Endoscope optical imaging system, endoscope imaging system, and endoscope device

Abstract

The invention discloses an endoscope optical imaging system, which comprises an objective lens group, an internal sheath, an external sheath, an illumination optical fiber and an optical waveguide lens, and is characterized in that the first surface of the optical waveguide lens is sequentially provided with a first transmission surface, a second reflection surface and a third transmission surface from outside to inside; the second surface is provided with a second transmission surface; the inclined surface is provided with a first reflecting surface; wherein the illumination light is incident to the first reflecting surface through the first transmission surface to be totally reflected, then is incident to the second reflecting surface, is totally reflected again and then is incident to the second transmission surface, and the imaging light is incident to the second transmission surface and then is emergent to the objective lens group through the third transmission surface to be imaged. According to the optical imaging system, by optimizing the optical path design, the local illumination effect and imaging quality of the close-range observation target object are ensured. According to the imaging system, an illumination lens does not need to be additionally arranged at the side end, a traditional rod-shaped lens used for transmitting images is omitted, and the size of the endoscope is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of medical devices, and particularly relates to an endoscopic optical imaging system, an endoscopic imaging system and an endoscopic device. Background Art

[0002] An endoscope is a medical device that combines optics, electronics and mechanical technologies. It can enter the human body through natural cavities such as the oral cavity to clearly display lesions that cannot be observed by X-rays, helping doctors quickly locate the lesions, so as to formulate a more accurate treatment plan.

[0003] At present, there are mainly two illumination methods for endoscopes: one is fiber optic light guiding illumination, which directly illuminates the observation area by using the divergence angle characteristics of the optical fiber; the other is common path illumination, in which part of the illumination light path and the imaging light path share the same path. After the illumination light irradiates the sample through the imaging system, the reflected light or fluorescence generated by excitation of the sample is used for imaging.

[0004] For the fiber optic illumination method, when the endoscope is close to the observed tissue, the optical fibers at the edge are difficult to effectively illuminate the central area of the tissue. Especially when the endoscope body is in contact with the tissue, the central area cannot obtain illumination at all, seriously affecting the imaging quality.

[0005] For the common path illumination method, the illumination light is introduced into the imaging light path through a beam splitter. However, to achieve uniform illumination, it is still necessary to add an illumination lens system between the illumination optical fiber and the beam splitter, which significantly increases the volume of the side-end structure and is not conducive to the miniaturization design of the endoscope. At the same time, a rod lens is also required to transmit the image in the endoscope, and the setting of the rod lens is also not conducive to the miniaturization design of the endoscope.

[0006] Therefore, in view of the above technical problems, it is necessary to provide an endoscopic optical imaging system, an endoscopic imaging system and an endoscopic device. Summary of the Invention

[0007] The purpose of the present invention is to provide an endoscopic optical imaging system, an endoscopic imaging system and an endoscopic device, which can solve the problems of uneven illumination and large volume of the endoscope mentioned above.

[0008] To achieve the above purpose, a specific embodiment of the present invention provides an endoscopic optical imaging system, and the technical solution is as follows: An endoscopic optical imaging system includes an inner sheath for mounting and accommodating an objective lens group, and an outer sheath sleeved around the outer periphery of the inner sheath. An annular space is formed between the inner sheath and the outer sheath, and illumination optical fibers are arranged in the annular space to provide illumination light; The optical imaging system further includes a light waveguide lens disposed at the same end of the inner mirror sheath and the outer mirror sheath. The light waveguide lens includes a first surface close to the illumination optical fiber, a second surface far from the illumination optical fiber and parallel to the first surface, and an inclined surface connecting the first surface and the second surface; The first surface is sequentially provided with a first transmission surface for transmitting illumination light, a second reflection surface for totally reflecting illumination light, and a third transmission surface for transmitting imaging light from outside to inside; the second surface is provided with a second transmission surface for transmitting illumination light and imaging light; the inclined surface is provided with a first reflection surface for totally reflecting illumination light; Wherein, the illumination light is incident on the first reflection surface through the first transmission surface and totally reflected, then incident on the second reflection surface and totally reflected again, and then incident on the second transmission surface. The imaging light is incident through the second transmission surface and exits through the third transmission surface to form an image through the objective lens assembly.

[0009] In one or more embodiments of the present invention, the illumination light incident into the light waveguide lens through the first transmission surface is sequentially reflected by the first reflection surface and the second reflection surface to the second surface to form an illumination area. Wherein, the illumination area is a simply connected area, and the second transmission surface is located within the illumination area.

[0010] In one or more embodiments of the present invention, the light waveguide lens satisfies the following conditional formula:

[0011] Wherein, φ is the illumination diameter formed by the first illumination beam or the second illumination beam on the second surface in the reference section; L1 is the width of the first illumination beam or the second illumination beam; θ is the included angle between the first surface and the inclined surface of the light waveguide lens in the reference section; The first illumination beam is the illumination light incident into the light waveguide lens through the first reference incident surface, the second illumination beam is the illumination light incident into the light waveguide lens through the second reference incident surface. The first reference incident surface and the second reference incident surface are the first transmission surfaces of two opposite parts in the reference section, and the reference section is the plane obtained by cutting the light waveguide lens with a plane passing through the central axis of the light waveguide lens.

[0012] In one or more embodiments of the present invention, the illumination light incident into the light waveguide lens through the first transmission surface satisfies: The centers of the first illumination beam and the second illumination beam converge at the center of the second transmission surface, and the illumination diameters of the first illumination beam and the second illumination beam are both greater than or equal to the reference diameter of the second transmission surface; or, The adjacent edges of the first illumination beam and the second illumination beam converge at the center of the second transmission surface, and the illumination diameters of the first illumination beam and the second illumination beam are both greater than or equal to the reference radius of the second transmission surface; Wherein, the first illumination beam is the illumination light incident into the optical waveguide lens through the first reference incident surface, the second illumination beam is the illumination light incident into the optical waveguide lens through the second reference incident surface, the first reference incident surface and the second reference incident surface are the first transmission surfaces of two opposite parts on the reference section, the reference diameter and the reference radius are respectively the diameter and the radius of the second transmission surface, and the reference section is the plane obtained by cutting the optical waveguide lens with a plane passing through the central axis of the optical waveguide lens.

[0013] In one or more embodiments of the present invention, the optical waveguide lens satisfies the following conditional formula:

[0014] Wherein, L is the diameter of the first surface of the optical waveguide lens; L1 is the width of the first illumination beam or the second illumination beam; L2 is the distance from the center of the first illumination beam or the second illumination beam to the center of the optical waveguide lens; θ is the angle between the first surface of the optical waveguide lens and the inclined surface on the reference section; h 0 is the thickness of the optical waveguide lens; h 1 is the distance between the second surface of the optical waveguide lens and the object surface; n 0 is the refractive index of the optical waveguide lens; n 2 is the refractive index of the medium on the side away from the optical waveguide lens of the second surface of the optical waveguide lens.

[0015] In one or more embodiments of the present invention, the illumination light incident into the optical waveguide lens through the first transmission surface is reflected to the second transmission surface after one reflection on both the first reflection surface and the second reflection surface, and the optical waveguide lens satisfies the following conditional formula:

[0016] Wherein, L is the diameter of the first surface of the optical waveguide lens; L1 is the width of the first illumination beam or the second illumination beam; L2 is the distance from the center of the first illumination beam or the second illumination beam to the center of the optical waveguide lens; θ is the angle between the first surface of the optical waveguide lens and the inclined surface on the reference section; θ 2 is the refractive angle when the illumination light with an incident angle of θ 1 is incident into the optical waveguide lens from the first transmission surface; h 0 is the thickness of the optical waveguide lens; The first illumination beam is the illumination light incident into the optical waveguide lens through the first reference incident surface, and the second illumination beam is the illumination light incident into the optical waveguide lens through the second reference incident surface. The first reference incident surface and the second reference incident surface are the first transmission surfaces of two opposite parts on the reference cross-section, and the reference cross-section is the plane obtained by cutting the optical waveguide lens with a plane passing through the central axis of the optical waveguide lens.

[0017] In one or more embodiments of the present invention, the first reflection surface and / or the second reflection surface are formed by setting a total reflection film; and / or, The optical waveguide lens satisfies the following conditional formula:

[0018] Wherein, θ is the angle between the first surface of the optical waveguide lens and the inclined surface on the reference cross-section; θ 2 is the refraction angle of the illumination light with an incident angle of θ 1 when it is incident from the first transmission surface into the optical waveguide lens; n 0 is the refractive index of the optical waveguide lens; n 1 is the refractive index of the medium on the side of the first surface of the optical waveguide lens away from the optical waveguide lens; n 2 is the refractive index of the medium on the side of the second surface of the optical waveguide lens away from the optical waveguide lens; The reference cross-section is the plane obtained by cutting the optical waveguide lens with a plane passing through the central axis of the optical waveguide lens.

[0019] In one or more embodiments of the present invention, the optical waveguide lens satisfies the following conditional formula:

[0020]

[0021] Wherein, θ is the angle between the first surface of the optical waveguide lens and the inclined surface on the reference cross-section; θ 1 is the incident angle of the illumination light incident from the first transmission surface; θ 2 is the incident angle of θ 1 when the illumination light with an incident angle of n 1 is incident from the first transmission surface into the optical waveguide lens; n 0 is the refractive index of the optical waveguide lens; n 1 is the refractive index of the medium on the side of the first surface of the optical waveguide lens away from the optical waveguide lens; 2 is the refractive index of the medium on the side of the second surface of the optical waveguide lens away from the optical waveguide lens;

[0022] In one or more embodiments of the present invention, the optical waveguide lens includes a first lens body, a second lens body, and a third lens body that are sleeved from outside to inside in sequence; The first transmission surface and the first reflection surface are disposed on the first lens body, the second reflection surface is disposed on the second lens body, the second transmission surface is disposed on the third lens body, or the second lens body and the third lens body, and the third transmission surface is disposed on the third lens body.

[0023] In one or more embodiments of the present invention, the first lens body, the second lens body, and the third lens body form the first surface on the first side surface in the axial direction of the optical waveguide lens; The second lens body and the third lens body form the second surface on the second side surface in the axial direction of the optical waveguide lens; The first lens body and the second lens body form the inclined surface on the outer peripheral side surface between the first surface and the second surface in the axial direction of the optical waveguide lens.

[0024] In one or more embodiments of the present invention, the illumination light incident into the optical waveguide lens through the first transmission surface is 100% transmitted at the fitting interface between the first lens body and the second lens body and at the fitting interface between the second lens body and the third lens body.

[0025] In one or more embodiments of the present invention, a collimating objective lens is installed between the light-emitting surface of the illumination optical fiber and the objective lens module, and the focus of the collimating objective lens is aligned with the light-emitting end face of the illumination optical fiber; and / or, The second surface of the optical waveguide lens is perpendicular to the axis of the internal lens sheath; and / or, The second surface of the optical waveguide lens is flush with the end face of the external lens sheath.

[0026] A specific embodiment of the present invention further provides an endoscope optical imaging system, and the technical solution is as follows: An endoscope imaging system includes the above-mentioned endoscope optical imaging system. Among them, the endoscope imaging system includes a photoelectric conversion module disposed inside the internal lens sheath and at the image distance position of the objective lens group for directly receiving imaging signals.

[0027] A specific embodiment of the present invention further provides an endoscope device, and the technical solution is as follows: An endoscope device includes the above-mentioned endoscope optical imaging system. Among them, the endoscope device includes a light source that provides illumination light, an illumination optical fiber with one end connected to the light source and the other end extending and disposed inside the internal lens sheath and the external lens sheath for transmitting illumination light, a photoelectric conversion module disposed inside the internal lens sheath and at the image distance position of the objective lens group for receiving imaging signals, and a signal transmission line for transmitting the signals received by the photoelectric conversion module to a signal processing terminal.

[0028] In one or more embodiments of the present invention, one of the light source and the signal processing terminal is provided with a connection end, and the connection end is integrated with an optical signal interface and an optoelectronic signal interface; the illumination optical fiber is connected to the light source through the optical signal interface, and the signal transmission line is connected to the signal processing terminal through the optoelectronic signal interface.

[0029] In one or more embodiments of the present invention, the endoscope device includes a handle, one end of the handle is connected to the external sheath, and the other end is connected to the light source and the signal processing terminal through a wire harness, and the wire harness includes the illumination optical fiber and the signal transmission line.

[0030] Compared with the prior art, in the illumination optical path of the endoscope optical imaging system of the present invention, the illumination light conducted by the illumination optical fiber is incident through the first transmission surface and finally exits from the second transmission surface. In the imaging optical path, the imaging light returning from the imaging target is incident through the second transmission surface and then exits through the third transmission surface to the objective lens group for imaging. In the above illumination optical path, the illumination light can be incident from the area of the relative side edge of the optical waveguide lens and then exit from the relative middle area of the optical waveguide lens. Such a setting method can match the optical path structure design of fiber illumination, and through the control of the illumination light shifting towards the center, it ensures the illumination effect of the observed area of the target object when in close contact with the target object and guarantees the imaging quality. At the same time, the endoscope imaging system of the present invention does not need to add an illumination lens between the illumination optical fiber and the beam splitter plate, and omits the traditional rod lens for transmitting images, significantly reducing the volume of the endoscope. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments recorded in the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0032] Figure 1 Structural schematic diagram of an endoscope optical imaging system in an embodiment of the present invention; Figure 2 Schematic cross-sectional structure diagram of an optical waveguide lens in an embodiment of the present invention; Figure 3 Top view of the first surface of an optical waveguide lens in an embodiment of the present invention; Figure 4 Schematic diagram of the optical path of illumination light in an optical waveguide lens in an embodiment of the present invention; Figure 5Schematic diagram of partial parameters of the optical waveguide lens in an embodiment of the present invention; Figure 6 Schematic diagram of the optical path of another situation of the illumination light in the optical waveguide lens in an embodiment of the present invention; Figure 7 Schematic diagram of the structure of the endoscopic optical imaging system in another embodiment of the present invention; Figure 8 Schematic diagram of the structure of the light source and the signal processing terminal in an embodiment of the present invention; Figure 9 Schematic diagram of the structure of the handle in an embodiment of the present invention.

[0033] Description of main reference numerals: 1. Objective lens group; 2. Inner sheath; 3. Outer sheath; 4. Illumination optical fiber; 5. Optical waveguide lens; 51. First lens body; 52. Second lens body; 53. Third lens body; 54. First surface; 541. First transmission surface; 542. Second reflection surface; 543. Third transmission surface; 55. Second surface; 551. Second transmission surface; 56. Inclined surface; 561. First reflection surface; 6. Collimating objective lens; 7. Light source; 8. Signal processing terminal; 9. Connection end; 10. Handle; 11. Photoelectric conversion module; 12. Signal transmission line. Detailed implementation manners

[0034] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present invention.

[0035] An endoscope is a medical device that enters the human body through a natural cavity to examine lesions, and its imaging depends on effective illumination. In traditional fiber illumination, a dark area is likely to appear in the central area when approaching the tissue. Although common-path illumination can improve the uniformity, it is necessary to add a lens at the side end between the illumination optical fiber and the beam splitter, resulting in an increase in its volume. The endoscopic optical imaging system of the present invention solves the problems of uneven illumination and excessive volume of the endoscopic imaging system while ensuring the imaging quality. The following introduces the endoscopic optical imaging system of the present invention.

[0036] Refer to Figure 1, in an embodiment of the present invention, an endoscopic optical imaging system is provided, which includes an inner sheath 2 for mounting and accommodating an objective lens group 1, and an outer sheath 3 sleeved around the outer periphery of the inner sheath 2. An annular space is formed between the inner sheath 2 and the outer sheath 3, and illumination optical fibers 4 are arranged in the annular space to provide illumination light. The illumination optical fibers 4 can be connected to an illumination host to provide illumination light.

[0037] Referring to Figure 1 and Figure 2 , the optical imaging system further includes an optical waveguide lens 5 provided at the same end of the inner sheath 2 and the outer sheath 3. The optical waveguide lens 5 includes a first surface 54 close to the illumination optical fibers 4, a second surface 55 far from the illumination optical fibers 4 and parallel to the first surface 54, and an inclined surface 56 connecting the first surface 54 and the second surface 55. In this embodiment, taking the optical waveguide lens 5 being set as a frustum of a cone as an example for exemplary elaboration. Therefore, the above-mentioned first surface 54 and second surface 55 can be understood as two opposite circular optical surfaces of the frustum of a cone, and the inclined surface 56 can be understood as the optical surface on the circumferential side of the frustum of a cone in a three-dimensional space.

[0038] Referring to Figure 3 and Figure 4 , the first surface 54 is sequentially provided with a first transmission surface 541 for transmitting illumination light, a second reflection surface 542 for totally reflecting illumination light, and a third transmission surface 543 for transmitting imaging light from outside to inside; the second surface 55 is provided with a second transmission surface 551 for transmitting illumination light and imaging light; the inclined surface 56 is provided with a first reflection surface 561 for totally reflecting illumination light.

[0039] In the illumination optical path of the endoscopic optical imaging system in this embodiment, the illumination light conducted by the illumination optical fibers 4 is incident on the first reflection surface 561 through the first transmission surface 541, undergoes total reflection and then is incident on the second reflection surface 542, and undergoes total reflection again and then is incident on the second transmission surface 551 for transmission. Correspondingly, in the imaging optical path, the imaging light returning from the imaging target is incident through the second transmission surface 551 and exits through the third transmission surface 543 to the objective lens group 1 for imaging.

[0040] It can be seen that in the above illumination optical path, the illumination light can be incident from the area at the opposite side edges of the optical waveguide lens 5 and exit from the relatively middle area of the optical waveguide lens 5. Such a setting method can match the optical path structure design of fiber illumination, and through the control of the illumination light shifting towards the center, it ensures the illumination effect on the local area of the target object when in close contact with the target object and guarantees the imaging quality.

[0041] It can be understood that the internal and external positional relationships of the first transmissive surface 541, the second reflective surface 542, and the third transmissive surface 543 are relative. For example, the first transmissive surface 541 can be disposed at the outer peripheral edge region of the first surface 54 or at a region at a certain distance from the outer peripheral edge of the first surface 54; the third transmissive surface 543 can be disposed at the central region of the first surface 54 or deviate from the center of the first surface 54. The present application does not limit this. Moreover, the first reflective surface 561 can be disposed at a part or all of the inclined surface 56 and can be disposed in cooperation with the optical path of the illumination light.

[0042] Combined with Figure 3 , in this embodiment, taking the first transmissive surface 541 and the second reflective surface 542 being circular rings and the second transmissive surface 551 being circular as an example, the optical waveguide lens 5 of this embodiment is described exemplarily. In other embodiments, the first transmissive surface 541, the second reflective surface 542, and the second transmissive surface 551 can also be other shapes, and the present application does not make specific limitations on this. Correspondingly, the outer sheath 3 and the inner sheath 2 can be set to be cylindrical, and the optical fibers can be evenly arranged at equal circumferential intervals between the outer sheath 3 and the inner sheath 2 to ensure the uniformity of the illumination light.

[0043] In this embodiment, referring to Figure 4 and Figure 6 , the illumination light incident into the optical waveguide lens 5 through the first transmissive surface 541 is reflected by the first reflective surface 561 and the second reflective surface 542 in sequence to the second surface 55 to form an illumination area, wherein the illumination area is a simply connected area, and the second transmissive surface 551 is located within the illumination area. The illumination area being a simply connected area can effectively ensure its integrity, and then comprehensively cover the imaging area of the tissue to ensure the integrity and clarity of the tissue imaging.

[0044] Referring to Figure 4 Figure 5 , to more clearly illustrate the endoscopic optical imaging system in this embodiment, the parameters of the optical waveguide lens 5 in this embodiment are described first as follows: φ is the illumination diameter formed by the first illumination beam or the second illumination beam on the second surface 55 in the reference section; L is the diameter of the first surface of the optical waveguide lens 5; L1 is the width of the first illumination beam or the second illumination beam; L2 is the distance from the center of the first illumination beam or the second illumination beam to the center of the optical waveguide lens 5; θ is the angle between the first surface 54 and the inclined surface 56 of the optical waveguide lens 5 in the reference section; θ 1 is the incident angle of the illumination light incident from the first transmissive surface 541; θ 2 is the incident angle of θThe refraction angle at which the illumination light of 1 is incident on the light waveguide lens 5 from the first transmission surface 541; h 0 is the thickness of the light waveguide lens 5; h 1 is the distance between the second surface 55 of the light waveguide lens 5 and the object surface; n 0 is the refractive index of the light waveguide lens 5; n 1 is the refractive index of the medium on the side of the first surface 54 of the light waveguide lens 5 away from the light waveguide lens 5; n 2 is the refractive index of the medium on the side of the second surface 55 of the light waveguide lens 5 away from the light waveguide lens 5.

[0045] Among them, the first illumination beam is the illumination light incident on the light waveguide lens 5 through the first reference incident surface, and the second illumination beam is the illumination light incident on the light waveguide lens 5 through the second reference incident surface. The first reference incident surface and the second reference incident surface are the first transmission surfaces 541 of two opposite parts on the reference section, and the reference section is the plane obtained by cutting the light waveguide lens 5 with a plane passing through the central axis of the light waveguide lens 5. In this embodiment, the corresponding first illumination beam and second illumination beam on the reference section are symmetrically arranged. Figures 4 to 6 The cross-section of the shown light waveguide lens 5 is the above-mentioned reference section.

[0046] Refer to Figure 4 , in this embodiment, for a determined optical imaging system, its object-side size is determined. Therefore, it is necessary to make the illumination area larger than the imaging area to ensure that the imaging area of the tissue is illuminated. Based on this, the light waveguide lens 5 satisfies the following conditional formula:

[0047] It should be noted that in this embodiment, φ can be determined according to the optical imaging system, L1 can be determined according to the design requirements, and the θ value of the light waveguide lens 5 can be determined through the above formula. φ, L1 and θ satisfying the above conditional formula can make the illumination light incident from the first transmission surface 541 of the light waveguide lens 5 effectively cover the second transmission surface 551. Among them, theoretically, φ the value can be infinitely large to achieve full coverage of the second transmission surface 551. In this embodiment, its maximum value is restricted, and the purpose is to avoid excessive illumination range so that some light is reflected by the first reflection surface 561, affecting the final imaging effect.

[0048] Refer to Figure 4 and Figure 6 , to ensure the uniformity of illumination of the illumination light on the second transmission surface 551, the illumination light incident on the light waveguide lens 5 through the first transmission surface 541 satisfies: The centers of the first and second illumination beams converge at the center of the second transmissive surface 551, and the illumination diameters of the first and second illumination beams are both greater than or equal to a reference diameter of the second transmissive surface 551. Alternatively, adjacent edges of the first and second illumination beams converge at the center of the second transmissive surface 551, and the illumination diameters of the first and second illumination beams are both greater than or equal to a reference radius of the second transmissive surface 551. The reference diameter and reference radius are the diameter and radius of the second transmissive surface 551, respectively, and the reference cross-section is a plane passing through the central axis of the waveguide lens 5 and intersecting the waveguide lens 5.

[0049] Specifically, the optical waveguide lens 5 in this embodiment satisfies the following conditional formula:

[0050] It should be noted that the ± signs in the above conditional expressions correspond to Figure 4 and Figure 6 It can be understood that the light waveguide lens 5 that meets the above formula can effectively ensure that the imaging area is evenly illuminated, thereby ensuring the final imaging effect.

[0051] Reference Figure 4 In this embodiment, the illumination light incident on the light guide lens 5 through the first transmission surface 541 is reflected once on the first reflection surface 561 and the second reflection surface 542 before being reflected to the second transmission surface 551. The light guide lens 5 satisfies the following conditional formula:

[0052] Reference Figure 4 and Figure 6 In this embodiment, the first reflective surface 561 and / or the second reflective surface 542 are formed by providing a total reflection film. In other embodiments, the first reflective surface 561 can be totally reflected by the material properties of the glass of the light waveguide lens 5. In this case, the light waveguide lens 5 satisfies the following conditional formula:

[0053] Furthermore, to ensure that the illumination light is not reflected on the second transmission surface 551, the light waveguide lens 5 satisfies the following conditional formula:

[0054]

[0055] Considering that the illumination light incident from the first transmission surface 541 is not perpendicular to the first transmission surface 541, there may be a certain error. θ 1 and θThe parameter setting of 2 can further ensure the accuracy of the optical waveguide lens 5. The above are the structural and dimensional requirements for the endoscopic optical imaging system in this application.

[0056] Referring to Figure 2 and Figure 4 In this embodiment, the optical waveguide lens 5 includes a first lens body 51, a second lens body 52, and a third lens body 53 that are nested in sequence from outside to inside; a first transmission surface 541 and a first reflection surface 561 are provided on the first lens body 51, a second reflection surface 542 is provided on the second lens body 52, a second transmission surface 551 is provided on the third lens body 53, or the second lens body 52 and the third lens body 53, and a third transmission surface 543 is provided on the third lens body 53. Specifically, the first lens body 51, the second lens body 52, and the third lens body 53 can be glued together to simplify the manufacturing difficulty of the optical waveguide lens 5.

[0057] The first lens body 51, the second lens body 52, and the third lens body 53 form a first surface 54 on the first side surface in the axial direction of the optical waveguide lens 5; the second lens body 52 and the third lens body 53 form a second surface 55 on the second side surface in the axial direction of the optical waveguide lens 5; the first lens body 51 and the second lens body 52 form an inclined surface 56 on the outer peripheral side surface between the first surface 54 and the second surface 55 in the axial direction of the optical waveguide lens 5.

[0058] The illumination light incident on the optical waveguide lens 5 through the first transmission surface 541 is 100% transmitted at the nested interface between the first lens body 51 and the second lens body 52, and at the nested interface between the second lens body 52 and the third lens body 53. In this embodiment, the first lens body 51 is responsible for the transmission and reflection of light, the second lens body 52 is responsible for the reflection of light, and the third lens body 53 is responsible for the transmission of light. Each lens body plays a different role, which can improve the manufacturing convenience of the endoscopic optical imaging system in this application.

[0059] Among them, according to the endoscopic imaging design principle, the endoscope can be divided into two types: white light imaging and fluorescence imaging. In white light imaging, the illumination light involved in this embodiment is a white light source, and the imaging light is the reflected light of the tissue. In this implementation environment, the third transmission surface 543 of the optical waveguide lens 5 can be set to transmit the imaging light in the full wavelength band. In fluorescence imaging, the illumination light involved in this embodiment is an excitation light source, and the imaging light is the fluorescence generated by the excitation of the excitation light. The excitation light is incident from the first transmission surface 541, exits from the second transmission surface 551 and irradiates the tissue. Based on the principle of photoluminescence, the tissue can be excited by the excitation light to generate fluorescence. At this time, the fluorescence is incident from the second transmission surface 551 and exits from the third transmission surface 543. In this implementation environment, the third transmission surface 543 can be set to transmit fluorescence and block the excitation light.

[0060] Referring to Figure 1 and Figure 2, in this embodiment, the second surface 55 of the optical waveguide lens 5 is perpendicular to the axis of the inner sheath 2; and / or, the second surface 55 of the optical waveguide lens 5 is flush with the end face of the outer sheath 3. In the prior art, the end face of the outer sheath 3 of the endoscope is mostly inclined, and a parallel illumination optical path and imaging optical path are arranged at the position of the inclined surface 56. In this embodiment, the second surface 55 of the optical waveguide lens 5 is perpendicular to the axis of the inner sheath 2, and the second surface 55 of the optical waveguide lens 5 is flush with the end face of the outer sheath 3, so that the endoscope can be close to the imaging area for imaging, so as to realize the adjustment without distance limitation from the imaging area.

[0061] Referring to Figure 7 , in an alternative embodiment, a collimating objective lens 6 is installed between the light-emitting surface of the optical fiber and the objective lens module. The focus of the collimating objective lens 6 is aligned with the light-emitting end face of the optical fiber, and the collimating objective lens 6 can collimate the illumination beam. It can be understood that in other embodiments, if the numerical aperture of the optical fiber itself is relatively low, the collimating objective lens 6 may not be used.

[0062] Referring to Figure 1 , in an embodiment of the present invention, an endoscope imaging system is further provided, including the above-mentioned endoscope optical imaging system. Among them, the endoscope imaging system includes a photoelectric conversion module disposed inside the inner sheath 2 and at the image distance position of the objective lens group 1 for directly receiving imaging signals. In this embodiment, the light conversion module is located on the side of the objective lens group 1 away from the optical waveguide lens 5. The photoelectric conversion module can be a CMOS image sensor or a CCD image sensor. In the prior art, a rod lens is usually arranged inside the endoscope, and the image is transmitted by means of the rod lens. In this embodiment, the photoelectric conversion module is directly arranged at the image distance position of the objective lens group 1, so that the rod lens can be omitted, and further reduce the volume of the endoscope imaging system.

[0063] In the illumination optical path of the endoscope optical imaging system of the present invention, the illumination light conducted by the illumination optical fiber 4 is incident through the first transmission surface 541 and finally exits from the second transmission surface 551. In the imaging optical path, the imaging light returning from the imaging target is incident through the second transmission surface 551 and then exits through the third transmission surface 543 to the objective lens group 1 for imaging. In the above illumination optical path, the illumination light can be incident from the area of the opposite side edge of the optical waveguide lens 5 and then exit from the relatively middle area of the optical waveguide lens ? This setting method can match the optical path structure design of fiber illumination, and through the control of the illumination light shifting towards the center, it ensures the illumination effect of the observed area of the target object when in close contact with the target object and guarantees the imaging quality. At the same time, the endoscope imaging system of the present invention does not need to add an illumination lens between the illumination optical fiber 4 and the beam splitter, and omits the traditional rod lens for transmitting images, significantly reducing the volume of the endoscope.

[0064] Cooperate with reference to Figure 8 andFigure 9 , in an embodiment of the present invention, an endoscope device is further provided, including the above-mentioned endoscope optical imaging system. Wherein, the endoscope device includes a light source 7 for providing illumination light, an illumination optical fiber 4 with one end connected to the light source 7 and the other end extending and disposed inside the inner sheath 2 and the outer sheath 3 for transmitting the illumination light, a photoelectric conversion module 11 disposed inside the inner sheath 2 and at the image distance position of the objective lens group 1 for receiving imaging signals, and a signal transmission line 12 for transmitting the signals received by the photoelectric conversion module to the signal processing terminal 8. When the endoscope device of this embodiment is in use, the light source 7 conducts the illumination light to the optical waveguide lens 5 of the endoscope optical imaging system through the illumination optical fiber 4 to illuminate the imaging target. The imaging light returned by the imaging target can travel to the photoelectric conversion module 11, and finally the photoelectric signal is transmitted to the signal processing terminal 8 through the signal transmission line 12.

[0065] It can be understood that since the endoscope device of this embodiment is provided with the above-mentioned endoscope optical imaging system, by controlling the illumination light to shift towards the center, it ensures the illumination effect of the observed area of the target object when in close contact with the target object, and guarantees the imaging quality.

[0066] Referring to Figure 8 and Figure 9 , in this embodiment, the endoscope device includes a handle 10. One end of the handle 10 is connected to the outer sheath 3, and the other end is connected to the light source 7 and the signal processing terminal 8 through a wire harness. The wire harness includes an illumination optical fiber 4 and a signal transmission line 12. One of the light source 7 and the signal processing terminal 8 is provided with a connection end 9, and the connection end 9 integrates an optical signal interface and an optoelectronic signal interface; the illumination optical fiber 4 is connected to the light source 7 through the optical signal interface, and the signal transmission line 12 is connected to the signal processing terminal 8 through the optoelectronic signal interface. Exemplarily, the connection end 9 can be disposed on the main body of the light source 7, or the connection end 9 can be disposed on the signal processing terminal 8.

[0067] One of the light source 7 and the signal processing terminal 8 is provided with a connection end 9, and the connection end 9 integrates an optical signal interface and an optoelectronic signal interface. When connecting to the endoscope handle 10 through this connection end 9, the situation of mutual entanglement between the optical fiber and the cable can be reduced, thereby ensuring the smooth progress of the on-site operation.

[0068] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above-described exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be embraced within the present invention. Any reference signs in the claims should not be construed as limiting the claims involved.

[0069] In addition, it should be understood that although this specification is described in terms of embodiments, not every embodiment only contains an independent technical solution. This narrative manner of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. An endoscopic optical imaging system, comprising an inner sheath for mounting and accommodating an objective lens group, and an outer sheath sleeved around the outer periphery of the inner sheath. An annular space is formed between the inner sheath and the outer sheath, and illumination optical fibers are arranged in the annular space to provide illumination light. It is characterized in that: The optical imaging system further comprises a waveguide lens disposed at the same end of the inner sheath and the outer sheath. The waveguide lens comprises a first surface close to the illumination optical fibers, a second surface far from the illumination optical fibers and parallel to the first surface, and an inclined surface connecting the first surface and the second surface; On the first surface, a first transmission surface for transmitting illumination light, a second reflection surface for totally reflecting illumination light, and a third transmission surface for transmitting imaging light are sequentially arranged from outside to inside; on the second surface, a second transmission surface for transmitting illumination light and imaging light is arranged; on the inclined surface, a first reflection surface for totally reflecting illumination light is arranged; Wherein, the illumination light is incident on the first reflection surface through the first transmission surface and undergoes total reflection, then is incident on the second reflection surface and undergoes total reflection again, and then is incident on the second transmission surface. The imaging light is incident through the second transmission surface and exits through the third transmission surface to the objective lens group for imaging.

2. The endoscopic optical imaging system according to claim 1, wherein The illumination light incident into the waveguide lens through the first transmission surface is reflected to the second surface through the first reflection surface and the second reflection surface in sequence to form an illumination area. Among them, the illumination area is a simply connected area, and the second transmission surface is located within the illumination area.

3. The endoscopic optical imaging system according to claim 2, wherein The waveguide lens satisfies the following conditional formula: Wherein, φ is the illumination diameter formed by the first illumination beam or the second illumination beam on the second surface of the reference cross-section; L1 is the width of the first illumination beam or the second illumination beam; θ is the angle between the first surface of the optical waveguide lens and the inclined surface on the reference cross-section; The first illumination beam is the illumination light incident into the waveguide lens through the first reference incident surface, and the second illumination beam is the illumination light incident into the waveguide lens through the second reference incident surface. The first reference incident surface and the second reference incident surface are the first transmission surfaces of two opposite parts on the reference section, and the reference section is the plane obtained by intercepting the waveguide lens with a plane passing through the central axis of the waveguide lens.

4. The endoscopic optical imaging system according to claim 1, characterized in that The illumination light incident into the waveguide lens through the first transmission surface satisfies: The centers of the first illumination beam and the second illumination beam converge at the center of the second transmission surface, and the illumination diameters of the first illumination beam and the second illumination beam are both greater than or equal to the reference diameter of the second transmission surface; or, The adjacent edges of the first illumination beam and the second illumination beam converge at the center of the second transmission surface, and the illumination diameters of the first illumination beam and the second illumination beam are both greater than or equal to the reference radius of the second transmission surface; Wherein, the first illumination beam is the illumination light incident into the waveguide lens through the first reference incident surface, and the second illumination beam is the illumination light incident into the waveguide lens through the second reference incident surface. The first reference incident surface and the second reference incident surface are the first transmission surfaces of two opposite parts on the reference section, the reference diameter and the reference radius are respectively the diameter and the radius of the second transmission surface, and the reference section is the plane obtained by intercepting the waveguide lens with a plane passing through the central axis of the waveguide lens.

5. The endoscopic optical imaging system according to claim 4, characterized in that, The waveguide lens satisfies the following conditional formula: Wherein, L is the diameter of the first surface of the optical waveguide lens; L1 is the width of the first illumination beam or the second illumination beam; L2 is the distance from the center of the first illumination beam or the second illumination beam to the center of the optical waveguide lens; θ is the angle between the first surface of the optical waveguide lens and the inclined surface on the reference section; h 0 is the thickness of the optical waveguide lens; h 1 is the distance between the second surface of the optical waveguide lens and the object surface; n 0 is the refractive index of the optical waveguide lens; n 2 is the refractive index of the medium on the side of the second surface of the optical waveguide lens away from the optical waveguide lens.

6. The endoscopic optical imaging system according to claim 1, wherein The illumination light incident into the optical waveguide lens through the first transmission surface is reflected to the second transmission surface after undergoing one reflection on both the first reflection surface and the second reflection surface. The optical waveguide lens satisfies the following conditional formula: Wherein, L is the diameter of the first surface of the optical waveguide lens; L1 is the width of the first illumination beam or the second illumination beam; L2 is the distance from the center of the first illumination beam or the second illumination beam to the center of the optical waveguide lens; θ is the angle between the first surface of the optical waveguide lens and the inclined surface on the reference section; θ 2 is the incident angle θ 1 is the refraction angle of the illumination light incident on the optical waveguide lens from the first transmission surface; h 0 is the thickness of the optical waveguide lens; The first illumination beam is the illumination light incident into the optical waveguide lens through the first reference incident surface, and the second illumination beam is the illumination light incident into the optical waveguide lens through the second reference incident surface. The first reference incident surface and the second reference incident surface are the first transmission surfaces of two opposite parts on the reference cross-section, and the reference cross-section is the plane obtained by cutting the optical waveguide lens with a plane passing through the central axis of the optical waveguide lens.

7. The endoscopic optical imaging system according to claim 1, characterized in that, The first reflection surface and / or the second reflection surface is formed by setting a total reflection film; and / or, The optical waveguide lens satisfies the following conditional formula: Wherein, θ is the angle between the first surface of the optical waveguide lens and the inclined surface on the reference section; θ 2 is the refraction angle when the illumination light with an incident angle of θ 1 is incident from the first transmission surface to the optical waveguide lens; n 0 is the refractive index of the optical waveguide lens; n 1 is the refractive index of the medium on the side of the first surface of the optical waveguide lens away from the optical waveguide lens; n 2 is the refractive index of the medium on the side of the second surface of the optical waveguide lens away from the optical waveguide lens; The reference cross-section is the plane obtained by cutting the optical waveguide lens with a plane passing through the central axis of the optical waveguide lens.

8. The endoscopic optical imaging system according to claim 1, wherein, The optical waveguide lens satisfies the following conditional formula: Wherein, θ is the angle between the first surface of the optical waveguide lens and the inclined surface on the reference section; θ 1 is the incident angle of the illumination light incident from the first transmission surface; θ 2 is the refractive angle of the illumination light with an incident angle of θ 1 when it is incident from the first transmission surface to the optical waveguide lens; n 0 is the refractive index of the optical waveguide lens; n 1 is the refractive index of the medium on the side of the first surface of the optical waveguide lens away from the optical waveguide lens; n 2 is the refractive index of the medium on the side of the second surface of the optical waveguide lens away from the optical waveguide lens; The reference cross-section is the plane obtained by cutting the optical waveguide lens with a plane passing through the central axis of the optical waveguide lens.

9. The endoscopic optical imaging system according to claim 1, wherein The optical waveguide lens includes a first lens body, a second lens body, and a third lens body that are sleeved together from outside to inside in sequence; The first transmission surface and the first reflection surface are arranged on the first lens body, the second reflection surface is arranged on the second lens body, the second transmission surface is arranged on the third lens body, or the second lens body and the third lens body, and the third transmission surface is arranged on the third lens body.

10. The endoscopic optical imaging system according to claim 9, characterized in that, The first lens body, the second lens body, and the third lens body form the first surface on the first side surface in the axial direction of the optical waveguide lens; The second lens body and the third lens body form the second surface on the second side surface in the axial direction of the optical waveguide lens; The first lens body and the second lens body form the inclined surface on the outer peripheral side surface between the first surface and the second surface in the axial direction of the optical waveguide lens.

11. The endoscopic optical imaging system according to claim 9, wherein, The illumination light incident into the optical waveguide lens through the first transmission surface is 100% transmitted at the fitting interface between the first lens body and the second lens body and at the fitting interface between the second lens body and the third lens body.

12. The endoscopic optical imaging system according to claim 1, characterized in that, A collimating objective lens is installed between the light-emitting surface of the illumination optical fiber and the objective lens module, and the focus of the collimating objective lens is aligned with the light-emitting end face of the illumination optical fiber; and / or, The second surface of the optical waveguide lens is perpendicular to the axis of the internal lens sheath; and / or, The second surface of the optical waveguide lens is flush with the end face of the external lens sheath.

13. An endoscopic imaging system, characterized in that: An endoscopic optical imaging system according to any one of claims 1-12, wherein the endoscopic imaging system includes a photoelectric conversion module disposed inside the internal lens sheath and at the image distance position of the objective lens group for directly receiving imaging signals.

14. An endoscope device, characterized in that: An endoscopic optical imaging system according to any one of claims 1-12, wherein the endoscopic device comprises a light source for providing illumination light, an illumination optical fiber having one end connected to the light source and the other end extending and disposed inside an inner sheath and an outer sheath for transmitting the illumination light, a photoelectric conversion module disposed inside the inner sheath and at the image distance position of the objective lens group for receiving imaging signals, and a signal transmission line for transmitting the signals received by the photoelectric conversion module to a signal processing terminal.

15. The endoscope device according to claim 14, characterized in that: One of the light source and the signal processing terminal is provided with a connection end, and the connection end is integrated with an optical signal interface and an optoelectronic signal interface; the illumination optical fiber is connected to the light source through the optical signal interface, and the signal transmission line is connected to the signal processing terminal through the optoelectronic signal interface.

16. The endoscopic device according to claim 14, characterized in that: The endoscopic device comprises a handle, one end of the handle is connected to the outer sheath, and the other end is connected to the light source and the signal processing terminal through a wire harness, and the wire harness comprises the illumination optical fiber and the signal transmission line.

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