JP2025-069516A EXAMPLE 2 — RICOH / NAKAYAMA
| 7 ELEMENTS / 5 GROUPS |
| f ≈ 18.35 mm |
| F/2.89 |
| 2ω ≈ 76.0° |
| 5 ASPHERICAL SURFACES (3 ELEMENTS) |
Front focus — G1+G2 translate forward as a unit for close focus (D23 increases from 3.10 to 5.17 mm). G3 remains fixed. Macro mode: 0.12 m.
| Element | Type | Glass |
|---|---|---|
| L11 | Neg. Meniscus (1× Asph) | L-TIM28 (OHARA) |
| L12 | Biconcave Negative | S-FTM16 (OHARA) |
| L13 | Biconvex Positive | S-LAH58 (OHARA) |
| L21 | Biconvex Positive | S-LAH58 (OHARA) |
| L22 | Biconcave Negative | S-TIM35 (OHARA) |
| L23 | Pos. Meniscus (2× Asph) | S-LAH66 (OHARA) |
| L31 | Neg. Meniscus (2× Asph) | M-TAF101 (HOYA) |
Detailed analysis available in the interactive viewer above.