DE 843 305 — Ludwig Bertele
| 4 ELEMENTS / 4 GROUPS |
| ALL-SPHERICAL |
| 135 FORMAT |
The patent supplies only an infinity-focus prescription. The reported 1.5 m close-focus distance is product information; focus travel is not modeled.
| Element | Type | Glass |
|---|---|---|
| L1 | Positive Meniscus | N-PSK3 — coordinate-compatible spectral proxy (supplier unconfirmed) |
| L2 | Positive Meniscus | N-SK16 — 620603 coordinate; compatible spectral proxy (supplier unconfirmed) |
| L3 | Negative Meniscus | S-TIH18 — coordinate-compatible spectral proxy (supplier unconfirmed) |
| L4 | Positive Meniscus | LAFN7 — coordinate-compatible spectral proxy (supplier unconfirmed) |