Micro single lens

Abstract

The invention 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 present invention relates to the technical field of optical lenses, and particularly to a mirrorless lens. Background Art

[0002] With the development of technology, the market demand for mirrorless cameras has been continuously expanding, and there are various demands for lenses with different focal lengths, different apertures, different focusing methods, and different prices. Compared with single-lens reflex cameras, mirrorless cameras have better portability. However, it is relatively difficult for existing mirrorless lenses to achieve fast autofocus, small distortion, and clear imaging. Summary of the Invention

[0003] The present invention provides a mirrorless lens that can meet the imaging requirements of high image quality and low distortion on the premise of ensuring low cost and small volume.

[0004] The present invention provides a mirrorless lens, which is characterized in that it includes 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 from the object plane to the image plane along the optical axis;

[0005] 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;

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

[0007] Optionally, the Abbe number of the third lens is Vd3; the Abbe number of the fourth lens is Vd4; where: 30 < Vd4 - Vd3 < 60.

[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 optical power of the first lens is Φ1, the optical power of the second lens is Φ2, the optical power of the third lens is Φ3, the optical power of the fourth lens is Φ4, the optical power of the fifth lens is Φ5, the optical power of the eighth lens is Φ8, the optical power of the ninth lens is Φ9, and the optical power of the mirrorless lens is Φ, where:

[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 optical power of the sixth lens is Φ6, the Abbe number of the sixth lens is Vd6, the optical power of the seventh lens is Φ7, the Abbe number of the seventh lens is Vd7, the optical power of the mirrorless lens is Φ, and the optical power of the cemented lens group formed by cementing the sixth lens and the seventh lens is Φ67, where:

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

[0014] Optionally, the semi-aperture of the first lens is SDmax, and the maximum image height of the mirrorless lens is H, where 0.68 < SDmax / H < 0.8.

[0015] Optionally, the distance from the optical axis center of the image side of the ninth lens to the image plane is BFL, and the focal length of the mirrorless lens is f, where: 0.38 < BFL / f < 0.46.

[0016] Optionally, the aperture number F of the mirrorless lens satisfies F ≤ 1.45.

[0017] Optionally, the mirrorless lens further includes a diaphragm;

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

[0019] The technical solution of the embodiment of the present invention provides a mirrorless lens including 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 the optical axis from the object plane to the 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 refractive index of the first lens is Nd1, where Nd1 > 1.9. By reasonably designing the relative positions and optical powers of the lenses, it is ensured that the mirrorless lens meets the imaging requirements of high image quality and low distortion under the conditions of small volume 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 present invention, nor is it used to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. Description of the Drawings

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the accompanying drawings required for the description of the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can be obtained based on these drawings.

[0022] Figure 1 Structural schematic diagram of a mirrorless camera lens provided in Embodiment 1 of the present invention;

[0023] Figure 2 MTF graph of a mirrorless camera lens provided in Embodiment 1 of the present invention;

[0024] Figure 3 Axial aberration curve graph of a mirrorless camera lens provided in Embodiment 1 of the present invention;

[0025] Figure 4 Field curvature and distortion curve graph of a mirrorless camera lens provided in Embodiment 1 of the present invention;

[0026] Figure 5 Structural schematic diagram of a mirrorless camera lens provided in Embodiment 2 of the present invention;

[0027] Figure 6 MTF graph of a mirrorless camera lens provided in Embodiment 2 of the present invention;

[0028] Figure 7 Axial aberration curve graph of a mirrorless camera lens provided in Embodiment 2 of the present invention;

[0029] Figure 8 Field curvature and distortion curve graph of a mirrorless camera lens provided in Embodiment 2 of the present invention;

[0030] Figure 9 Structural schematic diagram of a mirrorless camera lens provided in Embodiment 3 of the present invention;

[0031] Figure 10 MTF graph of a mirrorless camera lens provided in Embodiment 3 of the present invention;

[0032] Figure 11 Axial aberration curve graph of a mirrorless camera lens provided in Embodiment 3 of the present invention;

[0033] Figure 12 Field curvature and distortion curve graph of a mirrorless camera lens provided in Embodiment 3 of the present invention. Detailed implementation manners

[0034] To enable those skilled in the art to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without making creative efforts shall fall within the protection scope of the present invention.

[0035] It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily need to describe a specific order or sequence. It should be understood that such used data can be interchanged under appropriate circumstances so that the embodiments of the present invention described here can be implemented in an order different from those illustrated or described here. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device comprising a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0036] Figure 1 The following is a schematic structural diagram of a mirrorless camera lens provided in Embodiment 1 of the present invention. As Figure 1 shown, the mirrorless camera lens includes 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 first lens 101 has a positive optical power, the fifth lens 105 has a negative optical power, the eighth lens 108 has a positive optical power, and the ninth lens 109 has a negative optical power; the refractive index of the first lens 101 is Nd1, where Nd1 > 1.9.

[0037] Exemplarily, the optical power is equal to the difference between the convergence of the image-side light beam and the convergence of the object-side light beam, and it characterizes the ability of the optical system to deflect light rays. The greater the absolute value of the optical power, the stronger the bending ability of the light rays, and the smaller the absolute value of the optical power, the weaker the bending ability of the light rays. When the optical power is positive, the refraction of the light rays is convergent; when the optical power is negative, the refraction of the light rays is divergent. The optical power can be used to characterize a certain refracting surface of a lens (i.e., a surface of the lens), can be used to characterize a certain lens, or can be used to characterize a system formed by multiple lenses together (i.e., a lens group). In the mirrorless camera lens provided in this embodiment, each lens can be fixed to a lens barrel ( Figure 1Inside (not shown in the figure), the first lens 101 is set as a positive focal length lens, and the refractive index Nd1 of the first lens 101 satisfies Nd1 > 1.9, which is beneficial to controlling the light incident angle of the optical system, helping to relieve the large-angle light incident angle, reducing the aperture of the optical system, and thus reducing the volume and weight of the optical system. The fifth lens 105 is a lens with a negative focal length and can move along the optical axis to achieve focusing at different object distances, which is beneficial to reducing the weight of the focusing group and reducing the working pressure of the mechanical motor. Controlling the focal lengths of the eighth lens 108 and the ninth lens 109 can better correct the chromatic aberration of the lens, which is beneficial to improving the optical performance of the system. Reasonably distributing the focal lengths of each lens is beneficial to correcting the aberration at a large aperture and ensuring that the lens has a high resolution. 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 prepared from glass materials to better correct chromatic aberration and aberration and improve the image quality. The glass materials are various types of glass known to those skilled in the art, and the embodiments of the present invention will not elaborate or limit this.

[0038] The mirrorless camera lens provided by the embodiments of the present invention, by reasonably adjusting the number, relative position, and focal length of the lenses in the mirrorless camera lens, on the premise of low cost, ensures the balance of the incident angle sizes of the front and rear groups of lens elements of the mirrorless camera lens, reduces the sensitivity of the lens, ensures that the mirrorless camera lens has a high resolution, and thus realizes an optical lens capable of rapid autofocus, high image quality, and low distortion, meeting the usage requirements.

[0039] Optionally, the Abbe number of the third lens 103 is Vd3; the Abbe number of the fourth lens 104 is Vd4; wherein: 30 < Vd4 - Vd3 < 60. The Abbe number is an index used to represent the dispersion ability of a transparent medium. The more severe the medium dispersion, the smaller the Abbe number; conversely, the milder the medium dispersion, the larger the Abbe number. Thus, by matching and setting the Abbe numbers of the lenses in the mirrorless camera lens, it is beneficial to realizing the miniaturization of the mirrorless camera lens and can also exert the ability to correct the chromatic aberration of the optical system, thereby improving the resolution of the optical system.

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

[0041] Among them, the second lens 102, the third lens 103, and the fourth lens 104 can be set with different adhesive combination methods. Exemplarily, such as Figure 1As shown, the second lens 102 and the third lens 103 are adhesively fixed to form a doublet lens group, such as Figure 5 As shown, the second lens 102, the third lens 103 and the fourth lens 104 are adhesively fixed to form a doublet lens group, such as Figure 9 As shown, the third lens 103 and the fourth lens 104 are adhesively fixed to form a doublet lens group. By setting a doublet lens group or a triplet lens group in the mirrorless lens, the air gap between the second lens 102, the third lens 103 and the fourth lens 104 can be effectively reduced, thereby further reducing the overall length of the lens. In addition, the cemented lens group can minimize or eliminate chromatic aberration to such an extent that various aberrations of the mirrorless lens can be fully corrected. On the premise of a compact structure, the resolution can be improved, optical performances such as distortion can be optimized, the light loss caused by reflection between lenses can be reduced, the illuminance can be enhanced, thereby improving the image quality and enhancing the clarity of the lens imaging. In addition, the use of the cemented lens group can also reduce the assembling components between the lenses, simplify the assembly procedure in the lens manufacturing process, reduce the cost, and reduce the tolerance sensitivity problems such as tilt / eccentricity generated during the assembling process of the lens unit.

[0042] Optionally, the sixth lens 106 and the seventh lens 107 are adhesively fixed to form a cemented lens group.

[0043] Among them, by setting the sixth lens 106 and the seventh lens 107 to form a doublet lens group, the air gap between the sixth lens 106 and the seventh lens 107 can be effectively reduced, thereby further reducing the overall length of the lens. On the premise of a compact structure, the resolution can be improved, optical performances such as distortion can be optimized, the light loss caused by reflection between lenses can be reduced, the illuminance can be enhanced, thereby improving the image quality and enhancing the clarity of the lens imaging. The use of the doublet lens can also reduce the assembling components between the two lenses, simplify the assembly procedure in the lens manufacturing process, reduce the cost, and reduce the tolerance sensitivity problems such as tilt / eccentricity generated during the assembling process of the lens unit.

[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 mirrorless 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.

[0045] Among them, reasonably setting the optical power of the first lens 101 is beneficial to reducing the incident angle of light entering the optical system, narrowing the aperture of the optical system, thereby reducing the volume and weight of the optical system. According to the cemented combination method of the second lens 102, the third lens 103, and the fourth lens 104, reasonably setting the optical powers of the second lens 102, the third lens 103, and the fourth lens 104 can correct the chromatic aberration of the optical system, thereby improving the resolution of the optical system. The fifth lens 105 can move independently along the optical axis to achieve focusing on different object distances, thereby meeting the imaging requirements. Reasonably setting the ratios of the optical powers of the control eighth lens 108 and the ninth lens 109 to the optical power of the mirrorless camera lens respectively can better correct the chromatic aberration of the lens. Reasonably distributing the optical powers of each lens is beneficial to correcting the aberration at a large aperture and ensuring that the lens has a high resolution.

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

[0047] Among them, reasonably setting the optical powers and Abbe numbers of the sixth lens 106 and the seventh lens 107, and fixing and cementing the sixth lens 106 and the seventh lens 107 to form a doublet lens. Meeting the above conditions is beneficial for the doublet lens group to exert the ability to correct the chromatic aberration of the optical system, thereby improving the resolution of the optical system.

[0048] Optionally, the semi-aperture of the first lens 101 is SDmax, and the maximum image height of the mirrorless camera lens is H, where 0.68 < SDmax / H < 0.8. Meeting the above conditions is beneficial to reducing the volume and weight of the overall optical system, adapting to more usage environments, and reducing the material cost of the lens.

[0049] Optionally, the distance from the optical axis center of the image side of the ninth lens 109 to the image plane is BFL, and the focal length of the mirrorless camera lens is f, where: 0.38 < BFL / f < 0.46. Among them, the distance from the optical axis center of the image side of the ninth lens 109 to the image plane can be understood as the back focal length of the mirrorless camera lens. Meeting the above conditions can make the lens have an appropriate back focal length, improve the anti-distortion performance of the mirrorless camera lens, ensure the imaging quality of the mirrorless camera lens, and avoid interference between the lens and other components, reducing the assembly process difficulty of the lens.

[0050] Optionally, the aperture number F of the mirrorless camera lens satisfies F ≤ 1.45. The mirrorless camera lens provided by the embodiment of the present invention is a variable aperture lens, and the maximum aperture number is 1.45, which satisfies a large light throughput and is suitable for imaging requirements under low illuminance conditions.

[0051] Optionally, the mirrorless camera lens further includes a diaphragm STO; the diaphragm STO is located in the optical path between the fifth lens 105 and the sixth lens 106.

[0052] Among them, by adding a diaphragm STO, the propagation direction of the light beam can be adjusted, which is beneficial to improving the imaging quality. The diaphragm STO can be located in the optical path between the fifth lens 105 and the sixth lens 106, but the specific setting position of the diaphragm STO in the embodiment of the present invention is not limited.

[0053] Optionally, the mirrorless camera lens further includes a filter 10, and the filter 10 is located on the image side of the ninth lens 109. Among them, by providing a filter 10 on the image side of the ninth lens 109, unnecessary stray light can be filtered out, thereby improving the image quality of the optical lens. For example, by filtering out infrared light during the day through the filter 10, the imaging quality of the optical lens can be improved.

[0054] In summary, through reasonable selection of glass materials and reasonable distribution of lens focal power, refractive index, Abbe number, etc., an optical structure with nine lenses can enable the mirrorless camera lens provided by the embodiment of the present invention to achieve a lens focal length of about 55 mm, |optical distortion| < 1.7%, variable aperture and a maximum aperture number of 1.45 can be achieved, and automatic focusing can be performed for object distances from infinity to 365 mm. It has beneficial effects such as a compact structure, excellent imaging, and low cost.

[0055] The following further describes specific embodiments of the mirrorless camera lens applicable to the above embodiments with reference to the accompanying drawings.

[0056] Embodiment 1

[0057] Continuing to refer to Figure 1 , the mirrorless camera lens includes 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 glued and fixed to form a glued lens group, the sixth lens 106 and the seventh lens 107 are glued and fixed to form a glued lens group, and the diaphragm STO is located in the optical path between the fifth lens 105 and the sixth lens 106. Exemplarily, Table 1 details the specific optical physical parameters of each lens in the mirrorless camera lens provided by Embodiment 1 of the present invention in a feasible implementation manner.

[0058] Table 1 Design values of optical physical parameters of the mirrorless camera lens

[0059]

[0060]

[0061] The surface numbers in Table 1 are numbered according to the surface order of each lens. For example, "1" represents the object side of the first lens 101, "2" represents the image side of the first lens 101, and so on; "STO" represents the aperture of the lens; the radius of curvature represents the degree of curvature of the lens surface. A positive value indicates that the surface is bent towards the image side, and a negative value indicates that the surface is bent towards the object side. Among them, "Infinity" represents that the surface is a plane and the radius of curvature is infinite; the thickness represents the central axial distance from the current surface to the next surface, the refractive index represents the ability of the material between the current surface and the next surface to deflect light, and the space represents that the current position is air and the refractive index is 1.

[0062] The mirrorless lens of the first embodiment has reached the following technical indicators:

[0063] The focal length f is 56 mm; the aperture F is 1.45; the semi-image height is 28.4 mm; the object distance is infinity. The focusing interval thicknesses at different object distances in the first embodiment are shown in Table 2. T7 is the focusing interval thickness between the optical axis center of the image side of the fourth lens 104 and the optical axis center of the object side of the fifth lens 105, and T9 is the focusing interval thickness between the optical axis center of the image side of the fifth lens 105 and the aperture STO.

[0064] Table 2 Focusing Interval Thicknesses at Different Object Distances

[0065] Object distance T7 T9 3000mm 3.226mm 11.835mm 365mm 10.873mm 4.188mm

[0066] Furthermore, Figure 2 This is the MTF graph of a mirrorless lens provided in the first embodiment of the present invention. As Figure 2 shown, the transfer function is basically above 0.6 at 30 line pairs / mm in the MTF curve, which can meet the high image quality requirements.

[0067] Figure 3 This is the axial aberration curve graph of a mirrorless lens provided in the first embodiment of the present invention. As Figure 3As shown, the vertical direction represents the normalization of the aperture, 0 represents 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 mirrorless 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). The curves at different wavelengths are relatively concentrated, indicating that the axial aberration of this mirrorless lens at each wavelength is well controlled. Thus, it can be known that the mirrorless lens provided by the embodiment of the present invention can correct aberration well.

[0068] Figure 4 The following is the field curvature and distortion graph of a mirrorless lens provided by Embodiment 1 of the present invention. As Figure 4 shown, in the left coordinate system of the figure, the horizontal coordinate represents the magnitude of field curvature, in mm; the vertical coordinate represents the normalized image height, without unit; where T represents meridian and S represents sagittal; from Figure 4 it can be seen that for the light with a wavelength of 546 nm of the lens provided in this embodiment, the field curvature is effectively controlled, that is, when imaging, the image quality at the center and the image quality at the periphery have a small difference; in the right coordinate system, the horizontal coordinate represents the magnitude of distortion, in %; the vertical coordinate represents the normalized image height, without unit; from Figure 4 it can be seen that the imaging distortion of the lens provided in this embodiment is less than 2%, indicating that the distortion of this lens is well corrected and the difference between the image and the actual object is small.

[0069] Embodiment 2

[0070] Figure 5 The following is the structural schematic diagram of a mirrorless lens provided by Embodiment 2 of the present invention. As Figure 5 shown, the mirrorless lens includes 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 glued and fixed to form a glued lens group. The sixth lens 206 and the seventh lens 207 are glued and fixed to form a glued lens group. The aperture stop STO is located in the optical 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 mirrorless lens provided by Embodiment 2 of the present invention in a feasible implementation manner.

[0071] Table 3 Design values of the optical physical parameters of the mirrorless lens

[0072] Surface number Surface type Radius of curvature Thickness Refractive index Abbe number Semi-aperture Object surface Infinity Infinity Infinity 1 Standard surface 46.2439 5.753 1.9500 32.00 19.838 2 Standard surface 643.5165 0.398 19.000 3 Standard surface Infinity 0.000 19.206 4 Standard surface 38.9190 7.350 1.4900 81.00 17.304 5 Standard surface -111.0173 1.200 1.9000 31.00 16.352 6 Standard surface 35.2635 4.629 1.6000 64.00 14.692 7 Standard surface 186.6059 2.999(V) 14.200 8 Standard surface -167.9575 1.200 1.6800 31.00 12.612 9 Standard surface 27.5128 13.320(V) 11.839 STO Standard surface Infinity 2.133 11.998 11 Standard surface -575.2027 3.793 1.7000 29.00 12.052 12 Standard surface 34.5199 9.000 1.9500 32.00 12.205 13 Standard surface -46.9257 0.100 12.000 14 Standard surface 33.4620 5.627 1.880 39.00 12.404 15 Standard surface 1007.1393 1.012 11.941 16 Standard surface -119.6224 1.200 1.840 23.00 11.848 17 Standard surface 36.6924 21.485 11.538 18 Standard surface Infinity 2.000 1.520 64.10 14.141 19 Standard surface Infinity 1.000 14.314 Image surface Infinity 14.447

[0073] The surface numbers in Table 3 are numbered according to the surface order of each lens. For example, "1" represents the object side of the first lens 201, "2" represents the image side of the first lens 201, and so on; among them, "3" represents the surface number corresponding to the change in the focusing interval thickness of the fifth lens 205, and "STO" represents the aperture of the lens; the radius of curvature represents the degree of curvature of the lens surface. A positive value indicates that the surface bends towards the image side, and a negative value indicates that the surface bends towards the object side. Among them, "Infinity" indicates that the surface is a plane and the radius of curvature is infinite; the thickness represents the central axial distance from the current surface to the next surface, and the refractive index represents the ability of the material between the current surface and the next surface to deflect light. A space indicates that the current position is air and the refractive index is 1.

[0074] The mirrorless camera lens of the second embodiment has achieved the following technical specifications:

[0075] The focal length f is 54 mm; the aperture F is 1.45; the semi-image height is 28.4 mm; the object distance is infinity. The focusing interval thicknesses at 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 of the fourth lens 104 and the optical axis center of the object side of the fifth lens 205, and T9 is the focusing interval thickness between the optical axis center of the image side of the fifth lens 205 and the aperture STO.

[0076] Table 4 Focusing Interval Thicknesses at Different Object Distances

[0077] Object distance T7 T9 3000mm 3.925mm 12.394mm 365mm 11.535mm 4.7839mm

[0078] Furthermore, Figure 6 This is the MTF graph of a mirrorless camera lens provided in the second embodiment of the present invention. As Figure 6 shown, the transfer function at 30 line pairs / mm in the MTF curve is basically above 0.3, which can meet the high image quality requirements.

[0079] Figure 7 This is the axial aberration curve graph of a mirrorless camera lens provided in the second embodiment of the present invention. As Figure 7 shown, the vertical direction represents the normalization of the aperture, 0 represents on the optical axis, and the vertex in the vertical direction represents the maximum pupil radius; the horizontal direction represents the offset relative to the ideal focus, in millimeters (mm). The axial aberrations of this mirrorless camera lens at different wavelengths (0.436 μm, 0.486 μm, 0.546 μm, 0.588 μm, and 0.656 μm) are all controlled within the range of (-0.1 mm, +0.1 mm). The curves at different wavelengths are relatively concentrated, indicating that the axial aberrations of this mirrorless camera lens at each wavelength are well controlled. Thus, it can be known that the mirrorless camera lens provided in the embodiment of the present invention can correct aberrations well.

[0080] Figure 8This is the field curvature and distortion curve graph of a mirrorless lens provided in the second embodiment of the present invention. As Figure 8 shown, in the left coordinate system of the figure, the horizontal coordinate represents the magnitude of field curvature, with the unit of mm; the vertical coordinate represents the normalized image height, without a unit; where T represents the meridian and S represents the sagittal; from Figure 8 it can be seen that for the light with a wavelength of 546 nm in the lens provided in this embodiment, the field curvature is effectively controlled, that is, when imaging, the image quality difference between the center and the periphery is small; in the right coordinate system, the horizontal coordinate represents the magnitude of distortion, with the unit of %; the vertical coordinate represents the normalized image height, without a unit; from Figure 8 it can be seen that the imaging distortion of the lens provided in this embodiment is less than 2%, indicating that the distortion of the lens is well corrected and the difference between the image and the actual object is small.

[0081] Embodiment Three

[0082] Figure 9 This is the structural schematic diagram of a mirrorless lens provided in the third embodiment of the present invention. As Figure 9 shown, the mirrorless 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 in sequence along the optical axis from the object plane to the image plane. The third lens 303 and the fourth lens 304 are glued and fixed to form a glued lens group. The sixth lens 306 and the seventh lens 307 are glued and fixed to form a glued 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 and physical parameters of each lens in the mirrorless lens provided in the third embodiment of the present invention in a feasible implementation manner.

[0083] Table 5 Design values of the optical and physical parameters of the mirrorless lens

[0084]

[0085]

[0086] The surface numbers in Table 5 are numbered according to the surface order of each lens. For example, "1" represents the object side surface of the first lens, "2" represents the image side surface of the first lens 301, and so on; "STO" represents the aperture stop of the lens; the radius of curvature represents the degree of curvature of the lens surface. A positive value represents that the surface bends towards the image plane side, and a negative value represents that the surface bends towards the object plane side. Among them, "Infinity" represents that the surface is a plane and the radius of curvature is infinite; the thickness represents the central axial distance from the current surface to the next surface, and the refractive index represents the ability of the material between the current surface and the next surface to deflect light. A space represents that the current position is air and the refractive index is 1.

[0087] The mirrorless lens of this third embodiment has achieved the following technical specifications:

[0088] The focal length f is 55 mm; the aperture F is 1.45; the semi-image height is 28.4 mm; the object distance is infinity. The focusing interval thicknesses at different object distances in this third embodiment are shown in Table 6. 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 STO.

[0089] Table 6 Focusing Interval Thicknesses at Different Object Distances

[0090] Object distance T7 T9 3000mm 4.174mm 14.429mm 365mm 12.985mm 5.617mm

[0091] Furthermore, Figure 10 The MTF graph of a mirrorless lens provided for the third embodiment of the present invention is as Figure 10 shown. When the spatial frequency is 30 line pairs / mm in the MTF curve, the transfer function is basically above 0.4, which can meet the requirements of high image quality.

[0092] Figure 11 The axial aberration graph of a mirrorless lens provided for the third embodiment of the present invention is as Figure 11 shown. The vertical direction represents the normalization of the aperture, 0 represents on the optical axis, and the vertex in the vertical direction represents the maximum pupil radius; the horizontal direction represents the offset relative to the ideal focus, in millimeters (mm). The axial aberrations of this mirrorless lens at different wavelengths (0.436 μm, 0.486 μm, 0.546 μm, 0.588 μm, and 0.656 μm) are all controlled within the range of (-0.1 mm, +0.1 mm). The curves at different wavelengths are relatively concentrated, indicating that the axial aberrations of this mirrorless lens at each wavelength are well controlled. Thus, it can be seen that the mirrorless lens provided by the embodiment of the present invention can correct aberrations well.

[0093] Figure 12 The field curvature and distortion graph of a mirrorless lens provided for the third embodiment of the present invention is as Figure 12 shown. In the left coordinate system in the figure, the horizontal coordinate represents the magnitude of the field curvature, in mm; the vertical coordinate represents the normalized image height, without unit; where T represents meridian and S represents sagittal; Figure 12 It can be seen that for the light with a wavelength of 546 nm, the field curvature of the lens provided in this embodiment is effectively controlled, that is, when imaging, the image quality at the center and the periphery has a small difference; in the right coordinate system, the horizontal coordinate represents the magnitude of the distortion, in %; the vertical coordinate represents the normalized image height, without unit; Figure 12It can be seen that the imaging distortion of the lens provided in this embodiment is less than 1%, indicating that the distortion of the lens has been well corrected and the difference between the image and the actual object is small.

[0094] The above specific embodiments do not constitute a limitation to the protection scope of the present invention. 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 modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A micro single lens, characterized in that: It includes 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 arranged in sequence from the object plane to the image plane along the optical axis; The first lens has positive optical power, the fifth lens has negative optical power, the eighth lens has positive optical power, and the ninth lens has negative optical power; The refractive index of the first lens is Nd1, where Nd1>1.

9.

2. The micro single lens according to claim 1, characterized in that: The Abbe number of the third lens is Vd3; the Abbe number of the fourth lens is Vd4; wherein: 30 <Vd4-Vd3<60。 3. The micro single lens according to claim 1, characterized in that: 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.

4. The micro single lens according to claim 1, characterized in that: The sixth lens and the seventh lens are cemented and fixed to form a cemented lens group.

5. The micro single lens according to claim 1, characterized in that: 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: 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 single lens according to claim 1, characterized in that: The focal power of the sixth lens is Φ6, the Abbe number of the sixth lens is Vd6, the focal power of the seventh lens is Φ7, the Abbe number of the seventh lens 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 and the seventh lens being glued and fixed is Φ67, wherein: |100*(Φ6 / Vd6+Φ7 / Vd7)|<0.1; |Φ6+Φ7-Φ67|<0.

1.

7. The micro single lens according to claim 1, characterized in that: The semi-aperture of the first lens is SDmax, and the maximum image height of the micro-single lens is H, wherein 0.68 <SDmax / H<0.8。 8. The micro single lens according to claim 1, characterized in that: The distance from the center of the optical axis of the image side 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 single lens according to claim 1, characterized in that: The aperture number F of the micro single lens satisfies F≤1.

45.

10. The micro single lens according to claim 1, characterized in that: The micro single lens also includes an aperture; The aperture stop is located in an optical path between the fifth lens and the sixth lens.

Images