Microscopic imaging system, microscopic imaging module and microscopic imaging device

Abstract

The present application relates to a kind of microscopic imaging systems, microscopic imaging module and microscopic imaging equipment.The microscopic imaging system includes first lens, second lens, third lens, fourth lens and fifth lens sequentially arranged from object side to image side along optical axis.The first lens has positive refractive power, the second lens has positive refractive power, the third lens has negative refractive power, the fourth lens has positive refractive power, and the fifth lens has positive refractive power;And the microscopic imaging system satisfies the following conditional expression: 10.50 < TTL / ImgH < 18.50.The above-mentioned microscopic imaging system is beneficial to the structure characteristics of the microscopic imaging system with miniaturization, compactness, can have higher imaging quality, show more details of object side to ensure the size range of imaging surface, so as to easily match higher pixel photosensitive element, obtain higher imaging quality, give consideration to the characteristics of miniaturization design and imaging effect is better, compared with traditional microscope lens, make structure more compact.

Description

Technical Field

[0001] The present invention relates to the field of optical microscopic imaging technology, and in particular to a microscopic imaging system, a microscopic imaging module and a microscopic imaging device. Background Art

[0002] With the continuous in-depth research in the optoelectronic information industry and the continuous advancement and development of microscopic imaging, the application of microscopic imaging modules is becoming increasingly widespread. In the process of biomaterial research, when observing tiny structures such as cells and material structures, the demand for optical microscopic imaging quality continues to increase due to the need for increasingly clear images. This has led to the gradual increase in the size of microscope lenses and the increase in conjugate distance. However, traditional microscope lenses typically have a long conjugate distance, making them unsuitable for compact installation. When installed on a PCB, they occupy a large amount of board space, affecting the layout of other components on the PCB. Summary of the Invention

[0003] Based on this, it is necessary to provide a microscopic imaging module, a microscopic imaging module and a microscopic imaging device to address the problem that the conjugate distance of the traditional microscope lens is too long.

[0004] A microscopic imaging system comprises a first lens, a second lens, a third lens, a fourth lens and a fifth lens arranged in sequence from the object side to the image side along an optical axis;

[0005] The first lens has positive refractive power, the second lens has positive refractive power, the third lens has negative refractive power, the fourth lens has positive refractive power, and the fifth lens has positive refractive power;

[0006] And the microscopic imaging system satisfies the following conditional formula:

[0007] 10.50<TTL / ImgH<18.50;

[0008] Wherein, TTL is the distance from the object side of the first lens to the imaging surface of the microscopic imaging system on the optical axis, and ImgH is half of the diagonal length of the effective pixel area of ​​the microscopic imaging system on the imaging surface.

[0009] In one embodiment, the microscopic imaging system satisfies the following conditional formula:

[0010] CRA<1.5°;

[0011] Wherein, CRA is the chief ray incident angle of the microscopic imaging system at the maximum field of view; and / or,

[0012] 0.14<NA<0.16;

[0013] Wherein, NA is the numerical aperture of the microscopic imaging system.

[0014] In one embodiment, the microscopic imaging system satisfies the following conditional formula:

[0015] 4.80<f1 / f2<19.10;

[0016] Wherein, f1 is the effective focal length of the first lens, and f2 is the effective focal length of the second lens. In one embodiment, the microscopic imaging system satisfies the following conditional formula:

[0017] 2.50<TTL / f<3.30;

[0018] Wherein, TTL is the distance from the object side surface of the first lens to the imaging surface of the microscopic imaging system on the optical axis, and f is the total effective focal length of the microscopic imaging system.

[0019] In one embodiment, the microscopic imaging system satisfies the following conditional formula:

[0020] 1.5<ImgH / ObjH<1.7;

[0021] Wherein, ObjH is half of the object height corresponding to the maximum field angle of the microscopic imaging system.

[0022] In one embodiment, the ratio of the refractive index to the Abbe number of the first lens, the ratio of the refractive index to the Abbe number of the second lens, the ratio of the refractive index to the Abbe number of the third lens, the ratio of the refractive index to the Abbe number of the fourth lens, and the ratio of the refractive index to the Abbe number of the fifth lens are 1.55 / 45.8, 1.62 / 60.3, 1.81 / 25.4, 1.62 / 60.3, and 1.68 / 55.2, respectively, with an allowable tolerance of 10%, an upper deviation of +5%, and a lower deviation of -5%.

[0023] In one embodiment, the microscopic imaging system further comprises an aperture, wherein the aperture is coaxially arranged between the object side and the first lens; and / or,

[0024] The aperture is coaxially arranged between the first lens and the second lens; and / or,

[0025] The aperture is coaxially arranged between the second lens and the third lens.

[0026] In one embodiment, the object side surface of the first lens is concave at the paraxial position, and the image side surface is convex at the paraxial position;

[0027] The object side surface of the second lens is convex at the paraxial position, and the image side surface is convex at the paraxial position;

[0028] The object side surface of the third lens is concave at the paraxial position, and the image side surface is concave at the paraxial position;

[0029] The object side surface of the fourth lens is concave at the paraxial position, and the image side surface is convex at the paraxial position;

[0030] The object-side surface of the fifth lens is convex at the paraxial position, and the image-side surface is convex at the paraxial position.

[0031] The above-mentioned microscopic imaging system, by setting the refractive powers of the first to fifth lenses arranged in sequence along the optical axis to "positive, positive, negative, positive, positive," respectively, helps shorten the overall length of the system and make the system structure more compact. At the same time, by rationally configuring the TTL / ImgH value to meet the conditional expression 10.50 < TTL / ImgH < 18.50, the microscopic imaging system is conducive to having miniaturized and compact structural characteristics, capable of achieving higher imaging quality, displaying more details on the object side, and ensuring the size range of the imaging surface, thereby facilitating the matching of higher-pixel photosensitive elements, achieving higher imaging quality, and taking into account the characteristics of miniaturized design and excellent imaging effects, making the structure more compact compared to traditional microscope lenses.

[0032] A microscopic imaging module includes a photosensitive element and the microscopic imaging system described in any of the above embodiments, wherein the photosensitive element is disposed on the image side of the microscopic imaging system. Employing the above microscopic imaging system in the microscopic imaging module, due to its short overall length, excellent imaging effect, and compact structure, enables a compact design of the microscopic imaging module while ensuring excellent imaging quality.

[0033] A microscopic imaging device comprises a housing and the above-mentioned microscopic imaging module, wherein the microscopic imaging module is disposed within the housing. Using the above-mentioned microscopic imaging module in the microscopic imaging device facilitates a compact design of the microscopic imaging device and ensures better imaging quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 Schematic diagram of the structure of the microscopic imaging system in the first embodiment of the present application;

[0035] Figure 2 is a spherical aberration curve diagram of the microscopic imaging system in the first embodiment of the present application;

[0036] Figure 3 Graphs showing aberration curves and distortion curves of the microscopic imaging system in the first embodiment of the present application;

[0037] Figure 4 : is a geometric aberration diagram of the microscopic imaging system in the first embodiment of the present application;

[0038] Figure 5 is a modulation function diagram of the microscopic imaging system in the first embodiment of the present application;

[0039] Figure 6 Schematic diagram of the structure of the microscopic imaging system in the second embodiment of the present application;

[0040] Figure 7 is a spherical aberration curve diagram of the microscopic imaging system in the second embodiment of the present application;

[0041] Figure 8 Graphs showing aberration curves and distortion curves of the microscopic imaging system in the second embodiment of the present application;

[0042] Figure 9 is a geometric aberration diagram of the microscopic imaging system in the second embodiment of the present application;

[0043] Figure 10 is a modulation function diagram of the microscopic imaging system in the second embodiment of the present application;

[0044] Figure 11 Schematic diagram of the structure of the microscopic imaging system in the third embodiment of the present application;

[0045] Figure 12 is a spherical aberration curve diagram of the microscopic imaging system in the third embodiment of the present application;

[0046] Figure 13 Graphs showing aberration curves and distortion curves of the microscopic imaging system in the third embodiment of the present application;

[0047] Figure 14 is a geometric aberration diagram of the microscopic imaging system in the third embodiment of the present application;

[0048] Figure 15 is a modulation function diagram of the microscopic imaging system in the third embodiment of the present application;

[0049] Figure 16 Schematic diagram of the structure of a microscopic imaging module in one embodiment of the present application.

[0050] In the picture:

[0051] 100, microscopic imaging system; 110, optical axis; L1, first lens; L2, second lens; L3, third lens; L4, fourth lens; L5, fifth lens; ST, aperture; 200, microscopic imaging module; 210, photosensitive element. DETAILED DESCRIPTION

[0052] To make the above-mentioned objects, features, and advantages of the present invention more readily apparent, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings. The following description sets forth numerous specific details to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways than those described herein, and those skilled in the art may make similar modifications without departing from the scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0053] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships 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, rather than indicating or implying 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 limiting the present invention.

[0054] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0055] In the present invention, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection; direct connection, or indirect connection through an intermediate medium; internal communication between two components, or interaction between two components, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0056] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0057] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only implementation methods.

[0058] Please refer to Figure 1 In some embodiments of the present application, the microscopic imaging system 100 includes, in order from the object side to the image side along the optical axis 110, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, and a fifth lens L5. Specifically, the first lens L1 includes an object-side surface S1 and an image-side surface S2, the second lens L2 includes an object-side surface S3 and an image-side surface S4, the third lens L3 includes an object-side surface S5 and an image-side surface S6, the fourth lens L4 includes an object-side surface S7 and an image-side surface S8, and the fifth lens L5 includes an object-side surface S9 and an image-side surface S10.

[0059] Among them, the first lens element L1 has positive refractive power, the second lens element L2 has positive refractive power, the third lens element L3 has negative refractive power, the fourth lens element L4 has positive refractive power, and the fifth lens element L5 has positive refractive power. Specifically, the object-side surface S1 of the first lens element L1 is concave at the paraxial direction, and the image-side surface S2 is convex at the paraxial direction; the object-side surface S3 of the second lens element L2 is convex at the paraxial direction, and the image-side surface S4 is convex at the paraxial direction; the object-side surface S5 of the third lens element L3 is concave at the paraxial direction, and the image-side surface S6 is concave at the paraxial direction; the object-side surface S7 of the fourth lens element L4 is concave at the paraxial direction, and the image-side surface S8 is convex at the paraxial direction; the object-side surface S9 of the fifth lens element L5 is convex at the paraxial direction, and the image-side surface S10 is convex at the paraxial direction. By setting the refractive powers of the first lens L1 to the fifth lens L5 arranged in sequence along the optical axis 110 to “positive, positive, negative, positive, positive” respectively, the microscopic imaging system 100 is more conducive to achieving a shorter overall system length.

[0060] In some embodiments, both the object-side and image-side surfaces of each lens of the microscopic imaging system 100 are spherical. Using a spherical structure can reduce processing difficulty, facilitate detection, and improve processing efficiency. In other embodiments, both the object-side and image-side surfaces of each lens of the microscopic imaging system 100 can be aspherical. It should be noted that the above embodiments are merely examples of some embodiments of the present application. In some embodiments, the surfaces of each lens in the microscopic imaging system 100 can be any combination of spherical and aspherical surfaces.

[0061] In some embodiments, the materials of the lenses in the microscopic imaging system 100 can all be glass or all be plastic. By using lenses made of plastic, the weight of the lenses in the microscopic imaging system 100 can be lighter, and the manufacturing cost of the microscopic imaging system 100 can be reduced. By using lenses made of glass, the heat resistance of the microscopic imaging system 100 can be increased, and the microscopic imaging system 100 can be suitable for more stringent environmental requirements. It should be noted that the materials of the lenses in the microscopic imaging system 100 can also be any combination of glass and plastic, and do not necessarily have to be all glass or all plastic.

[0062] Further, in some embodiments, the microscopic imaging system 100 satisfies the condition: 4.80 < f1 / f2 < 19.10. Wherein, f1 is the effective focal length of the first lens L1, and f2 is the effective focal length of the second lens L2. Specifically, f1 / f2 can be: 4.82, 4.83, 5.34, 5.35, 5.36, 19.04, or 19.05, etc. When the above condition is satisfied, the focal lengths of the first lens L1 and the second lens L2 can be reasonably configured, which helps to correct the imaging aberrations such as distortion and astigmatism of the microscopic imaging system 100, thereby improving the imaging quality of the system. When the value of f1 / f2 exceeds the upper limit of the above condition, a large field curvature will be caused, and when the value of f1 / f2 is lower than the lower limit of the above condition, the astigmatism will increase, which will affect the imaging quality of the microscopic imaging system 100.

[0063] In some embodiments, the microscopic imaging system 100 satisfies the condition: CRA < 1.5°. Wherein, CRA is the chief ray angle of incidence of the microscopic imaging system 100. Specifically, CRA can be: 1.40, 1.42, 1.44, 1.46, 1.48, or 1.49, etc. When the above relationship is satisfied, the angle of incidence of the chief ray on the imaging surface can be reduced, which can match a more stringent photosensitive element, and is conducive to the assembly of the microscopic imaging system 100 and the photosensitive element, thereby improving the overall imaging quality of the microscopic imaging system 100. When the value of CRA exceeds the upper limit of the above condition, the imaging quality will be reduced and other problems will be caused.

[0064] Further, the microscopic imaging system 100 satisfies the condition: 0.14 < NA < 0.16. Wherein, NA is the numerical aperture of the microscopic imaging system 100. The numerical aperture is used to measure the range of angles of light that the microscopic imaging system 100 can collect. Specifically, NA can be: 0.148, 0.149, 0.150, 0.151, or 0.152, etc. When the above relationship is satisfied, it is conducive to improving the luminous flux of the microscopic imaging system 100 and ensuring the imaging quality.

[0065] In some embodiments, the microscopic imaging system 100 satisfies the following condition: 10.50 < TTL / ImgH < 18.50. TTL is the distance from the object-side surface of the first lens L1 to the imaging plane of the microscopic imaging system 100 on the optical axis 110, i.e., the total optical length of the microscopic imaging system 100, and ImgH is half the diagonal length of the effective pixel area on the imaging plane of the microscopic imaging system 100. Specifically, TTL / ImgH can be 10.80, 10.81, 15.25, 15.26, 18.36, or 18.37, etc. By controlling the ratio of the total optical length of the microscopic imaging system 100 to half the image height corresponding to the maximum field of view angle of the microscopic imaging lens, the microscopic imaging system 100 can be miniaturized and compact in structure, with higher imaging quality, showing more details on the object side while ensuring the size range of the imaging surface, thereby facilitating matching with a higher-pixel photosensitive element and obtaining higher imaging quality. This balances miniaturization design with better imaging effects, making the structure more compact compared to traditional microscope lenses.

[0066] In one embodiment, the microscopic imaging system 100 satisfies the following conditional equation: 2.50 < TTL / f < 3.30. TTL is the distance from the object-side surface of the first lens L1 to the imaging plane of the microscopic imaging system 100 on the optical axis 110, and f is the total effective focal length of the microscopic imaging system 100. Specifically, TTL / f can be 2.70, 2.71, 3.12, 3.13, 3.21, or 3.22. Meeting this conditional equation helps shorten the overall length of the microscopic imaging system 100, achieving a miniaturized and compact design.

[0067] In one embodiment, the microscopic imaging system 100 satisfies the following conditional formula: 1.5<ImgH / ObjH<1.7. Wherein, ObjH is half of the object height corresponding to the maximum field of view angle of the microscopic imaging system 100. Specifically, ImgH / ObjH can be: 1.58, 1.59, 1.60, 1.61 or 1.62, etc. In the above relationship, the ratio of ImgH to ObjH is the magnification. By limiting the magnification between 1.5 and 1.7, it is possible to ensure that the magnification of the microscopic imaging system 100 meets the design parameter requirements while ensuring the compact and miniaturized design of the microscopic imaging system 100.

[0068] Based on the description of the above embodiments, more specific embodiments and drawings are presented below for detailed description.

[0069] First embodiment

[0070] Please refer to Figures 1 to 5 , Figure 1As a schematic diagram of the microscopic imaging system 100 in the first embodiment, the microscopic imaging system 100 comprises, in order from the object side to the image side along the optical axis 110, an aperture stop ST, a first lens L1 having positive refractive power, a second lens L2 having positive refractive power, a third lens L3 having negative refractive power, a fourth lens L4 having positive refractive power, and a fifth lens L5 having positive refractive power. Figure 2 As a spherical aberration curve of the microscopic imaging system 100 in the first embodiment. Figure 3 As a curve of astigmatism and distortion of the microscopic imaging system 100 in the first embodiment. Figure 4 As a geometric aberration diagram of the microscopic imaging system 100 in the first embodiment. Figure 5 As a modulation function diagram of the microscopic imaging system 100 in the first embodiment.

[0071] The object side surface S1 of the first lens L1 is concave at the paraxial region, and the image side surface S2 is convex at the paraxial region;

[0072] The object side surface S3 of the second lens L2 is convex at the paraxial region, and the image side surface S4 is convex at the paraxial region;

[0073] The object side surface S5 of the third lens L3 is concave at the paraxial region, and the image side surface S6 is concave at the paraxial region;

[0074] The object side surface S7 of the fourth lens L4 is concave at the paraxial region, and the image side surface S8 is convex at the paraxial region;

[0075] The object side surface S9 of the fifth lens L5 is convex at the paraxial region, and the image side surface S10 is convex at the paraxial region.

[0076] The object side surface and the image side surface of the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, and the fifth lens L5 are spherical surfaces.

[0077] The material of the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, and the fifth lens L5 is glass.

[0078] Further, the microscopic imaging system 100 satisfies the condition formula: f1 / f2=4.83. Wherein, f1 is the effective focal length of the first lens L1, and f2 is the effective focal length of the second lens L2. When the above condition formula is satisfied, the focal lengths of the first lens L1 and the second lens L2 can be reasonably configured, which helps to correct the imaging distortion and astigmatism of the microscopic imaging system 100, thereby improving the imaging quality of the system.

[0079] Microscopic imaging system 100 satisfies the conditional expression: CRA < 1.5°. CRA is the principal ray incident angle at the maximum field of view of microscopic imaging system 100. Satisfying this relationship reduces the principal ray incident angle on the imaging surface, enabling compatibility with more demanding photosensitive elements. This facilitates assembly of microscopic imaging system 100 and the photosensitive element, thereby improving the overall imaging quality of microscopic imaging system 100.

[0080] The microscopic imaging system 100 satisfies the conditional formula: NA = 0.15, where NA is the numerical aperture of the microscopic imaging system 100. When the above relationship is satisfied, the light flux of the microscopic imaging system 100 is improved and the imaging quality is guaranteed.

[0081] The microscopic imaging system 100 satisfies the conditional formula: TTL / ImgH=10.81. Wherein, TTL is the distance from the object side surface of the first lens L1 to the imaging surface of the microscopic imaging system 100 on the optical axis 110, and ImgH is half the diagonal length of the effective pixel area of ​​the microscopic imaging system 100 on the imaging surface. By controlling the ratio of the total optical length of the microscopic imaging system 100 to half the image height corresponding to the maximum field angle of the microscopic imaging lens, the microscopic imaging system 100 can be miniaturized and compact in structure, with higher imaging quality, showing more details on the object side while ensuring the size range of the imaging surface, thereby facilitating matching with higher-pixel photosensitive elements and obtaining higher imaging quality. This balances miniaturization and better imaging effects, making the structure more compact compared to traditional microscope lenses.

[0082] The microscopic imaging system 100 satisfies the following conditional equation: TTL / f=2.70. TTL is the distance from the object-side surface of the first lens L1 to the imaging plane of the microscopic imaging system 100 on the optical axis 110, and f is the total effective focal length of the microscopic imaging system 100. Meeting this conditional equation facilitates shortening the overall length of the microscopic imaging system 100, achieving a miniaturized and compact design.

[0083] The microscopic imaging system 100 satisfies the following conditional equation: ImgH / ObjH = 1.62. ObjH is half the object height corresponding to the maximum field of view of the microscopic imaging system 100. In this equation, the ratio of ImgH to ObjH represents the magnification. Setting the magnification to 1.62 ensures that the microscopic imaging system 100 maintains a compact and miniaturized design while also meeting design parameter requirements.

[0084] In addition, the parameters of the microscopic imaging system 100 of the first embodiment are shown in Table 1. In Table 1, the surface sequence number S0 can be understood as the object plane of the microscopic imaging system 100, and the surface sequence number S11 can be understood as the image plane of the microscopic imaging system 100. The elements from the object plane S0 to the image plane S11 are arranged in the order of the elements from top to bottom in Table 1. The Y radius in Table 1 is the radius of curvature of the corresponding object side surface or image side surface at the optical axis 110. The surface sequence number 1 and the surface sequence number 2 are the object side surface S1 and the image side surface S2 of the first lens L1, respectively, that is, in the same lens, the surface with the smaller surface sequence number is the object side surface, and the surface with the larger surface sequence number is the image side surface. The first value in the "thickness" parameter column of the first lens L1 is the thickness of the lens on the optical axis 110, and the second value is the distance from the image side surface of the lens to the object side surface of the next lens in the image side direction on the optical axis 110.

[0085] In the first embodiment, the total effective focal length f of the microscopic imaging system 100 is 12 mm, the object field of view FOV is 3.7 mm, the image field of view is 6 mm, and the distance TTL of the object side surface S1 to the image plane S11 of the first lens L1 on the optical axis 110 is 32.42 mm. It can be understood that the units of the Y radius and the thickness in Table 1 are mm, and the unit of the refractive power is 1 / m.

[0086] Table 1

[0087]

[0088] Please refer to Figure 2 , Figure 2 The ray ball diagram of the microscopic imaging system 100 in the first embodiment at wavelengths of 486 nm, 588 nm, and 656 nm is shown. Figure 2 In the ray ball diagram, the abscissa along the X axis represents the focal point shift, and the ordinate along the Y axis represents the normalized field of view, which is the same in other embodiments. From the ray ball diagram, it can be seen that the microscopic imaging system 100 in the first embodiment has a good imaging quality. Figure 2 It can be seen that the spherical aberration value of the microscopic imaging system 100 in the first embodiment is relatively optimal, indicating that the imaging quality of the microscopic imaging system 100 in the embodiment is better.

[0089] Please refer to Figure 3 the left side of the figure, which is the ray astigmatism diagram of the microscopic imaging system 100 in the first embodiment at wavelengths of 486.1 nm, 587.6 nm, and 656.3 nm. In the ray astigmatism diagram, the abscissa along the X axis represents the focal point shift, and the ordinate along the Y axis represents the image height, which is the same in other embodiments. It can be seen that the astigmatism of the microscopic imaging system 100 is well compensated, and the imaging quality is improved to a certain extent.

[0090] Please refer to Figure 3The right-hand figure in FIG shows the distortion curves of the microscopic imaging system 100 of the first embodiment at wavelengths of 486.1 nm, 587.6 nm, and 656.3 nm. The abscissa along the X-axis represents distortion, and the ordinate along the Y-axis represents image height, which is the same for the other embodiments. It can be seen that at wavelengths of 486.1 nm, 587.6 nm, and 656.3 nm, the distortion of the microscopic imaging system 100 does not exceed 1.2%, indicating that the microscopic imaging system 100 has achieved a good distortion correction effect.

[0091] Combined with reference Figure 4 and Figure 5 , it can be seen that the imaging effect of the microscopic imaging system 100 is relatively ideal and can ensure good imaging quality.

[0092] Second embodiment

[0093] Please refer to Figure 6 , is a schematic diagram of a microscopic imaging system 100 in a second embodiment. The microscopic imaging system 100 includes, in order from the object side to the image side along the optical axis 110, a first lens L1 with positive refractive power, an aperture ST, a second lens L2 with positive refractive power, a third lens L3 with negative refractive power, a fourth lens L4 with positive refractive power, and a fifth lens L5 with positive refractive power. Figure 7 is a spherical aberration curve diagram of the microscopic imaging system 100 in the second embodiment. Figure 8 From left to right are graphs of astigmatism and distortion of the microscopic imaging system 100 in the second embodiment. Figure 9 is a geometric aberration diagram of the microscopic imaging system 100 in the second embodiment. Figure 10 is a modulation function diagram of the microscopic imaging system 100 in the second embodiment.

[0094] The object-side surface S1 of the first lens L1 is concave at the paraxial direction, and the image-side surface S2 is convex at the paraxial direction.

[0095] The object-side surface S3 of the second lens L2 is convex at the paraxial direction, and the image-side surface S4 is convex at the paraxial direction.

[0096] The object-side surface S5 of the third lens L3 is concave at the paraxial position, and the image-side surface S6 is concave at the paraxial position.

[0097] The object-side surface S7 of the fourth lens L4 is concave at the paraxial direction, and the image-side surface S8 is convex at the paraxial direction.

[0098] The object-side surface S9 of the fifth lens L5 is convex at the paraxial position, and the image-side surface S10 is also convex at the paraxial position.

[0099] The object-side surfaces and image-side surfaces of the first lens L1 , the second lens L2 , the third lens L3 , the fourth lens L4 , and the fifth lens L5 are all spherical surfaces.

[0100] The first lens L1 , the second lens L2 , the third lens L3 , the fourth lens L4 , and the fifth lens L5 are all made of glass.

[0101] In addition, various parameters of the microscopic imaging system 100 are given in Table 2, and the definitions of the parameters can be obtained from the first embodiment, which will not be repeated here.

[0102] Table 2

[0103]

[0104] According to the parameter information provided above, the following relationship can be derived:

[0105] f1 / f2=5.35; CRA<1.5°; NA=0.15; TTL / ImgH=15.25; TTL / f=3.13;

[0106] ImgH / ObjH=1.54.

[0107] Third embodiment

[0108] Please refer to Figure 11 , is a schematic diagram of a microscopic imaging system 100 in a third embodiment. The microscopic imaging system 100 includes, in order from the object side to the image side along the optical axis 110, a first lens L1 with positive refractive power, a second lens L2 with positive refractive power, an aperture ST, a third lens L3 with negative refractive power, a fourth lens L4 with positive refractive power, and a fifth lens L5 with positive refractive power. Figure 12 is a spherical aberration curve diagram of the microscopic imaging system 100 in the third embodiment. Figure 13 From left to right are graphs of astigmatism and distortion of the microscopic imaging system 100 in the third embodiment. Figure 14 is a geometric aberration diagram of the microscopic imaging system 100 in the third embodiment. Figure 15 is a modulation function diagram of the microscopic imaging system 100 in the second embodiment.

[0109] The object-side surface S1 of the first lens L1 is concave at the paraxial direction, and the image-side surface S2 is convex at the paraxial direction.

[0110] The object-side surface S3 of the second lens L2 is convex at the paraxial direction, and the image-side surface S4 is convex at the paraxial direction.

[0111] The object-side surface S5 of the third lens L3 is concave at the paraxial position, and the image-side surface S6 is concave at the paraxial position.

[0112] The object-side surface S7 of the fourth lens L4 is concave at the paraxial direction, and the image-side surface S8 is convex at the paraxial direction.

[0113] The object-side surface S9 of the fifth lens L5 is convex at the paraxial position, and the image-side surface S10 is also convex at the paraxial position.

[0114] The object-side surfaces and image-side surfaces of the first lens L1 , the second lens L2 , the third lens L3 , the fourth lens L4 , and the fifth lens L5 are all spherical surfaces.

[0115] The first lens L1 , the second lens L2 , the third lens L3 , the fourth lens L4 , and the fifth lens L5 are all made of glass.

[0116] In addition, various parameters of the microscopic imaging system 100 are given in Table 3, and the definitions of the parameters can be obtained from the first embodiment, which will not be repeated here.

[0117] Table 3

[0118]

[0119] According to the parameter information provided above, the following relationship can be derived:

[0120] f1 / f2=19.04; CRA<1.5°; NA=0.15; TTL / ImgH=18.36; TTL / f=3.21;

[0121] ImgH / ObjH=1.55.

[0122] See Figure 16 In some embodiments, the microscopic imaging system 100 can be assembled with a photosensitive element 210 to form a microscopic imaging module 200, and the photosensitive element 210 is arranged on the image side of the microscopic imaging system 100. In this case, the photosensitive surface of the photosensitive element 210 can be regarded as the image surface of the microscopic imaging system 100. Specifically, the photosensitive element 210 can be a charge coupled device (CCD) or a complementary metal oxide semiconductor device (CMOS Sensor). The microscopic imaging system 100 is used in the microscopic imaging module 200. Since the microscopic imaging system 100 has the characteristics of a short total length, excellent imaging effect, and compact structure, the microscopic imaging module 200 can be compactly designed and can ensure excellent imaging quality.

[0123] In some embodiments, the microscopic imaging module 200 can be used in a microscopic imaging device, which includes a housing and the microscopic imaging module 200, wherein the microscopic imaging module 200 is disposed within the housing. Using the microscopic imaging module 200 in the microscopic imaging device facilitates a compact design of the microscopic imaging device and ensures superior imaging quality. Of course, the microscopic imaging system 100 can also be used in the microscopic imaging device. When the microscopic imaging device includes a PCB board, the use of a miniaturized, compact microscopic imaging system 100 or microscopic imaging module 200 can save space on the PCB board, allowing the board to accommodate more devices.

[0124] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0125] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be determined by the appended claims.

Claims

1. A microscopic imaging system, characterized in that: The number of lenses with refractive power in the microscopic imaging system is five, including a first lens, a second lens, a third lens, a fourth lens, and a fifth lens arranged in sequence from the object side to the image side along the optical axis; The object side surface of the first lens is concave at the paraxial position, and the image side surface is convex at the paraxial position; the object side surface of the second lens is convex at the paraxial position, and the image side surface is convex at the paraxial position; the object side surface of the third lens is concave at the paraxial position, and the image side surface is concave at the paraxial position; the object side surface of the fourth lens is concave at the paraxial position, and the image side surface is convex at the paraxial position; the object side surface of the fifth lens is convex at the paraxial position, and the image side surface is convex at the paraxial position; the first lens has positive refractive power, the second lens has positive refractive power, the third lens has negative refractive power, the fourth lens has positive refractive power, and the fifth lens has positive refractive power; And the microscopic imaging system satisfies the following conditional formula: 10.50<TTL / ImgH<18.50; Wherein, TTL is the distance from the object side of the first lens to the imaging plane of the microscopic imaging system on the optical axis, and ImgH is half the diagonal length of the effective pixel area of ​​the microscopic imaging system on the imaging plane; The following conditions are also met: 4.80<f1 / f2<19.10; Wherein, f1 is the effective focal length of the first lens, and f2 is the effective focal length of the second lens.

2. The microscopic imaging system according to claim 1, wherein: The following conditions are met: CRA<1.5°; Wherein, CRA is the chief ray incident angle of the microscopic imaging system; and / or, 0.14<NA<0.16; Wherein, NA is the numerical aperture of the microscopic imaging system.

3. The microscopic imaging system according to claim 1, characterized in that The following conditions are met: 2.50<TTL / f<3.30; Wherein, TTL is the distance from the object side surface of the first lens to the imaging surface of the microscopic imaging system on the optical axis, and f is the total effective focal length of the microscopic imaging system.

4. The microscopic imaging system according to claim 1, wherein: The following conditions are met: 1.5<ImgH / ObjH<1.7; Wherein, ObjH is half of the object height corresponding to the maximum field angle of the microscopic imaging system.

5. The microscopic imaging system according to claim 1, wherein: The ratio of the refractive index to the Abbe number of the first lens, the ratio of the refractive index to the Abbe number of the second lens, the ratio of the refractive index to the Abbe number of the third lens, the ratio of the refractive index to the Abbe number of the fourth lens, and the ratio of the refractive index to the Abbe number of the fifth lens are 1.55 / 45.8, 1.62 / 60.3, 1.81 / 25.4, 1.62 / 60.3, and 1.68 / 55.2, respectively. The allowable tolerance is 10%, the upper deviation is +5%, and the lower deviation is -5%.

6. The microscopic imaging system according to claim 1, wherein: Also includes the aperture, Wherein, the aperture is provided coaxially between the object side and the first lens; and / or, The aperture is coaxially arranged between the first lens and the second lens; and / or, The aperture is coaxially arranged between the second lens and the third lens.

7. A microscopic imaging module, characterized in that: The invention comprises a photosensitive element and the microscopic imaging system according to any one of claims 1 to 6, wherein the photosensitive element is arranged on the image side of the microscopic imaging system.

8. A microscopic imaging device, characterized in that: It comprises a shell and the microscopic imaging module according to claim 7, wherein the microscopic imaging module is arranged in the shell.

Images