US 2,645,973, Illustrative Embodiment 1 — Hiroshi Ito
| 7 ELEMENTS / 4 GROUPS |
| f ≈ 85.0 mm |
| F/1.5 |
| 2ω = 30° |
| ALL SPHERICAL |
Unit focusing — entire optical assembly moves forward. The 1 m keyframe is a derived extension (patent publishes no close state).
| Element | Type | Glass |
|---|---|---|
| L1 | Positive Meniscus | SK10 (Schott) |
| L2 | Positive Meniscus | K-SK18 (Sumita) |
| L3 | Biconvex Positive | S-BSL7 (OHARA) |
| L4 | Biconcave Negative | S-TIM28 (OHARA) |
| L5 | Biconcave Negative | S-TIL6 catalog equivalent (patent coordinate; production supplier unspecified) |
| L6 | Biconvex Positive | BACED5 catalog equivalent (patent coordinate; production supplier unspecified) |
| L7 | Biconvex Positive | K-SK18 (Sumita) |