Endoscope optical module

Abstract

The invention discloses an endoscope optical module which comprises a left path optical module, a right path optical module, a reflection module, a first image sensor and a second image sensor which are arranged in an endoscope tube, left path incident light is reflected to the first image sensor through a left path reflection unit of the left path optical module and the reflection module, and right path incident light is reflected to the second image sensor through a right path reflection unit of the right path optical module. The right-path incident light is reflected to the second image sensor through the right-path reflection unit and the reflection module of the right-path optical module, and the arrangement direction of the left-path optical module and the right-path optical module intersects with the arrangement direction of the first image sensor and the second image sensor. According to the endoscope optical module provided by the embodiment of the invention, the left-path reflection unit, the right-path reflection unit and the reflection module are used for performing three-dimensional turning on the incident light, so that the image sensor can be attached to the inner wall of the endoscope tube, and therefore, the image sensor with a larger size can be placed in the endoscope tube, and higher-resolution imaging requirements can be met; and the 3D effect and the visible light and fluorescence imaging requirements can be met.

Description

Technical Field

[0001] The present invention relates to the technical field of endoscopes, and in particular to an endoscope optical module. Background Art

[0002] Nowadays, minimally invasive surgery has increasingly higher requirements for high-definition image quality. The ordinary 1080P resolution can no longer meet market demand. The resolution of the image sensor needs to reach 2K, 2.5K, or even 4K. The higher the resolution of the image sensor, the larger its size will be.

[0003] In addition, in abdominal surgery, traditional white light imaging lacks disease-specific optical features and cannot locate and visualize precancerous lesions, so the endoscope needs to have the function of fluorescence imaging. There are two main forms of implementation:

[0004] 1. The image sensor has the ability to simultaneously image white light and fluorescence. At the same resolution, the size of this image sensor will be larger.

[0005] 2. Through the spectroscopic structure, the white light image sensor and the fluorescence image sensor are used to image white light and fluorescence respectively, which will increase the number of image sensors and thus increase the overall volume.

[0006] At the same time, robotic surgery requires that the diameter of the medical rigid endoscope tube used is no more than 10mm, and the same two-way optical system needs to be placed in the tube to enable three-dimensional (3D) imaging through the principle of binocular stereo vision. Therefore, the conventional structure cannot meet the requirements due to the large size of the image sensor.

[0007] Based on the above limitations, most rigid endoscopes on the market cannot meet the following three requirements at the same time:

[0008] 1. Higher definition picture quality above 1080P.

[0009] 2. White light and fluorescence superposition imaging.

[0010] 3. Realize binocular 3D vision in 10mm mirror tube.

[0011] Common rigid endoscopes can only meet the above two requirements at most. Summary of the invention

[0012] The present invention provides an endoscope optical module to solve the problem that the endoscope tube cannot accommodate an image sensor, thereby being able to simultaneously achieve the requirements of high-definition image quality, white light and fluorescence superposition imaging, and binocular 3D vision.

[0013] The present invention provides an endoscope optical module, comprising a mirror tube and a left optical module, a right optical module, a reflection module, a first image sensor and a second image sensor arranged in the mirror tube;

[0014] The left optical module and the right optical module are respectively located on opposite sides of the central axis of the mirror tube;

[0015] The left optical module comprises a left optical lens group and a left reflective unit arranged along the propagation direction of the incident light, and the left incident light received by the left optical lens group is reflected to the reflective module by the left reflective unit;

[0016] The right optical module comprises a right optical lens group and a right reflection unit arranged along the propagation direction of the incident light, and the right incident light received by the right optical lens group is reflected to the reflection module by the right reflection unit;

[0017] The first image sensor and the second image sensor are respectively located on opposite sides of the central axis of the mirror tube; the left-path incident light is reflected by the reflection module to the first image sensor, and the right-path incident light is reflected by the reflection module to the second image sensor;

[0018] The arrangement direction of the left optical module and the right optical module is a first direction, and the arrangement direction of the first image sensor and the second image sensor is a second direction, wherein the first direction and the second direction intersect.

[0019] Optionally, an extension direction of a short side of the first image sensor intersects with an extension direction of a central axis of the mirror tube;

[0020] An extension direction of a short side of the second image sensor intersects with an extension direction of a central axis of the mirror tube.

[0021] Optionally, the angle between the optical axis direction of the left optical lens group and the reflection surface of the left reflection unit is θ1, wherein 40°≤θ1≤50°;

[0022] The angle between the optical axis direction of the right optical lens group and the reflecting surface of the right reflecting unit is θ2, wherein 40°≤θ2≤50°.

[0023] Optionally, the angle between the first direction and the second direction is θ, where 80°≤θ≤100°.

[0024] Optionally, the shortest distance between the optical axis of the left optical lens group and the optical axis of the right optical lens group is d1, where d1≥4mm.

[0025] Optionally, the left optical lens group includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens and a seventh lens arranged in sequence along the propagation direction of the incident light;

[0026] The first lens has negative optical power, and the second lens has positive optical power;

[0027] The third lens has positive optical power, and the fourth lens has negative optical power; or, the third lens has negative optical power, and the fourth lens has positive optical power;

[0028] The sixth lens has positive optical power, and the seventh lens has negative optical power; or, the sixth lens has negative optical power, and the seventh lens has positive optical power;

[0029] The right optical lens group and the left optical lens group have the same structure.

[0030] Optionally, the refractive index of the third lens is Nd3, and the Abbe number of the third lens is Vd3; the refractive index of the fourth lens is Nd4, and the Abbe number of the fourth lens is Vd4; the refractive index of the sixth lens is Nd6, and the Abbe number of the sixth lens is Vd6; the refractive index of the seventh lens is Nd7, and the Abbe number of the seventh lens is Vd7; wherein,

[0031] 1.5 <Nd3<1.7,45<Vd3<66;1.7<Nd4<1.8,35<Vd4<50;

[0032] 1.5 <Nd6<1.7,45<Vd6<65;1.8<Nd7<1.9,25<Vd7<40。

[0033] Optionally, the third lens and the fourth lens form a cemented lens group;

[0034] and / or,

[0035] The sixth lens and the seventh lens form a cemented lens group.

[0036] Optionally, the second lens is a turning prism.

[0037] Optionally, the left optical module further includes an eighth lens, and the eighth lens is located in the optical path between the seventh lens and the left reflection unit, or the eighth lens is located in the optical path between the reflection module and the first image sensor;

[0038] The right optical module and the left optical module have the same structure, and the right optical module and the left optical module are symmetrically arranged relative to the central axis of the mirror tube.

[0039] The endoscope optical module provided by the embodiment of the present invention comprises a left optical module, a right optical module, a reflection module, a first image sensor and a second image sensor arranged in a mirror tube, the left optical module and the right optical module are respectively located on opposite sides of the central axis of the mirror tube, the left optical module comprises a left optical lens group and a left reflection unit arranged along the propagation direction of the incident light, the left incident light received by the left optical lens group is reflected to the reflection module via the left reflection unit, the right optical module comprises a right optical lens group and a right reflection unit arranged along the propagation direction of the incident light, the right incident light received by the right optical lens group is reflected to the reflection module via the right reflection unit. The first image sensor and the second image sensor are respectively located on opposite sides of the central axis of the mirror tube, the left incident light is reflected to the first image sensor via the reflection module, and the right incident light is reflected to the second image sensor via the reflection module. Among them, by setting the arrangement direction of the left optical module and the right optical module to intersect with the arrangement direction of the first image sensor and the second image sensor, the left incident light and the right incident light are folded twice by using the left reflection unit, the right reflection unit and the reflection module, so as to realize the three-dimensional folding of the left incident light and the right incident light in the mirror tube. In this way, the first image sensor and the second image sensor can be arranged close to the inner wall of the mirror tube. Compared with placing two image sensors side by side behind two optical modules, when the diameter of the mirror tube remains unchanged, the endoscope optical module structure provided by the embodiment of the present invention can place a larger first image sensor and a second image sensor in the mirror tube, thereby meeting the demand for higher resolution imaging, and is conducive to simultaneously meeting the needs of real 3D effects and visible light and fluorescence imaging, solving the problem that the existing endoscope optical module structure cannot accommodate image sensors in the mirror tube.

[0040] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0042] Figure 1 A schematic diagram of a top view of an endoscope optical module provided by an embodiment of the present invention;

[0043] Figure 2 A schematic diagram of the side structure of an endoscope optical module provided by an embodiment of the present invention;

[0044] Figure 3 A schematic diagram of the front view structure of an endoscope optical module provided by an embodiment of the present invention;

[0045] Figure 4 A schematic diagram of the optical path of an endoscope optical module provided by an embodiment of the present invention;

[0046] Figure 5 A schematic structural diagram of a reflective prism provided by an embodiment of the present invention;

[0047] Figure 6 A schematic structural diagram of a right-angle reflection prism provided by an embodiment of the present invention;

[0048] Figure 7 A schematic structural diagram of a plane reflector provided in an embodiment of the present invention;

[0049] Figure 8 A schematic diagram of the combined structure of a reflective prism provided by an embodiment of the present invention;

[0050] Fig. 9 A schematic front view of the structure of another endoscope optical module provided by an embodiment of the present invention;

[0051] Fig.10 A front view structural schematic diagram of another endoscope optical module provided by an embodiment of the present invention;

[0052] Fig.11 A schematic diagram of the structure of a left optical module provided by an embodiment of the present invention;

[0053] Fig.12 A chromatic aberration curve diagram of an endoscope optical module provided by an embodiment of the present invention;

[0054] Fig.13 A field curvature and distortion curve diagram of an endoscope optical module provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0055] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0056] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0057] Figure 1 A schematic diagram of a top view of an endoscope optical module provided by an embodiment of the present invention, Figure 2 A schematic diagram of a side view structure of an endoscope optical module provided by an embodiment of the present invention, Figure 3 A schematic diagram of the front view structure of an endoscope optical module provided by an embodiment of the present invention, Figure 4 A schematic diagram of an optical path of an endoscope optical module provided by an embodiment of the present invention, such as Figure 1-Figure 4 As shown, the endoscope optical module provided by the embodiment of the present invention includes a mirror tube 10 and a left optical module 11, a right optical module 12, a reflection module 13, a first image sensor 14, and a second image sensor 15 arranged in the mirror tube 10. The left optical module 11 and the right optical module 12 are respectively located on opposite sides of the central axis 20 of the mirror tube 10, and the left optical module 11 includes a left optical lens group 111 and a left reflection unit 112 arranged along the propagation direction of the incident light, and the left incident light 21 received by the left optical lens group 111 is reflected to the reflection module 13 through the left reflection unit 112; the right optical module 12 includes a right optical lens group 121 and a right reflection unit 122 arranged along the propagation direction of the incident light, and the right incident light 22 received by the right optical lens group 121 is reflected to the reflection module 13 through the right reflection unit 122. The first image sensor 14 and the second image sensor 15 are respectively located on opposite sides of the central axis 20 of the mirror tube 10. The left incident light 21 is reflected to the first image sensor 14 by the reflection module 13, and the right incident light 22 is reflected to the second image sensor 15 by the reflection module 13. The arrangement direction of the left optical module 11 and the right optical module 12 is the first direction X, and the arrangement direction of the first image sensor 14 and the second image sensor 15 is the second direction Y, wherein the first direction X and the second direction Y intersect.

[0058] Specifically, the endoscope optical module provided in the embodiment of the present invention may be a 3D rigid endoscope optical module used for photographing images inside a patient's body during a surgical operation.

[0059] Among them, a left optical module 11 and a right optical module 12 are installed inside the mirror tube 10 of the endoscope optical module. The left optical module 11 can include multiple optical elements. Similarly, the right optical module 12 can also include multiple optical elements. The structures of the left optical module 11 and the right optical module 12 can be exactly the same. The left optical module 11 and the right optical module 12 can be symmetrically arranged relative to the central axis 20 of the mirror tube 10. In this way, the consistency of left and right imaging can be ensured, and the difference in brightness, contrast and color between the left image and the right image can be reduced, which is conducive to obtaining high-quality three-dimensional images.

[0060] At the same time, the optical axes of the left optical module 11 and the right optical module 12 can be arranged parallel to the central axis 20 of the mirror tube 10, which helps to provide sufficient placement space for other devices.

[0061] It should be noted that the extension direction of the central axis 20 of the mirror tube 10 is parallel to the extension direction of the mirror tube 10 .

[0062] Continue to refer Figure 1-Figure 4 The left optical module 11 includes a left optical lens group 111 and a left reflection unit 112. The left optical lens group 111 may be provided with a plurality of optical lenses to form a left lens. The left reflection unit 112 is used to fold the left incident light 21 received by the left optical lens group 111, that is, after the left incident light 21 passes through the left optical lens group 111, the propagation direction of the left incident light 21 is changed by the left reflection unit 112 to reflect the left incident light 21 to the reflection module 13; Similarly, the right optical module 12 includes a right optical lens group 121 and a right reflection unit 122. A plurality of optical lenses may be provided in the right optical lens group 121 to form a right lens. The right reflection unit 122 is used to fold the right incident light 22 received by the right optical lens group 121, that is, after the right incident light 22 passes through the right optical lens group 121, the propagation direction of the right incident light 22 is changed by the right reflection unit 122 to reflect the right incident light 22 to the reflection module 13.

[0063] Among them, Figure 1-Figure 4 As shown, the reflection module 13 can be arranged between the left reflection unit 112 and the right reflection unit 122. The reflection module 13 is used to redirect the left-path incident light 21 reflected by the left reflection unit 112 to the first image sensor 14, and to redirect the right-path incident light 22 reflected by the right reflection unit 122 to the second image sensor 15. In this way, the first image sensor 14 receives the left-path incident light 21 and can convert the left-path incident light 21 into a first electrical signal; the second image sensor 15 receives the right-path incident light 22 and can convert the right-path incident light 22 into a second electrical signal.

[0064] Furthermore, a left image can be obtained through a first electrical signal output by the first image sensor 14, and a right image can be obtained through a second electrical signal output by the second image sensor 15. The left image and the right image are images obtained by imaging the subject from different angles at the same time. Therefore, the pictures of the left image and the right image are different. By fusing the left image and the right image, a 3D effect can be formed to obtain a 3D image.

[0065] The first image sensor 14 and the second image sensor 15 may include at least one of a complementary metal oxide semiconductor (CMOS) device and a charge-coupled device (CCD), but are not limited thereto. At the same time, the first image sensor 14 and the second image sensor 15 may simultaneously image visible light and fluorescence, or may independently image visible light or fluorescence, which is not specifically limited in the embodiment of the present invention.

[0066] It should be noted that the left optical module 11 and the right optical module 12 share the same reflection module 13, that is, one reflection module 13 is used to simultaneously reflect the left incident light 21 transmitted by the left optical module 11 to the first image sensor 14, and to reflect the right incident light 22 transmitted by the right optical module 12 to the second image sensor 15. In this way, the first image sensor 14 can receive the left incident light 21, and the second image sensor 15 can receive the right incident light 22 with a minimum of reflection structures.

[0067] Further, continue to refer to Figure 1-Figure 4 The reflection module 13 can be arranged on the central axis 20 of the mirror tube 10 . Such an arrangement can provide sufficient arrangement space for the first image sensor 14 and the second image sensor 15 .

[0068] In the embodiment of the present invention, Figure 1-Figure 4As shown, the arrangement direction of the left optical module 11 and the right optical module 12 (for example, the first direction X in the figure) intersects with the arrangement direction of the first image sensor 14 and the second image sensor 15 (for example, the second direction Y in the figure), and the left reflection unit 112, the right reflection unit 122 and the reflection module 13 are used to fold the left incident light 21 and the right incident light 22 twice, so as to realize the three-dimensional folding of the left incident light 21 and the right incident light 22 in the mirror tube 10. In this way, the first image sensor 14 and the second image sensor 15 can be arranged on the inner wall of the mirror tube 10. Compared with the two image sensors placed side by side behind the two optical modules (the photosensitive surface of the image sensor is perpendicular to the central axis of the mirror tube), in the endoscope optical module provided by the embodiment of the present invention, when the diameter of the mirror tube 10 remains unchanged, the first image sensor 14 and the second image sensor 15 of larger size can be placed in the mirror tube 10, thereby meeting the demand for higher resolution imaging, and being conducive to simultaneously meeting the needs of real 3D effect and visible light and fluorescence imaging.

[0069] Exemplarily, taking an image sensor with a resolution of 2.5K and capable of achieving superimposed imaging of visible light and fluorescence as an example, the size of the image sensor is often 1 / 3 inch or more. For example, when the length of the image sensor is 6.35 mm and the width is 4 mm, if two 2.5K image sensors are placed side by side behind two optical modules, a mirror tube with a diameter of 10 mm cannot accommodate the two 2.5K image sensors. In this structure, the mirror tube needs to have a diameter of at least 12.7 mm. In the endoscope optical module structure provided in an embodiment of the present invention, the placement of the two 2.5K image sensors mentioned above can be achieved in a mirror tube with a diameter of 10 mm, thereby achieving high-resolution 3D imaging effects under visible light and fluorescence in a mirror tube with a diameter of 10 mm.

[0070] Continue to refer Figure 1-Figure 4 Optionally, the first image sensor 14 and the second image sensor 15 are symmetrically arranged relative to the central axis 20 of the mirror tube 10, which can improve the consistency of the left image and the right image and help obtain a high-quality three-dimensional image.

[0071] In summary, the endoscope optical module provided by the embodiment of the present invention is provided with a left optical module, a right optical module, a reflection module, a first image sensor and a second image sensor in the mirror tube, the left optical module and the right optical module are respectively located on opposite sides of the central axis of the mirror tube, the left optical module includes a left optical lens group and a left reflection unit arranged along the propagation direction of the incident light, the left incident light received by the left optical lens group is reflected to the reflection module via the left reflection unit, the right optical module includes a right optical lens group and a right reflection unit arranged along the propagation direction of the incident light, the right incident light received by the right optical lens group is reflected to the reflection module via the right reflection unit. The first image sensor and the second image sensor are respectively located on opposite sides of the central axis of the mirror tube, the left incident light is reflected to the first image sensor via the reflection module, and the right incident light is reflected to the second image sensor via the reflection module. Among them, by setting the arrangement direction of the left optical module and the right optical module to intersect with the arrangement direction of the first image sensor and the second image sensor, the left incident light and the right incident light are folded twice by using the left reflection unit, the right reflection unit and the reflection module, so as to realize the three-dimensional folding of the left incident light and the right incident light in the mirror tube. In this way, the first image sensor and the second image sensor can be arranged close to the inner wall of the mirror tube. Compared with placing two image sensors side by side behind two optical modules, when the diameter of the mirror tube remains unchanged, the endoscope optical module structure provided by the embodiment of the present invention can place a larger first image sensor and a second image sensor in the mirror tube, thereby meeting the demand for higher resolution imaging, and is conducive to simultaneously meeting the needs of real 3D effects and visible light and fluorescence imaging, solving the problem that the existing endoscope optical module structure cannot accommodate image sensors in the mirror tube.

[0072] Continue to refer Figure 1-Figure 4 Optionally, the short side extending direction of the first image sensor 14 intersects with the extending direction of the central axis 20 of the mirror tube 10 , and the short side extending direction of the second image sensor 15 intersects with the extending direction of the central axis 20 of the mirror tube 10 .

[0073] The short side of the image sensor refers to the side with a shorter length at the edge of the image sensor, and the long side of the image sensor refers to the side with a longer length at the edge of the image sensor. Taking the image sensor as a rectangle as an example, the image sensor includes two opposite short sides and two opposite long sides.

[0074] In this embodiment, if Figure 1-Figure 4As shown, by setting the short sides of the first image sensor 14 and the second image sensor 15 to extend in a direction that intersects with the extension direction of the central axis 20 of the mirror tube 10, that is, the short sides of the first image sensor 14 and the second image sensor 15 are placed opposite to the extension direction of the mirror tube 10, so that the length of the first image sensor 14 in the direction perpendicular to the central axis 20 is smaller than the length of the first image sensor 14 in the extension direction of the central axis 20. Similarly, the length of the second image sensor 15 in the direction perpendicular to the central axis 20 is smaller than the length of the second image sensor 15 in the extension direction of the central axis 20. In this way, the distance between the first image sensor 14 and the inner wall of the mirror tube 10, as well as the distance between the second image sensor 15 and the inner wall of the mirror tube 10 can be smaller, thereby leaving a larger placement space for the left optical module 11, the right optical module 12 and the reflection module 13, thereby improving space utilization.

[0075] Further, continue to refer to Figure 1-Figure 4 , the short sides of the first image sensor 14 and the second image sensor 15 can be arranged to extend in a direction perpendicular to the extension direction of the central axis 20 of the mirror tube 10, that is, the short sides of the first image sensor 14 and the second image sensor 15 are placed opposite to the extension direction of the mirror tube 10. At this time, the long sides of the first image sensor 14 and the second image sensor 15 can extend in a direction parallel to the extension direction of the central axis 20 of the mirror tube 10, so that the length of the first image sensor 14 in the direction perpendicular to the central axis 20 can be minimized, and similarly, the length of the second image sensor 15 in the direction perpendicular to the central axis 20 can also be minimized, so that the distance between the first image sensor 14 and the inner wall of the mirror tube 10, and the distance between the second image sensor 15 and the inner wall of the mirror tube 10 can be minimized, thereby leaving more sufficient placement space for the left optical module 11, the right optical module 12 and the reflection module 13, further improving space utilization.

[0076] Continue to refer Figure 1-Figure 4 Optionally, the angle between the optical axis direction of the left optical lens group 111 and the reflecting surface of the left reflecting unit 112 is θ1, wherein 40°≤θ1≤50°, and the angle between the optical axis direction of the right optical lens group 121 and the reflecting surface of the right reflecting unit 122 is θ2, wherein 40°≤θ2≤50°.

[0077] Among them, by setting the angle θ1 between the optical axis direction of the left optical lens group 111 and the reflecting surface of the left reflection unit 112 to satisfy 40°≤θ1≤50°, the angle at which the left reflection unit 112 refracts the left incident light 21 received by the left optical lens group 111 is 80°~100°. Similarly, the angle θ2 between the optical axis direction of the right optical lens group 121 and the reflecting surface of the right reflection unit 122 satisfies 40°≤θ2≤50°, so that the angle at which the right reflection unit 122 refracts the right incident light 22 received by the right optical lens group 121 is 80°~100°. In this way, the reflection module 13 can be set between the left reflection unit 112 and the right reflection unit 122, so that the structures of the left optical module 11, the right optical module 12 and the reflection module 13 can be relatively compact in the extension direction of the central axis 20 of the mirror tube 10, thereby improving space utilization.

[0078] Furthermore, if Figure 1-Figure 4 As shown, the angle θ1 between the optical axis direction of the left optical lens group 111 and the reflecting surface of the left reflecting unit 112 can be set to 45°, so that the left reflecting unit 112 can be bent 90° for the left incident light 21 received by the left optical lens group 111. Similarly, the angle θ2 between the optical axis direction of the right optical lens group 121 and the reflecting surface of the right reflecting unit 122 is 45°, so that the right reflecting unit 122 can be bent 90° for the right incident light 22 received by the right optical lens group 121. In this way, the reflecting module 13 is arranged between the left reflecting unit 112 and the right reflecting unit 122, and can be arranged in the extension direction of the central axis 20 of the mirror tube 10, so that the structures of the left optical module 11, the right optical module 12 and the reflecting module 13 are more compact, and the space in the mirror tube 10 is fully utilized, thereby further improving the space utilization rate.

[0079] Continue to refer Figure 1-Figure 4 Optionally, the angle between the first direction X and the second direction Y is θ, where 80°≤θ≤100°.

[0080] Specifically, Figure 1-Figure 4As shown, the angle θ between the first direction X and the second direction Y satisfies 80°≤θ≤100°. At this time, the angle between the propagation direction of the left-path incident light 21 reflected by the left-path reflection unit 112 and the reflection surface of the reflection module 13 is 40°~50°, so that the deflection angle of the left-path incident light 21 by the reflection module 13 is 80°~100°; similarly, the angle between the propagation direction of the right-path incident light 22 reflected by the right-path optical lens group 121 and the reflection surface of the reflection module 13 is 40°~50°, so that the deflection angle of the right-path incident light 22 by the reflection module 13 is 80°~100°. In this way, the first image sensor 14 and the second image sensor 15 can be arranged on opposite sides of the reflection module 13. At this time, the left reflection unit 112, the right reflection unit 122, the first image sensor 14 and the second image sensor 15 are arranged around the reflection module 13, in the extension direction of the central axis 20 of the mirror tube 10, so that the spatial arrangement of the left optical module 11, the right optical module 12, the first image sensor 14, the second image sensor 15 and the reflection module 13 is relatively compact, thereby improving space utilization.

[0081] Furthermore, if Figure 1-Figure 4 As shown, the angle θ between the first direction X and the second direction Y can be set to 90°. At this time, the angle between the propagation direction of the left-path incident light 21 reflected by the left-path reflection unit 112 and the reflection surface of the reflection module 13 is 45°, so that the deflection angle of the left-path incident light 21 by the reflection module 13 is 90°; similarly, the angle between the propagation direction of the right-path incident light 22 reflected by the right-path optical lens group 121 and the reflection surface of the reflection module 13 is 45°, so that the deflection angle of the right-path incident light 22 by the reflection module 13 is 90°. In this arrangement, the first image sensor 14 and the second image sensor 15 are arranged on opposite sides of the reflection module 13, and the left reflection unit 112, the right reflection unit 122, the first image sensor 14 and the second image sensor 15 are arranged around the reflection module 13, in the extension direction of the central axis 20 of the mirror tube 10, so that the spatial arrangement of the left optical module 11, the right optical module 12, the first image sensor 14, the second image sensor 15 and the reflection module 13 is more compact, which can further improve the space utilization.

[0082] Continue to refer Figure 1-Figure 4 Optionally, the photosensitive surface of the first image sensor 14 and the photosensitive surface of the second image sensor 15 are arranged parallel to the central axis 20 of the mirror tube 10. This can leave more placement space for the left optical module 11, the right optical module 12 and the reflection module 13, improve space utilization, and at the same time, it is also beneficial to reduce the assembly error of the first image sensor 14 and the second image sensor 15.

[0083] Figure 5A schematic diagram of the structure of a reflective prism provided by an embodiment of the present invention, Figure 6 A schematic diagram of the structure of a right-angle reflection prism provided in an embodiment of the present invention, Figure 7 A schematic diagram of the structure of a plane reflector provided by an embodiment of the present invention is shown in FIG. Figure 1-Figure 7 As shown, optionally, the left-path reflection unit 112 may include any one of a reflection prism, a right-angle reflection prism and a plane reflector, the right-path reflection unit 122 may include any one of a reflection prism, a right-angle reflection prism and a plane reflector, and the reflection module 13 may also include any one of a reflection prism, a right-angle reflection prism and a plane reflector.

[0084] For example, Figure 4 As shown, the left-path reflection unit 112, the right-path reflection unit 122 and the reflection module 13 can all use a reflection prism, and the reflection prism has many positioning surfaces, so when assembling the left-path reflection unit 112, the right-path reflection unit 122 and the reflection module 13, the positioning accuracy can be improved, which helps to obtain a high-quality three-dimensional image. At the same time, the reflection surface of the reflection prism is located inside the reflection prism, which can reduce the risk of the reflection surface falling off and increase the service life of the endoscope optical module, but is not limited to this.

[0085] Figure 8 A schematic diagram of a combined structure of a reflective prism provided in an embodiment of the present invention, such as Figure 4 and Figure 8 As shown, when the reflection module 13 is a reflection prism, the reflection prism can be composed of two right-angle reflection prisms, which can reduce the difficulty of manufacturing the reflection prism. The reflection surfaces of the two right-angle reflection prisms fit together, which is beneficial to reducing the occupied space of the reflection module 13 and improving the space utilization inside the mirror tube 10.

[0086] Fig. 9 A schematic diagram of the front view structure of another endoscope optical module provided by an embodiment of the present invention is shown in FIG. Fig. 9 As shown, optionally, the reflection module 13 may also adopt a plane reflector, and the plane reflector may have a thinner thickness (eg, about 0.5 mm), which helps to reduce the weight of the endoscope optical module.

[0087] It should be noted that the surface reflectivity of the reflecting surfaces of the left-path reflecting unit 112, the right-path reflecting unit 122 and the reflecting module 13 can be greater than or equal to 70%, so as to ensure the reflection efficiency of the left-path reflecting unit 112, the right-path reflecting unit 122 and the reflecting module 13, which is conducive to improving the imaging quality.

[0088] Fig.10 A front view structural diagram of another endoscope optical module provided in an embodiment of the present invention is shown in FIG. Fig. 9 and Fig.10As shown, the reflective surface of the reflective module 13 can be flipped according to design requirements. According to the setting direction of the reflective surface of the reflective module 13, the first image sensor 14 corresponding to the left optical module 11 and the second image sensor 15 corresponding to the right optical module 12 can be interchanged. Those skilled in the art can make settings according to actual needs.

[0089] Continue to refer Figure 1-Figure 4 Optionally, the shortest distance between the optical axis of the left optical lens group 111 and the optical axis of the right optical lens group 121 is d1, where d1≥4mm.

[0090] Among them, by setting the shortest distance d1 between the optical axis of the left optical lens group 111 and the optical axis of the right optical lens group 121 to be not less than 4 mm, on the one hand, sufficient setting space can be provided for the reflection module 13, and on the other hand, the 3D imaging effect can be made close to the real observation effect of the human eye (the pupil distance of the human eye is generally around 63 mm), thereby making the 3D imaging effect more realistic and reducing the risk of dizziness.

[0091] Fig.11 A schematic diagram of the structure of a left optical module provided by an embodiment of the present invention is shown in FIG. Figure 1-Figure 4 , Fig.11 As shown, optionally, the left optical lens group 111 includes a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6 and a seventh lens L7 arranged in sequence along the propagation direction of the incident light. The first lens L1 has a negative focal power, and the second lens L2 has a positive focal power; the third lens L3 has a positive focal power, and the fourth lens L4 has a negative focal power; or, the third lens L3 has a negative focal power, and the fourth lens L4 has a positive focal power; the sixth lens L6 has a positive focal power, and the seventh lens L7 has a negative focal power; or, the sixth lens L6 has a negative focal power, and the seventh lens L7 has a positive focal power. The right optical lens group 121 and the left optical lens group 111 have the same structure.

[0092] Among them, the focal length is equal to the difference between the convergence of the image-side light beam and the convergence of the object-side light beam, and it characterizes the ability of the optical system to deflect light. The larger the absolute value of the focal length, the stronger the ability to bend light, and the smaller the absolute value of the focal length, the weaker the ability to bend light. When the focal length is a positive number, the refraction of light is convergent; when the focal length is a negative number, the refraction of light is divergent. The focal length can be used to characterize a certain refractive surface of a lens (i.e., a surface of a lens), can be used to characterize a certain lens, and can also be used to characterize a system formed by multiple lenses (i.e., a lens group).

[0093] In the embodiment of the present invention, the right optical lens group 121 and the left optical lens group 111 are arranged to have the same structure, which can ensure the consistency of left and right imaging, reduce the difference in brightness, contrast, color, etc. between the left image and the right image, and is conducive to obtaining high-quality three-dimensional images.

[0094] Among them, by setting the optical focal length of the first lens L1 to be negative and the optical focal length of the second lens L2 to be positive, the field of view angle FOV of the left optical module 11 and the right optical module 12 can satisfy FOV≥75°, thereby providing a sufficient field of view. At the same time, the size of the lenses used in the left optical lens group 111 and the right optical lens group 121 can also be reduced.

[0095] Furthermore, setting the third lens L3 and the fourth lens L4 to have opposite refractive powers, and setting the sixth lens L6 and the seventh lens L7 to have opposite refractive powers is beneficial to reducing aberrations.

[0096] Furthermore, by reasonably setting the number of lenses in the left optical lens group 111 and the right optical lens group 121 and matching the optical power of each lens, the aberration can be reduced, and a better imaging effect can be achieved, which is conducive to obtaining high-quality three-dimensional images.

[0097] Exemplarily, the third lens L3 has positive focal power, the fourth lens L4 has negative focal power, the sixth lens L6 has positive focal power, and the seventh lens L7 has negative focal power is taken as an example for explanation, wherein the first lens L1 has negative focal power, the second lens L2 has positive focal power, the third lens L3 has positive focal power, the fourth lens L4 has negative focal power, the fifth lens L5 has negative focal power, the sixth lens L6 has positive focal power, and the seventh lens L7 has negative focal power. Such an arrangement can greatly reduce aberrations and obtain better imaging effects.

[0098] Continue to refer Fig.11 Optionally, the refractive index of the third lens L3 is Nd3, and the Abbe number of the third lens L3 is Vd3; the refractive index of the fourth lens L4 is Nd4, and the Abbe number of the fourth lens L4 is Vd4; the refractive index of the sixth lens L6 is Nd6, and the Abbe number of the sixth lens L6 is Vd6; the refractive index of the seventh lens L7 is Nd7, and the Abbe number of the seventh lens L7 is Vd7; wherein,

[0099] 1.5 <Nd3<1.7,45<Vd3<66;1.7<Nd4<1.8,35<Vd4<50;

[0100] 1.5 <Nd6<1.7,45<Vd6<65;1.8<Nd7<1.9,25<Vd7<40。

[0101] Among them, the refractive index is the ratio of the speed of light in a vacuum to the speed of light in the medium, which is mainly used to describe the refraction ability of the material to light. Different materials have different refractive indices.

[0102] The Abbe number is an index used to represent the dispersion ability of a transparent medium. The more severe the dispersion of the medium, the smaller the Abbe number; conversely, the milder the dispersion of the medium, the larger the Abbe number.

[0103] In this embodiment, by reasonably setting the refractive indices and Abbe numbers of the third lens L3 and the fourth lens L4, and matching the power distribution of the third lens L3 and the fourth lens L4, chromatic aberration can be effectively improved.

[0104] At the same time, by reasonably setting the refractive indices and Abbe numbers of the sixth lens L6 and the seventh lens L7, and matching the power distribution of the sixth lens L6 and the seventh lens L7, chromatic aberration and distortion can be effectively improved.

[0105] Furthermore, by reasonably setting the refractive indices and Abbe numbers of each lens in the left optical lens group 111 and the right optical lens group 121, chromatic aberration and distortion can be further reduced to achieve a better imaging effect and obtain a high-quality three-dimensional image.

[0106] Exemplarily, the refractive index of the first lens L1 is Nd1, and the Abbe number of the first lens L1 is Vd1; the refractive index of the second lens L2 is Nd2, and the Abbe number of the second lens L2 is Vd2; the refractive index of the fifth lens L5 is Nd5, and the Abbe number of the fifth lens L5 is Vd5; among them, 1.8 < Nd1 < 1.9, 35 < Vd1 < 50; 1.7 < Nd2 < 1.85, 35 < Vd2 < 50; 1.8 < Nd5 < 2.0, 20 < Vd5 < 35. With such settings, chromatic aberration and distortion can be significantly reduced to obtain a better imaging effect.

[0107] Continue to refer to Fig.11 , optionally, the third lens L3 and the fourth lens L4 form a cemented lens group; and / or, the sixth lens L6 and the seventh lens L7 form a cemented lens group.

[0108] Among them, by setting the third lens L3 and the fourth lens L4 to form a cemented lens group, the primary chromatic aberration of the optical system can be effectively corrected. At the same time, by setting the sixth lens L6 and the seventh lens L7 to form a cemented lens group, the axial chromatic aberration and lateral chromatic aberration of the system can be effectively corrected, thereby obtaining a better imaging effect.

[0109] In addition, by reasonably arranging the positions of the cemented lens groups, while maintaining the field of view FOV of the left optical module 11 and the right optical module 12 satisfying FOV ≥ 75°, the sizes of the lenses used in the left optical lens group 111 and the right optical lens group 121 can be further reduced.

[0110] Continue to refer to Fig.11 , optionally, the second lens L2 is a turning prism.

[0111] Among them, the turning prism can be an optical element or a combination of multiple optical elements. The turning prism can change the direction of the optical path based on principles such as reflection or refraction. By setting the second lens L2 as the turning prism, the endoscope optical module can adapt to different usage scenarios. For example, in some embodiments, the turning prism can change the optical path by 30°, so that the endoscope optical module can be applied to application scenarios with a viewing angle of 30°, making the viewing direction of the endoscope optical module inclined to the extension direction of the lens tube, so as to adapt to different diagnostic requirements. Of course, according to different diagnostic requirements, the turning prism can also be set to be able to change the optical path by any other angle, including but not limited to 10°, 20°, 45°, 60°, etc., and the embodiments of the present invention do not make specific limitations on this.

[0112] Furthermore, set the central thickness of the second lens L2 to be greater than or equal to 4 mm, which helps the second lens L2 to meet the turning requirements of different viewing angles.

[0113] Continue to refer to Fig.11 , optionally, the left optical module 11 further includes an eighth lens L8, and the eighth lens L8 is located in the optical path between the seventh lens L7 and the left reflection unit 112, or the eighth lens L8 is located in the optical path between the reflection module 13 and the first image sensor 14; the right optical module 12 and the left optical module 11 have the same structure, and the right optical module 12 and the left optical module 11 are symmetrically arranged with respect to the central axis 20 of the lens tube 10.

[0114] Among them, as Fig.11 shown, taking the eighth lens L8 of the left optical module 11 being located in the optical path between the reflection module 13 and the first image sensor 14, and the eighth lens L8 of the right optical module 12 being located in the optical path between the reflection module 13 and the second image sensor 15 as an example for illustration, the eighth lens L8 can reduce the principal ray angle, making the matching of the principal ray angle between the left optical module 11 and the first image sensor 14 better, and the matching of the principal ray angle between the right optical module 12 and the second image sensor 15 better, which helps to improve the imaging quality.

[0115] Furthermore, the eighth lens L8 can have a negative optical power. At the same time, the refractive index of the eighth lens L8 is Nd8, and the Abbe number of the eighth lens L8 is Vd8. Among them, 1.6 < Nd8 < 1.8, 35 < Vd8 < 60. Such a setting helps to reduce aberration and achieve a better imaging effect.

[0116] In other embodiments, the eighth lens L8 may also be located in the optical path between the seventh lens L7 and the left path reflection unit 112, and the embodiments of the present invention do not make specific limitations thereto.

[0117] Continuing to refer to Fig.11 , the left path optical module 11 further includes a protective glass L0, and the protective glass L0 is located on the side of the first lens L1 facing away from the second lens L2 to protect the optical lens group and improve the service life of the endoscope optical module.

[0118] It should be noted that the above-mentioned various lenses may all be made of glass materials to meet the requirements of high-temperature sterilization.

[0119] In addition, the surface types of the above-mentioned various lenses may be spherical surfaces, aspherical surfaces, quadratic surfaces or free-form surfaces, and the embodiments of the present invention do not make specific limitations thereto.

[0120] Optionally, the effective focal length of the left path optical module 11 / right path optical module 12 is f, where 1 mm < f < 5 mm, so that it is easy to achieve that the field of view angles FOV of the left path optical module 11 and the right path optical module 12 satisfy FOV ≥ 75°, which helps to provide a sufficient field of view range. At the same time, the sizes of the lenses used in the left path optical lens group 111 and the right path optical lens group 121 can also be reduced.

[0121] Optionally, the aperture number (F-number) of the left path optical module 11 / right path optical module 12 is F#, where F# > 5. By reasonably controlling the F-number range of the optical system, the depth of field range of the optical system can be increased (for example, the depth of field range of the left path optical module 11 / right path optical module 12 is between 30 mm and 150 mm) on the premise of ensuring a certain resolution ability to meet the requirement that the endoscope can clearly image within a certain range.

[0122] Optionally, the designed object distance of the left path optical module 11 / right path optical module 12 is 50 mm, which is equivalent to the human eye observing an object at 750 mm, more in line with the eye-using habits of the human eye, and can make the 3D effect of the endoscope optical module more real without a sense of dizziness.

[0123] Fig.12 This is a chromatic aberration curve diagram of an endoscope optical module provided by an embodiment of the present invention. As Fig.12 shown, the vertical direction represents the normalization of the field of view angle, 0 represents on the optical axis, and the vertical direction vertex represents the maximum field of view radius; the horizontal direction is the offset amount in the meridional range with 0.5876 μm as the reference, in micrometers (μm). The numbers on the curve in the figure represent the wavelengths represented by the curve, in micrometers (μm), and the maximum field of view is 44.9525 Deg. From Fig.12It can be seen that the vertical axis chromatic aberration can be controlled within the range of (-1μm, 6μm), indicating that the chromatic aberration of the endoscope optical module is well controlled and can meet the application requirements of endoscopic imaging.

[0124] Fig.13 A field curvature and distortion curve diagram of an endoscope optical module provided by an embodiment of the present invention, such as Fig.13 As shown in the figure, in the left coordinate system, the horizontal coordinate represents the magnitude of the zoom lens field curvature, the unit is mm; the vertical coordinate represents the normalized image height, no unit; in the right coordinate system, the horizontal coordinate represents the magnitude of the distortion, the unit is %; the vertical coordinate represents the normalized image height, no unit; Fig.13 It can be seen that the field curvature of the endoscope optical module provided in this embodiment is effectively controlled, and the distortion is also well corrected.

[0125] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An endoscope optical module, characterized in that: It comprises a mirror tube, and a left optical module, a right optical module, a reflection module, a first image sensor and a second image sensor which are arranged in the mirror tube; The left optical module and the right optical module are respectively located on opposite sides of the central axis of the mirror tube; The left optical module comprises a left optical lens group and a left reflective unit arranged along the propagation direction of the incident light, and the left incident light received by the left optical lens group is reflected to the reflective module by the left reflective unit; The right optical module comprises a right optical lens group and a right reflection unit arranged along the propagation direction of the incident light, and the right incident light received by the right optical lens group is reflected to the reflection module by the right reflection unit; The first image sensor and the second image sensor are respectively located on opposite sides of the central axis of the mirror tube; the left-path incident light is reflected by the reflection module to the first image sensor, and the right-path incident light is reflected by the reflection module to the second image sensor; The arrangement direction of the left optical module and the right optical module is a first direction, and the arrangement direction of the first image sensor and the second image sensor is a second direction, wherein the first direction and the second direction intersect.

2. The endoscope optical module according to claim 1, characterized in that: An extension direction of a short side of the first image sensor intersects with an extension direction of a central axis of the mirror tube; An extension direction of a short side of the second image sensor intersects with an extension direction of a central axis of the mirror tube.

3. The endoscope optical module according to claim 1, characterized in that: The angle between the optical axis direction of the left optical lens group and the reflective surface of the left reflective unit is θ1, wherein 40°≤θ1≤50°; The angle between the optical axis direction of the right optical lens group and the reflecting surface of the right reflecting unit is θ2, wherein 40°≤θ2≤50°.

4. The endoscope optical module according to claim 1, characterized in that: The angle between the first direction and the second direction is θ, where 80°≤θ≤100°.

5. The endoscope optical module according to claim 1, characterized in that: The shortest distance between the optical axis of the left optical lens group and the optical axis of the right optical lens group is d1, where d1≥4mm.

6. The endoscope optical module according to claim 1, characterized in that: The left optical lens group includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens and a seventh lens arranged in sequence along the propagation direction of the incident light; The first lens has negative optical power, and the second lens has positive optical power; The third lens has positive optical power, and the fourth lens has negative optical power; or, the third lens has negative optical power, and the fourth lens has positive optical power; The sixth lens has positive optical power, and the seventh lens has negative optical power; or, the sixth lens has negative optical power, and the seventh lens has positive optical power; The right optical lens group and the left optical lens group have the same structure.

7. The endoscope optical module according to claim 6, characterized in that: The refractive index of the third lens is Nd3, and the Abbe number of the third lens is Vd3; the refractive index of the fourth lens is Nd4, and the Abbe number of the fourth lens is Vd4; the refractive index of the sixth lens is Nd6, and the Abbe number of the sixth lens is Vd6; the refractive index of the seventh lens is Nd7, and the Abbe number of the seventh lens is Vd7; wherein, 1.5 <Nd3<1.7,45<Vd3<66;1.7<Nd4<1.8,35<Vd4<50; 1.5 <Nd6<1.7,45<Vd6<65;1.8<Nd7<1.9,25<Vd7<40。 8. The endoscope optical module according to claim 6, characterized in that: The third lens and the fourth lens form a cemented lens group; and / or, The sixth lens and the seventh lens form a cemented lens group.

9. The endoscope optical module according to claim 6, characterized in that: The second lens is a turning prism.

10. The endoscope optical module according to claim 6, characterized in that: The left optical module further includes an eighth lens, and the eighth lens is located in the optical path between the seventh lens and the left reflective unit, or the eighth lens is located in the optical path between the reflective module and the first image sensor; The right optical module and the left optical module have the same structure, and the right optical module and the left optical module are symmetrically arranged relative to the central axis of the mirror tube.

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