Imaging system lens assembly, image capturing unit and electronic device
An imaging system lens assembly includes a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element and a sixth lens element in order from an object side to an image side along an optical path. Each of the six lens elements has an object-side surface facing toward the object side and an image-side surface facing toward the image side. The first lens element has positive refractive power. The fifth lens element has positive refractive power. The image-side surface of the fifth lens element is concave in a paraxial region thereof. The image-side surface of the sixth lens element has at least one inflection point. A central thickness of the first lens element is a maximum among central thicknesses of all lens elements of the imaging system lens assembly.
1. An imaging system lens assembly comprising six lens elements, the six lens elements being, in order from an object side to an image side along an optical path, a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element and a sixth lens element, and each of the six lens elements having an object-side surface facing toward the object side and an image-side surface facing toward the image side;
wherein the first lens element has positive refractive power, the second lens element has negative refractive power, the fourth lens element has negative refractive power, the fifth lens element has positive refractive power, the image-side surface of the fifth lens element is concave in a paraxial region thereof, the sixth lens element has negative refractive power, the image-side surface of the sixth lens element has at least one inflection point, and a central thickness of the first lens element is a maximum among central thicknesses of all lens elements of the imaging system lens assembly;
wherein the imaging system lens assembly further comprises an aperture stop, a curvature radius of the object-side surface of the first lens element is R1, a curvature radius of the image-side surface of the sixth lens element is R12, an Abbe number of the second lens element is V2, an Abbe number of the third lens element is V3, an Abbe number of the fourth lens element is V4, an axial distance between the aperture stop and the image-side surface of the sixth lens element is SD, an axial distance between the object-side surface of the first lens element and the image-side surface of the sixth lens element is TD, an axial distance between the first lens element and the second lens element is T12, an axial distance between the fourth lens element and the fifth lens element is T45, an axial distance between the fifth lens element and the sixth lens element is T56, and the following conditions are satisfied:
0.80<( R 1+ R 12)/( R 1− R 12)<4.00;
0.30<( V 2+ V 3)/ V 4<1.30;
0.92< SD/TD< 1.20; and
0.20≤( T 12+ T 45)/ T 56<5.00.
2. The imaging system lens assembly of claim 1 , wherein the image-side surface of the first lens element is convex in a paraxial region thereof, and the object-side surface of the fifth lens element is convex in a paraxial region thereof.
3. The imaging system lens assembly of claim 1 , wherein an f-number of the imaging system lens assembly is Fno, and the following condition is satisfied:
1.50< Fno< 2.00.
4. The imaging system lens assembly of claim 1 , wherein an entrance pupil diameter of the imaging system lens assembly is EPD, an axial distance between the image-side surface of the sixth lens element and an image surface is BL, and the following condition is satisfied:
1.20< EPD/BL< 4.00.
5. The imaging system lens assembly of claim 1 , wherein a maximum effective radius of the object-side surface of the first lens element is Y1R1, a distance in parallel with an optical axis between a maximum effective radius position of the object-side surface of the first lens element and a maximum effective radius position of the image-side surface of the first lens element is ET1, a maximum field of view of the imaging system lens assembly is FOV, and the following conditions are satisfied:
0.50< Y 1 R 1/ ET 1<2.00; and
86.0 degrees< FOV< 130.0 degrees.
6. The imaging system lens assembly of claim 1 , wherein a curvature radius of the object-side surface of the fourth lens element is R7, a curvature radius of the image-side surface of the fourth lens element is R8, and the following condition is satisfied:
−50.00<( R 7+ R 8)/( R 7− R 8)<0.00.
7. The imaging system lens assembly of claim 1 , wherein an axial distance between the object-side surface of the first lens element and an image surface is TL, a maximum image height of the imaging system lens assembly is ImgH, and the following condition is satisfied:
0.10 <TL /ImgH<1.50.
8. The imaging system lens assembly of claim 1 , wherein a focal length of the imaging system lens assembly is f, a focal length of the first lens element is f1, a focal length of the second lens element is f2, a focal length of the third lens element is f3, a focal length of the fourth lens element is f4, a focal length of the fifth lens element is f5, a focal length of the sixth lens element is f6, and the following condition is satisfied:
0.20<(| f/f 1|+| f/f 6|)/(| f/f 2|+| f/f 3|+| f/f 4|+| f/f 5|)<1.10.
9. An image capturing unit comprising:
the imaging system lens assembly of claim 1 ; and
an image sensor disposed on an image surface of the imaging system lens assembly.
10. An electronic device comprising:
the image capturing unit of claim 9 .
11. An imaging system lens assembly comprising six lens elements, the six lens elements being, in order from an object side to an image side along an optical path, a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element and a sixth lens element, and each of the six lens elements having an object-side surface facing toward the object side and an image-side surface facing toward the image side;
wherein the first lens element has positive refractive power, the object-side surface of the first lens element is convex in a paraxial region thereof, the image-side surface of the first lens element is convex in a paraxial region thereof, the second lens element has negative refractive power, the fifth lens element has positive refractive power, the sixth lens element has negative refractive power, and the image-side surface of the sixth lens element has at least one inflection point;
wherein a central thickness of the first lens element is CT1, a maximum value among central thicknesses of the second lens element to the sixth lens element is max (CT2-6), a focal length of the imaging system lens assembly is f, a composite focal length of the first lens element, the second lens element, the third lens element and the fourth lens element is f1234, a composite focal length of the fifth lens element and the sixth lens element is f56, a refractive index of the fourth lens element is N4, a refractive index of the fifth lens element is N5, a curvature radius of the image-side surface of the fourth lens element is R8, a curvature radius of the object-side surface of the fifth lens element is R9, an axial distance between the fourth lens element and the fifth lens element is T45, an Abbe number of the third lens element is V3, an Abbe number of the fourth lens element is V4, a maximum field of view of the imaging system lens assembly is FOV, and the following conditions are satisfied:
1.40< CT 1/max( CT 2−6)<5.00;
0.60< f /fair45<3.00, wherein 1/fair45=[(1− N 4)/( N 5× R 8)− F ( N 5−1)/( N 5× R 9)]−{[(1− N 4)×( N 5−1)× T 45]/( N 5× R 8× R 9)};
0.45< V 3/ V 4<0.90;
86.0 degrees< FOV< 130.0 degrees; and
0.40< f 1234/ f 56<5.00.
12. The imaging system lens assembly of claim 11 , wherein the object-side surface of the second lens element is convex in a paraxial region thereof, the image-side surface of the second lens element is concave in a paraxial region thereof, and the image-side surface of the fifth lens element is concave in a paraxial region thereof.
13. The imaging system lens assembly of claim 11 , wherein a focal length of the first lens element is f1, a focal length of the fourth lens element is f4, and the following condition is satisfied:
−30.00< f 4/ f 1<10.00.
14. The imaging system lens assembly of claim 11 , wherein a curvature radius of the object-side surface of the sixth lens element is R11, a curvature radius of the image-side surface of the sixth lens element is R12, and the following condition is satisfied:
2.00<( R 11+ R 12)/( R 11− R 12)<13.00.
15. The imaging system lens assembly of claim 11 , wherein a distance in parallel with an optical axis between a maximum effective radius position of the object-side surface of the first lens element and a maximum effective radius position of the image-side surface of the first lens element is ET1, the central thickness of the first lens element is CT1, and the following condition is satisfied:
0.50< ET 1/ CT 1<2.00.
16. The imaging system lens assembly of claim 11 , wherein a maximum effective radius of the object-side surface of the first lens element is Y1R1, a maximum image height of the imaging system lens assembly is ImgH, and the following condition is satisfied:
0.10< Y 1 R 1/ImgH<0.40.
17. The imaging system lens assembly of claim 11 , wherein the composite focal length of the first lens element, the second lens element, the third lens element and the fourth lens element is f1234, the composite focal length of the fifth lens element and the sixth lens element is f56, and the following condition is satisfied:
0.80< f 1234/ f 56<3.50.
18. The imaging system lens assembly of claim 11 , wherein the axial distance between the fourth lens element and the fifth lens element is T45, a sum of axial distances between each of all adjacent lens elements of the imaging system lens assembly is ΣAT, and the following condition is satisfied:
0.01 <T 45 /ΣAT< 0.10.
19. An imaging system lens assembly comprising six lens elements, the six lens elements being, in order from an object side to an image side along an optical path, a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element and a sixth lens element, and each of the six lens elements having an object-side surface facing toward the object side and an image-side surface facing toward the image side;
wherein the first lens element has positive refractive power, the second lens element has negative refractive power, the fifth lens element has positive refractive power, the image-side surface of the fifth lens element is concave in a paraxial region thereof, the sixth lens element has negative refractive power, the image-side surface of the sixth lens element has at least one inflection point, and a central thickness of the first lens element is a maximum among central thicknesses of all lens elements of the imaging system lens assembly;
wherein an f-number of the imaging system lens assembly is Fno, a curvature radius of the object-side surface of the first lens element is R1, a curvature radius of the image-side surface of the sixth lens element is R12, a maximum effective radius of the object-side surface of the first lens element is Y1R1, a distance in parallel with an optical axis between a maximum effective radius position of the object-side surface of the first lens element and a maximum effective radius position of the image-side surface of the first lens element is ET1, a focal length of the fifth lens element is f5, a focal length of the sixth lens element is f6, and the following conditions are satisfied:
1.50< Fno< 2.10;
1.20<( R 1+ R 12)/( R 1− R 12)<3.00;
0.50< Y 1 R 1/ ET 1<2.00; and
−1.00< f 5/ f 6<1.00.
20. The imaging system lens assembly of claim 19 , wherein the image-side surface of the first lens element is convex in a paraxial region thereof, and the image-side surface of the third lens element is concave in a paraxial region thereof.
21. The imaging system lens assembly of claim 19 , wherein a curvature radius of the image-side surface of the fifth lens element is R10, a curvature radius of the object-side surface of the sixth lens element is R11, and the following condition is satisfied:
−0.10< R 11/ R 10<0.25.
22. The imaging system lens assembly of claim 19 , wherein the fourth lens element has negative refractive power;
wherein an axial distance between the first lens element and the second lens element is T12, an axial distance between the fourth lens element and the fifth lens element is T45, an axial distance between the fifth lens element and the sixth lens element is T56, and the following condition is satisfied:
0.20≤( T 12+ T 45)/ T 56<5.00.
23. The imaging system lens assembly of claim 19 , wherein a maximum field of view of the imaging system lens assembly is FOV, and the following condition is satisfied:
86.0 degrees< FOV< 130.0 degrees.
24. The imaging system lens assembly of claim 19 , wherein the central thickness of the first lens element is CT1, a central thickness of the second lens element is CT2, and the following condition is satisfied:
3.50< CT 1/ CT 2<8.00.
25. The imaging system lens assembly of claim 19 , wherein the focal length of the fifth lens element is f5, the focal length of the sixth lens element is f6, and the following condition is satisfied:
−1.00< f 5/ f 6<0.00.
26. The imaging system lens assembly of claim 19 , wherein a curvature radius of the object-side surface of the third lens element is R5, a curvature radius of the image-side surface of the third lens element is R6, and the following condition is satisfied:
−20.00<( R 5+ R 6)/( R 5− R 6)<80.00.