Optical system for vehicle and vehicle lamp using the same

1. An optical system comprising a plurality of lenses,

wherein a horizontal field of view and a vertical field of view of the optical system are different from each other, and an overall horizontal effective focal length (EFL) of the optical system and an overall vertical EFL of the optical system are different from each other,

wherein a first longitudinal section of the optical system in one of a horizontal direction or a vertical direction exhibits a retro-focus optical configuration, and a second longitudinal section of the optical system in the other of the horizontal direction or the vertical direction exhibits a telephoto optical configuration, and

wherein one or more surfaces of the optical system include a saddle shape which is vertically convex and horizontally concave or vertically concave and horizontally convex.

2. The optical system of claim 1 , wherein a ratio of the horizontal field of view to the vertical field of view is greater than 1:1 and less than or equal to 4:1.

3. The optical system of claim 1 , wherein the overall horizontal EFL of the optical system (F x ) and the overall vertical EFL of the optical system (F y ) satisfy an equation,

0.41

≤

F

x

F

y

≤

0.57

.

4. The optical system of claim 1 , wherein a horizontal EFL of lenses (f x ) except a lens closest to a light source and the overall horizontal EFL of the optical system (F x ) satisfy an equation,

1.63

≤

f

x

F

x

≤

2.49

.

5. The optical system of claim 1 , wherein a vertical EFL of lenses (f y ) except a lens closest to a light source, and the overall vertical EFL of the optical system (F y ) satisfy an equation,

1.5

≤

f

y

F

y

≤

2.49

.

6. The optical system of claim 1 , wherein a horizontal EFL of a lens closest to a light source (f fir_x ) and a vertical EFL of the lens closest to the light source (f fir_y ) satisfy an equation,

0.83

≤

f

fir_x

f

fir_y

≤

1.2

.

7. The optical system of claim 1 , wherein a numerical aperture (NA) is greater than or equal to 0.7.

8. The optical system of claim 1 , wherein an overall horizontal field of view of the optical system and an overall vertical field of view of the optical system are greater than or equal to 4 degrees and less than or equal to 20 degrees.

9. An optical system comprising a plurality of lenses,

wherein a horizontal field of view and a vertical field of view of the optical system are different from each other, and an overall horizontal effective focal length (EFL) of the optical system and an overall vertical EFL of the optical system are different from each other,

wherein a first longitudinal section of the optical system in one of a horizontal direction or a vertical direction exhibits a retro-focus optical configuration, and a second longitudinal section of the optical system in the other of the horizontal direction or the vertical direction exhibits a telephoto optical configuration,

wherein a distortion is generated such that a pixel size of an image formed by light that passes through the plurality of lenses gradually increases or decreases from a center toward an edge to be distorted,

wherein in the distortion, a horizontal distortion level and a vertical distortion level are different from each other, and

wherein an anamorphic surface of the optical system from which the light is emitted includes a saddle shape which is horizontally concave and vertically convex or horizontally convex and vertically concave.

10. The optical system of claim 9 , wherein the pixel size of the image gradually increases or decreases toward lateral or vertical edges.

11. The optical system of claim 9 , wherein the distortion is generated based on the shape of the anamorphic surface of the optical system.

12. The optical system of claim 9 , wherein a horizontal curvature of the anamorphic surface (c las_x ) and a vertical curvature of the anamorphic surface (c las_y ) of the optical system satisfy an equation,

-

18.4

≤

c

las_x

c

las_y

≤

6.3

.

13. The optical system of claim 9 , wherein the anamorphic surface (las) of the optical system satisfies an equation,

-

5767.4

≤

z

las_x

z

las_y

≤

256.8

,

z

=

1

2

⁢

c

·

s

0.1

2

wherein x denotes the horizontal direction and y denotes a vertical direction.

14. The optical system of claim 9 , wherein the anamorphic surface (las) of the optical system satisfies an equation,

0.7

×

10

-

9

≤

K

las_x

⁢

c

las_x

3

D

las

4

≤

1.65

×

10

-

8

,

wherein K is a conic constant, c is curvature, and D is a diameter of a lens with the anamorphic surface, and

wherein x denotes the horizontal direction and y denotes the vertical direction.

15. The optical system of claim 9 , wherein the anamorphic surface (las) of the optical system satisfies an equation,

0.7

×

10

-

10

≤

8

⁢

A

las_x

D

las

4

≤

1.3

×

10

-

9

,

wherein A is an aspherical fourth-order constant, and D is a diameter of a lens with the anamorphic surface, and

wherein x denotes the horizontal direction and y denotes a vertical direction.

16. The optical system of claim 9 , wherein the anamorphic surface (las) of the optical system satisfies an equation,

4.5

≤

K

las

⁢

_

⁢

x

⁢

c

las_x

3

+

8

⁢

A

las_x

K

las

⁢

_

⁢

y

⁢

c

las_y

3

+

8

⁢

A

las_y

≤

210

,

wherein K is a conic constant, c is curvature, and A is an aspherical fourth-order constant, and

wherein x denotes the horizontal direction and y denotes a vertical direction.

17. The optical system of claim 9 , wherein a thickness of a first lens of the optical system (d first ) and a diameter of the lens (D first ) satisfy an equation,

0.75

≤

d

first

D

first

≤

1.45

.

18. The optical system of claim 9 , wherein a first lens of the optical system on which the light is incident has an Abbe number that is greater than or equal to 45.

19. The optical system of claim 9 , wherein a mean refractive index of all lenses included in the optical system is equal to or greater than 1.6 and equal to or less than 1.8.

20. A vehicle lamp comprising:

a light source; and

optical lenses comprising a plurality of lenses and transmitting light emitted by the light source,

wherein in the optical lenses, a horizontal field of view and a vertical field of view are different from each other, and a horizontal effective focal length (EFL) and a vertical EFL are different from each other,

wherein a first longitudinal section of the optical system in one of a horizontal direction or a vertical direction exhibits a retro-focus optical configuration, and a second longitudinal section of the optical system in the other of the horizontal direction or the vertical direction exhibits a telephoto optical configuration, and

wherein one or more surfaces of the optical lens include a saddle shape which is vertically convex and horizontally concave or vertically concave and horizontally convex.

21. The optical system of claim 20 , wherein a distortion is generated such that a pixel size of an image, on which light that passes through the optical lenses and is emitted is formed, gradually increases or decreases from a center toward an edge to be distorted, and

wherein in the distortion, a horizontal distortion level and a vertical distortion level are different from each other.