US 3,459,469 — Yasuo Takahashi
| 5 ELEMENTS / 4 GROUPS |
| 135mm f/2.5 MARKETED |
| f = 134.498 mm MODELED |
| f/2.4907 MODELED |
| 18° FULL FIELD |
| ALL-SPHERICAL |
CONSTRAINED_RECONSTRUCTION: whole-unit focusing only; all internal optical spacings remain fixed. The patent publishes no focus table. A 1.5 m object-to-image-plane MFD is modeled by increasing the R9-to-image gap from 42.717294 mm at infinity to 57.463464 mm at close focus, equivalent to 14.746170 mm lens-forward travel with a fixed film plane.
| Element | Type | Glass |
|---|---|---|
| L1 | Negative Meniscus | 741278 class (vendor unspecified) |
| L2 | Positive Meniscus | 640602 class (vendor unspecified) |
| L3 | Positive Meniscus | SK1 (SUMITA catalog equivalent for patent coordinate; production supplier unspecified) |
| L4 | Plano-Concave Negative | 720437 class (vendor unspecified) |
| L5 | Positive Meniscus | 720437 class (vendor unspecified) |