Imaging optics and imaging device

Patent metadata

Field	Value
Publication number	US-2020355889-A1
Application number	US-201916716715-A
Country	US
Kind code	A1
Filing date	Dec 17, 2019
Priority date	May 10, 2019
Publication date	Nov 12, 2020
Grant date	—

Abstract

An imaging optics including, in sequence starting from the object side, of a 1st lens G1 with a negative refractive power, a 2nd lens G2 with a positive refractive power, a 3rd lens G3 with a positive refractive power, and a 4th lens G4, a 5th lens G5, a 6th lens G6, and a 7th lens G7 with a negative refractive power, satisfying the conditional expressions.

First claim

What is claimed is:

1 . An imaging optics comprising, in sequence starting from the object side, of a 1st lens with a negative refractive power, a 2nd lens with a positive refractive power, a 3rd lens with a positive refractive power, and a 4th lens, a 5th lens, a 6th lens, and a 7th lens with a negative refractive power, satisfying the following conditional expressions
0.50≤ f 2/ f≤ 1.15  (1-1)
0.38≤ f 3/ f≤ 1.10  (1-2)
0.015≤ thi _max/ oal≤ 0.210  (1-3)
where: f: focal length of the imaging optics f2: focal length of the 2nd lens f3: focal length of the 3rd lens thi_max: maximum lens spacing excluding back focal length oal: optical length of the imaging optics from the object side surface of the 1st lens to imaging surface.

2 . The imaging optics of claim 1 , wherein the following conditional expression is satisfied
0.50≤| f 1|/ f≤ 1.71  (2)
where: f1: focal length of the 1st lens.

3 . The imaging optics of claim 1 , wherein the following conditional expression is satisfied
0.38≤| f 4|/ f≤ 1.32  (3)
where: f4: focal length of the 4th lens.

4 . The imaging optics of claim 1 , wherein the following conditional expression is satisfied
0.01 ≤thiG 1 G 2/ oal≤ 0.03  (4)
where: thiG 1 G 2 : spacing of the 1st lens and the 2nd lens.

5 . The imaging optics of claim 1 , wherein the following conditional expression is satisfied
0.88 ≤allthi/f≤ 2.15  (5)
where: allthi: distance from the object side surface of the 1st lens to the image side surface of the 7th lens.

6 . The imaging optics of claim 1 , wherein the following conditional expression is satisfied
1.95≤ f 567/ f≤ 13.95  (6)
where: f567: combined focal length of the 5th lens, the 6th lens, and the 7th lens.

7 . The imaging optics of claim 1 , wherein the following conditional expression is satisfied
0.20≤ R 7/ f≤ 0.43  (7)
where: R7: paraxial radius of curvature of the image side surface of the 7th lens.

8 . The imaging optics of claim 1 , wherein 1st lens is a biconcave lens.

9 . The imaging optics of claim 1 , wherein the 2nd lens is a biconvex lens.

10 . The imaging optics of claim 1 , wherein the object side surface of the 5th lens is a concave surface facing the object side.

11 . The imaging optics of claim 1 , wherein the object side surface of the 6th lens is a concave surface facing the object side.

12 . The imaging optics of claim 1 , wherein the 7th lens has a negative refractive power.

13 . The imaging optics of claim 1 , wherein the image side surface of the 7th lens is a concave surface facing the image side, and has inflection points in addition to one on the optical axis.

14 . The imaging optics of claim 1 , wherein an aperture stop is disposed between the 2nd lens and the 3rd lens.

15 . An imaging device comprising the imaging optics of claim 1 and an imaging element disposed at the imaging position of the imaging optics.

Assignees

• Tamron Kk

Inventors

• Hayashi Toshihide
• Yokota Koichiro
• Noda Takayuki

Classifications

• G02B13/0045 Primary

  having five or more lenses · CPC title

• G02B13/0015 Primary

  characterised by the lens design · CPC title

• G02B9/64

  having more than six components · CPC title