RICOH GR LENS 26.1mm f/2.8 (Ricoh GR IIIx)

US 2022/0026670 A1 — Kazuyasu Ohashi

7 ELEMENTS / 5 GROUPS
f = 26.05 mm
F/2.87
2ω = 56.6°
2 MODELED ASPHERES; S12 UNRESOLVED

Focus Mechanism

Reconstructed unit focus: all seven elements and the stop translate 4.85519 mm for an assumed 20 cm image-to-object distance. No finite patent focus schedule; S12 asphere coefficients remain unavailable.

Optical Elements (7 physical)

ElementTypeGlass
L1Pos. Meniscus (1× Asph)OHARA L-LAH85V (patent-listed)
L2Negative MeniscusOHARA S-NBH58
L3Biconcave NegativeOHARA S-TIM27
L4Biconvex PositiveOHARA S-LAH58
L5Biconvex PositiveJ-LASKH2 — compatible counterpart; patent glass-name conflict
L6Biconcave NegativeOHARA S-TIL6
L7Neg. Meniscus (2× Asph)OHARA L-LAH86 (patent-listed; Pg,F=0.5943)