CN209821495U - Endoscope and objective lens device - Google Patents

Abstract

An endoscope and its objective lens device, this objective lens device includes front end lens battery, combination prism and is used for fixing the first objective lens tube of front end lens battery and combination prism, the combination prism is set up behind the front end lens battery along the light path; the first objective lens tube comprises a front lens tube close to one end of the object space and a first combined prism tube far away from one end of the object space; a through hollow cavity is arranged inside the front end lens tube, and the front end lens group is fixedly embedded in the hollow cavity of the front end lens tube; the first combined prism tube is internally provided with a through hollow cavity, and at least part of the structure of the combined prism is fixedly embedded in the hollow cavity of the first combined prism tube. The device can fix the integral structure of the objective lens of the endoscope, and the imaging quality of the objective lens device is improved.

Description

Endoscope and objective lens device

Technical Field

The utility model relates to an endoscope technical field, concretely relates to endoscope and objective device thereof.

Background

The endoscope is a detection instrument integrating optical, electronic and software technologies, enters through a natural pore canal of a human body and reaches a lesion position to be checked so as to perform real-time dynamic imaging monitoring on the lesion condition.

Endoscopes typically include an objective lens for imaging, a rod lens for transmitting image information, and an eyepiece lens for presenting the image information for viewing by a user. When the endoscope is used for detection, at least part of structures of the objective lens and the rod lens need to enter a human body, so in order to fix and protect an endoscope system, the outer surfaces of the objective lens and the rod lens are sleeved with lens tubes. At present, the lens tube is usually only sleeved on the outer surface of the rear lens of the objective lens, and the front lens is fixed on the objective lens after being glued with the rear lens. However, in this way, the front lens and the rear lens are easy to shift during gluing, which affects the imaging quality of the objective lens; meanwhile, in order to prevent the front-end lens from being separated from the rear-end lens during inspection, higher requirements are put forward on gluing, and the gluing difficulty is high.

SUMMERY OF THE UTILITY MODEL

The application provides an endoscope and objective lens device thereof, and this objective lens device can fix the overall structure of objective lens, has promoted objective lens device's imaging quality.

According to a first aspect of the present application, there is provided an objective lens apparatus comprising: the objective lens device comprises a front-end lens group and a combined prism, wherein the combined prism is arranged behind the front-end lens group along an optical path;

the first objective lens tube comprises a front lens tube close to one end of the object space and a first combined prism tube far away from one end of the object space; a through hollow cavity is arranged inside the front end lens tube, and the front end lens group is fixedly embedded in the hollow cavity of the front end lens tube; the first combined prism tube is internally provided with a through hollow cavity, and at least part of the structure of the combined prism is fixedly embedded in the hollow cavity of the first combined prism tube.

According to a specific embodiment of the present application, the objective lens apparatus further includes a first cemented lens disposed behind the combining prism along the optical path, and a second objective lens disposed behind the first objective lens along the optical path, the second objective lens includes a first cemented lens tube, a through hollow cavity is disposed inside the first cemented lens tube, and the first cemented lens is fixedly embedded in the hollow cavity of the first cemented lens tube.

According to a specific embodiment of the present application, the combined prism of the above embodiment includes at least one lens and one plano-convex lens, the second objective tube further includes a second combined prism tube, a through hollow structure is disposed inside the second combined prism tube, and the plano-convex lens is fixedly embedded in a hollow cavity of the second combined prism tube; the structure outside the plano-convex lens in the combined prism is fixedly embedded in the hollow cavity of the first combined prism tube.

According to a specific embodiment of the present application, the outer surface of the first objective lens tube and the outer side surface of the second objective lens tube in the above embodiments are cylindrical with the same radius, the first objective lens tube and the second objective lens tube are coaxially arranged, and the rear end surface of the first objective lens tube and the front end surface of the second objective lens tube are tightly attached and fixed

According to a specific embodiment of the present application, the front lens tube and the first combined prism tube in the above embodiments are of an integral structure; or the front end lens tube and the first combined prism tube are two parts which are processed separately, and the rear end surface of the front end lens tube is jointed with the front end surface of the first combined prism tube and is sealed and fixed.

According to an embodiment of the present application, the front lens tube of the objective lens device is in interference fit with the front lens group; and/or the first combining prism tube is in interference fit with at least part of the structure of the combining prism.

According to a specific embodiment of the present application, the objective lens device further includes a protective glass layer, a hollow cavity for accommodating the protective glass layer is disposed inside the front end lens tube, and the hollow cavity for accommodating the protective glass layer is located at a front end of the hollow cavity for accommodating the front end lens group.

According to an embodiment of the present application, the objective lens device further includes a spacer tube disposed between the front lens tube and the first combined prism tube

According to an embodiment of the present application, the objective lens device further includes an outer tube, and the outer tube is sleeved on an outer surface of the first objective lens tube.

According to a specific embodiment of the present application, the outer tube of the above-described embodiment is made of a biocompatible material.

According to an embodiment of the present application, the first objective tube is made of a biocompatible material.

According to a second aspect of the present application, there is provided an endoscope comprising an objective lens arrangement as described above; a rod lens device arranged behind the objective lens device along the optical path and used for transmitting the real image; and the eyepiece device is arranged behind the rod lens device along the optical path and used for presenting a real image of the measured object for a user to observe.

According to the endoscope and the objective lens device thereof of the embodiment, the device comprises the front end lens group, the combined prism and the first objective lens tube for fixing the front end lens group and the combined prism, the front end lens group and the combined prism can be accurately fixed through the first objective lens tube, and the problem of imaging quality reduction caused by lens gluing offset is effectively solved.

Drawings

FIG. 1 is a schematic configuration of an objective lens device according to an embodiment;

FIG. 2 is a schematic configuration of an objective lens device according to another embodiment;

FIG. 3 is a schematic structural diagram of a first objective lens tube and a built-in lens according to an embodiment;

FIG. 4 is a schematic structural diagram of a combining prism according to an embodiment;

FIG. 5 is a schematic diagram of a combined prism according to another embodiment;

fig. 6 is a schematic structural diagram of a first cemented mirror according to an embodiment.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings. Wherein like elements in different embodiments are numbered with like associated elements. In the following description, numerous details are set forth in order to provide a better understanding of the present application. However, those skilled in the art will readily recognize that some of the features may be omitted or replaced with other elements, materials, methods in different instances. In some instances, certain operations related to the present application have not been shown or described in detail in order to avoid obscuring the core of the present application from excessive description, and it is not necessary for those skilled in the art to describe these operations in detail, so that they may be fully understood from the description in the specification and the general knowledge in the art.

Furthermore, the features, operations, or characteristics described in the specification may be combined in any suitable manner to form various embodiments. Also, the various steps or actions in the method descriptions may be transposed or transposed in order, as will be apparent to one of ordinary skill in the art. Thus, the various sequences in the specification and drawings are for the purpose of describing certain embodiments only and are not intended to imply a required sequence unless otherwise indicated where such sequence must be followed.

The numbering of the components as such, e.g., "first", "second", etc., is used herein only to distinguish the objects as described, and does not have any sequential or technical meaning. The term "connected" and "coupled" when used in this application, unless otherwise indicated, includes both direct and indirect connections (couplings).

The embodiment of the utility model provides an in, provide an endoscope and objective device thereof, this objective device includes front end lens group and composite prism to and be used for fixing front end lens group and composite prism's first objective tube, can fix front end lens group and composite prism accurately through this first objective tube, the effectual lens veneer skew of having overcome brings the problem that the imaging quality descends, the phenomenon that simultaneously also effectual prevention front end lens broke away from objective device takes place.

In an embodiment of the present invention, an objective lens device is provided, please refer to fig. 1 and fig. 2, the objective lens device 1 includes a front lens group 11, a combination prism 12, and a first objective lens tube 210 for fixing the front lens group 11 and the combination prism 12. Wherein the combining prism 12 is disposed behind the front lens group 11 along the optical path, and the first objective lens tube 210 is sleeved on the outer surfaces of the front lens group 11 and the combining prism 12.

The front lens group 11 is used for generating a real image of the detected object, and may be composed of at least one of a spherical mirror and/or an aspherical mirror. In a preferred embodiment, the front lens group 11 comprises at least one aspherical mirror in order to better eliminate the system distortions of the objective lens arrangement. In practical applications, the front lens group 11 composed of a single aspherical mirror for imaging is difficult to process, so that an aspherical cemented mirror for imaging is formed by cementing two lenses with each other.

In an embodiment, referring to fig. 3, the aspheric cemented lens is formed by sequentially cementing a first lens 111 and a second lens 112 along the optical path, that is, the first lens 111 is a lens close to the object space, and the second lens 112 is a lens close to the combining prism 12. In this embodiment, the first lens 111 is an aspherical mirror, and a light incident surface of the aspherical mirror is a convex surface; the second lens 112 may be a spherical mirror or an aspherical mirror, and the light exit surface of the second lens may be a convex surface or a concave surface, for example: when the objective lens device 1 is an objective lens of an endoscope, the light exit surface of the second lens 112 is concave to collect light with a large field of view. In a specific embodiment, the shapes of the light exit surface of the first lens 111 and the light entrance surface of the second lens 112 may be different, and only need to satisfy the requirement that the first lens 111 and the second lens 112 are coaxially arranged after the two lenses are tightly attached and glued. In a preferred embodiment, the surfaces of the first lens 111 and the second lens 112 are flat, so as to facilitate the design and processing of the aspheric cemented lens.

In other embodiments, the front lens group 11 may also be formed by at least three lenses, and one lens close to the object space is an aspheric lens with a convex light incident surface to eliminate the distortion of the system.

The combining prism 12 is at least used for converging the light beam formed by the front end lens group 11, and the combining prism 12 at least comprises a plano-convex lens which is used for converging the light beam. In the present embodiment, the combining prism 12 further includes at least one lens for changing the viewing angle, and when the viewing angles of the objective lens device 1 are different, the shape and number of the lenses are changed accordingly.

In an embodiment of the present application, referring to fig. 4, the combining prism 12 includes a cylindrical lens 122 and a plano-convex lens 121 sequentially designed along the optical path, in this embodiment, the optical axis directions of the cylindrical lens 122 and the plano-convex lens 121 are the same, and are the central field of view, that is, the viewing angle of the objective lens device 10 is 0 °, and at this time, the light beams sequentially transmit along the optical axes of the cylindrical lens 122 and the plano-convex lens 121, corresponding to the scene where the detected object is located right in front of the objective lens device 1.

In another embodiment of the present application, referring to fig. 3 and 5, the combining prism 12 includes a complex prism set 126 and a plano-convex lens 121 sequentially designed along the optical path, wherein the complex prism set 126 is used for changing the viewing angle of the system and includes a first complex prism 123, a second complex prism 124 and a third complex prism 125. In the present embodiment, the viewing angle is θ, that is, the light is incident from an angle offset from the optical axis θ, and after passing through the first complex prism 123 and the second complex prism 124, the light is reflected by the light exit surface of the second complex prism 124 and/or the light entrance surface of the third complex prism 125, and after passing through the second complex prism 124 again, the reflected light is reflected by the light entrance surface of the second complex prism 124 and/or the light exit surface of the first complex prism 125, and finally enters the plano-convex lens 121 along the optical axis direction. In the above process, in order to ensure that the light beam is reflected on the mirror surface of the designated complex prism to change the light path, the mirror surface of the designated complex prism is coated with a reflective material, for example, in the present embodiment, the light incident surface of the third complex prism 125 and the light emergent surface of the first complex prism 125 are coated with a reflective material. It should be noted that, in the present embodiment, the light exit surface of the first complex prism 125 and the light entrance surface of the second complex prism 124 are coated with a one-way reflective material so as not to affect the transmission of the light beam in other directions. In another embodiment, the direction of the light rays can be controlled by half-coating the mirror surfaces of the designated complex prisms, since the positions of the light rays incident or reflected from the mirror surfaces of the first complex prism 123, the second complex prism 124, and the third complex prism 125 are roughly determined. For example, referring to fig. 5, the light rays are transmitted and reflected successively at different positions of the combining surface of the first complex prism 123 and the second complex prism 124, and at this time, a light reflecting material may be plated at the light ray reflecting position of the light ray emitting surface of the first complex prism 123 and/or the light ray incident surface of the second complex prism 124, so that the light rays are reflected when being incident on the position; meanwhile, no film is coated at the light transmission position, so that the light is transmitted when being emitted into the position.

In an embodiment of the present application, referring to fig. 1, the first objective lens tube 210 includes a front lens tube 211 near one end of the object space and a first combined prism tube 212 far from one end of the object space. The front end lens tube 211 is internally provided with a through hollow cavity and sleeved on the outer surface of the front end lens group 11, namely, the front end lens group 11 is fixedly embedded in the hollow cavity of the front end lens tube 211, and the front end lens tube 211 is in interference fit with the front end lens group 11 for more stably fixing the front end lens group 11. Meanwhile, a through hollow cavity is also arranged inside the first combined prism tube 212, the whole or partial structure of the combined prism 12 is fixedly embedded in the hollow cavity of the first combined prism tube 212, and the first combined prism tube 212 is in interference fit with the whole or partial structure of the combined prism 12.

In this embodiment, the portion of the structure located within the hollow cavity of first composite prism tube 212 is a complex prism assembly 126 of composite prisms 12. The front lens tube 211 and the first combined prism tube 212 may be integrally formed or may be separately formed. In the preferred embodiment, since the optical axes of the front lens group 11 and the combining prism 12 are not aligned, it is preferable that the front lens tube 211 and the first combining prism tube 212 are separately processed into two parts for convenience of installation and processing, and the rear end surface of the front lens tube 211 and the front end surface of the first combining prism tube 212 are attached and sealed and fixed. The sealing and fixing mode comprises gluing or welding and sealing.

In another embodiment, please refer to fig. 2, a portion of the structure inside the hollow cavity of the first combined prism tube 212 is the cylindrical lens 122 of the combined prism 12. At this time, it is preferable that the front lens tube 211 and the first combined prism tube 212 are integrally processed, which is more favorable for fixing the relative position relationship between the front lens group 11 and the cylindrical lens 122, and at the same time, reduces the processing difficulty of the first objective tube 210.

In some embodiments, referring to fig. 3, a first spacing tube 213 is disposed between the front lens group 11 and the combining prism 12, the first spacing tube 213 is an annular structure that is in interference fit with the front lens tube 211 and/or a portion of the inner wall of the first combining prism tube 212, and the light beam transmitted from the front lens group 11 passes through an annular gap of the first spacing tube 213 and enters the combining prism 12. In an embodiment, the first spacing tube 213 and the first objective tube 210 may be integrally formed or may be separately formed. In a preferred embodiment, the first spacing tube 213 and the first objective tube 210 are separately manufactured, and then the first spacing tube 213 is fixed to the inner wall of the first objective tube 210 by means of gluing or welding.

As can be seen from the above description, when part of the structure of the combining prism 12 is located in the first objective lens tube 210, another lens tube is also needed for fixing the rest of the combining prism 12 (i.e., the plano-convex lens 121). Therefore, in some embodiments, the objective lens device 1 further includes a second combined prism tube 221, a through hollow structure is disposed inside the second combined prism tube 221, and the plano-convex lens 121 is fixedly embedded in the hollow cavity of the second combined prism tube 221, preferably, the second combined prism tube 221 and the plano-convex lens 121 are in interference fit. The front end surface of the second combined prism tube 221 is closely attached and fixed to the rear end surface of the first objective tube 210, and the fixing mode includes gluing or welding and sealing.

In some embodiments, the objective lens arrangement 1 further comprises a first glue lens 13 arranged along the optical path after the combining prism 12. The first cemented lens 13 is cemented by lenses of at least two different materials, which is used to eliminate chromatic aberration of the optical system. In the present embodiment, the mirror surface of the first cemented mirror 13 close to the combining prism 12 and the mirror surface far from the combining prism 12 are both convex surfaces. Referring to fig. 6, in a preferred embodiment, for better chromatic aberration elimination, the first cemented lens 13 is a triple cemented lens formed by a first triple cemented lens 131, a second triple cemented lens 132 and a third triple cemented lens 133, and the three lenses are made of three different materials. In particular embodiments, the three materials used to make up the triplex mirror generally comprise at least one each of flint glass and crown glass. The radius of curvature of the three lenses is typically in the range 1.5mm to 25mm, and the glass thickness of each lens is in the range 1mm to 20 mm. The three materials are matched with different curvatures, so that color difference caused by white light refraction can be compensated, and chromatic aberration is eliminated.

Correspondingly, the objective lens device 1 further includes a first cemented lens tube 222 externally sleeved on the outer surface of the first cemented lens 13, a through hollow structure is arranged inside the first cemented lens tube 222, the first cemented lens 13 is fixedly embedded in the hollow cavity of the first cemented lens tube 222, and the preferable first cemented lens tube 222 is in interference fit with the first cemented lens 12.

In this embodiment, the second combined prism tube 221 and the first cemented prism tube 222 may be integrally formed or may be separately formed, and they jointly form the second prism tube 220. The outer surface of the second objective tube 220 and the outer surface of the first objective tube 210 are cylindrical with the same radius, the first objective tube 210 and the second objective tube 220 are coaxially arranged, and the rear end face of the first objective tube 210 and the front end face of the second objective tube 220 are tightly attached and fixed.

In some embodiments, the objective device 1 further comprises a diaphragm 14, which is transparent in the middle and opaque in the peripheral shadow, and is an aperture diaphragm for limiting the light beam. The aperture stop may be a separate stop fitting, or may be an annular structure formed by using a light-proof material on a joint surface formed in the front end lens group 11, the combining prism 12, and the first cemented lens 13. In a preferred embodiment, the aperture stop is an annular structure formed by a light-impermeable material on the mirror surface of the plano-convex lens, which simplifies the structure of the objective lens device 1. In a specific embodiment, the aperture stop may be an opaque material plated along a ring in the plane of the plano-convex lens 121; or the aperture stop is a light-tight material which is tightly attached to the plane of the plano-convex lens 121 in the combined prism 12, and the plane formed by at least one lens is plated along the ring shape, such as the light exit surface of the cylindrical lens 122 in fig. 4. In a preferred embodiment, the opaque material is chrome. When the aperture stop can be a separate stop fitting, a retaining member for fixing the stop 14 is further provided in the second objective tube 220.

In some embodiments, in order to detect the requirement of imaging, there is a second spacing 16 between the plano-convex lens 121 and the first cemented lens 13, and accordingly, the second objective tube 220 further includes a second spacing tube 223, in order to prevent the plano-convex lens 121 and the first cemented lens 13 at both ends of the second spacing 16 from sliding, in this embodiment, the inner diameter dimension of the second spacing tube 223 is smaller than the inner diameter dimensions of the second combined prism tube 221 and the first cemented lens tube 222, so as to clamp the plano-convex lens 121 in the second combined prism tube 221 and clamp the first cemented lens 13 in the first cemented lens tube 222. For example, when the inner surface of the second objective tube 220 is cylindrical, the diameter of the second spacer tube 223 is smaller than the diameters of both the second combined prism tube 221 and the first cemented prism tube 222.

In some embodiments, the objective lens device 1 further includes a protective glass layer 15, which is located at an end of the front lens group 11 close to the object space and is used for protecting the front lens group 11, and in a preferred embodiment, the protective glass layer is sapphire glass. Correspondingly, a hollow cavity for accommodating the protective glass layer 15 is arranged inside the front end lens tube 211, the preferred front end lens tube 211 is in interference fit with the protective glass layer 15, and the hollow cavity for accommodating the protective glass layer 15 is located at the front end of the hollow cavity for accommodating the front end lens group 11.

In another embodiment, the objective lens device 1 further includes an outer tube 230, the outer tube 230 is wrapped around the outer surfaces of the first objective lens tube 210 and the second objective lens tube 220, and the outer tube 230 is preferably interference-fitted with both the first objective lens tube 210 and the second objective lens tube 220.

In the above-described embodiment or embodiments not mentioned herein, outer tube 230 is made of a biocompatible material, such as metal, ceramic, synthetic polymer, natural polymer, and the like, and in the present embodiment, 304 stainless steel is preferred. Also, in a preferred embodiment, the first objective tube 210 and/or the second objective tube 220 are also made of a biocompatible material.

In another embodiment of the present invention, there is provided an endoscope apparatus including an objective lens apparatus 1, a rod lens apparatus, and an eyepiece apparatus. The objective lens device 1 is the objective lens device corresponding to fig. 1 to 6, except that in the present embodiment, in the aspheric cemented lens of the objective lens device 1, the light exit surface of the second lens 112 must be a concave surface to collect the light with a large field of view.

The rod lens device is arranged behind the objective lens device 1 along the optical path and is used for transmitting the real image formed by the objective lens device 1 to the ocular lens device. In a specific embodiment, the rod lens device may comprise a plurality of groups of cemented lenses with the same size and parameters to transfer the real image formed by the objective lens device 1 to the eyepiece lens device in a ratio of 1: 1; or, the rod lens device can also be composed of tens of thousands of extremely fine glass fibers, and the image formed by the objective lens device 1 is transmitted to the ocular lens device according to the principle of total reflection of light; in another embodiment, the rod lens device may be a micro integrated circuit sensor for converting the image information formed by the objective lens device 1 into an electrical signal and then transmitting the electrical signal to the eyepiece lens device.

The eyepiece device is used for presenting a real image of a measured object for observation by a user. In a specific embodiment, the eyepiece device may be a device disposed behind the rod lens device along the optical path for a user to observe an image of a measured object, or the eyepiece device may also be a magnifying device connected to a display device to present the image of the measured object.

In the endoscope, the outer surfaces of the rod lens unit and the eyepiece unit connected to the objective lens unit 1 are also provided with corresponding pipes which are externally fitted to the outer surfaces thereof, and the outer tube 230 may be provided separately from the pipes externally fitted to the rod lens unit and the eyepiece unit, or may be integrally formed with the pipes externally fitted to the rod lens unit and the eyepiece unit.

In the above embodiments or those not mentioned herein, the interference fit is such that, depending on the value of the interference of the shaft with the hole, a resilient pressure is generated between the surfaces of the parts after assembly, so as to obtain a tight coupling. Wherein, the interference means that the difference between the size of the hole minus the size of the matched shaft is negative. An interference fit refers to a fit having an interference (including a minimum interference equal to zero). In a specific embodiment, the shaft may be installed in the corresponding hole by using a principle of expansion and contraction with heat, or at least one of the hole and the shaft may have elasticity, and the shaft may be installed in the corresponding hole by using elastic deformation of the hole and/or the shaft.

In the above embodiments or the embodiments not mentioned herein, the manner of embedding the lens (including the front lens group 11 or the combined prism 12, etc.) into the lens tube (including the front lens tube 211 or the first combined prism tube 212, etc.) may also be other than interference fit, for example, an axial rib is provided on the inner wall of the lens tube, and a groove matched with the rib is provided on the corresponding lens to realize circumferential fixation of the lens; or a circumferential limiting structure can be arranged on the inner wall of the lens tube and is abutted against the lens, so that the lens is axially fixed.

While the principles herein have been illustrated in various embodiments, many modifications of structure, arrangement, proportions, elements, materials, and components particularly adapted to specific environments and operative requirements may be employed without departing from the principles and scope of the present disclosure. The above modifications and other changes or modifications are intended to be included within the scope of this document.

The foregoing detailed description has been described with reference to various embodiments. However, one skilled in the art will recognize that various modifications and changes may be made without departing from the scope of the present disclosure. Accordingly, the disclosure is to be considered in an illustrative and not a restrictive sense, and all such modifications are intended to be included within the scope thereof. Also, advantages, other advantages, and solutions to problems have been described above with regard to various embodiments. However, the benefits, advantages, solutions to problems, and any element(s) that may cause any element(s) to occur or become more pronounced are not to be construed as a critical, required, or essential feature or element of any or all the claims. As used herein, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, system, article, or apparatus. Furthermore, the term "coupled," and any other variation thereof, as used herein, refers to a physical connection, an electrical connection, a magnetic connection, an optical connection, a communicative connection, a functional connection, and/or any other connection.

Those skilled in the art will recognize that many changes may be made to the details of the above-described embodiments without departing from the underlying principles of the invention. Therefore, the scope of the present invention should be determined by the claims of the present invention.

Claims (10)

1. An objective lens device, characterized in that the objective lens device comprises a front lens group and a combined prism, the combined prism is arranged behind the front lens group along an optical path, the device further comprises a first objective lens tube for fixing the front lens group and the combined prism;

the first objective lens tube comprises a front lens tube close to one end of the object space and a first combined prism tube far away from one end of the object space; a through hollow cavity is arranged inside the front end lens tube, and the front end lens group is fixedly embedded in the hollow cavity of the front end lens tube; the inner part of the first combined prism tube is provided with a through hollow cavity, and at least part of structure of the combined prism is fixedly embedded in the hollow cavity of the first combined prism tube.

2. The objective lens device according to claim 1, further comprising a first cemented lens disposed along the optical path behind the combining prism, and a second cemented lens disposed along the optical path behind the first objective lens, wherein the second objective lens comprises a first cemented lens tube having a hollow cavity therethrough, and the first cemented lens is fixedly embedded in the hollow cavity of the first cemented lens tube.

3. The objective lens device according to claim 2, wherein the combination prism comprises at least one lens and a plano-convex lens, the second objective tube further comprises a second combination prism tube, the second combination prism tube has a hollow structure formed therein, and the plano-convex lens is fixedly embedded in the hollow cavity of the second combination prism tube; structures except the plano-convex lens in the combined prism are fixedly embedded in the hollow cavity of the first combined prism tube.

4. The objective lens device according to claim 2, wherein the outer surface of the first objective tube and the outer surface of the second objective tube are cylindrical with the same radius, the first objective tube and the second objective tube are coaxially arranged, and the rear end surface of the first objective tube and the front end surface of the second objective tube are closely attached and fixed.

5. The objective lens device according to any one of claims 1 to 4, wherein the front lens tube and the first combined prism tube are of an integral structure; or the front end lens tube and the first combined prism tube are two parts which are processed separately, and the rear end surface of the front end lens tube is jointed with the front end surface of the first combined prism tube.

6. The objective lens device according to claim 1, wherein the front end lens tube is interference-fitted with the front end lens group; and/or the first combining prism tube is in interference fit with at least part of the structure of the combining prism.

7. The objective lens device according to claim 1, further comprising a protective glass layer, wherein a hollow cavity for accommodating the protective glass layer is provided inside the front lens tube, and the hollow cavity for accommodating the protective glass layer is located at a front end of the hollow cavity for accommodating the front lens group.

8. The objective lens device according to claim 1, further comprising a spacer tube disposed between the front lens tube and the first combining prism tube.

9. The objective lens apparatus according to claim 1, further comprising an outer tube which is fitted over an outer surface of the first objective lens tube.

10. An endoscope, comprising:

an objective lens arrangement as claimed in any one of claims 1-9;

a rod lens device arranged behind the objective lens device along an optical path and used for transmitting a real image;

and the eyepiece device is arranged behind the rod lens device along a light path and used for presenting a real image of the measured target.