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 negative refractive power, a fourth lens having a negative refractive power, a fifth lens having a negative refractive power, a sixth lens having a positive refractive power, a seventh lens, and an eighth lens having a negative refractive power; wherein the camera optical lens satisfies the following conditions:

0.95≤ f/TTL;

−4.00≤ f 2/ f≤− 1.80; and

−20.00≤( R 15+ R 16/( R 15− R 16)≤−3.00;

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;

f denotes a focal length of the camera optical lens;

f2 denotes a focal length of the second lens;

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

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

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

0.90≤ f 6/ f≤ 2.50;

where

f6 denotes a focal length of the sixth lens.

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

0.23≤ f 1/ f≤ 0.72;

−1.61≤( R 1+ R 2)/( R 1− R 2)≤−0.47; and

0.05≤ d 1/ TTL≤ 0.20;

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:

−2.33≤(R3+R4)/(R3−R4)≤−0.30; and

0.02≤d3/TTL≤0.06;

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:

−4.05≤ f 3/ f≤− 1.07;

0.67≤( R 5+ R 6)/( R 5− R 6)≤4.48; and

0.02≤ d 5/ TTL≤ 0.06;

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:

−4.46≤ f 4/ f≤− 0.99;

1.68≤( R 7+ R 8)/( R 7− R 8)≤8.60; and

0.02≤ d 7/ TTL≤ 0.06;

where

f4 denotes a focal length of the fourth lens;

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:

−5.33≤ f 5/ f≤− 1.45;

−9.27≤( R 9+ R 10)/( R 9− R 10)≤−2.42; 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:

−14.57≤( R 11+ R 12)/( R 11− R 12)≤−0.78; and

0.02≤ d 11/ TTL≤ 0.13;

where

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:

−2.37≤ f 7/ f≤ 127.2;

−133.01≤( R 13+ R 14)/( R 13− R 14)≤−0.37; and

0.04≤ d 13/ TTL≤ 0.20;

where

f7 denotes a focal length of the seventh lens;

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

R14 denotes a central curvature radius of an image-side surface 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:

−56.04≤ f 8/ f≤− 1.17; and

0.03≤ d 15/ TTL≤ 0.13;

where

f8 denotes a focal length of the eighth lens; and

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

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

f/IH≥ 2.00,

where IH denotes an image height of the camera optical lens.