US 2,836,102 — Hiroshi Ito
| 7 ELEMENTS / 5 GROUPS |
| 50 mm (DESIGN 50.513 mm) |
| F/1.2 |
| 2ω = 40° |
| ALL-SPHERICAL |
Unit focusing: the complete objective translates; the model varies only the rear BFD.
| Element | Type | Glass |
|---|---|---|
| L1 | Positive Meniscus | Unmatched (694535 lanthanum crown; H-LaK6A/LAC13/S-LAL13 candidates are non-unique) |
| L2 | Positive Meniscus | S-LAM3 (OHARA; 717479 coordinate equivalent, original Canon melt not identified) |
| L3 | Biconvex Positive | K-SK18 (Sumita; 639555 exact coordinate equivalent, original Canon melt not identified) |
| L4 | Biconcave Negative | S-TIH1 (OHARA; 717295 coordinate equivalent, original Canon melt not identified) |
| L5 | Biconcave Negative | S-NSL36 (OHARA; 517524 close coordinate equivalent to patent 517525, original Canon melt not identified) |
| L6 | Biconvex Positive | Unmatched (694535 lanthanum crown; H-LaK6A/LAC13/S-LAL13 candidates are non-unique) |
| L7 | Biconvex Positive | Unmatched (694535 lanthanum crown; H-LaK6A/LAC13/S-LAL13 candidates are non-unique) |