CANON EF 135mm f/2.8 Soft Focus — Optical Cross-Section & Ray Tracing

Home / Lenses / Canon / CANON EF 135mm f/2.8 Soft FocusCANON EF 135mm f/2.8 Soft FocusUS 4,826,301↗ — Keiji Ikemori
7 ELEMENTS / 6 GROUPS
135.043 mm DESIGN EFL
f/3.341 SHARP / f/2.8 SOFT
18.2° FULL FIELD
1 GLASS-MOLDED ASPHERE
REAR FOCUS / SOFT-FOCUS CONTROL
Focus MechanismCONSTRAINED_RECONSTRUCTION: the patent specifies rear focusing by III-1 but no ordinary-focus spacing table. Only the cemented L5+L6 group translates rearward; D9+D12 remains 25.80 mm. The close endpoint is code-solved for Canon's 1.3 m MFD measured from the focal plane, giving 9.007510523 mm travel with the image plane fixed.
Optical Elements (7 physical)ElementTypeGlass
L1Biconvex Positive623582 class (catalog vendor unresolved)
L2Biconvex PositiveSK16-class coefficient proxy (patent 623607; production supplier unspecified)
L3Biconcave Negative805254 class (catalog vendor unresolved)
L4Negative Meniscus (1× Asph)583594 class (catalog vendor unresolved)
L5Positive Meniscus755275 class (catalog vendor unresolved)
L6Biconcave Negative541472 class (catalog vendor unresolved)
L7Biconvex Positive487702 class (catalog vendor unresolved)

Element	Type	Glass
L1	Biconvex Positive	623582 class (catalog vendor unresolved)
L2	Biconvex Positive	SK16-class coefficient proxy (patent 623607; production supplier unspecified)
L3	Biconcave Negative	805254 class (catalog vendor unresolved)
L4	Negative Meniscus (1× Asph)	583594 class (catalog vendor unresolved)
L5	Positive Meniscus	755275 class (catalog vendor unresolved)
L6	Biconcave Negative	541472 class (catalog vendor unresolved)
L7	Biconvex Positive	487702 class (catalog vendor unresolved)