US 5,548,447 Example 1 — Fuji Photo Optical / Nobuaki Toyama
| 7 elements / 6 groups |
| f = 59.998 mm (patent f=100 scaled ×0.6) |
| f/4 |
| 2ω = 59.2° patent; 60° camera specification |
| all-spherical |
| unit-focus model to 0.7 m |
Inferred unit focus. The patent gives no variable-spacing table; close focus is modeled by increasing the final BFD from 44.4518 mm to 50.7215 mm for a 0.7 m film-plane subject distance.
| Element | Type | Glass |
|---|---|---|
| L1 | Positive Meniscus | NBFD10 (HOYA; 834/373; S-LAH60V-class equivalent) |
| L2 | Positive Meniscus | NBFD11 (HOYA; 786/439; S-LAH51-class equivalent) |
| L3 | Negative Meniscus | FD60 (HOYA; 805/255; S-TIH6 equivalent) |
| L4 | Positive Meniscus | BAFD8 (HOYA; 723/380; S-BAH28 equivalent) |
| L5 | Positive Meniscus | NBFD10 (HOYA; 834/373; S-LAH60V-class equivalent) |
| L6 | Negative Meniscus | E-FD2 class (HOYA; 648/338; patent νd = 33.90) |
| L7 | Positive Meniscus | NBFD11 (HOYA; 786/439; S-LAH51-class equivalent) |
Detailed analysis available in the interactive viewer above.