Visible-ultraviolet dual-wavelength projection objective lens and optical system

Abstract

The invention relates to the technical field of optical instruments, and discloses a visible-ultraviolet dual-wavelength projection objective lens and an optical system. Comprising a first lens group with positive focal power, a second lens group with negative focal power, a third lens group with positive focal power and a fourth lens group with positive focal power which are sequentially arranged along the optical axis direction from the object plane to the image plane of the projection objective lens; the projection objective lens further comprises an aperture diaphragm, and the aperture diaphragm is located between two adjacent lenses in the third lens group. Through arrangement of the four lens groups and reasonable matching of positive and negative focal powers, effective correction of chromatic aberration is realized, the imaging quality of the optical system is excellent, and the optical system can be adapted to a high-power large-linewidth deep ultraviolet band light source.

Description

Technical Field

[0001] The invention relates to the technical field of optical instruments, and in particular to a visible-ultraviolet dual-wavelength projection objective lens and an optical system. Background Art

[0002] Micro-LED display panels, as the leader of the new generation of display technology, have attracted much attention in the market and are generally regarded as the future hope of the industry. However, on the road to commercialization, mass transfer technology has become a key bottleneck that needs to be broken through, which seriously restricts the large-scale popularization and application of Micro-LED.

[0003] The essence of mass transfer technology is to precisely control the laser pulses to act on the interfacial adhesion between the laser response layer material and the micro-device, thereby achieving fine shedding and efficient transfer of LED chips. In this process, a uniform light beam needs to pass through a mask with a precise pattern, and the mask pattern is accurately projected to the specified position of the transfer substrate in an imaging manner. To ensure product-level quality, the transfer efficiency and yield rate of this process must meet extremely high standards, which undoubtedly puts forward stringent requirements on the light source with high power, large field of view and high resolution.

[0004] However, there is currently a lack of projection objectives on the market that can adapt to high power and large linewidth in the deep ultraviolet band and have the ability to eliminate chromatic aberration. Summary of the invention

[0005] The present invention aims to improve at least one technical problem in the background technology.

[0006] A first aspect of the present invention provides a visible-ultraviolet dual-wavelength projection objective lens, comprising a first lens group with positive focal power, a second lens group with negative focal power, a third lens group with positive focal power, and a fourth lens group with positive focal power, which are sequentially arranged along the optical axis direction from the object plane to the image plane of the projection objective lens;

[0007] The projection objective lens further comprises an aperture stop, wherein the aperture stop is located between two adjacent lenses in the third lens group.

[0008] The beneficial effects of the embodiments of the first aspect of the present invention are as follows: the projection objective provided by the present invention includes four precisely arranged lens groups; the first lens group performs preliminary chromatic aberration correction with its large positive optical focal length and balances the spherical aberration of the rear optical path; the second lens group effectively balances the field curvature of the front and rear optical paths through its negative optical focal length design and performs preliminary aberration correction capability; the third lens group has positive optical focal length and is responsible for the comprehensive correction of chromatic aberration and aberration, and an aperture diaphragm is cleverly arranged inside the third lens group for limiting the aperture; the fourth lens group, as the last lens group, realizes deep correction of field curvature with its positive optical focal length to ensure high-quality imaging; through the arrangement of the four lens groups and the reasonable combination of positive and negative optical focal lengths, effective correction of chromatic aberration is achieved, the optical system has excellent imaging quality, and can be adapted to high-power and large-linewidth deep ultraviolet band light sources.

[0009] As some sub-solutions of the above technical solution, the first lens group includes a first lens with positive optical power;

[0010] The second lens group includes a second lens with positive focal power, a third lens with positive focal power, a fourth lens with positive focal power, and a fifth lens with negative focal power, which are sequentially arranged along the optical axis direction from the object plane to the image plane;

[0011] The third lens group includes a sixth lens with positive focal power, a seventh lens with negative focal power, an eighth lens with positive focal power, a ninth lens with negative focal power, a tenth lens with positive focal power, an eleventh lens with positive focal power, a twelfth lens with negative focal power, and a thirteenth lens with positive focal power, which are sequentially arranged along the optical axis direction from the object plane to the image plane.

[0012] The fourth lens group includes a fourteenth lens with positive refractive power, a fifteenth lens with positive refractive power, and a sixteenth lens with positive refractive power, which are arranged in sequence from the object plane to the image plane along the optical axis direction;

[0013] The aperture stop is located between the tenth lens and the eleventh lens.

[0014] As some sub-solutions of the above technical solution, the first lens, the third lens, the fourth lens, the fifteenth lens, and the sixteenth lens are all meniscus lenses curved toward the image plane;

[0015] The second lens, the sixth lens, the eighth lens, the tenth lens, the eleventh lens, the thirteenth lens, and the fourteenth lens are all biconvex lenses; the fifth lens, the seventh lens, the ninth lens, and the twelfth lens are all biconcave lenses.

[0016] As some sub-solutions of the above technical solution, the first lens, the fifth lens, the seventh lens, the ninth lens and the twelfth lens are all made of fused silica; the second lens, the third lens, the fourth lens, the sixth lens, the eighth lens, the tenth lens, the eleventh lens, the thirteenth lens, the fourteenth lens, the fifteenth lens and the sixteenth lens are all made of calcium fluoride glass.

[0017] As some sub-solutions of the above technical solution, the lenses of the first lens group, the second lens group, the third lens group and the fourth lens group are all spherical single-piece structures.

[0018] As some sub-solutions of the above technical solution, the object-side field of view radius of the projection objective is 51 mm, and the image-side field of view radius is 10.2 mm.

[0019] As some sub-solutions of the above technical solution, the object-side working distance of the projection objective lens is greater than 150 mm, and the image-side working distance is greater than 30 mm.

[0020] As some sub-solutions of the above technical solution, the numerical aperture of the projection objective lens is 0.20, and the maximum relative distortion is 0.0018%; the object space of the projection objective lens is a telecentric object space, and the image space telecentricity is less than 1.05 mrad.

[0021] As some sub-solutions of the above technical solution, the working wavelength of the projection objective is 248.6±0.4nm and 546±2nm, the object-image conjugate distance is less than 1m, and the magnification is 1 / 5.

[0022] A second aspect of the present invention provides an optical system, comprising the visible-ultraviolet dual-wavelength projection objective lens as described in any one of the above items.

[0023] The optical system according to the embodiment of the second aspect of the present invention also has corresponding beneficial effects because it includes the visible-ultraviolet dual-wavelength projection objective lens of the above technical solution. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0025] Figure 1 A schematic structural diagram of a visible-ultraviolet dual-wavelength projection objective lens provided by an embodiment of the present invention;

[0026] Figure 2 A schematic diagram of the optical path of a visible-ultraviolet dual-wavelength projection objective lens provided in an embodiment of the present invention;

[0027] Figure 3It is the graph of the complex color modulation transfer function of the projection objective lens at a wavelength of 248.6nm;

[0028] Figure 4 It is the graph of the complex color modulation transfer function of the projection objective lens at a wavelength of 546.0nm;

[0029] Figure 5 It is the wavefront diagram of the central field of view of the projection objective at a wavelength of 248.6nm;

[0030] Figure 6 It is the edge field wavefront diagram of the projection objective at a wavelength of 546.0nm;

[0031] Figure 7 It is the wavefront diagram of the central field of view of the projection objective lens at a wavelength of 248.6nm;

[0032] Figure 8 It is the edge field wavefront diagram of the projection objective at a wavelength of 546.0nm;

[0033] Fig. 9 It is the field curvature and distortion diagram of the projection objective lens at a wavelength of 248.6nm;

[0034] Fig.10 It is the field curvature and distortion diagram of the projection objective lens at a wavelength of 546.0nm;

[0035] Fig.11 This is the object telecentricity error diagram of the projection objective at a wavelength of 248.6nm.

[0036] In the accompanying drawings: L1-first lens; L2-second lens; L3-third lens; L4-fourth lens; L5-fifth lens; L6-sixth lens; L7-seventh lens; L8-eighth lens; L9-ninth lens; L10-tenth lens; L11-eleventh lens; L12-twelfth lens; L13-thirteenth lens; L14-fourteenth lens; L15-fifteenth lens; L16-sixteenth lens. DETAILED DESCRIPTION

[0037] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0038] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., and orientations or positional relationships indicated are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0039] In the description of the present invention, the meaning of "several" is an indefinite quantity, the meaning of "multiple" is more than two, "greater than", "less than", "exceed", etc. are understood as not including the number itself, and "above", "below", "within", etc. are understood as including the number itself. If there is a description of the first and the second, it is only for the purpose of distinguishing the technical features, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features. The "and / or" that appears in the full text represents three parallel solutions. For example, A and / or B represents the solution satisfied by A, the solution satisfied by B, or the solution satisfied by both A and B.

[0040] In the description of the present invention, if there is a short sentence containing multiple parallel features, the attributive defines the closest feature, for example: B, C, and E connected to D are arranged on A, which means that B is arranged on A and E is connected to D, and does not constitute a limitation on C; but attributives that indicate the relationship between features, such as "interval arrangement" or "circular arrangement", do not belong to this category. If the word "all" is preceded by an attributive, it means that all features in the short sentence are limited, such as B, C, and D are all arranged on A, which means that B, C, and D are all arranged on A. For a sentence with an omitted subject, the omitted subject is the subject of the previous sentence, that is, B is arranged on A, including C, which means that B is arranged on A and A includes C.

[0041] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention in combination with the specific content of the technical solution.

[0042] Combine the following Figures 1 to 11 Embodiments of the present invention are described.

[0043] Reference Figure 1 and Figure 2 According to a first aspect of the present invention, there is provided a visible-ultraviolet dual-wavelength projection objective lens, comprising a first lens group with positive focal power, a second lens group with negative focal power, a third lens group with positive focal power, and a fourth lens group with positive focal power, which are sequentially arranged along the optical axis direction from the object plane to the image plane of the projection objective lens;

[0044] The projection objective lens further comprises an aperture stop, wherein the aperture stop is located between two adjacent lenses in the third lens group.

[0045] The visible-ultraviolet dual-wavelength projection lens provided in the first embodiment of the present invention is a dual telecentric optical system, and cleverly combines two materials, calcium fluoride and fused quartz. The projection lens is sequentially configured with four lens groups from the object plane to the image plane along the optical axis to achieve high-precision and multi-functional projection requirements. The projection lens can not only work in conjunction with the mask to complete the task of Micro-LED laser mass transfer, but also be combined with an image sensor (such as a CMOS camera) to observe the overall effectiveness of laser transfer.

[0046] Specifically, the projection objective uses the upper mask (or image sensor) as the object plane and the lower response layer material and micro-device interface as the image plane. The four mirror groups each have their own functions: the first mirror group, with its large positive optical power, helps to correct chromatic aberration, and more importantly, balances the spherical aberration of the rear optical path; the second mirror group, through its negative optical power design, effectively balances the field curvature of the front and rear optical paths, and has the ability to correct aberrations such as chromatic aberration, coma and spherical aberration; the third mirror group, with a more complex structure, undertakes the comprehensive correction task from elementary to advanced aberrations (including chromatic aberration, spherical aberration, coma, astigmatism, field curvature, etc.), and an aperture stop is cleverly set inside to limit the aperture; the fourth mirror group, with its positive optical power, focuses on the deep correction of field curvature to ensure high-quality imaging.

[0047] In view of the difference in optical properties between visible light and deep ultraviolet bands, especially the lack of available optical glue and high-transmittance materials in the deep ultraviolet band, the projection objective lens of the first embodiment of the present invention adopts fused quartz and calcium fluoride, two materials with high transmittance in the deep ultraviolet band. The design is optimized for the two wavelengths of 248.6nm (for mass transfer) and 546.0nm (for monitoring). By carefully matching optical materials with different Abbe numbers and alternating combinations of positive and negative optical powers, not only the wave aberration of the system is effectively corrected, but also the chromatic aberration caused by the large line width light source is significantly reduced, thereby improving the imaging quality of the projection objective lens, achieving finer resolution, and further enhancing the quality and efficiency of laser mass transfer.

[0048] Specifically, the first lens group includes a first lens L1 with positive refractive power; the second lens group includes a second lens L2 with positive refractive power, a third lens L3 with positive refractive power, a fourth lens L4 with positive refractive power, and a fifth lens L5 with negative refractive power, which are sequentially arranged from the object plane to the image plane along the optical axis direction; the third lens group includes a sixth lens L6 with positive refractive power, a seventh lens L7 with negative refractive power, an eighth lens L8 with positive refractive power, and a fifth lens L9 with negative refractive power, which are sequentially arranged from the object plane to the image plane along the optical axis direction. A ninth lens L9 with negative focal power, a tenth lens L10 with positive focal power, an eleventh lens L11 with positive focal power, a twelfth lens L12 with negative focal power, and a thirteenth lens L13 with positive focal power; the fourth lens group includes a fourteenth lens L14 with positive focal power, a fifteenth lens L15 with positive focal power, and a sixteenth lens L16 with positive focal power which are arranged in sequence from the object plane to the image plane along the optical axis direction; and the aperture stop is located between the tenth lens L10 and the eleventh lens L11.

[0049] In the first lens group, the first lens L1 is the starting lens of the positive light projection objective lens. The first lens L1 is mainly responsible for chromatic aberration correction and balancing the spherical aberration of the rear optical path. Its positive focal length helps to converge light and provide suitable incident light conditions for subsequent lens groups.

[0050] In the second lens group, the second lens L2 to the fourth lens L4 are designed with continuous positive focal power, which helps to enhance the convergence ability of the system and participates in the preliminary correction of aberrations such as chromatic aberration and field curvature; the fifth lens L5, as the last lens of the second lens group, has a negative focal power design to balance the field curvature of the front and rear light paths, and to further correct aberrations such as chromatic aberration and coma.

[0051] In the third lens group, the sixth lens L6 to the thirteenth lens L13 include multiple alternating designs of positive and negative optical power. Such a design can more finely correct various aberrations, including primary and higher-order aberrations such as chromatic aberration, spherical aberration, coma, astigmatism, and field curvature. It should be noted that the alternation of positive and negative optical power helps to introduce more correction freedom into the system, thereby achieving more comprehensive control of aberrations.

[0052] In the fourth lens group, the continuous positive focal power design of the three lenses from the fourteenth lens L14 to the sixteenth lens L16 further enhances the system's convergence capability and focuses on the depth correction of field curvature. As the last lens group of the projection objective, the fourth lens group is crucial to ensuring high-quality imaging.

[0053] The aperture stop is located between the tenth lens L10 and the eleventh lens L11, and its setting helps to limit the incident angle of light, reduce stray light and aberrations, and improve imaging quality.

[0054] Specifically, the first lens L1, the third lens L3, the fourth lens L4, the fifteenth lens L15, and the sixteenth lens L16 are all meniscus lenses curved toward the image plane; the second lens L2, the sixth lens L6, the eighth lens L8, the tenth lens L10, the eleventh lens L11, the thirteenth lens L13, and the fourteenth lens L14 are all biconvex lenses; the fifth lens L5, the seventh lens L7, the ninth lens L9, and the twelfth lens L12 are all biconcave lenses.

[0055] The meniscus lens has a convex side and a concave side. Its design of bending toward the image plane enables it to provide a smaller positive optical focal length. The meniscus lens is mainly used to correct field curvature in projection objectives. Its special shape and optical focal length distribution help balance the imaging performance of the system.

[0056] The double convex lens has convex surfaces on both sides, which can provide large positive focal length and enhance the convergence ability of the system. The double convex lens is mainly used in projection objective lenses to enhance the convergence effect of light, and at the same time participates in the correction of aberrations such as chromatic aberration and spherical aberration.

[0057] Biconcave lenses are concave on both sides, providing a large negative optical power that helps balance the positive optical power produced by other lenses in the system, thereby achieving further correction of aberrations.

[0058] Specifically, the first lens L1, the fifth lens L5, the seventh lens L7, the ninth lens L9 and the twelfth lens L12 are all made of fused silica; the second lens L2, the third lens L3, the fourth lens L4, the sixth lens L6, the eighth lens L8, the tenth lens L10, the eleventh lens L11, the thirteenth lens L13, the fourteenth lens L14, the fifteenth lens L15 and the sixteenth lens L16 are all made of calcium fluoride glass.

[0059] Fused quartz is a material with high light transmittance, low expansion coefficient and low dispersion, which is particularly suitable for optical design in the deep ultraviolet and visible light bands; the lens is made of fused quartz material, which helps to reduce chromatic aberration and improve imaging quality; calcium fluoride glass has excellent light transmittance and low dispersion characteristics in the ultraviolet band, which is an ideal choice for deep ultraviolet optical design; the lens is made of calcium fluoride glass material, which helps to ensure the imaging performance of the system in the deep ultraviolet band. The internal transmittance of the fused quartz glass material and calcium fluoride glass material used in the projection objective lens exceeds 99% at 248.6nm and 546nm.

[0060] Specifically, the lenses of the first lens group, the second lens group, the third lens group and the fourth lens group are all spherical single-piece structures.

[0061] It should be noted that optical systems in the visible light band usually use cemented lenses with different Abbe numbers to eliminate chromatic aberration, but there is no optical glue available in the deep ultraviolet band. Therefore, all lenses of the projection objective use a separate independent spherical single-piece lens structure without cemented lenses; and no aspherical design is used, which reduces the difficulty of assembly and processing costs.

[0062] Specifically, the object-side field of view radius of the projection objective is 51 mm, and the image-side field of view radius is 10.2 mm.

[0063] The object field radius is 51mm and the image field radius is 10.2mm, so the projection objective can meet the requirements of large field of view.

[0064] Specifically, the object-side working distance of the projection objective is greater than 150 mm, and the image-side working distance is greater than 30 mm.

[0065] The object side working distance of the projection objective is greater than 150mm, so that the projection objective itself has sufficient adjustment space; the image side working distance is greater than 30mm, which can ensure that the material on the image side has sufficient movement and adjustment space.

[0066] Specifically, the image-side numerical aperture of the projection objective is 0.20, and the maximum relative distortion is 0.0018%; the object-side of the projection objective is a telecentric object space, and the image-side telecentricity is less than 1.05 mrad.

[0067] High numerical aperture and low distortion enable the projection objective to meet the requirements of high-power laser passage; the reverse optical path design may help reduce aberrations and thus improve resolution; low telecentricity means that the imaging is more stable and is not affected by slight changes in the position of the object or detector.

[0068] Specifically, the working wavelengths of the projection objective are 248.6±0.4nm and 546±2nm, the object-image conjugate distance is less than 1m, and the magnification is 1 / 5.

[0069] The central working wavelength is 248.6±0.4nm, which is used in the laser mass transfer process. Deep ultraviolet light has the characteristics of short wavelength and high energy, and can accurately cut, etch or transfer tiny structures. By precisely controlling the beam of this wavelength, high-precision laser mass transfer can be achieved, improving production efficiency and qualified rate; the visible light wavelength is 546±2nm, which is mainly used in conjunction with the imaging system to feedback data in real time, monitor the wavefront and focal plane position of the optical system, and combine with the correction system to correct the system wavefront and adjust the image plane in real time to prevent the image quality from deteriorating due to changes in environmental parameters, affecting the quality of laser mass transfer.

[0070] The various optical components of the projection objective provided in the embodiment of the first aspect of the present invention meet the conditions of Table 1 and Table 2; Table 1 is the constraint parameters of the projection objective; Table 2 is the design parameters of the projection objective.

[0071] Table 1

[0072]

[0073] Table 2

[0074]

[0075]

[0076] It should be noted that the object distance in Table 2 is the data when the projection objective lens has a central wavelength of 248.6 nm. When the central wavelength is 546.0 nm, the object distance is 172.658 mm.

[0077] Under the conditions of working wavelength range, object field radius, image numerical aperture and other parameters in Table 1, according to the analysis and calculation of professional optical design software Opticstudio, the aberration correction degree of the projection objective is as follows:

[0078] Reference Figure 3 and Figure 4 , Figure 3 and Figure 4 The polychromatic modulation transfer function (MTF) of the projection objective at 248.6 nm and 546.0 nm, respectively, is shown, which is close to the diffraction limit.

[0079] Reference Figure 5 and Figure 6 , Figure 5 , Figure 6 It is the wavefront diagram when the central wavelength λ of the projection objective optical system is 248.6nm. The RMS wavefront value of the central field of view is 0.0174λ, and the RMS wavefront value of the edge field of view is 0.0730λ; refer to Figure 7 and Figure 8 , Figure 7 , Figure 8 It is the wavefront diagram of the projection objective lens of this embodiment at the central wavelength λ=546.0nm. The RMS wavefront value of the central field of view is 0.0504λ, and the RMS wavefront value of the edge field of view is 0.0454λ. Figures 5 to 8 This indicates that the wave aberration of the projection objective is well corrected, the imaging quality is close to perfect imaging, and the chromatic aberration between wavelengths is well corrected.

[0080] Reference Fig. 9 and Fig.10 , Fig. 9 and Fig.10 It is the field curvature and distortion diagram of the projection objective. At the central wavelength of 248.6nm, the field curvature is less than 8.5μm, and the maximum relative distortion is 0.0018%, corresponding to a distortion of 184nm. The field curvature and distortion have been well corrected.

[0081] Reference Fig.11 , Fig.11 It is the object-side telecentricity error when the projection objective lens works at a central wavelength of 248.6nm, of which the maximum value is 1.05mrad, and the image-side telecentricity has been well corrected.

[0082] From the above, it can be seen that the visible-ultraviolet dual-wavelength projection objective provided by the embodiment of the first aspect of the present invention has excellent imaging quality, can adapt to high-power and large-linewidth deep ultraviolet band light sources, and has the ability to eliminate chromatic aberration.

[0083] An optical system in an embodiment of the second aspect of the present invention includes the visible-ultraviolet dual-wavelength projection objective lens described in the above embodiment.

[0084] The optical system according to the embodiment of the second aspect of the present invention also has corresponding beneficial effects because it includes the visible-ultraviolet dual-wavelength projection objective lens of the above technical solution.

[0085] The preferred embodiments of the present invention are described in detail above, but the present disclosure is not limited to the embodiments. Those skilled in the art may make various equivalent modifications or substitutions without violating the spirit of the present invention. These equivalent modifications or substitutions are all included in the scope defined by the claims of the present disclosure.

Claims

1. A visible-ultraviolet dual-wavelength projection objective lens, characterized in that: The projection lens comprises a first lens group with positive focal power, a second lens group with negative focal power, a third lens group with positive focal power and a fourth lens group with positive focal power, which are sequentially arranged along the optical axis direction from the object plane to the image plane of the projection lens; The projection objective lens further comprises an aperture stop, wherein the aperture stop is located between two adjacent lenses in the third lens group.

2. The visible-ultraviolet dual-wavelength projection objective lens according to claim 1, characterized in that: The first lens group comprises a first lens (L1) having positive optical power; The second lens group comprises a second lens (L2) with positive focal power, a third lens (L3) with positive focal power, a fourth lens (L4) with positive focal power, and a fifth lens (L5) with negative focal power, which are sequentially arranged along the optical axis direction from the object plane to the image plane; The third lens group includes a sixth lens (L6) with positive focal power, a seventh lens (L7) with negative focal power, an eighth lens (L8) with positive focal power, a ninth lens (L9) with negative focal power, a tenth lens (L10) with positive focal power, an eleventh lens (L11) with positive focal power, a twelfth lens (L12) with negative focal power, and a thirteenth lens (L13) with positive focal power, which are sequentially arranged from the object plane to the image plane along the optical axis direction; the fourth lens group includes a fourteenth lens (L14) with positive focal power, a fifteenth lens (L15) with positive focal power, and a sixteenth lens (L16) with positive focal power, which are sequentially arranged from the object plane to the image plane along the optical axis direction; The aperture stop is located between the tenth lens (L10) and the eleventh lens (L11).

3. The visible-ultraviolet dual-wavelength projection objective lens according to claim 2, characterized in that: The first lens (L1), the third lens (L3), the fourth lens (L4), the fifteenth lens (L15), and the sixteenth lens (L16) are all meniscus lenses curved toward the image plane; The second lens (L2), the sixth lens (L6), the eighth lens (L8), the tenth lens (L10), the eleventh lens (L11), the thirteenth lens (L13), and the fourteenth lens (L14) are all biconvex lenses; The fifth lens (L5), the seventh lens (L7), the ninth lens (L9), and the twelfth lens (L12) are all biconcave lenses.

4. The visible-ultraviolet dual-wavelength projection objective lens according to claim 2, characterized in that: The first lens (L1), the fifth lens (L5), the seventh lens (L7), the ninth lens (L9) and the twelfth lens (L12) are all made of fused silica; the second lens (L2), the third lens (L3), the fourth lens (L4), the sixth lens (L6), the eighth lens (L8), the tenth lens (L10), the eleventh lens (L11), the thirteenth lens (L13), the fourteenth lens (L14), the fifteenth lens (L15) and the sixteenth lens (L16) are all made of calcium fluoride glass.

5. The visible-ultraviolet dual-wavelength projection objective lens according to claim 1, characterized in that: The lenses of the first lens group, the second lens group, the third lens group and the fourth lens group are all spherical single-piece structures.

6. The visible-ultraviolet dual-wavelength projection objective lens according to claim 1, characterized in that: The object-side field of view radius of the projection objective lens is 51 mm, and the image-side field of view radius is 10.2 mm.

7. The visible-ultraviolet dual-wavelength projection objective lens according to claim 1, characterized in that: The object side working distance of the projection objective lens is greater than 150 mm, and the image side working distance is greater than 30 mm.

8. The visible-ultraviolet dual-wavelength projection objective lens according to claim 1, characterized in that: The numerical aperture of the projection objective lens is 0.20, and the maximum relative distortion is 0.0018%; the object side of the projection objective lens is a telecentric object space, and the image side telecentricity is less than 1.05 mrad.

9. The visible-ultraviolet dual-wavelength projection objective lens according to claim 1, characterized in that: The working wavelength of the projection objective lens is 248.6±0.4nm and 546±2nm, the object-image conjugate distance is less than 1m, and the magnification is 1 / 5.

10. An optical system, characterized in that: The invention comprises the visible-ultraviolet dual-wavelength projection objective lens as described in any one of claims 1 to 9.

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