Camera lens system
View Patent ↗A camera lens system is disclosed. The camera lens system includes five lens groups lined up from the object side. The lens groups includes a first lens group having a first lens having a positive refractive power; a second lens group having a second lens having a negative refractive power; a third lens group having a third lens having a positive refractive power and the a fourth lens having a negative refractive power; a fourth lens group having a fifth lens having a convex image side surface and a positive refractive power; a fifth lens group having a sixth lens having a concave image side surface and a negative refractive power. An image side surface of the third lens is connected to an object side surface of the fourth lens.
1. A camera lens system comprising five lens groups lined up from the object side, the lens groups including:
a first lens group comprising a first lens having a positive refractive power;
a second lens group comprising a second lens having a negative refractive power;
a third lens group comprising a third lens having a positive refractive power and a fourth lens having a negative refractive power, an image side surface of the third lens being cemented to an object side surface of the fourth lens;
a fourth lens group comprising a fifth lens having a convex image side surface and a positive refractive power;
a fifth lens group comprising a sixth lens having a concave image side surface and a negative refractive power;
the third lens and the fourth lens satisfying the following condition:
20< Vd _ L 4− Vd _ L 3<40
where, Vd_L3 is Abbe number of the third lens and Vd_L4 is Abbe number of the fourth lens.
2. The camera lens system according to claim 1 satisfying the following condition:
−5.0< f 2.3/ f< 0
where,
f is the effective focal length of the entire lenses;
f23 is the synthetic effective focal length of the second lens group and the third lens group.
3. The camera lens system according to claim 1 satisfying the following condition:
0.80< TTL/ 2 y< 0.95
where
TTL is the distance from the object side surface of the first lens to the image side surface of the camera lens system;
y is half of the diagonal line length of the image side surface of the camera lens system.
4. The camera lens system according to claim 1 , wherein the third lens and the fourth lens satisfy following condition:
20< Vd _ L 3<30
50< Vd _ L 4<60
where, Vd_L3 is Abbe number of the third lens and Vd_L4 is Abbe number of the fourth lens.
5. The camera lens system according to claim 1 , wherein a cementing surface of the third lens and the fourth lens is spherical.