Crushable lens adapter ring

1 . A crushable lens adapter ring, comprising:

a frame, having:

a first end, wherein an outer wall surface of the first end has a first connecting portion for being connected to a first lens having a first diameter;

a second end, wherein an inner wall surface of the second end has a second connecting portion for being connected to a second lens having a second diameter;

at least one crushable portion; and

at least one force application portion having at least one portion adjacent to at least one portion of the at least one crushable portion and configured to, when subjected to a force and displaced in a direction, force the frame to be broken and torn along an extension direction of the at least one crushable portion.

2 . The crushable lens adapter ring according to claim 1 , wherein the at least one crushable portion extends along an axial direction of the frame.

3 . The crushable lens adapter ring according to claim 1 , wherein the at least one crushable portion extends along a circumferential direction of the frame.

4 . The crushable lens adapter ring according to claim 1 , wherein the at least one crushable portion is shaped as a groove and concavely formed at an outer wall surface or an inner wall surface of the frame.

5 . The crushable lens adapter ring according to claim 1 , wherein the at least one crushable portion includes a plurality of holes.

6 . The crushable lens adapter ring according to claim 1 , wherein an outer diameter of the second end is greater than an outer diameter of the first end so as to form a shoulder portion between the first end and the second end, an outer side of the shoulder portion has an inclined surface, and the inclined surface slopes in a direction from the second end to the first end so that a portion of the shoulder portion that corresponds to an area where two inner wall surfaces of the second end are joined forms the at least one crushable portion.

7 . The crushable lens adapter ring according to claim 1 , wherein a minimal thickness of the at least one crushable portion is 0.1 mm to 0.3 mm.

8 . The crushable lens adapter ring according to claim 1 , wherein the frame further has at least one auxiliary crushable portion adjacent to the at least one crushable portion.

9 . The crushable lens adapter ring according to claim 1 , wherein the at least one force application portion is protrudingly provided on an outer wall surface of the frame.

10 . The crushable lens adapter ring according to claim 1 , wherein the at least one force application portion includes a through opening and an inclined force application surface, and an opening diameter of the through opening on an outer wall surface of the frame is less than an opening diameter of the through opening on an inner wall surface of the frame so as to form the inclined force application surface.

11 . The crushable lens adapter ring according to claim 1 , wherein the at least one force application portion is an internally threaded groove or a threaded hole.

12 . The crushable lens adapter ring according to claim 1 , wherein the frame is made of a metal material or a fiber-reinforced plastic material.

13 . The crushable lens adapter ring according to claim 1 , wherein the at least one force application portion includes at least one sunken area, and the sunken area is adjacent to or in communication with the at least one crushable portion.

14 . The crushable lens adapter ring according to claim 13 , wherein the at least one sunken area is located at at least one of an outer wall surface and an inner wall surface of the frame.