CPC G02B 9/64 (2013.01) [G02B 27/0025 (2013.01); G02B 3/04 (2013.01); G02B 13/18 (2013.01)] | 15 Claims |
1. An optical imaging system comprising:
a first lens having a positive refractive power,
a second lens having a negative refractive power,
a third lens having a negative refractive power, a convex object-side surface in a paraxial region thereof, and a concave image-side surface in a paraxial region thereof,
a fourth lens having a positive refractive power,
a fifth lens having a refractive power,
a sixth lens having a positive refractive power, and
a seventh lens having a negative refractive power,
wherein the first through seventh lenses are sequentially disposed in ascending numerical order along an optical axis of the optical imaging system from an object side of the optical imaging system toward an image side of the optical imaging system, and
a conditional expression f/f2+f/f3<−0.4 is satisfied, where f is a focal length of the optical imaging system, f2 is a focal length of the second lens, and f3 is a focal length of the third lens.
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