Camera optical lens

1. A camera optical lens comprising eight lenses, from an object side to an image side in sequence: a first lens having a positive refractive power, a second lens having a negative refractive power, a third lens having a positive refractive power, a fourth lens having a positive refractive power, a fifth lens having a negative refractive power, a sixth lens having a positive refractive power, a seventh lens having a negative refractive power, and an eighth lens having a negative refractive power; wherein the first lens includes an image-side surface being concave in the paraxial region, the fourth lens includes an object-side surface being convex in a paraxial region and an image-side surface being concave in the paraxial region; wherein the camera optical lens satisfies the following conditions:

0.95≤ f/TTL;

f/IH≥ 2.25;

−4.00≤ f 2/ f≤− 1.80; and

3.00≤( R 13+ R 14)/( R 13− R 14)≤25.00;

where

TTL denotes a total optical length from an object-side surface of the first lens to an image surface of the camera optical lens along an optical axis;

IH denotes an image height of the camera optical lens;

f denotes a focal length of the camera optical lens;

f2 denotes a focal length of the second lens;

R13 denotes a central curvature radius of an object-side surface of the seventh lens; and

R14 denotes a central curvature radius of an image-side surface of the seventh lens.

2. The camera optical lens according to claim 1 , wherein the camera optical lens further satisfies the following condition:

4.00≤ f 4/ f≤ 14.50;

where

f4 denotes a focal length of the fourth lens.

3. The camera optical lens according to claim 1 , wherein the camera optical lens further satisfies the following conditions:

0.70≤ f 1/ f≤ 2.50;

−10.31≤( R 1+ R 2)/( R 1− R 2)≤−2.82; and

0.04≤ d 1/ TTL≤ 0.16;

where

f1 denotes a focal length of the first lens;

R1 denotes a central curvature radius of an object-side surface of the first lens;

R2 denotes a central curvature radius of an image-side surface of the first lens; and

d1 denotes an on-axis thickness of the first lens.

4. The camera optical lens according to claim 1 , wherein the camera optical lens further satisfies the following conditions:

3.09≤( R 3+ R 4)/( R 3− R 4)≤19.51; and

0.02≤ d 3/ TTL≤ 0.05;

where

R3 denotes a central curvature radius of an object-side surface of the second lens;

R4 denotes a central curvature radius of an image-side surface of the second lens; and

d3 denotes an on-axis thickness of the second lens.

5. The camera optical lens according to claim 1 , wherein the camera optical lens further satisfies the following conditions:

0.57,13≤ f 3/ f≤ 1.75;

−3.46≤ R 5+ R 6)/( R 5− R 6)≤−1.07; and

0.05≤ d 5/ TTL≤ 0.19;

where

f3 denotes a focal length of the third lens;

R5 denotes a central curvature radius of an object-side surface of the third lens;

R6 denotes a central curvature radius of an image-side surface of the third lens; and

d5 denotes an on-axis thickness of the third lens.

6. The camera optical lens according to claim 1 , wherein the camera optical lens further satisfies the following conditions:

−472.75≤( R 7+ R 8)/( R 7− R 8)≤−10.65; and

0.02≤ d 7/ TTL≤ 0.05;

where

R7 denotes a central curvature radius of an object-side surface of the fourth lens;

R8 denotes a central curvature radius of an image-side surface of the fourth lens; and

d7 denotes an on-axis thickness of the fourth lens.

7. The camera optical lens according to claim 1 , wherein the camera optical lens further satisfies the following conditions:

−8.95≤ f 5/ f≤− 1.82;

0.44≤( R 9+ R 10)/( R 9− R 10)≤10.14; and

0.02≤ d 9/ TTL≤ 0.06;

where

f5 denotes a focal length of the fifth lens;

R9 denotes a central curvature radius of an object-side surface of the fifth lens;

R10 denotes a central curvature radius of an image-side surface of the fifth lens; and

d9 denotes an on-axis thickness of the fifth lens.

8. The camera optical lens according to claim 1 , wherein the camera optical lens further satisfies the following conditions:

1.76≤ f 6/ f≤ 13.06;

1.45≤( R 11+ R 12)/( R 11− R 12)≤25.66; and

0.03≤ d 11/ TTL≤ 0.09;

where

f6 denotes a focal length of the sixth lens;

R11 denotes a central curvature radius of an object-side surface of the sixth lens;

R12 denotes a central curvature radius of an image-side surface of the sixth lens; and

d11 denotes an on-axis thickness of the sixth lens.

9. The camera optical lens according to claim 1 , wherein the camera optical lens further satisfies the following conditions:

−43.51≤ f 7/ f≤− 1.26; and

0.03≤ d 13/ TTL≤ 0.09;

where

f7 denotes a focal length of the seventh lens; and

d13 denotes an on-axis thickness of the seventh lens.

10. The camera optical lens according to claim 1 , wherein the camera optical lens further satisfies the following conditions:

−4.22≤ f 8/ f≤− 0.86;

−2.85≤( R 15+ R 16)/( R 15− R 16)≤−0.40; and

0.03≤ d 15/ TTL≤ 0.10;

where

f8 denotes a focal length of the eighth lens;

R15 denotes a central curvature radius of an object-side surface of the eighth lens;

R16 denotes a central curvature radius of an image-side surface of the eighth lens; and

d15 denotes an on-axis thickness of the eighth lens.