Imaging lens system, camera module and electronic device

1. An imaging lens system, having an optical axis, and the imaging lens system comprising:

at least one plastic lens element, wherein the at least one plastic lens element comprises, in order from a center to a periphery thereof:

an optical effective portion, wherein the optical axis passes through the optical effective portion; and

an outer ring portion, wherein the outer ring portion surrounds the optical effective portion, and the outer ring portion comprises, on at least one of an object side and an image side thereof:

at least one annular groove structure, wherein the at least one annular groove structure is in a full-circle form, and the at least one annular groove structure is tapered off from the object side to the image side of the outer ring portion or from the image side to the object side of the outer ring portion;

at least one conical surface, located closer to the optical effective portion than the at least one annular groove structure;

at least one flat abutting portion, wherein the at least one flat abutting portion is located closer to the optical effective portion than the at least one annular groove structure, and the at least one flat abutting portion is in physical contact with an optical element which is adjacent to the at least one plastic lens element of the imaging lens system; and

at least one full-circle connecting portion, wherein the at least one full-circle connecting portion is connected to the at least one annular groove structure, the at least one full-circle connecting portion is located farther away from the optical effective portion than the at least one annular groove structure, the at least one full-circle connecting portion defines a depth of the at least one annular groove structure, and the at least one full-circle connecting portion is exposed to air and is not in physical contact with the optical element and another optical element adjacent thereto;

wherein the at least one annular groove structure has an annular bottom end surface extending in a direction substantially perpendicular to the optical axis;

and

wherein a first distance in parallel with the optical axis between the at least one full-circle connecting portion and the annular bottom end surface is d, and the following condition is satisfied:

0.005 [mm]≤ d <0.2 [mm].

2. The imaging lens system of claim 1 , wherein the first distance in parallel with the optical axis between the at least one full-circle connecting portion and the annular bottom end surface is d, and the following condition is satisfied:

0.01 [mm]≤ d <0.13 [mm].

3. The imaging lens system of claim 1 , wherein the at least one plastic lens element is correspondingly assembled with the optical element by the at least one conical surface to be aligned with the optical axis.

4. The imaging lens system of claim 1 , wherein a second distance in parallel with the optical axis between the at least one flat abutting portion and the annular bottom end surface is D, and the following condition is satisfied:

0.05 [mm]< D <0.4 [mm].

5. The imaging lens system of claim 2 , wherein the first distance in parallel with the optical axis between the at least one full-circle connecting portion and the annular bottom end surface is d, a second distance in parallel with the optical axis between the at least one flat abutting portion and the annular bottom end surface is D, and the following condition is satisfied:

0.02 <d/D <1.0.

6. The imaging lens system of claim 1 , further comprising at least one optical shutter plate, wherein the at least one optical shutter plate is disposed between the at least one plastic lens element and another plastic lens element adjacent to an image side of the at least one optical shutter plate, and the at least one optical shutter plate has an opening being coaxial with the optical axis.

7. The imaging lens system of claim 6 , wherein the at least one plastic lens element adjacent to an object side of the at least one optical shutter plate has a first conical surface, the another plastic lens element adjacent to the image side of the at least one optical shutter plate has a second conical surface, the first conical surface and the second conical surface are correspondingly assembled with each other and form an accommodation space between the at least one plastic lens element and the another plastic lens element, and the at least one optical shutter plate is disposed in the accommodation space.

8. The imaging lens system of claim 7 , wherein a maximum outer diameter of the at least one optical shutter plate is ΦS, a minimum diameter of the first conical surface is ΦC′, and the following condition is satisfied:

Φ S≤ΦC′.

9. The imaging lens system of claim 5 , wherein a projection of the second distance on the optical axis has at least one part non-overlapping with a projection of the first distance on the optical axis, a third distance in parallel with the optical axis between the at least one flat abutting portion and the at least one full-circle connecting portion is D-d, and the following condition is satisfied:

0 [mm]< D - d <0.39 [mm].

10. The imaging lens system of claim 1 , wherein the outer ring portion of the at least one plastic lens element has a gate trace, the gate trace is located farther away from the optical effective portion than the at least one annular groove structure, and the gate trace is located farther away from the optical effective portion than the at least one full-circle connecting portion.

11. A camera module, comprising:

the imaging lens system of claim 1 ; and

an image sensor disposed on an image surface of the imaging lens system.

12. An electronic device, comprising:

the camera module of claim 11 .

13. The imaging lens system of claim 1 , wherein:

the at least one plastic lens element is at least one optical element;

the optical effective portion is a central portion; and

the at least one annular groove structure has:

a first annular side wall, wherein the first annular side wall is connected to the annular bottom end surface and the at least one full-circle connecting portion, and the first annular side wall extends in a direction away from the annular bottom end surface; and

a second annular side wall, wherein the second annular side wall is connected to the annular bottom end surface, the second annular side wall is located closer to the central portion than the annular bottom end surface, and the second annular side wall extends in a direction away from the annular bottom end surface;

wherein a minimum diameter of the first annular side wall is ϕA1, a maximum diameter of the second annular side wall is ϕA2, a length of the annular bottom end surface in a direction perpendicular to the optical axis is (ϕA1−ϕA2)/2, and the following condition is satisfied:

0.005 [mm]≤(ϕ A 1 −ϕA 2)/2<0.2 [mm].

14. The imaging lens system of claim 13 , wherein the minimum diameter of the first annular side wall is ΦA1, the maximum diameter of the second annular side wall is ΦA2, the length of the annular bottom end surface in the direction perpendicular to the optical axis is (ΦA1−ΦA2)/2, and the following condition is satisfied:

0.01 [mm]≤(Φ A 1 −ΦA 2)/2<0.17 [mm].

15. The imaging lens system of claim 13 , wherein the at least one optical element is correspondingly assembled with a plastic lens element adjacent thereto by the at least one conical surface to be aligned with the optical axis.

16. The imaging lens system of claim 13 , wherein the central portion further comprises a central opening structure, the central opening structure has a first tapered surface and a second tapered surface that surround the central portion, the first tapered surface faces an object side and is tapered off towards an image side, the second tapered surface faces the image side and is tapered off towards the object side, and the first tapered surface and the second tapered surface are connected to form a central opening.

17. The imaging lens system of claim 13 , further comprising at least one optical shutter plate, wherein the at least one optical shutter plate is disposed between the at least one optical element and a plastic lens element, and the at least one optical shutter plate has an opening being coaxial with the optical axis.

18. The imaging lens system of claim 13 , wherein a maximum outer diameter of the at least one optical element is ΦL, the minimum diameter of the first annular side wall is ΦA1, the maximum diameter of the second annular side wall is ΦA2, a maximum diameter of the at least one conical surface is ΦC, and the following condition is satisfied:

Φ L>ΦA 1 >ΦA 2 ≥ΦC.

19. The imaging lens system of claim 13 , wherein a maximum outer diameter of the at least one optical element is ΦL, the minimum diameter of the first annular side wall is ΦA1, the maximum diameter of the second annular side wall is ΦA2, and the following condition is satisfied:

1<[Φ L/ΦA 1 −ΦA 2)]/π2<50.

20. The imaging lens system of claim 13 , wherein the outer ring portion of the at least one optical element has a gate trace, the gate trace is located farther away from the central portion than the at least one annular groove structure, and the gate trace is located farther away from the central portion than the at least one full-circle connecting portion.

21. The imaging lens system of claim 1 , wherein the at least one annular groove structure has:

at least one annular bottom end surface, extending in a direction substantially perpendicular to the optical axis; and

at least one annular top end surface, extending in a direction substantially perpendicular to the optical axis;

wherein the outer ring portion of the at least one plastic lens element has a gate trace, the gate trace is located farther away from the optical effective portion than the at least one annular groove structure, and the gate trace is located farther away from the optical effective portion than the at least one full-circle connecting portion.

22. The imaging lens system of claim 21 , wherein a number of the at least one annular bottom end surface is Nb, a number of the at least one annular top end surface is Nt, and the following condition is satisfied:

Nb=Nt +1.

23. The imaging lens system of claim 21 , wherein the at least one annular groove structure further has:

a first annular side wall, wherein the first annular side wall is connected to the at least one annular bottom end surface and the at least one full-circle connecting portion, and the first annular side wall extends in a direction away from the at least one annular bottom end surface; and

a second annular side wall, wherein the second annular side wall is connected to the at least one annular bottom end surface, the second annular side wall is located closer to the optical effective portion than the at least one annular bottom end surface, and the second annular side wall extends in a direction away from the at least one annular bottom end surface;

wherein a first distance in parallel with the optical axis between the at least one full-circle connecting portion and the at least one annular bottom end surface is d, a minimum diameter of the first annular side wall is ΦA1, a maximum diameter of the second annular side wall is ΦA2, a length of the at least one annular bottom end surface in a direction perpendicular to the optical axis is (ΦA1−ΦA2)/2, and the following condition is satisfied:

0.2<2 d /(Φ A 1 −ΦA 2)<5.0.

24. The imaging lens system of claim 23 , wherein the first distance in parallel with the optical axis between the at least one full-circle connecting portion and the at least one annular bottom end surface is d, the minimum diameter of the first annular side wall is ΦA1, the maximum diameter of the second annular side wall is ΦA2, the length of the at least one annular bottom end surface in the direction perpendicular to the optical axis is (ΦA1−ΦA2)/2, and the following condition is satisfied:

0.3<2 d /(Φ A 1 −ΦA 2)<3.33.