| 摘要 |
To provide a zoom lens capable of achieving stable optical quality by inhibiting an effect of assemble errors during manufacturing. A zoom lens includes a positive first lens group G1, a negative second lens group G2, a positive third lens group G3, and a positive fourth lens group G4, which are arranged from an object side in that order, and during variation in lens position from a wide angle end state to a telescopic end state, G1 and G3 are fixed, G2 is moved toward an image side, G4 moves so as to compensate fluctuations in image-surface position due to the shift of G2, and an aperture diaphragm S is fixed adjacent to the object side of G3, etc. G2 includes a negative meniscus lens L21 with a concave surface opposing the image side and a cemented lens L22 of a biconcave lens and a positive lens with a convex surface opposing the object side, which are arranged from the object side in that order, and the negative meniscus lens is a compound lens of a glass lens and a resin lens PL formed adjacent to the image side of the glass lens, the lens surface adjacent to the image side of the resin lens is aspheric, and the conditional equation (1) below is satisfied: <?in-line-formulae description="In-line Formulae" end="lead"?>n2>1.75, (1)<?in-line-formulae description="In-line Formulae" end="tail"?> where n2 is the average refractive index of glass constituting G2.
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