Optical image capturing system

Patent metadata

Field	Value
Publication number	US-9547154-B2
Application number	US-201514861122-A
Country	US
Kind code	B2
Filing date	Sep 22, 2015
Priority date	Jun 4, 2015
Publication date	Jan 17, 2017
Grant date	Jan 17, 2017

Abstract

An optical image capturing system, sequentially including a first lens element, a second lens element, a third lens element and a fourth lens element from an object side to an image side, is provided. The first lens element has positive refractive power. The second through third lens elements have refractive power. The fourth lens element has negative refractive power. At least one of the image side surface and the object side surface of each of the four lens elements are aspheric. The optical lens elements can increase aperture value and improve the imagining quality for use in compact cameras.

First claim

What is claimed is:

1. An optical image capturing system, from an object side to an image side, comprising:
a first lens element with refractive power;
a second lens element with refractive power;
a third lens element with refractive power;
a fourth lens element with refractive power; and
an image plane;
wherein the optical image capturing system consists of four lens elements with refractive power, at least two lens elements among the first through fourth lens elements respectively have at least one inflection point on at least one surface thereof, at least one of the first through fourth lens elements has positive refractive power, an object-side surface and an image-side surface of the fourth lens element are aspheric, focal lengths of the first through fourth lens elements are f1, 12, f3 and f4 respectively, a focal length of the optical image capturing system is f, an entrance pupil diameter of the optical image capturing system is HEP, a distance from an axial point on an object-side surface of the first lens element to an axial point on the image plane is HOS, thicknesses in parallel with an optical axis of the first lens element, the second lens element, the third lens element and the fourth lens element at height ½ HEP respectively are ETP1, ETP2, ETP3 and ETP4, a sum of ETP1 to ETP4 described above is SETP, thicknesses of the first lens element, the second lens element, the third lens element and the fourth lens element on the optical axis respectively are TP1, TP2, TP3 and TP4, a sum of TP1 to TP4 described above is STP, and the following relations are satisfied: 1.2≦f/HEP≦6.0, 0.5≦HOS/f≦3 and 0.5≦SETP/STP<1.

2. The optical image capturing system of claim 1 , wherein a horizontal distance in parallel with the optical axis from a coordinate point on the object-side surface of the first lens element at height ½ HEP to the image plane is ETL, a horizontal distance in parallel with the optical axis from a coordinate point on the object-side surface of the first lens element at height ½ HEP to a coordinate point on the image-side surface of the fourth lens element at height ½ HEP is EIN, and the following relation is satisfied: 0.2≦EIN/ETL<1.

3. The optical image capturing system of claim 1 , wherein the thickness in parallel with the optical axis of the first lens element at height ½ HEP is ETP1, the thickness in parallel with the optical axis of the second lens element at height ½ HEP is ETP2, the thickness in parallel with the optical axis of the third lens element at height ½ HEP is ETP3, the thickness in parallel with the optical axis of the fourth lens element at height ½ HEP is ETP4, the sum of ETP1 to ETP4 described above is SETP, and the following relation is satisfied: 0.3≦SETP/EIN≦0.8.

4. The optical image capturing system of claim 1 , wherein the optical image capturing system comprises a light filtration element, the light filtration element is located between the fourth lens element and the image plane, a distance in parallel with the optical axis from a coordinate point on the image-side surface of the fourth lens element at height ½ HEP to the light filtration element is EIR, a distance in parallel with the optical axis from an axial point on the image-side surface of the fourth lens element to the light filtration element is PIR, and the following relation is satisfied: 0.2≦EIR/PIR≦0.8.

5. The optical image capturing system of claim 1 , wherein at least one of the four lens elements has at least two inflection points on at least one surface.

6. The optical image capturing system of claim 1 , wherein the optical image capturing system has a maximum height of image capturing HOI perpendicular to the optical axis on the image plane, contrast transfer rates of modulation transfer with half frequencies (MTF values) at the optical axis on the image plane, 0.3 HOI and 0.7 HOI are respectively denoted by MTFH0, MTFH3 and MTFH7, and the following relations are satisfied: MTFH0≧0.3, MTFH3≧0.2 and MTFH7≧0.1.

7. The optical image capturing system of claim 1 , wherein a half of maximum view angle of the optical image capturing system is HAF, and the following relation is satisfied: 0.4≦| tan(HAF)|≦3.0.

8. The optical image capturing system of claim 1 , wherein a horizontal distance in parallel with the optical axis from a coordinate point on the image-side surface of the fourth lens element at height ½ HEP to the image plane is EBL, a horizontal distance in parallel with the optical axis from an axial point on the image-side surface of the fourth lens element to the image plane is BL, and the following relation is satisfied: 0.5≦EBL/BL<1.

9. The optical image capturing system of claim 1 , further comprising an aperture stop, a distance from the aperture stop to the image plane on the optical axis is InS, an image sensing device is disposed on the image plane, a height for image formation on the image plane perpendicular to the optical axis in the optical image capturing system is HOI, and the following relations are satisfied: 0.2≦InS/HOS≦1.1 and 0.5≦HOS/HOI≦1.6.

10. An optical image capturing system, from an object side to an image side, comprising:
a first lens element with positive refractive power;
a second lens element with refractive power;
a third lens element with refractive power;
a fourth lens element with negative refractive power; and
an image plane;
wherein the optical image capturing system consists of four lens elements with refractive power, at least two lens elements among the four lens elements respectively have at least one inflection point on at least one surface thereof, an object-side surface and an image-side surface of the fourth lens element are aspheric, focal lengths of the first through fourth lens elements are f1, f2, f3 and f4 respectively, a focal length of the optical image capturing system is f, an entrance pupil diameter of the optical image capturing system is HEP, a distance from an axial point on an object-side surface of the first lens element to an axial point on the image plane is HOS, a half of maximum view angle of the optical image capturing system is HAF, a horizontal distance in parallel with the optical axis from a coordinate point on the object-side surface of the first lens element at height ½ HEP to the image plane is ETL, a horizontal distance in parallel with the optical axis from a coordinate point on the object-side surface of the first lens element at height ½ HEP to a coordinate point on the image-side surface of the fourth lens element at height ½ HEP is EIN, and the following relations are satisfied: 1.2≦f/HEP≦6.0, 0.5≦HOS/f≦3.0, 0.4≦| tan(HAF)|3.0 and 0.2≦EIN/ETL<1.

11. The optical image capturing system of claim 10 , wherein a horizontal distance in parallel with the optical axis from a coordinate point on the image-side surface of the third lens element at height ½ HEP to a coordinate point on the object-side surface of the fourth lens element at height ½ HEP is ED34, a distance from the third lens element to the fourth lens element on the optical axis is IN34, and the following relation is satisfied: 1<ED34/IN34≦50.

12. The optical image capturing system of claim 10 , wherein a horizontal distance in parallel with the optical axis from a coordinate point on the image-side surface of the second lens element at height ½ HEP to a coordinate point on the object-side surface of the third lens element at height ½ HEP is ED23, a distance from the second lens element to the third lens element on the optical axis is IN23, and the following relation is satisfied: 0.1≦ED23/IN23<1.

13. The optical image capturing system of claim 10 , wherein a horizontal distance in parallel with the optical axis from a c

Assignees

• Ability Opto Electronics Technology Co Ltd

Inventors

• Liu yao-wei
• Chang Yeong-Ming

Classifications

• G02B9/34

  having four components only · CPC title

• G02B13/004 Primary

  having four lenses · CPC title