1.74950 against the printed 1.74951; supplier unconfirmed) |
| L10 | Positive Meniscus | FCD1 (HOYA; equals the patent nd, νd and θgF; supplier unconfirmed) |
| L11 | Positive Biconvex | FCD705 (HOYA; equals the patent nd, νd and θgF; supplier unconfirmed) |
| L12 | Negative Meniscus (2x Asph) | L-LAL13 (OHARA; equals the patent nd, νd and θgF; supplier unconfirmed) |
| L13 | Negative Meniscus (2x Asph) | K-VC181 (SUMITA; equals the patent nd, νd and θgF; supplier unconfirmed) |
| L14 | Negative Meniscus | FC5 (HOYA; equals the patent nd, νd and θgF; supplier unconfirmed) |
| L15 | Negative Meniscus | FCD1 (HOYA; equals the patent nd, νd and θgF; supplier unconfirmed) |
| L16 | Positive Biconvex | FDS24-W (HOYA; equals the patent nd, νd and θgF; supplier unconfirmed) |