US 9,784,950 B2 — Masakazu Saori, Yoshimitsu Ohara
| 14 ELEMENTS / 10 GROUPS |
| MARKETED 15-45mm f/2.8 |
| DESIGN f = 15.50-44.04 mm; FNO = 2.9 |
| ALL-SPHERICAL |
CONSTRAINED_RECONSTRUCTION: L13 alone moves approximately 2.787 mm objectward from infinity to the manufacturer 1.0 m MFD. D3 decreases and D5 increases by equal amounts at each zoom position, preserving their adjacent-gap sum. The patent publishes the mechanism and direction but no finite-focus spacing table.
| Element | Type | Glass |
|---|---|---|
| L11 | Negative Meniscus | S-NPH1 (OHARA) |
| L12 | Biconvex Positive | S-FPL51 (OHARA) |
| L13 | Positive Meniscus | S-FSL5 (OHARA) |
| L21 | Biconcave Negative | S-LAL18 (OHARA) |
| L22 | Biconcave Negative | S-LAL18 (OHARA) |
| L23 | Positive Meniscus | S-TIH53 (OHARA) |
| L24 | Negative Meniscus | S-LAH66 (OHARA) |
| L31 | Biconvex Positive | S-LAL14 (OHARA) |
| L32 | Negative Meniscus | S-LAH71 (OHARA) |
| L41 | Positive Meniscus | S-LAL14 (OHARA) |
| L42 | Positive Meniscus | S-FPL51 (OHARA) |
| L43 | Negative Meniscus | S-BAH28 (OHARA) |
| L44 | Biconvex Positive | S-PHM53 (OHARA) |
| L45 | Negative Meniscus | S-TIL26 (OHARA) |