CN114578462A

CN114578462A - Optical imaging lens

Info

Publication number: CN114578462A
Application number: CN202210193581.XA
Authority: CN
Inventors: 蒯泽文; 郑磊; 袁银潮
Original assignee: Zhejiang Sunny Optics Co Ltd
Current assignee: Zhejiang Sunny Optics Co Ltd
Priority date: 2021-03-22
Filing date: 2021-03-22
Publication date: 2022-06-03
Also published as: CN113031124A

Abstract

The invention provides an optical imaging lens. The optical imaging lens includes a lens barrel; the lens comprises a plurality of lenses which are arranged at intervals along the axial direction of the lens barrel; a base layer; the surface of one side of the transition layer is connected with the substrate layer; the microstructure film layer is connected with the surface of the other side of the transition layer, the surface of one side, far away from the base layer, of the microstructure film layer is provided with a plurality of microstructures, and the refractive index of the microstructures is gradually reduced towards the direction far away from the lens. The invention solves the problem of large reflectivity deviation of the surface of the lens in the prior art.

Description

Optical imaging lens

The invention is a divisional application of an invention patent with an application date of 2021, 03 and 22, an application number of 202110304398.8, entitled "microstructure film system, optical imaging lens and method for preparing film system".

Technical Field

The invention relates to the technical field of optical imaging equipment, in particular to an optical imaging lens.

Background

Currently, microstructure optical films are of interest to a large number of optical film researchers due to their excellent optical properties. The belly hole of the moth, the super-hydrophobic property of the lotus leaf and the like are all the microstructure film effects in the nature. The microstructure optical film mainly forms a light trapping effect by preparing an optical film layer with a periodic structure, so that the effect of improving the optical performance of the film is achieved. Microstructured films can be viewed as a mixture of film material and air, with an ultra-low equivalent refractive index.

At present, the mainstream AR film is mainly prepared in an evaporation mode, the Rave at 400-780nm is less than or equal to 0.5%, and due to the inherent angle effect of the coating film on the antireflection principle, and in addition, when the aspheric lens is prepared, the film thickness of the center and the edge of the lens surface has a certain difference (10% -30%), the central reflectivity and the edge reflectivity are obviously different in comprehensive view, and the optical performance of the lens is greatly influenced.

That is, the surface of the lens in the related art has a problem of large reflectance variation.

Disclosure of Invention

The invention mainly aims to provide an optical imaging lens to solve the problem that the surface of a lens in the prior art has large reflectivity deviation.

In order to achieve the above object, according to one aspect of the present invention, there is provided a micro-structured film system comprising: a base layer; the transition layer comprises at least one first transition layer and at least one second transition layer which are stacked, the refractive index of the first transition layer is different from that of the second transition layer, and one side surface of the transition layer is connected with the substrate layer; the microstructure film layer is connected with the surface of the other side of the transition layer, a plurality of microstructures arranged at intervals are arranged on the surface of one side, away from the base layer, of the microstructure film layer, and the refractive index of the microstructures is arranged in a gradient mode in the direction perpendicular to the base layer.

Further, the refractive index of the microstructure is 1 or more and 1.3 or less.

Further, when the first transition layer and/or the second transition layer is plural, the first transition layer and the second transition layer are alternately stacked.

Further, the refractive index of the base layer is 1.4 or more and 1.7 or less.

Further, the refractive index of the first transition layer is 1.5 or more and 2.5 or less.

Further, the refractive index of the second transition layer is 1.4 or more and 1.5 or less.

Further, the material of the base layer comprises one of APEL, EP, K9, K26R.

Further, the material of the microstructure film layer is an inorganic medium material or an organic polymer.

Further, the material of the microstructured film layer comprises AL₂O₃、CaO、CuO、Er₂O₃、Ga₂O₃、HfO₂、La₂O₃、MgO、Nb₂O₅、Sc₂O₃、SiO₂、Ta₂O₅、TiO₂、VXOY、Y₂O₃、Yb₂O₃、ZnO、ZrO₂、AlN、GaN、TaNX、TiAlN、TiNX、TaC、TiC、ZnS、SrS、CaF₂、LaF₃、MgF₂、SrF₂And a resin.

Further, the length of the microstructure in a direction perpendicular to the base layer is 10nm or more and 1000nm or less.

Further, the length of the microstructure in a direction parallel to the base layer is 10nm or more and 1000nm or less.

Further, the cross-sectional area of the microstructure along a direction parallel to the base layer gradually decreases toward a direction away from the base layer.

Further, the microstructure is triangular in cross section in a direction perpendicular to the base layer.

Further, the surface of the microstructure film system has a maximum reflectance of 0.2% or less with respect to light having a wavelength of 430nm to 780 nm.

Further, the average reflectance of the surface of the microstructured film system to light having a wavelength of 430nm to 780nm is 0.1% or less.

Further, the difference in reflectivity at each location of the surface of the microstructured film system is less than 2%.

According to another aspect of the present invention, there is provided an optical imaging lens including: a lens barrel; the lens comprises a plurality of lenses which are arranged at intervals along the axial direction of the lens barrel; the microstructure film system is arranged on the surface of at least one lens.

According to another aspect of the present invention, there is provided an optical imaging lens including: a lens barrel; a plurality of lenses which are arranged in the lens barrel at intervals; a base layer disposed on at least one side surface of the at least one lens; the microstructure film layer is arranged on the surface of one side, far away from the lens, of the base layer, the surface, far away from the lens, of the microstructure film layer is provided with a plurality of microstructures arranged at intervals, and the refractive index of the microstructures in the direction perpendicular to the lens is gradually reduced.

Further, the length of the microstructure in a direction perpendicular to the lens is 10nm or more and 1000nm or less.

Further, the length of the microstructure in a direction parallel to the lens is 10nm or more and 1000nm or less.

Further, the cross-sectional area of the microstructure along a direction parallel to the lens is gradually reduced toward a direction away from the lens.

Further, the average reflectivity of the surface of the microstructure film layer to light with the wavelength of 430nm to 780nm is less than or equal to 0.3%.

Further, the refractive index of the lens is 1.4 or more and 1.7 or less.

Further, the material of the lens comprises one of APEL, EP, K9, K26R.

Further, the refractive index of the microstructure film layer is greater than or equal to 1 and less than 1.3.

According to another aspect of the present invention, there is provided a method of preparing a film system, the method of preparing a film system being used to prepare the above-mentioned microstructured film system, the method of preparing a film system comprising: depositing a first transition layer of the microstructure film system and a second transition layer of the microstructure film system on at least one side surface of the base layer of the microstructure film system to form a transition layer of the microstructure film system; preparing a microstructure film layer of the microstructure film system on the surface of one side of the transition layer, which is far away from the substrate layer, by using an atomic layer deposition technology, and forming a microstructure on the surface of the microstructure film layer.

Further, the process of depositing the first transition layer of the microstructure film system and the second transition layer of the microstructure film system on at least one side surface of the base layer of the microstructure film system to form the transition layer of the microstructure film system comprises: the first transition layer and the second transition layer are alternately deposited by a physical vapor deposition technique.

By applying the technical scheme of the invention, the microstructure film system comprises a substrate layer, a transition layer and a microstructure film layer, wherein the transition layer comprises at least one first transition layer and at least one second transition layer which are overlapped; the microstructure film layer is connected with the surface of the other side of the transition layer, the surface of one side, away from the substrate layer, of the microstructure film layer is provided with a plurality of microstructures arranged at intervals, and the refractive index of each microstructure is arranged in a gradient mode along the direction perpendicular to the substrate layer.

By arranging the transition layer on the microstructure film system, the requirement on the substrate layer is greatly reduced, so that the microstructure film system can be better matched with the microstructure film layer, and the application range of the microstructure film layer is greatly enlarged. The refractive indexes of the first transition layer and the second transition layer are different, so that light rays can be deflected at different angles when propagating in the first transition layer and the second transition layer, and the uniformity of the light rays transmitted to the base layer is improved. Meanwhile, the reflectivity of the edge of the microstructure film system to light can be reduced, so that the transmittance of the light is increased, the relative illumination is increased, the vignetting phenomenon is reduced, and the working stability of the microstructure film system is improved. The arrangement of the micro-structure film layer greatly reduces the smoothness of the micro-structure film system, so that the absorption effect of the micro-structure film layer on light rays is increased, and the reflection effect of the micro-structure film system is greatly reduced. The microstructure is arranged on the surface of the microstructure film system, so that light can be reflected and refracted among the microstructures, the transmittance of the microstructure film system to the light is increased, the loss of imaging light is reduced, and the imaging quality is improved. In addition, be the gradient setting with the refracting index of microstructure along the direction of perpendicular to stratum basale to the skew of different angles takes place for light when the inside of microstructure is propagated, further reduces the reflection of light, has increaseed the refraction effect to light, has increased the homogeneity of the light of transmitting the stratum basale department.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

FIG. 1 shows a schematic structural diagram of a microstructured film system according to an alternative embodiment of the present invention; and

FIG. 2 illustrates an angular topographical view of the microstructure of the microstructured film layer of FIG. 1;

FIG. 3 illustrates another angular topographical view of the microstructure of the microstructured film layer of FIG. 1;

fig. 4 shows a schematic configuration diagram of an optical system of comparative example one of the present invention;

FIG. 5 shows the change of reflectance curves at different incident angles for the control group of comparative example one of the present invention;

FIG. 6 shows the change of reflectance curves at different incident angles for the experimental group of comparative example one of the present invention;

FIG. 7 is a schematic view showing the structure of an optical system of a comparative example second of the present invention;

FIG. 8 shows the change of reflectance curves at different incident angles for the control group of comparative example two of the present invention;

FIG. 9 shows the change of reflectance curves at different incident angles for the experimental group of comparative example two of the present invention;

FIG. 10 is a schematic view showing the structure of an optical system of comparative example three of the present invention;

FIG. 11 shows the change of reflectance curves at different incident angles for the control of comparative example three of the present invention;

FIG. 12 shows the change of reflectance curves at different incident angles for the experimental group of comparative example three of the present invention;

fig. 13 is a schematic view showing the structure of an optical system of comparative example four of the present invention;

FIG. 14 shows the change of reflectance curves at different incident angles for the control of comparative example four of the present invention;

FIG. 15 shows the change of reflectance curves at different incident angles for the experimental group of comparative example four of the present invention;

fig. 16 is a schematic view showing a configuration of an optical system of comparative example five of the present invention;

FIG. 17 shows the change of reflectance curves at different incident angles for the control of comparative example five of the present invention;

FIG. 18 shows the change of reflectance curves at different incident angles for the experimental group of comparative example five of the present invention;

fig. 19 is a schematic view showing the structure of an optical system of comparative example six of the present invention;

FIG. 20 shows the change of reflectance curves at different incident angles for the control of comparative example six of the present invention;

FIG. 21 shows the change in reflectance curves at different angles of incidence for the experimental group of comparative example six of the present invention;

FIG. 22 shows a ghost energy diagram of a conventional PVD membrane system of the present invention;

FIG. 23 shows a ghost energy diagram of a microstructured film system of the present invention;

FIG. 24 is a graph showing the relationship between the height of a microstructure and the reflectance of the microstructure in the present invention;

fig. 25 shows a schematic structural diagram of a microstructured film layer in a third embodiment of the invention.

Wherein the figures include the following reference numerals:

10. a base layer; 20. a transition layer; 21. a first transition layer; 22. a second transition layer; 30. a microstructure film layer; 31. a microstructure; e1, first lens; e2, second lens; e3, third lens; e4, fourth lens; e5, fifth lens; e6, sixth lens; e7, seventh lens; e8, eighth lens; e9, ninth lens; e10, a filter plate; s1, the object side surface of the first lens; s2, an image side surface of the first lens; s3, the object side surface of the second lens; s4, an image side surface of the second lens; s5, the object side surface of the third lens; the image side surface of the third lens element (S6); s7, the object side surface of the fourth lens; s8, an image side surface of the fourth lens element; s9, the object side surface of the fifth lens; s10, an image side surface of the fifth lens element; s11, the object-side surface of the sixth lens element; s12, an image side surface of the sixth lens element; s13, an object-side surface of the seventh lens; s14, an image side surface of the seventh lens element; s15, an object-side surface of the eighth lens element; s16, an image side surface of the eighth lens element; s17, the object-side surface of the ninth lens element; s18, the image-side surface of the ninth lens element; s19, the object side surface of the filter plate; s20, the image side surface of the filter plate; s21, imaging surface; STO, stop.

Detailed Description

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.

It is noted that, unless otherwise indicated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

In the present invention, unless specified to the contrary, use of the terms of orientation such as "upper, lower, top, bottom" or the like, generally refer to the orientation as shown in the drawings, or to the component itself in a vertical, perpendicular, or gravitational orientation; likewise, for ease of understanding and description, "inner and outer" refer to the inner and outer relative to the profile of the components themselves, but the above directional words are not intended to limit the invention.

The invention provides an optical imaging lens, aiming at solving the problem that the surface of a lens in the prior art has large reflectivity deviation.

Example one

As shown in fig. 1 to 3 and 16 to 24, the microstructure film system includes a base layer 10, a transition layer 20 and a microstructure film layer 30, wherein the transition layer 20 includes at least one first transition layer 21 and at least one second transition layer 22 which are stacked, the first transition layer 21 and the second transition layer 22 have different refractive indexes, and one side surface of the transition layer 20 is connected to the base layer 10; the microstructure film layer 30 is connected with the other side surface of the transition layer 20, a side surface of the microstructure film layer 30 away from the base layer 10 is provided with a plurality of microstructures 31 arranged at intervals, and the refractive index of the microstructures 31 is arranged in a gradient manner along a direction perpendicular to the base layer 10.

By arranging the transition layer 20 on the microstructure film system, the requirement on the substrate layer 10 is greatly reduced, so that the microstructure film system can be better matched with the microstructure film layer 30, and the application range of the microstructure film layer 30 is greatly increased. The refractive indices of the first transition layer 21 and the second transition layer 22 are different, so that the light rays can be deflected at different angles when propagating in the first transition layer 21 and the second transition layer 22, so as to increase the uniformity of the light rays transmitted to the substrate layer 10. Meanwhile, the reflectivity of the edge of the microstructure film system to light can be reduced, so that the transmittance of the light is increased, the relative illumination is increased, the vignetting phenomenon is reduced, and the working stability of the microstructure film system is improved. The arrangement of the micro-structure film layer 30 greatly reduces the smoothness of the micro-structure film system, thereby increasing the absorption effect of the micro-structure film layer on light rays and greatly reducing the reflection effect of the micro-structure film system. The microstructures 31 are arranged on the surface of the microstructure film system, so that light can be reflected and refracted among the microstructures 31, the transmittance of the microstructure film system to the light is increased, the loss of imaging light is reduced, and the imaging quality is improved. In addition, the refractive index of the microstructure 31 is set in a gradient manner along the direction perpendicular to the substrate layer 10, so that the light rays are deflected at different angles when propagating inside the microstructure 31, the reflection of the light rays is further reduced, the refraction effect of the light rays is increased, and the uniformity of the light rays transmitted to the substrate layer 10 is increased.

Specifically, the refractive index of the microstructure 31 is 1 or more and 1.3 or less. The refractive index of the microstructure 31 is smaller and is closer to that of air, so that light rays in the air can be ensured to be smoothly emitted into the microstructure film layer 30, the reflection of the light is greatly reduced, and the efficiency of emitting the light in the air into the microstructure film system is increased. Alternatively, the refractive index of the microstructure 31 may be 1, 1.05, 1.1, 1.15, 1.2, 1.25.

As shown in fig. 24, the refractive index of the microstructure 31 gradually decreases in a direction away from the lens. Or the refractive index is higher the closer to the lens in the microstructure 31.

Alternatively, when the first transition layer 21 and the second transition layer 22 are plural, the first transition layer 21 and the second transition layer 22 are alternately stacked. The first transition layers 21 and the second transition layers with different refractive indexes are alternately superposed, so that light can be transmitted in different refraction film layers to be deflected for many times, the reflectivity of the edge of the microstructure film system to the light is reduced, the transmittance of the light is increased, the relative illumination is increased, the vignetting phenomenon is reduced, and the optical consistency of each position of the microstructure film system is better.

Specifically, the refractive index of the base layer 10 is 1.4 or more and 1.7 or less. The arrangement makes the refractive index of the substrate layer 10 relatively close to that of the first transition layer 21 and the second transition layer 22, so that when light enters the substrate layer 10, the generated reflected light is less, and the light transmittance of the substrate layer 10 is ensured.

Alternatively, the refractive index of the substrate layer 10 may be 1.4, 1.45, 1.5, 1.55, 1.6, 1.65, 1.7.

Specifically, the refractive index of the first transition layer 21 is 1.5 or more and 2.5 or less. This arrangement provides a higher refractive index for the first transition layer 21, so that light entering the first transition layer 21 is deflected more, and thus the distribution of light reaching the substrate layer 10 is more uniform. Alternatively, the refractive index of the first transition layer 21 may be 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5.

Specifically, the refractive index of the second transition layer 22 is 1.4 or more and 1.5 or less. Set up like this and make certain refractive index difference between second transition layer 22 and the first transition layer 21 for light is different at the deflection of second transition layer 22 and the deflection direction and the deflection angle in first transition layer 21, and then greatly increased the variety of light in the reflection reducing membrane system deflection, the reflection of the light that has significantly reduced makes the more even of the light distribution that reachs stratum basale 10.

Alternatively, the refractive index of the second transition layer 22 may be 1.4, 1.42, 1.45, 1.47, 1.49, 1.5.

Specifically, the material of the base layer 10 includes one of APEL, EP, K9, K26R. The base layer 10 is made of an optical base material, so that the base layer 10 and the transition layer 20 are better matched, light can be conveniently transmitted in the micro-structural film system, and the working stability of the micro-structural film system is improved.

Optionally, the material of the microstructure film layer 30 is an inorganic dielectric material or an organic polymer. The arrangement makes the refractive index of the microstructure film layer 30 closer to that of air, so that light rays in the air can be conveniently emitted into the microstructure film layer 30, and the reduction of the reflection of the microstructure film layer 30 to the light rays is facilitated.

Specifically, the material of the microstructure film layer 30 includes one of AL2O3, CaO, CuO, Er2O3, Ga2O3, HfO2, La2O3, MgO, Nb2O5, Sc2O3, SiO2, Ta2O5, TiO2, VXOY, Y2O3, Yb2O3, ZnO, ZrO2, AlN, GaN, TaNX, TiAlN, TiNX, TaC, TiC, ZnS, SrS, CaF2, LaF3, MgF2, SrF2, and resin.

In the present embodiment, the length of the microstructure 31 in the direction perpendicular to the base layer 10 is 10nm or more and 1000nm or less. The length of the microstructure 31 is limited within the range of 10nm to 1000nm, so that the light reflection rate of the microstructure film system can be reduced while the propagation efficiency of light in the microstructure film system is ensured, and the manufacture of the microstructure 31 is facilitated as far as possible. Preferably, the length of the microstructures 31 in the direction perpendicular to the base layer 10 is greater than 50nm and less than 400 nm.

In the present embodiment, the length of the microstructure 31 in the direction parallel to the base layer 10 is 10nm or more and 1000nm or less. This arrangement allows for as many microstructures 31 as possible to be added due to the limited area of the lens, thereby resulting in less differences in reflectivity at each location of the microstructure film train. Preferably, the length of the microstructures 31 in a direction parallel to the base layer 10 is greater than 50nm and less than 200 nm.

Specifically, the cross-sectional area of the microstructure 31 in the direction parallel to the base layer 10 is gradually reduced toward the direction away from the base layer 10. The distance between the ends of the microstructures 31 far away from the substrate layer 10 is large, so that the optical incidence into the microstructure film layer 30 is facilitated, and the light reflectivity of the microstructure film layer 30 is greatly reduced.

As shown in fig. 1, the microstructure 31 has a triangular shape in a cross section perpendicular to the base layer 10. The microstructure 31 is arranged in a triangular shape, so that the plane area of the surface of the microstructure film layer 30 is smaller, the reflectivity of light on the surface of the microstructure film system is greatly reduced, and the transmittance of the light is increased.

In the present embodiment, the maximum reflectance of the surface of the microstructure film system to light having a wavelength of 430nm to 780nm is 0.2% or less. The arrangement enables the surface of the microstructure film system to have smaller reflectivity, and further increases the light transmittance of the microstructure film system.

In the present embodiment, the average reflectance of the surface of the microstructured film system for light having a wavelength of 430nm to 780nm is 0.1% or less. The arrangement enables the surface of the microstructure film system to have smaller reflectivity, and further increases the light transmittance of the microstructure film system.

In the present embodiment, the difference in reflectance at each position of the surface of the microstructure film system is less than 2%. The arrangement ensures that the surface of the microstructure film system has better consistency and the reflectivity difference of each position is smaller, so that the optical performance difference of the surface of the lens is smaller, and the imaging quality is ensured.

The microstructure film system is prepared by a method for preparing the film system, and the method for preparing the film system comprises the following steps: depositing a first transition layer 21 of the microstructure film system and a second transition layer 22 of the microstructure film system on at least one side surface of the base layer 10 of the microstructure film system to form a transition layer 20 of the microstructure film system; preparing a microstructure film layer 30 of the microstructure film system on the surface of the transition layer 20 far away from the base layer 10 by using an atomic layer deposition technology, and forming a microstructure 31 on the surface of the microstructure film layer 30. The transition layer 20 is formed by alternately plating the first transition layer 21 and the second transition layer 22 on the surface of the base layer 10, so that the refractive indexes of the base layer 10 and the microstructure film layer 30 are better matched, and the reflectivity of the microstructure film system can be further reduced. The transition layer 20 is prepared by a vapor deposition method. The atomic layer deposition is a monoatomic layer coating technology for forming a film system by alternately introducing gas-phase precursor pulses into a reactor and carrying out chemical adsorption and reaction on a deposition substrate, and when the precursor reaches the surface of the deposition substrate, the precursor is chemically adsorbed on the surface of the deposition substrate and carries out surface reaction, so that one atomic layer is deposited in the ALD coating process every time, the film thickness is accurately controlled, an angle effect does not exist in the coating process any more, and the substrate conformality is better. Processing is performed on the surface of the microstructure film layer 30 to form the microstructures 31. The microstructure 31 can be prepared by ion beam etching, reactive ion etching, sol-gel method, hydrothermal method, chemical solvent etching method, or the like. It is only necessary that the height of the microstructure 31 is 10-1000nm and the width is 10-1000 nm.

Specifically, the process of depositing the first transition layer 21 of the microstructure film system and the second transition layer 22 of the microstructure film system on at least one side surface of the base layer 10 of the microstructure film system to form the transition layer 20 of the microstructure film system comprises the following steps: the first transition layer 21 and the second transition layer 22 are alternately deposited by a physical vapor deposition technique. The arrangement greatly reduces the production cost under the condition of reducing the surface reflectivity of the microstructure film system.

Stray light and ghost images have been a technical drawback that cannot be eliminated because of the large reflectivity and significant angular effects of conventional PVD film systems, and the use of microstructured film systems in this application is sufficient to reduce the stray and ghost image energies to undetectable levels. As shown in fig. 22, a lens coated with a conventional PVD film system,ghost image energy range is 3.3E^-7～4.86E^-7. As shown in FIG. 23, the ghost image energy range of the lens coated with the microstructure film system of the present application is 0.9E^-72.16E-7, ghost energy is reduced by more than 60%.

Example two

Specifically, the optical imaging lens comprises a lens barrel, a plurality of lenses and the microstructure film system, wherein the plurality of lenses are arranged at intervals along the axial direction of the lens barrel; the microstructured film is disposed on a surface of at least one lens. The microstructure film system is arranged on the lens, so that the optical consistency of the surface of the lens is better, the reflectivity of each position of the lens is smaller, the loss of imaging light is reduced, and the imaging quality of the optical imaging lens is ensured.

As shown in fig. 13 and fig. 6 to 23, the microstructure film system includes a base layer 10, a transition layer 20 and a microstructure film layer 30, wherein the transition layer 20 includes at least one first transition layer 21 and at least one second transition layer 22 which are stacked, the first transition layer 21 and the second transition layer 22 have different refractive indexes, and one side surface of the transition layer 20 is connected to the base layer 10; the microstructure film layer 30 is connected with the other side surface of the transition layer 20, a side surface of the microstructure film layer 30 away from the base layer 10 is provided with a plurality of microstructures 31 arranged at intervals, and the refractive index of the microstructures 31 is arranged in a gradient manner along a direction perpendicular to the base layer 10.

Specifically, the refractive index of the microstructure 31 is 1 or more and 1.3 or less. The refractive index of the microstructure 31 is smaller and is closer to that of air, so that light rays in the air can be ensured to be smoothly emitted into the microstructure film layer 30, the reflection of the light is greatly reduced, and the efficiency of the light rays in the air emitted into the microstructure film system is increased. Alternatively, the refractive index of the microstructure 31 may be 1, 1.05, 1.1, 1.15, 1.2, 1.25.

Alternatively, when the first transition layer 21 and the second transition layer 22 are plural, the first transition layer 21 and the second transition layer 22 are alternately stacked. The first transition layers 21 and the second transition layers 22 with different refractive indexes are alternately superposed, so that light can be deflected for many times in different refraction film layers in transmission, the reflectivity of the edge of the microstructure film system to the light is reduced, the transmittance of the light is increased, the relative illumination is increased, the vignetting phenomenon is reduced, and the optical consistency of each position of the microstructure film system is better.

Specifically, the material of the base layer 10 includes one of APEL, EP, K9, and K26R. The base layer 10 is made of an optical base material, so that the base layer 10 and the transition layer 20 are better matched, light can be conveniently transmitted in the micro-structural film system, and the working stability of the micro-structural film system is improved.

Specifically, the material of the microstructured film layer 30 includes AL₂O₃、CaO、CuO、Er₂O₃、Ga₂O₃、HfO₂、La₂O₃、MgO、Nb₂O₅、Sc₂O₃、SiO₂、Ta₂O₅、TiO₂、VXOY、Y₂O₃、Yb₂O₃、ZnO、ZrO₂、AlN、GaN、TaNX、TiAlN、TiNX、TaC、TiC、ZnS、SrS、CaF₂、LaF₃、MgF₂、SrF₂And a resin.

In the present embodiment, the length of the microstructure 31 in the direction perpendicular to the base layer 10 is 10nm or more and 1000nm or less. The length of the microstructure 31 is limited within the range of 10nm to 1000nm, so that the light reflection rate of the microstructure film system can be reduced while the propagation efficiency of light in the microstructure film system is ensured, and the manufacture of the microstructure 31 is facilitated as far as possible. Preferably, the length of the microstructure layer 31 in the direction perpendicular to the substrate layer 10 is 50nm or more and 400nm or less.

In the present embodiment, the length of the microstructure 31 in the direction parallel to the base layer 10 is 10nm or more and 1000nm or less. This arrangement allows for as many microstructures 31 as possible to be added due to the limited area of the lens, thereby resulting in less differences in reflectivity at each location of the microstructure film train. Preferably, the length of the microstructure 31 in a direction parallel to the base layer 10 is greater than 50nm and equal to or less than 200 nm.

In this embodiment, the average reflectance of the surface of the microstructured film system to light having a wavelength of 430nm to 780nm is 0.1% or less. The arrangement enables the surface of the microstructure film system to have smaller reflectivity, and further increases the light transmittance of the microstructure film system.

In the present embodiment, the difference in reflectance at each position of the surface of the microstructure film system is less than 2%. The arrangement ensures that the surface of the microstructure film system has better consistency, the difference of the reflectivity of each position is smaller, the difference of the optical performance of the surface of the lens is smaller, and the imaging quality is ensured.

EXAMPLE III

As shown in fig. 1 to 15 and fig. 22 to 25, the optical imaging lens includes a lens barrel, a plurality of lenses, a substrate layer 10 and a microstructure film layer 30, wherein the plurality of lenses are arranged in the lens barrel at intervals; a base layer 10 is disposed on at least one side surface of at least one lens; the microstructure film layer 30 is disposed on a surface of the substrate layer 10 away from the lens, a surface of the microstructure film layer 30 away from the lens has a plurality of microstructures 31 arranged at intervals, and a refractive index of the microstructures 31 in a direction perpendicular to the lens is gradually reduced.

By arranging the microstructure film layer 30 on the lens, the smoothness of the surface of the lens is greatly reduced, the absorption effect of the lens on light rays is further increased, and the reflection effect of the lens is greatly reduced. The microstructures 31 are arranged on the surface of the microstructure film layer, so that light can be reflected and refracted among the microstructures 31, the transmittance of the microstructure film layer to the light is increased, the loss of imaging light is reduced, and the imaging quality is improved. In addition, the refractive index of the microstructure 31 is set in a gradient manner along the direction perpendicular to the lens, so that light rays are deflected at different angles when being transmitted inside the microstructure 31, the reflection of the light rays is further reduced, the refraction effect of the light rays is enhanced, the uniformity of the light rays transmitted to the lens is increased, and the imaging quality of the optical imaging lens is ensured.

In the present embodiment, the length of the microstructure 31 in the direction perpendicular to the lens is 10nm or more and 1000nm or less. The length of the microstructure 31 is limited within the range of 10nm to 1000nm, so that the transmission efficiency of light rays in the microstructure film layer is ensured, the reflectivity of the microstructure film layer to the light rays can be reduced, and the manufacture of the microstructure 31 is facilitated as far as possible. Preferably, the length of the microstructure layer 31 in the direction perpendicular to the lenses is 50nm or more and 400nm or less.

In the present embodiment, the length of the microstructure 31 in the direction parallel to the lens is 10nm or more and 1000nm or less. This arrangement allows for as many microstructures 31 as possible to be added due to the limited area of the lens, thereby resulting in less difference in reflectivity at each location of the microstructured film layer 30. Preferably, the length of the microstructure layer 31 in a direction parallel to the lenses is greater than 50nm and equal to or less than 400 nm.

Specifically, the cross-sectional area of the microstructure 31 in the direction parallel to the lens is gradually reduced toward the direction away from the lens. The distance between the microstructures 31 at the end far away from the lens is larger, so that light rays can be favorably emitted into the microstructure film layer 30, and the light reflectivity of the microstructure film layer 30 is greatly reduced.

As shown in fig. 1, the microstructure 31 has a triangular shape in a cross section in a direction perpendicular to the base layer 10. The microstructures 31 are arranged in a triangular shape, so that the plane area of the surface of the microstructure film layer 30 is small, the reflectivity of light on the surface of the microstructure film layer 30 is greatly reduced, and the transmittance of the light is increased.

Specifically, the average reflectivity of the surface of the microstructure film layer 30 to light with a wavelength of 430nm to 780nm is less than or equal to 0.3%. The arrangement enables the reflectivity of the surface of the microstructure film layer to be smaller, and further the light transmittance of the microstructure film layer is increased.

Specifically, the refractive index of the lens is 1.4 or more and 1.7 or less. The arrangement makes the refractive index of the lens and the microstructure film layer 30 relatively close, so that when light rays enter the lens, the generated reflected light is less, and the light transmittance of the lens is ensured.

Alternatively, the refractive index of the lens may be 1.4, 1.45, 1.5, 1.55, 1.6, 1.65, 1.7.

Specifically, the material of the lens includes one of APEL, EP, K9, K26R. The lens is made of optical substrate material, so that the lens and the microstructure film layer 30 are better matched, light can be conveniently transmitted in the microstructure film layer 30, and the working stability of the microstructure film layer 30 is improved.

Specifically, the refractive index of the microstructure film layer 30 is 1 or more and less than 1.3. The refractive index of the micro-structure film layer 30 is smaller and is closer to that of air, so that light rays in the air can be guaranteed to be smoothly injected into the micro-structure film layer 30, reflection of the light is greatly reduced, and the efficiency of injecting the light in the air into the micro-structure film layer 30 is improved.

Alternatively, the refractive index of the microstructured film layer 30 may be 1, 1.05, 1.1, 1.15, 1.2, 1.25, 1.3.

In the present embodiment, the difference in reflectivity at each position of the surface of the microstructure film layer 30 is less than 2%. The arrangement ensures that the surface of the microstructure film layer 30 has better consistency and the reflectivity difference of each position is smaller, so that the optical performance difference of the surface of the lens is smaller, and the imaging quality is ensured.

As shown in fig. 24, in the present embodiment, a transition layer 20 may be further included, the transition layer 20 is disposed between the microstructure film layer 30 and the lens, the transition layer 20 includes a first transition layer 21 and a second transition layer 22 which are stacked, and when the first transition layer 21 and the second transition layer 22 are plural, the first transition layer 21 and the second transition layer 22 are stacked alternately. The first transition layers 21 and the second transition layers 22 with different refractive indexes are alternately superposed, so that light can be deflected for many times in different refraction film layers in transmission, the reflectivity of the edge of the microstructure film layer 30 to the light is reduced, the transmittance of the light is increased, the relative illumination is increased, the vignetting phenomenon is reduced, and the optical consistency of each position of the microstructure film layer 30 is better.

By arranging the transition layer 20 between the microstructure film layer 30 and the lens, the requirement on the lens is greatly reduced, so that the lens can be better matched with the microstructure film layer 30, and the application range of the microstructure film layer 30 is greatly increased. The refractive indices of the first transition layer 21 and the second transition layer 22 are different, so that the light rays can be deflected at different angles when propagating in the first transition layer 21 and the second transition layer 22, so as to increase the uniformity of the light rays transmitted to the lens. Meanwhile, the reflectivity of the edge of the microstructure film layer 30 to light can be reduced, so that the transmittance of the light is increased, the relative illumination is increased, the vignetting phenomenon is reduced, and the working stability of the microstructure film layer is increased.

Specifically, the refractive index of the first transition layer 21 is 1.5 or more and 2.5 or less. This arrangement provides a higher refractive index for the first transition layer 21, so that light entering the first transition layer 21 can be deflected more, and the distribution of light reaching the lens is more uniform.

Alternatively, the refractive index of the first transition layer 21 may be 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5.

Specifically, the refractive index of the second transition layer 22 is 1.4 or more and 1.5 or less. Set up like this and make certain refractive index difference between second transition layer 22 and the first transition layer 21 for light is different at the deflection of second transition layer 22 and the deflection direction and the deflection angle in first transition layer 21, and then greatly increased the variety of light in the reflection reducing membrane system deflection, the reflection of the light that has significantly reduced makes the more even of the light distribution that reachs lens.

Several specific comparative examples are described below, and the following comparative examples one to four apply to example three. While comparative example five and comparative example six apply to example one and example two.

Comparative example 1

In comparative example one, as shown in fig. 4, the optical imaging system includes a first lens E1, the first lens E1 having a first lens object-side surface S1 and a first lens image-side surface S2; a second lens E2, the second lens E2 having a second lens object side surface S3 and a second lens image side surface S4; a third lens E3, the third lens E3 having an object-side surface S5 of the third lens and an image-side surface S6 of the third lens; a fourth lens E4, the fourth lens E4 having an object-side surface S7 of the fourth lens and an image-side surface S8 of the fourth lens; a fifth lens E5, the fifth lens E5 having an object-side surface S9 of the fifth lens and an image-side surface S10 of the fifth lens; filter E10, filter E10 has an object side S19 of the filter and an image side S20 of the filter, as well as a diaphragm STO and an image plane S21. In this example, a thin film structure is provided on the image side surface S2 of the second lens.

The control group was the PVD antireflection coating on the image-side surface S2 of the second lens, the experimental group was the microstructure film system on the image-side surface S2 of the second lens, and in this comparative example, the microstructure film system only included the microstructure film layer 30.

Table 1 shows the specific structure of the film layers of the control group and the experimental group in this comparative example.

TABLE 1

Fig. 5 shows the change of the reflectance curve at different incident angles of the control group in the present comparative example, and fig. 6 shows the change of the reflectance curve at different incident angles of the experimental group in the present comparative example. It can be seen that the control group has a large deviation (10% -30%) for normal incidence (0 °) and large-angle incidence (e.g. different from 10-40 °) due to the angle effect of the coating and the intrinsic angle effect in the subtraction principle. The microstructure film system containing the microstructure 31 in the experimental group can not only ensure that the reflectivity is far lower than that of a conventional film system, but also ensure that the reflectivity difference between normal incidence and large-angle incidence is within 2 percent. Because the incident angle of the light is different for the specific position of the aspheric lens, the reflectivity curve obtained by translating and rotating the lens to test the refractive index at different positions is consistent, and the reflectivity curve at different positions of the lens is not obviously different like PVD coating.

Comparative example No. two

In comparative example two, as shown in fig. 7, the optical imaging system includes a first lens E1, the first lens E1 having a first lens object-side surface S1 and a first lens image-side surface S2; a second lens E2, the second lens E2 having a second lens object side surface S3 and a second lens image side surface S4; a third lens E3, the third lens E3 having an object-side surface S5 of the third lens and an image-side surface S6 of the third lens; a fourth lens E4, the fourth lens E4 having an object-side surface S7 of the fourth lens and an image-side surface S8 of the fourth lens; a fifth lens E5, the fifth lens E5 having an object-side surface S9 of the fifth lens and an image-side surface S10 of the fifth lens; filter E10, filter E10 has an object side S19 of the filter and an image side S20 of the filter, as well as a diaphragm STO and an image plane S21. In this example, a thin-film structure is provided on the image-side surface S10 of the fifth lens.

The control group was formed by plating a PVD antireflection film on the image-side surface S10 of the fifth lens, the experimental group was formed by plating a microstructure film system on the image-side surface S10 of the fifth lens, and in this comparative example, the microstructure film system only included the microstructure film layer 30.

Table 2 shows the specific structure of the film layers of the control group and the experimental group in this comparative example.

TABLE 2

Fig. 8 shows the change of the reflectance curve at different incident angles of the control group in the present comparative example, and fig. 9 shows the change of the reflectance curve at different incident angles of the experimental group in the present comparative example. It can be seen that the control group has a large deviation (10% -30%) for normal incidence (0 °) and large-angle incidence (e.g. different from 10-40 °) due to the angle effect of the coating and the intrinsic angle effect in the subtraction principle. The microstructure film system containing the microstructure 31 in the experimental group can not only ensure that the reflectivity is far lower than that of a conventional film system, but also ensure that the reflectivity difference between normal incidence and large-angle incidence is within 2 percent. Because the incident angle of the light is different for the specific position of the aspheric lens, the reflectivity curve obtained by translating and rotating the lens to test the refractive index at different positions is consistent, and the reflectivity curve at different positions of the lens is not obviously different like PVD coating.

Comparative example No. three

In comparative example three, as shown in fig. 10, the optical imaging system includes a first lens E1, the first lens E1 having a first lens object-side surface S1 and a first lens image-side surface S2; a second lens E2, the second lens E2 having a second lens object side surface S3 and a second lens image side surface S4; a third lens E3, the third lens E3 having an object-side surface S5 of the third lens and an image-side surface S6 of the third lens; a fourth lens E4, the fourth lens E4 having an object-side surface S7 of the fourth lens and an image-side surface S8 of the fourth lens; a fifth lens E5, the fifth lens E5 having an object-side surface S9 of the fifth lens and an image-side surface S10 of the fifth lens; a sixth lens E6, the sixth lens E6 having a sixth lens object side surface S11 and a sixth lens image side surface S12; a seventh lens E7, the seventh lens E7 having an object-side surface S13 of the seventh lens and an image-side surface S14 of the seventh lens; filter E10, filter E10 has an object side S19 of the filter and an image side S20 of the filter, as well as a diaphragm STO and an image plane S21. In this example, a thin-film structure is provided on the image-side surface S12 of the sixth lens.

The control group is formed by plating a PVD antireflection film on the image side surface S12 of the sixth lens, the experimental group is formed by plating a microstructure film system on the image side surface S12 of the sixth lens, and in the present comparative example, the microstructure film system only includes the microstructure film layer 30.

Table 3 shows the specific structure of the film layers of the control group and the experimental group in this comparative example.

TABLE 3

Fig. 11 shows the change of the reflectance curve at different incident angles of the control group in the present comparative example, and fig. 12 shows the change of the reflectance curve at different incident angles of the experimental group in the present comparative example. It can be seen that the control group has a large deviation (10% -30%) for normal incidence (0 °) and large-angle incidence (e.g. different from 10-40 °) due to the angle effect of the coating and the intrinsic angle effect in the subtraction principle. The microstructure film system containing the microstructure 31 in the experimental group can not only ensure that the reflectivity is far lower than that of a conventional film system, but also ensure that the reflectivity difference between normal incidence and large-angle incidence is within 2 percent. Because the incident angle of the light is different for the specific position of the aspheric lens, the reflectivity curve obtained by translating and rotating the lens to test the refractive index at different positions is consistent, and the reflectivity curve at different positions of the lens is not obviously different like PVD coating.

Comparative example No. four

In comparative example four, as shown in fig. 13, the optical imaging system includes a first lens E1, the first lens E1 having a first lens object-side surface S1 and a first lens image-side surface S2; a second lens E2, the second lens E2 having a second lens object side surface S3 and a second lens image side surface S4; a third lens E3, the third lens E3 having an object-side surface S5 of the third lens and an image-side surface S6 of the third lens; a fourth lens E4, the fourth lens E4 having a fourth lens object side surface S7 and a fourth lens image side surface S8; a fifth lens E5, the fifth lens E5 having an object-side surface S9 of the fifth lens and an image-side surface S10 of the fifth lens; a sixth lens E6, the sixth lens E6 having an object-side surface S11 of the sixth lens and an image-side surface S12 of the sixth lens; a seventh lens E7, the seventh lens E7 having an object-side surface S13 of the seventh lens and an image-side surface S14 of the seventh lens; an eighth lens E8, the eighth lens E8 having an object-side surface S15 of the eighth lens and an image-side surface S16 of the eighth lens; filter E10, filter E10 has an object side S19 of the filter and an image side S20 of the filter, as well as a diaphragm STO and an image plane S21. In this example, a thin-film structure is provided on the image-side surface S4 of the second lens.

The control group was the PVD antireflection coating on the image-side surface S4 of the second lens, the experimental group was the microstructure film system on the image-side surface S4 of the second lens, and in this comparative example, the microstructure film system only included the microstructure film layer 30.

Table 4 shows the specific structure of the film layers of the control group and the experimental group in this comparative example.

TABLE 4

Fig. 14 shows the change of the reflectance curve at different incident angles of the control group in the present comparative example, and fig. 15 shows the change of the reflectance curve at different incident angles of the experimental group in the present comparative example. It can be seen that the control group has a large deviation (10% -30%) for normal incidence (0 °) and large-angle incidence (e.g. different from 10-40 °) due to the angle effect of the coating and the intrinsic angle effect in the subtraction principle. The microstructure film system containing the microstructure 31 in the experimental group can not only ensure that the reflectivity is far lower than that of a conventional film system, but also ensure that the reflectivity difference between normal incidence and large-angle incidence is within 2 percent. Because the incident angle of the light is different for the specific position of the aspheric lens, the reflectivity curve obtained by translating and rotating the lens to test the refractive index at different positions is consistent, and the reflectivity curve at different positions of the lens is not obviously different like PVD coating.

Comparative example five

In comparative example five, as shown in fig. 16, the optical imaging system includes a first lens E1, the first lens E1 having a first lens object-side surface S1 and a first lens image-side surface S2; a second lens E2, the second lens E2 having a second lens object side surface S3 and a second lens image side surface S4; a third lens E3, the third lens E3 having an object-side surface S5 of the third lens and an image-side surface S6 of the third lens; a fourth lens E4, the fourth lens E4 having an object-side surface S7 of the fourth lens and an image-side surface S8 of the fourth lens; a fifth lens E5, the fifth lens E5 having an object-side surface S9 of the fifth lens and an image-side surface S10 of the fifth lens; a sixth lens E6, the sixth lens E6 having an object-side surface S11 of the sixth lens and an image-side surface S12 of the sixth lens; filter E10, filter E10 has an object side S19 of the filter and an image side S20 of the filter, as well as a diaphragm STO and an image plane S21. In this example, a thin-film structure is provided on the object-side surface S5 of the third lens.

The control group was a PVD antireflection coating on the object-side surface S5 of the third lens, the experimental group was a microstructure film system on the object-side surface S5 of the third lens, and in this comparative example, the microstructure film system comprises a transition layer 20 and a microstructure film layer 30, wherein the first transition layer 21 is Al₂O₃The second transition layer 22 is SiO₂The microstructure film layer 30 is Al₂O₃。

Table 5 shows the specific structure of the film layers of the control group and the experimental group in this comparative example.

TABLE 5

Fig. 17 shows changes in reflectance curves at different incident angles of the control group in the present comparative example, and fig. 18 shows changes in reflectance curves at different incident angles of the experimental group in the present comparative example. It can be seen that the control group has a large deviation (10% -30%) for normal incidence (0 °) and large-angle incidence (e.g. different from 10-40 °) due to the angle effect of the coating and the intrinsic angle effect in the subtraction principle. The microstructure film system containing the microstructure 31 in the experimental group can not only ensure that the reflectivity is far lower than that of a conventional film system, but also ensure that the reflectivity difference between normal incidence and large-angle incidence is within 2 percent. Because the incident angle of the light is different for the specific position of the aspheric lens, the reflectivity curve obtained by translating and rotating the lens to test the refractive index at different positions is consistent, and the reflectivity curve at different positions of the lens is not obviously different like PVD coating.

Comparative example six

In comparative example six, as shown in fig. 19, the optical imaging system includes a first lens E1, the first lens E1 having a first lens object-side surface S1 and a first lens image-side surface S2; a second lens E2, the second lens E2 having a second lens object side surface S3 and a second lens image side surface S4; a third lens E3, the third lens E3 having an object-side surface S5 of the third lens and an image-side surface S6 of the third lens; a fourth lens E4, the fourth lens E4 having an object-side surface S7 of the fourth lens and an image-side surface S8 of the fourth lens; a fifth lens E5, the fifth lens E5 having an object-side surface S9 of the fifth lens and an image-side surface S10 of the fifth lens; a sixth lens E6, the sixth lens E6 having an object-side surface S11 of the sixth lens and an image-side surface S12 of the sixth lens; a seventh lens E7, the seventh lens E7 having an object-side surface S13 of the seventh lens and an image-side surface S14 of the seventh lens; an eighth lens E8, the eighth lens E8 having an object-side surface S15 of the eighth lens and an image-side surface S16 of the eighth lens; a ninth lens E9, the ninth lens E9 having an object-side surface S17 of the ninth lens and an image-side surface S18 of the ninth lens; filter E10, filter E10 has an object side S19 of the filter and an image side S20 of the filter, as well as a diaphragm STO and an image plane S21. In this example, a thin-film structure is provided on the object side S13 of the seventh lens.

The control group was formed by plating a PVD antireflection film on the object-side surface S13 of the seventh lens, and the experimental group was formed by plating a microstructure film system on the object-side surface S13 of the seventh lens. In this comparative example, the microstructured film system comprises a transition layer 20 and a microstructured film layer 30, wherein the first transition layer 21 is Al₂O₃The second transition layer 22 is SiO₂Micro, microThe structural film layer 30 is Al₂O₃Also in the present comparative example, the first transition layers 21 are two, and the second transition layers 22 are two and alternately stacked.

Table 6 shows the specific structure of the film layers of the control group and the experimental group in this comparative example.

TABLE 6

Fig. 20 shows the change of the reflectance curve at different incident angles of the control group in the present comparative example, and fig. 21 shows the change of the reflectance curve at different incident angles of the experimental group in the present comparative example. It can be seen that the control group has a large deviation (10% -30%) for normal incidence (0 °) and large-angle incidence (e.g. different from 10-40 °) due to the angle effect of the coating and the intrinsic angle effect in the subtraction principle. The microstructure film system containing the microstructure 31 in the experimental group can not only ensure that the reflectivity is far lower than that of a conventional film system, but also ensure that the reflectivity difference between normal incidence and large-angle incidence is within 2 percent. Because the incident angle of the light is different for the specific position of the aspheric lens, the reflectivity curve obtained by translating and rotating the lens to test the refractive index at different positions is consistent, and the reflectivity curve at different positions of the lens is not obviously different like PVD coating.

The normal incidence is an angle between the incident light and the normal of 0 °, and the large-angle incidence is an angle between the incident light and the normal of more than 10 ° and not more than 40 °.

It is to be understood that the above-described embodiments are only a few, and not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular is intended to include the plural unless the context clearly dictates otherwise, and it should be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of features, steps, operations, devices, components, and/or combinations thereof.

It should be noted that the terms "first," "second," and the like in the description and claims of this application and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the application described herein are capable of operation in sequences other than those illustrated or described herein.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An optical imaging lens, comprising:

a lens barrel;

the lens comprises a plurality of lenses which are arranged at intervals along the axial direction of the lens barrel;

a base layer (10);

a transition layer (20), one side surface of the transition layer (20) being connected with the substrate layer (10);

the microstructure film layer (30) is connected with the other side surface of the transition layer (20), the side surface, away from the base layer (10), of the microstructure film layer (30) is provided with a plurality of microstructures (31), and the refractive index of the microstructures (31) is gradually reduced towards the direction away from the lens.

2. Optical imaging lens according to claim 1, characterized in that the refractive index of the microstructure (31) is equal to or greater than 1 and equal to or less than 1.3.

3. Optical imaging lens according to claim 1, characterized in that the refractive index of the substrate layer (10) is equal to or greater than 1.4 and equal to or less than 1.7.

4. Optical imaging lens according to claim 1, characterized in that the material of the substrate layer (10) comprises one of APEL, EP, K9, K26R.

5. The optical imaging lens according to any one of claims 1 to 4, characterized in that the material of the microstructure film layer (30) is an inorganic dielectric material or an organic polymer.

6. Optical imaging lens according to any one of claims 1 to 4, characterized in that the material of the microstructured film layer (30) comprises AL₂O₃、CaO、CuO、Er₂O₃、Ga₂O₃、HfO₂、La₂O₃、MgO、Nb₂O₅、Sc₂O₃、SiO₂、Ta₂O₅、TiO₂、VXOY、Y₂O₃、Yb₂O₃、ZnO、ZrO₂、AlN、GaN、TaNX、TiAlN、TiNX、TaC、TiC、ZnS、SrS、CaF₂、LaF₃、MgF₂、SrF₂And a resin.

7. The optical imaging lens according to any one of claims 1 to 4,

the length of the microstructure (31) along the direction vertical to the base layer (10) is more than or equal to 10nm and less than or equal to 1000 nm; and/or

The length of the microstructure (31) along the direction parallel to the base layer (10) is greater than or equal to 10nm and less than or equal to 1000 nm.

8. Optical imaging lens according to any one of claims 1 to 4, characterized in that the cross-sectional area of the microstructure (31) in a direction parallel to the substrate layer (10) decreases gradually in a direction away from the substrate layer (10).

9. Optical imaging lens according to claim 8, characterized in that the microstructure (31) is triangular in cross section perpendicular to the base layer (10).

10. The optical imaging lens according to any one of claims 1 to 4,

the maximum reflectivity of the surface of the microstructure film layer (30) to light with the wavelength of 430nm to 780nm is less than or equal to 0.2%; and/or

The average reflectivity of the surface of the microstructure film layer (30) to light with the wavelength of 430nm to 780nm is less than or equal to 0.1 percent; and/or

The difference of the reflectivity of each position of the surface of the microstructure film layer (30) is less than 2%.