Micro single lens

Abstract

The utility model discloses a micro single lens. The micro single lens comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens and a ninth lens which are sequentially arranged from an object plane to an image plane along an optical axis, the first lens has positive focal power, the fifth lens has negative focal power, the eighth lens has positive focal power, and the ninth lens has negative focal power; the refractive index of the first lens is Nd1, and Nd1 is larger than 1.9. By reasonably designing the relative position and the focal power of the lens, the micro single lens is ensured to meet the imaging requirements of high image quality and low distortion under the conditions of small size and low cost.

Description

TECHNICAL FIELD

[0001] The utility model relates to optical lens technical field especially relates to a micro single lens. BACKGROUND

[0002] With the development of science and technology, the market demand of micro single camera expands unceasingly, and there are various demands for lenses with different focal lengths, different apertures, different focusing modes and different prices. Compared with single-lens reflex cameras, micro single cameras have better portability, but the existing micro single lenses are difficult to achieve fast automatic zoom and small distortion, and the imaging is clear. SUMMARY

[0003] The utility model provides a micro single lens under the premise of guaranteeing low cost, small size, satisfies high image quality, low distortion imaging demand.

[0004] The utility model provides a micro single lens, it is characterized in being including first lens, second lens, third lens, fourth lens, fifth lens, sixth lens, seventh lens, eighth lens, ninth lens that are arranged in order from object plane to image plane along optical axis,

[0005] The first lens has positive refractive power, the fifth lens has negative refractive power, the eighth lens has positive refractive power, and the ninth lens has negative refractive power.

[0006] The refractive index of the first lens is Nd1, wherein Nd1>1.9.

[0007] Optionally, the Abbe number of the third lens is Vd3, and the Abbe number of the fourth lens is Vd4, wherein 30

[0008] Optionally, the second lens and the third lens are glued and fixed to form a glued lens group, or the third lens and the fourth lens are glued and fixed to form a glued lens group, or the second lens, the third lens and the fourth lens are glued and fixed to form a glued lens group.

[0009] Optionally, the sixth lens and the seventh lens are glued and fixed to form a glued lens group.

[0010] Optionally, the focal power of the first lens is Φ1, the focal power of the second lens is Φ2, the focal power of the third lens is Φ3, the focal power of the fourth lens is Φ4, the focal power of the fifth lens is Φ5, the focal power of the eighth lens is Φ8, the focal power of the ninth lens is Φ9, and the focal power of the micro single lens is Φ, wherein:

[0011] 0.9<Φ1 / Φ<1.1; -0.2<Φ2 / Φ+Φ3 / Φ+Φ4 / Φ<0.1; -1.6<Φ5 / Φ<-1.3; 1.35<Φ8 / Φ<1.65; -2.2<Φ9 / Φ<-0.7.

[0012] Optionally, the sixth lens has an optical power Φ6 and an Abbe number Vd6, the seventh lens has an optical power Φ7 and an Abbe number Vd7, the micro single lens has an optical power Φ, and the sixth lens and the seventh lens are fixedly glued to form a glued lens group with an optical power Φ67, wherein:

[0013] |100*(Φ6 / Vd6+Φ7 / Vd7)|<0.1; |Φ6+Φ7-Φ67|<0.1.

[0014] Optionally, the first lens has a half aperture of SDmax, and the micro single lens has a maximum image height H, wherein 0.68<SDmax / H<0.8.

[0015] Optionally, the ninth lens has an image-side surface with an optical axis center to the image surface distance of BFL, and the micro single lens has a focal length f, wherein 0.38<BFL / f<0.46.

[0016] Optionally, the micro single lens has an aperture number F, and F satisfies F≤1.45.

[0017] Optionally, the micro single lens further comprises a diaphragm.

[0018] The diaphragm is located in an optical path between the fifth lens and the sixth lens.

[0019] The technical scheme of the embodiment of the utility model provides a micro single lens, which comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens and a ninth lens arranged in sequence along an optical axis from an object plane to an image plane; the first lens has a positive optical power, the fifth lens has a negative optical power, the eighth lens has a positive optical power, and the ninth lens has a negative optical power; the first lens has a refractive index of Nd1, wherein Nd1>1.9. By reasonably designing the relative positions and optical powers of the lenses, the micro single lens can meet the imaging requirements of high image quality and low distortion under the conditions of small size and low cost.

[0020] It should be understood that the content described in this part is not intended to identify the key or important features of the embodiments of the utility model, nor is it used to limit the scope of the utility model. Other features of the utility model will become easy to understand through the following description. BRIEF DESCRIPTION OF DRAWINGS

[0021] In order to more clearly illustrate the technical scheme in the embodiments of the present application, the drawings needed to be used in the embodiment description will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without any creative effort on the basis of these drawings.

[0022] Figure 1 A structural schematic diagram of a micro single lens provided by the first embodiment of the present application is shown in the figure.

[0023] Figure 2 An MTF diagram of the micro single lens provided by the first embodiment of the present application is shown in the figure.

[0024] Figure 3 An axial aberration curve diagram of the micro single lens provided by the first embodiment of the present application is shown in the figure.

[0025] Figure 4 A field curvature distortion curve diagram of the micro single lens provided by the first embodiment of the present application is shown in the figure.

[0026] Figure 5 A structural schematic diagram of a micro single lens provided by the second embodiment of the present application is shown in the figure.

[0027] Figure 6 An MTF diagram of the micro single lens provided by the second embodiment of the present application is shown in the figure.

[0028] Figure 7 An axial aberration curve diagram of the micro single lens provided by the second embodiment of the present application is shown in the figure.

[0029] Figure 8 A field curvature distortion curve diagram of the micro single lens provided by the second embodiment of the present application is shown in the figure.

[0030] Figure 9 A structural schematic diagram of a micro single lens provided by the third embodiment of the present application is shown in the figure.

[0031] Figure 10 An MTF diagram of the micro single lens provided by the third embodiment of the present application is shown in the figure.

[0032] Figure 11 An axial aberration curve diagram of the micro single lens provided by the third embodiment of the present application is shown in the figure.

[0033] Figure 12 A field curvature distortion curve diagram of the micro single lens provided by the third embodiment of the present application is shown in the figure. DETAILED DESCRIPTION

[0034] In order to make the person skilled in the art better understand the technical scheme of the present application, the technical scheme in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by the person skilled in the art without creative labor should belong to the scope of protection of the present application.

[0035] It should be noted that the terms "first", "second" and the like in the specification and claims of the present application and the above drawings are used to distinguish similar objects, and do not necessarily have to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device including a series of steps or units does not have to be limited to those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0036] Figure 1 A structural schematic diagram of a micro single lens provided for the embodiment of the present application is shown in Figure 1 The micro single lens includes first lens 101, second lens 102, third lens 103, fourth lens 104, fifth lens 105, sixth lens 106, seventh lens 107, eighth lens 108 and ninth lens 109 arranged in order along the optical axis from the object plane to the image plane. The first lens 101 has positive refractive power, the fifth lens 105 has negative refractive power, the eighth lens 108 has positive refractive power, and the ninth lens 109 has negative refractive power. The refractive index of the first lens 101 is Nd1, where Nd1>1.9.

[0037] For example, the focal power is equal to the difference between the converging degree of the image side beam and the converging degree of the object side beam, which represents the ability of the optical system to deflect light. The greater the absolute value of the focal power, the stronger the bending ability of the light, and the smaller the absolute value of the focal power, the weaker the bending ability of the light. When the focal power is positive, the refraction of the light is convergent; when the focal power is negative, the refraction of the light is divergent. The focal power can be used to represent a certain refractive surface of a lens (i.e. a surface of the lens), can be used to represent a certain lens, and can be used to represent a system (i.e. a lens group) formed by multiple lenses. In the micro single lens provided in the embodiment, each lens can be fixed in a lens barrel Figure 1The first lens 101 is arranged as a positive focal length lens in the optical system (not shown), the refractive index Nd1 of the first lens 101 satisfies Nd1>1.9, which is beneficial to control the light incidence angle of the optical system, help to alleviate the large angle of light incidence, reduce the aperture of the optical system, thereby reducing the volume and weight of the optical system. The fifth lens 105 is a negative focal length lens and can move along the optical axis to achieve focusing at different object distances, which is beneficial to reduce the weight of the focusing group and reduce the working pressure of the mechanical motor. Controlling the focal length of the eighth lens 108 and the focal length of the ninth lens 109 can better correct the chromatic aberration of the lens, which is beneficial to improve the optical performance of the system. Reasonably allocating the focal length of each lens is beneficial to the correction of aberration at a large aperture, and ensures that the lens has high resolving power. The first lens 101, the second lens 102, the third lens 103, the fourth lens 104, the fifth lens 105, the sixth lens 106, the seventh lens 107, the eighth lens 108 and the ninth lens 109 can all be made of glass material to better correct chromatic aberration and aberration and improve image quality. The glass material is various types of glass known to those skilled in the art, and the embodiments of the present application do not elaborate or limit them.

[0038] The micro single lens provided by the embodiment of the present application can reasonably adjust the number, relative position and focal length of the lenses in the micro single lens, ensure the balance of the incidence angle of the front and rear group lenses of the micro single lens under the premise of low cost, reduce the sensitivity of the lens, ensure that the micro single lens has high resolving power, and thus realize an optical lens with fast automatic focusing, high image quality and low distortion, thereby meeting the use requirements.

[0039] Optionally, the Abbe number of the third lens 103 is Vd3, and the Abbe number of the fourth lens 104 is Vd4, and 30<Vd4-Vd3<60. The Abbe number is an index used to represent the dispersion ability of a transparent medium. The more serious the dispersion of the medium is, the smaller the Abbe number is. Conversely, the lighter the dispersion of the medium is, the larger the Abbe number is. In this way, by matching the Abbe numbers of the lenses in the micro single lens, the micro single lens can be miniaturized, and the ability to correct the chromatic aberration of the optical system can be exerted, thereby improving the resolving power of the optical system.

[0040] Optionally, the second lens 102 and the third lens 103 are glued and fixed to form a glued lens group, or the third lens 103 and the fourth lens 104 are glued and fixed to form a glued lens group, or the second lens 102, the third lens 103 and the fourth lens 104 are glued and fixed to form a glued lens group.

[0041] The second lens 102, the third lens 103 and the fourth lens 104 can be arranged in different glued combinations, for example, Figure 1As shown, the second lens 102 and the third lens 103 are fixedly glued to form a double-glued lens group, as shown in Figure 5 As shown, the second lens 102, the third lens 103 and the fourth lens 104 are fixedly glued to form a double-glued lens group, as shown in Figure 9 As shown, the third lens 103 and the fourth lens 104 are fixedly glued to form a double-glued lens group. By arranging the double-glued lens group or the three-lens group in the micro single lens, the air gap between the second lens 102, the third lens 103 and the fourth lens 104 can be effectively reduced, so as to further reduce the total length of the lens. In addition, the glued lens group can maximize the reduction or elimination of chromatic aberration, so that various aberrations of the micro single lens can be fully corrected, the resolution can be improved, the optical performance such as distortion can be optimized, the light loss caused by the reflection between the lenses can be reduced, the illumination can be improved, and thus the image quality and the clarity of the lens imaging can be improved. In addition, the use of the glued lens group can also reduce the assembly components between the lenses, simplify the assembly process in the lens manufacturing process, reduce the cost, and reduce the tolerance sensitivity problems such as tilt and eccentricity of the lens unit caused in the assembly process.

[0042] Optionally, the sixth lens 106 and the seventh lens 107 are fixedly glued to form a glued lens group.

[0043] Optionally, the sixth lens 106 and the seventh lens 107 are fixedly glued to form a glued lens group.

[0044] Optionally, the optical power of the first lens 101 is Φ1, the optical power of the second lens 102 is Φ2, the optical power of the third lens 103 is Φ3, the optical power of the fourth lens 104 is Φ4, the optical power of the fifth lens 105 is Φ5, the optical power of the eighth lens 108 is Φ8, the optical power of the ninth lens 109 is Φ9, and the optical power of the micro single lens is Φ, wherein: 0.9<Φ1 / Φ<1.1; -0.2<Φ2 / Φ+Φ3 / Φ+Φ4 / Φ<0.1; -1.6<Φ5 / Φ<-1.3; 1.35<Φ8 / Φ<1.65; -2.2<Φ9 / Φ<-0.7.

[0045] The reasonable setting of the focal power of the first lens 101 is beneficial to reduce the incidence angle of the light entering the optical system, reduce the aperture of the optical system, and thus reduce the volume and weight of the optical system. According to the cementing combination mode of the second lens 102, the third lens 103 and the fourth lens 104, the reasonable setting of the focal power of the second lens 102, the third lens 103 and the fourth lens 104 plays a role in correcting the chromatic aberration of the optical system, thereby improving the resolving power of the optical system. The fifth lens 105 can be moved alone along the optical axis to focus to different object distances, thereby meeting the imaging requirements. Reasonable setting of the ratio of the focal power of the eighth lens 108 and the ninth lens 109 to the focal power of the micro single lens can better correct the chromatic aberration of the lens. Reasonable allocation of the focal power of each lens is beneficial to the correction of aberration at a large aperture, and ensures that the lens has high resolving power.

[0046] Optionally, the focal power of the sixth lens 106 is Φ6, the Abbe number of the sixth lens 106 is Vd6, the focal power of the seventh lens 107 is Φ7, the Abbe number of the seventh lens 107 is Vd7, the focal power of the micro single lens is Φ, and the focal power of the cemented lens group formed by the sixth lens 106 and the seventh lens 107 is Φ67, wherein: |100*(Φ6 / Vd6+Φ7 / Vd7)|<0.1; |Φ6+Φ7-Φ67|<0.1.

[0047] Optionally, the focal power of the sixth lens 106 is Φ6, the Abbe number of the sixth lens 106 is Vd6, the focal power of the seventh lens 107 is Φ7, the Abbe number of the seventh lens 107 is Vd7, the focal power of the micro single lens is Φ, and the focal power of the cemented lens group formed by the sixth lens 106 and the seventh lens 107 is Φ67, wherein: |100*(Φ6 / Vd6+Φ7 / Vd7)|<0.1; |Φ6+Φ7-Φ67|<0.1.

[0048] Optionally, the half aperture of the first lens 101 is SDmax, and the maximum image height of the micro single lens is H, wherein 0.68<SDmax / H<0.8. Meeting the above conditions is beneficial to reduce the volume and weight of the overall optical system, adapt to more use environments, and reduce the material cost of the lens.

[0049] Optionally, the distance from the optical axis center of the image side surface of the ninth lens 109 to the image surface is BFL, and the focal length of the micro single lens is f, wherein 0.38<BFL / f<0.46. The distance from the optical axis center of the image side surface of the ninth lens 109 to the image surface can be understood as the back focal length of the micro single lens. Meeting the above conditions can make the lens have a suitable back focal length, improve the distortion resistance of the micro single lens, ensure the imaging quality of the micro single lens, avoid interference between the lens and other elements, and reduce the assembly process difficulty of the lens.

[0050] Optionally, the aperture number F of the micro single lens satisfies F≤1.45. The micro single lens provided in the embodiment of the utility model is a variable aperture lens, the maximum aperture number is 1.45, the light passing amount is large, and the imaging requirement under low illumination condition is met.

[0051] Optionally, the micro single lens further comprises a diaphragm STO; the diaphragm STO is located in the light path between the fifth lens 105 and the sixth lens 106.

[0052] The diaphragm STO can be located in the light path between the fifth lens 105 and the sixth lens 106, but the specific setting position of the diaphragm STO is not limited in the embodiment of the utility model.

[0053] Optionally, the micro single lens further comprises a filter 10, and the filter 10 is located on the image side of the ninth lens 109. By setting the filter 10 on the image side of the ninth lens 109, the unwanted stray light can be filtered out, so that the image quality of the optical lens is improved. For example, the imaging quality of the optical lens is improved by filtering out infrared light in the daytime through the filter 10.

[0054] By reasonably selecting the glass material and reasonably distributing the lens focal length, refractive index, Abbe number and the like, the optical structure of the nine lenses can make the micro single lens provided in the embodiment of the utility model realize the following beneficial effects: the lens focal length is about 55mm, |optical distortion|<1.7%, the aperture is variable, the maximum aperture number is 1.45, the working object distance can be automatically focused from infinity to 365mm, the structure is excellent, the imaging is excellent, the cost is low, and the like.

[0055] The specific embodiments of the micro single lens applicable to the above embodiments will be further described below with reference to the accompanying drawings.

[0056] Embodiment one

[0057] Continuously referring to Figure 1 The micro single lens comprises a first lens 101, a second lens 102, a third lens 103, a fourth lens 104, a fifth lens 105, a sixth lens 106, a seventh lens 107, an eighth lens 108 and a ninth lens 109 arranged in sequence along the optical axis from the object plane to the image plane, the second lens 102 and the third lens 103 are fixedly glued to form a glued lens group, the sixth lens 106 and the seventh lens 107 are fixedly glued to form a glued lens group, and the diaphragm STO is located in the light path between the fifth lens 105 and the sixth lens 106. For example, Table 1 details the specific optical physical parameters of each lens in the micro single lens provided in the embodiment one of the utility model in a feasible embodiment.

[0058] Table 1: Design values of optical-physical parameters of the micro single lens

[0059] Surface No. Surface Type Radius of Curvature Thickness Refractive Index Abbe Number Half Aperture Object Plane Infinity Infinity Infinity 1 Standard Plane 45.8645 6.840 1.9500 32.00 21.396 2 Standard Plane 195.1424 0.593 20.000 3 Standard Plane 27.4790 8.224 1.4900 81.00 17.513 4 Standard Plane 1118.5036 1.200 1.7200 28.00 16.369 5 Standard Plane 20.8915 1.572 13.558 6 Standard Plane 27.8235 4.424 1.5900 68.00 13.538 7 Standard Plane 145.4310 2.320(V) 13.000 8 Standard Plane 285.4614 1.200 1.6200 46.00 11.843 9 Standard Plane 23.7380 12.741(V) 10.827 STO Standard Plane Infinity 4.385 9.639 11 Standard Plane -21.8898 1.857 1.6500 33.00 9.617 12 Standard Plane 31.9973 8.647 1.8800 39.00 10.740 13 Standard Plane -31.9706 0.100 11.220 14 Standard Plane 55.3854 5.943 1.880 39.00 12.286 15 Standard Plane -66.6984 1.746 12.400 16 Standard Plane -34.7987 1.200 1.810 24.00 12.328 17 Standard Plane -80.3975 19.007 12.611 18 Standard Plane Infinity 2.000 1.520 64.10 14.171 19 Standard Plane Infinity 1.000 14.272 Image Plane Infinity 14.350

[0060] The surface number in Table 1 is numbered according to the surface order of each lens, for example, "1" represents the object side surface of the first lens 101, "2" represents the image side surface of the first lens 101, and so on; "STO" represents the diaphragm of the lens; the radius of curvature represents the bending degree of the lens surface, a positive value represents that the surface is bent to the image side, and a negative value represents that the surface is bent to the object side, wherein "Infinity" represents that the surface is a plane, and the radius of curvature is infinite; the thickness represents the center axis distance from the current surface to the next surface; the refractive index represents the deflection ability of the material between the current surface and the next surface; and the space represents that the current position is air, and the refractive index is 1.

[0061] The micro single lens of the first embodiment achieves the following technical indicators:

[0062] The focal length f is 56mm; the aperture F is 1.45; the half image height is 28.4mm; and the object distance is infinite. The focusing interval thickness under different object distances in the first embodiment is shown in Table 2. T7 is the focusing interval thickness between the optical axis center of the image side surface of the fourth lens 104 and the optical axis center of the object side surface of the fifth lens 105, and T9 is the focusing interval thickness between the optical axis center of the image side surface of the fifth lens 105 and the diaphragm STO.

[0063] Table 2: Focusing interval thickness under different object distances

[0064] Object Distance T7 T9 3000 mm 3.226 mm 11.835 mm 365 mm 10.873 mm 4.188 mm

[0065] Further, Figure 2 The MTF graph of the micro single lens provided by the first embodiment of the utility model is shown in FIG. 3. Figure 2 As shown in FIG. 3, the transfer function in the 30 line pairs / mm in the MTF curve is basically above 0.6, which can meet the high image quality requirement.

[0066] Figure 3 The axial aberration curve graph of the micro single lens provided by the first embodiment of the utility model is shown in FIG. 4. Figure 3As shown, the vertical direction represents the normalized aperture, 0 represents on the optical axis, and the vertical direction vertex represents the maximum pupil radius; the horizontal direction represents the offset relative to the ideal focal point, with units of millimeters (mm). The axial aberration of the micro single lens at different wavelengths (0.436 μm, 0.486 μm, 0.546 μm, 0.588 μm and 0.656 μm) is controlled within the range of (-0.1 mm, +0.1 mm), and the curves of different wavelengths are relatively concentrated, indicating that the axial aberration of the micro single lens at each wavelength is well controlled, so it can be known that the micro single lens provided by the embodiment of the utility model can better correct aberration.

[0067] Figure 4 A field curvature distortion curve of the micro single lens provided by the embodiment one of the utility model is shown in the figure. Figure 4 As shown in the left coordinate system in the figure, the horizontal coordinate represents the size of the field curvature, with units of mm; the vertical coordinate represents the normalized image height, without units; wherein T represents the meridian, and S represents the arc loss; from Figure 4 It can be seen that the lens provided by the embodiment effectively controls the light with a wavelength of 546 nm on the field curvature, that is, the difference between the central image quality and the peripheral image quality is small during imaging; in the right coordinate system, the horizontal coordinate represents the size of the distortion, with units of %; the vertical coordinate represents the normalized image height, without units; from Figure 4 It can be seen that the imaging distortion of the lens provided by the embodiment is less than 2%, indicating that the lens distortion is well corrected, and the difference between the image and the actual object is small.

[0068] Embodiment two

[0069] Figure 5 A structure schematic view of the micro single lens provided by the embodiment two of the utility model is shown in the figure. Figure 5 As shown, the micro single lens comprises a first lens 201, a second lens 202, a third lens 203, a fourth lens 204, a fifth lens 205, a sixth lens 206, a seventh lens 207, an eighth lens 208 and a ninth lens 209 arranged in sequence along the optical axis from the object plane to the image plane, the second lens 202, the third lens 203 and the fourth lens 204 are fixedly glued to form a glued lens group, the sixth lens 206 and the seventh lens 207 are fixedly glued to form a glued lens group, and the diaphragm STO is located in the light path between the fifth lens 205 and the sixth lens 206. Exemplarily, Table 3 details the specific optical physical parameters of each lens in the micro single lens provided by the embodiment two of the utility model in a feasible implementation manner.

[0070] Table 3 Design values of optical physical parameters of the micro single lens

[0071] Surface No. Surface Type Radius of Curvature Thickness Refractive Index Abbe Number Half Aperture Object Plane Infinity Infinity Infinity 1 Standard Plane 46.2439 5.753 1.9500 32.00 19.838 2 Standard Plane 643.5165 0.398 19.000 3 Standard Plane Infinity 0.000 19.206 4 Standard Plane 38.9190 7.350 1.4900 81.00 17.304 5 Standard Plane -111.0173 1.200 1.9000 31.00 16.352 6 Standard Plane 35.2635 4.629 1.6000 64.00 14.692 7 Standard Plane 186.6059 2.999(V) 14.200 8 Standard Plane -167.9575 1.200 1.6800 31.00 12.612 9 Standard Plane 27.5128 13.320(V) 11.839 STO Standard Plane Infinity 2.133 11.998 11 Standard Plane -575.2027 3.793 1.7000 29.00 12.052 12 Standard Plane 34.5199 9.000 1.9500 32.00 12.205 13 Standard Plane -46.9257 0.100 12.000 14 Standard Plane 33.4620 5.627 1.880 39.00 12.404 15 Standard Plane 1007.1393 1.012 11.941 16 Standard Plane -119.6224 1.200 1.840 23.00 11.848 17 Standard Plane 36.6924 21.485 11.538 18 Standard Plane Infinity 2.000 1.520 64.10 14.141 19 Standard Plane Infinity 1.000 14.314 Image Plane Infinity 14.447

[0072] The surface sequence number in Table 3 is numbered according to the surface sequence of each lens, for example, "1" represents the object side surface of the first lens 201, "2" represents the image side surface of the first lens 201, and so on; wherein "3" represents the surface sequence number of the focusing interval thickness of the fifth lens 205, and "STO" represents the diaphragm of the lens; the radius of curvature represents the bending degree of the lens surface, the positive value represents that the surface is bent to the image side, and the negative value represents that the surface is bent to the object side, wherein "Infinity" represents that the surface is a plane, and the radius of curvature is infinite; the thickness represents the center axis distance from the current surface to the next surface, the refractive index represents the deflection ability of the material between the current surface and the next surface to the light, and the space represents that the current position is empty, and the refractive index is 1.

[0073] The micro single lens of the second embodiment of the present application achieves the following technical indicators:

[0074] The focal length f is 54mm; the aperture F is 1.45; the half image height is 28.4mm; and the object distance is infinite. The focusing interval thicknesses of different object distances in the second embodiment are shown in Table 4. T7 is the focusing interval thickness between the optical axis center of the image side surface of the fourth lens 104 and the optical axis center of the object side surface of the fifth lens 205, and T9 is the focusing interval thickness between the optical axis center of the image side surface of the fifth lens 205 and the diaphragm STO.

[0075] Table 4: Focusing interval thicknesses of different object distances

[0076] Object Distance T7 T9 3000 mm 3.925 mm 12.394 mm 365 mm 11.535 mm 4.7839 mm

[0077] Further, Figure 6 The MTF graph of the micro single lens provided by the second embodiment of the present application is shown in FIG. 6, and the MTF curve is shown in FIG. 7. Figure 6 As shown in FIG. 7, the transfer function of the 30 line pairs / mm in the MTF curve is basically above 0.3, which can meet the high image quality requirement.

[0078] Figure 7 The axial aberration curve graph of the micro single lens provided by the second embodiment of the present application is shown in FIG. 8, and the axial aberration curve is shown in FIG. 9. Figure 7 As shown in FIG. 9, the vertical direction represents the normalization of the aperture, 0 represents on the optical axis, and the vertical direction vertex represents the maximum pupil radius; the horizontal direction represents the offset amount relative to the ideal focus point, and the unit is millimeter (mm). The axial aberrations of the micro single lens under different wavelengths (0.436μm, 0.486μm, 0.546μm, 0.588μm and 0.656μm) are all controlled within the range of (-0.1mm, +0.1mm), and the different wavelength curves are relatively concentrated, which indicates that the axial aberrations of the micro single lens at each wavelength are well controlled, so it can be known that the micro single lens provided by the second embodiment of the present application can well correct the aberration.

[0079] Figure 8A field curvature distortion curve of a micro-lens provided in Embodiment 2 of this utility model, as shown in... Figure 8 As shown, in the coordinate system on the left side of the figure, the horizontal coordinate represents the magnitude of the field curvature, in mm; the vertical coordinate represents the normalized image height, which has no unit; where T represents the meridion and S represents the arc loss; from Figure 8 It can be seen that the lens provided in this embodiment effectively controls the field curvature of light with a wavelength of 546nm, meaning that during imaging, the difference in image quality between the center and the periphery is small; in the coordinate system on the right, the horizontal axis represents the magnitude of distortion, expressed as a percentage; the vertical axis represents the normalized image height, which has no unit; from Figure 8 As can be seen, the imaging distortion of the lens provided in this embodiment is less than 2%, indicating that the lens distortion has been well corrected and the difference between the image and the actual object is small.

[0080] Example 3

[0081] Figure 9 This is a schematic diagram of the structure of a micro-lens provided in Embodiment 3 of this utility model, as shown below. Figure 9 As shown, the micro-lens includes a first lens 301, a second lens 302, a third lens 303, a fourth lens 304, a fifth lens 305, a sixth lens 306, a seventh lens 307, an eighth lens 308, and a ninth lens 309 arranged sequentially along the optical axis from the object plane to the image plane. The third lens 303 and the fourth lens 304 are cemented together to form a cemented lens group, and the sixth lens 306 and the seventh lens 307 are also cemented together to form a cemented lens group. The aperture stop STO is located in the optical path between the fifth lens 305 and the sixth lens 306. Exemplarily, Table 5 details the specific optical physical parameters of each lens in the micro-lens provided in Embodiment 3 of this utility model, using a feasible implementation method.

[0082] Table 5 Design values ​​of optical physical parameters for mirrorless lenses

[0083]

[0084]

[0085] The surface numbers in Table 5 are assigned according to the surface order of each lens. For example, "1" represents the object side of the first lens, "2" represents the image side of the first lens 301, and so on. "STO" represents the aperture stop of the lens. The radius of curvature represents the curvature of the lens surface. A positive value means that the surface bends towards the image plane, and a negative value means that the surface bends towards the object plane. "Infinity" means that the surface is flat and the radius of curvature is infinite. The thickness represents the central axial distance between the current surface and the next surface. The refractive index represents the ability of the material between the current surface and the next surface to deflect light. A blank space means that the current position is air and the refractive index is 1.

[0086] The mirrorless lens in this third embodiment achieves the following technical specifications:

[0087] The focal length f is 55mm; the aperture F is 1.45; the half-image height is 28.4mm; and the object distance is infinity. Table 6 shows the focusing interval thickness at different object distances in this embodiment three. T7 is the focusing interval thickness between the optical axis center of the image side of the fourth lens 304 and the optical axis center of the object side of the fifth lens 305, and T9 is the focusing interval thickness between the optical axis center of the image side of the fifth lens 305 and the aperture stop STO.

[0088] Table 6 Focusing Interval Thickness at Different Object Distances

[0089] Object Distance T7 T9 3000 mm 4.174 mm 14.429 mm 365 mm 12.985 mm 5.617 mm

[0090] Furthermore, Figure 10 An MTF chart of a micro-lens provided in Embodiment 3 of this utility model is shown below. Figure 10 As shown, the transfer function in the MTF curve at 30 line pairs / mm is generally above 0.4, which can meet the requirements for high image quality.

[0091] Figure 11 An axial aberration curve of a micro-lens provided in Embodiment 3 of this utility model is shown below. Figure 11 As shown, the vertical direction represents the normalized aperture, 0 indicates on the optical axis, and the vertical vertex represents the maximum pupil radius; the horizontal direction represents the offset relative to the ideal focus, in millimeters (mm). The axial aberration of this micro-lens is controlled within the range of (-0.1mm, +0.1mm) at different wavelengths (0.436μm, 0.486μm, 0.546μm, 0.588μm, and 0.656μm). The curves for different wavelengths are relatively concentrated, indicating that the axial aberration of this micro-lens is well controlled at each wavelength. Therefore, it can be seen that the micro-lens provided by this embodiment can effectively correct aberrations.

[0092] Figure 12 A field curvature distortion curve of a micro-lens provided in Embodiment 3 of this utility model, as shown in... Figure 12 As shown, in the coordinate system on the left side of the figure, the horizontal coordinate represents the magnitude of the field curvature, in mm; the vertical coordinate represents the normalized image height, which has no unit; where T represents the meridion and S represents the arc loss; from Figure 12 It can be seen that the lens provided in this embodiment effectively controls the field curvature of light with a wavelength of 546nm, meaning that during imaging, the difference in image quality between the center and the periphery is small; in the coordinate system on the right, the horizontal axis represents the magnitude of distortion, expressed as a percentage; the vertical axis represents the normalized image height, which has no unit; from Figure 12It can be seen that the imaging distortion of the lens provided by the embodiment is less than 1%, which indicates that the lens distortion is well corrected, and the difference between the image and the actual object is small.

[0093] The specific embodiments described above do not constitute a limitation on the protection scope of the utility model. Those skilled in the art should understand that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the utility model should be included in the protection scope of the utility model.

Claims

1. A micro single lens characterized by, The first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens, the eighth lens and the ninth lens are arranged in sequence along the optical axis from the object plane to the image plane. The first lens has positive refractive power, the fifth lens has negative refractive power, the eighth lens has positive refractive power, and the ninth lens has negative refractive power. The refractive index of the first lens is Nd1, where Nd1>1.

9.

2. The micro lens of claim 1, wherein, The Abbe number of the third lens is Vd3, and the Abbe number of the fourth lens is Vd4, where 30<Vd4-Vd3<60.

3. The micro lens of claim 1, wherein, The second lens and the third lens are fixedly bonded to form a bonded lens group, or the third lens and the fourth lens are fixedly bonded to form a bonded lens group, or the second lens, the third lens and the fourth lens are fixedly bonded to form a bonded lens group.

4. The micro lens of claim 1, wherein, The sixth lens and the seventh lens are fixedly bonded to form a bonded lens group.

5. The micro lens of claim 1, wherein, The refractive power of the first lens is Φ1, the refractive power of the second lens is Φ2, the refractive power of the third lens is Φ3, the refractive power of the fourth lens is Φ4, the refractive power of the fifth lens is Φ5, the refractive power of the eighth lens is Φ8, the refractive power of the ninth lens is Φ9, and the refractive power of the micro single lens is Φ, where: 0.9<Φ1 / Φ<1.1; -0.2<Φ2 / Φ+Φ3 / Φ+Φ4 / Φ<0.1; -1.6<Φ5 / Φ<-1.3; 1.35<Φ8 / Φ<1.65; -2.2<Φ9 / Φ<-0.

7.

6. The micro lens of claim 1, wherein, The refractive power of the sixth lens is Φ6, the Abbe number of the sixth lens is Vd6, the refractive power of the seventh lens is Φ7, the Abbe number of the seventh lens is Vd7, the refractive power of the micro single lens is Φ, and the refractive power of the bonded lens group formed by the fixed bonding of the sixth lens and the seventh lens is Φ67, where: |100*(Φ6 / Vd6+Φ7 / Vd7)|<0.1; |Φ6+Φ7-Φ67|<0.

1.

7. The micro lens of claim 1, wherein, The half aperture of the first lens is SDmax, and the maximum image height of the micro single lens is H, where 0.68<SDmax / H<0.

8.

8. The micro lens of claim 1, wherein, The distance from the optical axis center of the image side surface of the ninth lens to the image plane is BFL, and the focal length of the micro single lens is f, where 0.38<BFL / f<0.

46.

9. The micro lens of claim 1, wherein, The aperture number F of the micro single lens satisfies F≤1.

45.

10. The micro lens of claim 1, wherein, The micro single lens further comprises a diaphragm. The diaphragm is located in the optical path between the fifth lens and the sixth lens.

Images