MINOLTA MD FISHEYE ROKKOR-X 7.5mm f/4 — Optical Cross-Section & Ray Tracing

Home / Lenses / Minolta / MINOLTA MD FISHEYE ROKKOR-X 7.5mm f/4MINOLTA MD FISHEYE ROKKOR-X 7.5mm f/4US 4,009,943↗, Example 2 — Mitsuaki Horimoto
12 ELEMENTS / 8 GROUPS
DESIGN f = 7.50 mm
DESIGN F/4.00
ALL SPHERICAL
EQUIDISTANT PROJECTION / 180 DEG CIRCULAR
Focus MechanismFixed focus. The production lens has no focusing ring and is set near 4 ft (1.2192 m). The patent prints only the infinity state, which is shown here; the approximately 0.05 mm back-focus difference to the production setting is not modeled.
Optical Elements (12 physical)ElementTypeGlass
L1Negative MeniscusBACD16 (Hoya equivalent)
L2Negative MeniscusLAC8 (Hoya equivalent)
L3aPositive MeniscusUnmatched (source nd=1.5934, vd=34.8)
L3bBiconcave NegativeLAC8 (Hoya equivalent)
L4Biconvex PositiveUnmatched (source nd=1.5934, vd=34.8)
L5Plane-Parallel PlateUnmatched (source nd=1.5186, vd=60.1)
L6aBiconcave NegativeUnmatched (source nd=1.805, vd=41.0)
L6bBiconvex PositivePBL6Y (Ohara equivalent)
L7aPositive MeniscusFSL3 (Ohara equivalent)
L7bNegative MeniscusFD110 (Hoya equivalent)
L8aNegative MeniscusLAF3 (Hoya equivalent)
L8bBiconvex PositiveUnmatched (source nd=1.4707, vd=67.4)

Element	Type	Glass
L1	Negative Meniscus	BACD16 (Hoya equivalent)
L2	Negative Meniscus	LAC8 (Hoya equivalent)
L3a	Positive Meniscus	Unmatched (source nd=1.5934, vd=34.8)
L3b	Biconcave Negative	LAC8 (Hoya equivalent)
L4	Biconvex Positive	Unmatched (source nd=1.5934, vd=34.8)
L5	Plane-Parallel Plate	Unmatched (source nd=1.5186, vd=60.1)
L6a	Biconcave Negative	Unmatched (source nd=1.805, vd=41.0)
L6b	Biconvex Positive	PBL6Y (Ohara equivalent)
L7a	Positive Meniscus	FSL3 (Ohara equivalent)
L7b	Negative Meniscus	FD110 (Hoya equivalent)
L8a	Negative Meniscus	LAF3 (Hoya equivalent)
L8b	Biconvex Positive	Unmatched (source nd=1.4707, vd=67.4)