OPTICAL ELEMENT HAVING STRAY LIGHT SUPPRESSION STRUCTURE
An optical element having stray light suppression structure includes a main body which is ring-shaped and defines an axial direction. The main body has an inner peripheral face and an outer peripheral face. The main body is for being arranged inside a lens mount. The main body has a first end and a second end along the axial direction and has plural stray light suppression structures on the inner peripheral face. The stray light suppression structures are spacedly arranged around the axial direction. A surface of each stray light suppression structure is non-coplanar with the inner peripheral face. Each stray light suppression structure has a third end closer to the first end and a fourth end closer to the second end. Each stray light suppression structure has an extension path at least partially nonoverlapping a line defined from the third end to the fourth end.
The present invention relates to m optical element having stray light suppression structure.
Description of the Prior ArtAn optical device such as lens assembly is composed of a plurality of optical elements such as lens, spacer ring, or positioning ring. Because only part of the lens can be used for imaging, stray light is generated when light hits the position which is not optical portion. Stray light may reduce the performance of imaging.
To avoid the stray light, rough surface is usually used to disperse light, as shown in patents TW 1612354, TW 1616697, and TW 1639029. The rough surface is formed around the optical portion or on the inner peripheral face of the spacer ring.
However, the bumps or recesses have even shapes. For example, concentric annular grooves or radial linear grooves are often used. The surface for reflecting has a specific orientation. Sometimes the surface concentrates the stray light instead.
SUMMARY OF THE INVENTIONThe main object of the present invention is to provide an optical element having stray light suppression structure to prevent imaging from being affected by stray light.
To achieve the above and other objects, the optical element having stray light suppression structure of the present invention includes a main body. The main body is ring-shaped and defines an axial direction. The main body has an inner peripheral face and an outer peripheral face. The main body is adapted for being arranged inside a lens mount wherein the outer peripheral face of the main body connects to an inner wall of the lens mount. The main body has a first end and a second end along the axial direction. The main body has a plurality of stray light suppression structures on the inner peripheral face. The stray light suppression structures are spacedly arranged around the axial direction. A surface of each of the stray light suppression structures is non-coplanar with the inner peripheral face. Each of the stray light suppression structures has a third end closer to the first end and a fourth end closer to the second end. Each of the stray light suppression structures has an extension path at least partially nonoverlapping a line defined from the third end to the fourth end.
To achieve the above and other objects, the optical element having stray light suppression structure includes a main body. The main body defines an axial direction. The main body has an optical portion at a center thereof. The main body further has a dispersing portion surrounding the optical portion. The main body has a plurality of stray light suppression structures on the dispersing portion. The stray light suppression structures are spacedly arranged around the axial direction. A surface of each of the stray light suppression structures is non-coplanar with the dispersing portion. Each of the stray light suppression structures has a third end closer to the optical portion and a fourth end remote from the optical portion. Each of the stray light suppression structures has an extension path at least partially nonoverlapping a line defined from the third end to the fourth end.
The present invention will become more obvious from the following description when taken in connection with the accompanying drawings, which show, for purpose of illustrations only, the preferred embodiment(s) in accordance with the present invention.
Please refer to
In the present embodiment, each of the stray light suppression structures 13,13a,13b is S-shaped and is a groove, as shown in
In view of the shape of the groove, in the present embodiment, the groove (the stray light suppression structure 13,13c,13f) has a radial cross-section which is trapezoid narrower at the opening and wider at the bottom, as shown in
As shown in
In the present embodiment, each of the stray light suppression structures 13 is S-shaped groove, and the groove (the stray light suppression structure 13) has a radial cross-section which is trapezoid narrower at the opening and wider at the bottom. However, as mentioned above, each of the stray light suppression structures can be V-shaped, zigzag, or other shape which is not linear, and the radial cross-section of the groove can be arc-shaped, reversed triangle, or other shape.
In use, as shown in
In conclusion, the optical element of the present invention has stray light suppression structures which are not linear so as to provide reflection faces in more orientations. Thereby, the stray light can be dispersed better, and the lens assembly can provide better images.
Claims
1. An optical element having stray light suppression structure, including a main body, the main body being ring-shaped and defining an axial direction, the main body having an inner peripheral face and an outer peripheral face, the main body being adapted for being arranged inside a lens mount wherein the outer peripheral face of the main body connects to an inner wall of the lens mount, the main body having a first end and a second end along the axial direction, the main body having a plurality of stray light suppression structures on the inner peripheral face, the stray light suppression structures being spacedly arranged around the axial direction, a surface of each of the stray light suppression structures being non-coplanar with the inner peripheral face, each of the stray light suppression structures having a third end closer to the first end and a fourth end closer to the second end, each of the stray light suppression structures having an extension path at least partially nonoverlapping a line defined from the third end to the fourth end.
2. The optical element having stray light suppression structure of claim 1, wherein each of the stray light suppression structures is V-shaped.
3. The optical element having stray light suppression structure of claim 1, wherein each of the stray light suppression structures is S-shaped.
4. The optical element having stray light suppression structure of claim 1, wherein each of the stray light suppression structures is zigzag.
5. The optical element having stray light suppression structure of claim 2, wherein each of the stray light suppression structures includes two segments connected together, an angle between the two segments is larger than or smaller than 180 degrees.
6. The optical element having stray light suppression structure of claim 4, wherein each of the stray light suppression structures includes three segments connected sequently, an angle between any two adjacent ones of the segments is larger than or smaller than 180 degrees.
7. The optical element having stray light suppression structure of claim 1, wherein each of the stray light suppression structures is a groove, a bottom of the groove has a radial cross-section which is concave arc-shaped.
8. The optical element having stray light suppression structure of claim 1, wherein each of the stray light suppression structures is a groove, the groove has a radial cross-section which is reversed triangle.
9. The optical element having stray light suppression structure of claim 1, wherein each of the stray light suppression structures is a groove, the groove has a radial cross-section which is trapezoid narrower at an opening and wider at a bottom.
10. An optical element having stray light suppression structure, including a main body, the main body defining an axial direction, the main body having an optical portion at a center thereof, the main body further having a dispersing portion surrounding the optical portion, the main body having a plurality of stray light suppression structures on the dispersing portion, the stray light suppression structures being spacedly arranged around the axial direction, a surface of each of the stray light suppression structures being non-coplanar with the dispersing portion, each of the stray light suppression structures having a third end closer to the optical portion and a fourth end remote from the optical portion, each of the stray light suppression structures having an extension path at least partially nonoverlapping a line defined from the third end to the fourth end.
11. The optical element having stray light suppression structure of claim 10, wherein each of the stray light suppression structures is V-shaped.
12. The optical element having stray light suppression structure of claim 10, wherein each of the stray light suppression structures is S-shaped.
13. The optical element having stray light suppression structure of claim 10, wherein each of the stray light suppression structures is zigzag.
14. The optical element having stray light suppression structure of claim 11, wherein each of the stray light suppression structures includes two segments connected together, an angle between the two segments is larger than or smaller than 180 degrees.
15. The optical element having stray light suppression structure of claim 13, wherein each of the stray light suppression structures includes three segments connected sequently, an angle between any two adjacent ones of the segments is larger than or smaller than 180 degrees.
16. The optical element having stray light suppression structure of claim 10, wherein each of the stray light suppression structures is a groove, a bottom of the groove has a radial cross-section which is concave arc-shaped.
17. The optical element having stray light suppression structure of claim 10, wherein each of the stray light suppression structures is a groove, the groove has a radial cross-section which is reversed triangle.
18. The optical element having stray light suppression structure of claim 10, wherein each of the stray light suppression structures is a groove, the groove has a radial cross-section which is trapezoid narrower at an opening and wider at a bottom.
Type: Application
Filed: Aug 7, 2019
Publication Date: Feb 11, 2021
Inventor: Yung-Fu LIANG (Taichung City)
Application Number: 16/534,707