Optical lens

An optical lens having an optical axis, the optical lens comprising:

• a first lens having a positive refractive power, and comprising a first surface and a second surface facing away from the first surface;
• a second lens having a positive refractive power or a negative refractive power, and comprising a third surface and a fourth surface facing away from the third surface;
• a third lens having a positive refractive power, and comprising a fifth surface and a sixth surface facing away from the fifth surface;
• a fourth lens having a negative refractive power, and comprising a seventh surface and an eighth surface facing away from the seventh surface;
• a fifth lens having a positive refractive power, and comprising a ninth surface and a tenth surface facing away from the ninth surface;
• a sixth lens having a negative refractive power, and comprising an eleventh surface and a twelfth surface facing away from the eleventh surface;
• and
• an image plane;
• wherein the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the image plane are arranged in that sequence from object-side to image-side along the optical axis;
• the first surface, the second surface, the third surface, the fourth surface, the fifth surface, the sixth surface, the seventh surface, the eighth surface, the ninth surface, the tenth surface, the eleventh surface, and twelfth surface are arranged in that sequence from object-side to image-side;
• the optical lens satisfies the following conditions:
• 21.3°<SA4<24.7°;
• 59°<SA6+X<68°, and X=arctan(SD6/ED64);
• 81°<SA8+Y<89°, and Y=arctan(SD8/ED86);
• 0.67<(T2*T3)/(T4*A2)<0.96;
• wherein SA4 denotes an angle between a tangent at an end portion of the fourth surface and the image plane, SA6 denotes an angle between a tangent at an end portion of the sixth surface and the image plane, SA8 denotes an angle between a tangent at an end portion of the eighth surface and the image plane, SD6 denotes a distance of the sixth surface from the end portion of the sixth surface to the optical axis, ED64 denotes a distance from the end portion of the sixth surface to the end portion of the fourth surface along an extending direction of the optical axis, SD8 denotes a distance of the eighth surface from the end portion of the eighth surface to the optical axis, and ED86 denotes a distance from the end portion of the eighth surface to the end portion of the sixth surface along the extending direction, T2 denotes a center thickness of the second lens, T3 denotes a center thickness of the third lens, T4 denotes a center thickness of the fourth lens, and A2 denotes a distance from the second lens to the third lens along the optical axis.