Optical imaging lens including eight lenses of −+−+−++−, −+−+−−+−, ++−−+−+−, ++−+−++− or −+−−+−+− refractive powers
The disclosure discloses an optical imaging lens. The optical imaging lens sequentially from an object side to an image side along an optical axis includes, a first lens with refractive power, a second lens with positive refractive power, a third lens with negative refractive power, a fourth lens with refractive power, a fifth lens with refractive power, a sixth lens with refractive power, a seventh lens with positive refractive power and an eighth lens with negative refractive power. A total effective focal length f of the optical imaging lens and the maximum Field of View (FOV) of the optical imaging lens meet f×TAN(FOV/2)>4.0 mm; and the total effective focal length f of the optical imaging lens, a center thickness CT 7 of the seventh lens on the optical axis and a CT 8 of the eighth lens on the optical axis meet f/(CT 7 +CT 8 )≥5.0.
1. An optical imaging lens, sequentially comprising from an object side to an image side along an optical axis:
a first lens with refractive power;
a second lens with positive refractive power;
a third lens with negative refractive power;
a fourth lens with refractive power;
a fifth lens with refractive power;
a sixth lens with refractive power;
a seventh lens with positive refractive power; and
an eighth lens with negative refractive power;
wherein, a total effective focal length f of the optical imaging lens and a maximum Field of View (FOV) of the optical imaging lens meet f×TAN(FOV/2)>4.0 mm; and
the total effective focal length f of the optical imaging lens, a center thickness CT 7 of the seventh lens on the optical axis and a center thickness CT 8 of the eighth lens on the optical axis meet:
f/(CT 7 +CT 8 )≥5.0;
the total effective focal length f of the optical imaging lens, a curvature radius R 13 of an object-side surface of the seventh lens and a curvature radius R 14 of an image-side surface of the seventh lens meet:
f/R 13 +f/R 14 >3.5.
2. The optical imaging lens as claimed in claim 1 , wherein a distance TTL from an object-side surface of the first lens to an imaging surface S of the optical imaging lens on the optical axis and an Entrance Pupil Diameter (EPD) of the optical imaging lens meet:
TTL/EPD≤2.0.
3. The optical imaging lens as claimed in claim 1 , wherein the total effective focal length f of the optical imaging lens and a curvature radius R 2 of an image-side surface of the first lens meet:
f/R 2 >1.5.
4. The optical imaging lens as claimed in claim 1 , wherein the total effective focal length f of the optical imaging lens and a curvature radius R 10 of an image-side surface of the fifth lens meet:
f/R 10 <−0.5.
5. The optical imaging lens as claimed in claim 1 , wherein a curvature radius R 3 of an object-side surface of the second lens and a curvature radius R 4 of an image-side surface of the second lens meet: −10<R 4 /R 3 <−3.0.
6. The optical imaging lens as claimed in claim 1 , wherein a curvature radius R 15 of an object-side surface of the eighth lens and a curvature radius R 16 of an image-side surface of the eighth lens meet:
1<R 15 /R 16 <2.
7. The optical imaging lens as claimed in claim 1 , wherein the total effective focal length f of the optical imaging lens, an effective focal length f3 of the third lens, and an effective focal length f8 of the eighth lens meet:
|f/f3−f/f8|<0.5.
8. The optical imaging lens as claimed in claim 1 , wherein an effective focal length f5 of the fifth lens and an effective focal length f4 of the fourth lens meet: −5.0<f5/f4<0.
9. The optical imaging lens as claimed in claim 1 , wherein an effective focal length f7 of the seventh lens and a combined focal length f12 of the first lens and the second lens meet 1.5<f7/f12<5.0.
10. The optical imaging lens as claimed in claim 1 , wherein a total effective focal length f of the optical imaging lens and an effective focal length f1 of the first lens meet f/|f1|≤0.3.
11. The optical imaging lens as claimed in claim 1 , wherein an abbe number V4 of the fourth lens, an abbe number V5 of the fifth lens and an abbe number V6 of the sixth lens meet 30<(V4+V5+V6)/3<40.
12. The optical imaging lens as claimed in claim 1 , wherein a total effective focal length f of the optical imaging lens and an EPD of the optical imaging lens meet f/EPD≤1.5.