CPC G02B 13/0065 (2013.01) [G02B 9/12 (2013.01); G02B 13/009 (2013.01); G02B 13/0045 (2013.01); G02B 15/143 (2019.08); G02B 15/1435 (2019.08); G02B 15/143503 (2019.08); G03B 17/17 (2013.01)] | 18 Claims |
1. An optical imaging system comprising:
a first lens, a second lens, a third lens, a fourth lens, fifth lens, a sixth lens, and a seventh lens,
wherein the first to seventh lenses are sequentially disposed from an object side to an imaging plane,
wherein the second lens, the fourth lens, and the sixth lens have positive refractive power, respectively,
wherein a thickness along an optical axis of the fifth lens is greater than a thickness along an optical axis of the first lens,
wherein the optical imaging system satisfies −1.2<fw/f5<−0.6, where fw is a focal length of the optical imaging system at a wide-angle end and f5 is a focal length of the fifth lens,
wherein the optical imaging system satisfies 0.1<Nd2−Nd3<0.2, where Nd2 is a refractive index of the second lens and Nd3 is a refractive index of the third lens, and
wherein the optical imaging system comprises no more than three lens groups and no more than seven lenses.
|