Focusing device and projection device
By employing a focusing design that prevents the lens body from rotating and magnetic sensor detection technology in the projector, the problems of lens wear and focus shift have been solved, resulting in extended lens life, dust and moisture protection, and improved focusing accuracy.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-03
- Publication Date
- 2026-03-24
AI Technical Summary
The relative rotation between the lens and the lens barrel in existing projectors leads to accelerated wear, shortened lifespan, and easy focus shift due to shaking, affecting image clarity and stability.
The focusing mechanism employs a design where the lens body does not rotate during extension and retraction. The focusing component drives the lens body to move along the optical axis, and a magnetic sensor detects magnetic signals to achieve focusing, thus avoiding rotation of the lens and lens barrel. The focusing position is detected by combining the positional relationship between the magnetic component and the magnetic sensor.
It reduces wear and tear on the lens and barrel, extends service life, improves dust and moisture resistance, enhances focusing accuracy and stability, reduces the risk of focus shift during transportation, and improves the reliability of the projection device.
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Figure CN224035686U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the field of projection technology, in particular to a focusing device and a projection device. BACKGROUND
[0002] The working principle of a projector is to irradiate light onto an image display element to generate an image, and then project the image through a lens. When the projector projects different sizes of images, the required focal length is also different. If the focal length is incorrect, the image will be blurred.
[0003] In related technologies, a projection lens includes a lens barrel and a lens body arranged in the lens barrel in a telescopic manner. The lens barrel and the lens body are rotationally coupled. When focusing is required, the lens body is driven to rotate relative to the lens barrel, so that the lens body moves along the axial direction while rotating, thereby achieving focusing.
[0004] However, the relative rotation between the lens and the lens barrel accelerates wear and reduces the service life. Utility model content
[0005] The embodiments of the present application provide a focusing device and a projection device. The lens body does not rotate when being telescoped, so that the wear between the lens body and the focusing lens barrel is relatively small, and the service life is relatively long.
[0006] In a first aspect, the embodiments of the present application provide a focusing device. The focusing device includes a focusing lens, a focusing member, a magnetic member, and a magnetic sensor. The focusing lens includes a focusing lens barrel and a lens body. The lens body has an optical axis and is movably arranged in the focusing lens barrel along the extension direction of the optical axis. The focusing member is rotationally arranged in the focusing lens barrel around the optical axis and is in transmission cooperation with the lens body. The focusing member can drive the lens body to move along the extension direction of the optical axis when the focusing member rotates, and the lens body does not rotate relative to the focusing lens barrel. The magnetic sensor is used to detect the magnetic signal of the magnetic member. One of the magnetic member and the magnetic sensor is fixedly arranged relative to the focusing member, and the other of the magnetic member and the magnetic sensor is fixedly arranged relative to the focusing lens barrel.
[0007] Secondly, embodiments of this application provide a focusing device, which includes a focusing lens, a focusing component, a magnetic component, and a magnetic sensor. The focusing lens includes a focusing lens barrel and a lens body. The lens body has an optical axis and is movably disposed on the focusing lens barrel along the extension direction of the optical axis. The focusing component is rotatably disposed on the focusing lens barrel around the optical axis and is in transmission cooperation with the lens body. When the focusing component rotates, it can drive the lens body to move along the extension direction of the optical axis, and the lens body does not rotate relative to the focusing lens barrel. The magnetic sensor is used to detect the magnetic signal of the magnetic component. One of the magnetic component and the magnetic sensor is fixedly disposed relative to the lens body, and the other of the magnetic component and the magnetic sensor is fixedly disposed relative to the focusing lens barrel.
[0008] Thirdly, embodiments of this application provide a projection device, which includes a focusing device and an optical component, wherein the lens body is disposed on the light-emitting side of the optical component.
[0009] Beneficial effects: In this embodiment of the focusing device, the lens body does not rotate relative to the focusing barrel during focusing, thereby reducing wear between the lens body and the focusing barrel and extending its service life. The gap between the lens body and the focusing barrel can be smaller, minimizing the entry of dust and liquid, and improving dust and moisture resistance. Furthermore, the focusing device is more stable during transportation or movement, and less prone to focus shift due to shaking. Attached Figure Description
[0010] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0011] Figure 1 This is a schematic diagram of the focusing device in one embodiment of this application;
[0012] Figure 2 This is a schematic diagram of the focusing device in another embodiment of this application;
[0013] Figure 3 This is a schematic diagram of the focusing device in another embodiment of this application;
[0014] Figure 4 This is a schematic diagram of the focusing device in another embodiment of this application;
[0015] Figure 5 This is a block diagram of a focusing device in one embodiment of this application.
[0016] Explanation of reference numerals: 100, focusing device; 110, focusing lens; 111, focusing lens barrel; 112, lens body; 120, focusing member; 120a, helical groove; 130, magnetic member; 140, magnetic inductor; 150, driving member; 160, distance inductor; 170, control module; 180, transmission member; AA, optical axis. DETAILED DESCRIPTION
[0017] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.
[0018] It should be noted that all directionality indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present application are only used to explain the relative positional relationship, movement condition, etc. between components in a certain posture (as shown in the drawings), and if the certain posture changes, the directionality indications also change accordingly.
[0019] In addition, the description such as "first", "second" and the like in the present application is only for the purpose of description, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise explicitly specified.
[0020] In the present application, unless otherwise explicitly specified and limited, the terms "connection", "fixation" and the like should be understood broadly, for example, "fixation" can be fixed connection, or detachable connection, or integral; can be mechanical connection, or electrical connection; can be direct connection, or indirect connection through intermediate medium; can be internal connection of two elements or interaction relationship between two elements, unless otherwise explicitly limited. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.
[0021] In addition, the technical solutions of each embodiment of the present application can be combined with each other, but it must be based on the fact that those skilled in the art can realize it, and when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, nor is it within the scope of protection claimed by the present application.
[0022] As Figures 1-4As shown, the first aspect of the embodiment provides a focusing device 100, which comprises a focusing lens 110, a focusing member 120, a magnetic member 130 and a magnetic inductor 140.
[0023] The focusing lens 110 comprises a focusing lens barrel 111 and a lens body 112, and the lens body 112 has an optical axis AA, i.e. an axis passing through the center of the lens body 112. The lens body 112 is movably arranged in the focusing lens barrel 111 along the extension direction of the optical axis AA. Optionally, the focusing lens barrel 111 is sleeved outside the lens body 112, and the lens body 112 is telescopically inserted into the focusing lens barrel 111, so that the lens body 112 can move along the extension direction of the optical axis AA relative to the focusing lens barrel 111. An optical lens group is installed in the lens body 112, and the focusing of the focusing lens 110 can adjust the definition of the projected image.
[0024] The focusing member 120 is rotatably arranged in the focusing lens barrel 111 around the optical axis AA, and the focusing member 120 is exemplarily ring-shaped, so as to be more fitted with the focusing lens barrel 111 and occupy less space. The rotation angle of the focusing member 120 is exemplarily 40°-120°.
[0025] The focusing member 120 is in transmission cooperation with the lens body 112, and the rotation of the focusing member 120 can drive the lens body 112 to move along the optical axis AA. It should be noted that, in the embodiment, the rotation of the focusing member 120 is converted into the linear movement of the lens body 112, so that the lens body 112 does not rotate relative to the focusing lens barrel 111.
[0026] The focusing device 100 of the embodiment can make the lens body 112 not rotate relative to the focusing lens barrel 111 during focusing, so that the wear between the lens body 112 and the focusing lens barrel 111 is relatively small, the service life is relatively long, and the device is more silent. The gap between the lens body 112 and the focusing lens barrel 111 can be smaller, which can prevent dust and liquid from entering the inside as much as possible, improve the dustproof and moisture-proof ability, and the optical axis AA is not easy to deviate when the lens body 112 moves, so that the focusing accuracy is higher. Moreover, the focusing device 100 is more stable during transportation or movement, and is not easy to deviate from focusing due to shaking.
[0027] In addition, since the lens in the lens barrel is difficult to be machined into an absolutely circular shape, the rotation of the lens body 112 relative to the focusing lens barrel 111 will change the optical effect, thereby affecting the projection effect. The focusing device 100 of the embodiment has stable optical effect.
[0028] For example, the focusing member 120 is a ring-shaped member, and the magnetic member 130 is a magnetic ring. Figures 1-4As shown, in some embodiments, the focusing member 120 is provided with a spiral groove 120a. The spiral groove 120a has an axis and extends spirally around the axis. The axis of the spiral groove 120a coincides with the optical axis AA. The focusing device 100 also includes a transmission member 180, which is connected to the lens body 112 and slidably disposed in the spiral groove 120a. The spiral groove 120a has a tendency to extend in the rotational direction around the optical axis AA, and also has a tendency to extend in the extension direction along the optical axis AA. That is, the extension direction of the spiral groove 120a has a component along the optical axis AA. Therefore, when the focusing member 120 rotates, the groove wall of the spiral groove 120a will push the transmission member 180 to move in the extension direction along the optical axis AA, that is, the rotation of the focusing member 120 can be converted into the linear movement of the lens body 112. It should be noted that the spiral groove 120a does not have to extend a full circle around the axis. For example, the spiral groove 120a can extend one-fifth of a circle around the axis. The specific length of the spiral groove 120a can be set according to actual needs and is not limited here.
[0029] Optionally, the transmission component 180 may be located inside the spiral groove 120a or flush with the spiral groove 120a, thereby preventing the transmission component 180 from extending outside the spiral groove 120a and rubbing against other components.
[0030] In other embodiments, the focusing element 120 and the lens body 112 are connected by a thread, which can also convert the rotation of the focusing element 120 into the linear movement of the lens body 112. For example, the inner wall of the focusing element 120 is provided with an internal thread, and the outer wall of the lens body 112 is provided with an external thread. The internal thread of the focusing element 120 and the external thread of the lens body 112 are engaged, so that the rotation of the focusing element 120 can drive the movement of the lens body 112. Of course, the transmission and engagement method between the focusing element 120 and the lens body 112 can also be other existing methods, which are not limited here.
[0031] like Figures 1-4 As shown, in some embodiments, the focusing device 100 further includes a magnetic element 130 and a magnetic sensor 140, wherein the magnetic element 130 has a magnetic field and the magnetic sensor 140 is used to detect the magnetic signal of the magnetic element 130.
[0032] Based on the principle of magnetic field attenuation over distance, different magnetic signals B are sensed by the magnetic sensor 140 when the relative positions of the magnetic component 130 and the magnetic sensor 140 are different. The magnetic sensor 140 is used to determine its relative position with the magnetic component 130 based on the intensity of the sensed magnetic signal B.
[0033] The focusing device 100 has a movable component and a stationary component, and the movable component generates relative motion with respect to the stationary component during focusing. By arranging one of the magnetic element 130 and the magnetic inductor 140 on the movable component and the other on the stationary component, the relative displacement between the magnetic element 130 and the magnetic inductor 140 can be generated. When the distance between the magnetic element 130 and the magnetic inductor 140 is different, the magnetic signal of the magnetic element 130 detected by the magnetic induction is also different. By detecting the magnetic signal of the magnetic element 130, the relative positional relationship between the movable component and the stationary component can be obtained, so that the focusing is realized.
[0034] Specifically, in the actual focusing process, first, the distance d of the focusing lens barrel 111 to the projection surface needs to be obtained. The distance d and the position t of the lens body 112 have a mapping relationship, which is related to the lens group structure of the focusing lens 110 and can be obtained by measurement or theoretical calculation. Through the mapping relationship between the distance d and the position t of the lens body 112, the position t of the lens body 112 corresponding to the clearest projection picture when the distance of the focusing lens barrel 111 to the projection surface is d can be obtained.
[0035] However, the position of the lens body 112 also has a mapping relationship with the magnetic signal B sensed by the magnetic inductor 140, which can also be obtained by actual measurement or theoretical calculation. Therefore, the distance d of the focusing lens barrel 111 to the projection surface has a mapping relationship with the magnetic signal B sensed by the magnetic inductor 140.
[0036] In the related art, the inductive technology of the optical coupling is used to determine the rotation angle of the focusing ring, and then the current position of the lens is determined. However, only at the position of the optical coupling can the position data be read, and the position of the lens cannot be obtained in real time.
[0037] In the embodiment, the optical coupling is not needed, and the lens body 112 does not need to go to the optical coupling. By driving the lens to the magnetic signal B of the magnetic inductor 140, the focusing process can be completed, and the time required for the focusing process is accelerated. In the embodiment, a single magnetic element 130 is arranged to realize that the magnetic inductor 140 can obtain the real-time position of the lens body 112 by sensing the magnetic signal of the single magnetic element 130, which simplifies the operation complexity, reduces the volume of the magnetic element 130, and compresses the design cost.
[0038] In some embodiments, one of the magnetic piece 130 and the magnetic inductor 140 is fixedly arranged relative to the focusing piece 120, and the other of the magnetic piece 130 and the magnetic inductor 140 is fixedly arranged relative to the focusing lens barrel 111. That is, when the magnetic piece 130 is fixedly arranged relative to the focusing piece 120 and the magnetic inductor 140 is fixedly arranged relative to the focusing lens barrel 111, the magnetic piece 130 and the focusing piece 120 can be directly connected or indirectly connected, and the magnetic inductor 140 and the focusing lens barrel 111 can be directly connected or indirectly connected. When the magnetic piece 130 is fixedly arranged relative to the focusing lens barrel 111 and the magnetic inductor 140 is fixedly arranged relative to the focusing piece 120, the magnetic piece 130 and the focusing lens barrel 111 can be directly connected or indirectly connected, and the magnetic inductor 140 and the focusing piece 120 can be directly connected or indirectly connected.
[0039] Generally, the movement amplitude of the focusing piece 120 relative to the focusing lens barrel 111 is relatively large compared to the linear movement amplitude of the lens body 112, so as to reduce the sensitivity requirement of the magnetic inductor 140, the precision requirement of the lens component, and the precision requirement of the motor. Moreover, since the movement amplitude of the magnetic piece 130 relative to the magnetic inductor 140 is relatively large, the magnetic inductor 140 can more accurately detect the magnetic field change of the magnetic piece 130, so as to improve the accuracy of focusing.
[0040] In some embodiments, one of the magnetic piece 130 and the magnetic inductor 140 is fixedly arranged relative to the lens body 112, and the other of the magnetic piece 130 and the magnetic inductor 140 is fixedly arranged relative to the focusing lens barrel 111. That is, when the magnetic piece 130 is fixedly arranged relative to the lens body 112 and the magnetic inductor 140 is fixedly arranged relative to the focusing lens barrel 111, the magnetic piece 130 and the lens body 112 can be directly connected or indirectly connected, and the magnetic inductor 140 and the focusing lens barrel 111 can be directly connected or indirectly connected. When the magnetic piece 130 is fixedly arranged relative to the focusing lens barrel 111 and the magnetic inductor 140 is fixedly arranged relative to the lens body 112, the magnetic piece 130 and the focusing lens barrel 111 can be directly connected or indirectly connected, and the magnetic inductor 140 and the lens body 112 can be directly connected or indirectly connected.
[0041] As Figure 1 and Figure 2As shown, in some embodiments, one of the magnetic component 130 and the magnetic sensor 140 is disposed on the focusing component 120, and the other of the magnetic component 130 and the magnetic sensor 140 is disposed on the focusing lens barrel 111. When the focusing component 120 rotates, the magnetic component 130 rotates relative to the magnetic sensor 140 around the optical axis AA. That is, the magnetic component 130 is disposed on the focusing component 120, and the magnetic sensor 140 is disposed on the focusing lens barrel 111, or the magnetic sensor 140 is disposed on the focusing component 120, and the magnetic component 130 is disposed on the focusing lens barrel 111. Exemplarily, the magnetic component 130 can be fixed to the focusing component 120 by means of adhesive, threaded connection, snap-fit, or pressing, and the magnetic sensor 140 can be fixed to the focusing lens barrel 111 by means of adhesive, threaded connection, snap-fit, or pressing.
[0042] The magnetic sensor 140 obtains the rotation distance of the lens body 112 in real time through the magnetic field change of the magnetic component 130, so as to quickly and accurately obtain the real-time position of the component to be focused 120.
[0043] Compared to the transmission component 180, the focusing component 120 and the focusing lens barrel 111 are relatively large, thus providing ample space for the magnetic component 130 and the magnetic sensor 140, thereby reducing the layout difficulty of the magnetic component 130 and the magnetic sensor 140.
[0044] like Figure 3 and Figure 4 As shown, in some embodiments, one of the magnetic component 130 and the magnetic sensor 140 is disposed on the lens body 112, and the other of the magnetic component 130 and the magnetic sensor 140 is disposed on the focusing lens barrel 111. When the focusing component 120 rotates, the magnetic component 130 moves relative to the magnetic sensor 140 along the optical axis AA. That is, the magnetic component 130 is disposed on the lens body 112, and the magnetic sensor 140 is disposed on the focusing lens barrel 111, or the magnetic sensor 140 is disposed on the lens body 112, and the magnetic component 130 is disposed on the focusing lens barrel 111. Exemplarily, the magnetic component 130 can be fixed to the lens body 112 by means of adhesive, threaded connection, snap-fit, crimping, etc., and the magnetic sensor 140 can be fixed to the focusing lens barrel 111 by means of adhesive, threaded connection, snap-fit, crimping, etc.
[0045] Compared to the transmission component 180, the lens body 112 and the focusing lens barrel 111 are relatively large, thus providing ample space for the magnetic component 130 and the magnetic sensor 140, thereby reducing the layout difficulty of the magnetic component 130 and the magnetic sensor 140.
[0046] The magnetic sensor 140 acquires the linear movement distance of the lens body 112 in real time through the magnetic field change of the magnetic member 130, so as to quickly and accurately obtain the real-time position of the focusing member 120. Compared with the rotation amplitude of the focusing member 120, the linear movement amplitude of the lens body 112 is usually smaller, so that the detection range of the magnetic sensor 140 is reduced, and the detection speed is improved. In addition, the surface area of the lens body 112 and the focusing lens barrel 111 are relatively large, and there is enough space for the magnetic member 130 and the magnetic sensor 140, so that the setting position of the magnetic member 130 and the magnetic sensor 140 is relatively flexible.
[0047] As shown in Figure 4 some embodiments, the outer peripheral wall of the lens body 112 is provided with a containing groove, and the magnetic member 130 is arranged in the containing groove, so as to facilitate assembly, and improve the contact area between the magnetic member 130 and the lens body 112, thereby improving the connection reliability and stability between the magnetic member 130 and the lens body 112.
[0048] Optionally, the magnetic member 130 is arranged inside the containing groove, so as to avoid the magnetic member 130 protruding from the lens body 112 and colliding with other components such as the focusing lens barrel 111.
[0049] Optionally, the magnetic member 130 protrudes from the lens body 112, so that the magnetic field of the magnetic member 130 is not shielded as much as possible, which is conducive to the detection of the magnetic signal of the magnetic member 130 by the magnetic sensor 140.
[0050] As shown in Figure 4 some embodiments, the magnetic member 130 is arranged at the end of the end of the lens body 112 protruding from the focusing lens barrel 111, so that the influence on the extension and retraction of the lens body 112 is smaller, and the magnetic member 130 is not easy to collide with the focusing lens barrel 111 when the lens body 112 extends and retracts.
[0051] In some embodiments, the magnetic member 130 and the magnetic sensor 140 are arranged at intervals on the reference axis, and the reference axis is perpendicular to and intersects with the optical axis AA, so as to avoid interference between the magnetic member 130 and the magnetic sensor 140. Moreover, whether the magnetic member 130 and the magnetic sensor 140 are relatively rotated or relatively moved, the distance change between the two is relatively linear, so that the magnetic signal sensed by the magnetic sensor 140 is relatively more linear.
[0052] In some embodiments, the magnetic piece 130 is arranged on the focusing piece 120 or the lens body 112, and the magnetic sensor 140 is arranged on the focusing lens barrel 111. Generally, the volume of the magnetic sensor 140 is greater than that of the magnetic piece 130, and the magnetic piece 130 is arranged on the movable focusing piece 120 or the lens body 112, and the influence of the magnetic piece 130 on the focusing piece 120 or the lens body 112 is small. Moreover, the magnetic sensor 140 needs to be connected with a wire, and therefore the magnetic sensor 140 is arranged on the fixed focusing lens barrel 111, which is beneficial to the arrangement of the wire.
[0053] As shown in FIG. 1, in some embodiments, the focusing device 100 further comprises a distance sensor 160, a driving piece 150 and a control module 170. Figure 5
[0054] The distance sensor 160 is used for measuring the projection distance of the focusing lens 110, that is, the distance d from the focusing lens barrel 111 to the projection surface. The distance sensor 160 can exemplarily be a Time of Flight (TOF) camera or the like.
[0055] The driving piece 150 is in transmission connection with the focusing piece 120 and is used for driving the focusing piece 120 to rotate. The driving piece 150 can exemplarily be a motor, which can drive the focusing piece 120 to rotate through gear transmission or through other existing modes such as a belt pulley.
[0056] The control module 170 is in electrical connection with the driving piece 150, the distance sensor 160 and the magnetic sensor 140. The control module 170 can drive the driving piece 150 to rotate forward, reverse or stop, and the control module 170 can also acquire the distance value measured by the distance sensor 160 and the magnetic field sensed by the magnetic sensor 140.
[0057] The control module 170 outputs a corresponding target magnetic signal according to the projection distance, and controls the driving piece 150 to rotate, so that the magnetic signal detected by the magnetic sensor 140 is the target magnetic signal. By setting the control module 170 and the driving piece 150, automatic focusing can be realized.
[0058] Since the motion state of the lens body 112 can be monitored in real time by the magnetic sensor 140, there is no deviation of the focusing position, thereby avoiding the error caused by the rotation of the driving motor or the gear transmission cooperation in the optical coupling focusing scheme of the prior art, and the focusing precision is high.
[0059] In some embodiments, the magnetic member 130 includes, but is not limited to, at least one of a magnet, a magnetic alloy element. The magnetic sensor 140 includes, but is not limited to, one or more of a linear tunneling magnetoresistance sensor, a linear Hall sensor, an anisotropic magnetoresistance sensor, and a giant magnetoresistance sensor. It can be understood that the above-mentioned sensors can be matched with the magnetic member 130 to achieve a better sensing effect, which is conducive to accurate focusing. Among them, the magnetic sensor 140 is preferably a linear tunneling magnetoresistance sensor and a linear Hall sensor. The linear tunneling magnetoresistance sensor and the linear Hall sensor both map the linear distance change of the magnetic member 130 relative to the sensor through the change of the magnetic flux density.
[0060] The second aspect of the embodiments of the present application provides a projection device, the projection device comprising the focusing device 100 and an optical assembly, the lens body 112 is arranged on the light emitting side of the optical assembly. The optical assembly can exemplarily include a light source, an imaging component, etc. The type of light source can be LED, laser, bulb, etc., and the type of imaging component can be DLP (Digital Light Processing), 3LCD (three-piece liquid crystal display technology), LCoS (Liquid Crystal On Silicon), etc.
[0061] The above only describes the preferred embodiments of the present application, and does not limit the patent scope of the present application, and any equivalent structural transformation made by using the content of the present application specification and drawings, or directly / indirectly applied in other related technical fields is included in the patent protection scope of the present application.
Claims
1. A focusing device, characterized in that, include: A focusing lens includes a focusing lens barrel and a lens body, wherein the lens body has an optical axis and is movably disposed on the focusing lens barrel along the extension direction of the optical axis. A focusing component is rotatably disposed on the focusing lens barrel around the optical axis and is in transmission cooperation with the lens body. When the focusing component rotates, it can drive the lens body to move along the extension direction of the optical axis, and the lens body does not rotate relative to the focusing lens barrel. Magnetic components; as well as A magnetic sensor is used to detect the magnetic signal of the magnetic component; In this configuration, one of the magnetic component and the magnetic sensor is fixedly disposed relative to the focusing component, and the other of the magnetic component and the magnetic sensor is fixedly disposed relative to the focusing lens barrel.
2. The focusing device according to claim 1, characterized in that, One of the magnetic element and the magnetic sensor is disposed on the focusing element, and the other of the magnetic element and the magnetic sensor is disposed on the focusing lens barrel. When the focusing element rotates, the magnetic element rotates relative to the magnetic sensor around the optical axis.
3. A focusing device, characterized in that, include: A focusing lens includes a focusing lens barrel and a lens body, wherein the lens body has an optical axis and is movably disposed on the focusing lens barrel along the extension direction of the optical axis. A focusing component is rotatably disposed on the focusing lens barrel around the optical axis and is in transmission cooperation with the lens body. When the focusing component rotates, it can drive the lens body to move along the extension direction of the optical axis, and the lens body does not rotate relative to the focusing lens barrel. Magnetic components; as well as A magnetic sensor is used to detect the magnetic signal of the magnetic component; In this configuration, one of the magnetic component and the magnetic sensor is fixedly disposed relative to the lens body, and the other of the magnetic component and the magnetic sensor is fixedly disposed relative to the focusing lens barrel.
4. The focusing device according to claim 3, characterized in that, One of the magnetic component and the magnetic sensor is disposed on the lens body, and the other of the magnetic component and the magnetic sensor is disposed on the focusing lens barrel. When the focusing component rotates, the magnetic component moves relative to the magnetic sensor along the optical axis.
5. The focusing device according to claim 3, characterized in that, The magnetic component is disposed on the lens body, and the magnetic sensor is disposed on the focusing lens barrel; The outer peripheral wall of the lens body is provided with a receiving groove, and the magnetic component is disposed in the receiving groove; or The magnetic component is located at the end of the lens body that extends out of the focusing barrel.
6. The focusing device according to any one of claims 1-5, characterized in that, The magnetic component and the magnetic sensor are spaced apart on a reference axis, which is perpendicular to and intersects the optical axis.
7. The focusing device according to any one of claims 1-4, characterized in that, The magnetic sensor is disposed in the focusing lens barrel.
8. The focusing device according to any one of claims 1-5, characterized in that, The focusing component is provided with a spiral groove, the axis of which coincides with the optical axis. The focusing device also includes a transmission component, which is connected to the lens body and slidably disposed in the spiral groove.
9. The focusing device according to any one of claims 1-5, characterized in that, The focusing device further includes: A distance sensor is used to measure the projection distance of the focusing lens; A driving component, which is connected to the focusing component in a transmission manner, is used to drive the focusing component to rotate; The control module is electrically connected to the drive unit, the distance sensor, and the magnetic sensor; The control module outputs a corresponding target magnetic signal based on the projection distance and controls the drive component to rotate so that the magnetic signal detected by the magnetic sensor is the target magnetic signal.
10. A projection device, characterized in that, include: The focusing device as described in any one of claims 1-9; and An optical component, wherein the lens body is disposed on the light-emitting side of the optical component.