Lens module
There is provided a lens module including: a first lens having positive refractive power; a second lens having positive refractive power; a third lens having a shape in which an object-side surface thereof is concave; a fourth lens having refractive power; a fifth lens having negative refractive power; and a sixth lens having negative refractive power, having a shape in which an image-side surface thereof is concave, and having at least one point of inflection formed on the image-side surface thereof.
1. A lens module comprising:
a first lens having positive refractive power;
a second lens having positive refractive power;
a third lens having a shape in which an object-side surface thereof is concave;
a fourth lens having refractive power of which an object-side surface is convex;
a fifth lens having negative refractive power; and
a sixth lens having negative refractive power, having a shape in which an image-side surface thereof is concave, and having at least one point of inflection formed on the image-side surface thereof.
2. The lens module of claim 1 , wherein an optical system including the first to sixth lenses satisfies Conditional Equation 1:
0.3 <f 12 /f 0.8 [Conditional Equation 1]
where f 12 is a composite focal length of the first and second lenses and f indicates an overall focal length of the optical system.
3. The lens module of claim 1 , wherein an optical system including the first to sixth lenses satisfies Conditional Equation 2:
( EPD /2) /f 12<0.6 [Conditional Equation 2]
where EPD indicates an entrance pupil diameter and f 12 is a composite focal length of the first and second lenses.
4. The lens module of claim 1 , wherein an optical system including the first to sixth lenses satisfies Conditional Equation 3:
f 5 /f<− 3.0 [Conditional Equation 3]
where f 5 indicates a focal length of the fifth lens and f indicates an overall focal length of the optical system.
5. The lens module of claim 1 , wherein an optical system including the first to sixth lenses satisfies Conditional Equation 4:
| V 1 −V 5|>25 [Conditional Equation 4]
where V 1 indicates an Abbe number of the first lens, and V 5 indicates an Abbe number of the fifth lens.
6. The lens module of claim 1 , wherein an optical system including the first to sixth lenses satisfies Conditional Equation 5:
TTL/f< 1.4 [Conditional Equation 5]
where TTL indicates a distance from an object-side surface of the first lens to an image surface.
7. The lens module of claim 1 , wherein an optical system including the first to sixth lenses satisfies Conditional Equation 6:
0.5< f 1 /f 2<2.2 [Conditional Equation 6]
where f 1 indicates a focal length of the first lens and f 2 indicates a focal length of the second lens.
8. The lens module of claim 1 , wherein an optical system including the first to sixth lenses satisfies Conditional Equation 7:
BFL/f >0.15 [Conditional Equation 7]
where BFL indicates a distance from the image-side surface of the sixth lens to an image surface and f indicates an overall focal length of the optical system.
9. The lens module of claim 1 , wherein an optical system including the first to sixth lenses satisfies Conditional Equation 8:
r 1 /f> 0.2 [Conditional Equation 8]
where r 1 indicates a radius of curvature of an object-side surface of the first lens and f indicates an overall focal length of the optical system.
10. The lens module of claim 1 , wherein an optical system including the first to sixth lenses satisfies Conditional Equation 9:
( r 5+ r 6)/( r 5− r 6)>( r 7+ r 8)/( r 7− r 8) [Conditional Equation 9]
where r 5 and r 6 indicate radii of curvature of the object-side surface and an image-side surface of the third lens, respectively, and r 7 and r 8 indicate radii of curvature of an object-side surface and an image-side surface of the fourth lens, respectively.
11. A lens module comprising:
a first lens having positive refractive power;
a second lens having positive refractive power;
a third lens having negative refractive power;
a fourth lens having refractive power and having a shape in which an object-side surface thereof is convex;
a fifth lens having negative refractive power; and
a sixth lens having negative refractive power, having a shape in which an image-side surface thereof is concave, and having at least one point of inflection formed on the image-side surface thereof.
12. The lens module of claim 11 , wherein the first lens has a meniscus shape in which it is convex toward an object.
13. The lens module of claim 11 , wherein the second lens has a shape in which both surfaces thereof are convex.
14. The lens module of claim 11 , wherein the third lens has a shape in which both surfaces thereof are concave.
15. The lens module of claim 11 , wherein the fourth lens has positive refractive power.
16. The lens module of claim 11 , wherein the fifth lens has a meniscus shape in which it is convex toward an image.
17. The lens module of claim 11 , wherein the sixth lens has a shape in which an object-side surface thereof is convex and the image-side surface thereof is concave.
18. The lens module of claim 11 , wherein an optical system including the first to sixth lenses satisfies Conditional Equation 1:
0.3 <f 12 /f 0.8 [Conditional Equation 1]
where f 12 is a composite focal length of the first and second lenses and f indicates an overall focal length of the optical system.
19. The lens module of claim 11 , wherein an optical system including the first to sixth lenses satisfies Conditional Equation 2:
( EPD/ 2)/ f 12<0.6 [Conditional Equation 2]
where EPD indicates an entrance pupil diameter and f 12 is a composite focal length of the first and second lenses.
20. The lens module of claim 11 , wherein an optical system including the first to sixth lenses satisfies Conditional Equation 3:
f 5 /f<− 3.0 [Conditional Equation 3]
where f 5 indicates a focal length of the fifth lens and f indicates an overall focal length of the optical system.
21. The lens module of claim 11 , wherein an optical system including the first to sixth lenses satisfies Conditional Equation 4:
| V 1− V 5|>25 [Conditional Equation 4]
where V 1 indicates an Abbe number of the first lens, and V 5 indicates an Abbe number of the fifth lens.
22. The lens module of claim 11 , wherein an optical system including the first to sixth lenses satisfies Conditional Equation 5:
TTL/f< 1.4 [Conditional Equation 5]
where TTL indicates a distance from an object-side surface of the first lens to an image surface.
23. The lens module of claim 11 , wherein an optical system including the first to sixth lenses satisfies Conditional Equation 6:
0.5< f 1 /f 2<2.2 [Conditional Equation 6]
where f 1 indicates a focal length of the first lens and f 2 indicates a focal length of the second lens.
24. The lens module of claim 11 , wherein an optical system including the first to sixth lenses satisfies Conditional Equation 7:
BFL/f> 0.15 [Conditional Equation 7]
where BFL indicates a distance from the image-side surface of the sixth lens to an image surface and f indicates an overall focal length of the optical system.
25. The lens module of claim 11 , wherein an optical system including the first to sixth lenses satisfies Conditional Equation 8:
r 1/ f> 0.2 [Conditional Equation 8]
where r 1 indicates a radius of curvature of an object-side surface of the first lens and f indicates an overall focal length of the optical system.
26. The lens module of claim 11 , wherein an optical system including the first to sixth lenses satisfies Conditional Equation 9:
( r 5+ r 6)/( r 5− r 6)>( r 7+ r 8)/( r 7− r 8) [Conditional Equation 9]
where r 5 and r 6 indicate radii of curvature of an object-side surface and an image-side surface of the third lens, respectively, and r 7 and r 8 indicate radii of curvature of the object-side surface and an image-side surface of the fourth lens, respectively.