Imaging Optical Lens

Abstract

The present invention relates to the field of optical lenses and discloses an imaging optical lens. [Solution] The imaging optical lens includes a total of seven lenses, which are, from the object side to the image side, a first lens having negative refractive power, a second lens having refractive power, a third lens having positive refractive power, a fourth lens having positive refractive power, a fifth lens having negative refractive power, a sixth lens having positive refractive power, and a seventh lens having negative refractive power, and the imaging optical lens satisfies the following relational expressions: 0≦(R1+R2) / (R1-R2)≦0.50, 110.00≦(FOV*f) / IH≦140.00, -1.70≦f1 / f≦-1.10, -3.00≦R5 / R6≦-0.50. The imaging optical lens provided in the present invention can meet the design requirements of large aperture, ultra-thinness, and wide angle.

Description

[Technical field]

[0001] The present invention relates to the field of optical lenses, and more particularly to imaging optical lenses applied to mobile terminal devices such as smartphones and digital cameras, and imaging devices such as monitors, PC lenses, and vehicle-mounted lenses. [Background technology]

[0002] In recent years, with the emergence of various smart devices, the demand for miniaturized imaging optical lenses is increasing, the pixel size of the photosensitive element is shrinking, and the current electronic products have high requirements for excellent functions and light, thin, and portable appearances, so that miniaturized imaging optical lenses with good imaging quality have already become mainstream in the current market. In order to obtain good imaging quality, lenses often use multiple lens structures. In addition, with the evolution of technology and the increasing diversification needs of users, the pixel area of ​​the photosensitive element is shrinking, and the requirements for the imaging quality of the system are increasing, so that a seven-lens structure is gradually appearing in the design of lenses. Therefore, there is a growing demand for wide-angle imaging lenses with excellent optical properties, small volume, and sufficient correction of aberrations. Summary of the Invention [Problem to be solved by the invention]

[0003] The present invention has been made in consideration of the above problems, and has an object to provide an imaging optical lens that has good optical performance and can satisfy the design requirements of a large aperture, an extremely thin lens, and an ultra-wide angle lens. [Means for solving the problem]

[0004] In order to achieve the above object, the technical solution of the present invention provides an imaging optical lens, which includes a total of seven lenses, which are, from the object side to the image side, in order: a first lens having negative refractive power, a second lens having refractive power, a third lens having positive refractive power, a fourth lens having positive refractive power, a fifth lens having negative refractive power, a sixth lens having positive refractive power, and a seventh lens having negative refractive power, wherein the following relational expressions are satisfied when a central radius of curvature of an object-side surface of the first lens is R1, a central radius of curvature of an image-side surface of the first lens is R2, a diagonal angle of view of the imaging optical lens is FOV, an image height of a full field of view of the imaging optical lens is IH, a focal length of the imaging optical lens is f, a focal length of the first lens is f1, a central radius of curvature of an object-side surface of the third lens is R5, and a central radius of curvature of an image-side surface of the third lens is R6: 0≦(R1+R2) / (R1-R2)≦0.50 110.00≦(FOV*f) / IH≦140.00 -1.70≦f1 / f≦-1.10 -3.00≦R5 / R6≦-0.50

[0005] Preferably, when the axial distance from the seventh lens to the image plane is BFL and the total optical length of the imaging optical lens is TTL, the following relational expression is satisfied. 0.13≦BFL / TTL≦0.22

[0006] Preferably, the fourth lens and the fifth lens are disposed so as to be bonded to each other.

[0007] Preferably, when the Abbe number of the fourth lens is v4 and the Abbe number of the fifth lens is v5, the following relational expression is satisfied. v4-v5≧35.00

[0008] Preferably, the first lens has an object-side surface formed as a concave surface paraxially, an image-side surface formed as a concave surface paraxially, and satisfies the following relational expression when the total optical length of the imaging optical lens is TTL and the axial thickness of the first lens is d1: 0.01≦d1 / TTL≦0.04

[0009] Preferably, the second lens has an object-side surface formed as a concave surface paraxially, an image-side surface formed as a convex surface paraxially, and satisfies the following relational expression when a focal length of the second lens is f2, a central radius of curvature of the object-side surface of the second lens is R3, a central radius of curvature of the image-side surface of the second lens is R4, an axial thickness of the second lens is d3, and a total optical length of the imaging optical lens is TTL: -87.96≦f2 / f≦25.91 -51.10≦(R3+R4) / (R3-R4)≦29.91 0.05≦d3 / TTL≦0.30

[0010] Preferably, the third lens has an object-side surface formed as a convex surface paraxially, an image-side surface formed as a convex surface paraxially, and satisfies the following relational expression when a focal length of the third lens is f3, an axial thickness of the third lens is d5, and a total optical length of the imaging optical lens is TTL: 0.84≦f3 / f≦3.09 -0.66≦(R5+R6) / (R5-R6)≦0.75 0.03≦d5 / TTL≦0.28

[0011] Preferably, the object-side surface of the fourth lens is formed as a convex surface paraxially, the image-side surface of the fourth lens is formed as a convex surface paraxially, and when a focal length of the fourth lens is f4, a central radius of curvature of the object-side surface of the fourth lens is R7, a central radius of curvature of the image-side surface of the fourth lens is R8, an axial thickness of the fourth lens is d7, and a total optical length of the imaging optical lens is TTL, the following relational expression is satisfied: 0.62≦f4 / f≦2.40 0.02≦(R7+R8) / (R7-R8)≦0.36 0.05≦d7 / TTL≦0.37

[0012] Preferably, the fifth lens has an object-side surface formed as a concave surface paraxially, an image-side surface formed as a concave surface paraxially, and satisfies the following relational expression when a focal length of the fifth lens is f5, a central radius of curvature of the object-side surface of the fifth lens is R9, a central radius of curvature of the image-side surface of the fifth lens is R10, an axial thickness of the fifth lens is d9, and a total optical length of the imaging optical lens is TTL: -2.61≦f5 / f≦-0.66 -0.92≦(R9+R10) / (R9-R10)≦-0.31 0≦d9 / TTL≦0.06

[0013] Preferably, the sixth lens has an object-side surface formed as a convex surface paraxially, an image-side surface formed as a convex surface paraxially, and satisfies the following relational expression when a focal length of the sixth lens is f6, a central radius of curvature of the object-side surface of the sixth lens is R11, a central radius of curvature of the image-side surface of the sixth lens is R12, an axial thickness of the sixth lens is d11, and a total optical length of the imaging optical lens is TTL: 0.51≦f6 / f≦2.55 0.02≦(R11+R12) / (R11-R12)≦1.50 0.05≦d11 / TTL≦0.24

[0014] Preferably, the seventh lens has an object-side surface formed as a convex surface paraxially, an image-side surface formed as a concave surface paraxially, and satisfies the following relational expression when a focal length of the seventh lens is f7, a central radius of curvature of the object-side surface of the seventh lens is R13, a central radius of curvature of the image-side surface of the seventh lens is R14, an axial thickness of the seventh lens is d13, and a total optical length of the imaging optical lens is TTL: -9.52≦f7 / f≦-0.88 1.42≦(R13+R14) / (R13-R14)≦14.31 0.01≦d13 / TTL≦0.07

[0015] Preferably, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens are made of glass. Effect of the Invention

[0016] The beneficial effects of the present invention are as follows: The imaging optical lens of the present invention has excellent optical performance, as well as characteristics of a large aperture, a wide angle, and an extremely thin shape, and can be applied to imaging lens components of mobile phones, web imaging lenses, and vehicle-mounted lenses, which are particularly composed of imaging elements such as high-pixel CCD and CMOS. [Brief description of the drawings]

[0017] In order to more clearly describe the technical solutions in the embodiments of the present invention, the drawings necessary for describing the embodiments are briefly described below. Obviously, the following description of the drawings is only for describing some embodiments of the present invention, and those skilled in the art can obtain other drawings from these drawings without creative efforts. [Figure 1] FIG. 1 is a diagram showing the structure of an imaging optical lens according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is a diagram showing spherical aberration of the imaging optical lens shown in FIG. [Diagram 3] FIG. 3 is a diagram showing chromatic aberration of magnification of the imaging optical lens shown in FIG. [Figure 4] FIG. 4 is a diagram showing the field curvature and distortion of the imaging optical lens shown in FIG. [Diagram 5] FIG. 5 is a diagram showing the structure of an imaging optical lens according to a second embodiment of the present invention. [Figure 6] FIG. 6 is a diagram showing the spherical aberration of the imaging optical lens shown in FIG. [Figure 7] FIG. 7 is a diagram showing chromatic aberration of magnification of the imaging optical lens shown in FIG. [Figure 8] FIG. 8 is a diagram showing the field curvature and distortion of the imaging optical lens shown in FIG. [Figure 9]FIG. 9 is a diagram showing the structure of an imaging optical lens according to a third embodiment of the present invention. [Figure 10] FIG. 10 is a diagram showing the spherical aberration of the imaging optical lens shown in FIG. [Figure 11] FIG. 11 is a diagram showing chromatic aberration of magnification of the imaging optical lens shown in FIG. [Figure 12] FIG. 12 is a diagram showing the field curvature and distortion of the imaging optical lens shown in FIG. [Figure 13] FIG. 13 is a diagram showing the structure of an imaging optical lens according to a fourth embodiment of the present invention. [Figure 14] FIG. 14 is a diagram showing the spherical aberration of the imaging optical lens shown in FIG. [Figure 15] FIG. 15 is a diagram showing chromatic aberration of magnification of the imaging optical lens shown in FIG. [Figure 16] FIG. 16 is a diagram showing the field curvature and distortion of the imaging optical lens shown in FIG. [Figure 17] FIG. 17 is a diagram showing the structure of an imaging optical lens according to a fifth embodiment of the present invention. [Figure 18] FIG. 18 is a diagram showing the spherical aberration of the imaging optical lens shown in FIG. [Figure 19] FIG. 19 is a diagram showing chromatic aberration of magnification of the imaging optical lens shown in FIG. [Figure 20] FIG. 20 is a diagram showing the field curvature and distortion of the imaging optical lens shown in FIG. [Figure 21] FIG. 21 is a diagram showing the structure of an imaging optical lens according to a comparative embodiment. [Figure 22] FIG. 22 is a diagram showing the spherical aberration of the imaging optical lens shown in FIG. [Figure 23] FIG. 23 is a diagram showing chromatic aberration of magnification of the imaging optical lens shown in FIG. [Figure 24] FIG. 24 is a diagram showing the field curvature and distortion of the imaging optical lens shown in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] In order to clarify the objectives, technical solutions and advantages of the present invention, the following detailed description of the embodiments of the present invention will be given with reference to the drawings. However, in the embodiments of the present invention, many technical details are described to allow those skilled in the art to better understand the present invention, but it is obvious to those skilled in the art that the technical solutions protected by the present invention can be realized without these technical details and various changes and modifications based on the following embodiments.

[0019] Referring to the drawings, the technical solution of the present invention provides imaging optical lenses 10, 20, 30, 40, 50. Figures 1, 5, 9, 13, 17 show the imaging optical lenses 10, 20, 30, 40, 50 of the present invention, which include a total of seven lenses. Specifically, the imaging optical lens includes, in order from the object side to the image side, a first lens L1, a second lens L2, an aperture S1, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, and a seventh lens L7. An optical element such as an optical filter GF may be provided between the seventh lens L7 and the image surface Si.

[0020] The first lens L1 is made of glass, the second lens L2 is made of glass, the third lens L3 is made of glass, the fourth lens L4 is made of glass, the fifth lens L5 is made of glass, the sixth lens L6 is made of glass, and the seventh lens L7 is made of glass. Each lens may be made of other materials.

[0021] The object-side surfaces and image-side surfaces of the second lens L2, the third lens L3, the fourth lens L4, and the fifth lens L5 are all spherical, and the object-side surfaces and image-side surfaces of the first lens L1, the sixth lens L6, and the seventh lens L7 are all aspheric.

[0022] When the central radius of curvature of the object side surface of the first lens L1 is R1 and the central radius of curvature of the image side surface of the first lens L1 is R2, the relational expression 0≦(R1+R2) / (R1-R2)≦0.50 is established, and the shape of the first lens L1 is regulated. If it is within the range of this relational expression, the degree of deviation of the light beam passing through the lens can be mitigated, and aberration can be effectively reduced.

[0023] When the diagonal angle of view of the imaging optical lens is FOV, the focal length of the imaging optical lens is f, and the image height of the entire field of view of the imaging optical lens is IH, the relational expression 110.00≦(FOV*f) / IH≦140.00 has been established. Within the range of this relational expression, a large angle of view and a long focal length can be achieved at the same time, and imaging at medium to long distances can be realized.

[0024] When the focal length of the first lens L1 is f1, the relational expression of -1.70≦f1 / f≦-1.10 is established. This relational expression specifies the ratio of the focal length of the first lens L1 to the imaging optical lens. By reasonably allocating the optical focal length of the imaging optical lens, the field curvature amount of the system can be effectively balanced, and the field curvature offset amount of the central field can be less than 0.02 mm.

[0025] When the central radius of curvature of the object side surface of the third lens L3 is R5 and the central radius of curvature of the image side surface of the third lens L3 is R6, the relational expression -3.00≦R5 / R6≦-0.50 is established, and this relational expression specifies the shape of the third lens L3. If it is within the range of this relational expression, the degree of deviation of the light beam passing through the lens can be mitigated, and the aberration can be effectively reduced.

[0026] When the above-mentioned relational expressions are satisfied, the imaging optical lenses 10, 20, 30, 40, 50 have good optical performance and can meet the design requirements of large aperture, wide angle, and ultra-thinness. According to the characteristics of the imaging optical lenses 10, 20, 30, 40, 50, the imaging optical lenses 10, 20, 30, 40, 50 can be applied to imaging lens parts of mobile phones, web imaging lenses, and vehicle-mounted lenses, which are particularly composed of imaging elements such as CCD and CMOS for high pixels.

[0027] Based on the above relationships and feasible functions, the characteristics of each lens are further refined as follows:

[0028] When the axial distance from the seventh lens L7 to the image plane is BFL and the optical total length of the imaging optical lens is TTL, the following relational expression is established: 0.13≦BFL / TTL≦0.22, which specifies the ratio between the back focus and the optical total length of the imaging optical lens. In addition to achieving compactness, the back focus is long, which is advantageous for module assembly, the total length is short, and the structure is compact, and the sensitivity to the MTF of the lens is reduced, which increases the production yield and reduces the production cost.

[0029] The fourth lens L4 and the fifth lens L5 are installed so as to be bonded together. By installing them so as to be bonded together, the overall volume of the imaging optical lens can be reduced, and by installing them so as to be bonded together, the two lenses are integrated into one overall structure, and when assembling the optical module, the installation of the two lenses can be completed with only one placement.

[0030] When the Abbe number of the fourth lens L4 is v4 and the Abbe number of the fifth lens L5 is v5, the relational expression v4-v5≧35.00 is established, which specifies the difference in the Abbe numbers of the cemented lenses. Within the range of this relational expression, the material attributes can be effectively assigned, the chromatic aberration can be effectively corrected, and the chromatic aberration |LC|≦6.0 μm.

[0031] The first lens L1 has a surface on the object side that is concave paraxially, a surface on the image side that is concave paraxially, and has negative refractive power. The surface on the object side and the surface on the image side of the first lens L1 may have other concave and convex distribution forms.

[0032] When the axial thickness of the first lens L1 is d1, the relational expression 0.01≦d1 / TTL≦0.04 is established, and being within the range of this relational expression is advantageous for realizing an extremely thin lens. Also, it is preferable that 0.01≦d1 / TTL≦0.03.

[0033] The second lens L2 has a surface on the object side that is concave on the paraxial direction, a surface on the image side that is convex on the paraxial direction, and has a positive or negative refractive power. The surface on the object side and the surface on the image side of the second lens L2 may have other concave or convex distribution forms.

[0034] When the focal length of the second lens L2 is f2, the relational expression of -87.96≦f2 / f≦25.91 is established. By controlling the refractive power of the second lens L2 within a reasonable range, it is advantageous to correct the aberration of the optical system. In addition, it is preferable that -54.97≦f2 / f≦20.73.

[0035] When the central radius of curvature of the object side surface of the second lens L2 is R3 and the central radius of curvature of the image side surface of the second lens L2 is R4, the relational expression of -51.10≦(R3+R4) / (R3-R4)≦29.91 is established, and the shape of the second lens L2 can be reasonably controlled so that the second lens L2 can effectively correct the chromatic aberration of the system. It is also preferable that -31.94≦(R3+R4) / (R3-R4)≦23.93.

[0036] When the axial thickness of the second lens L2 is d3, the relational expression 0.05≦d3 / TTL≦0.30 is established. If it is within the range of this relational expression, it is advantageous for realizing an extremely thin lens. In addition, it is preferable that 0.09≦d3 / TTL≦0.24.

[0037] The third lens L3 has a positive refractive power, the object side surface of which is convex on the paraxial direction, and the image side surface of which is convex on the paraxial direction. The object side surface and the image side surface of the third lens L3 may have other concave and convex distribution forms.

[0038] When the focal length of the third lens L3 is f3, the relational expression 0.84≦f3 / f≦3.09 is established. By appropriately allocating the refractive power, the system has excellent imaging quality and low sensitivity. In addition, it is preferable that 1.34≦f3 / f≦2.47.

[0039] When the central radius of curvature of the object side surface of the third lens L3 is R5 and the central radius of curvature of the image side surface of the third lens L3 is R6, the relational expression -0.66≦(R5+R6) / (R5-R6)≦0.75 is established. This relational expression specifies the shape of the third lens L3. As lenses become thinner and wider in angle, this is advantageous for correcting problems such as aberrations at off-axis angles of view. It is also preferable that -0.41≦(R5+R6) / (R5-R6)≦0.60.

[0040] When the axial thickness of the third lens L3 is d5, the relational expression 0.03≦d5 / TTL≦0.28 is established. If it is within the range of this relational expression, it is advantageous for realizing an extremely thin lens. In addition, it is preferable that 0.04≦d5 / TTL≦0.22.

[0041] The fourth lens L4 has a positive refractive power, its object side surface is formed as a paraxial convex surface, its image side surface is formed as a paraxial convex surface, and the object side surface and the image side surface of the fourth lens L4 may have other concave and convex distribution forms.

[0042] When the focal length of the fourth lens L4 is f4, the relational expression 0.62≦f4 / f≦2.40 is established. By appropriately allocating the refractive power, the system has excellent imaging quality and low sensitivity. In addition, it is preferable that 1.00≦f4 / f≦1.92.

[0043] When the central radius of curvature of the object side surface of the fourth lens L4 is R7 and the central radius of curvature of the image side surface of the fourth lens L4 is R8, the relational expression 0.02≦(R7+R8) / (R7-R8)≦0.36 is established. This relational expression specifies the shape of the fourth lens L4. If it is within the range of this relational expression, it helps to make the transition of light gentler and improves the image quality. In addition, it is preferable that 0.03≦(R7+R8) / (R7-R8)≦0.29.

[0044] When the axial thickness of the fourth lens L4 is d7, the relational expression 0.05≦d7 / TTL≦0.37 is established. If the relational expression is within the range, it is advantageous for realizing a very thin lens. In addition, it is preferable that 0.07≦d7 / TTL≦0.29.

[0045] The fifth lens L5 has a paraxially concave object side surface and a paraxially concave image side surface, and has negative refractive power. The object side surface and the image side surface of the fifth lens L5 may have other concave and convex distribution forms.

[0046] When the focal length of the fifth lens L5 is f5, the relational expression of -2.61≦f5 / f≦-0.66 is established. By limiting the fifth lens L5, the light ray angle of the imaging optical lens 10 can be made gentler, and the tolerance sensitivity can be reduced. In addition, it is preferable that -1.63≦f5 / f≦-0.83.

[0047] When the central radius of curvature of the object side surface of the fifth lens L5 is R9 and the central radius of curvature of the image side surface of the fifth lens L5 is R10, the relational expression of -0.92≦(R9+R10) / (R9-R10)≦-0.31 is established, and the shape of the fifth lens L5 is specified. If it is within the range of this relational expression, it is advantageous for correcting astigmatism and distortion of the imaging optical lens. In addition, it is preferable that -0.58≦(R9+R10) / (R9-R10)≦-0.38.

[0048] When the axial thickness of the fifth lens L5 is d9, the relational expression 0≦d9 / TTL≦0.06 is established. If the relational expression is within the range, it is advantageous for realizing a very thin lens. In addition, it is preferable that 0≦d9 / TTL≦0.05.

[0049] The sixth lens L6 has a positive refractive power, its object side surface is formed as a paraxial convex surface, its image side surface is formed as a paraxial convex surface, and the object side surface and the image side surface of the sixth lens L6 may have other concave and convex distribution forms.

[0050] When the focal length of the imaging optical lens is f and the focal length of the sixth lens L6 is f6, the relational expression of 0.51≦f6 / f≦2.55 is established, and by appropriately allocating the refractive power, the system has excellent imaging quality and low sensitivity. It is also preferable that 0.81≦f6 / f≦2.04.

[0051] When the radius of curvature of the center of the surface of the sixth lens L6 on the object side is R11 and the radius of curvature of the center of the surface of the sixth lens L6 on the image side is R12, the relational expression of 0.02≦(R11+R12) / (R11-R12)≦1.50 is established, and the shape of the sixth lens L6 is regulated. If it is within the range of this relational expression, it is advantageous for correcting problems such as aberrations of the off-axis angle of view as the lens becomes extremely thin and the angle of view becomes wider. In addition, it is preferable that 0.03≦(R11+R12) / (R11-R12)≦1.20.

[0052] When the axial thickness of the sixth lens L6 is d11, the relational expression 0.05≦d11 / TTL≦0.24 is established. If the relational expression is within the range, it is advantageous for realizing a very thin lens. In addition, it is preferable that 0.08≦d11 / TTL≦0.19.

[0053] The seventh lens L7 has a negative refractive power, its object side surface is convex on the paraxial direction, and its image side surface is concave on the paraxial direction. The object side surface and the image side surface of the seventh lens L7 may have other concave and convex distribution forms.

[0054] When the focal length of the seventh lens L7 is f7, the relational expression of -9.52≦f7 / f≦-0.88 is established, which specifies the ratio between the focal length of the last lens and the total focal length of the imaging optical lens. The refractive power of the system can be reasonably distributed to contribute to light collection and ensure the light exchange rate. It is also preferable that -5.95≦f7 / f≦-1.10.

[0055] When the radius of curvature of the center of the surface of the seventh lens L7 on the object side is R13 and the radius of curvature of the center of the surface of the seventh lens L7 on the image side is R14, the relational expression of 1.42≦(R13+R14) / (R13-R14)≦14.31 is established, and the shape of the seventh lens L7 is regulated. If it is within the range of this relational expression, it is advantageous for correcting problems such as aberrations of the off-axis angle of view as the lens becomes extremely thin and wide-angle. In addition, it is preferable that 2.27≦(R13+R14) / (R13-R14)≦11.45.

[0056] When the axial thickness of the seventh lens L7 is d13, the relational expression 0.01≦d13 / TTL≦0.07 is established. If the relational expression is within the range, it is advantageous for realizing a very thin lens. In addition, it is preferable that 0.01≦d13 / TTL≦0.06.

[0057] The imaging optical lens further satisfies the relation TTL / IH≦6.49, which is advantageous for achieving a very thin lens. It is also preferable that TTL / IH≦6.31.

[0058] The field of view FOV of the above imaging optical lens is 98.88° or more, which allows for a wide angle of view.

[0059] The aperture value FNO of the above imaging optical lens is 1.65 or less, which realizes a large aperture and provides excellent imaging performance of the imaging optical lens.

[0060] The imaging optical lens according to the present invention will be described below using examples. The symbols used in each example are as follows. The units of the focal length, axial distance, central radius of curvature, axial thickness, inflection point position, and stationary point position are mm.

[0061] TTL: total optical length (the axial distance from the object-side surface of the first lens L1 to the image plane Si), in mm.

[0062] Aperture No. FNO: The ratio of the effective focal length of an imaging optical lens to the entrance pupil diameter.

[0063] The technical solution of the present invention will be described in detail below using five embodiments, and comparative embodiments are provided for reference. If the above relationship range is exceeded, the technical effect of the present invention cannot be achieved. (First embodiment)

[0064] Tables 1 and 2 show setting data of the imaging optical lens 10 according to the first embodiment of the present invention.

[0065] [Table 1]

[0066] Here, the meanings of the symbols are as follows: S1: Aperture R: Radius of curvature at the center of the optical surface R1: Radius of curvature of the center of the object side surface of the first lens L1 R2: Radius of central curvature of the image-side surface of the first lens L1 R3: Radius of curvature of the center of the object side surface of the second lens L2 R4: Radius of central curvature of the image-side surface of the second lens L2 R5: Radius of curvature of the center of the object side surface of the third lens L3 R6: Radius of central curvature of the image-side surface of the third lens L3 R7: Radius of curvature of the center of the object side surface of the fourth lens L4 R8: Radius of central curvature of the image-side surface of the fourth lens L4 R9: Radius of curvature of the center of the object side surface of the fifth lens L5 R10: Radius of central curvature of the image-side surface of the fifth lens L5 R11: Radius of curvature of the center of the object side surface of the sixth lens L6 R12: Radius of central curvature of the image-side surface of the sixth lens L6 R13: Radius of curvature of the center of the object side surface of the seventh lens L7 R14: The central curvature radius of the image-side surface of the seventh lens L7 R15: Radius of curvature of the center of the object-side surface of the optical filter GF R16: Radius of central curvature of the image-side surface of the optical filter GF d: Axial thickness of lens, axial distance between lenses d0: The axial distance from the aperture stop S1 to the object side surface of the first lens L1 d1: Axial thickness of the first lens L1 d2: The axial distance from the image-side surface of the first lens L1 to the object-side surface of the second lens L2 d3: Axial thickness of the second lens L2 d4: The axial distance from the image-side surface of the second lens L2 to the object-side surface of the third lens L3 d5: Axial thickness of the third lens L3 d6: The axial distance from the image-side surface of the third lens L3 to the object-side surface of the fourth lens L4 d7: Axial thickness of the fourth lens L4 d8: The axial distance from the image-side surface of the fourth lens L4 to the object-side surface of the fifth lens L5 d9: Axial thickness of the fifth lens L5 d10: The axial distance from the image-side surface of the fifth lens L5 to the object-side surface of the sixth lens L6 d11: Axial thickness of the sixth lens L6 d12: The axial distance from the image-side surface of the sixth lens L6 to the object-side surface of the seventh lens L7 d13: Axial thickness of the seventh lens L7 d14: The axial distance from the image-side surface of the seventh lens L7 to the object-side surface of the optical filter GF d15: Axial thickness of optical filter GF d16: The axial distance from the image-side surface of the optical filter GF to the image plane Si nd: Refractive index of d line (d line is green light with a wavelength of 550 nm) nd1: Refractive index of the first lens L1 at the d line nd2: Refractive index of the d line of the second lens L2 nd3: Refractive index of the d line of the third lens L3 nd4: Refractive index of the d line of the fourth lens L4 nd5: Refractive index of the d line of the fifth lens L5 nd6: Refractive index of the d line of the sixth lens L6 nd7: Refractive index of the d line of the seventh lens L7 ndg: Refractive index of the d line of the optical filter GF vd: Abbe number v1: Abbe number of the first lens L1 v2: Abbe number of the second lens L2 v3: Abbe number of the third lens L3 v4: Abbe number of the fourth lens L4 v5: Abbe number of the fifth lens L5 v6: Abbe number of the sixth lens L6 v7: Abbe number of the seventh lens L7 vg: Abbe number of the optical filter GF

[0067] Table 2 shows data on the aspheric surfaces of each lens in the imaging optical lens 10 according to the first embodiment of the present invention.

[0068] [Table 2]

[0069] For convenience, the aspheric surface of each lens surface is expressed by the following formula (1), but the present invention is not limited to the aspheric polynomial of this formula (1). z=(cr 2 ) / {1+[1-(k+1)(c 2 r 2 )] 1 / 2}+A4r 4 +A6r 6 +A8r 8 +A10r 10 +A12r 12 +A14r 14 +A16r 1 (1)

[0070] where k is the conic coefficient, A4, A6, A8, A10, A12, A14, and A16 are aspheric coefficients, c is the central curvature of the optical surface, r is the perpendicular distance between a point on the aspheric curve and the optical axis, and z is the aspheric depth (the perpendicular distance between a point on the aspheric surface that is a distance r away from the optical axis and the tangent plane that is tangent to the vertex on the aspheric optical axis).

[0071] Fig. 2 and Fig. 3 are diagrams showing spherical aberration and lateral chromatic aberration of light with wavelengths of 650 nm, 610 nm, 555 nm, 510 nm, and 470 nm, respectively, after passing through the imaging optical lens 10 according to the first embodiment. Fig. 4 is a diagram showing field curvature and distortion aberration of light with wavelength of 555 nm after passing through the imaging optical lens 10 according to the first embodiment, where the field curvature S in Fig. 4 is the field curvature in the sagittal direction and T is the field curvature in the meridional direction.

[0072] In this embodiment, the imaging optical lens 10 has an entrance pupil diameter ENPD of 3.788 mm, an image height IH of the entire field of view of 5.139 mm, and a diagonal angle of view FOV of 101.69°. The imaging optical lens 10 can satisfy the design requirements of a large aperture, a wide angle, and an extremely thin design, and has excellent optical characteristics with its on-axis and off-axis chromatic aberrations sufficiently corrected. Second embodiment

[0073] In the second embodiment, the meanings of the symbols are the same as in the first embodiment.

[0074] 5 shows an imaging optical lens 20 according to a second embodiment of the present invention. The second lens L2 has a positive refractive power.

[0075] Tables 3 and 4 show setting data of the imaging optical lens 20 according to the second embodiment of the present invention.

[0076] [Table 3]

[0077] Table 4 shows data on the aspheric surfaces of each lens in the imaging optical lens 20 according to the second embodiment of the present invention.

[0078] [Table 4]

[0079] Fig. 5 and Fig. 6 are diagrams showing spherical aberration and lateral chromatic aberration of light having wavelengths of 650 nm, 610 nm, 555 nm, 510 nm, and 470 nm, respectively, after passing through the imaging optical lens 20 according to the second embodiment. Fig. 8 is a diagram showing field curvature and distortion aberration of light having a wavelength of 555 nm after passing through the imaging optical lens 20 according to the second embodiment. The field curvature S in Fig. 8 is the field curvature in the sagittal direction, and T is the field curvature in the meridional direction.

[0080] In this embodiment, the imaging optical lens 20 has an entrance pupil diameter ENPD of 3.786 mm, an image height IH of the entire field of view of 5.210 mm, and a diagonal angle of view FOV of 108.21°. The imaging optical lens 20 can satisfy the design requirements of a large aperture, a wide angle, and an extremely thin design, and has excellent optical characteristics with its on-axis and off-axis chromatic aberrations sufficiently corrected. Third embodiment

[0081] In the third embodiment, the meanings of the symbols are the same as in the first embodiment.

[0082] Shown in FIG. 9 is an imaging optical lens 30 according to a third embodiment of the present invention.

[0083] Tables 5 and 6 show setting data of the imaging optical lens 30 according to the third embodiment of the present invention.

[0084] [Table 5]

[0085] Table 6 shows data on the aspheric surfaces of each lens in the imaging optical lens 30 according to the third embodiment of the present invention.

[0086] [Table 6]

[0087] Fig. 10 and Fig. 11 are diagrams showing spherical aberration and lateral chromatic aberration of light with wavelengths of 650 nm, 610 nm, 555 nm, 510 nm, and 470 nm, respectively, after passing through the imaging optical lens 30 according to the third embodiment. Fig. 12 is a diagram showing field curvature and distortion aberration of light with wavelength of 555 nm after passing through the imaging optical lens 30 according to the third embodiment. The field curvature S in Fig. 12 is the field curvature in the sagittal direction, and T is the field curvature in the meridional direction.

[0088] In this embodiment, the entrance pupil diameter ENPD of the imaging optical lens 30 is 4.255 mm, the image height IH of the entire field of view is 4.950 mm, and the diagonal angle of view FOV is 98.88°. The imaging optical lens 30 can satisfy the design requirements of a large aperture, a wide angle, and an extremely thin design, and has excellent optical characteristics with its on-axis and off-axis chromatic aberrations sufficiently corrected. (Fourth embodiment)

[0089] In the fourth embodiment, the meanings of the symbols are the same as in the first embodiment.

[0090] 13 shows an imaging optical lens 40 according to a fourth embodiment of the present invention. The second lens L2 has a positive refractive power.

[0091] Tables 7 and 8 show setting data for the imaging optical lens 40 according to the fourth embodiment of the present invention.

[0092] [Table 7]

[0093] Table 8 shows data on the aspheric surfaces of each lens in the imaging optical lens 40 according to the fourth embodiment of the present invention.

[0094] [Table 8]

[0095] Fig. 14 and Fig. 15 are diagrams showing spherical aberration and lateral chromatic aberration of light having wavelengths of 650 nm, 610 nm, 555 nm, 510 nm, and 470 nm, respectively, after passing through the imaging optical lens 40 according to the fourth embodiment. Fig. 16 is a diagram showing field curvature and distortion aberration of light having a wavelength of 555 nm after passing through the imaging optical lens 40 according to the fourth embodiment. The field curvature S in Fig. 16 is the field curvature in the sagittal direction, and T is the field curvature in the meridional direction.

[0096] In this embodiment, the imaging optical lens 40 has an entrance pupil diameter ENPD of 3.236 mm, an image height IH of the entire field of view of 5.390 mm, and a diagonal angle of view FOV of 111.74°. The imaging optical lens 40 can satisfy the design requirements of a large aperture, a wide angle, and an extremely thin design, and has excellent optical characteristics with its on-axis and off-axis chromatic aberrations sufficiently corrected. Fifth embodiment

[0097] In the fifth embodiment, the meanings of the symbols are the same as in the first embodiment.

[0098] 17 shows an imaging optical lens 50 according to a fifth embodiment of the present invention. The second lens L2 has a positive refractive power.

[0099] Tables 9 and 10 show setting data for the imaging optical lens 50 according to the fifth embodiment of the present invention.

[0100] [Table 9]

[0101] Table 10 shows data on the aspheric surfaces of each lens in the imaging optical lens 50 according to the fifth embodiment of the present invention.

[0102] [Table 10]

[0103] Fig. 18 and Fig. 19 are diagrams showing spherical aberration and lateral chromatic aberration of light having wavelengths of 650 nm, 610 nm, 555 nm, 510 nm, and 470 nm, respectively, after passing through the imaging optical lens 50 according to the fifth embodiment. Fig. 20 is a diagram showing field curvature and distortion aberration of light having a wavelength of 555 nm after passing through the imaging optical lens 50 according to the fifth embodiment. The field curvature S in Fig. 16 is the field curvature in the sagittal direction, and T is the field curvature in the meridional direction.

[0104] In this embodiment, the imaging optical lens 40 has an entrance pupil diameter ENPD of 3.448 mm, an image height IH of the entire field of view of 5.110 mm, and a diagonal angle of view FOV of 112.26°. The imaging optical lens 50 can satisfy the design requirements of a large aperture, a wide angle, and an extremely thin design, and has excellent optical characteristics with its on-axis and off-axis chromatic aberrations sufficiently corrected.

[0105] Table 13 below shows the values ​​of the first, second, third, fourth and fifth embodiments and values ​​corresponding to the parameters defined by the relational expressions. (Comparative embodiment)

[0106] In the comparative embodiment, the symbols have the same meanings as in the first embodiment.

[0107] Shown in FIG. 21 is an imaging optical lens 60 according to a comparative embodiment.

[0108] Tables 11 and 12 show setting data for the imaging optical lens 60 according to the comparative embodiment.

[0109] [Table 11]

[0110] Table 12 shows data on the aspheric surfaces of each lens in the imaging optical lens 60 according to the comparative embodiment.

[0111] [Table 12]

[0112] Fig. 22 and Fig. 23 are diagrams showing spherical aberration and lateral chromatic aberration of light having wavelengths of 650 nm, 610 nm, 555 nm, 510 nm, and 470 nm, respectively, after passing through the imaging optical lens 60 according to the comparative embodiment. Fig. 24 is a diagram showing field curvature and distortion aberration of light having a wavelength of 555 nm after passing through the imaging optical lens 60 according to the comparative embodiment. The field curvature S in Fig. 24 is the field curvature in the sagittal direction, and T is the field curvature in the meridional direction.

[0113] The numerical values ​​corresponding to each of the above-mentioned relational expressions in the comparative embodiment are shown in Table 13 below. Apparently, the imaging optical lens 60 of the comparative embodiment does not satisfy the above-mentioned relational expression -1.70≦f1 / f≦-1.10, and has poor imaging performance.

[0114] In the comparative embodiment, the entrance pupil diameter ENPD of the imaging optical lens 60 is 3.625 mm, the image height IH of the entire field of view is 4.840 mm, and the diagonal angle of view FOV is 101.70°. The imaging optical lens 60 does not satisfy the design requirements of a large aperture, a wide angle, and an extremely thin design.

[0115] [Table 13]

[0116] Although the above-mentioned embodiments are specific embodiments for realizing the present invention, it should be understood by those skilled in the art that in practical application, various changes in form and details that do not deviate from the spirit and scope of the present invention are all within the scope of protection of the present invention.

Claims

1. An imaging optical lens including a total of seven lenses, the seven lenses being, in order from the object side to the image side, a first lens having negative refractive power, a second lens having refractive power, a third lens having positive refractive power, a fourth lens having positive refractive power, a fifth lens having negative refractive power, a sixth lens having positive refractive power, and a seventh lens having negative refractive power, Here, when a central radius of curvature of the object-side surface of the first lens is R1, a central radius of curvature of the image-side surface of the first lens is R2, a diagonal angle of view of the imaging optical lens is FOV, an image height of a full field of view of the imaging optical lens is IH, a focal length of the imaging optical lens is f, a focal length of the first lens is f1, a central radius of curvature of the object-side surface of the third lens is R5, and a central radius of curvature of the image-side surface of the third lens is R6, the imaging optical lens is characterized in that the following relational expression is satisfied: 0≦(R1+R2) / (R1-R2)≦0.50 110.00≦(FOV*f) / IH≦140.00 −1.70≦f1 / f≦−1.10 −3.00≦R5 / R6≦−0.50

2. 2. The imaging optical lens according to claim 1, wherein the following relational expression is satisfied when an axial distance from the seventh lens to an image plane is BFL and a total optical length of the imaging optical lens is TTL: 0.13≦BFL / TTL≦0.22

3. The imaging optical lens according to claim 1 , wherein the fourth lens and the fifth lens are disposed so as to be bonded to each other.

4. 4. The imaging optical lens according to claim 3, wherein when the Abbe number of the fourth lens is v4 and the Abbe number of the fifth lens is v5, the following relational expression is satisfied: v4-v5≧35.00

5. the first lens has an object-side surface formed as a paraxial concave surface, and an image-side surface formed as a paraxial concave surface, 2. The imaging optical lens according to claim 1, wherein the following relational expression is satisfied when the total optical length of the imaging optical lens is TTL and the axial thickness of the first lens is d1: 0.01≦d1 / TTL≦0.04

6. the second lens has an object-side surface formed as a concave surface on a paraxial line and an image-side surface formed as a convex surface on a paraxial line, 2. The imaging optical lens according to claim 1, wherein the following relational expression is satisfied when a focal length of the second lens is f2, a central radius of curvature of an object-side surface of the second lens is R3, a central radius of curvature of an image-side surface of the second lens is R4, an axial thickness of the second lens is d3, and a total optical length of the imaging optical lens is TTL: −87.96≦f2 / f≦25.91 -51.10≦(R3+R4) / (R3-R4)≦29.91 0.05≦d3 / TTL≦0.30

7. the third lens has an object-side surface formed as a convex surface on a paraxial line, and an image-side surface formed as a convex surface on a paraxial line, 2. The imaging optical lens according to claim 1, wherein the following relational expression is satisfied when a focal length of the third lens is f3, an axial thickness of the third lens is d5, and a total optical length of the imaging optical lens is TTL: 0.84≦f3 / f≦3.09 -0.66≦(R5+R6) / (R5-R6)≦0.75 0.03≦d5 / TTL≦0.28

8. the fourth lens has an object-side surface formed as a convex surface on a paraxial line, and an image-side surface formed as a convex surface on a paraxial line, 2. The imaging optical lens according to claim 1, wherein the following relational expression is satisfied when a focal length of the fourth lens is f4, a central radius of curvature of an object-side surface of the fourth lens is R7, a central radius of curvature of an image-side surface of the fourth lens is R8, an axial thickness of the fourth lens is d7, and a total optical length of the imaging optical lens is TTL: 0.62≦f4 / f≦2.40 0.02≦(R7+R8) / (R7-R8)≦0.36 0.05≦d7 / TTL≦0.37

9. the fifth lens has an object-side surface formed as a paraxial concave surface, and an image-side surface formed as a paraxial concave surface, 2. The imaging optical lens according to claim 1, wherein the following relational expression is satisfied when a focal length of the fifth lens is f5, a central radius of curvature of an object-side surface of the fifth lens is R9, a central radius of curvature of an image-side surface of the fifth lens is R10, an axial thickness of the fifth lens is d9, and a total optical length of the imaging optical lens is TTL: −2.61≦f5 / f≦−0.66 -0.92≦(R9+R10) / (R9-R10)≦-0.31 0≦d9 / TTL≦0.06

10. the sixth lens has an object-side surface formed as a convex surface on a paraxial line, and an image-side surface formed as a convex surface on a paraxial line, 2. The imaging optical lens according to claim 1, wherein the following relational expression is satisfied when a focal length of the sixth lens is f6, a central radius of curvature of an object-side surface of the sixth lens is R11, a central radius of curvature of an image-side surface of the sixth lens is R12, an axial thickness of the sixth lens is d11, and a total optical length of the imaging optical lens is TTL: 0.51≦f6 / f≦2.55 0.02≦(R11+R12) / (R11-R12)≦1.50 0.05≦d11 / TTL≦0.24

11. the seventh lens has an object-side surface formed as a convex surface on a paraxial line, and an image-side surface formed as a concave surface on a paraxial line, 2. The imaging optical lens according to claim 1, wherein the following relational expression is satisfied when a focal length of the seventh lens is f7, a central radius of curvature of an object-side surface of the seventh lens is R13, a central radius of curvature of an image-side surface of the seventh lens is R14, an axial thickness of the seventh lens is d13, and a total optical length of the imaging optical lens is TTL: −9.52≦f7 / f≦−0.88 1.42≦(R13+R14) / (R13-R14)≦14.31 0.01≦d13 / TTL≦0.07

12. 2. The imaging optical lens according to claim 1, wherein the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens are made of glass.

Images