US 1,786,916, Example 2 — Willy Merté
| 6 ELEMENTS / 4 GROUPS |
| f = 49.9567 mm |
| F/1.4 |
| ALL-SPHERICAL |
US 1,786,916 Example 2 publishes one static prescription. Focus travel and minimum focus distance are not documented.
| Element | Type | Glass |
|---|---|---|
| L1 | Positive Meniscus | BAF9 — barium-flint dispersion proxy (vintage 642480; supplier unproven) |
| L2 | Biconvex Positive | N-SK10 — dense-crown dispersion proxy (623569; supplier unproven) |
| L3 | Biconcave Negative | QF3 — light-flint dispersion proxy (vintage 576412; supplier unproven) |
| L4 | Biconcave Negative | 673322 — SF5-class dense flint (supplier unproven) |
| L5 | Biconvex Positive | BAF9 — barium-flint dispersion proxy (vintage 642480; supplier unproven) |
| L6 | Biconvex Positive | BAF9 — barium-flint dispersion proxy (vintage 642480; supplier unproven) |