Image capturing optical system
Disclosed is an image capturing optical system including, in order from an object side, a first lens having positive refractive power and concave upwards, a second lens having positive refractive power, a third lens having negative refractive power, a fourth lens having positive refractive power, a fifth lens having positive refractive power and including at least one inflection points on the object side or an upper surface, and a sixth lens having negative refractive power and being convex upwards.
1. An image capturing optical system, comprising:
in order from an object side,
a first lens having positive refractive power and including a convex object side surface and a concave image side surface;
a second lens having positive refractive power and including a convex object side surface and a convex image side surface;
a third lens having negative refractive power including a convex object side surface and a concave image side surface;
a fourth lens having positive refractive power including a concave object side surface and a convex image side surface;
a fifth lens having positive refractive power and including a convex object side surface and a concave image side surface; and
a sixth lens having negative refractive power and including a concave object side surface and a convex image side surface,
wherein the image capturing optical system satisfies the following:
1.5< f/f 2 <2.5, and
4.5< OTL 5/ CT 5<10.0,
wherein f is a focal length of the image capturing optical system, f 2 is a focal length of the second lens, OTL5 is a distance on an optical axis from the convex object side surface of the first lens to the concave image side surface of the fifth lens, and CT5 is a thickness of a center of the fifth lens.
2. The image capturing optical system of claim 1 , wherein the image capturing optical system satisfies the following inequality:
0.45<| f 2 /f 3 |<1.0
wherein f 3 is a focal length of the third lens.
3. The image capturing optical system of claim 1 , wherein the image capturing optical system satisfies the following Equation:
0.35<| Vd 3 /Vd 4 |=1
wherein Vd 3 is an Abbe number of the third lens, and Vd 4 is an Abbe number of the fourth lens.
4. The image capturing optical system of claim 1 , further comprising an optical filter between the sixth lens and an image sensor.
5. An image capturing optical system, comprising:
in order from an object side,
a first lens having negative refractive power and including a convex object side surface and a concave image side surface;
a second lens having positive refractive power and including a convex object side surface and a convex image side surface;
a third lens having negative refractive power including a convex object side surface and a concave image side surface;
a fourth lens having positive refractive power including a concave object side surface and a convex image side surface;
a fifth lens having positive refractive power and including a convex object side surface and a concave image side surface; and
a sixth lens having negative refractive power and including a concave object side surface and a convex image side surface,
wherein the image capturing optical system satisfies the following:
1.5< f/f 2 <2.5, and
4.5< OTL 5/ CT 5<10.0,
wherein f is a focal length of the image capturing optical system, f 2 is a focal length of the second lens, OTL5 is a distance on an optical axis from the convex object side surface of the first lens to the concave image side surface of the fifth lens, and CT5 is a thickness of a center of the fifth lens.
6. The image capturing optical system of claim 5 , wherein the image capturing optical system satisfies the following Inequality:
0.45<| f 2 /f 3 |<1.0
wherein f 2 is a focal length of the second lens, and f 3 is a focal length of the third lens.
7. The image capturing optical system of claim 5 , wherein the image capturing optical system satisfies the following Equation:
0.35<| Vd 3 /Vd 4 |=1
wherein Vd 3 is an Abbe number of the third lens, and Vd 4 is an Abbe number of the fourth lens.
8. The image capturing optical system of claim 5 , further comprising an optical filter between the sixth lens and an image sensor.
9. An image capturing optical system, comprising:
in order from an object side,
a first lens having positive or negative refractive power and including a convex object side surface and a concave image side surface;
a second lens having positive refractive power and including a convex object side surface and a convex image side surface;
a third lens having negative refractive power including a convex object side surface and a concave image side surface;
a fourth lens having positive refractive power including a concave object side surface and a convex image side surface;
a fifth lens having positive refractive power and including a convex object side surface and a concave image side surface; and
a sixth lens having negative refractive power and including a concave object side surface and a convex image side surface, wherein the image capturing optical system satisfies the following:
0.45<| f 2 /f 3 |<1.0,
1.5< f/f 2 <2.5,
4.5< OTL 5/ CT 5<10.0, and
0.35<| Vd 3 /Vd 4 |=1
wherein f is a focal length of the image capturing optical system, f 2 is a focal length of the second lens, f 3 is a focal length of the third lens, OTL5 is a distance on an optical axis from the convex object side surface of the first lens to of the concave image side surface of the fifth lens, CT5 is a thickness of a center of the fifth lens, Vd 3 is an Abbe number of the third lens, and Vd 4 is an Abbe number of the fourth lens.