US 2,516,724 A — Michael Michaelovitch Roossinov
| 6 ELEMENTS / 4 GROUPS |
| f = 69.883 mm |
| f/8 |
| 2ω = 122° |
| ALL-SPHERICAL |
Fixed patent prescription at infinity; no finite-focus movement is modeled.
| Element | Type | Glass |
|---|---|---|
| L1 | Negative Meniscus | Unmatched (Lenzos L-67; code 640433) |
| L2 | Biconvex Positive | BACD4 spectral proxy (Lenzos L-24 / historical SK4 class; production melt unresolved) |
| L3 | Biconcave Negative | LLF1 spectral proxy (Lenzos L-28; production melt unresolved) |
| L4 | Biconcave Negative | LLF1 spectral proxy (Lenzos L-28; production melt unresolved) |
| L5 | Biconvex Positive | BACD4 spectral proxy (Lenzos L-24 / historical SK4 class; production melt unresolved) |
| L6 | Negative Meniscus | Unmatched (Lenzos L-3; reference wavelength unstated; flint coordinate class) |