| 摘要 |
A wide-angle imaging lens comprises, in order from an object: a first lens having a negative refractive power; a second lens having a positive refractive power with a convex face directed to the object; an aperture diaphragm; a third lens having a positive refractive power with a convex face directed to an image; and a fourth lens having a positive refractive power with a convex face directed to the object, wherein the following conditional expressions are satisfied. <?in-line-formulae description="In-line Formulae" end="lead"?>N2>=1.7 (1)<?in-line-formulae description="In-line Formulae" end="tail"?> <?in-line-formulae description="In-line Formulae" end="lead"?>N3>=1.7 (2)<?in-line-formulae description="In-line Formulae" end="tail"?> <?in-line-formulae description="In-line Formulae" end="lead"?>N4>=1.7 (3)<?in-line-formulae description="In-line Formulae" end="tail"?> when N2: a refractive index of the second lens at the d-line N3: a refractive index of the third lens at the d-line N4: a refractive index of the fourth lens at the d-line.
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