US-12625341-B2 - Light blocking sheet, imaging lens assembly and electronic device

US12625341B2US 12625341 B2US12625341 B2US 12625341B2US-12625341-B2

Abstract

A light blocking sheet includes a central opening and a plurality of light blocking structures. A central axis passes through the central opening. The light blocking structures surround an inner peripheral surface of the central opening, the light blocking structures are tapered and extended from the central opening towards a direction close to the central axis, and the light blocking structures are for defining a circumscribed circle and an inscribed circle, wherein a plurality of inscribed circle ends of the light blocking structures close to the central axis are contacted with the inscribed circle, and a plurality of circumscribed circle ends of the light blocking structures away from the central axis are contacted with the circumscribed circle.

Inventors

Shu-Yun Yang
Chen-Wei Fan
Ming-Ta Chou

Assignees

LARGAN PRECISION CO., LTD.

Dates

Publication Date: 20260512
Application Date: 20220517
Priority Date: 20210628

Claims (18)

1 . A light blocking sheet, comprising: a central opening, a central axis passing through the central opening; and a plurality of light blocking structures surrounding an inner peripheral surface of the central opening, the light blocking structures tapered and extended from the central opening towards a direction close to the central axis, and the light blocking structures for defining a circumscribed circle and an inscribed circle, wherein a plurality of inscribed circle ends of the light blocking structures close to the central axis are contacted with the inscribed circle, and a plurality of circumscribed circle ends of the light blocking structures away from the central axis are contacted with the circumscribed circle; wherein, a light transmission portion is between the inscribed circle and each of the light blocking structures, and a light blocking portion is between the circumscribed circle and each of the light blocking structures; wherein, a radius of the inscribed circle is Ri, a radius of the circumscribed circle is Ro, a distance between two of the inscribed circle ends adjacent to each other is L, a value of an area of the circumscribed circle minus an area of the inscribed circle is AA, an area of the light transmission portions is A1, an area of the light blocking portions is A2, and the following conditions are satisfied: 0.27≤( Ro−Ri )/ L≤ 1.32; 34 μm≤ Ro−Ri≤ 157 μm; AA=A 1+ A 2; and 1.05≤ A 1/ A 2≤3.4.
2 . The light blocking sheet of claim 1 , wherein the light blocking sheet and the light blocking structures are formed integrally.
3 . The light blocking sheet of claim 2 , wherein a surface of the light blocking sheet comprises a matting layer.
4 . The light blocking sheet of claim 2 , wherein the radius of the inscribed circle is Ri, the radius of the circumscribed circle is Ro, and the following condition is satisfied: 46 μm≤ Ro−Ri≤ 112 μm.
5 . The light blocking sheet of claim 2 , wherein a number of the light blocking structures is N, and the following condition is satisfied: 28 ≤N ≤93.
6 . The light blocking sheet of claim 2 , wherein the light transmission portion of each of the light blocking structures comprises at least one arc segment, and a curvature center of the at least one arc segment is disposed in the inscribed circle.
7 . An imaging lens assembly, comprising: the light blocking sheet of claim 1 ; and at least two optical lens elements, the at least two optical lens elements and the light blocking sheet disposed in a lens barrel along the central axis; wherein, the imaging lens assembly has a first field of view, the first field of view is FOV1, and the following condition is satisfied: 18 degrees≤FOV1≤51 degrees.
8 . An electronic device, comprising: at least two imaging lens assemblies, the at least two imaging lens assemblies having different field of views, one of the at least two imaging lens assemblies being a first imaging lens assembly, and the first imaging lens assembly having a first field of view, wherein the first imaging lens assembly comprises at least one light blocking sheet, and the at least one light blocking sheet comprises: a central opening, a central axis of the first imaging lens assembly passing through the central opening; and a plurality of light blocking structures surrounding an inner peripheral surface of the central opening, the light blocking structures tapered and extended from the central opening towards a direction close to the central axis, and the light blocking structures for defining a circumscribed circle and an inscribed circle, wherein a plurality of inscribed circle ends of the light blocking structures close to the central axis are contacted with the inscribed circle, and a plurality of circumscribed circle ends of the light blocking structures away from the central axis are contacted with the circumscribed circle; wherein a light transmission portion is between the inscribed circle and each of the light blocking structures, and a light blocking portion is between the circumscribed circle and each of the light blocking structures; wherein, the first field of view is FOV1, a radius of the inscribed circle is Ri, a radius of the circumscribed circle is Ro, a distance between two of the inscribed circle ends adjacent to each other is L, a value of an area of the circumscribed circle minus an area of the inscribed circle is AA, an area of the light transmission portions is A1, an area of the light blocking portions is A2, and the following conditions are satisfied: 0.27≤( Ro−Ri )/ L≤ 1.32; 18 degrees≤FOV1≤51 degrees; 34 μm≤ Ro−Ri≤ 157 μm; AA=A 1+ A 2; and 1.05≤ A 1/ A 2≤3.4.
9 . The electronic device of claim 8 , wherein another one of the at least two imaging lens assemblies is a second imaging lens assembly, and the second imaging lens assembly has a second field of view, the second field of view is FOV2, and the following condition is satisfied: 68 degrees≤FOV2≤175 degrees.
10 . The electronic device of claim 9 , wherein a number of the at least two imaging lens assemblies is at least three, another one of the at least three imaging lens assemblies is a third imaging lens assembly, and the third imaging lens assembly has a third field of view, the third field of view is FOV3, and the following condition is satisfied: 5 degrees≤FOV3≤22 degrees.
11 . The electronic device of claim 8 , wherein the first imaging lens assembly further comprises: at least two optical lens elements, one of the at least two optical lens elements has a maximum outer diameter; wherein, a number of the at least one light blocking sheet is plural, and the central opening of one of the light blocking sheets has a minimum inner diameter; wherein, the maximum outer diameter of the one of the at least two optical lens elements is φMax, the minimum inner diameter of the central opening of the one of the light blocking sheets is φmin, and the following condition is satisfied: 0.29≤φmin/φMax≤0.79.
12 . The electronic device of claim 8 , wherein the first imaging lens assembly further comprises: at least two optical lens elements, one of the at least two optical lens elements has a maximum outer diameter; wherein, the maximum outer diameter of the one of the at least two optical lens elements is φMax, an effective focal length of the first imaging lens assembly is EFL, and the following condition is satisfied: 0.8 ≤EFL /φMax≤4.2.
13 . The electronic device of claim 8 , wherein the first field of view is FOV1, and the following condition is satisfied: 22 degrees≤FOV1≤40 degrees.
14 . The electronic device of claim 8 , wherein the at least one light blocking sheet and the light blocking structures are formed integrally.
15 . The electronic device of claim 14 , wherein a surface of the at least one light blocking sheet comprises a matting layer.
16 . The electronic device of claim 14 , wherein the radius of the inscribed circle is Ri, the radius of the circumscribed circle is Ro, and the following condition is satisfied: 46 μm≤ Ro−Ri ≤112 μm.
17 . The electronic device of claim 14 , wherein a number of the light blocking structures is N, and the following condition is satisfied: 28 ≤N ≤93.
18 . The electronic device of claim 14 , wherein the light transmission portion of each of the light blocking structures comprises at least one arc segment, and a curvature center of the at least one arc segment is disposed in the inscribed circle.

Description

RELATED APPLICATIONS This application claims priority to Taiwan Application Serial Number 110123641, filed Jun. 28, 2021, which is herein incorporated by reference. BACKGROUND Technical Field The present disclosure relates to a light blocking sheet and an imaging lens assembly. More particularly, the present disclosure relates to a light blocking sheet and an imaging lens assembly applicable to the portable electronic devices. Description of Related Art In recent years, portable electronic devices have developed rapidly. For example, intelligent electronic devices and tablets, etc., have been filled in the lives of modern people, and the imaging lens assemblies and the light blocking sheets thereof employed in the portable electronic devices have also prospered. However, as technology advances, the quality requirements of the light blocking sheet are becoming higher and higher. In detail, a plurality of light blocking structures of the light blocking sheet can reduce the noise interference when the imaging lens assembly is in the scene of the accent light source. When the extended heights of the light blocking structures are increased, the anti-noise ability of the imaging lens assembly in the scene of the accent light source can be enhanced. However, at the same time, the image quality will decrease easily due to the excessive shading of the imaging lens assembly. Therefore, a light blocking sheet which can reduce the excessive shading and have the anti-noise ability in the scene of the accent light source needs to be developed. SUMMARY According to one aspect of the present disclosure, a light blocking sheet includes a central opening and a plurality of light blocking structures. A central axis passes through the central opening. The light blocking structures surround an inner peripheral surface of the central opening, the light blocking structures are tapered and extended from the central opening towards a direction close to the central axis, and the light blocking structures are for defining a circumscribed circle and an inscribed circle, wherein a plurality of inscribed circle ends of the light blocking structures close to the central axis are contacted with the inscribed circle, and a plurality of circumscribed circle ends of the light blocking structures away from the central axis are contacted with the circumscribed circle. A light transmission portion is between the inscribed circle and each of the light blocking structures, and a light blocking portion is between the circumscribed circle and each of the light blocking structures. When a radius of the inscribed circle is Ri, a radius of the circumscribed circle is Ro, a value of an area of the circumscribed circle minus an area of the inscribed circle is AA, an area of the light transmission portions is A1, and an area of the light blocking portions is A2, the following conditions are satisfied: 34 μm≤Ro−Ri≤157 μm; AA=A1+A2; and 0.9≤A1/A2≤5.4. According to one aspect of the present disclosure, an imaging lens assembly includes the light blocking sheet of the aforementioned aspect and at least two optical lens elements. The at least two optical lens elements and the light blocking sheet are disposed in a lens barrel along the central axis. The imaging lens assembly has a first field of view, when the first field of view is FOV1, the following condition is satisfied: 18 degrees≤FOV1≤51 degrees. According to one aspect of the present disclosure, an electronic device includes at least two imaging lens assemblies. The at least two imaging lens assemblies have different field of views, one of the at least two imaging lens assemblies is a first imaging lens assembly, and the first imaging lens assembly has a first field of view, wherein the first imaging lens assembly includes at least one light blocking sheet, and the at least one light blocking sheet includes a central opening and a plurality of light blocking structures. A central axis of the first imaging lens assembly passes through the central opening. The light blocking structures surround an inner peripheral surface of the central opening, the light blocking structures are tapered and extended from the central opening towards a direction close to the central axis, and the light blocking structures are for defining a circumscribed circle and an inscribed circle, wherein a plurality of inscribed circle ends of the light blocking structures close to the central axis are contacted with the inscribed circle, and a plurality of circumscribed circle ends of the light blocking structures away from the central axis are contacted with the circumscribed circle. When the first field of view is FOV1, a radius of the inscribed circle is Ri, and a radius of the circumscribed circle is Ro, the following conditions are satisfied: 18 degrees≤FOV1≤51 degrees; and 34 μm≤Ro−Ri≤157 μm. BRIEF DESCRIPTION OF THE DRAWINGS The present disclosure can be more fully understood by reading the following detailed description of