US 3,442,573 — Karl Macher
| 12 LENSES + REFLEX PRISM |
| 8-40mm f/1.8 |
| SUPER-8 FRAME 4.22 × 5.69 mm |
The patent publishes zoom travel only. Internal focus travel is not modeled; the Bauer C2 installation focuses from 3 ft to infinity.
| Element | Type | Glass |
|---|---|---|
| L1 | Biconvex Positive | 623581 — crown class (supplier unproven) |
| L2 | Biconcave Negative | 805255 — dense-flint class (supplier unproven) |
| L3 | Positive Meniscus | 623581 — crown class (supplier unproven) |
| L4 | Negative Meniscus | 678555 — lanthanum-crown class (supplier unproven) |
| L5 | Positive Meniscus | 805255 — dense-flint class (supplier unproven) |
| L6 | Biconcave Negative | 464658 — FK3 / fluor-crown class (exact vintage supplier unproven) |
| L7 | Negative Meniscus | 620603 — crown class (supplier unproven) |
| L8 | Biconvex Positive | S-BSM22 — coordinate-compatible spectral proxy (supplier unproven) |
| P | Plane-Parallel Prism | 517642 — BK7-class crown (supplier unproven) |
| L9 | Positive Meniscus | 678555 — lanthanum-crown class (supplier unproven) |
| L10 | Positive Meniscus | 744449 — lanthanum-flint class (supplier unproven) |
| L11 | Biconcave Negative | 785261 — dense-flint class (supplier unproven) |
| L12 | Biconvex Positive | 713539 — lanthanum-crown class (supplier unproven) |