CPC G02B 13/0045 (2013.01) [G02B 9/64 (2013.01)] | 9 Claims |
1. An imaging lens comprising in order from an object side to an image side,
a first lens with positive refractive power having an object-side surface being convex in a paraxial region,
a second lens with negative refractive power in a paraxial region,
a third lens with positive refractive power in a paraxial region,
a fourth lens,
a fifth lens with negative refractive power in a paraxial region,
a sixth lens with positive refractive power having an object-side surface being convex in a paraxial region, and
a seventh lens with negative refractive power having an image-side surface being concave in a paraxial region, wherein the following conditional expressions (1), (2), (5′), and (17′) are satisfied:
40.00<vd5<72.00 (1)
3.30<|r10|/f (2)
−8.50<f5/f<=−4.62 (5′)
1.61<=r5/f<=3.11 (17′)
where
vd5: an abbe number at d-ray of the fifth lens,
r10: a paraxial curvature radius of an image-side surface of the fifth lens,
f5: a focal length of the fifth lens,
r5: a paraxial curvature radius of an object-side surface of the third lens, and
f: a focal length of the overall optical system of the imaging lens.
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