Light guide structure, endoscope front end and manufacturing method of light guide structure

Abstract

A light guide structure for use in an endoscope to guide light along a length direction includes a first portion and a second portion. The first portion extends along the length direction with a single cross-section. The second portion extends along the length direction with a varying cross-section and connects to one end of the first portion along the length direction. An endoscope front end includes a circuit board, an image capturing assembly, and the light guide structure. The light guide structure matches the contours of the circuit board and the image capturing assembly to increase space utilization and obtain a larger cross-sectional area. Regarding the fabrication of the light guide structure, the second portion is formed by shaping a portion extending directly from the end of the first portion, or by molding additional material directly bonded to the end of the first portion using a mold. An endoscope front end and a method for manufacturing a light guide structure for use within an endoscope are also proposed.

Description

Technical Field

[0001] This invention relates to a light guide structure, and more particularly to a light guide structure for an endoscope and a method for manufacturing the light guide structure. Background Technology

[0002] A typical endoscope mainly consists of a control handle and a long insertion tube connected to the control handle. Multiple channels are formed within the insertion tube to allow the passage of desired items, such as wires, optical fibers, bending control cables, instruments, etc. One end of the insertion tube usually has an image capture device. The light required to capture the image is generated by an external light source and travels through the optical fiber to the end to illuminate the object being photographed. The user can bend the insertion tube, capture images, operate instruments, etc., by holding and manipulating the control handle. Generally, to provide sufficient light intensity when capturing images, the optical fiber (or fiber bundle) needs to have a certain outer diameter. Furthermore, considering the attenuation of light transmission, the diameter of the optical fiber (or fiber bundle) also needs to increase with the length of the insertion tube. The outer diameter of longer insertion tubes is difficult to reduce, which limits the range of applications. In addition, longer optical fibers are more expensive to manufacture, and the extension connections between fibers also increase attenuation. Summary of the Invention

[0003] In view of the problems in the prior art, one object of the present invention is to provide a light guiding structure that can replace conventional optical fibers in endoscopes, thereby reducing the insertion diameter of the endoscope.

[0004] A light guide structure according to the present invention is used in an endoscope to guide light along a length direction. The light guide structure includes a first portion and a second portion. The first portion extends along the length direction with a single cross-section. The second portion extends along the length direction with a varying cross-section and is connected to one end of the first portion along the length direction. The second portion is formed either by shaping a portion extending directly from the end of the first portion or by molding additional material directly bonded to the end of the first portion using a mold. Thus, the second portion can be formed according to the structural configuration of the end-tube end of the endoscope in which the light guide structure is disposed. Because the light source can be positioned relatively close to the end-tube end, the outer diameter of the endoscope's insertion tube can be reduced. The light emitted by the light source is guided by the light guide structure to smoothly exit from the end-tube end. Furthermore, the path length of the light through the light guide structure is shorter than the path length through the optical fiber in a conventional endoscope, resulting in lower light transmission attenuation and lower power of the light source.

[0005] Another object of the present invention is to provide an endoscope front end equipped with a light guide structure. This light guide structure can replace traditional optical fibers, thereby reducing the insertion diameter of the endoscope equipped with the light guide structure.

[0006] An endoscope front end according to one invention includes a circuit board, an image capturing component, a light-emitting component, and a light guide structure as described above. The image capturing component and the light-emitting component are disposed on the circuit board. The light guide structure is disposed on the circuit board to guide the light emitted by the light-emitting component along a length direction. Thus, the second portion can be formed according to the structural configuration of the endoscope front end (including the circuit board, the image capturing component, and other components or, for example, the arrangement of channels for instrument use). The outer diameter of the insertion tube of the endoscope with the endoscope front end disposed is reduced. The light emitted by the light-emitting component is guided by the light guide structure to smoothly exit from the endoscope front end. Furthermore, the path length of the light through the light guide structure is shorter than the path length through the optical fiber in a conventional endoscope, resulting in lower light transmission attenuation and lower power of the light-emitting component.

[0007] Another object of the present invention is to provide a method for manufacturing a light guide structure for use within an endoscope. This method uses a two-stage molding process to fabricate the light guide structure, which increases the structural adaptability of the light guide structure.

[0008] According to one embodiment of the present invention, a method for manufacturing a light guide structure for use within an endoscope includes the steps of: (a) providing a light-transmitting structure extending along a length direction with a single cross-section and having a first end and a second end in the length direction opposite to the first end; and (b) shaping a portion of the light-transmitting structure having the second end such that the shaped portion extends along the length direction with a varying cross-section, thereby completing the light guide structure. Wherein, the second portion can be shaped as needed, without being limited by the structure of the first portion, thereby increasing the overall structural adaptability of the light guide structure. In principle, the light guide structure can replace conventional optical fibers and be used in endoscopes or endoscope tips, thereby reducing the insertion diameter of the endoscope or an endoscope with the endoscope tip.

[0009] According to another embodiment of the present invention, a method for manufacturing a light guide structure for use in an endoscope includes the steps of: (a) providing a light-transmitting structure extending along a length direction with a single cross-section and having a first end and a second end in the length direction opposite to the first end; (b) providing a mold having a cavity; (c) disposing the light-transmitting structure in the mold such that the second end is exposed within the cavity; (d) filling the cavity with a material; and (e) curing the material within the cavity such that the cured material is directly bonded to the second end and extends along the length direction with a varying cross-section, thereby completing the light guide structure. Herein, the second portion can be shaped as needed (e.g., by designing the size of the cavity) without being limited by the structure of the first portion, thus increasing the overall structural adaptability of the light guide structure. In principle, this light guide structure can replace traditional optical fibers and be used in endoscopes or endoscope tips, thereby reducing the insertion diameter of the endoscope or an endoscope with the endoscope tip.

[0010] The advantages and spirit of this invention can be further understood from the following detailed description of the invention and the accompanying drawings. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of an endoscope according to one embodiment.

[0012] Figure 2 for Figure 1 A schematic diagram of the front end of one of the endoscopes.

[0013] Figure 3 for Figure 2 Exploded view of the front end of the central endoscope.

[0014] Figure 4 for Figure 3 A schematic diagram of one of the light guide structures at the front end of the endoscope.

[0015] Figure 5 for Figure 3 A cross-sectional view of the central light-guiding structure along its length; other surrounding structures are shown in dashed lines.

[0016] Figure 6 for Figure 4 Cross-sectional view of the central optical guide structure along line XX.

[0017] Figure 7 for Figure 4 Cross-sectional view of the central optical guide structure along line YY.

[0018] Figure 8 This is a cross-sectional view of the front end of an endoscope, without a third part, including the light guide structure, circuit board, and light-emitting components.

[0019] Figure 9 This is a cross-sectional view of the front end of an endoscope, without a third part, including the light guide structure, circuit board, and light-emitting components.

[0020] Figure 10 A flowchart illustrating the method for manufacturing a light guide structure.

[0021] Figure 11 This is a schematic diagram of a light-transmitting structure and a mold used to shape the light-transmitting structure.

[0022] Figure 12 for Figure 11 A schematic diagram of a light-transmitting structure shaped to have a second part.

[0023] Figure 13 for Figure 12 A schematic diagram of a centrally translucent structure further shaped to have a third part.

[0024] Figure 14 This is a schematic diagram of a light-transmitting structure shaped to have a light-incident surface that is inclined relative to the length direction, based on an example.

[0025] Figure 15 This is a flowchart of another method for manufacturing light guide structures.

[0026] Figure 16 This is a schematic diagram of a light-transmitting structure and a mold for forming a second part that is directly connected to the light-transmitting structure. Detailed Implementation

[0027] Please see Figures 1 to 5 According to one embodiment of the present invention, an endoscope 1 includes a control handle 12 and an insertion tube 14. The insertion tube 14 has a plurality of channels for the passage of desired objects, such as wires, bending control cables, instruments, water, or other liquids; these are not shown in the figures for simplicity. The insertion tube 14 has an endoscope tip 16 at one end and is connected to the control handle 12 via the other end. The user can hold and operate the control handle 12 to control the direction of the endoscope tip 16, operate instruments, etc.

[0028] In this embodiment, the endoscope tip 16 includes a front housing 160, a circuit board 162, an image capturing assembly 164, a light-emitting assembly 166, and a light guide structure 168. The front housing 160 (shown as a thin tube for simplification) houses the circuit board 162, the image capturing assembly 164, the light-emitting assembly 166, and the light guide structure 168. The circuit board 162 is electrically connected to a control handle 12 (e.g., via a wire passing through the channel), enabling the control handle 12 to provide power to the circuit board 162 and control its operation. In principle, the channel also extends to the front housing 160, allowing the instrument to extend out of the endoscope tip 16. For example, the front housing 160 may be directly formed or incorporated with other inserts to form part of the channel. The image capturing assembly 164 is disposed on the circuit board 162 and protrudes from one end of the front housing 160 (or the tip of the endoscope tip 16), allowing the image capturing assembly 164 to be controlled to capture images in front of the endoscope tip 16. The light-emitting component 166 is disposed on the circuit board 162 to provide the light required for the image capturing component 164 to capture images. The light guide structure 168 is disposed above the circuit board 162 and between the image capturing component 164 and the light-emitting component 166, and is used to guide the light emitted by the light-emitting component 166 along a length direction 168a (indicated by a double arrow in the figure) to illuminate the front end 16 of the endoscope.

[0029] In this embodiment, the light guide structure 168 includes a first portion 1682, a second portion 1684, and a third portion 1686. The first portion 1682 extends along its length 168a with a single cross-section. This cross-section can be designed to match its surrounding structures, such as the circuit board 162 and / or the front housing 160, so that the first portion 1682 does not structurally interfere with them. In this embodiment, the cross-section of this first portion 1682 (shown as the shaded area in Figure 4) is an arc segment with a central angle greater than 180 degrees and conforms to the contour of the circuit board 162. However, this is not a limitation in practice.

[0030] The second portion 1684 is connected to one end 1682a of the first portion 1682 in the length direction 168a; in other words, the first portion 1682 is closer to the light-emitting component 166 relative to the second portion 1684. The second portion 1684 extends along the length direction 168a with a varying cross-section. Similarly, the cross-section of this second portion 1684 can be designed to match its surrounding structures, such as the image capturing component 164 and / or the front-end housing 160, so that the second portion 1684 does not cause structural interference with them. In this embodiment, as... Figure 6 As shown, the outer side of the cross-section of the second part 1684, which is relatively close to the first part 1682, is arc-shaped (with a central angle greater than 180 degrees); the inner side of the cross-section is n-shaped to avoid structural interference with the upwardly extending circuit board 162. Figure 7 As shown, the cross-section of the second portion 1684, which is relatively far from the first portion 1682, is an arc-shaped thin shell to conform to the contours of the front housing 160 and the image capturing component 164. Furthermore, the second portion 1684 has a component receiving space 1684a. The image capturing component 164 is at least partially received within the component receiving space 1684a. In practice, the changing cross-section of the second portion 1684 is not limited to a continuously changing situation. The trend of the change in the cross-section of the second portion 1684 along the length direction 168a is, in principle, determined by its surrounding structure. Additionally, for example, the second portion 1684 can be formed by shaping a portion extending directly from the end 1682a of the first portion 1682 (i.e., the first and second portions are a single component made of the same material), or it can be formed by molding additional material directly bonded to the end 1682a of the first portion 1682. In this way, the second part 1684 can be molded as needed (e.g., by designing a mold for molding), without being limited by the structure of the first part 1682, thereby increasing the overall structural adaptability of the light guide structure 168.

[0031] Please return Figures 3 to 5 The third portion 1686 connects to the other end 1682b of the first portion 1682 relative to the second portion 1684, and extends along the length direction 168a with a varying cross-section. The third portion 1686 is located between the first portion 1682 and the light-emitting component 166. Thereby, light emitted from the light-emitting component 166 enters the light guide structure 168 from the third portion 1686, passes through the first portion 1682, and exits the light guide structure 168 from the second portion 1684. The third portion 1686 is slightly tapered. The cross-section of the third portion 1686 gradually changes; wherein the cross-section of the third portion 1686 near the free end 16860a is smaller than the cross-section of the third portion 1686 near the connecting end 16860b (or the first portion 1682). This facilitates the guidance of light using the light guide structure 168 and also contributes to the uniformity of the light output distribution from the light guide structure 168.

[0032] Therefore, in this embodiment, the light guide structure 168 can make full use of the available space within the front end housing 160. Compared to the light guiding efficiency limited by the diameter of the optical fiber in the prior art, the light guide structure 168 helps to increase the cross-sectional area of ​​the light guide and improve the light guiding efficiency. In addition, the light-emitting component 166 (i.e., the light source) is disposed in the front end 16 of the endoscope (i.e., relatively close to the object to be inspected), so the light transmission attenuation is low and the light emission power of the light-emitting component 166 is also low. Since the light-emitting component 166 is still a distance away from the object to be inspected, the heat generated by the light-emitting component 166 during operation will not affect the object in principle.

[0033] Additionally, in this embodiment, as Figures 2 to 5As shown, the second part 1684 has an annular light-emitting surface 1684b, located on one side of the component accommodating space 1684a and adjacent to a lens 164a of the image capturing component 164. Compared to the illumination formed by a point light source from the end of an optical fiber in the prior art, the annular light-emitting surface 1684b helps to uniformly illuminate objects in front of the endoscope front end 16; that is, it helps to more easily obtain images that meet image quality specifications.

[0034] In this embodiment, the free end 16860a of the third part 1686 serves as a light-incident surface 1686a, and the light emitted by the light-emitting component 166 enters the light guide structure 168 via the light-incident surface 1686a. The light-incident surface 1686a is flat. The light-emitting component 166 has a light-emitting surface 166a, parallel to the light-incident surface 1686a. In practice, the light-incident surface 1686a and the light-emitting surface 166a are bonded together by a transparent photoresist 170 (marked as...). Figure 5 (in the middle) combined. In addition, if the light guide structure 168 does not have a third part 1686, the free end of the first part 1682 serves as a light-incident surface to receive the light emitted by the light-emitting component 166.

[0035] To increase the uniformity of the light distribution in the self-guiding light structure 168, the light-incident surface of the light guide structure 168 can be designed and adjusted, as can the relative position between the light-incident surface of the light guide structure 168 and the light-emitting surface (or nominal light-emitting direction) of the light-emitting component 166. For simplicity, in the following text and related figures, the light guide structure 168 is simplified to lack the third part 1686. Figure 8 As shown (section lines are not shown for simplification), the free end 1682a' of the first portion 1682 serves as a flat light-incident surface 1682c. The normal 1682d of the flat light-incident surface 1682c forms an acute angle 168b with the length direction 168a. The light-exiting surface 166a is parallel to the flat light-incident surface 1682c. This allows more light rays (from the flat light-incident surface 1682c) to enter the light guide structure 168 at a larger angle to the length direction 168a, resulting in more light refracting out of the light guide structure 168 at a larger angle. This helps increase the uniformity of the light distribution from the light guide structure 168 and also helps to more easily obtain a qualified image (e.g., avoiding overexposure). In practice, the acute angle 168b can be greater than 0 degrees but not greater than 15 degrees. Furthermore, if the light-emitting surface 166a is close enough to the light-receiving surface 1682c (for example, about 0.10 mm to 0.15 mm) and there is a transparent light-receiving adhesive filling the space between them, then when the acute angle 168b is 15 degrees, the uniformity of the light distribution will be significantly increased.

[0036] In another instance (such as) Figure 9 As shown), with Figure 8Similar to the previous method, but with the flat light-incident surface 1682c perpendicular to the length direction 168a. The orientation of the light-emitting component 166 is adjustable, which can be achieved by using an adjustment mechanism 172 (e.g., including rotation and one- or two-dimensional movement) to adjustably position the light-emitting component 166 on the circuit board 162. The adjustment mechanism 172 can be set at the factory or by the user afterwards (e.g., via operating the control handle 12, through the circuit board 162). Similarly, more light can enter the light guide structure 168 (from the flat light-incident surface 1682c) at a larger angle to the length direction 168a, so that more light can exit the light guide structure 168 at a larger angle of refraction. This helps to increase the uniformity of the light distribution from the light guide structure 168 and also helps to obtain qualified images more easily. In practice, because the adjustment mechanism 172 can adjust the direction of the light-emitting component 166 relative to the flat light-incident surface 1682c, the flat light-incident surface 1682c does not need to be perpendicular to the length direction 168a and can form other angles with the length direction 168a according to various requirements, which will not be elaborated further. In addition, the two methods mentioned above for increasing the uniformity of the light distribution of the self-guiding structure 168 also apply to the light-incident surface 1686a of the third part 1686 (i.e., located at the free end 16860a), which will not be elaborated further.

[0037] Please see Figure 10 A method for manufacturing a light guide structure (such as the aforementioned light guide structure 168) includes providing a light-transmitting structure 20, as shown in step S102. For simplicity, the component references for the light guide structure 168 will, in principle, be used throughout the text. Furthermore, for simplicity of illustration, structures mentioned below will be shown in sectional views, but without section lines. Figure 11 As shown, the light-transmitting structure 20 (its dimensions are exaggerated) extends along the length direction 168a with a single cross-section and has a first end 20a and a second end 20b in the length direction 168a opposite to the first end 20a. For a description of the cross-section of the light-transmitting structure 20, please refer to the description related to the first portion 1682 of the light guide structure 168, which will not be repeated here. In practice, the light-transmitting structure 20 may be, but is not limited to, extruded.

[0038] Subsequently, the method shapes the portion 202 of the light-transmitting structure 20 with the second end 20b, such that this shaped portion extends along the length direction 168a with a varying cross-section, as shown in step S104. In one example, as... Figure 11 and Figure 12 As shown, step S104 includes shaping a portion 202 of the light-transmitting structure 20 using a mold 22; wherein, this shaped portion 202 (equivalent to the second portion 1684) is as follows: Figure 12As shown. To increase the material flowability of part 202, step S104 may include heating the mold 22 before shaping part 202 of the light-transmitting structure 20. Furthermore, for a description of the cross-section of this shaped part 202, please refer to the description related to the cross-section of the second part 1684 of the light-guiding structure 168, which will not be repeated here. In practice, the contour of this shaped part 202 depends on the design of the mold 22. In this example, part 202 is shaped into the second part 1684. Therefore, in step S104, the method uses the mold 22 to shape the part 202 of the light-transmitting structure 20 with the second end 20b, such that this shaped part 202 (corresponding to the second part 1684) has a component receiving space 1684a and an annular light-emitting surface 1684b located on one side of the component receiving space 1684a (see...). Figures 2 to 5 In practice, the shape of this shaping part 202 and the size of the component accommodating space 1684a can be formed as needed (e.g., through design module 22), without being limited by the structure of the first part 1682, thereby increasing the overall structural adaptability of the light guide structure 168.

[0039] Subsequently, the method shapes the light-transmitting structure 20 with a portion 204 having a first end 20a, such that this shaped portion 204 extends along the length direction 168a with a varying cross-section, as shown in step S106. As shown in Figure 13, this shaped portion 204 serves as the third portion 1686 (see Figure 13). Figures 3 to 5 For a description of the cross-section of this shaped portion 204, please refer to the description related to the cross-section of the third portion 1686 of the light guide structure 168, which will not be repeated here. Furthermore, in this example, the free end (corresponding to the first end 20a) of this shaped portion 204 (equivalent to the third portion 1686) serves as a light-incident surface 1686a. Similarly, the shaping of the third portion 1686 can also be achieved, but is not limited to, by another mold. Additionally, in Figure 13, the light-transmitting structure 20, other than the second and third portions 1684 and 1686, serves as the first portion 1682.

[0040] As explained above, to increase the uniformity of the light output distribution of the self-guiding light structure 168, the light incident surface of the light guiding structure 168 can be further shaped. For simplicity, the following explanation will be based on... Figure 12 As shown in Figures 10 and 14, this method shapes the first end 20a of the light-transmitting structure 20 to form a flat light-incident surface 1682c (see Figure 10). Figure 9 As shown in step S108. The normal 1682d of the flat incident light surface 1682c forms an acute angle 168b with the length direction 168a. For further explanation of the flat incident light surface 1682c, please refer to the relevant descriptions and figures above; further details will not be provided here.

[0041] Please see Figure 15Another method for manufacturing a light guide structure (such as the aforementioned light guide structure 168) is similar to the method described above. The difference lies in the molding of the second part 1684. For simplicity, the following description will focus on the molding of the second part 1684. For explanations of the molding of other parts of the light guide structure 168 and their variations, please refer to the relevant descriptions and figures above, which will not be repeated here. As shown in Figure 15, this method prepares to provide a light-transmitting structure 20, as shown in step S202. Figure 16 (or refer to) Figure 11 As shown in the figure, the light-transmitting structure 20 (its size is exaggerated) extends along the length direction 168a with a single cross section and has a first end 20a and a second end 20b in the length direction 168a relative to the first end 20a.

[0042] After that, as Figure 15 and Figure 16 As shown, the method provides a mold 24 having a cavity 242, as shown in step S204. The method then places a light-transmitting structure 20 within the mold 24, such that the second end 20b is exposed within the cavity 242, as shown in step S206. The method then fills the cavity 242 with a material 26 (e.g., but not limited to injection molding), as shown in step S208. Subsequently, the method cures the material 26 within the cavity 242 such that the cured material 26 (as the second portion 1684) is directly bonded to the second end 20b and extends along the length direction 168a with a varying cross-section, as shown in step S210. The demolded workpiece is as follows: Figure 13 As shown, further details are omitted. Furthermore, depending on the choice of material 26, material 26 can be cured in different ways. For example, if material 26 is a photopolymer, then in step S210, the method involves using light (e.g., ultraviolet light) to harden material 26 within the mold cavity 242; wherein the mold 24 is made of a material that is transparent to ultraviolet light. Similarly, in practice, the shape of the second part 1684 (i.e., the cured material) and the dimensions of the component accommodating space 1684a of the second part 1684 can be formed as needed (e.g., by designing the dimensions of the mold cavity 242), without being limited by the structure of the first part 1682, thereby increasing the overall structural adaptability of the light guide structure 168.

[0043] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

[0044] Symbol Explanation

[0045] 1: Endoscopy

[0046] 12: Control handle

[0047] 14: Insertion tube

[0048] 16: Endoscope front end

[0049] 160: Front shell

[0050] 162: Circuit Board

[0051] 164: Image Capture Component

[0052] 164a: Lens

[0053] 166: Light-emitting components

[0054] 166a: Light-emitting surface

[0055] 168: Light guide structure

[0056] 168a: Length direction

[0057] 168b: Acute angle

[0058] 1682: Part One

[0059] 1682a, 1682b: End

[0060] 1682a': Free End

[0061] 1682c: Flat incident light surface

[0062] 1682d: Normal Direction

[0063] 1684: Part Two

[0064] 1684a: Component containment space

[0065] 1684b: Annular section light-emitting surface

[0066] 1686: Part Three

[0067] 1686a: Incident surface

[0068] 16860a: Free End

[0069] 16860b: Connector

[0070] 170: Transparent Glossy Film

[0071] 172: Adjustment mechanism

[0072] 20: Light-transmitting structure

[0073] 20a: First end

[0074] 20b: Second end

[0075] 202, 204: Partial

[0076] 22,24: Mold

[0077] 242: Mold cavity

[0078] 26: Materials

[0079] S102, S104, S106, S108, S202, S204, S206, S208, S210: Implementation steps.

Claims

1. A light guide structure fixed above a circuit board in an endoscope for guiding light in a lengthwise direction in an endoscope, characterized by, The light guide structure comprises: a first portion proximate to the light emitting component and extending along the length direction with a single cross section, the cross section of the first portion being an arc segment with a central angle greater than 180 degrees and being adapted to the profile of the circuit board; and a second portion extending along the length direction with a varying cross section and being connected to the first portion at one end of the length direction, the outer side of the cross section of the portion proximate to the first portion being an arc shape with a central angle greater than 180 degrees, the inner side of the cross section of the portion proximate to the first portion being an n-shaped, and the portion distal to the first portion being an arc-shaped thin shell, wherein the second portion is formed by a portion shaped directly extending from the end of the first portion or by additional material formed by molding directly combined to the end of the first portion.

2. The light guide structure of claim 1, wherein The second portion has a component accommodation space.

3. The light guide structure of claim 2, wherein The second portion has a ring segment light exit surface located at one side of the component accommodation space.

4. The light guide structure of claim 1, wherein The light guide structure further comprises a third portion connected to the other end of the first portion relative to the second portion and extending along the length direction with a varying cross section.

5. The light guide structure of claim 1, wherein, The light guide structure has a flat light entrance surface, the normal of the flat light entrance surface forming an acute angle with the length direction.

6. The light guide structure of claim 1, wherein, The first portion and the second portion are formed of the same material and are a single member.

7. An endoscope tip, comprising: The endoscope tip comprises: a circuit board; an image capturing component disposed on the circuit board; a light emitting component disposed on the circuit board, the light emitting component being located at an end of the circuit board distal to the image capturing component; and a light guide structure disposed on the circuit board to guide light emitted by the light emitting component along a length direction, the light guide structure comprising: a first portion proximate to the light emitting component and extending along the length direction with a single cross section, the cross section of the first portion being an arc segment with a central angle greater than 180 degrees and being adapted to the profile of the circuit board; and a second portion extending along the length direction with a varying cross section and being connected to the first portion at one end of the length direction, the outer side of the cross section of the portion proximate to the first portion being an arc shape with a central angle greater than 180 degrees, the inner side of the cross section of the portion proximate to the first portion being an n-shaped, and the portion distal to the first portion being an arc-shaped thin shell, wherein the second portion is formed by a portion shaped directly extending from the end of the first portion or by additional material formed by molding directly combined to the end of the first portion.

8. The endoscope tip of claim 7, wherein: The second portion has a component accommodation space, the image capturing component being at least partially accommodated in the component accommodation space.

9. The endoscope tip of claim 8, wherein The second portion has a ring segment light exit surface located at one side of the component accommodation space and adjacent to a lens of the image capturing component.

10. The endoscope tip of claim 7, wherein: The light guide structure comprises a third portion connected to the other end of the first portion relative to the second portion and extending along the length direction with a varying cross section, the third portion being located between the first portion and the light emitting component.

11. The endoscope tip of claim 7, wherein: The light guide structure has a flat light-in surface, a normal of the flat light-in surface forms an acute angle with the length direction, and the light emitting component has a light-out surface, the light-out surface is parallel to the flat light-in surface.

12. The endoscope tip of claim 11, wherein: The flat light-in surface and the light-out surface are combined by transparent optical cement.

13. The endoscope tip of claim 7, wherein: The light guide structure has a flat light-in surface, and the light emitting component has a light-out surface, the light-out surface and the flat light-in surface are not parallel.

14. The endoscope tip of claim 7, wherein: The first part and the second part are formed by the same material, and the first part and the second part are single members.

15. The endoscope tip of claim 7, wherein: The endoscope front end further comprises a front end shell, the front end shell contains the circuit board, the image capturing component, the light emitting component and the light guide structure.

16. The endoscope tip of claim 7, wherein: The direction of the light emitting component is adjustable.

17. A method for manufacturing a light guide structure according to any one of claims 1-6, characterized by The method comprises the following steps: (a) providing a light-transmissive structure, the light-transmissive structure extends along a length direction with a single cross section and has a first end and a second end opposite to the first end along the length direction; and (b) shaping a part of the second end of the light-transmissive structure, so that the shaped part extends along the length direction with a variable cross section, thereby completing the light guide structure.

18. The method of claim 17, wherein, The step (b) comprises shaping the part of the light-transmissive structure using a mold.

19. The method of claim 18, wherein, The step (b) comprises heating the mold before shaping the part of the light-transmissive structure using the mold.

20. The method of claim 17, wherein, The step (b) comprises shaping the part of the second end of the light-transmissive structure, so that the shaped part has a component accommodation space.

21. The method of claim 20, wherein, The step (b) comprises shaping the part of the second end of the light-transmissive structure, so that the shaped part has a ring segment light-out surface located at one side of the component accommodation space.

22. The method of claim 17, wherein, The method further comprises the following steps: (c) shaping the first end of the light-transmissive structure to form a flat light-in surface, a normal of the flat light-in surface forms an acute angle with the length direction.

23. A method for manufacturing a light guide structure according to any one of claims 1-6, characterized by The method comprises the following steps: (a) providing a light-transmissive structure, the light-transmissive structure extends along a length direction with a single cross section and has a first end and a second end opposite to the first end along the length direction; (b) providing a mold with a mold cavity; (c) arranging the light-transmissive structure in the mold, so that the second end is exposed in the mold cavity; (d) filling the mold cavity with a material; and (e) solidifying the material in the mold cavity, so that the solidified material is directly combined to the second end and extends along the length direction with a variable cross section, thereby completing the light guide structure.

24. The method of claim 23, wherein, The mold is light-transmissive, the material is a photopolymer, and the step (d) comprises using a light to harden the material in the mold cavity.

25. The method of claim 23, wherein, The method further comprises the following steps: (f) shaping the first end of the light-transmissive structure to form a flat light-in surface, a normal of the flat light-in surface forms an acute angle with the length direction.

Images