CANON EF 400mm f/4 DO IS USM

US 2002/0015231 A1 — Hideki Ogawa

US 2002/0015231 A1 — Example 1
15 modeled elements / 11 active groups
Design f = 392.025 mm, F/4.12
2ω = 6.32°
r2 radial-polynomial DO phase

Focus Mechanism

Production lens: inner focusing with USM, 3.5 m MFD. Patent Example 1 publishes only the infinity prescription; no internal focus movement is reconstructed (NO_INTERNAL_RECONSTRUCTION).

Optical Elements (15 physical)

ElementTypeGlass
L1Positive MeniscusS-BAL41-equivalent class (564607; vendor unproven)
L2Biconvex PositiveS-BSL7-equivalent class (516641; vendor unproven)
L3Positive MeniscusS-NSL3-equivalent class (518590; vendor unproven)
L4Biconcave NegativeS-LAM7-equivalent class (750353; vendor unproven)
L5Positive MeniscusS-FSL5-equivalent class (487702; vendor unproven)
L6Negative MeniscusS-TIM25-equivalent class (673321; vendor unproven)
L7Negative MeniscusFluorite (CaF2) class
L8Negative Meniscus805254 class (vendor unresolved)
L9Biconvex PositiveS-FSL5-equivalent class (487702; vendor unproven)
L10Biconvex Positive762265 class (vendor unresolved)
L11Biconcave Negative804465/804466 class (vendor unresolved)
L12Biconcave Negative804465/804466 class (vendor unresolved)
L13Biconvex PositiveS-TIM27 / 640345 class (vendor unproven)
L14Negative Meniscus804465/804466 class (vendor unresolved)
L15Biconvex PositiveS-BSL7-equivalent class (516641; vendor unproven)