Zoom lens and electronic device including the same

Patent metadata

Field	Value
Publication number	US-9435987-B2
Application number	US-201414306739-A
Country	US
Kind code	B2
Filing date	Jun 17, 2014
Priority date	Jul 9, 2013
Publication date	Sep 6, 2016
Grant date	Sep 6, 2016

Abstract

A zoom lens that includes, in order from an object side to an image side, a first lens group having a negative refractive power, a second lens group having a positive refractive power, a third lens group having a positive refractive power, and a fourth lens group having a positive refractive power, and when zooming from a wide angle position to a telephoto position, an interval between the first lens group and the second lens group decreases, an interval between the second lens group and the third lens group decreases, and an interval between the third lens group and the fourth lens group increases.

First claim

What is claimed is:

1. A zoom lens comprising, in order from an object side to an image side:
a first lens group having a negative refractive power;
a second lens group having a positive refractive power;
a third lens group having a positive refractive power; and
a fourth lens group having a positive refractive power,
wherein when zooming from a wide angle position to a telephoto position, an interval between the first lens group and the second lens group decreases, an interval between the second lens group and the third lens group decreases, and an interval between the third lens group and the fourth lens group increases,
wherein the second lens group comprises, in a sequence from the object side, a positive lens, a positive lens, a positive lens, and a negative lens, and
wherein the zoom lens satisfies the following expression:
0.3≦wFno*fw/f2≦1.25

where, f2 denotes a focal length of the second lens group, fw denotes a focal length of the zoom lens at the wide angle position, and wFno denotes an F number at the wide angle position.

2. The zoom lens of claim 1 , wherein the first lens group comprises one or more negative lenses, and at least one of the one or more negative lenses satisfies the following expression:
60≦1Vd≦100

where, 1Vd denotes an Abbe number of at least one of the one or more negative lenses of the first lens group.

3. The zoom lens of claim 1 , wherein the zoom lens satisfies the following expression:
1.7≦f3/fw≦21.5

where, f3 denotes a focal length of the third lens group, and fw denotes a focal length of the zoom lens at the wide angle position.

4. The zoom lens of claim 1 , wherein the fourth lens group satisfies the following expression:
2.9≦f4/ fw≦ 12

where, f4 denotes a focal length of the fourth lens group, and fw denotes a focal length of the zoom lens at the wide angle position.

5. The zoom lens of claim 1 , wherein the first lens group comprises a positive lens, and a refractive index of the positive lens satisfies the following expression:
1.9≦1Nd

where, 1Nd denotes a d-line refractive index of the positive lens of the first lens group.

6. The zoom lens of claim 1 , wherein the second lens group comprises an aspherical lens having a meniscus shape with a convex surface facing toward the object side.

7. The zoom lens of claim 1 , wherein the second lens group comprises a cemented lens.

8. The zoom lens of claim 1 , wherein the third lens group comprises an aspherical lens having a positive refractive power.

9. The zoom lens of claim 1 , wherein the third lens group performs correction of vibration.

10. The zoom lens of claim 1 , wherein the third lens group comprises an aperture diaphragm.

11. The zoom lens of claim 10 , wherein the third lens group and the aperture diaphragm move in a same trajectory during zooming.

12. The zoom lens of claim 1 , wherein the first lens group comprises a first negative lens, a second negative lens, and a positive lens.

13. The zoom lens of claim 12 , wherein the first negative lens of the first lens group is an aspherical lens.

14. The zoom lens of claim 1 , wherein the third lens group comprises a negative lens and a positive lens.

15. The zoom lens of claim 1 , wherein the third lens group comprises one positive lens.

16. The zoom lens of claim 1 , wherein the fourth lens group comprises an aspherical lens having a positive refractive power.

17. The zoom lens of claim 1 , wherein the fourth lens group comprises a meniscus lens with a convex surface facing toward the object side.

18. The zoom lens of claim 1 , wherein the fourth lens group performs focusing.

19. A photographing device comprising:
a zoom lens; and
an imaging element that receives an image formed by the zoom lens,
wherein the zoom lens comprises, in order from an object side to an image side, a first lens group having a negative refractive power, a second lens group having a positive refractive power, a third lens group having a positive refractive power, and a fourth lens group having a positive refractive power,
wherein when zooming from a wide angle position to a telephoto position, an interval between the first lens group and the second lens group decreases, an interval between the second lens group and the third lens group decreases, and an interval between the third lens group and the fourth lens group increases,
wherein the second lens group comprises, in a sequence from the object side, a positive lens, a positive lens, a positive lens, and a negative lens, and
wherein the zoom lens satisfies the following expression:
0.3≦wFno*fw/f2≦1.25

where, f2 denotes a focal length of the second lens group, fw denotes a focal length of the zoom lens at the wide angle position, and wFno denotes an F number at the wide angle position.

20. The photographing device of claim 19 , wherein the first lens group comprises one or more negative lenses, and at least one of the one or more negative lenses satisfies the following expression:
60≦1Vd≦100

where, 1Vd denotes an Abbe number of at least one of the one or more negative lenses of the first lens group.

21. The photographing device of claim 19 , wherein the zoom lens satisfies the following expression:
1.7≦f3/fw≦21.5

where, f3 denotes a focal length of the third lens group, and fw denotes a focal length of the zoom lens at the wide angle position.

Assignees

• Samsung Electronics Co Ltd

Inventors

• Kim Jin-Woo

Classifications

• H04N23/55

  Optical parts specially adapted for electronic image sensors; Mounting thereof · CPC title

• G02B27/646 Primary

  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 title

• G02B9/34

  having four components only · CPC title

• G02B15/177 Primary

  having a negative front lens or group of lenses · CPC title

• G02B13/009

  having zoom function · CPC title