[ detailed description ] embodiments
The invention is further described with reference to the following figures and embodiments.
In order to make the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, it will be appreciated by those of ordinary skill in the art that numerous technical details are set forth in order to provide a better understanding of the present invention in its various embodiments. However, the technical solution claimed in the present invention can be implemented without these technical details and various changes and modifications based on the following embodiments.
The following is an embodiment one:
referring to fig. 1 to 4, an imaging optical lens 10 according to a first embodiment of the present invention is provided. In fig. 1, the left side is an object side, and the right side is an image side, the imaging optical lens system 10 mainly includes five coaxially disposed lenses, namely, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4 and a fifth lens L5 in order from the object side to the image side. A stop S1 is further provided on the object-side surface of the first lens L1, and a glass plate GF is provided between the fifth lens L5 and the image plane Si, where the glass plate GF may be a glass cover plate or an optical filter.
In this embodiment, the first lens element L1 with positive refractive power has a convex object-side surface and a planar image-side surface; the second lens element L2 with negative refractive power has a planar object-side surface and a concave image-side surface; the third lens element L3 with positive refractive power has a concave object-side surface and a convex image-side surface; the fourth lens element L4 with positive refractive power has a concave object-side surface and a convex image-side surface; the fifth lens element L5 with negative refractive power has a concave object-side surface and a convex image-side surface.
The focal length of the entire imaging optical lens 10 is f in millimeters (mm), the focal length of the first lens L1 is f1 in millimeters (mm), the focal length of the third lens L3 is f3 in millimeters (mm), the radius of curvature of the image-side surface of the second lens L2 is R2, the radius of curvature of the object-side surface of the fifth lens L5 is R9, and the radius of curvature of the image-side surface of the fifth lens L5 is R10. f. f1, f3, R2, R9 and R10 satisfy the following relationships:
5.10≤R2/f≤5.20 (1)
3.40≤R9/R10≤3.50 (2)
8.30≤(f1+f3)/f≤8.50 (3)
the shape and refractive power of the first lens L1 are defined by the conditional expression (1), and the degree of deflection of the light rays passing through the imaging optical lens can be reduced within the range defined by the conditional expression (1), thereby effectively reducing aberrations.
The conditional expression (2) defines the shape of the fifth lens L5, and within the range defined by the conditional expression (2), the degree of deflection of the light rays passing through the imaging optical lens can be reduced, and aberration can be effectively reduced.
The conditional expression (3) specifies the ratio of the sum of the focal length of the first lens L1 and the focal length of the third lens L3 to the focal length of the image pickup optical lens, and within the range specified by the conditional expression (3), the focal powers of the first lens L1 and the third lens L3 can be effectively distributed to correct the aberration of the image pickup optical lens, thereby improving the image quality.
In the present embodiment, the focal length of the second lens L2 is f2, the focal length of the fifth lens L5 is f5, and f2, f5, and f satisfy the following relations:
-2.00≤(f2+f5)/f≤-1.90 (4)
the conditional expression (4) specifies the ratio of the sum of the focal length of the second lens L2 and the focal length of the fifth lens L5 to the focal length of the image-taking optical lens, and within the range specified by the conditional expression (4), the focal powers of the second lens L2 and the fifth lens L5 can be effectively distributed to correct the aberration of the image-taking optical lens 10, thereby improving the image quality.
In the present embodiment, the focal length f3 of the third lens L3 and the focal length f of the entire imaging optical lens satisfy the following relationship:
3.77≤f3/f≤11.46 (5)
when f3/f satisfies the conditional expression (5), the focal power of the third lens L3 can be effectively distributed, and the aberration of the image pickup optical lens is corrected, thereby improving the imaging quality.
In addition, the radius of curvature of the object-side surface of the third lens L3 is R5, the radius of curvature of the image-side surface of the third lens L3 is R6, and R5 and R6 satisfy the following relational expressions:
-14.97≤(R5+R6)/(R5-R6)≤-4.35 (6)
conditional expression (6) specifies the shape of the third lens L3, and within the range specified by conditional expression (6), the degree of deflection of the light rays passing through the imaging optical lens can be reduced, and aberration can be effectively reduced.
In addition, in the imaging optical lens 10 provided in the present embodiment, the surface of each lens can be an aspheric surface, which is easy to be made into a shape other than a spherical surface, so as to obtain more control variables for reducing the aberration and further reducing the number of lenses used, thereby effectively reducing the total length of the imaging optical lens 10. In the present embodiment, both the object-side surface and the image-side surface of each lens are aspheric.
It is to be noted that since the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, and the fifth lens L5 have the structure and the parameter relationship as described above, the image-taking optical lens 10 can reasonably distribute the power, the interval, and the shape of each lens, and thus correct various kinds of aberrations.
In the present embodiment: TTL/IH is equal to or less than 1.44, and FNO is equal to or less than 2.07, where TTL is the optical length of the image pickup optical lens 10, IH is the image height of the image pickup optical lens 10, and FNO is the focal number, i.e., the ratio of the effective focal length to the entrance pupil aperture. In this way, the imaging optical lens 10 can satisfy design requirements for a large aperture and an ultra-thin structure while having good optical imaging performance.
In addition, at least one of the object-side surface and the image-side surface of each lens may further have an inflection point and/or a stagnation point, so as to meet the requirement of high-quality imaging.
The following shows design data of the image pickup optical lens 10 shown in fig. 1.
Table 1 shows the object-side and image-side radii of curvature R, the on-axis thicknesses of the respective lenses, the distances d between the adjacent lenses, the refractive indices nd, and the abbe numbers ν d of the first lens L1 to the fifth lens L5 constituting the imaging optical lens 10 according to the first embodiment of the present invention. In the present embodiment, R and d are both expressed in units of millimeters (mm).
[ TABLE 1 ]
The meanings of the symbols in the above table are as follows.
R: the radius of curvature of the optical surface; s1: an aperture; r1: the object side of the first lens L1; r2: the image-side surface of the first lens L1; r3: the object side of the second lens L2; r4: the image-side surface of the second lens L2; r5: the object side of the third lens L3; r6: the image-side surface of the third lens L3; r7: the object-side surface of the fourth lens L4; r8: the image-side surface of the fourth lens L4; r9: the object-side surface of the fifth lens L5; r10: the image-side surface of the fifth lens L5; r11 object side of glass plate GF; r12 image side of glass plate GF;
d: the on-axis thickness of each lens or the on-axis distance between two adjacent lenses; d0 on-axis distance from the stop S1 to the object-side surface of the first lens L1; d 1: the on-axis thickness of the first lens L1; d 2: the on-axis distance from the image-side surface of the first lens L1 to the object-side surface of the second lens L2; d 3: the on-axis thickness of the second lens L2; d 4: the on-axis distance from the image-side surface of the second lens L2 to the object-side surface of the third lens L3; d 5: the on-axis thickness of the third lens L3; d 6: the on-axis distance from the image-side surface of the third lens L3 to the object-side surface of the fourth lens L4; d 7: the on-axis thickness of the fourth lens L4; d 8: an on-axis distance from an image-side surface of the fourth lens L4 to an object-side surface of the fifth lens L5; d 9: the on-axis thickness of the fifth lens L5; d 10: the on-axis distance from the image-side surface of the fifth lens L5 to the object-side surface of the glass plate GF; d 11: on-axis thickness of glass flat GF; d 12: the axial distance from the image side surface of the glass flat GF to the image surface Si;
nd: a refractive index; nd 1: the refractive index of the first lens L1; nd 2: the refractive index of the second lens L2; nd 3: refractive index of the third lens L3; nd 4: refractive index of the fourth lens L4; nd 5: the refractive index of the fifth lens L5; ndg: refractive index of glass plate GF;
vd is Abbe number; v 1: abbe number of the first lens L1; v 2: abbe number of the second lens L2; v 3: abbe number of the third lens L3; v 4: abbe number of the fourth lens L4; v 5: abbe number of the fifth lens L5; vg: abbe number of glass sheet GF.
[ TABLE 2 ]
In table 2, k is a conic coefficient, and a4, a6, A8, a10, a12, a14, a16, a18, a20 are aspherical coefficients.
[ TABLE 3 ]
[ TABLE 4 ]
|
Number of stagnation points
|
Location of stagnation 1
|
Location of stagnation 2
|
P1R1
|
0
|
0
|
0
|
P1R2
|
1
|
0.695
|
0
|
P2R1
|
1
|
0.525
|
0
|
P2R2
|
0
|
0
|
0
|
P3R1
|
1
|
0.465
|
0
|
P3R2
|
2
|
0.475
|
1.085
|
P4R1
|
0
|
0
|
0
|
P4R2
|
0
|
0
|
0
|
P5R1
|
1
|
0.345
|
0
|
P5R2
|
1
|
1.075
|
0 |
Tables 3 and 4 show the inflection point and the stagnation point design data of each lens in the imaging optical lens 10 of the present embodiment. P1R1 and P1R2 represent the object-side surface and the image-side surface of the first lens L1, P2R1 and P2R2 represent the object-side surface and the image-side surface of the second lens L2, P3R1 and P3R2 represent the object-side surface and the image-side surface of the third lens L3, P4R1 and P4R2 represent the object-side surface and the image-side surface of the fourth lens L4, and P5R1 and P5R2 represent the object-side surface and the image-side surface of the fifth lens L5, respectively. The "inflection point position" field correspondence data is a vertical distance from an inflection point set on each lens surface to the optical axis of the image pickup optical lens 10. The "stagnation point position" field corresponding data is the vertical distance from the stagnation point set on each lens surface to the optical axis of the imaging optical lens 10.
Table 17 below also lists values corresponding to various parameters in the first embodiment and the parameters specified in the conditional expressions.
Fig. 2 and 3 show schematic diagrams of axial aberration and chromatic aberration of magnification of light having wavelengths of 656nm, 588nm, 546nm, 486nm, and 436nm passing through the imaging optical lens 10, respectively. Fig. 4 is a schematic view showing the curvature of field and distortion of light having a wavelength of 546nm after passing through the imaging optical lens 10. The field curvature S in fig. 4 is a field curvature in the sagittal direction, and T is a field curvature in the meridional direction.
In the present embodiment, the image height of the imaging optical lens 10 is IH, the field angle is FOV, and the entrance pupil diameter is ENPD, where IH is 3.188mm, the diagonal FOV is 77.31deg, and ENPD is 1.905, so that the imaging optical lens 10 has a large aperture, an ultrathin size, a wide angle, and excellent imaging performance.
The following is embodiment two:
fig. 5 is a schematic structural diagram of the image pickup optical lens 20 in the second embodiment, which is basically the same as the first embodiment, and the meanings of symbols in the following list are also the same as those in the first embodiment, so that the description of the same parts is omitted here, and only different points are listed below.
Tables 5 and 6 show design data of the imaging optical lens 20 according to the second embodiment of the present invention.
[ TABLE 5 ]
[ TABLE 6 ]
Tables 7 and 8 show the inflected point and stagnation point design data of each lens in the imaging optical lens 20.
[ TABLE 7 ]
[ TABLE 8 ]
|
Stationed pointNumber of
|
Location of stagnation 1
|
Location of stagnation 2
|
Location of stagnation 3
|
P1R1
|
0
|
0
|
0
|
0
|
P1R2
|
1
|
0.605
|
0
|
0
|
P2R1
|
1
|
0.525
|
0
|
0
|
P2R2
|
0
|
0
|
0
|
0
|
P3R1
|
2
|
0.505
|
0.955
|
0
|
P3R2
|
1
|
0.515
|
0
|
0
|
P4R1
|
0
|
0
|
0
|
0
|
P4R2
|
0
|
0
|
0
|
0
|
P5R1
|
3
|
0.355
|
2.235
|
2.285
|
P5R2
|
1
|
1.085
|
0
|
0 |
Table 17 below also lists values corresponding to various parameters in embodiment two and the parameters specified in the conditional expressions.
Fig. 6 and 7 show schematic diagrams of axial aberration and chromatic aberration of magnification after light with wavelengths of 656nm, 588nm, 546nm, 486nm and 436nm passes through the imaging optical lens 20, respectively. Fig. 8 is a schematic view showing the curvature of field and distortion of light having a wavelength of 546nm after passing through the imaging optical lens 20. The field curvature S in fig. 8 is a field curvature in the sagittal direction, and T is a field curvature in the tangential direction.
In the present embodiment, the image height of the imaging optical lens 20 is IH, the field angle is FOV, and the entrance pupil diameter is ENPD, where IH is 3.188mm, the diagonal FOV is 77.00deg, and ENPD is 1.905, so that the imaging optical lens 20 has a large aperture, an ultrathin size, a wide angle, and excellent imaging performance.
The following is the third embodiment:
fig. 9 is a schematic structural diagram of an imaging optical lens 30 in the third embodiment, which is basically the same as the first embodiment, and the meanings of symbols in the following list are also the same as those in the first embodiment, so that the description of the same parts is omitted here, and only different points are listed below.
Tables 9 and 10 show design data of the imaging optical lens 30 according to the third embodiment of the present invention.
[ TABLE 9 ]
[ TABLE 10 ]
Tables 11 and 12 show the inflected point and stagnation point design data of each lens in the imaging optical lens 30.
[ TABLE 11 ]
[ TABLE 12 ]
|
Number of stagnation points
|
Location of stagnation 1
|
Location of stagnation 2
|
Location of stagnation 3
|
P1R1
|
0
|
0
|
0
|
0
|
P1R2
|
1
|
0.615
|
0
|
0
|
P2R1
|
1
|
0.525
|
0
|
0
|
P2R2
|
0
|
0
|
0
|
0
|
P3R1
|
1
|
0.505
|
0
|
0
|
P3R2
|
1
|
0.515
|
0
|
0
|
P4R1
|
0
|
0
|
0
|
0
|
P4R2
|
0
|
0
|
0
|
0
|
P5R1
|
3
|
0.345
|
2.215
|
2.315
|
P5R2
|
1
|
1.095
|
0
|
0 |
Table 17 below also lists values corresponding to various parameters in the third embodiment and the parameters specified in the conditional expressions.
Fig. 10 and 11 show schematic diagrams of axial aberration and chromatic aberration of magnification of light having wavelengths of 656nm, 588nm, 546nm, 486nm, and 436nm passing through the imaging optical lens 30, respectively. Fig. 12 is a schematic view showing the curvature of field and distortion of light having a wavelength of 546nm after passing through the imaging optical lens 30.
The field curvature S in fig. 12 is a field curvature in the sagittal direction, and T is a field curvature in the tangential direction.
In the present embodiment, the image height of the imaging optical lens 30 is IH, the field angle is FOV, and the entrance pupil diameter is ENPD, where IH is 3.188mm, the diagonal FOV is 77.00deg, and ENPD is 1.905, so that the imaging optical lens 30 has a large aperture, an ultrathin size, a wide angle, and excellent imaging performance.
The following is embodiment four:
fig. 13 is a schematic structural diagram of an image pickup optical lens 40 in a fourth embodiment, which is basically the same as the first embodiment, and the meanings of symbols in the following list are also the same as those in the first embodiment, so that the same parts are not repeated herein, and only different points are listed below.
Tables 13 and 14 show design data of the imaging optical lens 40 according to the fourth embodiment of the present invention.
[ TABLE 13 ]
[ TABLE 14 ]
Tables 15 and 16 show the inflected point and stagnation point design data of each lens in the imaging optical lens 40.
[ TABLE 15 ]
[ TABLE 16 ]
Table 17 below also lists values corresponding to various parameters in the fourth embodiment and the parameters specified in the conditional expressions.
Fig. 14 and 15 show schematic diagrams of axial aberration and chromatic aberration of magnification of light having wavelengths of 656nm, 588nm, 546nm, 486nm, and 436nm passing through the imaging optical lens 40, respectively. Fig. 16 is a schematic view showing the curvature of field and distortion of light having a wavelength of 546nm after passing through the imaging optical lens 40. The field curvature S in fig. 16 is a field curvature in the sagittal direction, and T is a field curvature in the tangential direction.
In the present embodiment, the image height of the imaging optical lens 40 is IH, the field angle is FOV, and the entrance pupil diameter is ENPD, where IH is 3.188mm, the diagonal FOV is 76.85deg, and ENPD is 1.905, so that the imaging optical lens 40 has a large aperture, an ultrathin size, a wide angle, and excellent imaging performance.
Table 17 below lists values corresponding to conditional expressions (1), (2), (3), and (4) in the first embodiment, the second embodiment, the third embodiment, and the fourth embodiment, and values of other relevant parameters, based on the conditional expressions.
[ TABLE 17 ]
While the foregoing is directed to embodiments of the present invention, it will be understood by those skilled in the art that various changes may be made without departing from the spirit and scope of the invention.