Optical imaging system
An optical imaging system includes a first lens group and a second lens group. The first lens group includes a first lens and a second lens. The second lens group includes a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens. The first to seventh lenses are sequentially disposed from an object side toward an imaging plane. The optical imaging system satisfies TTL/2Y<1.3, where TTL is a distance from an object-side surface of the first lens to the imaging plane, and 2Y is a diagonal length of the imaging plane.
1. An optical imaging system comprising:
a first lens comprising negative refractive power;
a second lens comprising a convex object-side surface;
a third lens comprising positive refractive power and a convex image-side surface;
a fourth lens comprising a refractive power;
a fifth lens comprising a convex image-side surface;
a sixth lens comprising a convex object-side surface; and
a seventh lens comprising a convex object-side surface,
wherein the first to seventh lenses are sequentially disposed from an object side toward an image plane, and
wherein TTL/2Y<1.3 is satisfied, where TTL is a distance from an object-side surface of the first lens to the imaging plane, and 2Y is a diagonal length of the imaging plane.
2. The optical imaging system of claim 1 , wherein the second lens has positive refractive power.
3. The optical imaging system of claim 1 , wherein the fourth lens has negative refractive power.
4. The optical imaging system of claim 1 , wherein the fifth lens has positive refractive power.
5. The optical imaging system of claim 1 , wherein the sixth lens has negative refractive power.
6. The optical imaging system of claim 1 , wherein the first lens has a concave image-side surface.
7. The optical imaging system of claim 1 , wherein the third lens has a convex object-side surface.
8. The optical imaging system of claim 1 , wherein the fourth lens has a concave object-side surface.
9. The optical imaging system of claim 1 , wherein the fourth lens has a concave image-side surface.
10. The optical imaging system of claim 1 , wherein the seventh lens has a concave image-side surface.
11. The optical imaging system of claim 1 , wherein −1.5<f/f1<−0.05 is satisfied, where f is an overall focal length of the optical imaging system, and f1 is a focal length of the first lens.
12. The optical imaging system of claim 1 , wherein 0.3<f/f2<0.8 is satisfied, where f is an overall focal length of the optical imaging system, and f2 is a focal length of the second lens.