# US 10,310,221 B2 · Optical lens assembly, image capturing apparatus and electronic device

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 10,310,221 B2
- Document ID: US10310221B2
- Status: Granted
- Kind: B2
- Application number: 15/689,236
- Filed: 2017-08-29
- Published: 2018-01-04
- Granted: 2019-06-04
- Earliest claimed: 2016-04-06
- Assignees: Largan Precision Co., Ltd.
- Applicants: Largan Precision Co., Ltd.
- Inventors: Lin-Yao Liao; Hsin-Hsuan Huang; Shu-Yun Yang
- Web page: https://patentgrep.com/patent/US10310221B2

## CPC

- G02B 13/004: {having four lenses}
- G02B 9/34: having four components only
- G02B 13/04: Reversed telephoto objectives
- G02B 27/0025: {for optical correction, e.g. distorsion, aberration}
- G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS

## Abstract

This invention provides an optical lens assembly including, in order from an object side to an image side: a first lens element with negative refractive power having an image-side surface being concave in a paraxial region thereof; a second lens element having positive refractive power; a third lens element having an object-side surface being concave in a paraxial region thereof; and a fourth lens element having an object-side surface being convex in a paraxial region thereof and an image-side surface being concave in a paraxial region thereof, the image-side surface thereof having at least one convex shape in an off-axis region thereof; wherein the optical lens assembly has a total of four lens elements. With such configuration, the optical lens assembly is characterized by a reduced size and a wide field of view.

## Claims

### Claim 1

An optical lens assembly, comprising, in order from an object side to an image side:
a first lens element with negative refractive power and having an object-side surface being concave in a paraxial region thereof;
a second lens element with positive refractive power;
a third lens element with positive refractive power; and
a fourth lens element with negative refractive power having an object-side surface being convex in a paraxial region thereof and an image-side surface being concave in a paraxial region thereof, the image-side surface thereof having at least one convex shape in an off-axis region thereof;
wherein an axial distance between the first lens element and the second lens element is T12, an axial distance between the second lens element and the third lens element is T23, a focal length of the optical lens assembly is f, a curvature radius of the image-side surface of the fourth lens element is R8, and the following conditions are satisfied:
T23/T12<1.50; and
0<R8/f<1.20;
wherein half of a maximum field of view of the optical lens assembly is HFOV, and the following condition is satisfied:
1.25<tan(HFOV)<13.0.

### Claim 2 (depends on 1)

The optical lens assembly of claim 1, wherein the third lens element has an object-side surface being concave in a paraxial region thereof and an image-side surface being convex in a paraxial region thereof.

### Claim 3 (depends on 2)

The optical lens assembly of claim 2, wherein a focal length of the first lens element is f1, a focal length of the second lens element is f2, and the following condition is satisfied:
1.0<|f1/f2|<4.0.

### Claim 4 (depends on 2)

The optical lens assembly of claim 2, wherein the axial distance between the first lens element and the second lens element is the greatest among respective axial distances between every two adjacent lens elements of the optical lens assembly.

### Claim 5 (depends on 1)

The optical lens assembly of claim 1, wherein the second lens element has an image-side surface being convex in a paraxial region thereof.

### Claim 6 (depends on 1)

The optical lens assembly of claim 1, wherein the first through fourth lens element are made of plastic, the axial distance between the first lens element and the second lens element is T12, the axial distance between the second lens element and the third lens element is T23, and the following condition is satisfied:
T23/T12<1.0.

### Claim 7 (depends on 1)

The optical lens assembly of claim 1, wherein the axial distance between the first lens element and the second lens element is T12, a central thickness of the second lens element is CT2, and the following condition is satisfied:
0.60<T12/CT2<1.85.

### Claim 8 (depends on 1)

The optical lens assembly of claim 1, wherein a maximum axial distance among the axial distances between respective two adjacent lens elements of the optical lens assembly is ATmax, a minimum axial distance among the axial distances between respective two adjacent lens elements of the optical lens assembly is ATmin, and the following condition is satisfied:
1.0<ATmax/ATmin≤10.28.

### Claim 9 (depends on 1)

The optical lens assembly of claim 1, wherein the focal length of the optical lens assembly is f, the axial distance between the first lens element and the second lens element is T12, and the following condition is satisfied:
0<f/T12<2.0.

### Claim 10 (depends on 1)

The optical lens assembly of claim 1, wherein the object-side surface of the first lens element has at least one convex shape in an off-axis region thereof.

### Claim 11 (depends on 1)

The optical lens assembly of claim 1, further comprising an aperture stop disposed between the first lens element and the second lens element.

### Claim 12 (depends on 1)

An image capturing apparatus comprising the optical lens assembly of claim 1 and an image sensor.

### Claim 13 (depends on 12)

An electronic device comprising the image capturing apparatus of claim 12.

### Claim 14

An optical lens assembly, comprising, in order from an object side to an image side:
a first lens element with negative refractive power and having an object-side surface being concave in a paraxial region thereof;
a second lens element with positive refractive power;
a third lens element with positive refractive power; and
a fourth lens element with either positive refractive power or negative refractive power and having an object-side surface being convex in a paraxial region thereof and an image-side surface being concave in a paraxial region thereof, the image-side surface thereof having at least one convex shape in an off-axis region thereof;
wherein a focal length of the first lens element is f1, a focal length of the second lens element is f2, a focal length of the optical lens assembly is f, a curvature radius of the image-side surface of the fourth lens element is R8, and the following conditions are satisfied:
1.0<|f1/f2|<4.0; and
0<R8/f<4.0;
wherein half of a maximum field of view of the optical lens assembly is HFOV, and the following condition is satisfied:
1.25<tan(HFOV)<13.0.

### Claim 15 (depends on 14)

The optical lens assembly of claim 14, wherein the fourth lens element has negative refractive power, and both of an object-side surface and an image-side surface of each of the first through fourth lens element are aspheric.

### Claim 16 (depends on 14)

The optical lens assembly of claim 14, wherein the second lens element has an image-side surface being convex in a paraxial region thereof.

### Claim 17 (depends on 14)

The optical lens assembly of claim 14, wherein the third lens element has an object-side surface being concave in a paraxial region thereof and an image-side surface being convex in a paraxial region.

### Claim 18 (depends on 14)

The optical lens assembly of claim 14, wherein every two adjacent lens elements among the first through fourth lens elements are not cemented.

### Claim 19 (depends on 14)

The optical lens assembly of claim 14, wherein the focal length of the first lens element is f1, the focal length of the second lens element is f2, and the following condition is satisfied:
1.6<|f1/f2|<3.5.

### Claim 20 (depends on 14)

The optical lens assembly of claim 14, further comprising an aperture stop disposed between the first lens element and the second lens element.

### Claim 21 (depends on 14)

The optical lens assembly of claim 14, wherein an axial distance between the first lens element and the second lens element is the greatest among respective axial distances between every two adjacent lens elements of the optical lens assembly.

### Claim 22 (depends on 14)

An image capturing apparatus comprising the optical lens assembly of claim 14 and an image sensor.

### Claim 23 (depends on 22)

An electronic device comprising the image capturing apparatus of claim 22.

### Claim 24

An optical lens assembly, comprising, in order from an object side to an image side:
a first lens element with negative refractive power and having an object-side surface being concave in a paraxial region thereof;
a second lens element with positive refractive power and having an image-side surface being convex in a paraxial region thereof;
a third lens element with positive refractive power;
a fourth lens element with either positive refractive power or negative refractive power and having an object-side surface being convex in a paraxial region thereof and an image-side surface being concave in a paraxial region thereof, the image-side surface thereof having at least one convex shape in an off-axis region thereof; and
an aperture stop disposed between the first lens element and the second lens element;
wherein half of a maximum field of view of the optical lens assembly is HFOV, and the following condition is satisfied:
1.25<tan(HFOV)<13.0.

### Claim 25 (depends on 24)

The optical lens assembly of claim 24, wherein the third lens element has an object-side surface being concave in a paraxial region thereof and an image-side surface being convex in a paraxial region thereof.

### Claim 26 (depends on 24)

The optical lens assembly of claim 24, wherein half of the maximum field of view of the optical lens assembly is HFOV, and the following condition is satisfied:
1.73≤tan(HFOV)<13.0.