Sammer lens

Abstract

The utility model discloses a Sammer 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, a ninth lens and a tenth lens which are sequentially arranged along an optical axis from an object plane to an image plane, the first lens has negative focal power, the second lens has positive focal power, and the tenth lens has negative focal power. The third lens has negative focal power, the fourth lens has positive focal power, the fifth lens has negative focal power, the sixth lens has negative focal power, the seventh lens has positive focal power, the eighth lens has negative focal power, the ninth lens has positive focal power, the tenth lens has positive focal power, and all the lenses are glass spherical lenses. According to the embodiment of the utility model, the 10 spherical lenses are adopted, the focal power of each lens is reasonably distributed, and the spherical lenses with low cost are used to realize the small size, low distortion, low field curvature, large inclination angle and high-quality imaging.

Description

Technical Field

[0001] This utility model relates to the field of optical technology, and in particular to a SAM lens. Background Technology

[0002] With technological advancements, the application potential of SAM lenses is being continuously explored in more fields, especially in applications requiring high-precision imaging and depth information, such as autonomous driving, robot vision, marine exploration, and industrial inspection, where their application prospects are broad. According to SAM's law, when the extensions of the image plane, lens plane, and object plane intersect on a single line, a clear image of the entire field of view of a tilted target can be achieved.

[0003] However, the design and manufacturing process of SAM lenses is quite complex, especially in terms of correcting image distortion, which requires highly precise calibration and adjustment. This complexity stems from the fact that SAM lenses need to maintain image sharpness when shooting at an angle, while using a calibration plate to establish a mapping relationship between the tilted image and the corrected image in order to eliminate distortion and restore the true image.

[0004] To correct field curvature and distortion and achieve higher tilt imaging quality, existing SAM lenses use aspherical lenses to correct aberrations in the edge field of view, which greatly increases costs. Utility Model Content

[0005] This invention provides a Sham lens that achieves large tilt angle, low distortion, low field curvature, and high-quality imaging using a low-cost spherical lens.

[0006] This utility model provides a SAM lens, comprising a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens, a ninth lens, and a tenth lens arranged sequentially along the optical axis from the object plane to the image plane;

[0007] The first lens has negative optical power, the second lens has positive optical power, the third lens has negative optical power, the fourth lens has positive optical power, the fifth lens has negative optical power, the sixth lens has negative optical power, the seventh lens has positive optical power, the eighth lens has negative optical power, the ninth lens has positive optical power, and the tenth lens has positive optical power.

[0008] The first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens, the eighth lens, the ninth lens, and the tenth lens are all glass spherical lenses.

[0009] Optionally, the Sham lens also includes an aperture stop;

[0010] The aperture is located in the optical path between the fifth lens and the sixth lens.

[0011] Optionally, the total optical power of the first lens, the second lens, the third lens, the fourth lens and the fifth lens is ΦZ1, and the total optical power of the sixth lens, the seventh lens and the eighth lens is ΦZ2, where -0.6400≤ΦZ1 / ΦZ2≤-0.4300.

[0012] Optionally, the optical power of the first lens is ΦL1, the optical power of the second lens is ΦL2, and -2.5500≤ΦL2 / ΦL1≤-2.2400.

[0013] Optionally, the refractive index of the first lens is Nd1, and the refractive index of the second lens is Nd2, where 1.0900≤Nd2 / Nd1≤1.1100.

[0014] Optionally, the refractive index of the ninth lens is Nd9, and the refractive index of the eighth lens is Nd8, where 1.1000≤Nd9 / Nd8≤1.1400.

[0015] Optionally, the shape factor of the sixth lens is Ω6, and the shape factor of the seventh lens is Ω7, where 6.48000≤MIN.|Ω6, Ω7|≤7.0900.

[0016] Optionally, the Abbe number of the third lens is Vd3, and the Abbe number of the fourth lens is Vd4, where 1.23000 ≤ Vd4 / Vd3.

[0017] Optionally, the SAM lens further includes a front plate glass and a rear plate glass, the front plate glass being located on the object side of the first lens and the rear plate glass being located on the image side of the tenth lens.

[0018] Optionally, the distance from the object side to the image plane of the front flat glass is TTL, and the half-image height of the SAM lens is IM, where 5.1300≤TTL / IM≤5.1500.

[0019] The Sham lens provided in this embodiment employs 10 spherical lenses. By rationally allocating the optical power of each lens, the Sham lens can support an object distance of 217mm, an object plane tilt angle of up to 62°, and an image plane tilt angle ranging from 16.75° to 17.09° within the working wavelength range of 390μm to 420μm. The distortion is ≤0.66%, the total optical length is ≤59.19mm, the 50pl / mm for upright imaging is >0.79MTF, and the 50pl / mm for tilted imaging is >0.67MTF. Thus, a Sham lens that balances small size, low distortion, low field curvature, large tilt angle, and high-quality imaging is achieved using relatively low-cost spherical lenses.

[0020] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of this utility model, nor is it intended to limit the scope of this utility model. Other features of this utility model will become readily apparent from the following description. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 A schematic diagram of the structure of a Sham lens provided in an embodiment of this utility model;

[0023] Figure 2 A schematic diagram of the optical path of a Sham lens during positive imaging, provided for an embodiment of this utility model;

[0024] Figure 3 A schematic diagram of the optical path of a Sham lens during tilt imaging, provided for an embodiment of this utility model;

[0025] Figure 4 This is a schematic diagram of another Sham lens provided in an embodiment of the present invention;

[0026] Figure 5 Another schematic diagram of the optical path of a Sham lens in positive imaging provided for an embodiment of this utility model;

[0027] Figure 6 Another schematic diagram of the optical path of a Sham lens during tilt imaging, provided as an embodiment of this utility model;

[0028] Figure 7 A schematic diagram of the structure of another Sham lens provided in this embodiment of the present utility model;

[0029] Figure 8 A schematic diagram of the optical path of a Sham lens during positive imaging, provided as an embodiment of this utility model;

[0030] Figure 9 A schematic diagram of the optical path of a Sham lens during tilt imaging, provided as an embodiment of this utility model;

[0031] Figure 10 This is a fan-shaped diagram of the Sham lens provided in Embodiment 1 of this utility model;

[0032] Figure 11 The field curvature distortion curve of the Schahm lens provided in Embodiment 1 of this utility model;

[0033] Figure 12 The positive imaging MTF curve of the Sham lens provided in Embodiment 1 of this utility model;

[0034] Figure 13 The oblique imaging MTF curve of the Sham lens provided in Embodiment 1 of this utility model;

[0035] Figure 14 This is a fan-shaped diagram of the Sham lens provided in Embodiment 2 of this utility model;

[0036] Figure 15 The field curvature distortion curve of the Sham lens provided in Embodiment 2 of this utility model;

[0037] Figure 16 The positive imaging MTF curve of the Sham lens provided in Embodiment 2 of this utility model;

[0038] Figure 17 The oblique imaging MTF curve of the Sham lens provided in Embodiment 2 of this utility model;

[0039] Figure 18 This is the optical fan diagram of the Sham lens provided in Embodiment 3 of this utility model;

[0040] Figure 19 The field curvature distortion curve of the Sham lens provided in Embodiment 3 of this utility model;

[0041] Figure 20 The positive imaging MTF curve of the Sham lens provided in Embodiment 3 of this utility model;

[0042] Figure 21 The oblique imaging MTF curve of the Sham lens provided in Embodiment 3 of this utility model. Detailed Implementation

[0043] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0044] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this utility model are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the utility model described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0045] Figure 1 This is a schematic diagram of the structure of a Sham lens provided in an embodiment of the present invention. Figure 2 A schematic diagram of the optical path of a Sham lens during positive imaging is provided for an embodiment of this utility model. Figure 3 A schematic diagram of the optical path of a Sham lens during tilted imaging is provided as an embodiment of this utility model. Figure 4 This is a schematic diagram of another Sham lens provided in an embodiment of the present invention. Figure 5 This is another schematic diagram of the optical path of a Sham lens during positive imaging, provided as an embodiment of the present invention. Figure 6 This is another schematic diagram of the optical path of a Sham lens during tilted imaging, provided as an embodiment of the present invention. Figure 7 This is a schematic diagram of another Sham lens provided in an embodiment of the present utility model. Figure 8 This is another schematic diagram of the optical path of a Sham lens during positive imaging, provided by an embodiment of the present invention. Figure 9 A schematic diagram of the optical path of another Sham lens during tilted imaging, as provided in this embodiment of the present invention, is shown below. Figures 1-9 As shown, the SAM lens provided in this embodiment of the present invention includes a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7, an eighth lens L8, a ninth lens L9, and a tenth lens L10 arranged sequentially along the optical axis from the object plane to the image plane.

[0046] The first lens L1 has negative optical power, the second lens L2 has positive optical power, the third lens L3 has negative optical power, the fourth lens L4 has positive optical power, the fifth lens L5 has negative optical power, the sixth lens L6 has negative optical power, the seventh lens L7 has positive optical power, the eighth lens L8 has negative optical power, the ninth lens L9 has positive optical power, and the tenth lens L10 has positive optical power.

[0047] Lens L1, L2, L3, L4, L5, L6, L7, L8, L9, and L10 are all glass spherical lenses.

[0048] The SAM lens (also called a tilt-shift lens) provided in the utility model embodiment can be used as an industrial lens in 2D or 3D inspection, and is suitable for the inspection needs of narrow areas in three-dimensional space, but is not limited thereto.

[0049] Among them, the manufacturing process of spherical lenses is relatively simple, with high production efficiency and low cost. Compared with aspherical lenses, spherical lenses do not require complex processing equipment and processes. Therefore, the use of spherical lenses for the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6, the seventh lens L7, the eighth lens L8, the ninth lens L9, and the tenth lens L10 can significantly reduce manufacturing costs.

[0050] Meanwhile, glass lenses possess excellent thermal and chemical stability, making them less susceptible to the effects of environmental factors such as temperature and humidity. The use of glass lenses in lenses L1, L2, L3, L4, L5, L6, L7, L8, L9, and L10 ensures consistent optical performance over long-term use. Furthermore, by appropriately selecting the refractive index and Abbe number of the glass lenses, chromatic aberration can be effectively reduced, ensuring the authenticity and accuracy of the image colors.

[0051] Furthermore, optical power is equal to the difference between the convergence of the image-side beam and the convergence of the object-side beam; it characterizes the ability of an optical system to deflect light rays. The larger the absolute value of the optical power, the stronger the bending ability of light rays; the smaller the absolute value, the weaker the bending ability. When the optical power is positive, the refraction of light rays is converging; when the optical power is negative, the refraction of light rays is diverging. Optical power can be used to characterize a single refractive surface of a lens (i.e., one surface of the lens), a single lens, or a system formed by multiple lenses (i.e., a lens group).

[0052] In this embodiment of the invention, the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6, the seventh lens L7, the eighth lens L8, the ninth lens L9, and the tenth lens L10 are configured with a negative-positive-negative-positive-negative-negative-positive-positive optical power combination to rationally allocate the optical power of each lens. Since the Sham lens can be used in scenarios where both the object plane and the image plane are tilted, the combination of more positive and negative lenses corrects the field curvature of the system, ultimately making the Sham lens more effective. The SAM lens supports an object distance of 217mm within the operating wavelength range of 390μm to 420μm, an object plane tilt angle of up to 62°, an image plane tilt angle ranging from 16.75° to 17.09°, |distortion| ≤ 0.66%, a total optical length ≤ 59.19mm, and a 50pl / mm > 0.79MTF for upright imaging and a 50pl / mm > 0.67MTF for tilted imaging. Thus, the SAM lens achieves a balance of small size, low distortion, low field curvature, large tilt angle, and high-quality imaging using a relatively low-cost spherical lens.

[0053] As one feasible implementation, the optical power of the first lens L1 is Φ1, the optical power of the second lens L2 is Φ2, the optical power of the third lens L3 is Φ3, the optical power of the fourth lens L4 is Φ4, the optical power of the fifth lens L5 is Φ5, the optical power of the sixth lens L6 is Φ6, the optical power of the seventh lens L7 is Φ7, the optical power of the eighth lens L8 is Φ8, the optical power of the ninth lens L9 is Φ9, and the optical power of the tenth lens L10 is Φ10.

[0054] -0.0300≤Φ1≤-0.0200;0.0500≤Φ2≤0.0600;

[0055] -0.0200≤Φ3≤-0.0100;0.0400≤Φ4≤0.0500;

[0056] -0.0700≤Φ5≤-0.0600;-0.0300≤Φ6≤-0.0200;

[0057] 0.0001≤Φ7≤0.0200;-0.0400≤Φ8≤-0.0200;

[0058] 0.0300≤Φ9≤0.0500;0.0100≤Φ10≤0.0300;

[0059] By further limiting the optical power of the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6, the seventh lens L7, the eighth lens L8, the ninth lens L9, and the tenth lens L10, the optical power of the entire SAM lens is controlled to be distributed in a certain proportion. While achieving the above-mentioned beneficial effects, the balance of the incident angle of the front and rear lenses can be ensured, the sensitivity of the lenses can be reduced, the system aberration can be corrected, and the imaging quality can be improved.

[0060] As a possible implementation method, such as Figures 1-9 As shown, the SAM lens also includes an aperture stop STO, which is located in the optical path between the fifth lens L5 and the sixth lens L6.

[0061] The STO has five lenses on one side of its object side, and five lenses on the other side of its object side. By placing the STO in the middle of the SAM lens, an approximately symmetrical optical structure can be formed around the STO. This symmetrical structure can effectively correct lens distortion, reduce aberrations in the edge field of view, and ensure that there is no significant distortion in the edge image at different tilt angles.

[0062] As a feasible implementation, the total optical power of the first lens L1, the second lens L2, the third lens L3, the fourth lens L4 and the fifth lens L5 is ΦZ1, and the total optical power of the sixth lens L6, the seventh lens L7 and the eighth lens L8 is ΦZ2, with -0.6400≤ΦZ1 / ΦZ2≤-0.4300.

[0063] In this embodiment, by rationally allocating the optical power of the five lenses before and after the aperture stop, the optical power of the two sets of lenses before and after the aperture stop are opposite and their absolute values ​​are close, which can effectively control the lens distortion. Among them, the maximum distortion value of the SAM lens is MAX.DISG, and |MAX.DISG|≤0.6600%, which can reduce the aberration of the edge field of view and ensure that there is no obvious distortion at the edge of the image under different tilt angles.

[0064] As a feasible implementation, the optical power of the first lens L1 is ΦL1, the optical power of the second lens L2 is ΦL2, and -2.5500≤ΦL2 / ΦL1≤-2.2400.

[0065] In this embodiment, the first lens L1 and the second lens L2 are located at the front end of the SAM lens. By setting the optical power ΦL1 of the first lens L1 and the optical power ΦL2 of the second lens L2 to satisfy -2.5500≤ΦL2 / ΦL1≤-2.2400, the first lens L1 and the second lens L2 can meet the design of a negative optical power lens and a positive optical power lens. Moreover, the optical power of the first lens L1 and the second lens L2 differs greatly, and the interval between the first lens L1 and the second lens L2 is small, which can effectively correct spherical aberration and improve the imaging quality of the SAM lens during detection.

[0066] As a feasible implementation, the refractive index of the first lens L1 is Nd1, the refractive index of the second lens L2 is Nd2, and 1.0900≤Nd2 / Nd1≤1.1100.

[0067] By setting the refractive index Nd1 of the first lens L1 and the refractive index Nd2 of the second lens L2 to satisfy 1.0900≤Nd2 / Nd1≤1.1100, the refractive indices of the first lens L1 and the second lens L2 can be made to differ significantly, and the distance between the first lens L1 and the second lens L2 can be made smaller. This can effectively correct spherical aberration and improve the imaging quality of the SAM lens during testing.

[0068] As a feasible implementation, the refractive index of the ninth lens L9 is Nd9, the refractive index of the eighth lens L8 is Nd8, and 1.1000≤Nd9 / Nd8≤1.1400.

[0069] The ninth lens L9 and the eighth lens L8 are located at the rear end of the Sham lens. By setting the refractive index Nd9 of the ninth lens L9 and the refractive index Nd8 of the eighth lens L8 to satisfy 1.1000≤Nd9 / Nd8≤1.1400, the ninth lens L9 and the eighth lens L8 are respectively high-refractive-index positive lenses and low-refractive-index negative lenses. This allows for the bending of edge light at a shorter distance and more efficient correction of field curvature, thereby reducing the overall size of the lens.

[0070] As a feasible implementation, the shape factor of the sixth lens L6 is Ω6, and the shape factor of the seventh lens L7 is Ω7, with 6.48000≤MIN.|Ω6, Ω7|≤7.0900.

[0071] Among them, the shape factor, as a parameter affecting the basic optical performance of a lens, can be adjusted by changing the curvature, aperture, and material of the lens, thereby optimizing the focusing ability and imaging quality of the optical system.

[0072] In this embodiment, MIN.|Ω6,Ω7| represents the minimum of the absolute values ​​of the shape factor Ω6 of the sixth lens L6 and the shape factor Ω7 of the seventh lens L7.

[0073] By setting the shape factor Ω6 of the sixth lens L6 and the shape factor Ω7 of the seventh lens L7 to satisfy 6.48000≤MIN.|Ω6|, Ω7|≤7.0900, aberrations can be corrected more effectively and image quality can be improved.

[0074] As a feasible implementation, the Abbe number of the third lens L3 is Vd3, the Abbe number of the fourth lens L4 is Vd4, and 1.23000≤Vd4 / Vd3.

[0075] In this embodiment, the third lens L3 and the fourth lens L4 are relatively close to the aperture stop. The third lens L3 and the fourth lens L4 form a negative and positive lens group. By setting the Abbe number Vd3 of the third lens L3 and the Abbe number Vd4 of the fourth lens L4 to satisfy 1.23000≤Vd4 / Vd3, the Abbe numbers of the third lens L3 and the fourth lens L4 are significantly different, which can effectively correct the chromatic aberration of the system and improve the imaging quality. When the SAM lens is used for inspection, the inspection effect can be clearer and more accurate.

[0076] As a possible implementation method, such as Figures 1-9 As shown, the SAM lens also includes a front plate glass CG1 and a rear plate glass CG2. The front plate glass CG1 is located on the object side of the first lens L1, and the rear plate glass CG2 is located on the image side of the tenth lens L10.

[0077] Both the front flat glass CG1 and the rear flat glass CG2 can serve to filter light or provide protection.

[0078] For example, the front-facing flat glass CG1 can effectively block stray light from the external environment from entering the lens, reducing ghosting and glare, and improving image clarity and contrast, but it is not limited to this.

[0079] The rear flat glass CG2 can be directly installed in front of the image sensor to prevent dust, moisture or other contaminants from entering the sensor area, thus protecting the sensor and extending the life of the device, but it is not limited to this.

[0080] As a feasible implementation, the distance from the object side to the image plane of the front flat glass CG1 is TTL, the half-image height of the SAM lens is IM, and 5.1300≤TTL / IM≤5.1500.

[0081] TTL can be understood as the total optical length of a SAM lens. In other words, while keeping the image height constant, the shorter the total optical length, the smaller the corresponding size of the SAM lens.

[0082] In this embodiment, the distance TTL from the object side to the image plane of the front flat glass CG1 and the half-image height IM of the SAM lens satisfy 5.1300≤TTL / IM≤5.1500, which can reduce the volume while achieving a large image height, making the SAM lens more flexible for application in various environments.

[0083] As a feasible implementation method, TTL≤59.19mm makes the SAM lens have a shorter overall optical length, a compact structure, and a small size, making it easy to install in various devices, especially in space-constrained environments, and allowing for more flexible application in a variety of environments.

[0084] As a feasible implementation method, the focal length of the SAM lens is EFL, 35.5500≤EFL≤35.9100. In industrial inspection, the SAM lens can provide sufficient magnification and resolution within the above focal length range to capture minute defects or features, while maintaining a large working distance for easy operation.

[0085] As a feasible implementation, 16.7500≤θ≤17.0900, where θ is the tilt angle of the image plane when the Sham lens is used for oblique imaging.

[0086] Understandably, the larger the image plane tilt angle, the more pronounced the field curvature and astigmatism become, requiring more lenses for correction. Therefore, it is difficult for Sham lenses with large tilt angles to balance the image quality of upright and oblique imaging.

[0087] In this embodiment, controlling θ within the range of 16.7500≤θ≤17.0900 can provide high-quality imaging at large tilt angles, ensuring the clarity and resolution of the edge image. At the same time, a reasonable tilt angle can effectively reduce aberrations caused by the tilt of the object surface, enabling the SAM lens to provide more accurate and realistic images under complex imaging conditions (such as narrow spaces).

[0088] Furthermore, by appropriately setting the tilt angle θ of the image plane, the convergence path of light can be optimized, the size of the blur spot on the image plane can be reduced, thereby improving the modulation transfer function (MTF) performance. In particular, at 50 line pairs / mm (lp / mm) from the center field of view to the edge field of view, the MTF value of the SAM lens is higher than 0.78MTF (orthogonal imaging) and 0.67MTF (oblique imaging), demonstrating excellent resolving power.

[0089] The following describes a specific embodiment of the Sham lens applicable to the above-described embodiments, with reference to the accompanying drawings.

[0090] Example 1

[0091] Continue to refer to Figures 1-3 The SAM lens provided in Embodiment 1 of this utility model includes a front flat glass CG1, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, an aperture STO, a sixth lens L6, a seventh lens L7, an eighth lens L8, a ninth lens L9, a tenth lens L10, and a rear flat glass CG2 arranged sequentially along the optical axis from the object plane to the image plane.

[0092] Table 1 details the surface type, radius of curvature, thickness, material (refractive index / Abbe number), and half-aperture of each lens in the Sham lens provided in Embodiment 1, according to a feasible implementation method. The Sham lenses in Table 1 correspond to... Figures 1-3 The Sham lens shown.

[0093] Table 1 Design values ​​of optical physical parameters for Sham lenses

[0094]

[0095]

[0096] The surface numbers in Table 1 are assigned according to the surface sequence of each lens; where "1" represents the object-side surface of the first lens, "2" represents the image-side surface of the first lens, and so on; the radius of curvature represents the degree of curvature of the lens surface, with a positive value indicating that the surface bends towards the image plane and a negative value indicating that the surface bends towards the object plane; 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, with a blank space indicating that the current position is air and the refractive index is 1; the Abbe number represents the dispersion characteristics of the material between the current surface and the next surface. Half-aperture indicates half the aperture size of the current surface. When the interval between the 24 surfaces is 9.814 mm, clear alignment is possible when the object plane is tilted at 62°, and the image plane tilt angle is 16.7576°.

[0097] Figure 10 The image shown is a fan plot of a Schahm lens provided in Embodiment 1 of this utility model. The fan plot is one of the most commonly used evaluation methods in modern optical design. In this plot, the horizontal axis represents the beam aperture, and the vertical axis represents the transverse aberration. The ideal curve is a straight line coinciding with the horizontal axis, indicating that all light rays converge at the same point on the image plane. The interval corresponding to the vertical axis of the curve represents the maximum dispersion range of the beam on the ideal image plane. The fan plot can reflect not only monochromatic aberrations of different wavelengths but also the magnitude of transverse chromatic aberration. Figure 10It can be seen that the SAM lens closely approximates the horizontal axis at all wavelengths in all fields of view, indicating that the transverse aberration of each wavelength of the SAM lens is well corrected. At the same time, there is no obvious dispersion of each wavelength, indicating that the chromatic aberration of the SAM lens is also well corrected, thus ensuring that the SAM lens can meet the requirements of high-resolution imaging.

[0098] Figure 11 The field curvature distortion curve of the Sham lens provided in Embodiment 1 of this utility model is shown in the coordinate system on the left side of the figure. The horizontal axis represents the magnitude of the field curvature in mm; the vertical axis represents the normalized image height, which has no unit; where T represents the meridion and S represents the sagitta; Figure 11 It can be seen that the lens provided in this embodiment effectively controls field curvature, meaning that during imaging, the difference in image quality between the center and the periphery is small, resulting in good consistency. 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 11 As can be seen, the distortion of the lens provided in this embodiment has been well corrected, with optical distortion less than ±0.66%.

[0099] Figure 12 The MTF curve of the positive imaging of the Sham lens provided in Embodiment 1 of this utility model is as follows: Figure 12 As shown, the lens provided in this embodiment has an image quality of 50pl / mm from the center field of view to the edge field of view that is higher than 0.78MTF when imaging in positive mode, and the imaging has excellent resolution.

[0100] Figure 13 The oblique imaging MTF curve of the Sham lens provided in Embodiment 1 of this utility model is as follows: Figure 13 As shown, the lens provided in this embodiment has an image quality of 50pl / mm from the center field of view to the edge field of view that is higher than 0.67MTF when imaging at an angle, and the imaging has excellent resolution.

[0101] Example 2

[0102] Continue to refer to Figures 4-6 The SAM lens provided in Embodiment 2 of this utility model includes a front flat glass CG1, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, an aperture STO, a sixth lens L6, a seventh lens L7, an eighth lens L8, a ninth lens L9, a tenth lens L10 and a rear flat glass CG2 arranged sequentially along the optical axis from the object plane to the image plane.

[0103] Table 2 details the surface type, radius of curvature, thickness, material (refractive index / Abbe number), and half-aperture of each lens in the Sham lens provided in Example 2, according to a feasible implementation method. The Sham lenses in Table 1 correspond to... Figures 4-6 The Sham lens shown.

[0104] Table 2 Design values ​​of optical physical parameters for Sham lenses

[0105]

[0106]

[0107] The surface numbers in Table 2 are assigned according to the surface sequence of each lens; where "1" represents the object-side surface of the first lens, "2" represents the image-side surface of the first lens, and so on; the radius of curvature represents the degree of curvature of the lens surface, with a positive value indicating that the surface bends towards the image plane and a negative value indicating that the surface bends towards the object plane; 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, with a blank space indicating that the current position is air and the refractive index is 1; the Abbe number represents the dispersion characteristics of the material between the current surface and the next surface. Half-aperture indicates half the aperture size of the current surface. When the interval between the 24 surfaces is 10.182 mm, clear alignment is possible when the object plane is tilted at 62°, and the image plane tilt angle is 17.0845°.

[0108] Figure 14 This is the light fan diagram of the Schahm lens provided in Embodiment 2 of this utility model. The light fan diagram is one of the most commonly used evaluation methods in modern optical design. In this diagram, the horizontal axis represents the beam aperture, and the vertical axis represents the transverse aberration. The ideal curve is a straight line coinciding with the horizontal axis, indicating that all light rays converge at the same point on the image plane. The interval corresponding to the vertical axis of the curve is the maximum dispersion range of the beam on the ideal image plane. The light fan diagram can reflect not only monochromatic aberrations of different wavelengths but also the magnitude of transverse chromatic aberration. Figure 14 It can be seen that the SAM lens closely approximates the horizontal axis at all wavelengths in all fields of view, indicating that the transverse aberration of each wavelength of the SAM lens is well corrected. At the same time, there is no obvious dispersion of each wavelength, indicating that the chromatic aberration of the SAM lens is also well corrected, thus ensuring that the SAM lens can meet the requirements of high-resolution imaging.

[0109] Figure 15 This is a field curvature distortion curve of a Sham lens provided in Embodiment 2 of this utility model. In the coordinate system on the left side of the figure, the horizontal axis represents the magnitude of the field curvature, in mm; the vertical axis represents the normalized image height, which has no unit; where T represents the meridion and S represents the sagitta; Figure 15 It can be seen that the lens provided in this embodiment effectively controls field curvature, meaning that during imaging, the difference in image quality between the center and the periphery is small, resulting in good consistency. 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 15As can be seen, the distortion of the lens provided in this embodiment has been well corrected, with optical distortion less than ±0.66%.

[0110] Figure 16 The MTF curve of the positive imaging of the Sham lens provided in Embodiment 2 of this utility model is shown below. Figure 16 As shown, the lens provided in this embodiment has an image quality of 50pl / mm from the center field of view to the edge field of view that is higher than 0.78MTF when imaging in positive mode, and the imaging has excellent resolution.

[0111] Figure 17 The oblique imaging MTF curve of the Sham lens provided in Embodiment 2 of this utility model is shown below. Figure 17 As shown, the lens provided in this embodiment has an image quality of 50pl / mm from the center field of view to the edge field of view that is higher than 0.67MTF when imaging at an angle, and the imaging has excellent resolution.

[0112] Example 3

[0113] Continue to refer to Figures 7-9 The SAM lens provided in Embodiment 3 of this utility model includes a front flat glass CG1, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, an aperture STO, a sixth lens L6, a seventh lens L7, an eighth lens L8, a ninth lens L9, a tenth lens L10, and a rear flat glass CG2 arranged sequentially along the optical axis from the object plane to the image plane.

[0114] Table 3 details the surface type, radius of curvature, thickness, material (refractive index / Abbe number), and half-aperture of each lens in the Sham lens provided in Example 3, according to a feasible implementation method. The Sham lenses in Table 1 correspond to... Figures 7-9 The Sham lens shown.

[0115] Table 3 Design values ​​of optical physical parameters for Sham lenses

[0116]

[0117] The surface numbers in Table 3 are assigned according to the surface sequence of each lens; "1" represents the object-side surface of the first lens, "2" represents the image-side surface of the first lens, and so on; the radius of curvature represents the degree of curvature of the lens surface, with a positive value indicating that the surface bends towards the image plane and a negative value indicating that the surface bends towards the object plane; 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, with a blank space indicating that the current position is air and the refractive index is 1; the Abbe number represents the dispersion characteristics of the material between the current surface and the next surface. Half-aperture indicates half the aperture size of the current surface. When the interval between the 24 surfaces is 10.205 mm, clear alignment is possible when the object plane is tilted at 62°, and the image plane tilt angle is 16.9457°.

[0118] Figure 18 This is the light fan diagram of the Schahm lens provided in Embodiment 3 of this utility model. The light fan diagram is one of the most commonly used evaluation methods in modern optical design. In this diagram, the horizontal axis represents the beam aperture, and the vertical axis represents the transverse aberration. The ideal curve is a straight line coinciding with the horizontal axis, indicating that all light rays converge at the same point on the image plane. The interval corresponding to the vertical axis of the curve is the maximum dispersion range of the beam on the ideal image plane. The light fan diagram can reflect not only monochromatic aberrations of different wavelengths but also the magnitude of transverse chromatic aberration. Figure 18 It can be seen that the SAM lens closely approximates the horizontal axis at all wavelengths in all fields of view, indicating that the transverse aberration of each wavelength of the SAM lens is well corrected. At the same time, there is no obvious dispersion of each wavelength, indicating that the chromatic aberration of the SAM lens is also well corrected, thus ensuring that the SAM lens can meet the requirements of high-resolution imaging.

[0119] Figure 19 This is a field curvature distortion curve of a Sham lens provided in Embodiment 3 of this utility model. In the coordinate system on the left side of the figure, the horizontal axis represents the magnitude of the field curvature in mm; the vertical axis represents the normalized image height, which has no unit; where T represents the meridion and S represents the sagitta; Figure 19 It can be seen that the lens provided in this embodiment effectively controls field curvature, meaning that during imaging, the difference in image quality between the center and the periphery is small, resulting in good consistency. 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 19 As can be seen, the distortion of the lens provided in this embodiment has been well corrected, with optical distortion less than ±0.66%.

[0120] Figure 20 The MTF curve of the positive imaging of the Sham lens provided in Embodiment 3 of this utility model is shown below. Figure 20As shown, the lens provided in this embodiment has an image quality of 50pl / mm from the center field of view to the edge field of view that is higher than 0.78MTF when imaging in positive mode, and the imaging has excellent resolution.

[0121] Figure 21 The oblique imaging MTF curve of the Sham lens provided in Embodiment 3 of this utility model is shown below. Figure 21 As shown, the lens provided in this embodiment has an image quality of 50pl / mm from the center field of view to the edge field of view that is higher than 0.67MTF when imaging at an angle, and the imaging has excellent resolution.

[0122] To provide a clearer explanation of the above embodiments, Table 4 details the specific optical physical parameters of each lens in the Sham lens provided in embodiments one to three of this utility model.

[0123] Table 4 Design values ​​of optical physical parameters for Sham lenses

[0124] Example 1 Example 2 Example 3 θ 16.7576 17.0845 16.9457 TTL / IM 5.1467 5.1394 5.1413 TTL 59.1870 59.1030 59.1250 EFL 35.5836 35.9098 35.5517 ΦZ1 / ΦZ2 -0.4319 -0.4339 -0.6392 Nd2 / Nd1 1.1074 1.0969 1.1030 ΦL2 / ΦL1 -2.5364 -2.5437 -2.2451 Nd9 / Nd8 1.1097 1.1349 1.1371 Vd4 / Vd3 1.8441 1.7122 1.6973 MAX.DISG -0.6599％ -0.5174％ -0.5851％ MIN.|Ω6, Ω7| 6.9116 7.0801 6.4865 Φ1 -0.0215 -0.0235 -0.0264 Φ2 0.0547 0.0599 0.0594 Φ3 -0.0125 -0.0143 -0.0124 Φ4 0.0464 0.0491 0.0488 Φ5 -0.0603 -0.0620 -0.0619 Φ6 -0.0275 -0.0272 -0.0267 Φ7 0.0074 0.0086 0.0122 Φ8 -0.0342 -0.0351 -0.0239 Φ9 0.0479 0.0490 0.0370 Φ10 0.0229 0.0212 0.0197

[0125] The specific embodiments described above do not constitute a limitation on the scope of protection of this 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 modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the scope of protection of this utility model.

Claims

1. A Sham 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, a ninth lens, and a tenth lens arranged sequentially along the optical axis from the object plane to the image plane; The first lens has negative optical power, the second lens has positive optical power, the third lens has negative optical power, the fourth lens has positive optical power, the fifth lens has negative optical power, the sixth lens has negative optical power, the seventh lens has positive optical power, the eighth lens has negative optical power, the ninth lens has positive optical power, and the tenth lens has positive optical power. The first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens, the eighth lens, the ninth lens, and the tenth lens are all glass spherical lenses.

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

3. The Sham lens according to claim 1, characterized in that, The total optical power of the first lens, the second lens, the third lens, the fourth lens and the fifth lens is ΦZ1, and the total optical power of the sixth lens, the seventh lens and the eighth lens is ΦZ2, where -0.6400≤ΦZ1 / ΦZ2≤-0.4300.

4. The Sham lens according to claim 1, characterized in that, The optical power of the first lens is ΦL1, the optical power of the second lens is ΦL2, and -2.5500 < ΦL2 / ΦL1 < -2.2400.

5. The Sham lens according to claim 1, characterized in that, The refractive index of the first lens is Nd1, and the refractive index of the second lens is Nd2, with 1.0900≤Nd2 / Nd1≤1.1100.

6. The Sham lens according to claim 1, characterized in that, The refractive index of the ninth lens is Nd9, and the refractive index of the eighth lens is Nd8, with 1.1000≤Nd9 / Nd8≤1.1400.

7. The Sham lens according to claim 1, characterized in that, The shape factor of the sixth lens is Ω6, and the shape factor of the seventh lens is Ω7, where 6.48000 ≤ MIN.|Ω6, Ω7| ≤ 7.0900.

8. The Sham lens according to claim 1, characterized in that, The Abbe number of the third lens is Vd3, and the Abbe number of the fourth lens is Vd4, where 1.23000 ≤ Vd4 / Vd3.

9. The Sham lens according to claim 1, characterized in that, The SAM lens also includes a front plate glass and a rear plate glass, the front plate glass being located on the object side of the first lens and the rear plate glass being located on the image side of the tenth lens.

10. The Sham lens according to claim 9, characterized in that, The distance from the object side to the image plane of the front flat glass is TTL, and the half-image height of the SAM lens is IM, where 5.1300≤TTL / IM≤5.1500.

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