US 3,552,833 — Heinz Marquardt
| 6 elements / 5 groups |
| f = 61.4 mm design, 60 mm nominal |
| F/2.8 |
| 40° diagonal field (published) |
| All-spherical modified Gauss |
| Unit focus |
Unit focus. The production lens focuses from infinity to 0.27 m / 1:2 natively, and reaches 1:1 with the Macro-Adapter-R.
| Element | Type | Glass |
|---|---|---|
| L1 | Positive Meniscus | Unmatched (LAF2-class patent e-line value; no verified d-line catalog identity) |
| L2 | Positive Meniscus | Unmatched (693/495 e-line; positive member of front cemented doublet) |
| L3 | Negative Meniscus | Unmatched (dense-flint patent e-line value; no verified d-line catalog identity) |
| L4 | Negative Meniscus | Unmatched (dense flint, 741/262 e-line; no close current HOYA/OHARA match) |
| L5 | Positive Meniscus | BACD16 / S-BSM16 class (e-line catalog match; patent vendor not named) |
| L6 | Positive Meniscus | BACD4 class (e-line catalog match; patent vendor not named) |