US 8,508,864 B2 — Iain A. Neil
| 15 ELEMENTS / 11 AIR-SPACED GROUPS |
| 2 PATENT MACRO-GROUPS (G1 + G2) |
| f = 39.026 mm (MODELED) |
| f/1.4 MODELED; T1.4 MARKETED |
| 2 ASPHERICAL SURFACES |
PUBLISHED three-state internal focus: fixed G1; G2 (STO plus source L12-L16) translates 6.190 mm toward object space from F1 to F3. The patent/model close object-to-image distance is 0.39925 m; the marketed 0.45 m close-focus specification is not substituted.
| Element | Type | Glass |
|---|---|---|
| L2 | Biconvex Positive | S-FPL51 (OHARA) |
| L3 | Negative Meniscus (1× Asph) | S-FSL5 (OHARA) |
| L4 | Biconcave Negative | S-FPL53 (OHARA) |
| L5 | Positive Meniscus | S-LAH63 (OHARA) |
| L6 | Negative Meniscus | S-LAM66 (OHARA) |
| L7 | Positive Meniscus | S-FPL51 (OHARA) |
| L8 | Biconvex Positive | S-LAM55 (OHARA) |
| L9 | Biconvex Positive | S-LAM66 (OHARA) |
| L10 | Biconcave Negative | S-NBH51 (OHARA) |
| L11 | Biconvex Positive | S-FPL53 (OHARA) |
| L12 | Positive Meniscus | S-FPL53 (OHARA) |
| L13 | Positive Meniscus | S-FPL53 (OHARA) |
| L14 | Negative Meniscus (1× Asph) | S-TIH6 (OHARA) |
| L15 | Biconvex Positive | S-NPH1 (OHARA) |
| L16 | Positive Meniscus | S-FPL51 (OHARA) |