A samm lens based on near ultraviolet band point light source detection and electronic equipment

Abstract

This invention discloses a Sham lens and electronic device for near-ultraviolet point light source detection. The lens comprises twelve lenses arranged sequentially along an optical axis from the object side to the image side, all of which are spherical lenses. Specifically, the first lens has positive refractive index, with a planar object side and a convex image side; the second lens has positive refractive index, with a convex object side and a concave image side; the third lens has positive refractive index, with a convex object side and a concave image side; the fourth lens has positive refractive index, with a convex object side and a concave image side, and so on. This optical system, through a series of targeted designs including a global surface design, high relative illumination, optimized structural compactness and back focal space, precise matching of the Sham angle, fixed magnification, and compatibility with large-area sensors, achieves significant improvements in imaging performance, system stability, integration convenience, and operational efficiency, meeting the needs of modern high-precision machine vision applications.

Description

Technical Field

[0001] This invention relates to the field of SAM lens technology, and more particularly to a SAM lens and electronic device for near-ultraviolet band point light source detection. Background Technology

[0002] Scheimpflug lenses are built upon Scheimpflug's principle, achieving sharp imaging of tilted object planes by tilting the image plane, thus significantly extending the depth of field in specific applications. As modern machine vision technology advances towards higher precision and efficiency, more stringent requirements are placed on optical systems: on the one hand, larger apertures (i.e., smaller F# values) are needed to increase light throughput, improve signal-to-noise ratio, adapt to low-light conditions, or achieve millisecond-level exposure; on the other hand, larger image plane sizes are required to match high-resolution, large-area image sensors, thereby covering a wider field of view in a single image.

[0003] However, current SAM lenses on the market still have shortcomings in several key technical indicators: First, traditional designs are mostly designed for the visible or near-infrared bands, lacking specific optimization for the near-ultraviolet band; second, they mainly rely on aspherical optical elements, leading to increased processing and assembly difficulties; third, they usually use small apertures, resulting in insufficient light intake, making it difficult to work in low-light environments or requiring significantly longer exposure times, thus unsuitable for detecting high-speed moving objects; fourth, the relative illumination is generally low (often below 60%), resulting in obvious vignetting at the image edges, affecting the accuracy of quantitative image analysis; fifth, most products use a C-interface design, limiting the system's functional expandability; sixth, if the initial structure does not have image-side telecentric characteristics, the principal ray will enter the sensor at an angle, and when the object moves within the depth of field or undergoes height changes, the imaging magnification changes, leading to uncorrectable errors in image-based precision size measurements; seventh, existing lens systems cannot cover larger sensor target surfaces.

[0004] In conclusion, although SAM lenses exhibit significant advantages in depth-of-field extension due to their unique imaging mechanism, they still have a series of technical limitations in terms of light transmission capability, image plane coverage, spectral adaptability, optical performance, and system scalability. They are unable to fully meet the comprehensive needs of modern machine vision in terms of high-speed, high-precision, and large field-of-view imaging, and further optimization is urgently needed at the optical design and system integration levels. Summary of the Invention

[0005] In view of this, the object of the present invention is to provide a Sham lens and electronic device for detecting a point source in the near-ultraviolet band. This lens can at least solve one of the technical shortcomings mentioned in the background art. According to one aspect of the present invention, a Sham lens for detection based on a near-ultraviolet point light source is provided, wherein the lens comprises twelve lenses arranged sequentially along an optical axis from the object side to the image side, wherein... The first lens has positive refractive index, with a flat object-side surface and a convex image-side surface; The second lens has positive refractive index, with a convex object-side surface and a concave image-side surface; The third lens has positive refractive index, with a convex object-side surface and a concave image-side surface; The fourth lens has a positive refractive index, with a convex object-side surface and a concave image-side surface; The fifth lens has positive refractive index, and both the object-side and image-side surfaces are convex. The sixth lens has a negative refractive index, and both the object-side and image-side surfaces are concave. The seventh lens has a negative refractive index, with a convex object-side surface and a concave image-side surface; The eighth lens has a negative refractive index, and both the object-side and image-side surfaces are concave. The ninth lens has positive refractive index, and both the object-side and image-side surfaces are convex. The tenth lens has a negative refractive index, and both the object-side and image-side surfaces are concave. The eleventh lens has positive refractive index, with a concave object side and a convex image side; The twelfth lens has positive refractive index, and the object side is convex, while the image side is either convex or flat.

[0006] The aforementioned technical solution systematically addresses some of the technical limitations of traditional SAM lenses at the optical design level by employing the ratio and power distribution of twelve spherical lenses. The core of its design strategy lies in utilizing a combination of spherical lenses to achieve high-performance imaging while simultaneously ensuring fabrication feasibility and system stability.

[0007] In terms of specific optical configuration, firstly, it employs a system composed entirely of spherical lenses, avoiding the sensitivity to surface accuracy and high manufacturing costs associated with aspherical elements in the ultraviolet band, thus improving process feasibility. Secondly, the dense arrangement of multiple positive refractive index lenses in the front group provides a foundation for achieving a large aperture, helping to increase light throughput and meet the application requirements of low-light environments or short exposure times. Thirdly, the introduction of a telecentric optical path on the image side in the initial structure ensures that the principal ray enters the sensor target surface at a near-perpendicular angle at the image field. This characteristic effectively eliminates the magnification changes caused by the movement of objects within the depth of field, providing a prerequisite for image-based precision size measurement. Fourthly, the staggered arrangement of positive and negative lenses and the balanced distribution of optical power help to fully correct various aberrations (especially chromatic aberration and field curvature in the ultraviolet band), providing a theoretical guarantee for achieving high resolution, high edge relative illumination, and matching large-size sensors. Finally, the compact sequential structure of the twelve lenses has the potential to achieve precise matching of long back focal length and Sham angle within a limited physical space, thus reserving space for system integration and functional expansion.

[0008] In summary, this lens design is not a simple series of isolated lenses, but a collaborative design aimed at balancing ultraviolet band performance, manufacturing processes, and system integration requirements. By using a global initial structure with an image-side telecentric architecture, it specifically addresses the common shortcomings of traditional SAM lenses in terms of ultraviolet optimization, measurement accuracy, light transmission capability, image quality consistency, and mechanical compatibility, demonstrating promising engineering application prospects and technical integrity.

[0009] In some embodiments, the lens satisfies the following condition: 1.7<Nd1<1.9; 1.7<Nd2<1.8; 1.7<Nd3<1.8; 1.7<Nd4<1.8; 1.5<Nd5<1.6; 1.8<Nd6<1.9; 1.8<Nd7<1.9; 1.8<Nd8<1.9; 1.4 < Nd9 < 1.5; 1.8 < Nd 10 <1.9; 1.6 < Nd 11 <1.7; 1.9 < Nd 12 <2.0; In the formula, Nd1, Nd2, Nd3, Nd4, Nd5, Nd6, Nd7, Nd8, Nd9, Nd 10 、Nd 11 、Nd 12 These represent the refractive indices of the first to twelfth lenses, respectively.

[0010] The aforementioned technical solutions aim to optimize the overall system performance and balance various aberrations. These conditional equations collectively constitute the key material basis for achieving high-performance ultraviolet optical imaging.

[0011] Specifically, the refractive index settings of each lens exhibit a clear design logic: First, the first to fourth lenses and the sixth to eighth lenses all use high-refractive-index materials (Nd>1.7). Such materials are beneficial for improving the system's optical power contribution and effectively controlling field curvature and astigmatism, providing support for large-aperture designs, while also helping to reduce the overall system length and achieve a compact structure. Second, the fifth, ninth, and eleventh lenses use medium-to-low refractive-index materials (Nd between 1.4 and 1.7). These materials typically possess superior dispersion characteristics, and their introduction complements the high-refractive-index lenses, effectively correcting for axial and magnification chromatic aberration that may exist in the ultraviolet band. Particularly noteworthy is that the twelfth lens has the highest refractive index setting in the entire system (1.9 < Nd). 12 <2.0), this move aims to further improve the flatness of the image plane at the edge of the field of view and enhance the system's ability to control the initial structure as the image-side telecentric characteristics, thereby matching the imaging requirements of large target area sensors.

[0012] In summary, this series of refractive index conditional formulas achieves a systematic balance between controlling spherical aberration, field curvature, astigmatism, and ultraviolet chromatic aberration through the alternating and combined use of high, medium, and low refractive index materials. This not only ensures the technological feasibility of the global surface design route but also lays the physical foundation for achieving high resolution and high image surface illumination uniformity.

[0013] In some embodiments, the lens satisfies the following condition: 45<Vd1<50; 45<Vd2<50; 50<Vd3<55; 50<Vd4<55; 65<Vd5<70; 35<Vd6<40; 25<Vd7<30; 35<Vd8<40; 70<Vd9<75; 35<Vd 10 <40; 55 <Vd 11 <60; 35 < Vd 12 <40 In the formula, Vd1, Vd2, Vd3, Vd4, Vd5, Vd6, Vd7, Vd8, Vd9, Vd 10 Vd 11 Vd 12 These represent the Abbe numbers of the first to twelfth lenses, respectively.

[0014] In the above technical solutions, these conditional expressions work synergistically with the aforementioned refractive index parameters to jointly construct the optical material basis for achieving high-fidelity ultraviolet imaging.

[0015] Specifically, firstly, the first to fourth lenses in the front group of the optical path are given high Abbe numbers (Vd>45). This low dispersion characteristic helps to effectively suppress axial chromatic aberration in the early stages of light convergence, laying a good foundation for chromatic aberration control of the system. Secondly, the fifth and ninth lenses use the highest Abbe numbers in the entire system (65<Vd5<70, 70<Vd9<75). These two ultra-low dispersion lenses constitute key chromatic aberration correction nodes in the optical path. In conjunction with high dispersion lenses, they can perform in-depth correction of complex chromatic aberrations such as residual secondary spectra. Crucially, the sixth, seventh, eighth, tenth, and twelfth lenses are all given low Abbe numbers (Vd < 40), especially the seventh lens, whose Abbe number is limited to the range of 25 to 30. The introduction of these high-dispersion elements, through the alternating arrangement of "high-low-high" with the aforementioned low-dispersion lenses, constructs a complex chromatic aberration compensation structure, thereby achieving a high-precision balance between positive and negative dispersion globally, so as to achieve synchronous correction of axial and magnification chromatic aberration in the ultraviolet band.

[0016] In summary, this series of Abbe number conditions and refractive index parameters together constitute a highly synergistic material selection system. By combining low-dispersion and high-dispersion lenses in a specific order and proportion, this design achieves deep control over ultraviolet wave aberrations. The aforementioned dispersion management strategy is the core of how the global surface lens combination achieves high resolution and excellent chromatic aberration correction performance in this near-ultraviolet SHANGHAI lens, even after sacrificing the additional degrees of freedom of aspherical lenses.

[0017] In some embodiments, the fifth lens and the sixth lens are cemented together to form a first cemented lens group.

[0018] Compared to simple single-lens combinations or designs containing aspherical surfaces, this glued assembly offers several unique combined advantages.

[0019] Specifically, its unique advantages are mainly reflected in the following three aspects: First, the cemented assembly, through the tight bonding of the positive and negative lenses, constitutes an intrinsic chromatic aberration correction unit at the physical level. It can efficiently correct the axial chromatic aberration of the system in the ultraviolet band without relying on the complex surface shape of the aspherical lens, utilizing the optical power and material dispersion characteristics of the spherical lens itself, thus improving the lens resolution and imaging contrast. Second, the cemented structure merges two independent air-glass interfaces into one. This design significantly reduces Fresnel reflection loss of ultraviolet light on the lens surface, thereby effectively improving the transmittance of the entire system; this is crucial for ultraviolet imaging with limited light energy, helping to improve the signal-to-noise ratio and reducing the difficulty of subsequent coating processes. Finally, from a mechanical structure and assembly perspective, the cemented assembly solidifies two optical elements into a more rigid whole. This greatly reduces the assembly complexity and uncertainty of centering and spacing control of the two lenses separately, which not only improves production yield, but more importantly, enhances the long-term stability of the entire lens under complex working conditions, and avoids slight changes in the relative position between the lenses due to vibration or temperature changes, thereby ensuring image quality.

[0020] In summary, the cemented design of the fifth and sixth lenses is an optimization measure that combines optical and mechanical benefits in order to achieve excellent ultraviolet imaging performance.

[0021] In some embodiments, the lens satisfies the following condition: Nd6- Nd5>0.2; Vd5- Vd6>30 In the formula, Nd5 and Nd6 represent the refractive indices of the fifth and sixth lenses, respectively; Vd5 and Vd6 represent the Abbe numbers of the fifth and sixth lenses, respectively.

[0022] In the above technical solution, the two inequalities together form the basis for the glued assembly to achieve efficient aberration correction and system performance optimization.

[0023] Specifically, firstly, by making the refractive index of the negative lens significantly higher than that of the positive lens, the cemented lens assembly can effectively control its overall positive optical power while contributing the necessary negative optical power to correct system chromatic aberration. This avoids an excessively large positive contribution to Petzval and is beneficial for achieving flat-field targets and adapting to large target surfaces. Secondly, the Abbe number difference condition enables the cemented lens assembly to have dispersion compensation capabilities, accurately canceling the axial chromatic aberration accumulated by other positive optical power lens assemblies in the system, thus meeting the high image quality requirements of ultraviolet imaging.

[0024] In summary, the combined condition ensures that the fifth and sixth cemented groups achieve chromatic aberration correction while also taking into account field curvature control and structural compactness. This allows the near-ultraviolet SAM lens to still meet the requirements of key indicators such as high resolution and high image plane illumination uniformity even after giving up the freedom of aspherical design.

[0025] In some embodiments, the eighth lens and the ninth lens are cemented together to form a second cemented lens group.

[0026] In the above technical solution, the eighth lens and the ninth lens are cemented together to form a second cemented lens group. This configuration is one of the key designs for achieving high-order aberration balance and improving edge field of view performance in this global surface optical system. This combination continues the system's strategy of using cemented components to correct aberrations and has been specifically optimized for specific aberrations.

[0027] Specifically, firstly, this component employs a combination of negative and positive refractive indices, echoing the positive and negative cementation of the previous component, together constructing a distributed aberration correction system. This layout facilitates fine compensation for residual chromatic aberration at different field-of-view positions, ensuring that the imaging focus at different positions tends to be consistent in the ultraviolet band. Secondly, the location of this cemented assembly corresponds to the regions where major aberrations (such as coma and astigmatism) occur. Its combination can effectively correct these off-axis aberrations, thereby significantly improving the imaging quality and relative illumination of the edge fields of view, which helps to match large-area sensors and achieve high uniformity imaging across the entire image plane. Finally, from a structural perspective, the formation of this cemented assembly reduces two air-glass interfaces, which not only improves the overall transmittance of the system in the ultraviolet band and reduces the risk of ghosting and stray light, but also further simplifies the assembly process and enhances the structural stability and environmental adaptability of the optical system.

[0028] In summary, the second cemented lens group, consisting of the eighth and ninth lenses, represents a further refinement of the lens design in terms of global aberration balance and edge performance optimization. Through its synergy with the first cemented lens group, it ensures that the system, while adhering to the global image plane technology approach, can still achieve high resolution and high image plane illumination uniformity across the entire image field.

[0029] In some embodiments, the lens satisfies the following condition: Nd8- Nd9>0.3; Vd9- Vd8>30 In the formula, Nd8 and Nd9 represent the refractive indices of the fifth and sixth lenses, respectively; Vd8 and Vd9 represent the Abbe numbers of the fifth and sixth lenses, respectively.

[0030] In the above technical solution, two conditional formulas ensure that the adhesive assembly can effectively fulfill its design function from the perspective of the optical properties of the material.

[0031] Specifically, firstly, the refractive index difference condition requires the eighth lens, with its negative optical power, to have a significantly higher refractive index than the ninth lens, with its positive optical power. This characteristic allows the cemented assembly to maintain low or even negative Petzval and contribution values ​​while providing the necessary local optical power to correct astigmatism, field curvature, and other off-axis aberrations. This strongly supports the flatness of the entire image plane, which is beneficial for matching large-size sensors and improving edge relative illumination. Secondly, the Abbe number difference condition makes this component a highly efficient local chromatic aberration corrector, capable of accurately compensating for residual magnification chromatic aberration in the system. This ensures consistent imaging magnification at different ultraviolet wavelengths at different field-of-view positions, thereby guaranteeing the resolution and color fidelity of the entire image plane, especially the edge regions.

[0032] In summary, this combination of conditional expressions defines the material pairing relationships that the second cemented group must satisfy to achieve its specific optical functions of correcting off-axis aberrations and chromatic aberration. Their synergistic effect with the conditional expressions of the first cemented group constitutes the technical basis for this global surface near-ultraviolet SCAM lens to achieve uniform, high-quality imaging from center to edge.

[0033] In some embodiments, all twelve lenses are made of glass.

[0034] In the above technical solution, all twelve lenses in the lens are made of glass, which avoids the inherent limitations of polymer materials in optical systems.

[0035] Specifically, firstly, glass materials, especially fused silica and certain optical glasses, possess inherently high transmittance and excellent radiation stability in the ultraviolet band. This ensures efficient transmission of ultraviolet light signals and prevents material yellowing or performance degradation caused by prolonged irradiation, something polymer materials cannot match. Secondly, glass materials offer a wider and more precise range of refractive indices (Nd) and Abbe numbers (Vd). This allows optical designers to freely select the most suitable ideal optical material for each lens under the aforementioned stringent constraints, thereby achieving correction of chromatic aberration and monochromatic aberration under global surface design. Finally, the coefficient of thermal expansion of glass is much lower than that of plastics, and its temperature coefficient of refractive index (dn / dT) is generally more stable. This ensures that the lens maintains stable image quality and focal plane position when the ambient temperature changes, meeting the high thermal stability requirements of industrial applications. Simultaneously, the high hardness and wear resistance of glass ensure the durability of the optical surface during cleaning and long-term use.

[0036] In summary, the all-glass construction helps this UV SAM lens achieve comprehensive goals in terms of UV transmittance, aberration correction accuracy, environmental stability, and long-term reliability.

[0037] According to another aspect of the present invention, an electronic device is provided, comprising a Sham lens for detection based on a near-ultraviolet band point light source as described above; and An image sensor is configured to receive the image formed by the Sham lens used for detection based on a near-ultraviolet band point light source.

[0038] In the above technical solution, the advantage of the electronic device relies on the Sham lens for detection based on a near-ultraviolet band point light source, which will not be elaborated here. Attached Figure Description

[0039] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0040] Figure 1 This is a schematic diagram of an example 1 of a Sham lens for detection based on a near-ultraviolet band point light source according to the present invention; wherein, the upper figure is a schematic diagram of the system in a coaxial state, and the lower figure is a schematic diagram of the system in a Sham state.

[0041] Figure 2 This is an example 1 of the MTF curve of a Sham lens for detection based on a near-ultraviolet band point light source according to the present invention; wherein, the left figure is the MTF curve of the system in the coaxial state, and the right figure is the MTF curve of the system in the Sham state.

[0042] Figure 3 This is a defocus MTF curve of an example 1 of a SAM lens for near-ultraviolet band point light source detection according to the present invention; wherein, the left figure is the defocus MTF curve of the system in the coaxial state, and the right figure is the defocus MTF curve of the system in the SAM state.

[0043] Figure 4 This is a relative illumination diagram of an example 1 of a Sham lens for detection based on a near-ultraviolet band point light source according to the present invention; wherein, the left diagram is the relative illumination diagram of the system in a coaxial state, and the right diagram is the relative illumination diagram of the system in a Sham state.

[0044] Figure 5 This is a distortion curve diagram of an example 1 of a Sham lens for detection based on a near-ultraviolet band point light source according to the present invention; wherein, the left figure is the distortion curve diagram of the system in a coaxial state, and the right figure is the distortion curve diagram of the system in a Sham state.

[0045] Figure 6This is an axial aberration diagram of an example 1 of a Sham lens for detection based on a near-ultraviolet band point light source according to the present invention; wherein, the left diagram is the axial aberration diagram of the system in a coaxial state, and the right diagram is the axial aberration diagram of the system in a Sham state.

[0046] Figure 7 This is the optical fan pattern of a system in a coaxial state for a Sham lens used for detection based on a near-ultraviolet band point light source according to Example 1 of the present invention.

[0047] Figure 8 This is a fan-shaped image of the system in the Sham state of an example 1 of the present invention, which is based on a near-ultraviolet band point light source detection Sham lens. Figure 9 This is a schematic diagram of an example 2 of a Sham lens for detection based on a near-ultraviolet band point light source according to the present invention; wherein, the upper figure is a schematic diagram of the system in a coaxial state, and the lower figure is a schematic diagram of the system in a Sham state.

[0048] Figure 10 This is an example 2 of the MTF curve of a Sham lens for detection based on a near-ultraviolet band point light source according to the present invention; wherein, the left figure is the MTF curve of the system in the coaxial state, and the right figure is the MTF curve of the system in the Sham state.

[0049] Figure 11 This is a defocus MTF curve of an example 2 of a SAM lens for near-ultraviolet band point light source detection according to the present invention; wherein, the left figure is the defocus MTF curve of the system in the coaxial state, and the right figure is the defocus MTF curve of the system in the SAM state.

[0050] Figure 12 This is a relative illumination diagram of an example 2 of a Sham lens for detection based on a near-ultraviolet band point light source according to the present invention; wherein, the left diagram is the relative illumination diagram of the system in a coaxial state, and the right diagram is the relative illumination diagram of the system in a Sham state.

[0051] Figure 13 This is a distortion curve diagram of an example 2 of a Sham lens for detection based on a near-ultraviolet band point light source according to the present invention; wherein, the left figure is the distortion curve diagram of the system in a coaxial state, and the right figure is the distortion curve diagram of the system in a Sham state.

[0052] Figure 14 This is an axial aberration diagram of an example 2 of a Sham lens for detection based on a near-ultraviolet band point light source according to the present invention; wherein, the left diagram is the axial aberration diagram of the system in a coaxial state, and the right diagram is the axial aberration diagram of the system in a Sham state.

[0053] Figure 15 This is the optical fan pattern of a system in a coaxial state for a Sham lens example 2 based on a near-ultraviolet band point light source detection according to the present invention.

[0054] Figure 16 This is a fan-shaped optical pattern of a system in a Sham state according to Example 2 of the present invention, which is based on a near-ultraviolet band point light source detection Sham lens. Figure 17 This is a schematic diagram of an example 3 of a Sham lens for detection based on a near-ultraviolet band point light source according to the present invention; wherein, the upper figure is a schematic diagram of the system in a coaxial state, and the lower figure is a schematic diagram of the system in a Sham state.

[0055] Figure 18 This is an example 3 of the MTF curve of a Sham lens for detection based on a near-ultraviolet band point light source according to the present invention; wherein, the left figure is the MTF curve of the system in the coaxial state, and the right figure is the MTF curve of the system in the Sham state.

[0056] Figure 19 This is a defocus MTF curve of an example 3 of a SAM lens for near-ultraviolet band point light source detection according to the present invention; wherein, the left figure is the defocus MTF curve of the system in the coaxial state, and the right figure is the defocus MTF curve of the system in the SAM state.

[0057] Figure 20 This is a relative illumination diagram of an example 3 of a Sham lens for detection based on a near-ultraviolet band point light source according to the present invention; wherein, the left diagram is the relative illumination diagram of the system in a coaxial state, and the right diagram is the relative illumination diagram of the system in a Sham state.

[0058] Figure 21 This is a distortion curve diagram of an example 3 of a Sham lens for detection based on a near-ultraviolet band point light source according to the present invention; wherein, the left figure is the distortion curve diagram of the system in a coaxial state, and the right figure is the distortion curve diagram of the system in a Sham state.

[0059] Figure 22 This is an axial aberration diagram of an example 3 of a Sham lens for detection based on a near-ultraviolet band point light source according to the present invention; wherein, the left diagram is the axial aberration diagram of the system in a coaxial state, and the right diagram is the axial aberration diagram of the system in a Sham state.

[0060] Figure 23 This is the optical fan pattern of a system in a coaxial state for a Sham lens used for detection based on a near-ultraviolet band point light source according to Example 3 of the present invention.

[0061] Figure 24 This is a fan-shaped image of the system in the Sham state of an example 3 of the present invention, which is based on a Sham lens for detection of a near-ultraviolet point source. Figure 25 This is a schematic diagram of the structure of Example 4 of the electronic device of the present invention. Detailed Implementation

[0062] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be particularly noted that the following embodiments are for illustrative purposes only and do not limit the scope of the invention. Similarly, the following embodiments are only some, not all, embodiments of the present invention, and all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0063] The purpose of this invention is to provide a Sham lens and electronic device for detection based on a near-ultraviolet point light source, exhibiting high optical performance. Embodiments according to the invention will now be described in detail with reference to the accompanying drawings.

[0064] Figure 1 , Figure 9 , Figure 17 These are cross-sectional views of a SAM lens (optical system) for near-ultraviolet point source detection according to Examples 1 to 3. The SAM lenses for near-ultraviolet point source detection according to each example are used in imaging devices including digital cameras, digital still cameras, broadcast cameras, surveillance cameras, etc., and in electronic devices with interchangeable lenses. In each cross-sectional view, the left side is the object-side OBJ and the right side is the image-side IMA. In each cross-sectional view, Li represents the i-th lens, ST represents the aperture stop (fixed aperture stop or visible aperture stop). IMA represents the image plane, and when the SAM lenses for near-ultraviolet point source detection according to each example are used in the imaging optical system of a digital camera or digital still camera, a solid-state imaging element (photoelectric conversion element), such as a CMOS image sensor or a CCD image sensor, is arranged on the image plane IMA.

[0065] According to the various examples of Sham lenses for near-ultraviolet point source detection, the lenses, from the object side to the image side along an optical axis, are sequentially arranged as the first to fourth lenses; all twelve lenses are made of glass. The lens consists of twelve lenses arranged sequentially along an optical axis from the object side to the image side, and all twelve lenses are spherical lenses; wherein... The first lens L1 has positive refractive index, with a flat object-side surface and a convex image-side surface; The second lens L2 has a positive refractive index, with a convex object-side surface and a concave image-side surface; The third lens L3 has a positive refractive index, with a convex object-side surface and a concave image-side surface; The fourth lens L4 has a positive refractive index, with a convex object-side surface and a concave image-side surface; The fifth lens L5 has a positive refractive index, and both the object-side and image-side surfaces are convex. The sixth lens L6 has a negative refractive index, and both the object-side and image-side surfaces are concave. The seventh lens L7 has a negative refractive index, with a convex object-side surface and a concave image-side surface; The eighth lens L8 has a negative refractive index, and both the object-side and image-side surfaces are concave. The ninth lens L9 has a positive refractive index, and both the object-side and image-side surfaces are convex. The tenth lens L10 has a negative refractive index, and both the object-side and image-side surfaces are concave. The eleventh lens L11 has positive refractive index, with a concave object side and a convex image side; The twelfth lens L12 has a positive refractive index, with a convex object side and a convex or flat image side.

[0066] The fifth lens L5 and the sixth lens L6 are cemented together to form the first cemented lens group.

[0067] The eighth lens L8 and the ninth lens L9 are cemented together to form a second cemented lens group.

[0068] The following setup conditions can be met based on the Schahm lens used for near-ultraviolet band point light source detection in each example: 1)1.7<Nd1<1.9; 1.7<Nd2<1.8; 1.7<Nd3<1.8; 1.7<Nd4<1.8; 1.5<Nd5< 1.6; 1.8<Nd6<1.9; 1.8<Nd7<1.9; 1.8<Nd8<1.9; 1.4<Nd9<1.5; 1.8<Nd 10 <1.9; 1.6 < Nd 11 <1.7; 1.9 < Nd 12 <2.0; 2)45<Vd1<50; 45<Vd2<50; 50<Vd3<55; 50<Vd4<55; 65<Vd5 <70; 35<Vd6<40; 25<Vd7<30; 35<Vd8<40; 70<Vd9<75; 35<Vd 10 <40; 55 <Vd 11 <60; 35 < Vd 12 <40; 3)Nd6- Nd5>0.2; Vd5- Vd6>30; 4)Nd8- Nd9>0.3; Vd9- Vd8>30; In the above conditional expressions, Nd1, Nd2, Nd3, Nd4, Nd5, Nd6, Nd7, Nd8, Nd9, and Nd... 10 、Nd 11 、Nd 12 Vd1, Vd2, Vd3, Vd4, Vd5, Vd6, Vd7, Vd8, Vd9, Vd... represent the refractive indices of the first to twelfth lenses, respectively. 10 Vd11 Vd 12 These represent the Abbe numbers of the first to twelfth lenses, respectively.

[0069] A detailed description of a Sham lens for near-ultraviolet band point light source detection, based on various examples, will now be provided.

[0070] Please refer to the optical structure of Example 1. Figure 1 The specific parameters of Example 1 are shown in Table 1 below. In Example 1, the lens focal length f' = 71.4 mm and the aperture number F# = 1.1. The system is in Sham mode, the angle between the object plane and the optical axis α = 51.7°, the angle between the image plane and the optical axis β = 38°, and the system's long back focal distance is 70.4 mm.

[0071] Table 1 Parameter Table for Example 1

[0072] Figure 2 The figures show the MTF curves for Example 1; the left figure shows the MTF curve of the system in coaxial mode, and the right figure shows the MTF curve of the system in SAM mode. In coaxial mode, the MTF curves for each field of view are compactly distributed. At a spatial frequency of 60 lp / mm, the central field of view MTF ≥ 0.7, and the peripheral field of view MTF ≥ 0.6. The meridional and sagittal curves are closely aligned, indicating excellent astigmatism control and overall performance close to the diffraction limit. In tilted (SAM) mode, although the high-frequency MTF of the system decreases slightly, at a spatial frequency of 60 lp / mm, the central field of view MTF is still ≥ 0.5, and the peripheral field of view MTF is ≥ 0.29, which meets the resolution requirements for tilted imaging, demonstrating good adaptability and imaging stability. Figure 3 The figures show the defocus MTF curves for Example 1; the left figure shows the defocus MTF curve when the system is in a coaxial configuration, and the right figure shows the defocus MTF curve when the system is in a SAM configuration. In the coaxial configuration, the peak values ​​of the defocus MTF curves for each field of view are concentrated, and the optimal focal plane position is consistent. At 60 lp / mm, the peak MTF of the center field of view is ≥0.65, and the peak MTF of the edge field of view is ≥0.55, demonstrating excellent depth-of-focus uniformity and defocus stability. In the tilted (SAM) configuration, although the optimal focal plane of each field of view shifts slightly and the MTF of the edge field of view decreases, the peak MTF of the center field of view at 60 lp / mm is still ≥0.55, which meets the defocus imaging requirements under tilted imaging, and the system exhibits good imaging stability. Figure 4 This is the relative illuminance diagram for Example 1; the left diagram shows the relative illuminance when the system is in a coaxial state, and the right diagram shows the relative illuminance when the system is in a Sham state. In the coaxial state, the relative illuminance decreases gradually with the increase of the field of view, and is still ≥80% at the maximum field of view, with excellent uniformity across the entire field of view; in the tilted (Sham) state, the relative illuminance distribution is even more gradual, with no significant drop in illuminance at the edge of the field of view, and good consistency across the entire field of view. Figure 5 The diagram shows the distortion curves for Example 1; the left diagram shows the distortion curve when the system is in a coaxial state, and the right diagram shows the distortion curve when the system is in a Sham state. In the coaxial state, the field curvature of the optical system of this invention is controlled within ±0.1 mm, and the maximum field distortion is ≤0.2%; in the tilted (Sham) state, the field curvature remains within ±0.1 mm, and the maximum field distortion is ≤0.3%. Both field curvature and distortion are at extremely low levels under both conditions, demonstrating excellent geometric aberration stability and adaptability to different operating conditions. Figure 6 The diagrams shown are axial aberration diagrams for Example 1; the left diagram shows the axial aberration diagram of the system in a coaxial state, and the right diagram shows the axial aberration diagram of the system in a Sham state. In the coaxial state, the optical system of this invention controls the axial aberration within ±0.06mm, with minimal focus shift at each wavelength; in the tilted (Sham) state, the axial aberration further converges to ±0.02mm, with high overlap of wavelength curves. Structural tilt does not introduce additional axial aberration, and the system exhibits excellent axial aberration stability and adaptability to various operating conditions. Figure 7 This is the optical fan plot of the system in Example 1 in a coaxial state. In the coaxial state, the lateral optical fan plot shows that the light rays of each field of view and each wavelength are closely converged, the maximum lateral aberration is ≤±50μm, and spherical aberration, coma, astigmatism and chromatic aberration are effectively controlled, with uniform aberration distribution across the entire field of view. Figure 8 The image shown is the optical fan plot of the system in the Sham state in Example 1. When the optical system is in the Sham (tilted) state, the lateral optical fan plot shows that the light rays of each field of view and each wavelength maintain good convergence, the maximum lateral aberration is ≤±100μm, and the spherical aberration, coma, astigmatism and chromatic aberration are effectively controlled. The structural tilt does not significantly deteriorate the aberration performance, and the system has excellent tilt and imaging stability.

[0073] Please refer to the optical structure of Example 2. Figure 9 The specific parameters for Example 2 are shown in Table 2 below. In Example 2, the lens focal length f' = 71.4 mm and the aperture number F# = 1.1. The system is in Sham mode, the angle between the object plane and the optical axis α = 51.7°, the angle between the image plane and the optical axis β = 38°, and the system's long back focal distance is 70.4 mm.

[0074] Table 2 Example 2 Parameter Table

[0075] Figure 10The figures show the MTF curves for Example 2; the left figure shows the MTF curve of the system in coaxial mode, and the right figure shows the MTF curve of the system in SAM mode. In coaxial mode, the MTF curves for each field of view are compactly distributed. At a spatial frequency of 60 lp / mm, the central field of view MTF ≥ 0.7, and the peripheral field of view MTF ≥ 0.6. The meridional and sagittal curves are closely aligned, indicating excellent astigmatism control and overall performance close to the diffraction limit. In tilted (SAM) mode, although the high-frequency MTF of the system decreases slightly, at a spatial frequency of 60 lp / mm, the central field of view MTF is still ≥ 0.5, and the peripheral field of view MTF is ≥ 0.29, which meets the resolution requirements for tilted imaging conditions, demonstrating good adaptability and imaging stability. Figure 11 This is the defocus MTF curve for Example 2; the left graph shows the defocus MTF curve when the system is in a coaxial state, and the right graph shows the defocus MTF curve when the system is in a SAM state. In the coaxial state, the peak values ​​of the defocus MTF curves for each field of view are concentrated, and the optimal focal plane position is consistent. At 60 lp / mm, the peak MTF of the center field of view is ≥0.65, and the peak MTF of the edge field of view is ≥0.55, showing excellent uniformity of depth of focus and defocus stability. In the tilted (SAM) state, although the optimal focal plane of each field of view is slightly shifted and the MTF of the edge field of view is attenuated, the peak MTF of the center field of view at 60 lp / mm is still ≥0.55, which can meet the defocus imaging requirements under tilted imaging, and the system has good imaging stability. Figure 12 This is the relative illuminance diagram for Example 2; the left diagram shows the relative illuminance when the system is in a coaxial state, and the right diagram shows the relative illuminance when the system is in a Sham state. In the coaxial state, the relative illuminance decreases gradually with the increase of the field of view, and remains ≥80% at the maximum field of view, showing excellent uniformity across the entire field of view; in the tilted (Sham) state, the relative illuminance distribution is even more gradual, with no significant drop in illuminance at the edge of the field of view, resulting in better consistency across the entire field of view. Figure 13 The diagram shows the distortion curves for Example 2; the left diagram shows the distortion curve when the system is in a coaxial state, and the right diagram shows the distortion curve when the system is in a Sham state. In the coaxial state, the field curvature of the optical system of this invention is controlled within ±0.1 mm, and the maximum field distortion is ≤0.2%; in the tilted (Sham) state, the field curvature remains within ±0.1 mm, and the maximum field distortion is ≤0.3%. Both field curvature and distortion are at extremely low levels under both conditions, demonstrating excellent geometric aberration stability and adaptability to different operating conditions. Figure 14 This is an example of axial aberration diagrams; the left diagram shows the axial aberration diagram of the system in a coaxial state, and the right diagram shows the axial aberration diagram of the system in a Sham state. In the coaxial state, the optical system of this invention controls the axial aberration within ±0.06mm, with minimal focus shift at each wavelength; in the tilted (Sham) state, the axial aberration further converges to ±0.02mm, with high overlap of wavelength curves. The structural tilt does not introduce additional axial aberration, and the system exhibits excellent axial aberration stability. Figure 15This is an example 2 of the system of the present invention based on a Sham lens for detection of a near-ultraviolet point source, in a coaxial state. In the coaxial state, the lateral fan pattern shows that the light rays of each field of view and each wavelength are closely converged, the maximum lateral aberration is ≤±50μm, and spherical aberration, coma, astigmatism and chromatic aberration are effectively controlled, with uniform aberration distribution across the entire field of view. Figure 16 The image shown is the optical fan plot of the system in the Sham state in Example 2. When the optical system is in the Sham (tilted) state, the lateral optical fan plot shows that the light rays of each field of view and each wavelength maintain good convergence, the maximum lateral aberration is ≤±100μm, and the spherical aberration, coma, astigmatism and chromatic aberration are effectively controlled. The structural tilt does not significantly deteriorate the aberration performance, and the system has excellent tilt and imaging stability.

[0076] Please refer to the optical structure of Example 3. Figure 17 The specific parameters for Example 3 are shown in Table 3 below. In Example 3, the lens focal length f' = 71.39 mm and the aperture number F# = 1.1. The system is in Sham mode, the angle between the object plane and the optical axis α = 51.7°, the angle between the image plane and the optical axis β = 38°, and the system's long back focal distance is 70.4 mm.

[0077] Table 3 Example 3 Parameter Table

[0078] Figure 18 The figures show the MTF curves for Example 3; the left figure shows the MTF curve of the system in coaxial mode, and the right figure shows the MTF curve of the system in SAM mode. In coaxial mode, the MTF curves for each field of view are compactly distributed. At a spatial frequency of 60 lp / mm, the central field of view MTF ≥ 0.7, and the peripheral field of view MTF ≥ 0.6. The meridional and sagittal curves are closely aligned, indicating excellent astigmatism control and overall performance close to the diffraction limit. In tilted (SAM) mode, although the high-frequency MTF of the system decreases slightly, at a spatial frequency of 60 lp / mm, the central field of view MTF is still ≥ 0.5, and the peripheral field of view MTF is ≥ 0.29, which meets the resolution requirements for tilted imaging conditions, demonstrating good adaptability and imaging stability. Figure 19 This is the defocus MTF curve for Example 3; the left graph shows the defocus MTF curve when the system is in coaxial mode, and the right graph shows the defocus MTF curve when the system is in SAM mode. In coaxial mode, the peak values ​​of the defocus MTF curves for each field of view are concentrated, and the optimal focal plane position is consistent. At 60 lp / mm, the peak MTF of the center field of view is ≥0.65, and the peak MTF of the edge field of view is ≥0.55, showing excellent uniformity of depth of focus and defocus stability. In tilted (SAM) mode, although the optimal focal plane of each field of view is slightly shifted and the MTF of the edge field of view is attenuated, the peak MTF of the center field of view at 60 lp / mm is still ≥0.55, which can meet the defocus imaging requirements under tilted imaging, and the system has good imaging stability. Figure 20This is the relative illumination map for Example 3; the left image shows the relative illumination map when the system is in a coaxial state, and the right image shows the relative illumination map when the system is in a Sham state. In the coaxial state, the relative illumination decreases gradually with the increase of the field of view, and is still ≥80% at the maximum field of view, with excellent uniformity across the entire field of view; in the tilted (Sham) state, the relative illumination distribution is more gradual, with no significant drop in illuminance at the edge of the field of view, and better consistency across the entire field of view. Figure 21 The diagram shows the distortion curves for Example 3; the left diagram shows the distortion curve when the system is in a coaxial state, and the right diagram shows the distortion curve when the system is in a Sham state. In the coaxial state, the field curvature of the optical system of this invention is controlled within ±0.1 mm, and the maximum field distortion is ≤0.2%; in the tilted (Sham) state, the field curvature remains within ±0.1 mm, and the maximum field distortion is ≤0.3%. Both field curvature and distortion are at extremely low levels under both conditions, demonstrating excellent geometric aberration stability and adaptability to different operating conditions. Figure 22 This is an example of axial aberration diagrams; the left diagram shows the axial aberration diagram of the system in a coaxial state, and the right diagram shows the axial aberration diagram of the system in a Sham state. In the coaxial state, the optical system of this invention controls the axial aberration within ±0.06mm, with minimal focus shift at each wavelength; in the tilted (Sham) state, the axial aberration further converges to ±0.02mm, with high overlap of wavelength curves. Structural tilt does not introduce additional axial aberration, and the system exhibits excellent axial aberration stability. Figure 23 This is the optical fan plot of the system in Example 3 in a coaxial state. In the coaxial state, the lateral optical fan plot shows that the light rays of each field of view and each wavelength are closely converged, the maximum lateral aberration is ≤±50μm, and spherical aberration, coma, astigmatism and chromatic aberration are effectively controlled, with uniform aberration distribution across the entire field of view. Figure 24 The image shown is the lateral fan plot of the system in Example 3 in the Sham state. In the Sham (tilted) state, the optical system shows that the light rays in each field of view and each wavelength maintain good convergence, the maximum lateral aberration is ≤ ±100μm, and spherical aberration, coma, astigmatism and chromatic aberration are effectively controlled. The structural tilt does not significantly deteriorate the aberration performance, and the system has excellent tilt and imaging stability.

[0079] Based on Examples 1 to 3, this case has the following advantages: This optical system demonstrates significant advantages in performance, integration, and stability through a series of innovative optical and structural designs. Specifically, its core technical features are reflected in the following aspects: First, the system employs a global lens array (12 elements in total), which effectively reduces the difficulty of processing and assembly compared to designs that include aspherical elements, and avoids the surface accuracy sensitivity issues that aspherical elements may have in the ultraviolet band. Second, the system possesses high resolution and excellent imaging quality, meeting the requirement of clearly distinguishing ground details from high altitudes; at a spatial frequency of 60 lp / mm, the modulation transfer function (MTF) value is as high as 0.66 or higher in the center field of view, and better than 0.5 in the edge field of view, ensuring that the image is clear and sharp from the center to the edge. Third, the system features an initial structure with image-side telecentric characteristics, ensuring that the main ray is perpendicularly incident on the sensor image plane, eliminating the incident angle dependence of CCD / CMOS, and combined with a relative illumination of up to 81%, effectively improving the edge vignetting phenomenon commonly found in ordinary lenses (typically ≤60%).

[0080] In terms of structural design, the system has also undergone several optimizations: Fourth, it achieves high-performance imaging within the compact constraints of a total optical length of 138 mm and a conjugate distance of 210 mm, reducing its volume by more than 15% compared to similar SAM lenses, making it easier to integrate into space-constrained industrial equipment. Fifth, the system provides a long back focal distance of 70.4 mm, reserving ample space for the addition of functional components such as filters and beam splitters, solving the structural rotation limitations caused by the short back focal distance (only about 17.5 mm) of traditional C-mount SAM lenses. Sixth, by precisely matching the 51.7° SAM angle and the 38° object tilt angle, the calibration process is simplified, avoiding the tedious operation of repeatedly adjusting the angle required for conventional SAM lenses. Seventh, the system adopts a 1.6x fixed magnification design, avoiding the potential problems of repeated positioning accuracy and long-term stability in variable magnification systems. Eighth, the system supports a maximum... The 24 mm image circle can perfectly match large target surface sensors of 1.1 inches and above, thereby covering a wider field of view in a single imaging and significantly improving detection efficiency.

[0081] Compared to existing technologies, this optical system demonstrates comprehensive improvements in optical design, imaging performance, and system integration. Its technological advantages do not rely on improvements to a single component, but rather on the optimization of the global architecture and the synergistic effect of key technologies. Specifically, the beneficial effects of this optical system are mainly reflected in the following three aspects: First, at the optical design level, the system employs a global lens combination consisting of twelve spherical lenses. This design effectively avoids the special difficulties in the processing and assembly of aspherical components, especially eliminating the potential performance risks caused by the high sensitivity of aspherical surfaces to shape accuracy in the ultraviolet band, thus improving the system's process feasibility and performance consistency. Second, in terms of imaging performance, at a spatial frequency of 60 lp / mm, the system's modulation transfer function (MTF) value is higher than 0.66 in the central field of view and better than 0.3 in the edge field of view, ensuring high contrast and detail reproduction from the center to the edge of the image. Simultaneously, a relative illumination of over 80% ensures uniform illumination across the entire image plane, eliminating vignetting and providing a reliable foundation for quantitative image analysis. Finally, in terms of system architecture and integration, the system initially designed the optical path with an image-side telecentric structure to ensure that the main ray is perpendicular to the sensor image plane, fundamentally eliminating the magnification change caused by the movement of objects within the depth of field, providing a key guarantee for precise size measurement. In addition, the system achieves high performance within the compact constraints of a total optical length of 138 mm and a conjugate distance of 210 mm, significantly reducing the size compared to similar SAM lenses, and making it easier to integrate into space-constrained industrial inspection equipment.

[0082] In summary, this optical system achieves significant improvements in imaging performance, system stability, integration convenience, and operational efficiency through a series of targeted designs, including global surface design, high relative illumination, optimized structural compactness and back focal space, precise matching of the Sham angle, fixed magnification, and compatibility with large target surface sensors. It meets the needs of modern high-precision machine vision applications.

[0083] Example 4 For reference Figure 25 A description of an electronic device A according to Example 4 of the present invention will be given. Figure 25 This is a schematic diagram of an electronic device for a camera optical system, based on any of the SAM lenses for near-ultraviolet band point light source detection according to Examples 1 to 3.

[0084] exist Figure 25In the figures, reference numeral A2 denotes the main body of the electronic device, and reference numeral A1 denotes any of the SAM lenses for near-ultraviolet band point light source detection according to Examples 1 to 3 (interchangeable lenses). Reference numeral A3 denotes an image sensor (photoelectric conversion element) such as a CMOS image sensor or a CCD image sensor, which is built into the camera body A2 and receives light (the optical image formed by the image optical system A1) from the image optical system A1 and performs photoelectric conversion.

[0085] By using the SAM lens for detecting near-ultraviolet point sources according to any one of Examples 1 to 3 in an electronic device such as a digital still camera, an electronic device with high optical performance based on the SAM lens for detecting near-ultraviolet point sources can be obtained.

[0086] Each example can provide electronic devices with high optical performance.

[0087] Although the invention has been described with reference to exemplary embodiments, it should be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims will be given the broadest interpretation to cover all such modifications and equivalent structures and functions.

Claims

1. A Schamm lens for detection based on a near-ultraviolet point light source, characterized in that, The lens consists of twelve lenses arranged sequentially along an optical axis from the object side to the image side, and all twelve lenses are spherical lenses; wherein... The first lens has positive refractive index, with a flat object-side surface and a convex image-side surface; The second lens has positive refractive index, with a convex object-side surface and a concave image-side surface; The third lens has positive refractive index, with a convex object-side surface and a concave image-side surface; The fourth lens has a positive refractive index, with a convex object-side surface and a concave image-side surface; The fifth lens has positive refractive index, and both the object-side and image-side surfaces are convex. The sixth lens has a negative refractive index, and both the object-side and image-side surfaces are concave. The seventh lens has a negative refractive index, with a convex object-side surface and a concave image-side surface; The eighth lens has a negative refractive index, and both the object-side and image-side surfaces are concave. The ninth lens has positive refractive index, and both the object-side and image-side surfaces are convex. The tenth lens has a negative refractive index, and both the object-side and image-side surfaces are concave. The eleventh lens has positive refractive index, with a concave object side and a convex image side; The twelfth lens has positive refractive index, and both the object-side and image-side surfaces are convex.

2. The Schamm lens for detection based on a near-ultraviolet point light source as described in claim 1, characterized in that, The lens satisfies the following condition: 1.7<Nd1<1.9; 1.7<Nd2<1.8; 1.7<Nd3<1.8; 1.7<Nd4<1.8; 1.5<Nd5<1.6; 1.8<Nd6<1.9; 1.8<Nd7<1.9; 1.8<Nd8<1.9; 1.4<Nd9<1.5;1.8<Nd 10 <1.9;1.6<Nd 11 <1.7;1.9<Nd 12 <2.0; In the formula, Nd1, Nd2, Nd3, Nd4, Nd5, Nd6, Nd7, Nd8, Nd9, Nd 10 、Nd 11 、Nd 12 These represent the refractive indices of the first to twelfth lenses, respectively.

3. The large relative aperture Sham imaging lens for near-ultraviolet band point light source detection as described in claim 2, characterized in that, The lens satisfies the following condition: 45<Vd1<50; 45<Vd2<50; 50<Vd3<55; 50<Vd4<55; 65<Vd5<70; 35<Vd6<40;25<Vd7<30;35<Vd8<40;70<Vd9<75;35<Vd 10 <40;55<Vd 11 <60;35<Vd 12 <40; In the formula, Vd1, Vd2, Vd3, Vd4, Vd5, Vd6, Vd7, Vd8, Vd9, Vd 10 Vd 11 Vd 12 These represent the Abbe numbers of the first to twelfth lenses, respectively.

4. A Schamm lens for detection based on a near-ultraviolet point light source as described in claim 1, characterized in that, The fifth lens and the sixth lens are cemented together to form the first cemented lens group.

5. A Schamm lens for detection based on a near-ultraviolet band point light source as described in claim 4, characterized in that, The lens satisfies the following condition: Nd6- Nd5>0.2; Vd5- Vd6>30; In the formula, Nd5 and Nd6 represent the refractive indices of the fifth and sixth lenses, respectively; Vd5 and Vd6 represent the Abbe numbers of the fifth and sixth lenses, respectively.

6. A Schamm lens for detection based on a near-ultraviolet band point light source as described in claim 4, characterized in that, The eighth lens and the ninth lens are cemented together to form a second cemented lens group.

7. A Schamm lens for detection based on a near-ultraviolet band point light source as described in claim 6, characterized in that, The lens satisfies the following condition: Nd8- Nd9>0.3; Vd9- Vd8>30; In the formula, Nd8 and Nd9 represent the refractive indices of the fifth and sixth lenses, respectively; Vd8 and Vd9 represent the Abbe numbers of the fifth and sixth lenses, respectively.

8. A Schamm lens for detection based on a near-ultraviolet point light source as described in any one of claims 1-7, characterized in that, All twelve lenses are made of glass.

9. An electronic device, comprising: A Sham lens for detection based on a near-ultraviolet point light source according to any one of claims 1-8; and An image sensor is configured to receive the image formed by the Sham lens used for detection based on a near-ultraviolet band point light source.

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