Large-field-of-view dispersion microscope objective

Abstract

The invention provides a large-field-of-view dispersion microscope objective, and relates to the technical field of microscopic imaging and wafer bonding, and the large-field-of-view dispersion microscope objective sequentially comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens and an eighth lens from the emergent side to the object side. Wherein the first lens and the second lens are glued to form a group of doublet lenses. The dispersion microscope objective is a 5X objective, the object space view field is 8.8 mm, the dispersion microscope objective is used in a high-precision chip and wafer bonding visual system, adjacent mark points of a chip and a wafer needing to be bonded can be observed at the same time through the microscope objective by means of dispersion characteristics, due to the fact that real-time observation can be achieved in the bonding process, the bonding precision is greatly improved, and the bonding precision is greatly improved. Therefore, by using the large-view-field dispersion microscope objective, the precision and efficiency of a chip and wafer bonding system can be greatly improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of microscopic imaging and wafer bonding, and particularly relates to a large field of view dispersive microscopic objective. BACKGROUND

[0002] The alignment accuracy is the most critical factor to ensure the quality of wafer bonding in wafer bonding equipment, and the vision system plays a decisive role. In high-precision bonding equipment, near-infrared optical systems are often used. The near-infrared band can penetrate the semiconductor wafer to directly observe the mark points. One of the main directions of bonding application is wafer to wafer bonding (W2W), which can mark points on the edge of each wafer, and then use two sets of vision systems to bond the edge mark points of the wafers. In the bonding process, the infrared system is first used to observe the mark points on the lower surface of the upper wafer, and then the piezoelectric ceramic driver is used to move the optical system as a whole downward to observe the mark points on the upper surface of the lower wafer. The positions of the mark points of the upper wafer and the lower wafer are recorded, and the position of the lower wafer is adjusted by a high-precision displacement platform to move the mark points of the lower wafer to the position of the mark points of the upper wafer. In this process, since the infrared system can observe the position of the mark points, the bonding accuracy is improved.

[0003] Another important application in bonding is die to wafer bonding (D2W), which bonds the chip to the wafer. Two mark points are usually needed for alignment at the same time, that is, two mark points on the wafer and two mark points on the chip are aligned at the same time. Unlike W2W, the volume of the chip is usually very small, and the distance between the two mark points is in the range of several millimeters. For this range, the conventional high-power microscope (high-power microscope system has a small field of view on the object side, and the infrared camera 10X objective lens has only 0.8mm) system cannot cover the two mark points, but the interval of the two mark points cannot be arranged with two sets of systems, so it is impossible to align the two mark points with an interval of several millimeters at the same time. SUMMARY

[0004] Therefore, the embodiment of the present application provides a large field of view dispersion microscope objective, which solves the problem of how to simultaneously align two mark points on a wafer with two mark points on a chip, especially when the interval of the two marks exceeds the detection range of a single vision system. The dispersion microscope objective is a 5X objective, which is matched with a specially designed 2X barrel lens to achieve a 10X magnification effect, and the object field of view is 8.8mm, which is used for high-precision chip and wafer bonding, i.e., a D2W bonding vision system. The dispersion microscope objective can simultaneously observe the adjacent mark points of the chip and wafer to be bonded by using the dispersion characteristics, and the bonding process can be observed in real time, so that the precision and efficiency of the D2W bonding system can be greatly improved by using the large field of view dispersion microscope objective.

[0005] The embodiment of the present application provides the following technical scheme: a large field of view dispersion microscope objective, the dispersion microscope objective sequentially comprises, from an exit side to an object side: a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens and an eighth lens; wherein the first lens and the second lens are glued into a set of double-glued lenses;

[0006] and the following relationship is met: 0.001≤Δλ / ΔWD≤0.002;

[0007] 20nm≤Δλ;

[0008] 20μm≤ΔWD, WD(λ min )≥35mm;

[0009] 2y=8.8mm;

[0010] NA≥0.35;

[0011] wherein, λ min is the shortest working wavelength of the dispersion microscope objective, λ max is the longest working wavelength of the dispersion microscope objective, Δλ=λ max -λ min ; WD(λ max ) is the back focal distance corresponding to the longest working wavelength, WD(λ min ) is the back focal distance corresponding to the shortest working wavelength, ΔWD=WD(λ max )-WD(λ min ), y is the half field of view, and NA is the numerical aperture of the dispersion microscope objective.

[0012] According to an embodiment of the present application, the shortest working wavelength λ min of the dispersion microscope objective is 1100nm, the longest working wavelength λ max of the dispersion microscope objective is 1300nm, and 100μm≤ΔWD≤200μm.

[0013] According to an embodiment of the present application, the focal length of the dispersive microscope objective is f, the numerical aperture of the dispersive microscope objective is NA, and the following relation is satisfied:

[0014] 12≤f*NA≤16.

[0015] According to an embodiment of the present application, the focal length of the dispersive microscope objective is f = 40 mm, and the numerical aperture of the dispersive microscope objective is NA = 0.35.

[0016] According to an embodiment of the present application, the focal length of the first lens and the second lens glued together as a doublet is f 12 , the focal length of the third lens is f3, the focal length of the fourth lens is f4, the focal length of the fifth lens is f5, the focal length of the sixth lens is f6, the focal length of the seventh lens is f7, the focal length of the eighth lens is f8, the focal length of the dispersive microscope objective is f, and the following relation is satisfied:

[0017] -1.20≤f 12 / f≤-0.90;

[0018] 2.60≤f3 / f≤3.50;

[0019] 2.30≤f4 / f≤3.15;

[0020] 2.00≤f5 / f≤2.75;

[0021] 1.90≤f6 / f≤2.60;

[0022] -0.90≤f7 / f≤-0.65;

[0023] 1.40≤f8 / f≤1.85.

[0024] According to an embodiment of the present application, the first face curvature radius of the first lens is r1, the glued face curvature radius of the second face of the first lens and the first face of the second lens is r2, the second face curvature radius of the second lens is r3, the first face curvature radius of the third lens is r4, the second face curvature radius of the third lens is r5, the first face curvature radius of the fourth lens is r6, the second face curvature radius of the fourth lens is r7, the first face curvature radius of the fifth lens is r8, the second face curvature radius of the fifth lens is r9, the first face curvature radius of the sixth lens is r 10 , the second face curvature radius of the sixth lens is r 11 , the first face curvature radius of the seventh lens is r 12 , the second face curvature radius of the seventh lens is r 13 , the first face curvature radius of the eighth lens is r14 a second radius of curvature of the eighth lens is r 15 , and satisfies the following relationship:

[0025] 3.15 ≤ (r1+r2) / (r1-r2) ≤ 4.25;

[0026] -1.30 ≤ (r2+r3) / (r2-r3) ≤ -1.00;

[0027] 1.20 ≤ (r4+r5) / (r4-r5) ≤ 1.60;

[0028] 1.50 ≤ (r6+r7) / (r6-r7) ≤ 2.00;

[0029] -2.40 ≤ (r8+r9) / (r8-r9) ≤ -1.80;

[0030] -2.20 ≤ (r 10 +r 11 ) / (r 10 -r 11 ) ≤ -1.60;

[0031] 1.10 ≤ (r 12 +r 13 ) / (r 12 -r 13 ) ≤ 1.50;

[0032] -2.00 ≤ (r 14 +r 15 ) / (r 14 -r 15 ) ≤ -1.50.

[0033] According to an embodiment of the present application, the thickness of the first lens is d1, the thickness of the second lens is d2, the thickness of the third lens is d3, the thickness of the fourth lens is d4, the thickness of the fifth lens is d5, the thickness of the sixth lens is d6, the thickness of the seventh lens is d7, the thickness of the eighth lens is d8, the total length of the chromatic dispersion microscope objective from the first lens to the focusing position is TTL, and the following relationship is satisfied:

[0034] 0.06 ≤ d1 / TTL ≤ 0.08;

[0035] 0.04 ≤ d2 / TTL ≤ 0.06;

[0036] 0.07 ≤ d3 / TTL ≤ 0.10;

[0037] 0.07 ≤ d4 / TTL ≤ 0.10;

[0038] 0.07≤d5 / TTL≤0.10;

[0039] 0.08≤d6 / TTL≤0.10;

[0040] 0.04≤d7 / TTL≤0.06;

[0041] 0.05≤d8 / TTL≤0.07.

[0042] According to an embodiment of the present application, the interval between the first lens and the second lens formed by cementing the first lens and the second lens into a double cemented lens is t1, the interval between the third lens and the fourth lens is t2, the interval between the fourth lens and the fifth lens is t3, the interval between the fifth lens and the sixth lens is t4, the interval between the sixth lens and the seventh lens is t5, the interval between the seventh lens and the eighth lens is t6, the total length of the chromatic dispersion microscope objective from the first lens to the focus position is TTL, and the following relationships are satisfied:

[0043] 0.07≤t1 / TTL≤0.10;

[0044] 0.01≤t2 / TTL≤0.02;

[0045] 0.005≤t3 / TTL≤0.01;

[0046] 0.04≤t4 / TTL≤0.06;

[0047] 0.01≤t5 / TTL≤0.02;

[0048] 0.03≤t6 / TTL≤0.04.

[0049] According to an embodiment of the present application, the total length of the chromatic dispersion microscope objective from the first lens to the focus position is TTL, the back aperture of the chromatic dispersion microscope objective is WD, and the following relationships are satisfied:

[0050] 0.25≤WD / TTL≤0.30.

[0051] According to an embodiment of the present application, the refractive index of the first lens is n1, the refractive index of the second lens is n2, the refractive index of the third lens is n3, the refractive index of the fourth lens is n4, the refractive index of the fifth lens is n5, the refractive index of the sixth lens is n6, the refractive index of the seventh lens is n7, and the refractive index of the eighth lens is n8, and the following relationships are satisfied:

[0052] 1.70≤n1≤2.10;

[0053] 1.70≤n2≤2.00;

[0054] 1.40≤n3≤1.70;

[0055] 1.50≤n4≤1.90;

[0056] 1.60≤n5≤2.00;

[0057] 1.40≤n6≤1.80;

[0058] 1.80≤n7≤2.20;

[0059] 1.65≤n8≤2.00。

[0060] Compared with the prior art, the beneficial effects that can be achieved by the at least one technical solution adopted by the embodiments of the present application include: the dispersion microscope objective of the embodiments of the present application is a 5X objective, which is matched with a specially designed 2X tube lens to achieve a 10X magnification effect, and the object field of view is 8.8 mm, which is used in a high-precision D2W (chip and wafer) bonding vision system. In a high-precision wafer double-mark point bonding vision system, the specially designed large-field dispersion microscope objective of the embodiments of the present application can simultaneously observe the adjacent four mark points of the chip and the wafer that need to be bonded during the bonding process. Since the adjacent mark points are observed at the same time, the success rate of such wafer bonding is greatly improved. In addition, due to the characteristics of the dispersion microscope objective, only different wavelengths of light sources need to be replaced to adapt to different bonding requirements, so it can be widely used in high-precision wafer bonding equipment, and is conducive to popularizing high-precision wafer bonding technology. BRIEF DESCRIPTION OF DRAWINGS

[0061] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0062] Figure 1 is a structure diagram of a 5X large-field dispersion microscope objective of the embodiments of the present application with an object field of view of 8.8 mm;

[0063] Figure 2 is a point array diagram of the large-field dispersion microscope objective of the embodiments of the present application (wavelength 1.1 μm);

[0064] Figure 3 is a point array diagram of the large-field dispersion microscope objective of the embodiments of the present application (wavelength 1.2 μm);

[0065] Figure 4 is a point array diagram of the large-field dispersion microscope objective of the embodiments of the present application (wavelength 1.3 μm);

[0066] Figure 5 is the MTF curve (wavelength 1.1 μm) of the large field dispersion microscope objective of the embodiment of the present application;

[0067] Figure 6 is the MTF curve (wavelength 1.2 μm) of the large field dispersion microscope objective of the embodiment of the present application;

[0068] Figure 7 is the MTF curve (wavelength 1.3 μm) of the large field dispersion microscope objective of the embodiment of the present application;

[0069] Figure 8 is the distortion curve (wavelength 1.1 μm) of the large field dispersion microscope objective of the embodiment of the present application;

[0070] Figure 9 is the distortion curve (wavelength 1.2 μm) of the large field dispersion microscope objective of the embodiment of the present application;

[0071] Figure 10 is the distortion curve (wavelength 1.3 μm) of the large field dispersion microscope objective of the embodiment of the present application. DETAILED DESCRIPTION

[0072] The embodiments of the present application will be described in detail below with reference to the drawings.

[0073] The above embodiments are only some of the embodiments of the present application, but not all the embodiments of the present application. The present application can also be implemented or applied through other different specific embodiments, and the details in the specification can be modified or changed based on different views and applications without departing from the spirit of the present application. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0074] As shown in Figure 1 , the embodiment of the present application provides a large field dispersion microscope objective, which comprises, from the exit side to the object side, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7 and an eighth lens L8; wherein the first lens L1 and the second lens L2 are cemented into a set of double cemented lenses;

[0075] and the following relationship is satisfied: 0.001≤Δλ / ΔWD≤0.002;

[0076] 20nm≤Δλ;

[0077] 20μm≤ΔWD, WD(λ min )≥35mm;

[0078] 2y=8.8mm;

[0079] NA≥0.35;

[0080] wherein λ min is the shortest working wavelength of the dispersive microscope objective, λ max is the longest working wavelength of the dispersive microscope objective, Δλ=λ max -λ min ; WD(λ max ) is the back focal length corresponding to the longest working wavelength, WD(λ min ) is the back focal length corresponding to the shortest working wavelength, ΔWD=WD(λ max )-WD(λ min ), y is the half field of view, and NA is the numerical aperture of the dispersive microscope objective.

[0081] In a D2W (chip to wafer) bonding vision system, a conventional microscope objective needs to be achromatic or apochromatic designed, i.e. to design the focusing positions of all wavelengths together. The dispersive microscope objective of the embodiments of the present application adopts the opposite idea, the principle of which is to use the dispersion characteristics of the lens to design different wavelengths at different focusing positions, which is similar to the dispersive lens of spectral confocal, but is obviously different from the dispersive lens. The target of the dispersive lens is to measure the position, not to image, so the dispersive lens only considers the design of the on-axis point, and the numerical aperture (NA) is small, and a large range of dispersion distance is needed. The dispersive microscope objective used in the embodiments of the present application needs to image, so the field of view of the camera needs to be considered, i.e. the performance of each wavelength in a certain field of view needs to be considered. The distance between the bonded chip and wafer is close (tens of microns), and in order to prevent up-down imaging crosstalk, the depth of field range of each wavelength is small, which requires a certain numerical aperture.

[0082] Therefore, the dispersion microscope objective needs to have similar parameters of a microscope objective and has the characteristics of a dispersion lens. However, the field of view of a high-power microscope objective is very small, and since a small field of view infrared camera (sensor 1 / 2 inch, diagonal 8.2 mm) is used in the bonding vision system, the corresponding object field of view is only 0.82 mm for a 10X system. The maximum interval of the two marks of the chip and wafer that need to be bonded is several millimeters, so the dispersion microscope objective not only needs to have a high numerical aperture (a large numerical aperture corresponds to a small field of view) of a microscope objective, but also needs to have a large field of view. In addition, since the vision system needs to observe the marks from the bottom through the transparent chuck (stage), the thicker the thickness of the chuck stage, the better the flatness of the chuck stage, the more conducive to the bonding of the chip and wafer, so while meeting the large field of view and large NA, it also needs to ensure sufficient working distance.

[0083] In an embodiment, the shortest working wavelength λ min of the dispersion microscope objective is 1100 nm, and the longest working wavelength λ max of the dispersion microscope objective is 1300 nm; 100 μm≤ΔWD≤200 μm. In this embodiment, it is verified in the near-infrared transmission detection wafer that the wavelength of 1.1-1.3 μm has the best effect, so the design wavelength range of the large field of view dispersion microscope objective in this embodiment is 1.1-1.3 μm.

[0084] For different bonding processes, the positions of the chip and wafer are different, usually between 30-200 μm, so the dispersion objective is designed for 1.1-1.3 μm, and the focusing distance of 1.1 μm and 1.3 μm is different by 200 μm. The focusing distance of the wavelength in this wavelength range is basically linear, i.e. 1.1 μm and 1.2 μm are different by 100 μm, and so on. Therefore, for different bonding processes, only different wavelength light sources need to be replaced to obtain clear imaging of different distances of the chip and wafer, which can quickly adapt to different high-precision bonding requirements.

[0085] Therefore, in the high-precision wafer double-mark point bonding vision system, the large field of view dispersion microscope objective specially designed in the embodiment of the application can simultaneously observe the adjacent four mark points of the chip and wafer that need to be bonded in real time during the bonding process. Since the adjacent mark points are observed at the same time, the success rate of this type of wafer bonding is greatly improved. In addition, due to the characteristics of the dispersion microscope objective, only different wavelength light sources need to be replaced to adapt to different bonding requirements, so it can be widely used in high-precision wafer bonding equipment and is conducive to the popularization of high-precision wafer bonding technology.

[0086] In one embodiment, the first lens is a meniscus positive lens, the second lens is a biconcave negative lens, the third lens is a meniscus positive lens, the fourth lens is a biconvex positive lens, the fifth lens is a biconvex positive lens, the sixth lens is a meniscus positive lens, the seventh lens is a positive negative lens, and the eighth lens is a meniscus positive lens.

[0087] In one embodiment, the focal length of the dispersion microscope objective is f, the numerical aperture of the dispersion microscope objective is NA, and the following relationship is satisfied:

[0088] 12≤f*NA≤16.

[0089] In a specific implementation, the lens parameters of the dispersion microscope objective are as follows:

[0090] 1) f = 40 mm (focal length f is 40 mm, matching 400 mm tube lens, magnification is -10X, the objective of the present embodiment is a 5X objective);

[0091] 2) Numerical aperture NA: 0.35;

[0092] 3) Field of view: 8.8 mm (large field of view);

[0093] 4) Back working distance WD: ≥ 35 mm (large working distance);

[0094] 5) Wavelength: 1.1-1.3 μm;

[0095] 6) Difference between focusing positions of two extreme wavelengths: 200 μm (i.e., the focusing positions of 1.1 μm and 1.3 μm differ by 200 μm);

[0096] 7) Distortion: ≤ 0.7%;

[0097] 8) Infinite conjugate telecentric design;

[0098] 9) Thickness compensation design (30 mm fused quartz chuck table + 0.8 mm glass or Si substrate).

[0099] In one embodiment, the focal length of the first lens and the second lens glued into a set of double-glued lenses is f 12 , the focal length of the third lens is f3, the focal length of the fourth lens is f4, the focal length of the fifth lens is f5, the focal length of the sixth lens is f6, the focal length of the seventh lens is f7, the focal length of the eighth lens is f8, the focal length of the dispersion microscope objective is f, and the following relationship is satisfied:

[0100] -1.20≤f 12 / f≤-0.90;

[0101] 2.60≤f3 / f≤3.50;

[0102] 2.30≤f4 / f≤3.15;

[0103] 2.00≤f5 / f≤2.75;

[0104] 1.90≤f6 / f≤2.60;

[0105] -0.90≤f7 / f≤-0.65;

[0106] 1.40≤f8 / f≤1.85.

[0107] In one embodiment, the first surface of the first lens has a radius of curvature r1, the cemented surface of the second surface of the first lens and the first surface of the second lens has a radius of curvature r2, the second surface of the second lens has a radius of curvature r3, the first surface of the third lens has a radius of curvature r4, the second surface of the third lens has a radius of curvature r5, the first surface of the fourth lens has a radius of curvature r6, the second surface of the fourth lens has a radius of curvature r7, the first surface of the fifth lens has a radius of curvature r8, the second surface of the fifth lens has a radius of curvature r9, the first surface of the sixth lens has a radius of curvature r 10 , the second surface of the sixth lens has a radius of curvature r 11 , the first surface of the seventh lens has a radius of curvature r 12 , the second surface of the seventh lens has a radius of curvature r 13 , the first surface of the eighth lens has a radius of curvature r 14 , the second surface of the eighth lens has a radius of curvature r 15 , and the following relations are satisfied:

[0108] 3.15≤(r1+r2) / (r1-r2)≤4.25;

[0109] -1.30≤(r2+r3) / (r2-r3)≤-1.00;

[0110] 1.20≤(r4+r5) / (r4-r5)≤1.60;

[0111] 1.50≤(r6+r7) / (r6-r7)≤2.00;

[0112] -2.40≤(r8+r9) / (r8-r9)≤-1.80;

[0113] -2.20≤(r 10 +r 11 ) / (r 10 -r 11 )≤-1.60;

[0114] 1.10 ≤ (r 12 +r 13 ) / (r 12 -r 13 ) ≤ 1.50;

[0115] -2.00 ≤ (r 14 +r 15 ) / (r 14 -r 15 ) ≤ -1.50.

[0116] In a specific implementation, the range of the radius of curvature r is specifically: 34.0 ≤ r1≤ 42.0, 20.0 ≤ r2≤ 24.0, 314.0 ≤ r3≤ 383.5, 356.0 ≤ r4≤ 435.0, 54.5 ≤ r5≤ 66.5, 301.0 ≤ r6≤ 368.0, 87.0 ≤ r7≤ 106.5, 45.5 ≤ r8≤ 55.5, 127.0 ≤ r9≤ 155.0, 40.0 ≤ r 10 ≤ 44.0, 115.0 ≤ r 11 ≤ 140.5, 184.0 ≤ r 12 ≤ 225.0, 21.5 ≤ r 13 ≤ 26.0, 35.5 ≤ r 14 ≤ 43.5, 135.0 ≤ r 15 ≤ 165.0.

[0117] In one embodiment, the thickness of the first lens is d1, the thickness of the second lens is d2, the thickness of the third lens is d3, the thickness of the fourth lens is d4, the thickness of the fifth lens is d5, the thickness of the sixth lens is d6, the thickness of the seventh lens is d7, the thickness of the eighth lens is d8, the total length of the chromatic dispersion microscope objective from the first lens to the focus position is TTL, and the following relationships are satisfied:

[0118] 0.06 ≤ d1 / TTL ≤ 0.08;

[0119] 0.04 ≤ d2 / TTL ≤ 0.06;

[0120] 0.07 ≤ d3 / TTL ≤ 0.10;

[0121] 0.07 ≤ d4 / TTL ≤ 0.10;

[0122] 0.07 ≤ d5 / TTL ≤ 0.10;

[0123] 0.08 ≤ d6 / TTL ≤ 0.10;

[0124] 0.04 ≤ d7 / TTL ≤ 0.06;

[0125] 0.05 < d8 / TTL < 0.07.

[0126] In implementation, the thickness d is specifically in the range of 9.0 < d1 < 1.1, 4.5 < d2 < 5.5, 10.5 < d3 < 13.0, 10.5 < d4 < 13.0, 10.5 < d5 < 13.0, 11.5 < d6 < 14.0, 4.5 < d7 < 5.5, and 7.0 < d8 < 9.0. The total length TTL of the dispersion microscope objective from the first lens to the focus position is in the range of 120-150 mm.

[0127] In one embodiment, the interval between the double cemented lens formed by cementing the first lens and the second lens and the third lens is t1, the interval between the third lens and the fourth lens is t2, the interval between the fourth lens and the fifth lens is t3, the interval between the fifth lens and the sixth lens is t4, the interval between the sixth lens and the seventh lens is t5, the interval between the seventh lens and the eighth lens is t6, the total length of the dispersion microscope objective from the first lens to the focus position is TTL, and the following relationships are satisfied:

[0128] 0.07 < t1 / TTL < 0.10;

[0129] 0.01 < t2 / TTL < 0.02;

[0130] 0.005 < t3 / TTL < 0.01;

[0131] 0.04 < t4 / TTL < 0.06;

[0132] 0.01 < t5 / TTL < 0.02;

[0133] 0.03 < t6 / TTL < 0.04.

[0134] In one embodiment, the total length of the dispersion microscope objective from the first lens to the focus position is TTL, the back focal length of the dispersion microscope objective is WD, and the following relationship is satisfied:

[0135] 0.25 < WD / TTL < 0.30.

[0136] In one embodiment, the refractive index of the first lens is n1, the refractive index of the second lens is n2, the refractive index of the third lens is n3, the refractive index of the fourth lens is n4, the refractive index of the fifth lens is n5, the refractive index of the sixth lens is n6, the refractive index of the seventh lens is n7, and the refractive index of the eighth lens is n8, and the following relationships are satisfied:

[0137] 1.70≤n1≤2.10; 1.70≤n2≤2.00; 1.40≤n3≤1.70; 1.50≤n4≤1.90; 1.60≤n5≤2.00; 1.40≤n6≤1.80; 1.80≤n7≤2.20; 1.65≤n8≤2.00.

[0138] Table 1 shows the design data of the 5X, 8.8mm field of view, dispersion microscope objective of the embodiment of the present application.

[0139] Table 1 Design data of dispersion microscope objective (1)

[0140]

[0141] As shown in Figures 2-10 . Figure 2 is the spot diagram of the dispersion microscope objective of the embodiment of the present application (wavelength 1.1 μm); Figure 3 is the spot diagram of the dispersion microscope objective of the embodiment of the present application (wavelength 1.2 μm); Figure 4 is the spot diagram of the dispersion microscope objective of the embodiment of the present application (wavelength 1.3 μm); Figure 5 is the MTF curve of the dispersion microscope objective of the embodiment of the present application (wavelength 1.1 μm); Figure 6 is the MTF curve of the dispersion microscope objective of the embodiment of the present application (wavelength 1.2 μm); Figure 7 is the MTF curve of the dispersion microscope objective of the embodiment of the present application (wavelength 1.3 μm); Figures 5-7 In the figure, the horizontal axis spatial frequency in cycles per mm is the spatial frequency, with the unit of cycles per mm, and the vertical axis Modulus of the OTF is the optical transfer function value; Figure 8 is the distortion curve of the dispersion microscope objective of the embodiment of the present application (wavelength 1.1 μm); Figure 9 is the distortion curve of the dispersion microscope objective of the embodiment of the present application (wavelength 1.2 μm); Figure 10 is the distortion curve of the dispersion microscope objective of the embodiment of the present application (wavelength 1.3 μm).

[0142] It can be seen from Figures 2-4 that the spot diagrams of the dispersion microscope objective at three wavelengths are all within the Airy disk, from Figures 5-7 it can be seen that the MTF curves of the dispersion microscope objective at three wavelengths are close to the diffraction limit, and from Figures 8-10 it can be seen that the distortion values of the dispersion microscope objective at three wavelengths are less than 0.7%, which shows that the imaging quality of the dispersion objective in the range of 1.1-1.3 μm is close to the theoretical limit and the image is deformed extremely small in the large field of view.

[0143] The above merely provides the specific implementation of the present application, but the protection scope of the present application is not limited to this. Any changes or replacements within the technical scope disclosed by the present application can be easily conceived by the person skilled in the art, and should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A large field-of-view dispersive microscope objective, characterized in that, The dispersive microscope objective comprises, from the exit side to the object side, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and an eighth lens; wherein the first lens and the second lens are cemented together to form a cemented doublet lens. And it satisfies the following relationship: 0.001≤Δλ / ΔWD≤0.002; 20nm≤Δλ; 20μm≤ΔWD,WD(λ min )≥35mm; 2y = 8.8 mm; NA ≥ 0.35; Where, λ min λ is the shortest operating wavelength of the dispersive microscope objective. max Δλ = λ, where λ is the longest operating wavelength of the dispersive microscope objective. max -λ min WD(λ) max ) represents the back intercept corresponding to the longest operating wavelength, WD(λ) min ) represents the back intercept corresponding to the shortest operating wavelength, ΔWD = WD(λ) max )-WD(λ min ), where y is the half field of view and NA is the numerical aperture of the dispersive microscope objective.

2. The large field-of-view dispersive microscope objective according to claim 1, characterized in that, The shortest operating wavelength λ of the dispersive microscope objective min The longest operating wavelength λ of the dispersive microscope objective is 1100 nm. max The value is 1300nm; 100μm≤ΔWD≤200μm.

3. The large field-of-view dispersive microscope objective according to claim 1, characterized in that, The dispersive microscope objective has a focal length of f and a numerical aperture of NA, and satisfies the following relationship: 12≤f*NA≤16.

4. The large field-of-view dispersive microscope objective according to claim 3, characterized in that, The dispersive microscope objective has a focal length of f = 40 mm and a numerical aperture NA of 0.

35.

5. The large field-of-view dispersive microscope objective according to claim 1, characterized in that, The focal length of the cemented doublet formed by bonding the first lens and the second lens is f. 12 The focal length of the third lens is f3, the focal length of the fourth lens is f4, the focal length of the fifth lens is f5, the focal length of the sixth lens is f6, the focal length of the seventh lens is f7, the focal length of the eighth lens is f8, and the focal length of the dispersive microscope objective is f, and the following relationship is satisfied: -1.20≤f 12 / f≤-0.90; 2.60≤f³ / f≤3.50; 2.30≤f4 / f≤3.15; 2.00≤f5 / f≤2.75; 1.90≤f6 / f≤2.60; -0.90≤f7 / f≤-0.65; 1.40≤f8 / f≤1.

85.

6. The large field-of-view dispersive microscope objective according to claim 1, characterized in that, The radius of curvature of the first surface of the first lens is r1; the radius of curvature of the cemented surface formed by the second surface of the first lens and the first surface of the second lens is r2; the radius of curvature of the second surface of the second lens is r3; the radius of curvature of the first surface of the third lens is r4; the radius of curvature of the second surface of the third lens is r5; the radius of curvature of the first surface of the fourth lens is r6; the radius of curvature of the second surface of the fourth lens is r7; the radius of curvature of the first surface of the fifth lens is r8; the radius of curvature of the second surface of the fifth lens is r9; and the radius of curvature of the first surface of the sixth lens is r... 10 The radius of curvature of the second surface of the sixth lens is r. 11 The radius of curvature of the first surface of the seventh lens is r. 12 The radius of curvature of the second surface of the seventh lens is r. 13 The radius of curvature of the first surface of the eighth lens is r. 14 The radius of curvature of the second surface of the eighth lens is r. 15 And satisfy the following relationship: 3.15≤(r1+r2) / (r1-r2)≤4.25； -1.30≤(r2+r3) / (r2-r3)≤-1.00； 1.20≤(r4+r5) / (r4-r5)≤1.60； 1.50≤(r6+r7) / (r6-r7)≤2.00； -2.40≤(r8+r9) / (r8-r9)≤-1.80； -2.20≤(r 10 +r 11 ) / (r 10 -r 11 )≤-1.60； 1.10≤(r 12 +r 13 ) / (r 12 -r 13 )≤1.50； -2.00≤(r 14 +r 15 ) / (r 14 -r 15 )≤-1.50。 7. The large field-of-view dispersive microscope objective according to claim 1, characterized in that, The thickness of the first lens is d1, the thickness of the second lens is d2, the thickness of the third lens is d3, the thickness of the fourth lens is d4, the thickness of the fifth lens is d5, the thickness of the sixth lens is d6, the thickness of the seventh lens is d7, and the thickness of the eighth lens is d8. The total length of the dispersive microscope objective from the first lens to the focusing position is TTL, and it satisfies the following relationship: 0.06≤d1 / TTL≤0.08; 0.04≤d2 / TTL≤0.06; 0.07≤d3 / TTL≤0.10; 0.07≤d4 / TTL≤0.10; 0.07≤d5 / TTL≤0.10; 0.08≤d6 / TTL≤0.10; 0.04≤d7 / TTL≤0.06; 0.05≤d8 / TTL≤0.

07.

8. The large field-of-view dispersive microscope objective according to claim 1, characterized in that, The distance between the cemented doublet lens formed by the first and second lenses and the third lens is t1; the distance between the third lens and the fourth lens is t2; the distance between the fourth lens and the fifth lens is t3; the distance between the fifth lens and the sixth lens is t4; the distance between the sixth lens and the seventh lens is t5; the distance between the seventh lens and the eighth lens is t6; and the total length of the dispersive microscope objective from the first lens to the focusing position is TTL, and satisfies the following relationship: 0.07≤t1 / TTL≤0.10; 0.01≤t2 / TTL≤0.02; 0.005≤t3 / TTL≤0.01; 0.04≤t4 / TTL≤0.06; 0.01≤t5 / TTL≤0.02; 0.03≤t6 / TTL≤0.

04.

9. The large field-of-view dispersive microscope objective according to claim 1, characterized in that, The total length of the dispersive microscope objective from the first lens to the focusing position is TTL, and the back intercept of the dispersive microscope objective is WD, and satisfies the following relationship: 0.25≤WD / TTL≤0.

30.

10. The large field-of-view dispersive microscope objective according to claim 1, characterized in that, The first lens has a refractive index of n1, the second lens has a refractive index of n2, the third lens has a refractive index of n3, the fourth lens has a refractive index of n4, the fifth lens has a refractive index of n5, the sixth lens has a refractive index of n6, the seventh lens has a refractive index of n7, and the eighth lens has a refractive index of n8, and satisfies the following relationship: 1.70≤n1≤2.10； 1.70≤n2≤2.00； 1.40≤n3≤1.70； 1.50≤n4≤1.90； 1.60≤n5≤2.00； 1.40≤n6≤1.80； 1.80≤n7≤2.20； 1.65≤n8≤2.00。

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