Objective lens module, endoscope and endoscope imaging equipment

Abstract

An objective lens module is applied to an endoscope, the objective lens module comprises a first lens group with negative focal power and a second lens group with positive focal power, the first lens group comprises a negative lens and a turning lens used for realizing light path deflection, and the second lens group comprises a positive lens and a negative lens. The negative lens, the turning lens and the second lens group are sequentially arranged from the object side to the image side in the optical axis direction of the endoscope; the objective lens module further comprises a diaphragm and a third lens group, the third lens group comprises an actuator and an optical component with variable focal power, and the optical component and the diaphragm are arranged between the first lens group and the second lens group. The actuator is configured to apply a force to the optical member to change a shape of a solid lens in the optical member so that the solid lens can be changed from a first shape having a first refractive power to a second shape having a second refractive power and held.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to an objective lens module, an endoscope, and an endoscopic imaging device. Background Art

[0002] With the rapid development of medical equipment, endoscopes are increasingly used in the medical field. Endoscopes can be inserted into the user's body to obtain images of the lesion area in the user's body for diagnosis or treatment. The imaging quality of the endoscope affects the accuracy of diagnosis and treatment, especially when dealing with tissues at different distances, the focusing function of the endoscope is more needed.

[0003] Among them, the volume and imaging quality of the endoscope are mutually constrained. A small volume means sacrificing the imaging quality of the optical system, while a large volume improves the imaging quality of the endoscope by increasing the number of lenses. The focusing function of the endoscope is achieved by moving the distance of the lenses, which not only requires sophisticated and complex processing of the endoscope and high production costs; but also is not conducive to the miniaturization of the endoscope and easily affects the imaging quality of the endoscope. Summary of the Invention

[0004] The present invention provides an objective lens module, an endoscope, and an endoscope imaging device, which can achieve zoom by changing the shape of a solid lens, thereby meeting the miniaturization requirements of the endoscope and ensuring the imaging quality of the endoscope, and is beneficial to the current trend of miniaturization of endoscopes.

[0005] According to a first aspect of the present invention, there is provided an objective lens module for use in an endoscope, the objective lens module comprising a first lens group having negative optical power and a second lens group having positive optical power, the first lens group comprising a negative lens and a deflection mirror for deflecting an optical path, the negative lens, the deflection mirror, and the second lens group being arranged in sequence from the object side to the image side along the optical axis of the endoscope;

[0006] In which, the objective lens module also includes an aperture and a third lens group, the third lens group includes an actuator and an optical component with variable optical focal length, the optical component and the aperture are arranged between the first lens group and the second lens group, and the actuator is used to apply force to the optical component to change the shape of the solid lens in the optical component, so that the solid lens can change from a first shape with a first optical focal length to a second shape with a second optical focal length and maintain it.

[0007] In an objective lens module of one embodiment of the present invention, the optical component includes a flexible lens cover, a lens seat and the solid lens, the solid lens is arranged between the lens cover and the lens seat, and the actuator is arranged on the flexible lens cover for applying force to the solid lens to deform the solid lens.

[0008] In the objective lens module according to one embodiment of the present invention, the solid lens has a first optical axis parallel to the optical axis of the endoscope, and an extension line of the first optical axis is perpendicular to at least a portion of the surface of the lens holder.

[0009] In the objective lens module according to one embodiment of the present invention, the actuator includes a piezoelectric element located outside the solid lens. The piezoelectric element is provided on the lens cover and can deform the lens cover and the solid lens when energized.

[0010] In the objective lens module of one embodiment of the present invention, the piezoelectric element includes an actuating ring arranged on the lens cover, the inner diameter of the actuating ring is not less than the outer diameter of the solid lens, and the outer diameter of the actuating ring is not greater than the outer diameter of the lens cover.

[0011] In the objective lens module of one embodiment of the present invention, the lens seat is a lens seat made of rigid glass; and / or the lens cover is a lens cover made of a flexible thin glass film; and the solid lens is a solid lens made of a deformable transparent polymer.

[0012] In an objective lens module according to an embodiment of the present invention, the total focal length of the objective lens module is f, the focal length of the first lens group is f1, and f1 and f satisfy the relationship: f1 / f>-1.8; and / or,

[0013] The total focal length of the objective lens module is f, the focal length of the second lens group is f2, and f2 and f satisfy the relationship: f2 / f<2.5.

[0014] In the objective lens module of one embodiment of the present invention, the negative lens includes a first meniscus lens, a convex surface of the first meniscus lens is close to the object side, and a concave surface of the first meniscus lens is close to the image side.

[0015] In the objective lens module according to one embodiment of the present invention, the turning mirror includes a turning prism, and the turning angle of the turning prism is 0 degree, 30 degrees, or 45 degrees.

[0016] In the objective lens module of one embodiment of the present invention, the second lens group includes at least one cemented lens formed by gluing, and the cemented lens is arranged on the side of the third lens group close to the image side along the optical axis direction to balance the chromatic aberration of the objective lens module.

[0017] In the objective lens module of one embodiment of the present invention, the cemented lens includes a first cemented lens and a second cemented lens, and the first cemented lens and the second cemented lens are arranged in sequence from the object side to the image side along the optical axis.

[0018] In an objective lens module according to one embodiment of the present invention, the first cemented lens includes a first biconvex lens and a second meniscus lens, and the second meniscus lens is cemented to the first biconvex lens by a cementing material and arranged in sequence from the object side to the image side along the optical axis.

[0019] In the objective lens module of one embodiment of the present invention, the second cemented lens includes a second biconvex lens and a third meniscus lens, and the second biconvex lens is cemented with the third meniscus lens through a cementing material and arranged in sequence from the object side to the image side along the optical axis.

[0020] In the objective lens module according to one embodiment of the present invention, the cemented lens further includes a plano-convex lens, and the plano-convex lens is arranged on a side of the first cemented lens close to the object side.

[0021] According to a second aspect of the present invention, the present invention further provides an endoscope, comprising a tube body and the above-mentioned objective lens module, wherein the objective lens module is arranged in the tube body.

[0022] According to a third aspect of the present invention, the present invention further provides an endoscopic imaging device, characterized in that it comprises a display and the above-mentioned endoscope, wherein the display is used to display images acquired by the endoscope.

[0023] The technical solution provided by the embodiments of the present application may include the following beneficial effects: The present application designs an objective lens module, an endoscope, and an endoscope imaging device, comprising a first lens group, a second lens group, an aperture, and a third lens group, wherein the first lens group, the aperture, the third lens group, and the second lens group are arranged in sequence from the object side to the image side along the optical axis direction of the endoscope. Among them, the first lens group has a negative optical focal length, which can effectively couple light with a larger field of view into the objective lens module, thereby increasing the field of view angle of the objective lens module and shortening the total optical length of the objective lens module; the second lens group has a positive optical focal length, which helps to reduce the incident angle of light on the surface of the second lens group, further compressing the main light angle, while also correcting aberrations, and can match with an image sensor with a larger main light angle, thereby improving imaging quality.

[0024] Among them, the third lens group includes an actuator and an optical component with variable optical focal length. The optical component and the aperture are arranged between the first lens group and the second lens group. The actuator is used to apply force to the optical component to change the shape of the solid lens in the optical component, so that the solid lens can change from a first shape with a first optical focal length to a second shape with a second optical focal length and maintain it to realize the zoom function of the objective lens module. There will be no transmission problems in the mechanical structure, and there will be no coma problems caused by gravity. It not only meets the miniaturization requirements of the endoscope, but also ensures the imaging quality of the endoscope, which is beneficial to the current trend of miniaturization of endoscopes.

[0025] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0027] Figure 1 1 is a schematic structural diagram of an objective lens module provided in one embodiment of the present application;

[0028] Figure 2 This is the MTF curve of the objective lens module of the present application when the object distance is equal to 20 mm;

[0029] Figure 3 This is the MTF curve of the objective lens module of the present application when the object distance is equal to 50mm;

[0030] Figure 4 This is the MTF curve of the objective lens module of the present application when the object distance is equal to 150 mm;

[0031] Figure 5 It is a schematic structural diagram of the optical component of the present application.

[0032] Description of reference numerals:

[0033] 100, first lens group; 200, second lens group; 300, third lens group; 301, actuator; 400, aperture;

[0034] 10. First meniscus lens; 20. Turning prism; 30. Optical component; 31. Solid lens; 32. Lens holder; 33. Flexible lens cover; 34. Piezoelectric element; 40. Second meniscus lens; 50. First biconvex lens; 60. Second biconvex lens; 70. Third meniscus lens; 80. Plano-convex lens. DETAILED DESCRIPTION

[0035] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0036] It should also be understood that the terms used in this specification of the present invention are only for the purpose of describing specific realities. In the description of this application, 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" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limiting this application. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, features defined as "first" and "second" may explicitly or implicitly include one or more of the said features. In the description of this application, "multiple" means two or more, unless otherwise clearly and specifically defined.

[0037] The following describes some embodiments of the present application in detail with reference to the accompanying drawings. In the absence of conflict, the following embodiments and features therein may be combined with each other.

[0038] like Figures 1 to 5 As shown, according to a first aspect of the present application, the present application provides an objective lens module for use in an endoscope, the objective lens module comprising a first lens group 100 and a second lens group 200, the first lens group 100 and the second lens group 200 being arranged in sequence from the object side to the image side along the optical axis direction of the endoscope, the first lens group 100 being used to generate a real image of a detected target; Figure 1 As shown, the left side is the object side and the right side is the image side. The first lens group 100 has negative power, effectively coupling light from a larger field of view into the objective lens module, thereby increasing the objective lens module's field of view angle and shortening its overall optical length. The second lens group 200 has positive power, which helps reduce the angle of incidence of light on the surface of the second lens group 200, further compressing the principal ray angle while also correcting aberrations. It also enables compatibility with image sensors with larger principal ray angles, thereby improving image quality. Furthermore, the negative power of the first lens group 100 and the positive power of the second lens group 200 help suppress astigmatism and field curvature.

[0039] In an optional embodiment, if Figure 1 and Figure 5As shown, the first lens group 100 includes a negative lens and a steering mirror for realizing light path deflection. The negative lens, the steering mirror and the second lens group 200 are arranged in sequence from the object side to the image side along the optical axis direction of the endoscope. The negative lens can obtain the wide viewing angle required by the endoscope and ensure the back focus, mainly to reduce the projection angle of the incident light with a high field of view angle to the rear steering mirror, so as to achieve a large field of view angle. The steering mirror is used to change the viewing angle of the objective lens module so that the target that is not within the field of view directly in front of the mirror body can be observed by deflecting the optical axis, thereby improving the observation range. Combined with the second lens group 200 with positive optical power, it is beneficial to correct the magnification chromatic aberration and suppress the increase in the total length of the objective lens module, thereby reducing the size of the objective lens module.

[0040] In an optional embodiment, the second lens group 200 is composed of multiple lenses, which is conducive to balancing the aberrations of each field of view and can effectively correct astigmatism, relative illumination, chromatic aberration and distortion, ensuring that the obtained image data is suitable for conversion and achieving a three-dimensional effect.

[0041] In an optional embodiment, the objective lens module also includes a third lens group 300, which includes an actuator 301 and an optical component 30 with variable optical focal length. The optical component 30 is arranged between the first lens group 100 and the second lens group 200. The actuator 301 is used to apply force to the optical component 30 to change the shape of the solid lens 31 in the optical component 30, so that the solid lens 31 can change from a first shape with a first optical focal length to a second shape with a second optical focal length and maintain it, which not only meets the miniaturization requirements of the endoscope, but also ensures the imaging quality of the endoscope, which is beneficial to the current trend of miniaturization of endoscopes.

[0042] Among them, most endoscopes adopt a tubular structure, and at the same time, it also avoids the patient from having irritation or other unpleasant experiences when the endoscope is placed in the patient's body. The volume of the endoscope tends to be miniaturized as much as possible. Generally, the outer diameter of the endoscope does not exceed 10 mm. However, the volume and imaging quality of the endoscope are mutually constrained. A smaller volume usually means sacrificing the imaging quality of the optical system, especially when it is necessary to increase the zoom function of the endoscope to cope with tissues at different distances in complex surgical scenarios. Therefore, the present application applies an optical component 30 with variable optical focal length to the endoscope, which can meet the miniaturization design requirements of the endoscope, and while ensuring the imaging quality of the endoscope, it can also achieve an optical zoom function by changing the shape of the solid lens 31, so that the endoscope can image tissues at different distances in complex surgical scenarios. Compared with endoscopes that achieve zoom by moving lenses, the endoscope of the present invention is more reliable, there will be no transmission problems in the mechanical structure, no processing complexity of precision mechanical structures, no mechanical wear, and even the overall structural size of the endoscope can be reduced. Compared with endoscopes that achieve zoom by using liquid lenses, the endoscope of the present invention is not affected by gravity and liquid temperature, and can achieve zoom of different focal lengths under the control of actuator 301, that is, the deformation of solid lens 31 is related to the torque of actuator 301, can be controlled manually, and is not affected by gravity and temperature, which can avoid spherical aberration and coma problems during endoscopic imaging due to the effect of gravity.

[0043] In an optional embodiment, the objective lens module further includes an aperture 400, which is disposed between the first lens assembly 100 and the second lens group 200. More specifically, the aperture 400 can be disposed between the optical structure 30 and the second lens group 200 to limit the size of the incident light beam. The aperture 400 can be made of a black light-shielding material to eliminate stray light and thereby improve image clarity of the objective lens module.

[0044] Illustratively, aperture 400 is a light hole that selects the passage of a light beam, and the area outside the aperture is black. Aperture 400 acts as a hole that limits the size of the incident light beam. The size of aperture 400 can improve the resolution, light transmission, and depth of field of the imaging lens. In this embodiment, the diameter of aperture 400 ranges from 0.6 mm to 1.3 mm.

[0045] In an optional embodiment, the negative lens, the turning mirror, the aperture 400, the third lens group 300 and the second lens group 200 are arranged in sequence from the object side to the image side along the optical axis of the endoscope, and the center points of the negative lens, the turning mirror, the aperture 400, the third lens group 300 and the second lens group 200 are all located on the same straight line.

[0046] In an optional embodiment, if Figure 5 As shown, the optical component 30 includes a flexible lens cover 33, a lens holder 32 and a solid lens 31. The solid lens 31 is arranged between the lens cover and the lens holder 32. The actuator 301 is arranged on the flexible lens cover 33 and is used to apply force to the solid lens 31 to deform the solid lens 31, thereby realizing the change of the focal length of the solid lens 31.

[0047] In an optional embodiment, the solid lens 31 has a first optical axis parallel to the optical axis of the endoscope, and the extension line of the first optical axis is perpendicular to at least a portion of the surface of the lens holder 32, so that the central portion of the solid lens 31 convexes upward or concave downward, forming a plano-convex lens or a plano-concave lens with variable optical focal length, thereby achieving zooming of another focal length; at the same time, the shape of the convexity or concaveness is independent of the gravity of the solid lens 31, thereby avoiding the influence of the gravity of the solid lens 31 on imaging; in addition, the deformation of the solid lens 31 is controlled by the actuator 301, which can effectively reduce the coma and spherical aberration of the solid lens 31.

[0048] In an optional embodiment, the actuator 301 includes a piezoelectric element 34 located outside the solid lens 31. The piezoelectric element 34 is arranged on the lens cover and can deform the lens cover and the solid lens 31 when energized, thereby causing the central portion of the solid lens 31 to convex upward or concave downward to form a plano-convex or plano-concave lens with variable optical focal length.

[0049] For example, when a predetermined voltage is applied to the piezoelectric element 34 to form an electric field, the piezoelectric element 34 expands or contracts on the lens cover. The lens cover elastically deforms as the piezoelectric element 34 expands or contracts, and the solid lens 31 deforms as the lens cover deforms, thereby forming a variable-focus optical member 30. The lens cover and the piezoelectric element 34 may be bonded together using an adhesive. The piezoelectric element 34 may be designed based on the principle of a lever to fully transmit the force generated by the deformation of the piezoelectric element 34 to the lens cover and the solid lens 31, causing the center portion of the solid lens 31 to convex upward or concave downward, thereby forming a plano-convex or plano-concave lens with variable optical power.

[0050] In an optional embodiment, the piezoelectric element 34 includes an actuating ring arranged on the lens cover, the inner diameter of the actuating ring is not less than the outer diameter of the solid lens 31, and the outer diameter of the actuating ring is not larger than the outer diameter of the lens cover, just like a circular arc can be formed around the central axis of the lens cover or the solid lens 31. In this way, pressure can be transmitted to the lens cover and the solid lens 31 more accurately, so that the actuating ring will not swing left and right when transmitting pressure on the surface of the lens cover. It is also beneficial to the miniaturized design of the endoscope and can also realize the optical zoom function.

[0051] In an optional embodiment, the lens holder 32 is made of rigid glass.

[0052] In an optional embodiment, the lens cover is made of a flexible thin glass film.

[0053] In an optional embodiment, the solid lens 31 is a solid lens 31 made of a deformable transparent polymer.

[0054] In an optional embodiment, the total focal length of the objective lens module is f, the focal length of the first lens group 100 is f1, and f1 and f satisfy the relationship: f1 / f>-1.8. Not only can a field of view angle greater than 60 degrees and a variable viewing angle be achieved, but the light can also be strongly turned, and the angle of the main light can be quickly reduced.

[0055] In an optional embodiment, the total focal length of the objective lens module is f, the focal length of the second lens group 200 is f2, and f2 and f satisfy the relationship: f2 / f<2.5; not only can a basically uniform image plane illumination be obtained, but the light can also be deflected to achieve a good CRA.

[0056] In an optional embodiment, if Figure 1 As shown, in order to reduce the spherical aberration of the objective lens module and improve the imaging quality of the objective lens module, the negative lens includes a first meniscus lens 10, the convex surface of the first meniscus lens 10 is close to the object side, and the concave surface of the first meniscus lens 10 is close to the image side; at the same time, the first meniscus lens 10 is more advantageous for correcting magnification chromatic aberration.

[0057] In an optional embodiment, the steering mirror includes a steering prism 20. The steering prism 20 can be an optical element or a combination of multiple optical elements. The steering prism 20 can change the direction of the light path based on principles such as reflection or refraction to adapt to different usage scenarios.

[0058] In some embodiments, the turning angle of the turning prism 20 is 0 degrees, and it does not have the function of deflecting the light path. It can be applied to an endoscope with a viewing angle of 0 degrees to meet different diagnostic needs.

[0059] In some embodiments, the steering prism 20 has a steering angle of 30 degrees, which can be used to deflect the light path by 30 degrees and can be applied to a 30-degree oblique endoscope. The viewing direction of the system is tilted relative to the direction of the oblique endoscope, thereby adapting to different diagnostic needs.

[0060] In some embodiments, the steering prism 20 has a 45-degree steering angle, which can deflect the light path by 30° and can be applied to a 45-degree oblique endoscope. The system's viewing direction is tilted relative to the body of the oblique endoscope, thus adapting to different diagnostic needs.

[0061] It should be noted that, according to different diagnostic requirements, the steering prism 20 can also be configured to be able to change the light path to any other angle, including but not limited to 0 degrees, 30 degrees, or 45 degrees.

[0062] In an optional embodiment, the aperture 400 and the steering prism 20 are arranged closely together on the side close to the image side, and the light can be reflected in the steering prism 20 so that the light beam passes through the hole of the aperture 400. When the objective lens module is configured with the steering prism 20 to change the viewing angle, the influence of the steering prism 20 on the entrance pupil diameter of the objective lens module can be avoided, thereby effectively increasing the entrance pupil diameter of the objective lens module, thereby improving the light energy utilization rate and imaging brightness of the objective lens module, and also achieving the purpose of eliminating stray light, thereby improving the clarity of the image.

[0063] In an optional embodiment, the bottom surface of the turning prism 20 is coated with a highly reflective coating to increase the reflectivity of incident light at low angles, thereby improving light energy utilization. The prism is made of a high-refractive-index material to reduce the critical angle for total internal reflection, allowing more optical fibers to reflect. The bottom surface is coated with a highly reflective coating, while the light-transmitting surface is coated with a highly transparent coating, thereby increasing light throughput.

[0064] In an optional embodiment, second lens group 200 includes at least one cemented lens, which is positioned on the image side of third lens group 300 along the optical axis to balance chromatic aberration within the objective lens module. Furthermore, the cemented lens can compensate for aberration changes within the objective lens system during zooming, thereby achieving high-quality image resolution.

[0065] In an optional embodiment, the cemented lens includes a first cemented lens and a second cemented lens, and the first cemented lens and the second cemented lens are arranged in sequence from the object side to the image side along the optical axis. This not only reduces the overall structural size of the endoscope, avoids the center alignment problem between multiple lenses and the image sensor, reduces the difficulty of assembling the second lens group 200, but also is conducive to the miniaturized design of the endoscope.

[0066] In an optional embodiment, the first cemented lens includes a first biconvex lens 50 and a second meniscus lens 40, and the second meniscus lens 40 is cemented to the first biconvex lens 50 through a cementing material and arranged in sequence from the object side to the image side along the optical axis.

[0067] In an optional embodiment, the second cemented lens includes a second biconvex lens 60 and a third meniscus lens 70. The second biconvex lens 60 is cemented to the third meniscus lens 70 through a cementing material and is sequentially arranged along the optical axis from the object side to the image side.

[0068] In an optional embodiment, the cemented lens further includes a plano-convex lens, and the plano-convex lens is arranged on a side of the first cemented lens close to the object side.

[0069] Therefore, the objective lens module of the above-mentioned endoscope can improve the field of view of the objective lens module through the design of the optical focal length and surface shape of each lens and the setting of the double-cemented lens, so that the objective lens module can meet the needs of large-scale imaging. At the same time, it can also enable the objective lens module to have good imaging quality in different wavelength ranges, which is beneficial to improving the diagnostic efficiency and accuracy of the endoscope.

[0070] like Figure 2 It can be seen that the MTF curve of the objective lens module of the present application is when the object distance is equal to 20 mm; Figure 3 It can be seen that the MTF curve of the objective lens module of the present application is when the object distance is equal to 50 mm; Figure 4 It can be seen from the MTF curve of the objective lens module of the present application when the object distance is equal to 150 mm; that is, through the MTF curve of the objective lens module of the present application at different focuses, the field curvature of the objective lens module can be effectively corrected, and the system has good imaging quality.

[0071] Table 1 below shows an objective lens module according to one embodiment, and the normalized focal length parameters of the objective lens module, wherein the units of the curvature radius, distance, and effective focal length are in mm, as shown in Table 1:

[0072]

[0073]

[0074] Table 1

[0075] Table 2 below shows an objective lens module according to another embodiment, and the normalized focal length parameters of the objective lens module, wherein the units of the curvature radius, distance, and effective focal length are in mm, as shown in Table 2:

[0076]

[0077]

[0078] Total focal length f 1 f before -1.21 f 1.56

[0079] As shown in Table 2

[0080] like Figures 1 to 5 As shown, according to the second aspect of the present application, the present application provides an endoscope, including a tube body and the above-mentioned objective lens module, and the objective lens module is arranged in the tube body.

[0081] like Figures 1 to 5 As shown, according to the third aspect of the present application, the present application also provides an endoscopic imaging device, including a display and the above-mentioned endoscope, and the display is used to display the image obtained by the endoscope.

[0082] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood broadly. For example, they can refer to fixed connections, detachable connections, or integral connections. They can refer to mechanical connections or electrical connections. They can refer to direct connections or indirect connections through an intermediary. They can refer to internal communication between two components or interactions between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0083] In this application, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0084] The disclosure above provides many different embodiments or examples for realizing the different structures of the present application. In order to simplify the disclosure of the present application, the components and settings of specific examples are described above. Of course, they are merely examples and are not intended to limit the present application. In addition, the present application may repeat reference numerals and / or reference letters in different examples, and such repetition is for the purpose of simplicity and clarity, and does not itself indicate the relationship between the various embodiments and / or settings discussed. In addition, the present application provides examples of various specific processes and materials, but those of ordinary skill in the art will appreciate the application of other processes and / or the use of other materials.

[0085] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that a specific feature, structure, material, or characteristic described in conjunction with an embodiment or example is included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Claims

1. An objective lens module, used in an endoscope, characterized in that: The objective lens module includes a first lens group with negative optical power and a second lens group with positive optical power, the first lens group includes a negative lens and a steering mirror for achieving optical path deflection, and the negative lens, the steering mirror and the second lens group are arranged in sequence from the object side to the image side along the optical axis direction of the endoscope; In which, the objective lens module also includes an aperture and a third lens group, the third lens group includes an actuator and an optical component with variable optical focal length, the optical component and the aperture are both arranged between the first lens group and the second lens group, and the actuator is used to apply force to the optical component to change the shape of the solid lens in the optical component, so that the solid lens can change from a first shape with a first optical focal length to a second shape with a second optical focal length and maintain it.

2. The objective lens module according to claim 1, wherein: The optical component includes a flexible lens cover, a lens holder, and the solid lens. The solid lens is disposed between the lens cover and the lens holder. The actuator is disposed on the flexible lens cover and is configured to apply force to the solid lens to deform the solid lens.

3. The objective lens module according to claim 2, wherein: The solid lens has a first optical axis parallel to the optical axis of the endoscope, and an extension line of the first optical axis is perpendicular to at least a portion of the surface of the lens holder.

4. The objective lens module according to claim 2, wherein: The actuator includes a piezoelectric element located outside the solid lens, the piezoelectric element being provided on the lens cover and capable of deforming the lens cover and the solid lens when energized.

5. The objective lens module according to claim 4, characterized in that: The piezoelectric element includes an actuating ring disposed on the lens cover, wherein the inner diameter of the actuating ring is not less than the outer diameter of the solid lens, and the outer diameter of the actuating ring is not greater than the outer diameter of the lens cover.

6. The objective lens module according to any one of claims 2 to 5, characterized in that: The lens seat is a lens seat made of rigid glass; and / or the lens cover is a lens cover made of a flexible thin glass film; and the solid lens is a solid lens made of a deformable transparent polymer.

7. The objective lens module according to claim 1, wherein: The total focal length of the objective lens module is f, the focal length of the first lens group is f1, and f1 and f satisfy the relationship: f1 / f>-1.8; and / or, The total focal length of the objective lens module is f, the focal length of the second lens group is f2, and f2 and f satisfy the relationship: f2 / f<2.

5.

8. The objective lens module according to claim 1, wherein: The negative lens includes a first meniscus lens having a convex surface close to the object side and a concave surface close to the image side.

9. The objective lens module according to claim 1, wherein: The turning mirror includes a turning prism, and the turning angle of the turning prism is 0 degree, 30 degrees, or 45 degrees.

10. The objective lens module according to claim 1, characterized in that: The second lens group includes at least one cemented lens formed by cementing, and the cemented lens is arranged on a side of the third lens group close to the image side along the optical axis direction to balance the chromatic aberration of the objective lens module.

11. The objective lens module according to claim 10, wherein: The cemented lens includes a first cemented lens and a second cemented lens, and the first cemented lens and the second cemented lens are sequentially arranged from the object side to the image side along the optical axis.

12. The objective lens module according to claim 11, wherein: The first cemented lens includes a first biconvex lens and a second meniscus lens. The second meniscus lens is cemented to the first biconvex lens by a cementing material and is sequentially arranged from the object side to the image side along the optical axis.

13. The objective lens module according to claim 11, wherein: The second cemented lens includes a second biconvex lens and a third meniscus lens. The second biconvex lens is cemented to the third meniscus lens through a cementing material and is sequentially arranged from the object side to the image side along the optical axis.

14. The objective lens module according to claim 11, wherein: The cemented lens further includes a plano-convex lens, which is arranged on a side of the first cemented lens close to the object side.

15. An endoscope, characterized in that: It comprises a tube body and the objective lens module according to any one of claims 1 to 14, wherein the objective lens module is arranged in the tube body.

16. An endoscopic imaging device, characterized in that A display and the endoscope according to claim 15 are included, wherein the display is used to display images acquired through the endoscope.

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