Optical zoom lens and imaging apparatus

Abstract

The invention discloses an optical zoom lens and camera shooting equipment, and relates to the technical field of optical zoom systems.The optical zoom lens comprises a lens group, a plurality of voice coil motors and a position determining structure, the lens group is movably arranged in the front-back direction, and the voice coil motors are annularly arranged on the peripheral side of the lens group at intervals; each voice coil motor comprises a magnet structure and a magnetic force matching part, the magnet structure forms a magnetic field, and the magnetic force matching part is connected with the lens group and is located in the magnetic field, so that when the magnetic force matching part and the magnet structure generate magnetic force action, the magnetic force matching part drives the lens group to move in the front-back direction relative to the magnet structure; comprising a measuring part and a position determining part, one of the measuring part and the position determining part is fixedly arranged, and the other one is connected with the lens group so as to synchronously move with the lens group. Through the arrangement, the power requirement and noise can be reduced, no abrasion and no out-of-step are achieved, and the position detection precision below 1 micron can be achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of optical zoom systems, and in particular to an optical zoom lens and a camera device. Background Art

[0002] With the rapid development of high-tech, security optical zoom lenses have been widely used, and stepper motors are widely used in the automatic zoom and focus of optical zoom lenses. The existing stepper motor drive method has low speed, high power consumption, susceptibility to electromagnetic interference and noise, and poor wear resistance. At the same time, the existing position sensing method adopts open-loop control, which can only sense one position through PI, has low control accuracy, and is prone to undesirable phenomena such as loss of step.

[0003] The optical zoom lenses currently on the market have poor stability, are greatly affected by magnetic fields and noise, have high energy consumption, are prone to wear, loss of step and other unstable phenomena, and cannot meet the increasingly stringent requirements of today's customers. Summary of the invention

[0004] The main purpose of the present invention is to provide an optical zoom lens and a camera device, aiming to improve the problem of poor zoom stability of the existing optical zoom lens.

[0005] To achieve the above object, the optical zoom lens provided by the present invention comprises: The lens group is movably arranged in the front-rear direction; A plurality of voice coil motors, wherein a spacer ring is disposed on the peripheral side of the lens group, each of the voice coil motors comprises a magnet structure and a magnetic force matching portion, wherein the magnet structure forms a magnetic field, and the magnetic force matching portion is connected to the lens group and is located within the magnetic field, so that when the magnetic force matching portion and the magnet structure generate magnetic force, the magnetic force matching portion drives the lens group to move in a forward and backward direction relative to the magnet structure; and The position determination structure comprises a measuring part and a position determination part, wherein one of the measuring part and the position determination part is fixedly arranged, and the other one is connected to the lens group to move synchronously with the lens group.

[0006] In one embodiment, the magnet structure comprises: A magnetic yoke having a first magnetic yoke and a second magnetic yoke spaced apart in the radial direction of the lens group and extending in the front-rear direction, wherein the first magnetic yoke is disposed close to the lens group; and A magnet, disposed on a side of the second magnetic yoke facing the lens group; The magnetic force matching portion is at least partially located between the first magnetic yoke and the second magnetic yoke.

[0007] In one embodiment, the magnetic yoke further includes a third magnetic yoke extending along the radial direction of the lens group, and two ends of the third magnetic yoke are respectively connected to the first magnetic yoke and the second magnetic yoke.

[0008] In one embodiment, each of the voice coil motors comprises a first induction coil, wherein at least a portion of the first induction coil is located in the magnetic field formed by the corresponding magnet structure, and a winding center is arranged to extend in a front-to-back direction; The portion of each of the first induction coils located in the corresponding magnetic field forms the magnetic force matching portion.

[0009] In one embodiment, the optical zoom lens further comprises a second induction coil, wherein at least a portion of the second induction coil is located in the magnetic field formed by the plurality of magnetic structures, and a winding center thereof is arranged to extend in a front-to-back direction; Portions of the second induction coil located within the plurality of magnetic fields respectively form a plurality of magnetic force matching portions.

[0010] In one embodiment, the measuring part includes a magnetic grid extending in a front-to-rear direction, and the position determining part includes a magnetic sensor movable in a front-to-rear direction relative to the magnetic grid. The magnetic sensor is used to detect changes in the magnetic force of the magnetic grid during its movement to determine the position of the lens group.

[0011] In one embodiment, the optical zoom lens further includes a guide structure, and the guide structure is movably connected to the lens group to guide the movement of the lens group in a front-rear direction.

[0012] In one embodiment, the lens group is provided with a through hole along the front-to-back direction; The guiding structure comprises: Mounting base, fixed arrangement; and, A guide rod is arranged on the mounting seat and extends in a front-rear direction, and the guide rod passes through the through hole to be slidably matched with the through hole.

[0013] In one embodiment, the optical zoom lens further includes a lens barrel, and the lens barrel is extended in a front-to-back direction; The magnetic structure is fixedly installed in the lens barrel, and one of the measuring part and the position determining part is fixedly connected to the lens barrel.

[0014] The present invention also provides a camera device, wherein the device comprises the above-mentioned optical zoom lens.

[0015] In the technical solution of the present invention, when the plurality of magnetic force matching parts are energized, the magnetic fields generated by the plurality of magnetic force matching parts interact with the magnetic fields of the corresponding magnetic structures, so that the plurality of magnetic force matching parts can move in the front-to-back direction relative to the corresponding magnetic structures. Furthermore, because the plurality of magnetic force matching parts are all connected to the lens group, when the plurality of magnetic force matching parts move in the front-to-back direction, the lens group also moves synchronously in the front-to-back direction to achieve the zooming of the optical zoom lens. At the same time, during the movement of the lens group in the front-to-back direction, one of the measuring part and the position determining part also moves synchronously with the lens group. At this time , the corresponding measuring unit and the position determination unit adopt a closed-loop control method to detect the position of the lens group in real time during the movement of the lens group in the forward and backward directions, and adjust the position of the lens group in real time according to the displacement difference between the actual position of the lens group and the target position, without being limited by the physical accuracy and wear accuracy of the voice coil motor itself, and when multiple voice coil motors drive the moving group to move at high speed, they will not be affected by the difference in stopping accuracy, so that the lens group can accurately reach the target position required for zooming or focusing, so as to realize multi-position sensing detection and accurately sense any position driven by the voice coil motor. In this way, through the setting of multiple voice coil motors, the power requirement of a single voice coil motor when driving the lens group to move is reduced, and the noise is reduced, so as to achieve no wear and no step loss, and through the cooperation of multiple voice coil motors and the position determination structure, the position detection accuracy of less than 1um is achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0017] Figure 1 A schematic structural diagram of an embodiment of an optical zoom lens provided by the present invention; Figure 2 A schematic structural diagram of another embodiment of the optical zoom lens provided by the present invention; Figure 3 for Figure 2 Schematic diagram of the structure of the lens barrel of the medium optical zoom lens.

[0018] Description of Figure Numbers: 100. Optical zoom lens; 1. Lens group; 2. Voice coil motor; 21. Magnet structure; 211. Yoke; 211a. First yoke; 211b. Second yoke; 211c. Third yoke; 212. Magnet; 22. Magnetic matching part; 23. First induction coil; 24. Second induction coil; 3. Position determination structure; 31. Measuring part; 311. Magnetic grid; 32. Position determination part; 321. Magnetic sensor; 4. Guide structure; 41. Guide rod; 5. Lens barrel.

[0019] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0022] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features limited to "first" and "second" may explicitly or implicitly include at least one of the features. In addition, if "and / or" or "and / or" appears in the full text, its meaning includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or solutions that satisfy both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0023] The present invention provides an optical zoom lens, aiming to improve the problem of poor zoom stability of the existing optical zoom lens.

[0024] See also Figure 1In one embodiment of the present invention, the optical zoom lens 100 includes a lens group 1, a plurality of voice coil motors 2, and a position determination structure. The lens group 1 is movably arranged in a front-to-back direction. The plurality of voice coil motors 2 are arranged in a spacer ring around the lens group 1. Each of the voice coil motors 2 includes a magnet structure 21 and a magnetic force matching portion 22. The magnet structure 21 forms a magnetic field. The magnetic force matching portion 22 is connected to the lens group 1 and is located in the magnetic field. When the magnetic force matching portion 22 and the magnet structure 21 generate magnetic force, the magnetic force matching portion 22 drives the lens group 1 to move in a front-to-back direction relative to the magnet structure 21. The position determination structure 3 includes a measuring portion 31 and a position determination portion 32. One of the measuring portion 31 and the position determination portion 32 is fixedly arranged, and the other is connected to the lens group 1 to move synchronously with the lens group 1.

[0025] In the technical solution of the present invention, when the plurality of magnetic force matching parts 22 are energized, the magnetic fields generated by the plurality of magnetic force matching parts 22 interact with the magnetic fields of the corresponding magnetic structures 21, so that the plurality of magnetic force matching parts 22 can move in the front-to-back direction relative to the corresponding magnetic structures 21. Moreover, because the plurality of magnetic force matching parts 22 are all connected to the lens group 1, when the plurality of magnetic force matching parts 22 move in the front-to-back direction, the lens group 1 also moves in the front-to-back direction synchronously to achieve the zooming of the optical zoom lens 100. Meanwhile, during the movement of the lens group 1 in the front-to-back direction, one of the measuring part 31 and the position determining part 32 is also connected to the lens group 1. The lens group 1 is synchronously moved. At this time, the corresponding measuring unit 31 and the position determination unit 32 adopt a closed-loop control method to detect the position of the lens group 1 in real time during the movement of the lens group 1 in the forward and backward directions, and adjust the position of the lens group 1 in real time according to the displacement difference between the actual position of the lens group 1 and the target position, which is not limited by the physical accuracy and wear accuracy of the voice coil motor 2 itself, and when multiple voice coil motors 2 drive the moving group to move at high speed, they will not be affected by the difference in stopping accuracy, so that the lens group 1 can accurately reach the target position required for zooming or focusing, so as to realize multi-position sensing detection and accurately sense any position driven by the voice coil motor 2. In this way, through the setting of multiple voice coil motors 2, the power requirement of a single voice coil motor 2 when driving the lens group 1 to move is reduced, and the noise is reduced, so as to achieve no wear and no step loss, and through the cooperation of multiple voice coil motors 2 and the position determination structure 3, the position detection accuracy of less than 1um is achieved.

[0026] It should be noted that the present invention does not limit the specific number of the voice coil motors 2. In one embodiment of the present invention, the number of the voice coil motors 2 is two, and the two voice coil motors 2 are arranged on two opposite sides of the lens group 1 in the radial direction to ensure the stability of the two voice coil motors 2 driving the lens group 1.

[0027] In another embodiment of the present invention, four voice coil motors 2 are provided, and four spacer rings of the voice coil motors 2 are provided on the circumference of the lens group 1, and the distance between any two adjacent voice coil motors 2 is equal. In this way, the stability of driving the lens group 1 can also be ensured, and the provision of a larger number of voice coil motors 2 can further reduce the output power required by a single motor to drive the lens group 1 to move in the forward and backward directions, thereby further reducing the power demand and noise of a single voice coil motor 2.

[0028] Of course, in other embodiments of the present invention, the number of the voice coil motors 2 may also be set to other numbers. Specifically, the present invention does not limit this. In actual settings, it can be selected according to needs.

[0029] Specifically, in this embodiment, the number of the voice coil motors 2 is set to four.

[0030] Further, in an embodiment of the present invention, the magnetic structure 21 includes a yoke 211 and a magnet 212, the yoke 211 includes a first yoke 211a and a second yoke 211b which are spaced apart in the radial direction of the lens group 1 and are extended in the front-back direction, the first yoke 211a is arranged close to the lens group 1, the magnet 212 is arranged on the side of the second yoke 211b facing the lens group 1, and the magnetic force matching portion 22 is at least partially located between the first yoke 211a and the second yoke 211b. In this way, the first yoke 211a and the second yoke 211b can jointly limit the magnetic force lines of the magnet 212 between the first yoke 211a and the second yoke 211b, thereby ensuring that the magnet 212 can form a closed magnetic circuit to provide a low magnetic resistance path, so that the magnetic force lines can flow more effectively, thereby increasing the strength and stability of the magnetic field.

[0031] Furthermore, since the magnet 212 is disposed on the side of the second magnetic yoke 211 b facing the lens group 1 , such a configuration can limit the loss of the magnetic field of the magnet 212 in the radial direction of the lens group 1 , thereby improving the utilization rate of the magnetic field in the radial direction of the lens group 1 .

[0032] Meanwhile, the magnetic yoke 211 further comprises a third magnetic yoke 211c extending in the radial direction of the lens group 1, and the two ends of the third magnetic yoke 211c are respectively connected to the first magnetic yoke 211a and the second magnetic yoke 211b. The third magnetic yoke 211c can further concentrate the magnetic field to further improve the effect of the electromagnetic force. Meanwhile, the third magnetic yoke 211c can connect the first magnetic yoke 211a and the second magnetic yoke 211b, thereby ensuring the structural stability of the magnetic yoke 211.

[0033] In addition, by designing and matching the shape and size of the yoke 211, the magnetic field lines can be made to pass through the target area more concentratedly, enhancing the range and effect of the magnetic force, thereby improving the efficiency and performance of the voice coil motor 2. Through the close connection with the magnet 212, the yoke 211 can directly transfer the magnetic force generated by the magnetic field to the lens group 1 to achieve force transmission and drive. The presence of the yoke 211 can reduce the leakage and loss of the magnetic field to improve the transmission efficiency of the magnetic force. In addition, by fixing and supporting the magnet, the yoke 211 can prevent the displacement and distortion of the magnetic field, maintain the stability and consistency of the magnetic field, and improve the stability and reliability of the system.

[0034] It should also be noted that the present invention does not limit the specific material of the yoke 211. In one embodiment of the present invention, the material of the yoke 211 can be set to sodium perovskite material, which has excellent magnetic permeability and low hysteresis loss, and can effectively reduce the energy loss of the magnetic field; in another embodiment of the present invention, the material of the yoke 211 can also be set to ferrite material. Such a setting can also ensure that the yoke 211 has good magnetic properties and high magnetic induction intensity.

[0035] In other embodiments of the present invention, the material of the yoke 211 can also be set to nickel-iron alloy material, iron-based soft magnetic material or other materials. When setting it specifically, it can be selected according to needs, and the present invention does not limit this.

[0036] Of course, the present invention also does not limit the specific material of the magnet 212. In one embodiment of the present invention, the magnet 212 can be set to a neodymium iron boron magnet 212; in another embodiment of the present invention, the material of the magnet 212 can also be set to a cobalt boron magnet; and in other embodiments of the present invention, the material of the magnet 212 can also be set to an aluminum nickel cobalt magnet, a soft magnet or other magnets. The above materials are all strong magnet materials. It can be understood that different materials have different characteristics and application ranges. The specific selection needs to be comprehensively considered according to the magnetic field strength requirements, operating temperature range, long-term stability and other factors of the voice coil motor 2. In actual settings, it is usually necessary to select the most suitable material according to specific needs.

[0037] Furthermore, in order to ensure that the magnetic force matching part 22 can generate an electromagnetic effect with the magnetic structure 21, thereby driving the lens group 1 to move in the front-to-back direction, in one embodiment of the present invention, each of the voice coil motors 2 includes a first induction coil 23, at least part of the first induction coil 23 is located in the magnetic field formed by the corresponding magnetic structure 21, and the winding center is arranged to extend in the front-to-back direction, and the part of each of the first induction coils 23 located in the corresponding magnetic field forms the magnetic force matching part 22. In this way, when the first induction coil 23 is energized, the generated magnetic field interacts with the magnetic structure 21, so that the first induction coil 23 can move relative to the magnetic structure 21 in the front-to-back direction, so as to drive the lens group 1 to move in the front-to-back direction, thereby realizing the position adjustment of the lens group 1.

[0038] In a further embodiment of the present invention, in order to ensure that the magnetic structure 21 can always generate a positive driving force on the first induction coil 23, thereby ensuring the movement of the first induction coil 23, in this embodiment, the first induction coil 23 is sleeved on the outer ring of the first magnetic yoke 211a, and is at least partially located between the first magnetic yoke 211a and the second magnetic yoke 211b.

[0039] Of course, the present invention does not limit the connectivity relationship between the multiple first induction coils 23. In one embodiment of the present invention, the multiple first induction coils 23 are connected to a power supply, and the multiple first induction coils 23 are arranged in parallel. In this way, when it is necessary to energize the multiple first induction coils 23 to drive the lens group 1 to move in the forward and backward directions, the power supply supplies power so that the multiple first induction coils 23 can interact with the corresponding magnetic structure 21 at the same time, and the magnetic forces of the magnetic fields generated by the multiple first induction coils 23 are also equal.

[0040] In another embodiment of the present invention, each of the first induction coils 23 can also be connected to a power supply, so that any two of the first induction coils 23 are independent of each other. When it is necessary to energize multiple first induction coils 23 to drive the lens group 1 to move in the front-to-back direction, multiple power supplies are supplied together to enable the corresponding first induction coils 23 to interact with the corresponding magnetic structure 21. In this way, any two of the first induction coils 23 are independent of each other. When any of the first induction coils 23 fails to short-circuit or open-circuit, the other first induction coils 23 can continue to work normally, and the magnitude of the magnetic field generated by the other first induction coils 23 will not be affected. The lens group 1 can still move stably in the front-to-back direction, thereby ensuring the stability of zooming or focusing of the optical zoom lens 100.

[0041] In addition, the present invention does not limit the specific structural form of the magnetic force matching part 22. In another embodiment of the present invention, the optical zoom lens 100 further includes a second induction coil 24. The second induction coil 24 is at least partially located in the magnetic field formed by the plurality of magnetic structures 21, and the winding center thereof is arranged to extend in the front-to-back direction. The portions of the second induction coil 24 located in the plurality of magnetic fields respectively form a plurality of magnetic force matching parts 22. In this arrangement, only one induction coil is arranged to interact with the plurality of magnetic structures 21 at the same time, so that the second induction coil 24 can move relatively in the front-to-back direction under the drive of the plurality of magnetic structures 21, so as to drive the lens group 1 to move in the front-to-back direction, thereby realizing the position adjustment of the lens group 1.

[0042] It can be understood that when only one second induction coil 24 is provided, when the second induction coil 24 is energized, the magnetic field generated by the second induction coil 24 can interact with the plurality of magnetic structures 21 at the same time. Since the currents of various parts of the second induction coil 24 are equal in magnitude, when the second induction coil 24 is energized, the forces of interaction between the magnetic field generated by the second induction coil 24 and the plurality of magnetic structures 21 are equal. In this way, the lens group 1 can achieve stable forward, backward and upward movement.

[0043] It should also be noted that the second induction coil 24 has a smaller resistivity. The setting of the second induction coil 24 can enable the multiple voice coil motors 2 to have a smaller heat generation when working at rated power, thereby further improving the stability of the multiple voice coil motors 2 driving the lens group 1.

[0044] In addition, in one embodiment of the present invention, the measuring unit 31 includes a magnetic grid 311, and the magnetic grid 311 is extended in the front-back direction. The position determining unit 32 includes a magnetic sensor 321, and the magnetic sensor 321 is movably arranged in the front-back direction relative to the magnetic grid 311. The magnetic sensor 321 is used to detect the change of the magnetic force of the magnetic grid 311 during its movement to determine the position of the lens group 1. In this way, the position of the magnetic sensor 321 relative to the magnetic grid 311 can indirectly reflect the position of the lens group 1. Through the relative movement between the magnetic sensor 321 and the magnetic grid 311, the actual position of the lens group 1 can be accurately detected.

[0045] It should be noted that in the present invention, the magnetic grid 311 includes a plurality of magnetic signal bars arranged in a forward and backward manner, and the spacing between any two adjacent magnetic signal bars is equal, and the polarities are arranged in an alternating manner. The magnetic sensor 321 includes two types: a dynamic magnetic sensor 321 (speed-responsive magnetic sensor 321) and a static magnetic sensor 321 (flux-responsive magnetic sensor 321). The dynamic magnetic sensor 321 has an output winding, and can only output a signal when the magnetic sensor 321 and the magnetic grid 311 produce relative motion. The static magnetic sensor 321 has two windings, an excitation winding and an output winding, and can also output a signal when it is relatively stationary with the magnetic grid 311. The static magnetic sensor 321 is a multi-gap iron core with unequal effective cross-sections stacked with iron-nickel alloy sheets. The excitation winding acts as a magnetic switch. When an alternating current is applied to it, the magnetic circuit section with a smaller cross-section of the iron core is excited twice a week to produce magnetic saturation, so that the magnetic lines of force generated by the magnetic grid 311 cannot pass through the iron core. Only when the excitation current passes through zero twice a week, the core is not saturated and the magnetic lines of force of the magnetic grid 311 can pass through the core. At this time, the output winding has an induced potential output. Its frequency is twice the frequency of the excitation current, and the amplitude of the output voltage is proportional to the magnetic flux entering the core, that is, it is related to the position of the magnetic sensor 321 relative to the magnetic grid 311. The purpose of making the magnetic sensor 321 with multiple gaps is to increase the output, and its output signal is the average value of the signals obtained by multiple gaps, so the output accuracy can be improved.

[0046] Of course, the present invention does not limit the specific activities of the magnetic grid 311 and the magnetic sensor 321. In one embodiment of the present invention, the magnetic grid 311 is fixed, and the magnetic sensor 321 moves in the front-to-back direction relative to the magnetic grid 311; in another embodiment of the present invention, the magnetic sensor 321 is fixed, and the magnetic grid 311 moves in the front-to-back direction relative to the magnetic sensor 321.

[0047] In addition, in order to further improve the angle accuracy of the lens group 1 during the front-to-back movement, in one embodiment of the present invention, the optical zoom lens 100 further includes a guide structure 4, which is movably connected to the lens group 1 to guide the movement of the lens group 1 in the front-to-back direction. The setting of the guide structure 4 can further limit the specific movement angle of the lens group 1 in the front-to-back and upward directions, so as to avoid position deviation of the lens group 1 during the movement in the front-to-back direction, thereby affecting the imaging effect of the optical zoom lens 100.

[0048] It should be noted that the present invention does not limit the specific structural form of the guide structure 4. In one embodiment of the present invention, the lens group 1 is provided with a through hole in the front-to-back direction, and the guide structure 4 includes a mounting seat and a guide rod 41. The mounting seat is fixedly arranged, and the guide rod 41 is extended in the front-to-back direction and arranged on the mounting seat, and the guide rod 41 passes through the through hole to slide with the through hole. With such an arrangement, when the lens group 1 moves in the front-to-back direction, the guide rod 41 can limit the specific moving direction of the lens group 1 to avoid position deviation of the lens group 1 during the moving process.

[0049] In another embodiment of the present invention, the guide structure 4 can also be configured as a linear guide rail extending in the front-to-back direction, the linear guide rail is fixedly arranged, and a slider is arranged on the lens group 1 corresponding to the linear guide rail, and the slider is slidably connected to the linear guide rail along a first direction. In this configuration, the cooperation between the linear guide rail and the slider can also limit the specific movement direction of the lens group 1, so that the lens group 1 can move accurately in the front-to-back direction to avoid position deviation.

[0050] Similarly, the present invention does not limit the number of the guide structures 4. In one embodiment of the present invention, one guide structure 4 may be provided; and in another embodiment of the present invention, a plurality of guide structures 4 may be provided, and the plurality of guide structures 4 are spaced apart on the circumference of the lens group 1, and the plurality of guide structures 4 may also jointly locate the movable angle of the lens group 1 to further accurately determine the movable direction of the lens group 1.

[0051] Of course, in order to ensure the working environment of the voice coil motor 2 and to prevent the lens group 1 from being affected by the environment and causing activity deviation during the activity, in a further embodiment of the present invention, the optical zoom lens 100 further includes a lens barrel 5, which is arranged to extend in the front-back direction, the magnetic structure 21 is fixedly installed in the lens barrel 5, and one of the measuring part 31 and the position determining part 32 is fixedly connected to the lens barrel 5. In this way, the setting of the lens barrel 5 provides an installation reference for at least one of the three of the magnetic structure 21, the measuring part 31 and the position determining part 32, so as to ensure the working stability of the voice coil motor 2 and the position determining structure 3.

[0052] The present invention further proposes a camera device, which includes an optical zoom lens 100. The specific structure of the optical zoom lens 100 refers to the above-mentioned embodiment. Since the camera device adopts all the technical solutions of all the above-mentioned embodiments, it at least has all the beneficial effects brought by the technical solutions of the above-mentioned embodiments, which will not be described one by one here.

[0053] The above description is only an exemplary embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the technical concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. An optical zoom lens, characterized in that: include: The lens group is movably arranged in the front-rear direction; A plurality of voice coil motors, wherein a spacer ring is disposed on the peripheral side of the lens group, each of the voice coil motors comprises a magnet structure and a magnetic force matching portion, wherein the magnet structure forms a magnetic field, and the magnetic force matching portion is connected to the lens group and is located within the magnetic field, so that when the magnetic force matching portion and the magnet structure generate magnetic force, the magnetic force matching portion drives the lens group to move in a forward and backward direction relative to the magnet structure; and The position determination structure comprises a measuring part and a position determination part, wherein one of the measuring part and the position determination part is fixedly arranged, and the other one is connected to the lens group to move synchronously with the lens group.

2. The optical zoom lens according to claim 1, wherein: The magnet structure comprises: A magnetic yoke having a first magnetic yoke and a second magnetic yoke spaced apart in the radial direction of the lens group and extending in the front-rear direction, wherein the first magnetic yoke is disposed close to the lens group; and A magnet, disposed on a side of the second magnetic yoke facing the lens group; The magnetic force matching portion is at least partially located between the first magnetic yoke and the second magnetic yoke.

3. The optical zoom lens according to claim 2, wherein: The magnetic yoke further includes a third magnetic yoke extending along the radial direction of the lens group, and two ends of the third magnetic yoke are respectively connected to the first magnetic yoke and the second magnetic yoke.

4. The optical zoom lens according to claim 1, wherein: Each of the voice coil motors comprises a first induction coil, wherein at least a portion of the first induction coil is located in the magnetic field formed by the corresponding magnet structure, and a winding center is arranged to extend in a front-to-back direction; The portion of each of the first induction coils located in the corresponding magnetic field forms the magnetic force matching portion.

5. The optical zoom lens according to claim 1, wherein: The optical zoom lens further includes a second induction coil, wherein at least a portion of the second induction coil is located in the magnetic field formed by the plurality of magnetic structures, and a winding center thereof is arranged to extend in a front-to-back direction; Portions of the second induction coil located within the plurality of magnetic fields respectively form a plurality of magnetic force matching portions.

6. The optical zoom lens according to claim 1, wherein: The measuring part includes a magnetic grid, which is extended in the front-to-back direction. The position determining part includes a magnetic sensor, which is movable relative to the magnetic grid in the front-to-back direction. The magnetic sensor is used to detect the change of the magnetic force of the magnetic grid during its movement to determine the position of the lens group.

7. The optical zoom lens according to claim 1, wherein: The optical zoom lens further comprises a guide structure, which is movably connected to the lens group to guide the movement of the lens group in the front-rear direction.

8. The optical zoom lens according to claim 7, wherein: The lens group is provided with a through hole along the front-to-back direction; The guiding structure comprises: Mounting base, fixed arrangement; and, A guide rod is arranged on the mounting seat and extends in a front-rear direction, and the guide rod passes through the through hole to be slidably matched with the through hole.

9. The optical zoom lens according to claim 1, wherein: The optical zoom lens further comprises a lens barrel, which is arranged to extend in the front-rear direction; The magnetic structure is fixedly installed in the lens barrel, and one of the measuring part and the position determining part is fixedly connected to the lens barrel.

10. A camera device, characterized in that: Comprising the optical zoom lens as claimed in any one of claims 1 to 9.

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