RICOH GR LENS 6.0mm f/1.9 (Ricoh GR DIGITAL III)

JP 2010-72639 A — Yoshifumi Sudoh

8 ELEMENTS / 6 GROUPS
6.0 mm
f/1.9 marketed / f/1.93 modeled
2ω = 78.2°
2 ASPHERICAL SURFACES

Focus Mechanism

PUBLISHED patent states only: infinity to 300 mm object-to-image-plane focus. Group I shifts 0.10 mm imageward while Group II shifts 0.14 mm objectward; the stop remains fixed. The production 1 cm macro endpoint is not reconstructed.

Optical Elements (8 physical)

ElementTypeGlass
L1Negative MeniscusS-FSL5 (OHARA)
L2Negative Meniscus (Rear Asphere)L-BSL7 (OHARA)
L3Biconvex PositiveS-LAH59 (OHARA)
L4Biconvex PositiveS-FPL51 (OHARA)
L5Negative MeniscusS-TIH4 (OHARA)
L6Negative MeniscusS-TIM1 (OHARA)
L7Biconvex PositiveS-FPL51 (OHARA)
L8Positive Meniscus (Front Asphere)L-BSL7 (OHARA)