DE 401630 — Paul Rudolph
| 6 ELEMENTS / 4 GROUPS |
| f ≈ 100.16 mm (modeled d-line) |
| F/2 (stop calibrated) |
| ALL-SPHERICAL |
DE 401630 Example III publishes no finite-focus state, focusing motion or verified minimum focus distance; focus is not modeled.
| Element | Type | Glass |
|---|---|---|
| L1 | Biconvex Positive | Unmatched (SK/BSM/BACD-family dense-crown coordinate; source D/G′ converted to d, supplier unconfirmed) |
| L2 | Negative Meniscus | Unmatched (light-flint-class coordinate; source D/G′ converted to d, supplier unconfirmed) |
| L3 | Negative Meniscus | Unmatched (F1-family coordinate; modern 626357 class match, source D/G′ converted to d, supplier unconfirmed) |
| L4 | Negative Meniscus | Unmatched (F1-family coordinate; modern 626357 class match, source D/G′ converted to d, supplier unconfirmed) |
| L5 | Negative Meniscus | Unmatched (light-flint-class coordinate; source D/G′ converted to d, supplier unconfirmed) |
| L6 | Biconvex Positive | Unmatched (SK/BSM/BACD-family dense-crown coordinate; source D/G′ converted to d, supplier unconfirmed) |