Ultrahigh-temperature-resistant endoscope probe structure

Abstract

The invention provides an ultrahigh-temperature-resistant endoscope probe structure, which relates to the technical field of endoscope probes and comprises an endoscope probe body, the endoscope probe body comprises a lens, an objective lens and an outer layer, the lens and the objective lens are integrally formed by titanium alloy, an optical fiber is arranged at the right end of the outer layer, and the objective lens is composed of three single lenses which are separated from each other in positive and negative directions. Through the structural design that the outer layer is of a circular structure and the inner layer is of an oval structure, the reasonable structural design not only ensures the high-temperature resistance and the optical performance of the probe, but also enables the probe to be small in size and convenient to carry, and according to the scheme, the assembly part of the optical module and the lens module is bonded through graphite conductive adhesive which is resistant to the high temperature of 500 DEG C; the graphite conductive adhesive is a single-component heating curing type inorganic conductive adhesive and is formed by polymerizing graphite powder serving as a conductive material and an inorganic aluminosilicate material, a cured product is black, the conductive performance is excellent, the graphite conductive adhesive can resist the high temperature of 500 DEG C, and the graphite conductive adhesive can be used at the high temperature of 1000 DEG C under the protection of inert gas.

Description

Technical Field

[0001] The present invention belongs to the technical field of endoscope probes, and more specifically, relates to an ultra-high temperature resistant endoscope probe structure. Background Art

[0002] Industrial endoscopes are mainly used in automobiles, aircraft engines, pipelines, mechanical parts, etc. They can be used for internal inspection of large mechanical equipment, as well as some places that cannot be directly observed by the human eye due to high temperature, toxicity, nuclear radiation or too small environment. Non-destructive testing can be achieved without disassembling or destroying the assembly and stopping the equipment, so as to effectively avoid the adverse effects of direct observation on the observer. For some high-temperature objects, such as running engines, burning boilers and other scenes, high-temperature resistant industrial endoscopes are required.

[0003] At present, many industrial endoscope manufacturers are unable to break through the problem of using industrial endoscopes for inspection under high temperature conditions. A cooling device needs to be installed so that the industrial endoscope can work at higher temperatures. Generally, engines reach very high temperatures during operation. For example, the operating temperature of a steam turbine engine can reach 500°C, and the cylinder temperature of a piston engine at the end of compression can reach 300°C-500°C.

[0004] However, the above-mentioned embodiments still have the following problems: in terms of high temperature resistance, even if ordinary endoscopes add cooling devices or partially replace materials, it is difficult to meet the detection requirements of ultra-high temperature environments; in terms of probe size, many designs cannot achieve small apertures, which is not conducive to detection in a small space; in terms of structural stability, some designs may have problems such as loosening or deformation of components at high temperatures, affecting the accuracy of the detection results. In response to this problem, this application proposes a solution to design an ultra-high temperature resistant endoscope probe structure, which has the advantages of high temperature resistance, small aperture, and stable structure. In addition, the optical imaging module plans to adopt an optical fiber to transmit light signals, which can meet the detection needs in ultra-high temperature environments while ensuring the accuracy of the detection results.

[0005] In view of this, the existing structure and defects are studied and improved, and an ultra-high temperature resistant endoscope probe structure is provided to achieve a more practical purpose. Summary of the Invention

[0006] In order to solve the above technical problems, the present invention provides an ultra-high temperature resistant endoscope probe structure to solve the above problems.

[0007] A super-high temperature resistant endoscope probe structure includes an endoscope probe body, the endoscope probe body includes a lens, an objective lens and an outer layer, the lens and objective lens are made of titanium alloy as a whole, an optical fiber is provided at the right end of the outer layer, the objective lens is composed of three single lenses with positive and negative separations, the optical fiber is composed of a core, a cladding and a coating layer, the positive lens in the single lens is made of high-refractive index and low-dispersion glass, and the negative lens is made of low-refractive index and high-dispersion glass, an optical fiber bundle, an eyepiece and a camera are provided on the right side of the objective lens, the outer layer is a circular structure, and the inner layer is an elliptical structural design, the objective lens and the titanium alloy one-piece lens are cross-cut into and then the lens of the objective lens is rotated to fix it to the titanium alloy inner layer.

[0008] Preferably, the coating material of the optical fiber is a gold-plated coating, which makes it have excellent corrosion resistance. The connection between the optical fiber and the lens is achieved by punching and welding. The lens is made of sapphire glass, which can withstand high temperatures of 1800°C. The objective lens adopts a Kirk three-piece type, and its material is a flint glass lens and a lanthanum crown glass lens.

[0009] Preferably, the lens and objective lens are respectively fixed on the outer layer, the optical fiber is a glass fiber material, which can transmit light signals by using the principle of total reflection of light, the objective lens transmits the object surface light signal to the optical fiber bundle, and the optical fiber bundle then transmits the light signal to the eyepiece outside the working pipe, and then transmits it to the camera for image display and data processing.

[0010] Preferably, both ends of the objective lens are coated with graphite conductive glue that is resistant to high temperatures of 500° C., and the lens is located at the front end, so that the external scene is imaged on the photosensitive surface of the image sensor.

[0011] Compared with the prior art, the present invention has the following beneficial effects: In the present invention, the outer layer is a circular structure and the inner layer is an elliptical structural design. This reasonable structural design not only ensures the high temperature resistance and optical performance of the probe, but also makes the probe compact and easy to carry. This solution uses a high temperature resistant graphite conductive adhesive of 500°C for bonding in the assembly part of the optical module and the lens module. A528 graphite conductive adhesive is a single-component heat-curing inorganic conductive adhesive. It is polymerized with graphite powder as the conductive material and inorganic aluminosilicate material. The cured product is black and has excellent conductive properties. It can withstand high temperatures of 500°C and can be used at high temperatures of 1000°C under inert gas protection.

[0012] In the present invention, a coating layer is added to the periphery of all optical fibers. After being transmitted through the optical fibers, the light signal is conducted to the outside of the pipe, and then sent to the photosensitive surface of the camera after passing through the eyepiece. The lens is located at the front end, so that the external scene is imaged on the photosensitive surface of the image sensor. In order to adapt to the different sizes of the camera photosensitive surfaces, the eyepiece can be replaced. This solution avoids the image distortion caused by the inability to adapt to the high temperature environment of 500°C when the camera is directly placed in the pipe for detection. The use of high-temperature resistant materials fundamentally guarantees the structural stability and functionality of the probe in high-temperature environments.

[0013] In the present invention, the coating material of the optical fiber adopts a gold-plated coating, which gives it excellent corrosion resistance and enables the optical fiber to reach a temperature range of -269°C to 700°C. The outer layer and the coating layer are bonded with graphite conductive adhesive, which can make them tightly combined. It has the advantages of high temperature resistance, wear resistance, oil resistance, and corrosion resistance. Combined with the high-temperature protective layer of this solution, high-temperature working conditions of 500°C can be easily achieved.

[0014] In the present invention, the optical imaging module intends to adopt a structural design of optical fiber transmission of light signals. By rationally designing the arrangement and structure of the optical fibers, at least 12×12 optical fibers are arranged within a diameter range of 3mm to meet the size requirement of the probe with a diameter of 4mm, thereby achieving the advantage of a small aperture of only 4mm. This small aperture design is conducive to the probe to perform detection in a small space, and can enter some areas that are difficult to reach with ordinary endoscopes, thereby improving the flexibility and accuracy of detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the overall structure of the present invention; Figure 2 2 is a schematic diagram of the imaging structure of the objective lens of the present invention; Figure 3 This is a schematic diagram of the lens assembly structure of the present invention; Figure 4 Schematic diagram of the structure of the optical imaging module of the present invention; Figure 5 It is a schematic diagram of the structure of the Kirk three-piece objective lens of the present invention; Figure 6 It is a schematic diagram of the end face structure of the optical fiber bundle of the present invention.

[0016] In the figure, the correspondence between the structure names and the drawing numbers is: 1. Endoscope probe body; 2. Lens; 3. Single lens; 4. Optical fiber; 5. Objective lens; 6. Optical fiber bundle; 7. Eyepiece; 8. Camera; 9. Coating layer; 10. Cladding; 11. Outer layer; 12. Fiber core. DETAILED DESCRIPTION

[0017] The following embodiments of the present invention are described in further detail with reference to the accompanying drawings and examples. The following examples are used to illustrate the present invention but are not intended to limit the scope of the present invention.

[0018] See also Figure 1 - Figure 6 The present invention provides an ultra-high temperature resistant endoscope probe structure, including an endoscope probe body 1, the endoscope probe body 1 includes a lens 2, an objective lens 5 and an outer layer 11, the lens 2 and the objective lens 5 are made of titanium alloy integrally formed, an optical fiber 4 is provided at the right end of the outer layer 11, the objective lens 5 is composed of three single lenses 3 separated by positive and negative, the optical fiber 4 is composed of a core 12, a cladding 10 and a coating layer 9, the positive lens in the single lens 3 is made of high refractive index and low dispersion glass, and the negative lens is made of low refractive index and high dispersion glass, an optical fiber bundle 6, an eyepiece 7 and a camera 8 are provided on the right side of the objective lens 5, the outer layer 11 is a circular structure, and the inner layer is an elliptical structure design, the objective lens 5 and the titanium alloy integrally formed lens 2 cross-cut into the rear rotating objective lens 5 The sheet is fixed to the inner layer of titanium alloy. In this solution, high-temperature resistant materials and sealing structures are used in the endoscope probe module. The outer layer 11 is a circular structure and the inner layer is an elliptical structural design. This reasonable structural design not only ensures the high-temperature resistance and optical performance of the probe, but also makes the probe compact and easy to carry. In this solution, high-temperature resistant 500°C graphite conductive adhesive is used for bonding the assembly of the optical module and the lens 2 module. A528 graphite conductive adhesive is a single-component heat-curing inorganic conductive adhesive. It is made of graphite powder as the conductive material and an inorganic aluminosilicate material. The cured product is black and has excellent conductive properties. It can withstand high temperatures of 500°C and can be used at high temperatures of 1000°C under inert gas protection.

[0019] The coating material of optical fiber 4 is gold-plated, which makes it have excellent corrosion resistance. The connection between optical fiber 4 and lens 2 is achieved by punching and welding. Lens 2 is made of sapphire glass, which can withstand high temperatures of 1800°C. Objective lens 5 adopts a Kirk triplet, which is made of flint glass lens and lanthanum crown glass lens. This solution intends to use optical fiber 4 to transmit light signals in the optical imaging module. The light signal containing image information obtained by lens 2 is transmitted to the CMOS module via optical fiber 4. Optical fiber 4 is a glass fiber material that can transmit light signals based on the principle of total reflection of light. Compared with the spatial optical path structure, the optical fiber 4 can be bent within a certain angle range without affecting the transmission quality of the optical signal. The common operating temperature of the optical fiber 4 is -40°C to 70°C. The coating material of the optical fiber 4 adopts a gold-plated coating, which makes it have excellent corrosion resistance, so that the temperature range that the optical fiber 4 can reach is -269°C to 700°C. The outer layer 11 and the coating layer 9 are bonded with graphite conductive glue, which can make them tightly combined. It has the advantages of high temperature resistance, wear resistance, oil resistance, and corrosion resistance. Combined with the high-temperature protective layer of this solution, high-temperature working conditions of 500°C can be easily achieved.

[0020] The lens 2 and the objective lens 5 are fixed on the outer layer 11 respectively. The optical fiber 4 is a glass fiber material that can transmit light signals based on the principle of total reflection of light. The objective lens 5 transmits the object surface light signal to the optical fiber bundle 6, and the optical fiber bundle 6 then transmits the light signal to the eyepiece 7 outside the working pipe, and then transmits it to the camera 8 for image display and data processing. The optical fiber 4 is composed of a core 12, a cladding 10 and a coating 9. The diameter of the core 12 of the optical fiber 4 that transmits visible light is usually around 4μm, the cladding 10 is usually a core of 125μm, and the coating 9 is 245μm. This scheme proposes to use a high-density optical fiber bundle 6 to receive the light signal refracted by the lens 2. It is expected that at least 12×12 optical fibers 4 will be arranged within a diameter range of 3mm to meet the size requirement of the probe with a diameter of 4mm. Reasonable selection or design of the optical lens 2 is the key to ensuring clear imaging. The main parameters of the lens 2 are not the same. The appropriate parameter indicators should be determined according to different interfaces, image sensor optical formats, aperture, field of view, focal length, etc. The field of view angle is very important in optical work. The field of view is also called the field of view. The size of the field of view angle determines the field of view of the optical instrument. The larger the viewing angle, the wider the field of view. In the design of the imaging optical path module, this solution intends to achieve a 60-degree field of view angle. The image size is controlled within a diameter of 3mm so that the optical fiber bundle 6 can receive it. In this solution, it is intended to achieve a 60-degree field of view angle. The best focusing position, that is, the object distance, is about 50mm. The image height is the radius of the optical fiber bundle 6, that is, 1.5mm. According to the lens imaging formula, the equivalent focal length of the objective lens 5 is 2.4mm. Under the same brightness In this environment, the smaller the aperture of the lens 2, the brighter the image. Considering the usage scenario of this project, the lens 2 with an F value of 5 is proposed, so the depth of field is about 10mm to infinity. The photographic objective 5 belongs to a large field of view system, and various aberrations need to be fully corrected to obtain a clear image. The accuracy of this solution must reach 10μm, and an image resolution of less than 10μm can be considered an acceptable ideal structure. Combined with the 60-degree field of view and F value proposed in this solution, the Kirk three-piece objective 5 structure is proposed to correct the aberrations.

[0021] Both ends of the objective lens 5 are coated with graphite conductive glue that is resistant to high temperatures of 500°C. The lens 2 is located at the front end, so that the external scene is imaged on the photosensitive surface of the image sensor. The objective lens 5 is composed of three single lenses 3 separated into positive and negative parts, with a total of eight variables. It is the simplest structure that can correct seven aberrations at the same time, and is also the structure widely used in current popular cameras 8. The positive lens in the single lens 3 adopts high-refractive-index low-dispersion glass, and the negative lens adopts low-refractive-index high-dispersion glass. In the design of the objective lens 5 of this scheme, the positive lens adopts high-refractive-index low-dispersion glass, and the negative lens adopts low-refractive-index high-dispersion glass. After appropriate improvements, it is expected that the aberration correction under the conditions of 60-degree field of view and 1 / 5 relative aperture can be achieved to meet the accuracy requirements. The imaging light signals of different areas after passing through the objective lens 5 enter the optical fibers 4 at different positions respectively. In order to save space In this scheme, more optical fibers 4 are inserted within a 3mm diameter. This scheme proposes to remove the coating 9 of each optical fiber 4 and then arrange them in combination. Therefore, the diameter of each optical fiber 4 can be controlled at about 125μm of the fiber core. In order to ensure that the optical fiber bundle 6 has a certain bending ability, a coating layer 9 is added to the periphery of all optical fibers 4. After the light signal is transmitted through the optical fiber 4, it is transmitted to the outside of the pipe and sent to the photosensitive surface of the camera 8 after passing through the eyepiece 7. The lens 2 is located at the front end, so that the external scene is imaged on the photosensitive surface of the image sensor. In order to adapt to the different sizes of the photosensitive surface of the camera 8, the eyepiece 7 can be replaced. This scheme avoids the problem that when the camera 8 is directly placed in the pipe for detection, it cannot adapt to the high temperature environment of 500℃ and cause image distortion. The use of high-temperature resistant materials fundamentally guarantees the structural stability and functionality of the probe in a high-temperature environment.

[0022] Working principle: In the first step, this solution uses high-temperature resistant materials and sealing structures in the endoscope probe module. The outer layer 11 is a circular structure and the inner layer is an elliptical structural design. This reasonable structural design not only ensures the high-temperature resistance and optical performance of the probe, but also makes the probe compact and easy to carry. This solution uses high-temperature resistant 500°C graphite conductive adhesive to bond the assembly of the optical module and the lens 2 module. A528 graphite conductive adhesive is a single-component heat-curing inorganic conductive adhesive. It is made of graphite powder as the conductive material and inorganic aluminosilicate material. The cured product is black and has excellent conductive properties. It can withstand high temperatures of 500°C and can be used at high temperatures of 1000°C under inert gas protection. This solution intends to use optical fiber 4 to transmit light signals in the optical imaging module. The optical signal containing image information obtained by the lens 2 is transmitted to the CMOS module via the optical fiber 4. The optical fiber 4 is a glass fiber material that can transmit optical signals by utilizing the principle of total reflection of light. Compared with the spatial optical path structure, the optical fiber 4 can be bent within a certain angle range without affecting the transmission quality of the optical signal. The common operating temperature of the optical fiber 4 is -40°C to 70°C. The coating material of the optical fiber 4 adopts a gold-plated coating, which makes it have excellent corrosion resistance, so that the temperature range that the optical fiber 4 can reach is -269°C to 700°C. The outer layer 11 and the coating layer 9 are bonded together with graphite conductive adhesive, so that they can be tightly combined. It has the advantages of high temperature resistance, wear resistance, oil resistance, and corrosion resistance. Combined with the high-temperature protective layer of this solution, high-temperature working conditions of 500°C can be easily achieved.

[0023] In the second step, the optical fiber 4 is composed of a core 12, a cladding 10 and a coating 9. The diameter of the core 12 of the optical fiber 4 that transmits visible light is usually around 4 μm, the cladding 10 is usually a core 125 μm, and the coating 9 is 245 μm. This solution proposes to use a high-density optical fiber bundle 6 to receive the light signal refracted by the lens 2. It is expected that at least 12×12 optical fibers 4 will be arranged within a 3 mm diameter range to meet the size requirement of the probe 4 mm diameter. Reasonable selection or design of the optical lens 2 is the key to ensuring clear imaging. The main parameters of the lens 2 are not the same. Appropriate parameter indicators should be determined according to different interfaces, image sensor optical formats, apertures, fields of view, focal lengths, etc. The field of view angle is also called the field of view in optical engineering. The size of the field of view angle determines the field of view of the optical instrument. The larger the viewing angle, the wider the field of view. In the design of the imaging optical path module, this solution is intended to implement The current field of view is 60 degrees, and the image size is controlled within a diameter of 3mm so that the optical fiber bundle 6 can receive it. In this scheme, a field of view of 60 degrees is intended to be achieved, and the optimal focusing position, that is, the object distance, is about 50mm. The image height is the radius of the optical fiber bundle 6, that is, 1.5mm. According to the lens imaging formula, it can be calculated that the equivalent focal length of the objective lens 5 is 2.4mm. Under the same bright environment, using a lens 2 with a small aperture, the brighter the image. Considering the usage scenarios of this project, a lens 2 with an F value of 5 is intended to be selected, so the depth of field is about 10mm to infinity. The photographic objective lens 5 belongs to a large field of view system and needs to be fully corrected for various aberrations to obtain a clear image. The accuracy of this scheme must reach 10μm, and an image resolution of less than 10μm can be considered an acceptable ideal structure. Combined with the 60-degree field of view and F value proposed in this scheme, the Kirk three-piece objective lens 5 structure is intended to correct the aberrations.

[0024] In the third step, the objective lens 5 is composed of three single lenses 3 separated into positive and negative parts, with a total of eight variables. It is the simplest structure that can correct seven aberrations at the same time, and is also the structure widely used in current popular cameras 8. The positive lens in the single lens 3 adopts high-refractive-index and low-dispersion glass, and the negative lens adopts low-refractive-index and high-dispersion glass. In the design of the objective lens 5, the positive lens adopts high-refractive-index and low-dispersion glass, and the negative lens adopts low-refractive-index and high-dispersion glass. After appropriate improvements, it is expected to achieve aberration correction for 60-degree field of view and 1 / 5 relative aperture to meet precision requirements. The imaging light signals of different areas after passing through the objective lens 5 enter the optical fibers 4 at different positions respectively. In order to save space, more optical fibers 4 are inserted within a diameter of 3mm. This scheme intends to The coating layers 9 of the optical fibers 4 are removed and then recombined and arranged, so the diameter of each optical fiber 4 can be controlled at about 125μm of the fiber core. In order to ensure that the optical fiber bundle 6 has a certain bending ability, a coating layer 9 is added to the periphery of all optical fibers 4. After the light signal is transmitted through the optical fiber 4, it is transmitted to the outside of the pipeline, and then sent to the photosensitive surface of the camera 8 after passing through the eyepiece 7. The lens 2 is located at the front end, so that the external scene is imaged on the photosensitive surface of the image sensor. In order to adapt to the different sizes of the photosensitive surfaces of the camera 8, the eyepiece 7 can be replaced. This solution avoids the problem of image distortion caused by the camera 8 being unable to adapt to the high temperature environment of 500℃ when it is directly placed in the pipeline for detection. The use of high-temperature resistant materials fundamentally guarantees the structural stability and functionality of the probe in a high-temperature environment.

[0025] The examples of the present invention are presented for purposes of illustration and description and are not intended to be exhaustive or to limit the invention to the disclosed forms. Many modifications and variations will be apparent to those skilled in the art. The embodiments are chosen and described in order to better illustrate the principles of the invention and its practical application and to enable those skilled in the art to understand the invention and design various embodiments with various modifications as are suited for specific applications.

Claims

1. An ultra-high temperature resistant endoscope probe structure, comprising an endoscope probe body (1), characterized in that: The endoscope probe body (1) comprises a lens (2), an objective lens (5) and an outer layer (11); the lens (2) and the objective lens (5) are integrally formed of titanium alloy; an optical fiber (4) is provided at the right end of the outer layer (11); and the objective lens (5) is composed of three single lenses (3) with positive and negative separations; The optical fiber (4) is composed of a core (12), a cladding (10) and a coating layer (9); the positive lens in the single lens (3) is made of high-refractive-index, low-dispersion glass, and the negative lens is made of low-refractive-index, high-dispersion glass; an optical fiber bundle (6), an eyepiece (7) and a camera (8) are arranged on the right side of the objective lens (5); the outer layer (11) is a circular structure, and the inner layer is an elliptical structural design.

2. The ultra-high temperature resistant endoscope probe structure according to claim 1, characterized in that: The coating material of the optical fiber (4) is a gold-plated coating.

3. The ultra-high temperature resistant endoscope probe structure according to claim 1, characterized in that: The optical fiber (4) and the lens (2) are connected by punching and welding, and the lens (2) is made of sapphire glass.

4. The ultra-high temperature resistant endoscope probe structure according to claim 1, characterized in that: The objective lens (5) is a Kirk three-piece lens, and its material is a flint glass lens and a lanthanum crown glass lens.

5. The ultra-high temperature resistant endoscope probe structure according to claim 1, characterized in that: The lens (2) and the objective lens (5) are respectively fixed on the outer layer (11).

6. The ultra-high temperature resistant endoscope probe structure according to claim 1, characterized in that: The optical fiber (4) is made of glass fiber material.

7. The ultra-high temperature resistant endoscope probe structure according to claim 1, characterized in that: Both ends of the objective lens (5) are coated with graphite conductive glue that is resistant to high temperatures of 500°C.

8. The ultra-high temperature resistant endoscope probe structure according to claim 1, characterized in that: The lens (2) is located at the front end.

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