US 2,645,974 — HIROSHI ITO / CANON
| 6 ELEMENTS / 4 GROUPS |
| f ≈ 28.0 mm |
| F/3.5 |
| 2ω = 75° |
| ALL SPHERICAL |
Unit focusing — entire lens moves as rigid unit.
| Element | Type | Glass |
|---|---|---|
| L1 | Positive Meniscus | SK4 (Schott) |
| L2 | Biconvex Positive | SK16 (Schott) |
| L3 | Biconcave Negative | F7 (Schott) |
| L4 | Biconcave Negative | BaF3 (Schott) |
| L5 | Biconvex Positive | SK14 (Schott) |
| L6 | Plano-Convex Positive | SK14 (Schott) |
Detailed analysis available in the interactive viewer above.