A visible-ultraviolet dual-wavelength projection objective lens and optical system

Abstract

The present invention relates to the technical field of optical instruments and discloses a visible-ultraviolet dual-wavelength projection objective lens and an optical system. The optical system comprises a first lens group with positive optical power, a second lens group with negative optical power, a third lens group with positive optical power, and a fourth lens group with positive optical power, which are arranged in sequence along the optical axis of the projection objective lens from the object plane to the image plane. The projection objective lens also includes an aperture stop located between two adjacent lenses in the third lens group. Through the arrangement of the four lens groups and the rational combination of positive and negative optical powers, effective correction of chromatic aberration is achieved, the optical system has excellent imaging quality, and is adaptable to high-power, large-linewidth deep ultraviolet light sources.

Description

Technical Field

[0001] The present 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 a leading next-generation display technology, have attracted considerable attention for their market prospects and are widely considered the industry's future hope. However, on the road to commercialization, mass transfer technology has become a key bottleneck that urgently needs to be overcome, seriously restricting the large-scale popularization and application of Micro-LED.

[0003] The essence of mass transfer technology lies in precisely controlling laser pulses to influence the interfacial adhesion between the laser-responsive layer material and the microdevice, thereby achieving precise removal and efficient transfer of LED chips. This process requires a uniform light beam to pass through a precisely patterned mask, projecting the mask pattern onto the designated location on the transfer substrate using imaging. To ensure product-grade quality, this process requires extremely high transfer efficiency and yield rates, placing stringent demands on the light source for high power, a large field of view, and high resolution.

[0004] However, the current market lacks projection objectives 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 embodiment of the present invention provides a visible-ultraviolet dual-wavelength projection objective lens, comprising a first lens group with positive optical power, a second lens group with negative optical power, a third lens group with positive optical power, and a fourth lens group with positive optical power, which are sequentially arranged along the optical axis of the projection objective lens from the object plane to the image plane;

[0007] The projection objective lens further includes an aperture stop, which 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 power 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 power design, and performs preliminary aberration correction capability; the third lens group has positive optical power and is responsible for the comprehensive correction of chromatic aberration and aberration, and an aperture stop is cleverly arranged inside it for limiting the aperture; the fourth lens group, as the last lens group, uses its positive optical power to achieve deep correction of field curvature to ensure high-quality imaging; through the arrangement of the four lens groups and the reasonable combination of positive and negative optical power, 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 refractive power, a third lens with positive refractive power, a fourth lens with positive refractive power, and a fifth lens with negative refractive power, which are arranged in sequence from the object plane to the image plane along the optical axis.

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

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

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

[0022] A second embodiment of the present invention provides an optical system comprising any one of the visible-ultraviolet dual-wavelength projection objective lenses described above.

[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 readily understood from the following description of the embodiments with reference to the accompanying 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 3This is the polychromatic modulation transfer function diagram of the projection objective lens at a wavelength of 248.6nm;

[0028] Figure 4 is the polychromatic modulation transfer function diagram 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 lens at a wavelength of 248.6nm;

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

[0033] Figure 9 The field curvature and distortion diagram of the projection objective lens at a wavelength of 248.6nm;

[0034] Figure 10 The field curvature and distortion diagram of the projection objective lens at a wavelength of 546.0nm;

[0035] Figure 11 This is the object space telecentricity error diagram of the projection objective lens 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] The following describes embodiments of the present invention in detail. Examples of the embodiments 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 intended only to explain the present invention and are not to be construed 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., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings. They 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. Therefore, they cannot be understood as limitations on the present invention.

[0039] In the description of the present invention, "several" means an indefinite quantity, "multiple" means more than two, "greater than," "less than," and "exceed" are understood to exclude the number itself, and "above," "below," and "within" are understood to include the number itself. The use of "first" and "second" is solely for the purpose of distinguishing technical features and should not be understood to indicate or imply relative importance, or to implicitly indicate the number or order of the technical features indicated. "And / or" throughout the text represents three parallel solutions. For example, "A and / or B" means a solution where A satisfies, a solution where B satisfies, or a solution where both A and B satisfy.

[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 are arranged on A, and are connected to D" means that B is arranged on A and E is connected to D, and does not constitute a limitation on C. However, attributives that express the relationship between features, such as "spaced arrangement" or "circular arrangement", do not fall into this category. If the word "all" is preceded by an attributive, it means that all features in the short sentence are limited. For example, "B, C, and D are all arranged on A" means that B, C, and D are all arranged on A. In 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" 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, and connecting 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 based on the specific content of the technical solution.

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

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

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

[0045] The visible-UV dual-wavelength projection objective lens provided in the first embodiment of the present invention is a bi-telecentric optical system that cleverly integrates calcium fluoride and fused quartz. The projection objective lens is configured with four lens groups along the optical axis, from the object plane to the image plane, to achieve high-precision and multifunctional projection requirements. The projection objective lens not only works in conjunction with a mask to perform micro-LED laser mass transfer tasks, but can also be combined with an image sensor (such as a CMOS camera) to monitor the overall effectiveness of the 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 microdevice interface as the image plane. Each of the four lens groups performs its own function: the first lens group, with its large positive optical power, helps correct chromatic aberration and, more importantly, balances the spherical aberration of the rear optical path; the second lens 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 lens group, with its more complex structure, undertakes the comprehensive correction task of from elementary to advanced aberrations (including chromatic aberration, spherical aberration, coma, astigmatism, field curvature, etc.), and also cleverly sets an aperture stop inside it to limit the aperture; the fourth lens group, with its positive optical power, focuses on deep correction of field curvature to ensure high-quality imaging.

[0047] Given the differences in optical properties between visible light and deep ultraviolet wavelengths, particularly the lack of available optical adhesives and high-transmittance materials in the deep ultraviolet, the projection objective lens of the first embodiment of the present invention utilizes fused quartz and calcium fluoride, two materials with high transmittance in the deep ultraviolet. The lens is optimized for wavelengths of 248.6 nm (for mass transfer) and 546.0 nm (for monitoring). By carefully matching optical materials with different Abbe numbers and alternating positive and negative optical powers, the system's wavefront aberration is effectively corrected while significantly reducing the effects of chromatic aberration caused by wide-linewidth light sources. This improves the imaging quality of the projection objective lens, achieves finer resolution, and further enhances 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 arranged in sequence from the object plane to the image plane along the optical axis; 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 ninth lens L9 with negative refractive power, which are arranged in sequence from the object plane to the image plane along the optical axis. The fourth lens group comprises a ninth lens L9 with negative optical power, a tenth lens L10 with positive optical power, an eleventh lens L11 with positive optical power, a twelfth lens L12 with negative optical power, and a thirteenth lens L13 with positive optical power. The fourth lens group comprises a fourteenth lens L14 with positive optical power, a fifteenth lens L15 with positive optical power, and a sixteenth lens L16 with positive optical power, arranged in sequence from the object plane to the image plane along the optical axis. An aperture stop is located between the tenth lens L10 and the eleventh lens L11.

[0049] In the first lens group, the first lens, L1, serves as the starting lens for the positive projection objective. It primarily corrects chromatic aberration and balances spherical aberration in the rear optical path. Its positive refractive power helps converge light, providing 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 system's convergence ability and at the same time 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 optical paths, and further correct aberrations such as chromatic aberration and coma.

[0051] In the third lens group, the sixth lens element L6 to the thirteenth lens element L13 include multiple alternating positive and negative optical powers. This 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 powers helps to introduce more correction degrees of freedom in 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 (14th lens L14 to 16th lens L16) further enhances the system's convergence capability and focuses on deep 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 element L10 and the eleventh lens element L11. Its arrangement helps to limit the incident angle of light, reduce stray light and aberrations, and improve image 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; and 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, which is curved 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 to balance the imaging performance of the system.

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

[0057] Biconcave lenses, with concave surfaces on both sides, provide 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, a material with high transmittance, low thermal expansion coefficient, and low dispersion, is particularly suitable for optical design in the deep ultraviolet and visible light bands. Lenses made of fused quartz help reduce chromatic aberration and improve imaging quality. Calcium fluoride glass, with its excellent transmittance and low dispersion in the UV band, is an ideal choice for deep ultraviolet optical design. Lenses made of calcium fluoride glass help ensure system imaging performance in the deep ultraviolet band. The fused quartz and calcium fluoride glass materials used in projection objectives have internal transmittances exceeding 99% at 248.6nm and 546nm, respectively.

[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 composed of different Abbe numbers to eliminate chromatic aberration, but there is no available optical cement in the deep ultraviolet band. Therefore, all lenses of the projection objective lens adopt a separate independent spherical single-piece lens structure, without cemented lenses; and no aspheric design is used, which reduces assembly difficulty 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 side field of view radius is 51mm and the image side field of view radius is 10.2mm, so the projection objective lens meets the requirements of a large field of view.

[0064] Specifically, 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.

[0065] The object side working distance of the projection objective is greater than 150mm, which allows the projection objective itself to have 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, thereby improving 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 lens 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 operating wavelength is 248.6±0.4nm and is used in laser mass transfer processes. Deep ultraviolet light, with its short wavelength and high energy, is capable of precisely cutting, etching, or transferring tiny structures. Precisely controlling this wavelength beam enables high-precision laser mass transfer, improving production efficiency and yield. The visible light wavelength is 546±2nm and is primarily used in conjunction with an imaging system to provide real-time data feedback, monitor the optical system's wavefront and focal plane position, and, in conjunction with a correction system, to correct the system's wavefront and adjust the image plane in real time, preventing degradation of imaging quality caused by changes in environmental parameters that could affect the quality of laser mass transfer.

[0070] The various optical components of the projection objective lens 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 lens; Table 2 is the design parameters of the projection objective lens.

[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 degree of aberration correction of the projection objective lens 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 is shown, respectively, which is close to the diffraction limit.

[0079] Reference Figure 5 and Figure 6 , Figure 5 、 Figure 6 This is the wavefront diagram of the projection objective optical system at the central wavelength λ = 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 This 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 shows that the wavefront 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 Figure 9 and Figure 10 , Figure 9 and Figure 10 This is a diagram of the field curvature and distortion 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 Figure 11 , Figure 11 It is the object space telecentricity error of the projection objective lens when the central working wavelength is 248.6nm. The maximum value is 1.05mrad, and the image space telecentricity has been well corrected.

[0082] From the above, it can be seen that the visible-ultraviolet dual-wavelength projection objective lens 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 above specifically describes the preferred embodiments of the present invention, 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 objective lens comprises a first lens group with positive optical power, a second lens group with negative optical power, a third lens group with positive optical power, and a fourth lens group with positive optical power, which are sequentially arranged along the optical axis of the projection objective lens from the object plane to the image plane; the projection objective lens has four lens groups; The projection objective lens further includes an aperture stop, wherein the aperture stop is located between two adjacent lenses in the third lens group; The first lens group is composed of a first lens (L1) with positive optical power; The second lens group is composed of 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 arranged in sequence from the object plane to the image plane of the projection objective lens along the optical axis of the projection objective lens; The third lens group is composed of 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 arranged in sequence from the object plane to the image plane along the optical axis of the projection objective lens. The fourth lens group is composed of a fourteenth lens (L14) with positive refractive power, a fifteenth lens (L15) with positive refractive power, and a sixteenth lens (L16) with positive refractive power, which are arranged in sequence from the object plane to the image plane of the projection objective lens along the optical axis of the projection objective lens; The aperture stop is located between the tenth lens (L10) and the eleventh lens (L11); The design parameters of the projection objective are as follows: 。 2. The visible-ultraviolet dual-wavelength projection objective lens according to claim 1, 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.

3. The visible-ultraviolet dual-wavelength projection objective lens according to claim 1, wherein: 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.

4. The visible-ultraviolet dual-wavelength projection objective lens according to claim 1, wherein: 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.

5. The visible-ultraviolet dual-wavelength projection objective lens according to claim 1, wherein: 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.

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

7. An optical system, characterized in that: The visible-ultraviolet dual-wavelength projection objective lens comprises the one described in any one of claims 1 to 6.

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