Optical photographing assembly, image capturing apparatus, and electronic device comprising five-lens system having inflection point

• US 10,386,605 B2
• Filed: 10/18/2016
• Issued: 08/20/2019
• Est. Priority Date: 07/14/2016
• Status: Active Grant

• Current Assignee: Largan Precision Co Limited (Largan Precision)
• Original Assignee: Largan Precision Co Limited (Largan Precision)
• Inventors: Chen, Chun-Yen
• Primary Examiner(s): Allen, Stephone B
• Assistant Examiner(s): Dunning, Ryan S
• Application Number:
  US15/296,149
• Publication Number:
  US 20180017767A1
• Time in Patent Office: 1,036 Days
• Field of Search: 359708, 359714, 359746, 359763-766
• CPC Class Codes: G02B 13/0045 having five or more lenses
• CPC Class Codes: G02B 13/0065 having a beam-folding prism or mirror
• CPC Class Codes: G02B 27/646 compensating for small deviations, e.g. due to vibration or shake movement of one or more optical elements for control of motion blur in cameras, projectors or printers G03B2205/0007; image stabilisation in cameras peculiar to the presence or use of an electronic image sensor H04N23/68
• CPC Class Codes: G02B 9/60 having five components only
• CPC Class Codes: G02B 9/62 having six components only
• CPC Class Codes: G02B 9/64 having more than six components

Abstract

An optical photographing assembly includes, in order from an object side to an image side along an optical axis, a first lens element, a second lens element, a third lens element, a fourth lens element and a fifth lens element. The first lens element has positive refractive power. The third lens element has at least one of an object-side surface and an image-side surface being aspheric. The fourth lens element has at least one of an object-side surface and an image-side surface being aspheric. The fifth lens element has at least one of an object-side surface and an image-side surface being aspheric, wherein at least one of the object-side surface and the image-side surface of the fifth lens element includes at least one inflection point.

Claims

1. An optical photographing assembly comprising, in order from an object side to an image side along an optical axis:

a first lens element having positive refractive power;

a second lens element having negative refractive power;

a third lens element having at least one of an object-side surface and an image-side surface being aspheric;

a fourth lens element having at least one of an object-side surface and an image-side surface being aspheric; and

a fifth lens element having at least one of an object-side surface and an image-side surface being aspheric, wherein at least one of the object-side surface and the image-side surface of the fifth lens element comprises at least one inflection point;

wherein the optical photographing assembly has a total of five lens elements, there is an air space between every two lens elements of the first lens element, the second lens element, the third lens element, the fourth lens element and the fifth lens element that are adjacent to each other, a maximum field of view of the optical photographing assembly is FOV, an axial distance between an image-side surface of one lens element closest to an image surface and the image surface is BL, an axial distance between an object-side surface of one lens element closest to an imaged object and the image-side surface of the lens element closest to the image surface is TD, an axial distance between the second lens element and the third lens element is T23, a central thickness of the first lens element is CT1, a focal length of the optical photographing assembly is f, a curvature radius of the object-side surface of the fourth lens element is R7, and the following conditions are satisfied;

0.10<

tan(FOV)<

0.85;

0.75<

BL/TD<

1.50;

0<

T23/CT1<

0.60; and

−

9.50<

f/R7<

1.50.

2. The optical photographing assembly of claim 1, wherein the focal length of the optical photographing assembly is f, the axial distance between the object-side surface of the lens element closest to the imaged object and the image-side surface of the lens element closest to the image surface is TD, and the following condition is satisfied:

1.50<

f/TD<

2.50.

3. The optical photographing assembly of claim 1, further comprising:

an aperture stop, wherein an axial distance between the aperture stop and the image-side surface of the lens element closest to the image surface is SD, the axial distance between the object-side surface of the lens element closest to the imaged object and the image-side surface of the lens element closest to the image surface is TD, and the following condition is satisfied;

0.80<

SD/TD<

1.10.

4. The optical photographing assembly of claim 1, wherein the first lens element has an object-side surface being convex, and the image-side surface of the fifth lens element is concave.

5. The optical photographing assembly of claim 1, wherein the third lens element has positive refractive power, and the fourth lens element has negative refractive power.

6. The optical photographing assembly of claim 1, wherein the focal length of the optical photographing assembly is f, a focal length of the fourth lens element is f4, a focal length of the fifth lens element is f5, and the following conditions are satisfied:

−

1.0<

f/f4<

1.0; and

−

1.0<

f/f5<

1.0.

7. The optical photographing assembly of claim 1, wherein a focal length of the first lens element is f1, a focal length of the second lens element is f2, the focal length of the optical photographing assembly is f, the axial distance between the object-side surface of the lens element closest to the imaged object and the image-side surface of the lens element closest to the image surface is TD, and the following conditions are satisfied:

|f1/f2|<

1.0; and

1.72<

f/TD<

2.20.

8. The optical photographing assembly of claim 1, wherein a sum of thicknesses of the lens elements of the optical photographing assembly is Σ

CT, a sum of axial distances between every two of the lens elements of the optical photographing assembly that are adjacent to each other is EAT, and the following condition is satisfied;

3.0<

Σ

CT/Σ

AT<

5.0.

9. The optical photographing assembly of claim 1, wherein the central thickness of the first lens element is CT1, a sum of thicknesses of the lens elements of the optical photographing assembly is Σ

CT, and the following condition is satisfied;

0.50<

CT1/(Σ

CT−

CT1)<

1.80.

10. The optical photographing assembly of claim 1, wherein an Abbe number of the second lens element is V2, an Abbe number of the third lens element is V3, an Abbe number of the fourth lens element is V4, and the following conditions are satisfied:

V2<

27.0;

V3<

27.0; and

V4<

27.0.

11. The optical photographing assembly of claim 1, wherein an effective radius of a lens surface closest to the imaged object is Yo, an effective radius of a lens surface closest to the image surface is Yi, and the following condition is satisfied:

0.95<

Yo/Yi<

1.15.

12. The optical photographing assembly of claim 1, wherein a maximum among effective radii of object-side and image-side surfaces of the lens elements of the optical photographing assembly is Ymax, a minimum among effective radii of the object-side and the image-side surfaces of the lens elements of the optical photographing assembly is Ymin, and the following condition is satisfied:

1.0<

Ymax/Ymin<

1.50.

13. The optical photographing assembly of claim 1, further comprising:

an aperture stop, wherein an axial distance between an object-side surface of the first lens element and the aperture stop is Dr1s, an axial distance between an image-side surface of the first lens element and the aperture stop is Dr2s, and the following condition is satisfied;

0<

|Dr1s/Dr2s|<

1.0.

14. The optical photographing assembly of claim 1, wherein a curvature radius of an object-side surface of the second lens element is R3, a curvature radius of an image-side surface of the second lens element is R4, and the following condition is satisfied:

−

1.5<

(R3−

R4)/(R3+R4)<

0.

15. The optical photographing assembly of claim 1, wherein a curvature radius of the object-side surface of the third lens element is R5, a curvature radius of the image-side surface of the third lens element is R6, the axial distance between the second lens element and the third lens element is T23, the central thickness of the first lens element is CT1, the focal length of the optical photographing assembly is f, the curvature radius of the object-side surface of the fourth lens element is R7, and the following conditions are satisfied:

−

2.0<

(R5+R6)/(R5−

R6)<

1.0;

0<

T23Σ

CT1<

0.25; and

−

6.50<

f/R7<

0.50.

16. The optical photographing assembly of claim 1, wherein the focal length of the optical photographing assembly is f, a maximum image height of the optical photographing assembly is ImgH, and the following condition is satisfied:

3.0<

f/ImgH<

6.0.

17. The optical photographing assembly of claim 1, wherein the first lens element is a movable focusing lens element, there is a relative displacement between the first lens element and the second lens element, and it is relatively stationary between every two of the second lens element, the third lens element, the fourth lens element and the fifth lens element;

wherein an axial distance between the first lens element and the second lens element with an object distance at infinity is T12i, an axial distance between the first lens element and the second lens element with the object distance at 400 mm is T12m, and the following condition is satisfied;

0.50<

T12i/T12m<

0.95.

18. The optical photographing assembly of claim 1, further comprising:

at least one prism on the optical axis.

19. The optical photographing assembly of claim 18, wherein the axial distance between the object-side surface of the lens element closest to the imaged object and the image-side surface of the lens element closest to the image surface is TD, a sum of light path lengths on the optical axis in the at least one prism is TP, and the following condition is satisfied:

0.80<

TD/TP<

1.25.

20. The optical photographing assembly of claim 18, wherein the prism is disposed at the object side of the first lens element or at the image side of the fifth lens element.

21. An image capturing apparatus, comprising:

the optical photographing assembly of claim 1; and

an image sensor, wherein the image sensor is disposed on the image surface of the optical photographing assembly.

22. An electronic device, comprising:

the image capturing apparatus of claim 21.