CPC G02B 13/0045 (2013.01) [G02B 9/62 (2013.01); G02B 13/02 (2013.01)] | 18 Claims |
1. An optical imaging system, sequentially from an object side to an image side of the optical imaging system along an optical axis, comprising:
a first lens having positive refractive power;
a second lens having refractive power;
a third lens having negative refractive power;
a fourth lens having refractive power with a convex object-side surface and a concave image-side surface;
a fifth lens having refractive power; and
a sixth lens having negative refractive power,
wherein Semi-FOV<15°, and
1.9 mm<TTL*ImgH/f<2.7 mm,
where Semi-FOV is half of a maximal field-of-view of the optical imaging system, TTL is a distance along the optical axis from an object-side surface of the first lens to an imaging plane of the optical imaging system, ImgH is half of a diagonal length of an effective pixel area on the imaging plane and f is an effective focal length of the optical imaging system, and
wherein 1.0<(f234−f56)/f<1.8,
where f234 is a combined focal length of the second lens, the third lens, and the fourth lens; f56 is a combined focal length of the fifth lens and the sixth lens; and f is the effective focal length of the optical imaging system.
|