Microscope tube lens

Abstract

The utility model belongs to the technical field of microscopes, and particularly discloses a microscope tube lens, which comprises a first lens, a second lens, a third lens, a fourth lens and a fifth lens which are sequentially arranged from a tube lens entrance pupil to an image plane, the first lens is connected with the second lens, the third lens is an independent lens, and the fourth lens is connected with the fifth lens; the first lens is a biconvex lens, the second lens is a biconcave lens, the third lens is a biconvex lens, the fourth lens is a biconvex lens, and the fifth lens is a biconcave lens. The lens barrel and lens light path structure of the infinite microscope has a larger field of view and a larger entrance pupil diameter, and diffraction spots of the lens barrel and lens light path structure are obviously smaller than Airy spots.

Description

TECHNICAL FIELD

[0001] The utility model relates to microscope technical field, concretely relates to a microscope tube lens. BACKGROUND

[0002] In the field of life science and industrial detection, microscopic observation is an indispensable technology. However, these detection requirements often need to detect a sample in a large range and high resolution. A common practice is to use a high NA, small field of view objective lens to collect the sample surface multiple times, and then use related technologies to splice the images of each sub-field of view to realize high-resolution super-large field image acquisition. The splicing system is relatively simple, but since each sub-field of view is relatively small, it will consume more time and effort.

[0003] The existing Chinese patent with publication number CN118818717A discloses a large-field, small-aberration tube lens optical path structure for an infinity-corrected microscope, which is arranged in order from an infinity objective lens to an image plane and includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens. The first lens is a concave-to-object-side crescent lens; the second lens is a double-concave lens; the third lens is a double-convex lens; the second lens and the third lens are cemented together; the fourth lens is a convex-to-object-side crescent lens; the fifth lens is a double-convex lens; the sixth lens is a concave-to-object-side crescent lens; and the fourth lens, the fifth lens, and the sixth lens are cemented together.

[0004] The field of view range, entrance pupil diameter, and diffraction spot size of the optical path structure in the above-mentioned prior art are close to the size of an Airy disk, and there is room for improvement. INVENTION CONTENTS

[0005] The utility model provides a kind of microscope tube lens, it is to a kind of infinity microscope barrel lens optical path structure with greater field of view, greater entrance pupil diameter, diffraction spot is significantly smaller than Airy disk.

[0006] The utility model discloses a kind of microscope tube lens, including the first lens, the second lens, the third lens, the fourth lens, the fifth lens that are arranged in order from tube lens entrance pupil to image plane;

[0007] The first lens is connected with the second lens, the third lens is a separate lens, the fourth lens and the fifth lens are connected;

[0008] The first lens is a double-convex lens, the second lens is a double-concave lens, the third lens is a double-convex lens, the fourth lens is a double-convex lens, and the fifth lens is a double-concave lens.

[0009] Further, the first lens and the second lens are cemented together, and the fourth lens and the fifth lens are also cemented together.

[0010] Further, the ratio of the focal length f1 of the first lens to the optical path focal length f, the material refractive index Nd1 and the Abbe number Vd1 are as follows respectively:

[0011] 0.4 < f1 / f < 0.8; 1.55 < Nd1 < 1.72; 53 < Vd1 < 59.

[0012] Further, the ratio of the focal length f2 of the second lens to the optical path focal length f, the material refractive index Nd2 and the Abbe number Vd2 are as follows respectively:

[0013] -20 < f2 / f < -7; 1.68 < Nd2 < 1.79; 28 < Vd2 < 45.

[0014] Further, the ratio of the focal length f3 of the third lens to the optical path focal length f, the material refractive index Nd3 and the Abbe number Vd3 are as follows respectively:

[0015] 0.45 < f3 / f < 0.75; 1.53 < Nd3 < 1.64; 55 < Vd3 < 68.

[0016] Further, the ratio of the focal length f4 of the fourth lens to the optical path focal length f, the material refractive index Nd4 and the Abbe number Vd4 are as follows respectively:

[0017] 0.6 < f4 / f < 1.2; 1.55 < Nd4 < 1.68; 38 < Vd4 < 51.

[0018] Further, the ratio of the focal length f5 of the fifth lens to the optical path focal length f, the material refractive index Nd5 and the Abbe number Vd5 are as follows respectively:

[0019] -0.35 < f5 / f < -0.48; 1.57 < Nd5 < 1.68; 38 < Vd5 < 51.

[0020] Further, the diameter of the entrance pupil of the tube lens is 16mm < D < 20mm.

[0021] Further, the image field of the optical system of the microscope tube lens is 12mm ≤ Y ≤ 16mm.

[0022] Further, the optical path focal length of the optical system of the microscope tube lens is 100mm ≤ f ≤ 120mm.

[0023] Compared with the prior art, the utility model has the advantages and beneficial effects that:

[0024] 1、The shape design of the first lens, the second lens, the third lens, the fourth lens and the fifth lens in the utility model can make the optical system obtain smaller focal length under the condition of using less lens.

[0025] 2、The utility model discloses a pupil diameter size is 16mm < D < 20mm, can adapt to more big pupil diameter microscope objective lens;

[0026] 3、The utility model discloses a greater image side field of view and shorter focal length, according to the formula of the size of object side field of view y=Y / (f / f 物镜 ), wherein y is: object side field of view, Y is: image side field of view, f is: optical path focal length, f 物镜 Is: objective lens focal length, and objective lens focal length f 物镜 Is unchangeable, so the object side field of view becomes larger;

[0027] 4、The utility model discloses the lens shape and the combination between the lens can make the optical system diffraction spot size less than airy disk size, so the utility model has more excellent imaging quality. BRIEF DESCRIPTION OF DRAWINGS

[0028] The drawings explained here are used to provide further understanding of the embodiments of the utility model, constitute a part of this application, and do not constitute the limitation to the embodiments of the utility model. In the drawings:

[0029] Fig. 1 It is the tube lens optical path structure schematic diagram in the utility model discloses a kind of microscope tube lens embodiment;

[0030] Fig. 2 It is the point column diagram of the tube lens in the utility model discloses a kind of microscope tube lens embodiment.

[0031] Mark and corresponding component name in the drawing:

[0032] Pupil 5, first lens 6, second lens 7, third lens 8, fourth lens 9, fifth lens 10, image plane 11. DETAILED DESCRIPTION

[0033] To make the purpose, technical scheme and advantage of the utility model more clear and obvious, the utility model is further explained in detail below with examples and drawings, and the illustrative embodiment of the utility model and its explanation are only used to explain the utility model, and not as the limitation to the utility model.

[0034] In the description of this invention, it should be noted that the terms "first," "second," "third," etc., are used only for distinguishing descriptions and should not be construed as indicating or implying relative importance. In the description of this document, the terms "installed," "set," "equipped with," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral structure; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, components, or constituent parts. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0035] Example 1

[0036] like Figs. 1-2 As shown, this embodiment 1 provides a microscope tube, including a first lens 6, a second lens 7, a third lens 8, a fourth lens 9, and a fifth lens 10 arranged sequentially from the entrance pupil 5 to the image plane 11; the first lens 6 is connected to the second lens 7, the third lens 8 is a separate lens, and the fourth lens 9 and the fifth lens 10 are connected. In this embodiment, the first lens 6 and the second lens 7, as well as the fourth lens 9 and the fifth lens 10, are all cemented together.

[0037] In this embodiment, the first lens 6 is a biconvex lens, the second lens 7 is a biconcave lens, the third lens 8 is a biconvex lens, the fourth lens 9 is a biconvex lens, and the fifth lens 10 is a biconcave lens.

[0038] The ratio of the focal length f1 to the optical path focal length f, the refractive index Nd1 of the material, and the Abelian coefficient Vd1 of the first lens 6 are as follows:

[0039] 0.4 <f1 / f<0.8;1.55<Nd1<1.72;53<Vd1<59;

[0040] The ratio of the focal length f2 to the optical path focal length f of the second lens 7, the refractive index Nd2 of the material, and the Abelian coefficient Vd2 are as follows:

[0041] -20 <f2 / f<-7;1.68<Nd2<1.79;28<d2<45;

[0042] The ratio of the focal length f3 to the optical path focal length f, the refractive index Nd3, and the Abelian coefficient Vd3 of the third lens 8 are as follows:

[0043] 0.45 <f3 / f<0.75;1.53<Nd3<1.64;55<Vd3<68;

[0044] The ratio of the focal length f4 of the fourth lens 9 to the optical path focal length f, the material refractive index Nd4 and the Abbe number Vd4 are as follows respectively:

[0045] 0.6 < f4 / f < 1.2; 1.55 < Nd4 < 1.68; 38 < Vd4 < 51;

[0046] The ratio of the focal length f5 of the fifth lens 10 to the optical path focal length f, the material refractive index Nd5 and the Abbe number Vd5 are as follows respectively:

[0047] -0.35 < f5 / f < -0.48; 1.57 < Nd5 < 1.68; 38 < Vd5 < 51.

[0048] The specific parameters of the lens are shown in Table 1:

[0049] Table 1

[0050]

[0051] Wherein the lens surface numbered S1, S2 is the first lens 6, the lens surface numbered S2, S3 is the second lens 7, the lens surface numbered S4, S5 is the third lens 8, the lens surface numbered S6, S7 is the fourth lens 9, and the lens surface numbered S7, S8 is the fifth lens 10.

[0052] In the embodiment, the diameter (D) of the entrance pupil 5 of the tube lens is 16mm < D < 20mm, which can adapt to more microscopes with large exit pupil diameters. Specifically, the diameter of the entrance pupil 5 in the embodiment is preferably 17mm. According to the background art patent

[0111] paragraph, the focal length f of the tube lens is 124mm, and the aperture value FNo = 8.6. According to the calculation method: entrance pupil diameter = f / FNo, the entrance pupil diameter of the tube lens in the background art patent is 14.4mm. It can be seen that the entrance pupil 5 in the embodiment can adapt to more microscopes with large exit pupil diameters, and is more versatile.

[0053] In the embodiment, the image field of the optical system of the microscope tube lens is 12mm ≤ Y ≤ 16mm, and the optical path focal length of the optical system of the microscope tube lens is 100mm ≤ f ≤ 120mm. The diffraction spot of the optical system of the microscope tube lens in the embodiment is smaller than the Airy disk.

[0054] The microscope tube lens in the embodiment has a larger image field and a shorter focal length. According to the calculation formula y = Y / (f / f 物镜 ), wherein y is the object field; Y is the image field; f is the optical path focal length (also referred to as the tube lens focal length); f 物镜 is the objective lens focal length. Since the objective lens focal length f 物镜 is constant, the object field becomes larger.

[0055] When using the same magnification of the microscope objective, the microscope tube lens of the utility model can obtain a larger object field (for example, the object field of the 10x objective lens is 3.2mm, while the object field of the prior art is 1.79mm).

[0056] In combination Fig. 2 As shown in the utility model, the structure design and combination of the first lens 6, the second lens 7, the third lens 8, the fourth lens 9 and the fifth lens 10 make the diffraction spot diameter of the optical system smaller than the Airy spot diameter, the imaging effect reaches the diffraction limit, and the microscope tube lens has better imaging quality. In the prior art, only the spot diameter of the central field is smaller than the Airy spot diameter, and the spot diameter of the non-central field is larger than the Airy spot diameter, so the imaging effect does not reach the diffraction limit.

[0057] In the embodiment, the optical path structure composed of the first lens 6, the second lens 7, the third lens 8, the fourth lens 9 and the fifth lens 10 is sequentially arranged from the tube lens entrance pupil 5 to the image plane 11, and the first lens 6, the second lens 7, the third lens 8, the fourth lens 9 and the fifth lens 10 make the incident parallel light beam pass through the first lens 6, the second lens 7, the third lens 8, the fourth lens 9 and the fifth lens 10 in sequence to form an outgoing light beam.

[0058] When the staff assembles the tube lens, the cemented lenses of the first lens 6 and the second lens 7, the third lens 8, the fourth lens 9 and the fifth lens 10 are sequentially installed from the tube lens entrance pupil 5 to the image plane 11.

[0059] When imaging, the incident parallel light beam passes through the first lens 6, the second lens 7, the third lens 8, the fourth lens 9 and the fifth lens 10 in sequence to form an outgoing light beam. In the embodiment, the incident parallel light beam is the light beam emitted from the objective lens exit pupil, and the outgoing light beam obtained by the five lenses is clearly imaged on the image plane 11.

[0060] The embodiment provides an infinite microscope tube lens with a larger field of view, a larger entrance pupil diameter and a diffraction spot smaller than the Airy spot, so that the imaging quality is better, and the economic and applicable value is high.

[0061] It is to be understood that the embodiments that have been described are merely illustrative of the principles of the application. Numerous modifications can be made to the application without departing from the scope of the application. Accordingly, the application is not to be limited to the embodiments described herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A microscope scope, characterized in that, The first lens, the second lens, the third lens, the fourth lens and the fifth lens are arranged in sequence from the entrance pupil of the tube lens to the image plane; The first lens is connected with the second lens, the third lens is a single lens, and the fourth lens and the fifth lens are connected; The first lens is a double convex lens, the second lens is a double concave lens, the third lens is a double convex lens, the fourth lens is a double convex lens, and the fifth lens is a double concave lens.

2. A microscope tube according to claim 1, characterized in that The first lens and the second lens are connected by cementing, and the fourth lens and the fifth lens are connected by cementing.

3. A microscope tube according to claim 1, wherein, The ratio of the focal length f1 of the first lens to the optical path focal length f, the material refractive index Nd1 and the Abbe number Vd1 are as follows: 0.4 < f1 / f < 0.8; 1.55 < Nd1 < 1.72; 53 < Vd1 < 59.

4. The microscope tube lens of claim 1, wherein, The ratio of the focal length f2 of the second lens to the optical path focal length f, the material refractive index Nd2 and the Abbe number Vd2 are as follows: -20 < f2 / f < -7; 1.68 < Nd2 < 1.79; 28 < d2 < 45.

5. The microscope tube of claim 1, wherein, The ratio of the focal length f3 of the third lens to the optical path focal length f, the material refractive index Nd3 and the Abbe number Vd3 are as follows: 0.45 < f3 / f < 0.75; 1.53 < Nd3 < 1.64; 55 < Vd3 < 68.

6. A microscope tube according to claim 1, characterized in that The ratio of the focal length f4 of the fourth lens to the optical path focal length f, the material refractive index Nd4 and the Abbe number Vd4 are as follows: 0.6 < f4 / f < 1.2; 1.55 < Nd4 < 1.68; 38 < Vd4 < 51.

7. The microscope tube of claim 1, wherein, The ratio of the focal length f5 of the fifth lens to the optical path focal length f, the material refractive index Nd5 and the Abbe number Vd5 are as follows: -0.35 < f5 / f < -0.48; 1.57 < Nd5 < 1.68; 38 < Vd5 < 51.

8. The microscope tube of claim 1, wherein, The diameter of the entrance pupil of the tube lens is 16mm < D < 20mm.

9. The microscope tube according to claim 1, characterized in that The image field of the optical system of the microscope tube lens is 12mm ≤ Y ≤ 16mm.

10. The microscope tube according to claim 1, characterized in that The optical path focal length of the optical system of the microscope tube lens is 100mm ≤ f ≤ 120mm.

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