Optical imaging lens assembly

1. An optical imaging lens assembly comprising, sequentially along an optical axis from an object side to an image side, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens,

wherein the first lens has a positive refractive power;

each of the second lens, the third lens, and the sixth lens has a negative refractive power;

at least one of the fourth lens or the fifth lens has a positive refractive power;

an object-side surface of the first lens and an image-side surface of the fourth lens are convex surfaces; and

an image-side surface of the second lens and an image-side surface of the sixth lens are concave surfaces;

wherein a total effective focal length f of the optical imaging lens assembly and a radius of curvature R 9 of an object-side surface of the fifth lens satisfy: f/|R 9 |≤0.35, and

wherein the total effective focal length f of the optical imaging lens assembly and an entrance pupil diameter EPD of the optical imaging lens assembly satisfy: f/EPD≤1.8.

2. The optical imaging lens assembly according to claim 1 , wherein an effective focal length f 1 of the first lens and an effective focal length f 2 of the second lens satisfy: −1<f 1 /f 2 <0.

3. An optical imaging lens assembly comprising, sequentially along an optical axis from an object side to an image side, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens,

wherein the first lens has a positive refractive power, and an object-side surface of the first lens is a convex surface;

the second lens has a negative refractive power, and an image-side surface of the second lens is a concave surface;

the third lens has a positive refractive power or a negative refractive power;

the fourth lens has a positive refractive power, and an image-side surface of the fourth lens is a convex surface;

the fifth lens has a positive refractive power or a negative refractive power, an object-side surface of the fifth lens is a concave surface, and an image-side surface of the fifth lens is a convex surface; and

the sixth lens has a negative refractive power, and an image-side surface of the sixth lens is a concave surface;

wherein a total effective focal length f of the optical imaging lens assembly and a radius of curvature R 10 of the image-side surface of the fifth lens satisfy: f/|R 10 |≤0.5, and

wherein the total effective focal length f of the optical imaging lens assembly and an entrance pupil diameter EPD of the optical imaging lens assembly satisfy: f/EPD≤1.8.

4. The optical imaging lens assembly according to claim 1 , wherein the total effective focal length f of the optical imaging lens assembly and an effective focal length f 1 of the first lens satisfy: 1<f/f 1 <1.5.

5. The optical imaging lens assembly according to claim 1 , wherein a center thickness CT 1 of the first lens on the optical axis and a center thickness CT 2 of the second lens on the optical axis satisfy: 2.0<CT 1 /CT 2 <3.5.

6. The optical imaging lens assembly according to claim 1 , wherein the total effective focal length f of the optical imaging lens assembly and a radius of curvature R 12 of the image-side surface of the sixth lens satisfy: 2.5<f/R 12 <4.0.

7. The optical imaging lens assembly according to claim 1 , wherein the total effective focal length f of the optical imaging lens assembly and a radius of curvature R 1 of the object-side surface of the first lens satisfy: 2≤f/R 1 <2.5.

8. The optical imaging lens assembly according to claim 1 , wherein the fourth lens has a positive refractive power, and an effective focal length f 4 of the fourth lens and the total effective focal length f of the optical imaging lens assembly satisfy: 0.7<f 4 /f<1.2.

9. The optical imaging lens assembly according to claim 1 , wherein an abbe number V 1 of the first lens and an abbe number V 2 of the second lens satisfy: 2.0<V 1 /V 2 <4.0.

10. The optical imaging lens assembly according to claim 1 , wherein an incident angle β 62 of an upper ray of a maximal field of view entering on the image-side surface of the sixth lens satisfies: 7°<β 62 <12°.

11. The optical imaging lens assembly according to claim 3 , wherein the total effective focal length f of the optical imaging lens assembly and an effective focal length f 1 of the first lens satisfy: 1<f/f 1 <1.5.

12. The optical imaging lens assembly according to claim 11 , wherein the effective focal length f 1 of the first lens and an effective focal length f 2 of the second lens satisfy: −1<f 1 /f 2 <0.

13. The optical imaging lens assembly according to claim 12 , wherein an abbe number V 1 of the first lens and an abbe number V 2 of the second lens satisfy: 2.0<V 1 /V 2 <4.0.

14. The optical imaging lens assembly according to claim 13 , wherein a center thickness CT 1 of the first lens on the optical axis and a center thickness CT 2 of the second lens on the optical axis satisfy: 2.0<CT 1 /CT 2 <3.5.

15. The optical imaging lens assembly according to claim 3 , wherein an effective focal length f 4 of the fourth lens and the total effective focal length f of the optical imaging lens assembly satisfy: 0.7<f 4 /f<1.2.

16. The optical imaging lens assembly according to claim 3 , wherein the total effective focal length f of the optical imaging lens assembly and a radius of curvature R 1 of the object-side surface of the first lens satisfy: 2≤f/R 1 <2.5.

17. The optical imaging lens assembly according to claim 3 , wherein the total effective focal length f of the optical imaging lens assembly and a radius of curvature R 12 of the image-side surface of the sixth lens satisfy: 2.5<f/R 12 <4.0.

18. The optical imaging lens assembly according to claim 17 , wherein an incident angle β 62 of an upper ray of a maximal field of view entering on the image-side surface of the sixth lens satisfies: 7°<β 62 <12°.