FR 1,471,493 — Ernst Leitz G.m.b.H.
| 7 elements / 5 groups |
| f ≈ 35.1 mm |
| 1:2.8 |
| 2ω ≈ 63.3° |
| all spherical |
Unit focusing. The patent publishes only the infinity prescription; close focus is approximated as rear BF extension to 0.30 m.
| Element | Type | Glass |
|---|---|---|
| L1 | Negative Meniscus | FK5 / N-FK5 class (Schott legacy; patent n_e) |
| L2 | Biconvex Positive | BaSF6-class (Schott legacy barium dense flint, inferred; patent n_e) |
| L3 | Negative Meniscus | Unmatched (flint/barium-flint position; no confident public catalog match; patent n_e) |
| L4 | Biconvex Positive | SK16 / N-SK16 class (Schott legacy dense barium crown; patent n_e) |
| L5 | Biconcave Negative | Unmatched (dense flint; no confident public catalog match; patent n_e) |
| L6 | Negative Meniscus | BaF13-class (Schott legacy barium flint, inferred; patent n_e) |
| L7 | Biconvex Positive | Unmatched (LAK9-class lanthanum crown; patent e-line value stored) |
Detailed analysis available in the interactive viewer above.