RICOH GR LENS 18.3mm f/2.8 (Ricoh GR IV) — Optical Cross-Section & Ray Tracing

Home / Lenses / Ricoh / RICOH GR LENS 18.3mm f/2.8 (Ricoh GR IV)RICOH GR LENS 18.3mm f/2.8 (Ricoh GR IV)JP 2025-069516 A↗ — Takahiro Nakayama
7 ELEMENTS / 5 GROUPS
f ≈ 18.35 mm
F/2.89
2ω ≈ 76.0°
5 ASPHERICAL SURFACES (3 ELEMENTS)
Focus MechanismG1+G2 move toward the object; G3 stays fixed. The 0.12 m object-to-image endpoint is an inferred paraxial scenario.
Optical Elements (7 physical)ElementTypeGlass
L11Neg. Meniscus (1× Asph)L-TIM28 (OHARA)
L12Biconcave NegativeS-FTM16 (OHARA)
L13Biconvex PositiveS-LAH58 (OHARA)
L21Biconvex PositiveS-LAH58 (OHARA)
L22Biconcave NegativeS-TIM35 (OHARA)
L23Pos. Meniscus (2× Asph)MC-TAF101-100 (inferred catalog counterpart)
L31Neg. Meniscus (2× Asph)M-TAF31 (inferred catalog counterpart)

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)	MC-TAF101-100 (inferred catalog counterpart)
L31	Neg. Meniscus (2× Asph)	M-TAF31 (inferred catalog counterpart)