Lens assembly and electronic device including the same

1 . A lens assembly comprising:

an image sensor;

a first lens group;

a second lens group; and

a third lens group,

wherein the first lens group has a negative refractive power, and comprises at least two lenses disposed along an optical axis from the image sensor, and a first lens on an object side among the at least two lenses of the first lens group having a positive refractive power;

wherein the second lens group has a positive refractive power and is configured to move along the optical axis direction between the first lens group and the image sensor, the second lens group comprising at least two lenses, wherein at least one of the at least two lenses in the second lens group has a negative refractive power;

wherein the third lens group has a negative refractive power and is configured to move back and forth along the optical axis direction between the second lens group and the image sensor, the third lens group comprises a 3-1st lens having a positive refractive power and a 3-2nd lens having a negative refractive power and disposed between the 3-1st lens and the image sensor, and an air gap between the 3-1 st lens and the 3-2 nd lens,

wherein the lens assembly is configured to perform zooming, and wherein during zooming, as at least one of the second lens group and the third lens group moves toward an object side while the first lens group is static, a focal length of the lens assembly increases, and

wherein the lens assembly meets conditional equation 1 through conditional equation 4, wherein

-

1

.7

≤

fG

⁢

11

/

fG

⁢

1

≤

-

0.6

[

conditional

⁢

equation

⁢

1

]

-

3.2

≤

β

⁢

G

⁢

3

⁢

t

/

β

⁢

G

⁢

2

⁢

t

≤

-

2

[

conditional

⁢

equation

⁢

2

]

1.4

≤

❘

"\[LeftBracketingBar]"

fG

⁢

1

❘

"\[RightBracketingBar]"

/

fw

≤

2.5

[

conditional

⁢

equation

⁢

3

]

-

1.4

≤

fG

⁢

2

⁢

n

/

fG

⁢

2

≤

-

0.5

[

conditional

⁢

equation

⁢

4

]

wherein ‘fG11’ is a focal length of a first lens on the object side among lenses of the first lens group, ‘fG1’ is a focal length of the first lens group, ‘βG3t’ is an imaging magnification of the third lens group at a telephoto end, ‘βG2t’ is an imaging magnification of the second lens group at the telephoto end, ‘fw’ is a focal length of the lens assembly at a wide-angle end, ‘fG2n’ is a focal length of the at least one lens having a negative refractive power in the second lens group, and ‘fG2’ is a focal length of the second lens group.

2 . The lens assembly of claim 1 , further comprising a reflective member disposed on the object side of the first lens group,

wherein the reflective member is configured to guide or reflect light incident from an outside to the first lens group.

3 . The lens assembly of claim 1 , further comprising a reflective member disposed on the object side of the first lens group,

wherein the reflective member is configured to guide or reflect at least a portion of light incident from an outside to the first lens group.

4 . The lens assembly of claim 1 , wherein the lens assembly is configured so that the focal length of the lens assembly is adjusted as the second lens group moves along the optical axis direction and is configured so that a focus of the lens assembly is adjusted as the third lens group moves along the optical axis direction.

5 . The lens assembly of claim 1 , wherein the first lens group further comprises at least one second lens disposed between the first lens and the image sensor and having a negative refractive power.

6 . The lens assembly of claim 1 , wherein the second lens group includes at least one lens having a positive refractive power and at least one lens having a negative refractive power.

7 . The lens assembly of claim 1 , wherein at least one of the lenses in the first lens group or at least one of the lenses in the second lens group comprises glass.

8 . The lens assembly of claim 1 , further comprising an infrared cut filter disposed between the third lens group and the image sensor.

9 . The lens assembly of claim 1 wherein a focal length of the last lens in the first lens group is between −12 mm and −8 mm and a focal length of the last lens in the second lens group is between 9.5 mm and 11 mm.

10 . An electronic device comprising:

a processor; and

a lens assembly,

wherein the lens assembly includes,

an image sensor;

a first lens group;

a second lens group; and

a third lens group,

wherein the first lens group has a negative refractive power and includes at least two lenses disposed along an optical axis from the image sensor, and a first lens on an object side among the at least two lenses of the first lens group having a positive refractive power;

wherein the second lens group has a positive refractive power and is configured to move along an optical axis direction between the first lens group and the image sensor, the second lens group including at least two lenses, wherein at least one lens of the at least two lenses of the second lens group has a negative refractive power; and

wherein the third lens group has a negative refractive power and is configured to move back and forth along the optical axis direction between the second lens group and the image sensor, the third lens group comprises a 3-1 st lens having a positive refractive power and a 3-2nd lens having a negative refractive power and disposed between the 3-1st lens and the image sensor, and the 3-1 st lens has a surface facing the image sensor with a first radius of curvature, and wherein the 3-2 nd lens has a surface facing the object side having a second radius of curvature that is different from the first radius of curvature,

wherein the processor is configured to increase a focal length of the lens assembly by moving at least one of the second lens group and the third lens group toward an object side in a zooming operation while the first lens group is static,

wherein the lens assembly meets conditional equation 6 through conditional equation 9, wherein

-

1

.7

≤

fG

⁢

11

/

fG

⁢

1

≤

-

0.6

[

conditional

⁢

equation

⁢

6

]

-

3.2

≤

β

⁢

G

⁢

3

⁢

t

/

β

⁢

G

⁢

2

⁢

t

≤

-

2

[

conditional

⁢

equation

⁢

7

]

-

1.4

≤

fG

⁢

2

⁢

n

/

fG

⁢

2

≤

-

0.5

[

conditional

⁢

equation

⁢

8

]

1.4

≤

❘

"\[LeftBracketingBar]"

fG

⁢

1

❘

"\[RightBracketingBar]"

/

fw

≤

2.5

,

[

conditional

⁢

equation

⁢

9

]

and

wherein ‘fG11’ is a focal length of a first lens on the object side among lenses of the first lens group, ‘fG1’ is a focal length of the first lens group, ‘βG3t’ is an imaging magnification of the third lens group at a telephoto end, ‘βG2t’ is an imaging magnification of the second lens group at the telephoto end, ‘fG2n’ is a focal length of a lens having a negative refractive power in the second lens group, and ‘fG2’ is a focal length of the second lens group, and ‘fw’ is a focal length of the lens assembly at a wide-angle end.

11 . The electronic device of claim 10 , wherein the lens assembly further includes a reflective member disposed on the object side of the first lens group,

wherein the reflective member is configured to guide or reflect at least a portion of light incident from an outside to the first lens group.

12 . The electronic device of claim 10 , wherein the processor is configured to;

adjust the focal length of the lens assembly by moving the second lens group in the optical axis direction and

adjust a focus of the lens assembly by moving the third lens group in the optical axis direction.

13 . The electronic device of claim 10 , wherein the first lens group further comprises at least one second lens disposed between the first lens and the image sensor and having a negative refractive power.

14 . The electronic device of claim 10 , wherein the lens assembly further comprises an infrared cut filter disposed between the third lens group and the image sensor.