US 4,610,514, Embodiment 3 — Akiyoshi Nakamura
| 7 ELEMENTS / 5 GROUPS |
| DESIGN f = 135 mm |
| DESIGN F/2.8 |
| ALL SPHERICAL |
| INTERNAL FOCUS |
PUBLISHED internal focus: the cemented doublet of Unit II (E5–E6) moves 7.33 mm toward the image while Units I and III stay fixed. The patent does not say whether the stop moves; it is modelled fixed with Unit I. The near end is the patent's printed β = 1/10 state (d7 = 19.79, d10 = 19.23 at f = 100, scaled ×1.35), at 1.525 m object to image. The production lens focuses to 1.0 m (0.16×); the patent prints no state that close.
| Element | Type | Glass |
|---|---|---|
| E1 | Biconvex Positive | BACD4 (HOYA catalog equivalent; production supplier unspecified) |
| E2 | Positive Meniscus | BACD4 (HOYA catalog equivalent; production supplier unspecified) |
| E3 | Positive Meniscus | H-LaK67 (CDGM; nearest catalog row to patent nd 1.6710, νd 51.7; production glass unspecified) |
| E4 | Negative Meniscus | S-TIH4 (OHARA catalog equivalent; production supplier unspecified) |
| E5 | Biconvex Positive | S-TIH6 (OHARA catalog equivalent; production supplier unspecified) |
| E6 | Biconcave Negative | S-BSM25 (OHARA catalog equivalent; production supplier unspecified) |
| E7 | Biconvex Positive | N-BK7 (Schott catalog equivalent; production supplier unspecified) |