US 2,824,495 — Günter Klemt
| 7 ELEMENTS / 6 GROUPS |
| 28.001 mm DESIGN EFL |
| F/4 CALIBRATED MODEL |
| ≈75° PATENT FIELD |
The Retina production lens focuses from infinity to 3 ft (0.9144 m). The patent supplies only one focus state, so focus travel is not modeled.
| Element | Type | Glass |
|---|---|---|
| L1 | Negative Meniscus | N-SK10 — 623569 coordinate; compatible spectral proxy (supplier unconfirmed) |
| L2 | Negative Meniscus | BACD15 — 623581 coordinate; compatible spectral proxy (supplier unconfirmed) |
| L3 | Biconvex Positive | H-BaF8 — 626391 coordinate; compatible spectral proxy (supplier unconfirmed) |
| L4 | Positive Meniscus | H-QK1 — compatible spectral proxy (supplier unconfirmed) |
| L5 | Biconcave Negative | SF15 — 699301 coordinate; compatible spectral proxy (supplier unconfirmed) |
| L6 | Negative Meniscus | SF5 — 673322 coordinate; compatible spectral proxy (supplier unconfirmed) |
| L7 | Biconvex Positive | S-LAL12 — 678553 coordinate; compatible spectral proxy (supplier unconfirmed) |