CN111751962B - A small optical imaging lens with large light transmission - Google Patents

Abstract

The invention relates to the technical field of lenses. The invention discloses a small-sized large-light-transmission optical imaging lens, which sequentially comprises a first lens, a second lens and a third lens from an object side to an image side along an optical axis; the first lens, the second lens and the sixth lens are all convex-concave lenses with negative refractive index, the third lens has positive refractive index, and the object side surface is a convex surface; the fourth lens is a concave-convex lens with positive refractive power, the fifth lens is a convex-convex lens with positive refractive power, and both the object side surface and the image side surface of the third lens are aspheric surfaces or both the object side surface and the image side surface of the fourth lens are aspheric surfaces. The invention has the advantages of high resolution, small distortion, good imaging quality, large relative aperture, uniform relative illumination and miniaturization.

Description

A small optical imaging lens with large light transmission

Technical Field

The invention belongs to the technical field of lenses, and in particular relates to a small optical imaging lens with large light transmission.

Background Art

With the continuous advancement of science and technology and the continuous development of society, optical imaging lenses have also developed rapidly in recent years. Optical imaging lenses are widely used in various fields such as smart phones, tablets, video conferencing, vehicle monitoring, security monitoring, 3D scanning, etc. Therefore, the requirements for optical imaging lenses are also increasing.

In systems that use TOF (time of flight) technology for 3D scanning, the performance of the TOF lens is critical and will greatly affect the effect and reliability of 3D scanning. However, the TOF lenses currently on the market still have many shortcomings, such as small relative aperture, which does not meet the ideal relative aperture required by the application; large overall size and long total length, which cannot meet the needs of miniaturization; poor distortion control, and correction of distortion leads to a large number of pixel losses; in order to achieve a large relative aperture, the relative illumination of the edge field of view is sacrificed greatly; the transfer function is not well controlled, the resolution is low, and the imaging quality is poor, etc., which can no longer meet the increasingly high requirements in the field of 3D scanning and are in urgent need of improvement.

Summary of the invention

The purpose of the present invention is to provide a small optical imaging lens with large light transmission to solve the above-mentioned technical problems.

To achieve the above object, the technical solution adopted by the present invention is: a small optical imaging lens with large light transmission, which includes a first lens to a sixth lens in sequence along an optical axis from the object side to the image side; the first lens to the sixth lens each include an object side surface facing the object side and allowing imaging light to pass through, and an image side surface facing the image side and allowing imaging light to pass through;

The first lens has a negative refractive power, the object side surface of the first lens is a convex surface, and the image side surface of the first lens is a concave surface;

The second lens has a negative refractive power, the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a concave surface;

The third lens has a positive refractive power, and the object side surface of the third lens is a convex surface;

The fourth lens element has a positive refractive power, the object side surface of the fourth lens element is a concave surface, and the image side surface of the fourth lens element is a convex surface;

The fifth lens element has a positive refractive power, the object side surface of the fifth lens element is a convex surface, and the image side surface of the fifth lens element is a convex surface;

The sixth lens element has a negative refractive power, the object side surface of the sixth lens element is a convex surface, and the image side surface of the sixth lens element is a concave surface;

The object side surface and the image side surface of the third lens are both aspherical surfaces or the object side surface and the image side surface of the fourth lens are both aspherical surfaces;

The optical imaging lens has only the first to sixth lenses with refractive power.

Furthermore, it also includes an aperture, which is arranged between the third lens and the fourth lens.

Furthermore, the optical imaging lens also satisfies: nd3≥1.85, where nd3 is the refractive index of the third lens.

Furthermore, the optical imaging lens also satisfies: 2.7<|f1/f|<3.8 and 2.7<|f2/f|<3.8, wherein f1 is the focal length of the first lens, f2 is the focal length of the second lens, and f is the focal length of the optical imaging lens.

Furthermore, the optical imaging lens also satisfies: vd2≥38, where vd2 is the dispersion coefficient of the second lens.

Furthermore, the optical imaging lens also satisfies: nd5>1.8, where nd5 is the refractive index of the fifth lens.

Furthermore, the optical imaging lens also satisfies: 1.51≤nd1≤nd2, 1.68≤nd4≤nd3≤2.1 and 1.49≤nd6≤nd5≤2.1, wherein nd1, nd2, nd3, nd4, nd5 and nd6 are the refractive indices of the first lens, the second lens, the third lens, the fourth lens, the fifth lens and the sixth lens respectively.

Furthermore, the optical imaging lens also satisfies: |Φ3|≤0.16mm ^-1 , |Φ4|≤0.21mm ^-1 , |Φ5|≤0.2mm ^-1 , |Φ6|≤0.15mm ^-1 , wherein Φ3 is the focal power of the third lens, Φ4 is the focal power of the fourth lens, Φ5 is the focal power of the fifth lens, and Φ6 is the focal power of the sixth lens.

Furthermore, the optical imaging lens also satisfies: ALT<9mm, ALG<7mm, ALT/ALG<1.5, wherein ALG is the sum of the air gaps from the first lens to the imaging plane on the optical axis, and ALT is the sum of the thicknesses of six lenses from the first lens to the sixth lens on the optical axis.

Beneficial technical effects of the present invention:

The present invention adopts six lenses and designs each lens accordingly, so as to have a large relative aperture and increase the recognition range; the overall volume is small, the total length is short, and the weight is light, so as to realize the requirement of miniaturization; the distortion is well corrected and the serious pixel loss under the condition of correcting the distortion is reduced; the relative illumination is controlled to ensure the relative illumination is uniform under the condition of large relative aperture; the optical transfer function is well controlled, the resolution is high, and the imaging quality is good.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

FIG1 is a schematic diagram of the structure of Embodiment 1 of the present invention;

FIG2 is an MTF diagram of infrared 925nm-960nm of the first embodiment of the present invention;

FIG3 is a relative illumination diagram of infrared 940nm according to the first embodiment of the present invention;

FIG4 is a diagram of field curvature and distortion according to the first embodiment of the present invention;

FIG5 is a schematic diagram of the structure of Embodiment 2 of the present invention;

FIG6 is an MTF diagram of infrared 925nm-960nm of the second embodiment of the present invention;

FIG7 is a relative illumination diagram of infrared 940nm according to the second embodiment of the present invention;

FIG8 is a diagram of field curvature and distortion according to the second embodiment of the present invention;

FIG9 is a schematic diagram of the structure of Embodiment 3 of the present invention;

FIG10 is an infrared 925nm-960nm MTF diagram of Embodiment 3 of the present invention;

FIG11 is a relative illumination diagram of infrared 940nm according to the third embodiment of the present invention;

FIG12 is a diagram of field curvature and distortion according to Embodiment 3 of the present invention;

FIG13 is a schematic diagram of the structure of Embodiment 4 of the present invention;

FIG14 is an infrared 925nm-960nm MTF diagram of the fourth embodiment of the present invention;

FIG15 is a relative illumination diagram of infrared 940nm according to the fourth embodiment of the present invention;

FIG. 16 is a diagram showing field curvature and distortion according to the fourth embodiment of the present invention.

DETAILED DESCRIPTION

To further illustrate the various embodiments, the present invention provides drawings. These drawings are part of the disclosure of the present invention, which are mainly used to illustrate the embodiments and can be used in conjunction with the relevant descriptions in the specification to explain the operating principles of the embodiments. With reference to these contents, a person of ordinary skill in the art should be able to understand other possible implementations and advantages of the present invention. The components in the figures are not drawn to scale, and similar component symbols are generally used to represent similar components.

The present invention will now be further described with reference to the accompanying drawings and specific implementation methods.

The term "a lens having a positive refractive power (or a negative refractive power)" means that the paraxial refractive power of the lens calculated by Gaussian optical theory is positive (or negative). The term "object side (or image side) of the lens" is defined as a specific range of the lens surface through which the imaging light passes. The concave and convex shape of the lens surface can be determined by the judgment method of the general knowledgeable person in this field, that is, the concave and convex shape of the lens surface can be determined by the positive and negative signs of the radius of curvature (abbreviated as R value). R value can be commonly used in optical design software, such as Zemax or CodeV. R value is also commonly found in the lens data sheet of optical design software. For the object side, when the R value is positive, the object side is determined to be convex; when the R value is negative, the object side is determined to be concave. Conversely, for the image side, when the R value is positive, the image side is determined to be concave; when the R value is negative, the image side is determined to be convex.

The present invention discloses a small optical imaging lens with large light transmission, which comprises a first lens to a sixth lens in sequence along an optical axis from an object side to an image side; the first lens to the sixth lens each comprises an object side surface facing the object side and allowing imaging light to pass through, and an image side surface facing the image side and allowing imaging light to pass through.

The first lens has a negative refractive power, the object side surface of the first lens is a convex surface, and the image side surface of the first lens is a concave surface.

The second lens has a negative refractive power, the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a concave surface.

The third lens element has positive refractive power, and the object side surface of the third lens element is convex.

The fourth lens element has a positive refractive power, the object side surface of the fourth lens element is a concave surface, and the image side surface of the fourth lens element is a convex surface.

The fifth lens element has a positive refractive power, the object side surface of the fifth lens element is a convex surface, and the image side surface of the fifth lens element is a convex surface.

The sixth lens element has a negative refractive power, the object side surface of the sixth lens element is a convex surface, and the image side surface of the sixth lens element is a concave surface.

The object side surface and the image side surface of the third lens are both aspherical surfaces, or the object side surface and the image side surface of the fourth lens are both aspherical surfaces, so as to improve high-order spherical aberration and coma, increase the relative aperture, and minimize the effective diameter of the aspherical surface to reduce the system cost.

The optical imaging lens has only the first to sixth lenses mentioned above as lenses with refractive power. The present invention uses six lenses, and through corresponding design of each lens, has the advantages of large relative aperture, increased recognition range; small overall volume, short total length, light weight, and can achieve miniaturization requirements; better correction of distortion, reducing serious pixel loss under the condition of distortion correction; control of relative illumination, ensuring uniform relative illumination under large relative aperture conditions; better control of optical transfer function, high resolution, and good imaging quality.

Preferably, an aperture is further included, and the aperture is arranged between the third lens and the fourth lens to reduce the process difficulty and improve the assembly yield.

More preferably, the optical imaging lens also satisfies: nd3≥1.85, wherein nd3 is the refractive index of the third lens, and a high refractive index material is used in front of the aperture to effectively reduce the aperture, make the structure more compact, and help improve the resolution.

Preferably, the optical imaging lens also satisfies: 2.7<|f1/f|<3.8 and 2.7<|f2/f|<3.8, wherein f1 is the focal length of the first lens, f2 is the focal length of the second lens, and f is the focal length of the optical imaging lens, so as to further correct the distortion and improve the lens resolution.

Preferably, the optical imaging lens also satisfies: vd2≥38, wherein vd2 is the dispersion coefficient of the second lens, so as to further optimize the primary aberration and improve the image quality.

Preferably, the optical imaging lens also satisfies: nd5>1.8, wherein nd5 is the refractive index of the fifth lens, which can effectively reduce the primary aberration.

Preferably, the optical imaging lens also satisfies: 1.51≤nd1≤nd2, 1.68≤nd4≤nd3≤2.1 and 1.49≤nd6≤nd5≤2.1, wherein nd1, nd2, nd3, nd4, nd5 and nd6 are the refractive indices of the first lens, the second lens, the third lens, the fourth lens, the fifth lens and the sixth lens, respectively, which can effectively correct the aberrations caused by the large aperture optical system, is conducive to improving the overall resolution and better improving the system performance.

Preferably, the optical imaging lens further satisfies: |Φ3|≤0.16mm ^-1 , |Φ4|≤0.21mm ^-1 , |Φ5|≤0.2mm ^-1 , |Φ6|≤0.15mm ^-1 , wherein Φ3 is the focal power of the third lens, Φ4 is the focal power of the fourth lens, Φ5 is the focal power of the fifth lens, and Φ6 is the focal power of the sixth lens, thereby reducing the sensitivity of the optical imaging lens to various tolerances and improving the production yield of the optical imaging lens.

Preferably, the optical imaging lens further satisfies: ALT<9mm, ALG<7mm, ALT/ALG<1.5, wherein ALG is the sum of the air gaps from the first lens to the imaging plane on the optical axis, and ALT is the sum of the thicknesses of six lenses from the first lens to the sixth lens on the optical axis, thereby further shortening the system length of the optical imaging lens, facilitating processing and manufacturing, and optimizing the system configuration.

The small-sized and high-light-through optical imaging lens of the present invention will be described in detail below with reference to specific embodiments.

Embodiment 1

As shown in FIG1 , a small optical imaging lens with large light transmission includes, from the object side A1 to the image side A2 along an optical axis I, a first lens 1, a second lens 2, a third lens 3, an aperture 7, a fourth lens 4, a fifth lens 5, a sixth lens 6, a filter 8 and an imaging surface 9; each of the first lens 1 to the sixth lens 6 includes an object-side surface facing the object side A1 and allowing imaging light to pass through, and an image-side surface facing the image side A2 and allowing imaging light to pass through.

The first lens 1 has a negative refractive power, an object-side surface 11 of the first lens 1 is a convex surface, and an image-side surface 12 of the first lens 1 is a concave surface.

The second lens element 2 has a negative refractive power, an object-side surface 21 of the second lens element 2 is a convex surface, and an image-side surface 22 of the second lens element 2 is a concave surface.

The third lens 3 has a positive refractive power, the object-side surface 31 of the third lens 3 is a convex surface, and the image-side surface 32 of the third lens 3 is a concave surface. Of course, in some embodiments, the image-side surface 32 of the third lens may also be a convex surface or a plane surface.

The fourth lens element 4 has a positive refractive power. The object-side surface 41 of the fourth lens element 4 is a concave surface, and the image-side surface 42 of the fourth lens element 4 is a convex surface.

The fifth lens element 5 has a positive refractive power. The object-side surface 51 of the fifth lens element 5 is a convex surface, and the image-side surface 52 of the fifth lens element 5 is a convex surface.

The sixth lens element 6 has a negative refractive power. The object-side surface 61 of the sixth lens element 6 is a convex surface, and the image-side surface 62 of the sixth lens element 6 is a concave surface.

In this specific embodiment, the object-side surface 41 and the image-side surface 42 of the fourth lens 4 are both aspherical surfaces. Of course, in some embodiments, the object-side surface 31 and the image-side surface 32 of the third lens 3 may also be both aspherical surfaces.

Of course, in some embodiments, the aperture 7 may also be disposed between other lenses.

The detailed optical data of this specific embodiment are shown in Table 1-1.

Table 1-1 Detailed optical data of Example 1

In this specific embodiment, the object side surface 41 and the image side surface 42 are defined according to the following aspheric curve formula:

in:

z: Depth of the aspherical surface (the vertical distance between the point on the aspherical surface that is y away from the optical axis and the tangent plane that is tangent to the vertex on the aspherical surface's optical axis).

c: The curvature of the vertex of the aspherical surface.

K: Cone constant.

Radial distance.

r _n : normalization radius (NRADIUS);

u:r/r _n .

a _m : ^is the m ^th Q ^con coefficient.

_Qmcon ^: the ^mth order ^{Qcon polynomial} .

Please refer to the following table for detailed parameter data of each aspheric surface:

surface 41 42 K＝ -3.22E+01 -2.42E-01 a ₄ = -1.483E-02 -7.403E-04 a ₆ = 2.368E-03 -2.357E-04 a ₈ = -1.512E-03 -9.847E-05 a ₁₀ = 2.407E-05 1.411E-05 a ₁₂ = 1.171E-04 -2.946E-07 a ₁₄ = -2.183E-05 -1.841E-07

Please refer to Table 5 for the numerical values of the relevant conditional expressions of this specific embodiment.

The MTF transfer function curve of this specific embodiment is shown in Figure 2. It can be seen that the resolution is high. At 160lp/mm, the transfer function is still greater than 0.3, and the imaging quality is excellent, which can meet the requirements of sensors with more than 1 million pixels. Please refer to Figure 3 for the relative illumination diagram, and it can be seen that the relative illumination is high and the uniformity is good. Please refer to (A) and (B) of Figure 4 for the field curvature and distortion diagrams, and it can be seen that the field curvature and distortion are well corrected.

In this specific embodiment, the focal length of the optical imaging lens is f=2.9 mm; the aperture value FNO=1.2; the field of view angle FOV=76°; the image plane diameter Φ=4.1 mm; the distance TTL from the object side surface 11 of the first lens 1 to the imaging plane 9 on the optical axis I is 15.0 mm, and the maximum aperture D=8.0 mm.

Embodiment 2

As shown in FIG. 5 , the surface profile and refractive power of each lens in this embodiment are the same as those in the first embodiment, and only the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

The detailed optical data of this specific embodiment are shown in Table 2-1.

Table 2-1 Detailed optical data of Example 2

Please refer to the following table for detailed parameter data of each aspheric surface in this specific embodiment:

surface 41 42 K＝ -7.285E+00 -3.174E-01 a ₄ = -1.392E-02 -4.136E-04 a ₆ = 1.678E-03 -4.132E-04 a ₈ = -1.234E-03 -3.584E-05 a ₁₀ = 7.326E-05 9.741E-06 a ₁₂ = 6.722E-05 -1.349E-06 a ₁₄ = -1.335E-05 4.077E-09

Please refer to Table 5 for the numerical values of the relevant conditional expressions of this specific embodiment.

The MTF transfer function curve of this specific embodiment is shown in Figure 6. It can be seen that the resolution is high. At 160lp/mm, the transfer function is still greater than 0.3, and the imaging quality is excellent, which can meet the requirements of sensors with more than 1 million pixels. Please refer to Figure 7 for the relative illumination diagram, which shows that the relative illumination is high and the uniformity is good. Please refer to (A) and (B) of Figure 8 for the field curvature and distortion diagrams, which shows that the field curvature and distortion are well corrected.

In this specific embodiment, the focal length of the optical imaging lens is f=2.9 mm; the aperture value FNO=1.2; the field of view angle FOV=76°; the image plane diameter Φ=4.1 mm; the distance TTL from the object side surface 11 of the first lens 1 to the imaging plane 9 on the optical axis I is 15.0 mm, and the maximum aperture D=8.0 mm.

Embodiment 3

As shown in FIG. 9 , the surface profile and refractive power of each lens in this embodiment are the same as those in the first embodiment, and only the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

The detailed optical data of this specific embodiment are shown in Table 3-1.

Table 3-1 Detailed optical data of Example 3

Please refer to the following table for detailed parameter data of each aspheric surface in this specific embodiment:

Please refer to Table 5 for the numerical values of the relevant conditional expressions of this specific embodiment.

The MTF transfer function curve of this specific embodiment is shown in Figure 10. It can be seen that the resolution is high. At 160lp/mm, the transfer function is still greater than 0.3, and the imaging quality is excellent, which can meet the requirements of sensors with more than 1 million pixels. Please refer to Figure 11 for the relative illumination diagram, and it can be seen that the relative illumination is high and the uniformity is good. Please refer to (A) and (B) of Figure 12 for the field curvature and distortion diagrams, and it can be seen that the field curvature and distortion are well corrected.

In this specific embodiment, the focal length of the optical imaging lens is f=2.9 mm; the aperture value FNO=1.2; the field of view angle FOV=76°; the image plane diameter Φ=4.1 mm; the distance TTL from the object side surface 11 of the first lens 1 to the imaging plane 9 on the optical axis I is 15.0 mm, and the maximum aperture D=8.0 mm.

Embodiment 4

As shown in FIG. 13 , the surface profile and refractive power of each lens in this embodiment are the same as those in the first embodiment, and only the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

The detailed optical data of this specific embodiment are shown in Table 4-1.

Table 4-1 Detailed optical data of Example 4

Please refer to the following table for detailed parameter data of each aspheric surface in this specific embodiment:

surface 41 42 K＝ 1.431E+01 -3.206E-01 a ₄ = -1.426E-02 -1.238E-04 a ₆ = 2.085E-03 -2.128E-04 a ₈ = -1.257E-03 -6.818E-05 a ₁₀ = 1.036E-04 3.468E-05 a ₁₂ = 6.412E-05 -6.474E-06 a ₁₄ = -1.271E-05 4.787E-07

Please refer to Table 5 for the numerical values of the relevant conditional expressions of this specific embodiment.

The MTF transfer function curve of this specific embodiment is shown in Figure 14. It can be seen that the resolution is high. At 160lp/mm, the transfer function is still greater than 0.3, and the imaging quality is excellent, which can meet the requirements of sensors with more than 1 million pixels. Please refer to Figure 15 for the relative illumination diagram, and it can be seen that the relative illumination is high and the uniformity is good. Please refer to (A) and (B) of Figure 16 for the field curvature and distortion diagrams, and it can be seen that the field curvature and distortion are well corrected.

In this specific embodiment, the focal length of the optical imaging lens is f=2.9 mm; the aperture value FNO=1.2; the field of view angle FOV=76°; the image plane diameter Φ=4.1 mm; the distance TTL from the object side surface 11 of the first lens 1 to the imaging plane 9 on the optical axis I is 15.0 mm, and the maximum aperture D=8.0 mm.

Table 5 Values of important parameters of four embodiments of the present invention

First embodiment Second embodiment Third embodiment Fourth embodiment f1 -10.13 -10.92 -9.59 -9.45 f2 -9.77 -9.85 -9.35 -9.66 f 2.9 2.9 2.9 2.9 ∣f1/f∣ 3.49 3.77 3.31 3.26 ∣f2/f∣ 3.37 3.40 3.22 3.33 ALT 8.28 7.83 8.81 8.78 ALG 6.51 6.96 5.98 6.01 ALT/ALG 1.27 1.13 1.47 1.46 ∣Φ3∣ 0.15 0.13 0.14 0.14 ∣Φ4∣ 0.20 0.20 0.19 0.19 ∣Φ5∣ 0.17 0.17 0.19 0.19 ∣Φ6∣ 0.15 0.14 0.13 0.13

Although the present invention has been specifically shown and described in conjunction with the preferred embodiments, it should be understood by those skilled in the art that various changes may be made to the present invention in form and details without departing from the spirit and scope of the present invention as defined by the appended claims, all of which are within the scope of protection of the present invention.

Claims (7)

1. The utility model provides a small-size big optical imaging lens that lets in, its characterized in that: in order from the object side to the image side along an optical axis comprises a first lens to a sixth lens; the first lens element to the sixth lens element each comprise an object side surface facing the object side and allowing the imaging light to pass therethrough, and an image side surface facing the image side and allowing the imaging light to pass therethrough;

The first lens has negative refractive index, the object side surface of the first lens is a convex surface, and the image side surface of the first lens is a concave surface;

The second lens has negative refractive index, the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a concave surface;

The third lens has positive refractive index, and the object side surface of the third lens is a convex surface;

the fourth lens has positive refractive index, the object side surface of the fourth lens is a concave surface, and the image side surface of the fourth lens is a convex surface;

The fifth lens has positive refractive index, the object side surface of the fifth lens is a convex surface, and the image side surface of the fifth lens is a convex surface;

The sixth lens element has negative refractive power, wherein the object-side surface of the sixth lens element is convex, and the image-side surface of the sixth lens element is concave;

The object side surface and the image side surface of the third lens are aspheric, or the object side surface and the image side surface of the fourth lens are aspheric;

the optical imaging lens has the lenses with refractive index, namely the first lens to the sixth lens;

The optical imaging lens satisfies the following conditions: 2.7< - |f1/f| <3.8,2.7< -f2/f| <3.8, ALT <9mm, ALG <7mm, ALT/ALG <1.5, wherein f1 is the focal length of the first lens, f2 is the focal length of the second lens, f is the focal length of the optical imaging lens, ALT is the sum of the thicknesses of the six lenses of the first lens to the sixth lens on the optical axis, and ALG is the sum of the air gaps of the first lens to the imaging surface on the optical axis.

2. The compact, high-pass optical imaging lens of claim 1, wherein: the lens system further comprises a diaphragm, and the diaphragm is arranged between the third lens and the fourth lens.

3. The compact, high-pass optical imaging lens of claim 2, further satisfying: nd3 is not less than 1.85, wherein nd3 is the refractive index of the third lens.

4. The compact, high-pass optical imaging lens of claim 1, further satisfying: vd2 is equal to or greater than 38, wherein vd2 is the dispersion coefficient of the second lens.

5. The compact, high-pass optical imaging lens of claim 1, further satisfying: nd5>1.8, wherein nd5 is the refractive index of the fifth lens.

6. The compact, high-pass optical imaging lens of claim 1, further satisfying: 1.51.ltoreq.nd1.ltoreq.nd2, 1.68.ltoreq.nd4.ltoreq.nd3.ltoreq.2.1, and 1.49.ltoreq.nd6.ltoreq.nd5.ltoreq.2.1, wherein nd1, nd2, nd3, nd4, nd5, and nd6 are refractive indices of the first lens, the second lens, the third lens, the fourth lens, the fifth lens, and the sixth lens, respectively.

7. The compact, high-pass optical imaging lens of claim 1, further satisfying: and [ phi 3 ] is less than or equal to 0.16mm ^-1,∣Φ4∣≤0.21mm^-1,∣Φ5∣≤0.2mm^-1,∣Φ6∣≤0.15mm^-1, wherein [ phi 3 ] is the optical power of the third lens, [ phi 4 ] is the optical power of the fourth lens, [ phi 5 ] is the optical power of the fifth lens, and [ phi 6 ] is the optical power of the sixth lens.