JP 1964-025754 — Saburo Murakami
| 7 ELEMENTS / 5 GROUPS |
| EFL 50.006 mm |
| f/2 |
| 2ω = 46° (PATENT) |
| ALL-SPHERICAL |
Inferred unit focus to 0.6 m, modeled by increasing the final BF gap from 37.562469 to 42.591706 mm; the production lens used a linear helicoid, while the patent publishes only the infinity prescription.
| Element | Type | Glass |
|---|---|---|
| L1 | Negative Meniscus | 613586 — SK4 class (catalog equivalent; vendor unconfirmed) |
| L2 | Positive Meniscus | 614551 — SK9 / S-BSM9 / H-ZK8 class (catalog equivalent; vendor unconfirmed) |
| L3 | Positive Meniscus | 614551 — SK9 / S-BSM9 / H-ZK8 class (catalog equivalent; vendor unconfirmed) |
| L4 | Negative Meniscus | 648338 — SF2 class (catalog equivalent; vendor unconfirmed) |
| L5 | Negative Meniscus | 741278 — SF13 / S-TIH13 class (catalog equivalent; vendor unconfirmed) |
| L6 | Positive Meniscus | 744449 — LAF2 / S-LAM2 class (catalog equivalent; vendor unconfirmed) |
| L7 | Biconvex Positive | 744449 — LAF2 / S-LAM2 class (catalog equivalent; vendor unconfirmed) |