DE 2444954 A1 Example 3
| 8 elements / 4 groups |
| f′ = 75 mm |
| 1:4.5 |
| 105° / 195 mm image circle |
| All-spherical |
Unit focus by bellows or helical extension; no internal focusing groups in the patent.
| Element | Type | Glass |
|---|---|---|
| L1 | Negative Meniscus | FK3 (Schott inquiry glass) |
| L2 | Negative Meniscus | SF5 (Schott legacy dense flint) |
| L3 | Biconvex Positive | SSK2 / N-SSK2 class (Schott) |
| L4 | Biconcave Negative | Unmatched (short-flint / barium-crown boundary; patent ne=1.5629, ve=46.88) |
| L5 | Negative Meniscus | SK12 (Schott legacy dense crown) |
| L6 | Biconvex Positive | SK3 (Schott legacy dense crown) |
| L7 | Negative Meniscus | BaF11 (Schott legacy barium flint) |
| L8 | Negative Meniscus | FK5 / N-FK5 class (Schott) |
Detailed analysis available in the interactive viewer above.