Optical imaging system

• US 9,952,409 B2
• Filed: 06/21/2016
• Issued: 04/24/2018
• Est. Priority Date: 10/19/2015
• Status: Active Grant

• Current Assignee: Samsung Electro-Mechanics Co., Ltd. (Samsung Group)
• Original Assignee: Samsung Electro-Mechanics Co., Ltd. (Samsung Group)
• Inventors: Lee, Tae Youn
• Primary Examiner(s): CHOI, WILLIAM C
• Application Number:
  US15/187,918
• Publication Number:
  US 20170108666A1
• Time in Patent Office: 672 Days
• Field of Search: 359713, 359752, 359756, 359761, 359762
• CPC Class Codes: G02B 13/0045 having five or more lenses
• CPC Class Codes: G02B 9/62 having six components only

Abstract

There is provided an optical imaging system including a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens. The first lens includes a negative refractive power and a concave object-side surface. The second lens includes a concave object-side surface. The fourth lens includes a negative refractive power. The sixth lens includes an inflection point formed on an image-side surface thereof. The first to sixth lenses are sequentially disposed from an object side toward an imaging plane.

Claims

1. An optical imaging system, comprising:

a first lens comprising a negative refractive power and a concave object-side surface;

a second lens comprising a concave object-side surface;

a third lens;

a fourth lens comprising a negative refractive power and a convex object-side surface;

a fifth lens; and

a sixth lens comprising an inflection point formed on an image-side surface thereof,

wherein the first to sixth lenses are sequentially disposed from an object side toward an imaging plane.

2. The optical imaging system of claim 1, wherein the second lens comprises a positive refractive power.

3. The optical imaging system of claim 1, wherein the third lens comprises a positive refractive power.

4. The optical imaging system of claim 1, wherein the fifth lens comprises a positive refractive power.

5. The optical imaging system of claim 1, wherein the sixth lens comprises a negative refractive power.

6. The optical imaging system of claim 1, wherein −

35.0<

{(1/f)*(Y/tan θ

)−

1}*100<

−

5.0, in which f is an overall focal length of the optical imaging system, Y is ½

of a diagonal length of the imaging plane, and θ

is equal to half a field of view of the optical imaging system.

7. The optical imaging system of claim 1, wherein TL/2Y<

0.95, in which TL is a distance from the object-side surface of the first lens to the imaging plane, and 2Y is a diagonal length of the imaging plane.

8. The optical imaging system of claim 1, wherein R1/f<

−

0.5, in which f is an overall focal length of the optical imaging system, and R1 is a radius of curvature of the object-side surface of the first lens.

9. The optical imaging system of claim 1, wherein −

5.5<

(R1+R2)/(R1−

R2)<

0.5, in which R1 is a radius of curvature of the object-side surface of the first lens, and R2 is a radius of curvature of an image-side surface of the first lens.

10. The optical imaging system of claim 1, wherein −

1.5<

f/f1<

−

0.05, in which f is an overall focal length of the optical imaging system, and f1 is a focal length of the first lens.

11. The optical imaging system of claim 1, wherein 0.5<

f/f3<

2.0, in which f is an overall focal length of the optical imaging system, and f3 is a focal length of the third lens.

12. The optical imaging system of claim 1, wherein 0.7<

|f/f6|<

1.8, in which f is an overall focal length of the optical imaging system, and f6 is a focal length of the sixth lens.

13. The optical imaging system of claim 1, wherein 1.5<

f/EPD<

2.1, in which f is an overall focal length of the optical imaging system, and EPD is an entrance pupil diameter of the optical imaging system.

14. The optical imaging system of claim 1, wherein 0.4<

(t1+t2)/t3<

1.3, in which t1 is a thickness at an optical axis center of the first lens, t2 is a thickness at an optical axis center of the second lens, and t3 is a thickness at an optical axis center of the third lens.

15. The optical imaging system of claim 1, wherein 0<

|n1−

n2|<

0.25, in which n1 is a refractive index of the first lens, and n2 is a refractive index of the second lens.