Lens clamping mechanism and optical equipment

Abstract

The invention relates to the technical field of optics, and particularly provides a lens clamping mechanism and optical equipment, and the lens clamping mechanism comprises an optical lens group, a first lens cone, a second lens cone, and an elastic supporting member, and the two ends of the elastic supporting member are respectively installed on the first lens cone and the second lens cone. The elastic support member is connected to the outer peripheral wall of the first lens cone and the inner peripheral wall of the second lens cone according to a preset angle, and under the supporting effect of the elastic support member, the first lens cone moves in the second lens cone to generate a supporting force in a first direction and generates resistance to a second direction at the same time. The first direction is opposite to the second direction, and the rotation and displacement of the center rod in the plane can be limited through the elastic supporting piece, so that the first lens cone can only be in the direction perpendicular to the plane, and even if the rotation or displacement deviating from the center is generated in the moving process, the first lens cone can be corrected to the original position after the movement is stopped. The single-degree-of-freedom movement mechanism has the advantages of being simple in structure and high in stability.

Description

Technical Field

[0001] The invention relates to the field of optical technology, and in particular provides a lens clamping mechanism and an optical device. Background Art

[0002] In an optical system using a zoom function, it is usually necessary to adjust the position of one or more optical lenses in the system to change the focal length of the entire optical system. This adjustment generally requires that the center of the lens is still on the main optical axis, and only the relative position of the axial direction between the lenses is changed, that is, the lens is required to be displaced only in one degree of freedom, while maintaining stability in other degrees of freedom. In the prior art, there are mainly two types of guide rail control and rotation control. The guide rail control method adjusts the axial position of the lens through the guide rail, but this method has limited restrictions on the degrees of freedom in other directions during the movement, and the track is generally large in size and heavy in weight, easy to wear, and has a limited service life, which is not convenient for use in a portable small lens barrel. The rotation control method usually adopts a method of providing a special type of groove on the inner periphery of the lens barrel to change the position of the lens by rotating the lens barrel. However, when using this method to adjust the lens position, it is necessary to focus and zoom at the same time. Under a limited rotation angle, the number of zoom segments is limited and the flexibility is low. In addition, the method of rotating the lens barrel will amplify the eccentricity error of a single lens, affecting the imaging accuracy of the entire optical system. The prior art mainly includes two types of guide rail control and rotation control. The shortcomings of these two technologies are introduced below.

[0003] Method 1: Use guide rails to achieve high-precision linear motion. Different types of guide rails have different working principles. There are mainly two working modes: Sliding friction guide: This type of guide achieves movement through direct contact between the slider and the guide rail. It has high friction and is not suitable for applications with high precision requirements.

[0004] Rolling friction guide: By placing balls or rollers between the slider and the guide rail, sliding friction is converted into rolling friction, thereby reducing friction and improving movement accuracy and speed. The balls or rollers roll in the wedge-shaped space between the guide rail and the slider, allowing the slider to move more smoothly. However, balls or rollers are often used in conjunction with lubricants, and there is also the possibility of lubricant evaporation in the optical system, causing lens contamination. In addition, most guide rail systems require a whole track to limit and guide the movement of the slider, which requires a larger volume and mass, making it difficult to apply to miniaturized optical systems. In general, the design of the guide rail is intended to improve the performance and accuracy of the mechanical system by minimizing the friction between moving parts. The control of one-way freedom can be maintained to a certain extent through the limitation of the guide rail, but there is a lack of control means for the lens eccentricity caused by factors such as tremor that may occur during movement, and the size is large and not flexible enough.

[0005] The second method is to connect the focusing screw with the lens movement through mechanical components and threads, and realize the axial movement of the lens or lens group by rotating the lens barrel. The common zoom lens can focus by rotating the lens barrel based on this design. Since this movement method requires the rotation of the entire lens, it is very sensitive to the displacement of the optical center, which will amplify the eccentricity error in the optical path and is difficult to apply to aspheric systems. Since the thread and the lens clamping device need to be strictly matched to ensure the alignment of the optical center, the premise of the thread movement is that there is a gap. Therefore, this movement method is often sensitive to vibration and difficult to overcome environmental disturbance factors. At the same time, the thread mechanism will have empty return during repeated focusing, affecting the focusing accuracy. In addition, this method is currently mostly used for camera lens focusing. The card slot is set to control the lens position for several preset focusing schemes. It can only achieve focusing at a specific distance. The system flexibility is limited, and it is difficult to control the displacement of any lens at any distance. Summary of the invention

[0006] In order to solve the above problems, the present invention provides a lens clamping mechanism and an optical device, which have the advantages of simple structure and strong stability, and have strong resistance to optical center deviation occurring during the movement process.

[0007] In a first aspect, the present invention provides a lens clamping mechanism, comprising: An optical lens set, comprising at least one optical lens; A first lens barrel, used to fix the optical lens group, and when the lens needs to be focused, the first lens barrel moves together with the optical lens group; A second lens barrel, serving as a housing of a lens, is used to mount the first lens barrel, the first lens barrel is partially or completely contained in the second lens barrel, and serves as a reference coordinate system when the optical lens group moves; An elastic support member, both ends of which are respectively mounted on the first lens barrel and the second lens barrel, the elastic support member is connected to the outer circumferential wall of the first lens barrel and the inner circumferential wall of the second lens barrel at a preset angle, and under the supporting action of the elastic support member, the first lens barrel moves inside the second lens barrel to generate a supporting force in a first direction and a resistance in a second direction at the same time, and the first direction and the second direction are opposite.

[0008] As a preferred solution, the first direction is a tangent direction along the outer peripheral wall of the first lens barrel.

[0009] As a preferred solution, the elastic support member is a hard spring sheet, and the hard spring sheets have four pieces and are evenly distributed between the first lens barrel and the second lens barrel.

[0010] As a preferred solution, adjacent elastic support members are perpendicular to each other.

[0011] In a second aspect, the present invention provides an optical device having the lens holding mechanism as described above.

[0012] The lens clamping mechanism and optical device provided in the embodiments of the present invention include an optical lens group, a first lens barrel, a second lens barrel, and an elastic support member, wherein two ends of the elastic support member are respectively mounted on the first lens barrel and the second lens barrel, and the elastic support member is connected to the outer peripheral wall of the first lens barrel and the inner peripheral wall of the second lens barrel at a preset angle. Under the support of the elastic support member, the first lens barrel moves in the second lens barrel to generate a supporting force in a first direction and simultaneously generates resistance in a second direction, wherein the first direction is opposite to the second direction. The elastic support member can limit the rotation and displacement of the center rod in the plane, so that the first lens barrel can only be displaced in the direction perpendicular to the plane, i.e., along the optical axis. Even if rotation or displacement off-center occurs during the movement, it can be corrected back to the original position after the movement stops, i.e., movement under single degree of freedom restriction is achieved. The mechanism has the advantages of simple structure and high stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 is a structural schematic diagram of a lens clamping mechanism provided according to an embodiment of the present invention; Figure 2 is a schematic diagram of the limiting effect on the rotation of the first lens barrel in the lens clamping mechanism provided in an embodiment of the present invention; Figure 3 is a schematic diagram of the limiting effect on the displacement of the inner cylinder in the lens clamping mechanism provided according to an embodiment of the present invention; Figure 4 is a schematic diagram of the force applied to the elastic supporting member in the lens clamping mechanism according to an embodiment of the present invention when the first lens barrel undergoes axial displacement; Figure 5 It is a schematic diagram of the axial displacement of the first lens barrel of the lens clamping mechanism provided according to an embodiment of the present invention.

[0014] Reference numerals include: Optical lens group 1, first lens barrel 2, second lens barrel 3, elastic support member 4 DETAILED DESCRIPTION Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the following description, the same modules are represented by the same reference numerals. In the case of the same reference numerals, their names and functions are also the same. Therefore, the detailed description thereof will not be repeated.

[0015] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and do not constitute a limitation of the present invention.

[0016] Combination Figure 1 As shown, an embodiment of the present invention provides a lens clamping mechanism, comprising: Optical lens set 1, including at least one optical lens; A first lens barrel 2, used to fix the optical lens group. When the lens needs to be focused, the first lens barrel moves together with the optical lens group; The second lens barrel 3, serving as a lens housing, is used to mount the first lens barrel 2, wherein the first lens barrel 2 is partially or completely contained in the second lens barrel 3 and serves as a reference coordinate system when the optical lens assembly 1 moves; An elastic support member 4, both ends of which are respectively mounted on the first lens barrel 2 and the second lens barrel 3, and the elastic support member 4 is connected to the outer circumferential wall of the first lens barrel 2 and the inner circumferential wall of the second lens barrel 3 at a preset angle. Under the supporting action of the elastic support member 4, the first lens barrel 2 moves in the second lens barrel 3 to generate a supporting force in a first direction and a resistance in a second direction at the same time, and the first direction and the second direction are opposite.

[0017] In some embodiments, the first direction is a tangential direction along the outer peripheral wall of the first lens barrel 2 .

[0018] In some embodiments, the elastic support member 4 is a hard spring sheet, and the hard spring sheets have four pieces and are evenly distributed between the first lens barrel 2 and the second lens barrel 3 , and adjacent elastic support members 4 are perpendicular to each other.

[0019] In order to facilitate understanding of the working principle of the elastic support member 4, it is introduced.

[0020] The system's ability to limit rotation: Combination Figure 2 As shown in (a), the first lens barrel 2 rotates counterclockwise. At this time, the force analysis of the first lens barrel 2 is as follows: Figure 2 As shown in (b). At this time, the length of the elastic support member 4 is shortened compared to the original state, and there is an inward thrust along the direction of the elastic support member 4. Since the four elastic support members 4 are evenly distributed, the deformation of each elastic support member 4 is consistent. Since the elastic force is proportional to the spring deformation, it can be seen that the forces of the four elastic support members 4 on the first lens barrel 2 are equal in magnitude, but in different directions, and the resultant force is 0.

[0021] The four forces are decomposed into tangential and radial component forces along the first lens barrel 2. The radial resultant forces cancel each other out, and the tangential force provides torque for the first lens barrel 2, generating a clockwise twisting force opposite to its original twisting direction, so that it tends to return to its original state, that is, it can limit the rotation of the first lens barrel 2. The force when the first lens barrel 2 rotates clockwise is the same.

[0022] The system's ability to limit plane displacement: like Figure 3 In (a), the first lens barrel 2 has a slight displacement to the left. The force analysis of the rod at this time is as follows: Figure 3 As shown in (b). The four elastic support members 4 are marked as 1, 2, 3, and 4, respectively, with an elastic coefficient of k, a length of l when not subjected to force, and a displacement of x. Then, the elastic force formula is:

[0023] The angle between F2, F4 and the moving direction satisfy:

[0024] Then the resultant force on the first lens barrel 2 is:

[0025] That is, the resultant force only exists in the displacement direction and is opposite to the displacement direction. That is, the system provides the first lens barrel 2 with a force opposite to the displacement direction to compensate and correct the displacement of the rod, limit the displacement of the first lens barrel 2 from its original position, and limit its degree of freedom in this direction.

[0026] Similarly, when a displacement occurs in a direction perpendicular to the illustrated direction, the system can also provide a force in the opposite direction of the displacement to compensate. Any displacement in the plane can be split into a synthesis of two displacements, one in the illustrated direction and the other in the direction perpendicular to the illustrated direction. Therefore, the device can correct any displacement in the plane and achieve freedom restriction.

[0027] Axial degrees of freedom of the system like Figure 4 As shown in (a), the stress of the spring piece when the inner lens barrel is axially displaced. When the system moves axially, due to the relative displacement of the first lens barrel 2 and the second lens barrel 3, the elastic support member 4 connecting the two will be bent by the force, that is, when the first lens barrel 2 moves upward from the original position, the elastic support member 4 will be deformed. Figure 4 (b) Schematic diagram of the cross section of the spring. Therefore, the bending section coefficient of the elastic support member 4 can be explored to prove the existence of the system's degree of freedom in axial displacement.

[0028] Since there is no normal stress between the longitudinal fibers, each fiber is unidirectionally stretched or compressed, and assuming that the elastic modulus of the material in tension and compression is equal, when the stress does not exceed the proportional limit, Hooke's law gives:

[0029] in is the stress at a certain point, E is the elastic modulus, y is the distance from the point to the neutral axis, is the curvature of the beam axis after deformation. This formula shows that the normal stress at any point on the cross section is proportional to the distance from the point to the neutral axis.

[0030] Considering micro area Micro internal force , which constitutes a spatial parallel force system perpendicular to the cross section. In the case of pure bending, the moment M around the neutral axis x-axis x That is the bending moment of the cross section. According to formula (8), we have:

[0031] in , is the polar moment of inertia. From this we can get:

[0032] in, is the curvature of the beam axis after deformation, EI x It is called the bending stiffness of the cross section. Substituting formula (10) into formula (8), we get:

[0033] This formula is often used to calculate the lateral bending normal stress when the cross section satisfies the ratio of the span to the cross section height of the beam is greater than or equal to 5. The maximum normal stress that maintains its shape unchanged is:

[0034] in is the bending section coefficient, which is related to the geometric shape of the cross section. The cross section of the hard spring in this device is approximately rectangular, and for a rectangle with a cross section height of h and a width of b, W x satisfy:

[0035] Since the cross-sectional span b of the elastic support member 4 is much greater than the height h, the normal stress only needs to be greater than That is, deformation occurs, that is, the first lens barrel 2 is displaced.

[0036] At the same time, since the elastic support member 4 bends and produces elastic deformation, it will exert a force on the first lens barrel 2 to return to its initial position. Therefore, the system requires a matching locking mechanism to enable the first lens barrel 2 to stay stably in a specific position. The specific structure of the locking mechanism is not limited, and the locking function of the mechanism can be realized.

[0037] In summary, the elastic support member 4 can limit the rotation and displacement of the center rod in the plane, so that the first lens barrel 2 can only be displaced in the direction perpendicular to the plane, that is, along the optical axis; even if off-center rotation or displacement occurs during the movement, it can be corrected back to the original position after the movement stops, that is, movement under single-degree-of-freedom restriction is achieved.

[0038] like Figure 5 The figure shows a displacement diagram of the device when focusing, where the first lens barrel 2 moves up and down inside the second lens barrel 3.

[0039] The lens clamping mechanism provided in the embodiment of the present invention comprises an optical lens group 1, a first lens barrel 2, a second lens barrel 3, and an elastic support member 4, wherein two ends of the elastic support member 4 are respectively mounted on the first lens barrel 2 and the second lens barrel 3, and the elastic support member 4 is connected to the outer peripheral wall of the first lens barrel 2 and the inner peripheral wall of the second lens barrel 3 at a preset angle. Under the supporting action of the elastic support member 4, the first lens barrel 2 moves in the second lens barrel 3 to generate a supporting force in a first direction and a resistance in a second direction at the same time, and the first direction is opposite to the second direction. The elastic support member 4 can limit the rotation and displacement of the center rod in the plane, so that the first lens barrel 2 can only be displaced in the direction perpendicular to the plane, that is, along the optical axis. Even if a rotation or displacement off the center occurs during the movement, it can be corrected back to the original position after the movement stops, that is, the movement under the restriction of a single degree of freedom is realized, and the mechanism has the advantages of simple structure and high stability.

[0040] In a second aspect, the present invention provides an optical device having the lens holding mechanism as described above.

[0041] The optical device provided by the present invention has the following advantages: The control operation is simple and flexible, and the optical center of the lens can be stabilized, so that the restriction of non-axial degrees of freedom can be achieved more stably and simply.

[0042] The structure is simple, the weight is light and the volume is small, and it can achieve high lightness, and can be used for more precise, portable and miniaturized zoom systems.

[0043] Long service life. Through the new connection method, there is no backlash and friction, which extends the service life.

[0044] It has strong stability and is highly resistant to optical center deviation during movement. When it deviates from the center due to environmental friction, vibration, etc., it can quickly return to the original center position.

[0045] The present invention is not only aimed at a single-degree-of-freedom movement restriction device, but also can be used for a matching movement propulsion device, a precision metering device, and a displacement locking mechanism, which can be freely modified according to actual conditions without affecting the overall principle and use of the device.

[0046] In addition, the specific shape of the hard support member can be adapted and adjusted according to the specific situation. Under the same principle, the shape of the hard support member does not affect the function of the device, and any shape of the hard support member falls within the scope of protection of this patent.

[0047] In the first lens barrel of the present invention, the lens or lens group can be fixed in any stable manner, and the specific fixing method or the number of fixed lenses does not affect the protection scope of this patent.

[0048] Although the embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and cannot be understood as limiting the present invention. Those skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

[0049] The above specific implementations of the present invention do not constitute a limitation on the protection scope of the present invention. Any other corresponding changes and modifications made based on the technical concept of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A lens clamping mechanism, characterized in that: include: An optical lens set, comprising at least one optical lens; A first lens barrel, used to fix the optical lens group, and when the lens needs to be focused, the first lens barrel moves together with the optical lens group; A second lens barrel, serving as a housing of a lens, is used to mount the first lens barrel, the first lens barrel is partially or completely contained in the second lens barrel, and serves as a reference coordinate system when the optical lens group moves; An elastic support member, both ends of which are respectively mounted on the first lens barrel and the second lens barrel, the elastic support member is connected to the outer circumferential wall of the first lens barrel and the inner circumferential wall of the second lens barrel at a preset angle, and under the supporting action of the elastic support member, the first lens barrel moves inside the second lens barrel to generate a supporting force in a first direction and a resistance in a second direction at the same time, and the first direction and the second direction are opposite.

2. The lens holding mechanism according to claim 1, wherein: The first direction is a tangential direction along the outer peripheral wall of the first lens barrel.

3. The lens holding mechanism according to claim 1, wherein: The elastic support member is a hard spring sheet, and the hard spring sheets have four pieces and are evenly distributed between the first lens barrel and the second lens barrel.

4. The lens holding mechanism according to claim 3, wherein: Adjacent elastic supporting members are perpendicular to each other.

5. An optical device, characterized in that: A lens holding mechanism according to any one of claims 1 to 4 is provided.

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