Endoscope focusing adjusting mechanism, lens assembly, endoscope and adjusting method

Abstract

The invention discloses an endoscope focusing adjusting mechanism, a lens assembly, an endoscope and an adjusting method, and belongs to the technical field of endoscopes, the adjusting mechanism comprises a movable lens cone and further comprises a driver, the driver comprises a piezoelectric unit, and the piezoelectric unit comprises a first unit and a second unit; in the first unit and the second unit, one of two ends in the polarization direction is used to be fixed relative to the axis position of the movable lens cone, the other end is provided with a flexible cushion layer, and the two ends are located at different axis positions of the movable lens cone; the inclination directions of the first unit and the second unit are opposite. The lens assembly comprises the adjusting mechanism, the endoscope comprises the lens assembly, and the adjusting method is an adjusting method based on the adjusting mechanism. According to the scheme, the limitation of the piezoelectric material stacking thickness on the adjustment stroke size during endoscope zooming is broken through, and a longer-distance zooming movement stroke can be obtained under the condition that the size of the lens assembly is controlled.

Description

Technical Field

[0001] This invention relates to the field of endoscopy technology, and in particular to an endoscopy focusing adjustment mechanism, lens assembly, endoscope, and adjustment method. Background Technology

[0002] An endoscope typically includes a tubular body with a lens assembly at the head end. Existing lens assemblies include the following structural forms: the lens assembly includes a fixed lens group and a movable lens group. During the use of the endoscope, in order to meet the required observation purpose, the position of the movable lens group on the optical axis of the lens assembly is changed to achieve the purpose of zooming / focusing adjustment of the lens assembly.

[0003] Regarding the focus adjustment of the lens assembly, the existing main implementation methods include: 1. the method of pulling with a steel wire rope and a reset spring; 2. the electromagnetic force driving method; 3. the hydraulic / pneumatic driving method; 4. the push-pull method based on the deformation generated by the inverse piezoelectric effect.

[0004] In an endoscopic optical system that achieves focusing adjustment based on the inverse piezoelectric effect, the endoscopic optical system includes a focusing drive mechanism. The focusing drive mechanism uses a piezoelectric material (ceramic) to provide driving force. Specifically, it utilizes the inverse piezoelectric effect of the piezoelectric material, controlling its contraction or expansion by controlling the input of an electrical signal. A connecting mechanism connects the piezoelectric material to the moving frame / tube of the focusing lens, ultimately converting the deformation of the piezoelectric material into the axial displacement of the focusing lens, causing the focusing lens to move forward or backward to achieve the focusing operation of the optical system. Relevant prior art includes the solutions provided in patent application US005490015A (Actuatorapparatus; Olympus Optical); the solutions provided in Chinese patent application CN200580030208.7; and the solutions provided in Chinese patent application CN201310566907.X. In practical applications, the displacement and direction of the movable mirror frame / tube are constrained by the deformation of the piezoelectric material. Therefore, the displacement of the movable mirror assembly along the optical axis installed in the movable mirror frame / tube is limited by the stacking thickness (length or stroke) of the piezoelectric unit.

[0005] To further advance endoscopic technology, it is necessary to optimize the endoscopic optical system. Summary of the Invention

[0006] To address the aforementioned issue of further optimizing the endoscopic optical system, this invention provides an endoscopic focusing adjustment mechanism, a lens assembly, an endoscope, and an adjustment method. This solution overcomes the limitation imposed by the stacking thickness of piezoelectric materials on the adjustment stroke during endoscope zooming, achieving a longer zooming stroke while controlling the size of the lens assembly.

[0007] To address the above problems, the present invention provides an endoscope focusing adjustment mechanism, lens assembly, endoscope, and adjustment method that solve the problems through the following technical points: An endoscope focusing adjustment mechanism includes a movable endoscope barrel and a driver for driving the movable endoscope barrel to move along the optical axis of the endoscope. The driver includes a piezoelectric unit, and the piezoelectric unit includes a first unit and a second unit disposed on the side of the movable endoscope barrel. Both the first unit and the second unit can contract and elongate based on the inverse piezoelectric effect.

[0008] Both Unit 1 and Unit 2 are:

[0009] At both ends of the polarization direction, one end is used to fix the position relative to the axis of the moving lens barrel, and the other end is provided with a flexible pad. The two ends are located at different axial positions of the moving lens barrel. When the contraction occurs, the flexible pad separates from the outer wall of the moving lens barrel. When the elongation occurs, the flexible pad is pressed against the outer wall of the moving lens barrel and undergoes elastic compression.

[0010] The first unit and the second unit are tilted in opposite directions.

[0011] As described above, existing technologies employ piezoelectric materials to achieve endoscope focusing adjustment. However, in practical applications, the deformation of piezoelectric materials is relatively small compared to their original size. Existing technologies often use axial stacking to stack piezoelectric materials into piezoelectric units. Compared to a single piezoelectric material, a piezoelectric unit, as a group of piezoelectric materials, increases the deformation to improve the displacement of the moving lens barrel. The maximum displacement is the maximum deformation of the piezoelectric unit. When the optical system requires a larger focusing stroke, the piezoelectric units need to be stacked to a greater length, which is detrimental to the volume control of the lens assembly.

[0012] In this scheme, both the first and second units, which can contract and elongate based on the inverse piezoelectric effect, can be made of piezoelectric ceramics. Both units are components of a piezoelectric unit, but the difference lies in how they elongate. During elongation, the flexible pads on each unit exert friction on the moving mirror barrel, causing it to move in different directions. The first and second units deform under the influence of electrical signals that excite their respective deformations. During elongation, the flexible pads provide axial force in the corresponding direction to the moving mirror barrel, causing it to move in that direction. After contraction, this prepares the moving mirror barrel for the next elongation push. Relatively speaking, this scheme is limited by current... Due to the deformation of the piezoelectric material and the control of the lens assembly dimensions, the first and second units in this solution do not need to have a large volume or a large stacking thickness. In this context, although the displacement of the moving lens barrel caused by a single extension of the first and second units is small, the high-frequency motion can enable the moving lens barrel to move linearly at high frequency. By controlling the relevant electrical signals, the motion of the first and second units can be converted into the required displacement of the moving lens barrel. At the same time, the displacement is formed by the pushing motion of the piezoelectric units multiple times. Therefore, by controlling the relevant electrical signals to control the number of pushing motions of the moving lens barrel, the motion accuracy of the moving lens barrel can be effectively guaranteed.

[0013] The polarization direction described in the above technical solution is the deformation direction in which the first unit and the second unit deform under the inverse piezoelectric effect. The two ends of the polarization direction are the two ends of the deformation direction. Since the two ends are located at different axial positions of the moving lens barrel, the force exerted on the moving lens barrel when the moving lens barrel deforms has a component force along the axial direction of the moving lens barrel, and under this component force, a driving force is obtained that forces the moving lens barrel to move axially.

[0014] In specific implementation, both the first unit and the second unit are piezoelectric actuators. When the first unit extends to push the moving lens barrel to generate movement along the axis of the moving lens barrel in the first direction, and the second unit extends to push the moving lens barrel to generate movement along the axis of the moving lens barrel in the second direction, and the first and second directions are opposite, if the direction of movement of the moving lens barrel required to achieve focus adjustment is the first direction, then the driving force is generated by the first unit, and the shape of the second unit at this time does not affect the displacement of the moving lens barrel in the required direction generated by the driving force. Conversely, if the direction of movement of the moving lens barrel required to achieve focus adjustment is the second direction, then the driving force is generated by the second unit, and the shape of the first unit at this time does not affect the displacement of the moving lens barrel in the required direction generated by the driving force.

[0015] Unlike existing technologies, this solution utilizes the micro-motion generated by the inverse piezoelectric effect of the piezoelectric unit and leverages frictional coupling to act on the moving endoscope multiple times, causing the moving endoscope to displace in a specific direction. By controlling the number of actions, not only can the final displacement of the moving endoscope be controlled, but the limitation of the existing piezoelectric material stack thickness on the adjustment stroke during endoscope zooming can be overcome. This allows for a longer zooming stroke while controlling the size of the lens assembly. Furthermore, because the displacement of the moving endoscope produced by a single action is small, this solution also features high focusing accuracy.

[0016] Unlike existing technologies, a first unit and a second unit are respectively set for different movement directions of the moving lens barrel. By controlling the actual extension of the first unit and the second unit, for example, when the moving lens barrel is driven to move in the first direction by the first unit, the extension of the first unit and / or the extension of the second unit can be controlled to control the position of the movement stop point when the first unit pushes the moving lens barrel and to control the magnitude of the resistance constraint provided by the second unit for the displacement of the moving lens barrel, thereby further improving the focusing adjustment accuracy.

[0017] In this design, the ends of the first and second units furthest from the axis of the moving lens barrel serve as fixed ends. Therefore, during contraction and elongation, the ends of the first and second units furthest from the axis of the moving lens barrel serve as moving ends, and a flexible pad is provided on the moving ends. This aims to solve the following problems: In existing applications, the most widely used and mature piezoelectric unit material is piezoelectric ceramic. The flexible pad not only provides force protection for the first and second units during elongation, preventing them from being subjected to excessive impact loads, but also provides a greater frictional coupling force to the moving lens barrel compared to the material properties of the piezoelectric unit itself. By preventing the first and second units from slipping relative to the moving lens barrel, the driving capability of the actuator on the moving lens barrel is improved, and the displacement control accuracy of the moving lens barrel is ensured.

[0018] For ease of understanding, the working process of the second unit is explained as follows: Of the two ends of the polarization direction of the second unit, one end is fixed relative to the axis of the moving lens barrel, while the other end has a flexible pad. The two ends of the second unit are located at different axial positions of the moving lens barrel. When the second unit contracts, its flexible pad separates from the outer wall of the moving lens barrel. When it elongates, its flexible pad presses against the outer wall of the moving lens barrel, resulting in elastic compression and pushing the moving lens barrel to move. The first unit is used in the same way as the second unit during operation.

[0019] As a further technical solution for the endoscope focusing adjustment mechanism:

[0020] In practical use, to fix the position of one end relative to the axis of the moving lens tube, when the moving lens tube is placed inside the objective lens tube, the outer end of the first unit and the second unit can be directly or indirectly fixed to the objective lens tube. For example, the end can be directly fixed to the objective lens tube to fix its position relative to the axis of the moving lens tube. Preferably, in order to enable the driver to be assembled as a whole, so that it can be nested on the outside of the moving lens tube in a whole manner to complete the assembly with the moving lens tube in practical use, the driver is configured as follows: the driver also includes a fixed ring and a flexible ring, both of which are sleeved on the outside of the moving lens tube. The outer ends of the first unit and the second unit are fixed to the fixed ring, and the inner ends of the first unit and the second unit are fixedly connected to the flexible ring. In this solution, the outer end of the polarization direction relative to the moving lens barrel is fixed to a fixed ring, and the inner end is fixed to a flexible ring. Specifically, in the adjustment mechanism during use, the fixed ring is used to fix the position of the moving lens barrel. The flexible ring provides a corresponding flexible pad. When the elongation occurs, the flexible ring pushes the moving lens barrel to move. When the contraction occurs, it drives the flexible ring to move locally away from the moving lens barrel, thereby reducing the resistance in the direction of adjusting the position of the moving lens barrel. This solution is a technical solution that uses the objective lens barrel as an indirect fixing base. More specifically, when the first unit pushes the movable lens barrel in the first direction, the length of the second unit can be controlled to create a certain amount of compression or no compression between the flexible ring area where the second unit acts and the movable lens barrel. When compression is present, this compression can be used to control the displacement of the movable lens barrel when acted upon by the first unit in a single instance, thus maintaining the position of the movable lens barrel during the time period when the first unit is not acting on it. When displacement control is not required, or when the position of the movable lens barrel does not change or a change is acceptable during the non-acting time period, the second unit is configured to not compress the movable lens barrel, thereby achieving higher position adjustment efficiency. Conversely, when the second unit acts on the movable lens barrel to achieve position adjustment in the second direction, the method of action of the first unit on the movable lens barrel can also be adjusted as needed.

[0021] In existing technology, endoscope lens assemblies also include a fixed lens group and a movable lens group mounted on the same optical axis as the fixed lens group in a movable endoscope tube. During the movement of the movable endoscope tube, the movable lens group moves synchronously with the movable endoscope tube. Based on this, a further solution is as follows: there are multiple first units and multiple second units. The first units are evenly distributed in a ring relative to the axis of the movable endoscope tube, and the second units are also evenly distributed in a ring relative to the axis of the movable endoscope tube. In practical use, depending on the required direction of movement of the movable endoscope tube, all first units or all second units can move synchronously. This can be used to achieve the following: by evenly distributing the first and second units in the circumferential direction of the movable endoscope tube, and through the synchronous movement, the lateral forces experienced by the movable endoscope tube and other components in the lens assembly during the movement of the movable endoscope tube by the driver can be avoided or reduced. By avoiding or reducing wear caused by the lateral forces, the optical axis maintenance accuracy of the lens assembly can be improved.

[0022] Based on the volume of existing conventional piezoelectric materials and the size requirements of the piezoelectric unit in this solution, a preferred application is to set the assembly formed by the fixed ring, the first unit, the second unit, and the flexible ring to have a smaller size. To facilitate the installation of this assembly on the lens assembly, as a specific solution for fixing the position of the driver relative to the objective lens barrel, it is set as follows: it also includes a base and a connecting ring, both of which are cylindrical.

[0023] The inner wall of the base is provided with a positioning shoulder, the fixing ring is embedded in the base and coaxial with the base, one end of the fixing ring is engaged with the positioning shoulder, and the connecting ring is embedded in the base and its end is connected to the other end of the fixing ring.

[0024] The movable lens barrel is constrained to be coaxial with the base by contact between its outer wall and the inner wall of the base and / or the connecting ring. In this design, one end of the connecting ring is embedded in the base, and the fixing ring is clamped between the positioning shoulder and the end face of the connecting ring. The coaxiality of the fixing ring and the base can be achieved based on the mating pair formed by the outer wall of the fixing ring and the inner wall of the base. The contact between the outer wall of the movable lens barrel and the inner wall of the base and / or the connecting ring constrains the axial position of the movable lens barrel on this adjustment mechanism, thereby ensuring the optical axis accuracy of the lens assembly. When specifically applied to a lens assembly, the base and / or the connecting ring are assembled at a specific axial position of the objective lens barrel, and the optical axis of the movable lens barrel is kept coaxial with the optical axis of the fixed lens group on the objective lens barrel. In this way, the position of the driver relative to the objective lens barrel can be fixed relatively well.

[0025] To prevent the moving lens barrel from deflecting relative to the objective lens barrel during operation, the following design is employed: one of the base and the moving lens barrel has a guide groove parallel to the optical axis of the moving lens barrel, and the other has a boss embedded in the guide groove. The boss and the guide groove form a guiding structure for the moving lens barrel's movement relative to the base. In practical application, after the base is fixed to the objective lens barrel, the interaction between the side of the boss and the side of the guide groove prevents the moving lens barrel from rotating relative to the objective lens barrel during movement.

[0026] As a technical solution that easily achieves synchronous operation of all first units and all second units, it is configured such that: the first units have a common first power supply unit, which is used to synchronously supply power to each first unit;

[0027] The second unit has a common second power supply unit, which is used to synchronously supply power to each second unit. In practical use, the fixed ring can be set as a ring structure that is itself conductive. The preferred option is to use a copper ring with good conductivity that is not prone to generating abrasive particles during high-frequency operation. The flexible ring is made of insulating material, and a first conductive ring that contacts all the first units is set on the inner surface of the flexible ring. A second conductive ring that contacts all the second units is set on the inner surface of the flexible ring. The first and second conductive rings are fixedly connected to the flexible ring by means of bonding, pressing, or partial potting. The fixed ring and the first conductive ring are components of the first power supply unit, and the fixed ring and the second conductive ring are components of the second power supply unit. In this way, all the first units exist in parallel between the fixed ring and the first conductive ring, and all the second units exist in parallel between the fixed ring and the second conductive ring.

[0028] To ensure reliable fixation of the first and second units on the fixing ring and maintain stable positional accuracy, the following configuration is adopted: each of the first and second units is equipped with a slot on the inner wall of the fixing ring, and the outer ends of each of the first and second units are embedded in the corresponding slot. In this scheme, the high precision of the slot machining can be used to maintain the positional accuracy of the first and second units on the fixing ring. A preferred approach is to control the relevant dimensions so that the first and second units are constrained to specific positions in the slot by the sidewalls of the corresponding slots and obtain specific polarization directions.

[0029] To ensure that the flexible ring can be reliably constrained between the first unit and the second unit, and to ensure that the flexible ring has a stable working surface for the driver to push the moving mirror barrel, the following configuration is provided: both the inner and outer sides of the flexible ring are provided with flanges coaxial with the flexible ring.

[0030] The first unit is distributed on one side of the outer flange of the flexible ring, and the second unit is distributed on the other side of the outer flange of the flexible ring; the first unit and the second unit are both located on the side of the outer flange of the flexible ring.

[0031] Along the axial direction of the flexible ring, the inner flange of the flexible ring is an arc-shaped surface that protrudes from the center toward the side where the axis of the flexible ring is located;

[0032] The inner flange of the flexible ring is located on the extension line of the polarization direction of the first unit and the second unit. In this scheme, the outer flange of the flexible ring forms an inclined surface on the outer side of the flexible ring. One inclined surface serves as the connection surface connecting the flexible ring to the first unit, and the other inclined surface serves as the connection surface connecting the flexible ring to the second unit. In this way, the flexible ring can be well constrained between the first unit and the second unit while maintaining a simple flexible ring configuration. A preferred application is that the inner end face of the first unit is in contact with the corresponding inclined surface, and the inner end face of the second unit is in contact with the corresponding inclined surface. For example, when the flexible ring is in a free state and both the fixed ring and the flexible ring are coaxial with the moving lens barrel, the end faces of the first unit and the second unit and their respective corresponding inclined surfaces are located on the same plane, and the angle between this plane and the moving lens barrel is an acute angle. Because the flange on the inner side of the flexible ring is located on the extension line of the polarization direction of the first and second units, and the flange protrudes relative to the inner side of the flexible ring, when the first and second units move, the inner wall surface of the flange serves as the contact surface between the flexible ring and the moving lens barrel, so that the flexible ring has a relatively stable working surface that interacts with the moving lens barrel. Due to the flange located on the inner side of the flexible ring, it can be used to form a flexible ring that can be folded inward and outward relatively easily when one of the first and second units extends and the other contracts. One side narrows and the other side expands. The side with narrowed diameter is used to generate the thrust for the movement of the moving lens barrel, and the side with expanded diameter releases the moving lens barrel so that the moving lens barrel has less movement resistance. When the inner wall surface of the inner flange serves as the contact surface, the increase in movement resistance of the moving lens barrel caused by contact with the moving lens barrel at other positions on the inner wall of the flexible ring can be reduced. A preferred application is that both the inner and outer flanges of the flexible ring are located at the middle of the flexible ring's length direction. The first and second units are symmetrical with respect to the middle, so that the moving lens barrel has similar motion performance when moving in two directions. This ensures that the adjustment mechanism has good consistency when driving the moving lens barrel, facilitating motion control. In its free state, the inner flange has a smooth cylindrical inner wall. From one end of the flexible ring to the other, the diameter of the cylindrical inner wall first decreases continuously and then increases continuously. The minimum diameter is located at the middle of the flange axis direction. This ensures that when the folding occurs, the inner flange and the moving lens barrel have sufficient contact area to effectively drive the moving lens barrel.

[0033] This solution provides a lens assembly that includes any of the endoscope focusing adjustment mechanisms described above. It is easy to understand that this solution is a specific application of the endoscope focusing adjustment mechanism on a lens assembly, and the lens assembly includes the lens assembly of the endoscope focusing adjustment mechanism.

[0034] This solution provides an endoscope including the lens assembly described above. It is easy to understand that this solution is a specific application of the lens assembly in an endoscope, and the endoscope includes the lens assembly.

[0035] This solution provides an endoscope focusing adjustment method, which is based on the endoscope focusing adjustment mechanism described in any of the above methods. The method is as follows: providing an electrical signal with a voltage that changes in a wave shape to the first unit and the second unit, so that the first unit and the second unit contract and elongate based on the inverse piezoelectric effect.

[0036] When the first unit elongates, the flexible padding layer compresses the moving lens barrel, providing thrust to the moving lens barrel and causing it to move in the first direction.

[0037] When the second unit elongates, the flexible padding layer compresses the moving lens barrel, providing thrust to the moving lens barrel and causing it to move in the second direction.

[0038] The first direction and the second direction are both along the optical axis and are opposite in direction;

[0039] The displacement of the moving lens barrel is adjusted according to the number of times the first unit and / or the second unit provides thrust to the moving lens barrel.

[0040] The present invention has the following beneficial effects:

[0041] This solution breaks through the limitations of existing methods that use the stacking thickness of piezoelectric materials to adjust the zoom stroke of endoscopes. It can achieve a longer zoom stroke while controlling the size of the lens assembly, meeting the requirements of large stroke drive. At the same time, since the displacement generated by moving the lens barrel in a single action is small, this solution also has the characteristics of high focusing adjustment accuracy, which can ensure accurate focusing of optical devices, precise magnification control, and high resolution.

[0042] By controlling the actual elongation of the first and second units, the force of the actuator on the moving lens barrel can be mutually constrained. When mechanical limiting is used, the adjustment of any moving distance within the mechanical limiting can be realized, thereby further improving the focusing adjustment accuracy.

[0043] The above-mentioned flexible pad not only provides stress protection for the first and second units when they are extended, preventing them from being subjected to excessive impact loads, but also provides a greater frictional coupling force for the moving lens barrel compared to the material properties of the piezoelectric unit itself. By preventing the first and second units from slipping relative to the moving lens barrel, the driving capability of the actuator on the moving lens barrel is improved and the displacement control accuracy of the moving lens barrel is guaranteed.

[0044] In this solution, the driver is a structure that moves the outside of the lens barrel and does not affect the propagation of light waves in the optical path of the lens assembly.

[0045] This solution achieves the adjustment of the moving lens barrel position without requiring other linkage or motion conversion mechanisms, which is beneficial for simplifying the structural design of the lens assembly. At the same time, it can drive the moving lens barrel to move smoothly with high power while keeping the driver size small. Attached Figure Description

[0046] Figure 1 This is an exploded structural diagram of a partial structure of a specific embodiment of an endoscope lens assembly described in this solution;

[0047] Figure 2 This is a two-dimensional cross-sectional view of a specific embodiment of the driver described in this solution;

[0048] Figure 3 This is a three-dimensional cross-sectional view of a specific embodiment of the driver described in this solution;

[0049] Figure 4 This is a two-dimensional cross-sectional view of a specific embodiment of the assembly structure formed by the fixing ring and the piezoelectric unit described in this solution;

[0050] Figure 5 A three-dimensional sectional view of a specific embodiment of the assembly structure formed by the fixing ring and the piezoelectric unit described in this solution;

[0051] Figure 6 This is a three-dimensional cross-sectional view of a partial structure of a specific embodiment of an endoscope lens assembly described in this solution;

[0052] Figure 7 This is a cross-sectional view of a specific embodiment of an endoscope lens assembly described in this solution;

[0053] Figure 8 This is a cross-sectional view of a specific embodiment of an endoscope lens assembly described in this solution, and... Figure 7 The structures provided in this embodiment are different, as they have different lens forms;

[0054] Figure 9This is a three-dimensional structural diagram of a specific embodiment of an endoscope lens assembly described in this solution, and... Figure 1 The structures provided in this embodiment are different, as they have different lens forms;

[0055] Figure 10 for Figure 9 A three-dimensional cross-sectional view of the driver used in the process;

[0056] Figure 11 for Figure 9 A three-dimensional sectional view of the structure shown;

[0057] Figure 12 for Figure 9 A cross-sectional view of the adjusting mechanism in the structure shown;

[0058] Figure 13 for Figure 9 The cross-sectional view of the adjusting mechanism in the structure shown is... Figure 12 There is a difference; the diagram shows different driver states.

[0059] Figure 14 for Figure 9 The cross-sectional view of the adjusting mechanism in the structure shown is... Figure 12 and Figure 13 There is a difference; the diagram shows different driver states.

[0060] The reference numerals in the attached figures are as follows: 1. Fixed lens group; 2. Moving lens group; 3. Objective lens barrel; 31. First lens barrel; 32. Second lens barrel; 4. Driver; 41. Piezoelectric unit; 411. First unit; 412. Second unit; 42. Fixed ring; 421. Slot; 43. Flexible ring; 431. Flange; 5. Base; 51. Guide groove; 6. Moving lens barrel; 61. Boss; 7. Connecting ring. Detailed Implementation

[0061] The present invention will be further described in detail below with reference to the embodiments, but the present invention is not limited to the following embodiments:

[0062] Example 1:

[0063] like Figures 1 to 14 As shown, an endoscope focusing adjustment mechanism includes a movable endoscope tube 6 and a driver 4 for driving the movable endoscope tube 6 to move along the optical axis of the endoscope. The driver 4 includes a piezoelectric unit 41, which includes a first unit 411 and a second unit 412 disposed on the side of the movable endoscope tube 6. Both the first unit 411 and the second unit 412 can contract and elongate based on the inverse piezoelectric effect.

[0064] Both Unit 1 411 and Unit 2 412 are:

[0065] Of the two ends of the polarization direction, one end is used to fix the position relative to the axis of the movable lens barrel 6, and the other end is provided with a flexible pad. The two ends are located at different axial positions of the movable lens barrel 6. When the contraction occurs, the flexible pad separates from the outer wall of the movable lens barrel 6. When the elongation occurs, the flexible pad is pressed against the outer wall of the movable lens barrel 6 and undergoes elastic compression.

[0066] The tilting directions of the first unit 411 and the second unit 412 are opposite.

[0067] As described above, existing technologies employ piezoelectric materials to achieve endoscope focusing adjustment. However, in practical applications, the deformation of piezoelectric materials is relatively small compared to their original size. Existing technologies often use axial stacking to stack piezoelectric materials into piezoelectric units 41. Compared to a single piezoelectric material, piezoelectric units 41, as a group of piezoelectric materials, increase the deformation to improve the displacement of the moving lens barrel 6. The maximum displacement is the maximum deformation of the piezoelectric unit 41. When the optical system requires a larger focusing stroke, the piezoelectric units 41 need to be stacked to a greater length, which is detrimental to the volume control of the lens assembly.

[0068] In this scheme, both the first unit 411 and the second unit 412, which can contract and elongate based on the inverse piezoelectric effect, can be made of piezoelectric ceramic (PZT-5H). Both the first unit 411 and the second unit 412 are components of the piezoelectric unit 41. The difference lies in that, during elongation, the first unit 411 and the second unit 412 utilize the frictional force of their respective flexible pads on the moving mirror barrel 6 to cause the moving mirror barrel 6 to have different displacement directions. The first unit 411 and the second unit 412 deform under the electrical signal that excites their respective deformation. During elongation, the flexible pads provide axial force to the moving mirror barrel 6 in the corresponding direction, causing the moving mirror barrel 6 to move in that axis direction. After contraction, this prepares for the next elongation and pushing of the moving mirror barrel 6. In this case, due to the limitations of the deformation of existing piezoelectric materials and the size control of lens components, the first unit 411 and the second unit 412 do not need to adopt a large volume or a large stacking thickness. In this context, although the displacement of the moving lens barrel 6 caused by the single extension of the first unit 411 and the second unit 412 is small, the high-frequency motion can make the moving lens barrel 6 move linearly at high frequency. By controlling the relevant electrical signals, the motion of the first unit 411 and the second unit 412 can be converted into the required displacement of the moving lens barrel 6. At the same time, the displacement is formed by the pushing motion of the piezoelectric unit 41 multiple times. Therefore, by controlling the relevant electrical signals to control the number of times the moving lens barrel 6 is pushed, the motion accuracy of the moving lens barrel 6 can be effectively guaranteed.

[0069] The polarization direction described in the above technical solution is the deformation direction in which the first unit 411 and the second unit 412 deform under the inverse piezoelectric effect. The two ends of the polarization direction are the two ends of the deformation direction. Since the two ends are located at different axial positions of the moving lens barrel 6, the force exerted on the moving lens barrel 6 when it deforms has a component force along the axial direction of the moving lens barrel 6, and under this component force, a driving force is obtained that forces the moving lens barrel 6 to move axially.

[0070] In specific implementation, when the first unit 411 extends to push the movable lens barrel 6 to generate movement along the axis of the movable lens barrel 6 in the first direction, and the second unit 412 extends to push the movable lens barrel 6 to generate movement along the axis of the movable lens barrel 6 in the second direction, and the first direction and the second direction are opposite, if the direction of movement of the movable lens barrel 6 required to achieve focus adjustment is the first direction, then the driving force is generated by the first unit 411, and the shape of the second unit 412 at this time does not affect the displacement of the movable lens barrel 6 in the required direction generated by the driving force. Conversely, if the direction of movement of the movable lens barrel 6 required to achieve focus adjustment is the second direction, then the driving force is generated by the second unit 412, and the shape of the first unit 411 at this time does not affect the displacement of the movable lens barrel 6 in the required direction generated by the driving force.

[0071] Unlike existing technologies, this solution utilizes the micro-motion generated by the piezoelectric unit 41 based on the inverse piezoelectric effect and employs frictional coupling to act on the movable endoscope tube 6 multiple times, causing the movable endoscope tube 6 to produce displacement in a specific direction. By controlling the number of actions, not only can the final displacement of the movable endoscope tube 6 be controlled, but the limitation of the adjustment stroke during endoscope zooming by the existing piezoelectric material stacking thickness can be overcome. A longer zooming stroke can be obtained while controlling the size of the lens assembly. At the same time, since the displacement generated by the movable endoscope tube 6 in a single action is small, this solution also has the characteristic of high focusing adjustment accuracy.

[0072] Unlike existing technologies, a first unit 411 and a second unit 412 are respectively provided for different movement directions of the movable lens barrel 6. By controlling the actual extension of the first unit 411 and the second unit 412, for example, when the movable lens barrel 6 is driven to move in the first direction by the first unit 411, the extension of the first unit 411 and / or the extension of the second unit 412 can be controlled to control the position of the movement stop point when the first unit 411 pushes the movable lens barrel 6 and to control the magnitude of the resistance constraint provided by the second unit 412 for the displacement of the movable lens barrel 6, thereby further improving the focusing adjustment accuracy.

[0073] In this scheme, the ends of the first unit 411 and the second unit 412 that are away from the axis of the moving lens barrel 6 are fixed ends. Therefore, when the contraction and elongation occur, the ends of the first unit 411 and the second unit 412 that are away from the axis of the moving lens barrel 6 are the moving ends, and a flexible pad is provided on the moving ends. This is intended to solve the following problems: In existing applications, the piezoelectric unit 41 material is piezoelectric ceramic, which is widely used and mature. The above flexible pad can not only provide force protection for the first unit 411 and the second unit 412 when they elongate, avoiding excessive impact load on the first unit 411 and the second unit 412, but also provide a greater frictional coupling force for the moving lens barrel 6 compared to the material properties of the piezoelectric unit 41 itself. By preventing the first unit 411 and the second unit 412 from slipping relative to the moving lens barrel 6, the driving capability of the actuator 4 on the moving lens barrel 6 is improved and the displacement control accuracy of the moving lens barrel 6 is guaranteed.

[0074] For ease of understanding, the working process of the second unit 412 is illustrated as follows: One end of the second unit 412 is fixed relative to the axis of the moving lens barrel 6, while the other end has a flexible pad. The two ends of the second unit 412 are located at different axial positions of the moving lens barrel 6. When the second unit 412 contracts, its flexible pad is isolated from the outer wall of the moving lens barrel 6. When it elongates, its flexible pad is pressed against the outer wall of the moving lens barrel 6 and undergoes elastic compression. The first unit 411 is used in the same way as the second unit 412 during operation. When a driving electrical signal is applied to the second unit 412, if the voltage direction is opposite to the polarization direction, the second unit 412 is in a compressed state; if the voltage direction is consistent with the polarization direction, the second unit 412 is in a stretched state. The deformation of the second unit 412 is ΔL = d. 33 FVL / h, the deformation magnitude is determined by the working voltage FV, the length L of the piezoelectric ceramic, the height h of the ceramic layer, and the deformation coefficient d of the piezoelectric material. 33 The decision was made.

[0075] Example 2:

[0076] This embodiment is a further refinement of embodiment 1:

[0077] In practical use, to fix the position of one end relative to the axis of the movable lens tube 6, when the movable lens tube 6 is placed inside the objective lens tube 3, the outer end of the first unit 411 and the second unit 412 can be directly or indirectly fixed to the objective lens tube 3. For example, the end can be directly fixed to the objective lens tube 3 to fix its position relative to the axis of the movable lens tube 6. Preferably, in order to enable the driver 4 to be assembled as a whole, so that it can be nested in the outer side of the movable lens tube 6 in a whole manner to complete the assembly with the movable lens tube 6 in practical use, the driver 4 is configured as follows: the driver 4 also includes a fixing ring 42 and a flexible ring 43. The fixing ring 42 and the flexible ring 43 are both sleeved on the outer side of the movable lens tube 6. The outer ends of the first unit 411 and the second unit 412 are fixed to the fixing ring 42, and the inner ends of the first unit 411 and the second unit 412 are fixedly connected to the flexible ring 43. In this solution, the outer end of the polarization direction relative to the moving lens barrel 6 is fixed to the fixing ring 42, and the inner end is fixed to the flexible ring 43. Specifically, the fixing ring 42 is used to fix the position of the adjusting mechanism relative to the moving lens barrel 6 in the use state. The flexible ring 43 provides a corresponding flexible pad. When the elongation occurs, the flexible ring 43 pushes the moving lens barrel 6 to move. When the contraction occurs, it drives the flexible ring 43 to move locally away from the moving lens barrel 6 to reduce the resistance in the position adjustment direction of the moving lens barrel 6. This solution is a technical solution that uses the objective lens barrel 3 as the indirect fixing base. More specifically, when the first unit 411 pushes the movable lens barrel 6 in the first direction, the length of the second unit 412 can be controlled to create a certain amount of compression or no compression between the flexible ring 43 area acted upon by the second unit 412 and the movable lens barrel 6. When compression is present, this compression can be used to control the displacement of the movable lens barrel 6 when acted upon by the first unit 411 in a single instance, and to maintain the position of the movable lens barrel 6 during the time period when the first unit 411 is not acting upon it. When the displacement control is not required, or when the position of the movable lens barrel 6 does not change or a change is acceptable during the time period when no action is taken, the second unit 412 is in a state of no compression on the movable lens barrel, thereby achieving higher position adjustment efficiency of the movable lens barrel 6. Conversely, when the second unit 412 acts on the movable lens barrel 6 to achieve position adjustment in the second direction, the action mode of the first unit 411 on the movable lens barrel 6 can also be adjusted as needed.

[0078] Example 3:

[0079] This embodiment is a further refinement of embodiment 1:

[0080] In the prior art, the endoscope lens assembly also includes a fixed lens group 1 and a movable lens group 2 mounted on the same optical axis as the fixed lens group 1 in the movable endoscope tube 6. During the movement of the movable endoscope tube 6, the movable lens group 2 moves synchronously with the movable endoscope tube 6. Based on this, a further solution is as follows: there are multiple first units 411 and multiple second units 412. The first units 411 are evenly distributed in a ring relative to the axis of the movable endoscope tube 6, and the second units 412 are also evenly distributed in a ring relative to the axis of the movable endoscope tube 6. In practical use, depending on the required direction of movement of the movable endoscope tube 6, all first units 411 or all second units 412 can move synchronously. This can achieve the following: by evenly distributing the first units 411 and second units 412 in the circumferential direction of the movable endoscope tube 6, and through the synchronous movement, the lateral forces experienced by the movable endoscope tube 6 and other components in the lens assembly during the movement of the movable endoscope tube 6 by the driver 4 can be avoided or reduced. By avoiding or reducing wear caused by the lateral forces, the optical axis maintenance accuracy of the lens assembly can be improved.

[0081] Example 4:

[0082] This embodiment is a further refinement of embodiment 2:

[0083] Based on the volume of existing conventional piezoelectric materials and the size requirements of the piezoelectric unit 41 in this solution, a preferred application is to set the assembly formed by the fixing ring 42, the first unit 411, the second unit 412, and the flexible ring 43 to have a smaller size. To facilitate the installation of this assembly on the lens assembly, as a specific solution for fixing the position of the driver 4 relative to the objective lens barrel 3, it is set as follows: it also includes a base 5 and a connecting ring 7, both of which are cylindrical.

[0084] The inner wall of the base 5 is provided with a positioning shoulder, the fixing ring 42 is embedded in the base 5 and coaxial with the base 5, one end of the fixing ring 42 is engaged with the positioning shoulder, and the connecting ring 7 is embedded in the base 5 and its end is connected to the other end of the fixing ring 42.

[0085] The movable lens barrel 6 is constrained to be coaxial with the base 5 by contacting the inner wall of the base 5 and / or the connecting ring 7 through its outer wall. In this design, one end of the connecting ring 7 is embedded in the base 5, and the fixing ring 42 is clamped between the positioning shoulder and the end face of the connecting ring 7. The coaxiality of the fixing ring 42 and the base 5 can be achieved based on the mating pair formed by the outer wall of the fixing ring 42 and the inner wall of the base 5. The axial position of the movable lens barrel 6 on this adjustment mechanism is constrained by the contact between the outer wall of the movable lens barrel 6 and the inner wall of the base 5 and / or the connecting ring 7 to ensure the optical axis accuracy of the lens assembly. When specifically applied to a lens assembly, the base 5 and / or the connecting ring 7 are assembled at a specific axial position of the objective lens barrel 3 and the optical axis of the movable lens barrel 6 is kept coaxial with the optical axis of the fixed lens group 1 on the objective lens barrel 3. In this way, the position of the driver 4 relative to the objective lens barrel 3 can be fixed relatively well.

[0086] Example 5:

[0087] This embodiment is a further refinement of embodiment 4:

[0088] To prevent the moving lens barrel 6 from deflecting relative to the objective lens barrel 3 during operation of the actuator 4, the following configuration is provided: One of the base 5 and the moving lens barrel 6 has a guide groove 51 parallel to the optical axis of the moving lens barrel 6, and the other has a boss 61 embedded in the guide groove 51. The boss 61 and the guide groove 51 form a guiding structure for the moving lens barrel 6 to move relative to the base 5. In practical application, after the base 5 is fixed to the objective lens barrel 3, the interaction between the side of the boss 61 and the side of the guide groove 51 prevents the moving lens barrel 6 from rotating relative to the objective lens barrel 3 during movement.

[0089] Example 6:

[0090] This embodiment is a further refinement of embodiment 3:

[0091] As a technical solution that easily achieves synchronous operation of all first units 411 and all second units 412, it is configured such that: the first units 411 have a common first power supply unit, which is used to synchronously supply power to each first unit 411;

[0092] The second unit 412 has a common second power supply unit, which is used to synchronously supply power to each second unit 412. In specific use, the fixed ring 42 can be set as a ring structure that is conductive. The preferred option is to use a copper ring with good conductivity that is not prone to generating abrasive particles during high-frequency operation. The flexible ring 43 is made of insulating material, and a first conductive ring that contacts all the first units 411 is set on the inner side of the flexible ring 43. A second conductive ring that contacts all the second units 412 is set on the inner side of the flexible ring 43. The first conductive ring and the second conductive ring are fixedly connected to the flexible ring 43 by means of bonding, pressing, partial potting, etc. The fixed ring 42 and the first conductive ring are components of the first power supply unit, and the fixed ring 42 and the second conductive ring are components of the second power supply unit. In this way, all the first units 411 exist in parallel between the fixed ring 42 and the first conductive ring, and all the second units 412 exist in parallel between the fixed ring 42 and the second conductive ring.

[0093] Example 7:

[0094] This embodiment is a further refinement of embodiment 3:

[0095] To ensure reliable fixation of the first unit 411 and the second unit 412 on the fixing ring 42 and maintain stable positional accuracy of the first unit 411 and the second unit 412 on the fixing ring 42, the following configuration is provided: each of the first unit 411 and the second unit 412 is provided with a slot 421 located on the inner wall of the fixing ring 42, and the outer ends of each of the first unit 411 and the second unit 412 are embedded in the corresponding slot 421. In this scheme, the high precision of the slot 421 machining can be used to maintain the positional accuracy of the first unit 411 and the second unit 412 on the fixing ring 42. A preferred application is to control the relevant dimensions so that the first unit 411 and the second unit 412 are constrained by the sidewall of the corresponding slot 421 to a specific position in the slot 421 and obtain a specific polarization direction.

[0096] Example 8:

[0097] This embodiment is a further refinement of embodiment 7:

[0098] In order to ensure that the flexible ring 43 can be reliably constrained between the first unit 411 and the second unit 412, and to ensure that the flexible ring 43 has a stable working surface for the driver 4 to push the moving mirror tube 6 to move, the following configuration is provided: both the inner and outer sides of the flexible ring 43 are provided with flanges 431 coaxial with the flexible ring 43.

[0099] The first unit 411 is distributed on one side of the flange 431 on the outer side of the flexible ring 43, and the second unit 412 is distributed on the other side of the flange 431 on the outer side of the flexible ring 43; the first unit 411 and the second unit 412 are both located on the side of the flange 431 on the outer side of the flexible ring 43.

[0100] In the axial direction of the flexible ring 43, the flange 431 on the inner side of the flexible ring 43 is an arc-shaped surface that protrudes from the middle towards the side where the axis of the flexible ring 43 is located.

[0101] The inner flange 431 of the flexible ring 43 is located on the extension line of the polarization direction of the first unit 411 and the second unit 412. In this scheme, the outer flange 431 of the flexible ring 43 forms an inclined surface on the outer side of the flexible ring 43. One inclined surface serves as the connection surface connecting the flexible ring 43 and the first unit 411, and the other inclined surface serves as the connection surface connecting the flexible ring 43 and the second unit 412. In this way, with the simple configuration of the flexible ring 43, the flexible ring 43 can be well constrained between the first unit 411 and the second unit 412. A preferred application is that the inner end face of the first unit 411 is in contact with the corresponding inclined surface, and the inner end face of the second unit 412 is in contact with the corresponding inclined surface. Since the flange 431 on the inner side of the flexible ring 43 is located on the extension line of the polarization direction of the first unit 411 and the second unit 412, and the flange 431 protrudes relative to the inner side of the flexible ring 43, when the first unit 411 and the second unit 412 are in operation, the inner wall surface of the flange 431 serves as the contact surface between the flexible ring 43 and the moving lens barrel 6, so that the flexible ring 43 has a relatively stable working surface that interacts with the moving lens barrel 6. Because it has the flange 431 located on the inner side of the flexible ring 43, it can be used as a contact surface when the first unit 411 and the second unit 412 are in operation. 1. In the second unit 412, when one of them extends and the other contracts, the flexible ring 43 can be formed relatively easily by folding inward and outward: one side narrows and the other side expands. The narrowed side is used to generate the thrust for moving the movable lens barrel 6, and the expanded side releases the movable lens barrel 6 so that the movable lens barrel 6 has less moving resistance. When the inner wall surface of the inner flange 431 serves as the contact surface, the increase in moving resistance of the movable lens barrel 6 caused by contact with the movable lens barrel 6 at other positions of the inner wall of the flexible ring 43 can be reduced. A preferred application is that both the inner flange 431 and the outer flange 431 of the flexible ring 43 are located at the middle of the length direction of the flexible ring 43. The first unit 411 and the second unit 412 are symmetrical with respect to the middle, so that the moving lens barrel 6 has similar motion performance when moving in two directions. This makes the adjustment mechanism have better consistency when driving the moving lens barrel 6 to move, so as to facilitate motion control. In the free state, the inner wall surface of the inner flange 431 is cylindrical, and from one end of the flexible ring 43 to the other end, the diameter of the cylindrical inner wall surface first decreases continuously and then increases continuously. The minimum diameter position is located at the middle of the axial direction of the flange 431. This is to ensure that when the folding occurs, the inner flange 431 and the moving lens barrel 6 have sufficient contact area to effectively drive the moving lens barrel 6 to move.

[0102] Example 9:

[0103] Based on Embodiment 1, this embodiment provides a lens assembly including the endoscope focusing adjustment mechanism described in Embodiment 1. It is easy to understand that this solution is a specific application of the endoscope focusing adjustment mechanism on the lens assembly, and the lens assembly includes the lens assembly of the endoscope focusing adjustment mechanism.

[0104] Example 10:

[0105] Based on Embodiment 9, this embodiment provides an endoscope including the lens assembly described in Embodiment 9. It is easy to understand that this solution is a specific application of the lens assembly in an endoscope, and the endoscope includes the lens assembly.

[0106] Example 11:

[0107] Based on Embodiment 1, this embodiment provides an endoscope focusing adjustment method. The method is based on the endoscope focusing adjustment mechanism described in Embodiment 1. The method is as follows: provide an electrical signal with a wave-like voltage to the first unit 411 and the second unit 412, so that the first unit 411 and the second unit 412 contract and elongate based on the inverse piezoelectric effect.

[0108] When the first unit 411 extends, the flexible padding layer compresses the movable lens barrel 6 to provide thrust to the movable lens barrel 6, causing the movable lens barrel 6 to move in the first direction.

[0109] When the second unit 412 extends, the flexible padding layer compresses the movable lens barrel 6 to provide thrust to the movable lens barrel 6, causing the movable lens barrel 6 to move in the second direction.

[0110] The first direction and the second direction are both along the optical axis and are opposite in direction;

[0111] The displacement of the movable lens tube 6 is adjusted according to the number of times the first unit 411 and / or the second unit 412 provides thrust to the movable lens tube 6.

[0112] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific embodiments of the present invention are limited to these descriptions. For those skilled in the art, other embodiments derived without departing from the technical solution of the present invention should be included within the scope of protection of the present invention.

Claims

1. An endoscope focusing adjustment mechanism, comprising a movable endoscope tube (6), and a driver (4) for driving the movable endoscope tube (6) to move along the optical axis of the endoscope, said driver (4) comprising a piezoelectric unit (41), characterized in that, The piezoelectric unit (41) includes a first unit (411) and a second unit (412) disposed on the side of the movable lens barrel (6). Both the first unit (411) and the second unit (412) can shrink and elongate based on the inverse piezoelectric effect. Both Unit 1 (411) and Unit 2 (412) are: At both ends of the polarization direction, one end is used to fix the position relative to the axis of the moving lens barrel (6), and the other end is provided with a flexible pad. The two ends are located at different axial positions of the moving lens barrel (6). When the contraction occurs, the flexible pad separates from the outer wall of the moving lens barrel (6). When the elongation occurs, the flexible pad is pressed against the outer wall of the moving lens barrel (6) and undergoes elastic compression. The first unit (411) and the second unit (412) are tilted in opposite directions.

2. The endoscope focusing adjustment mechanism according to claim 1, characterized in that, The driver (4) also includes a fixed ring (42) and a flexible ring (43). The fixed ring (42) and the flexible ring (43) are both sleeved on the outside of the movable lens tube (6). The outer ends of the first unit (411) and the second unit (412) are fixed on the fixed ring (42), and the inner ends of the first unit (411) and the second unit (412) are fixedly connected to the flexible ring (43).

3. An endoscope focusing adjustment mechanism according to claim 1 or 2, characterized in that, There are multiple first units (411) and second units (412). The first units (411) are evenly distributed in a ring relative to the axis of the moving lens tube (6), and the second units (412) are evenly distributed in a ring relative to the axis of the moving lens tube (6).

4. An endoscope focusing adjustment mechanism according to claim 2, characterized in that, It also includes a base (5) and a connecting ring (7), both of which are cylindrical; The inner wall of the base (5) is provided with a positioning shoulder, the fixing ring (42) is embedded in the base (5) and coaxial with the base (5), one end of the fixing ring (42) is engaged with the positioning shoulder, and the connecting ring (7) is embedded in the base (5) and its end is connected to the other end of the fixing ring (42); The movable lens tube (6) is constrained to be coaxial with the base (5) by contact between its outer wall and the inner wall of the base (5) and / or the connecting ring (7).

5. An endoscope focusing adjustment mechanism according to claim 4, characterized in that, Of the base (5) and the movable lens barrel (6), one is provided with a guide groove (51) parallel to the optical axis of the movable lens barrel (6), and the other is provided with a boss (61). The boss (61) is embedded in the guide groove (51), and the boss (61) and the guide groove (51) form a guiding structure for the movable lens barrel (6) to move relative to the base (5).

6. An endoscope focusing adjustment mechanism according to claim 3, characterized in that, The first unit (411) has a common first power supply unit, which is used to synchronously supply power to each first unit (411); The second unit (412) has a common second power supply unit, which is used to synchronously supply power to each second unit (412).

7. An endoscope focusing adjustment mechanism according to claim 3, characterized in that, Each first unit (411) and second unit (412) is provided with a slot (421) on the inner wall of the fixing ring (42), and the outer ends of each first unit (411) and second unit (412) are embedded in the corresponding slot (421); The flexible ring (43) is provided with flanges (431) coaxial with the flexible ring (43) on both the inner and outer sides; The first unit (411) is distributed on one side of the flange (431) on the outside of the flexible ring (43), and the second unit (412) is distributed on the other side of the flange (431) on the outside of the flexible ring (43); the first unit (411) and the second unit (412) are both located on the side of the flange (431) on the outside of the flexible ring (43); In the axial direction of the flexible ring (43), the flange (431) on the inner side of the flexible ring (43) is an arc-shaped surface that protrudes from the middle towards the side where the axis of the flexible ring (43) is located; The flange (431) on the inner side of the flexible ring (43) is located on the extension line of the polarization direction of the first unit (411) and the second unit (412).

8. A lens assembly comprising the endoscope focusing adjustment mechanism as described in any one of claims 1 to 7.

9. An endoscope comprising the lens assembly as described in claim 8.

10. An endoscopic focusing adjustment method, characterized in that, The method is based on the endoscope focusing adjustment mechanism according to any one of claims 1 to 7. The method is to provide the first unit (411) and the second unit (412) with a voltage that changes in a wave-like manner, so that the first unit (411) and the second unit (412) contract and elongate based on the inverse piezoelectric effect. When the first unit (411) elongates, the flexible pad presses the movable lens barrel (6) to provide thrust to the movable lens barrel (6) and cause the movable lens barrel (6) to move in the first direction; When the second unit (412) elongates, the flexible pad presses the movable lens tube (6) to provide thrust to the movable lens tube (6) and cause the movable lens tube (6) to move in the second direction; The first direction and the second direction are both along the optical axis and are opposite in direction; The displacement of the movable lens tube (6) is adjusted according to the number of times the first unit (411) and / or the second unit (412) provide thrust to the movable lens tube (6).

Images