A flexible variable focus lens based on low voltage HASEL actuators

Abstract

The utility model belongs to the technical field of flexible drive and optical device, concretely relates to a flexible zoom lens based on low voltage HASEL actuator, and the device includes: top limit frame, VHB adhesive ring, transparent PVC gel film, dielectric liquid, annular cathode, annular anode, liquid injection frame, flow guide frame, rigid support frame and transparent glass. The low voltage HASEL actuator is composed of transparent PVC gel film, annular cathode, annular anode, dielectric liquid and rigid support frame, and the flow guide frame guides the flow of dielectric liquid, makes the transparent PVC gel film of lens aperture area deformation, realizes focal length adjustment. The application has the advantages of simple structure, large focal length change range, short response time, high light transmittance, low power consumption, small size and the like, and is suitable for miniature robots, wearable devices and intelligent optical systems.

Description

Technical Field

[0001] This utility model belongs to the field of flexible drive and optical device technology, specifically relating to a flexible variable focus lens based on a low-voltage HASEL actuator. Background Technology

[0002] In today's optical field, there are various lens technologies used for imaging and focusing, but all of them have some pain points that urgently need to be addressed. Traditional zoom lenses are mainly divided into two categories. One type is a lens system that relies on precision mechanical transmission components to change the distance between lenses to achieve zooming. Its complex internal gears, threads, and other mechanical structures occupy a large space, making it difficult to reduce the overall size. This makes it difficult to adapt to modern miniaturized optical devices with extremely high space utilization requirements, such as thin and light smartphone camera modules and miniature endoscopes. In addition, the mechanical components have large motion inertia, resulting in slow transmission response and limited zooming speed. At the same time, mechanical friction also brings additional energy consumption, and the cumulative power consumption under long-term frequent zooming operations cannot be ignored. The other type is based on piezoelectric... Zoom lenses driven by smart materials such as dielectric elastomers or dielectric elastomers are available. While dielectric elastomer (DE) lenses possess certain flexibility, their actuation requires voltages as high as kilovolts. This not only places extremely high demands on the power supply system, increasing the size and cost of the device, but also poses a risk of breakdown and significant safety hazards. Piezoelectric driven lenses, although having a faster response speed, have a relatively narrow zoom range, making it difficult to meet the needs of some complex applications requiring a wide range of focal length adjustment. Furthermore, the inherent rigidity of piezoelectric materials limits their application potential in flexible optical systems such as wearable optical devices and flexible robot vision systems.

[0003] Liquid zoom lenses, as an emerging optical zoom technology, have shown great potential in the field of miniaturized optical devices due to their unique liquid optical properties. Theoretically, their zooming method, which achieves zooming by changing the shape of a transparent liquid, can break free from the constraints of traditional mechanical structures, resulting in relatively small size and fast zooming speed. However, existing liquid lens technology still faces many challenges. On the one hand, many liquid lenses rely on complex fluid control systems to adjust the liquid shape. These systems often include multiple micro-pumps, valves, pipes, and other components, increasing system complexity and manufacturing costs, and making it difficult to further reduce the overall size of the lens. This hinders applications requiring extreme space compression, such as micro-robots and ultra-thin mobile phone cameras. On the other hand, some liquid lenses use high-voltage actuation to change the surface tension of the liquid or the shape of the liquid material. High-voltage actuation also brings problems such as high power consumption, demanding power supply requirements, and safety hazards, making it difficult to widely apply in portable and implantable optical devices that are sensitive to power consumption and require long-term stable operation. Utility Model Content

[0004] This invention provides a flexible variable focus lens based on a low-voltage HASEL actuator to solve the technical problems existing in the prior art.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A flexible variable focus lens based on a low-voltage HASEL actuator includes a transparent PVC gel film. The transparent PVC gel film includes an outer peripheral protrusion and a central protrusion. The upper outer periphery of the transparent PVC gel film is a first frame, and the lower outer periphery of the transparent PVC gel film is a second frame. An annular cathode is provided between the transparent PVC gel film and the first frame, and an annular anode is provided between the transparent PVC gel film and the second frame. The lower end of the second frame is transparent glass. A sealed cavity is formed between the first frame, the transparent PVC gel film, and the transparent glass, and the sealed cavity is filled with a dielectric liquid.

[0007] The upper end of the junction between the outer peripheral protrusion and the central protrusion of the transparent PVC gel film is a top limiting frame, and the lower end of the junction is a flow guiding frame. The top limiting frame and the flow guiding frame are vertically corresponding, and the top limiting frame, the flow guiding frame and the transparent PVC gel film are all bonded and sealed together.

[0008] Part of the annular cathode is located on the inner and upper walls of the first frame, while the remaining part of the annular cathode is located on the upper surface of the raised portion on the outer periphery of the transparent PVC gel film.

[0009] Part of the annular anode is located on the inner and lower walls of the second frame, while the remaining part is located on the upper surface of the second frame at the lower end of the protruding portion on the outer periphery of the transparent PVC gel film.

[0010] A VBH adhesive ring is provided between the transparent PVC gel film and the second frame for bonding and sealing the transparent PVC gel film.

[0011] A sealed space is formed between the transparent PVC gel film, the second frame, and the transparent glass. The inner wall of the sealed cavity is provided with a liquid injection frame, into which dielectric liquid is injected.

[0012] The dielectric liquid is a transparent liquid made of mineral oil and DBA plasticizer mixed in a 1:1 ratio.

[0013] The injection frame is equipped with injection pipes, through which dielectric liquid is injected into the sealed space.

[0014] The transparent PVC gel film is obtained by combining PVC plastic particles and DBA plasticizer in a 1:2 ratio, and the thickness of the transparent PVC gel film is 200μm.

[0015] The annular cathode is a carbon paste motor, and the annular anode is a conductive tape. The coverage area ratio of the annular cathode to the annular anode is 1:1.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] This invention proposes a flexible variable focus lens based on a low-voltage HASEL actuator. A transparent PVC gel film forms a sealed cavity with the first frame, the second frame, and the transparent glass. A top limiting frame and a flow guiding frame are respectively provided at the junction of the outer peripheral protrusion and the central protrusion of the transparent PVC gel film, and both are bonded and sealed. This structural design effectively prevents dielectric fluid leakage, ensuring the stability and reliability of the lens operation. Furthermore, the VBH bonding ring further enhances the bonding and sealing effect between the transparent PVC gel film and the second frame, improving the overall sealing performance and extending the service life of the lens.

[0018] Furthermore, the annular cathode portion is located on the inner and upper walls of the first frame, with the remaining portion located on the upper surface of the raised portion on the outer periphery of the transparent PVC gel film; the annular anode portion is located on the inner and lower walls of the second frame, with the remaining portion located on the upper surface of the second frame at the lower end of the raised portion on the outer periphery of the transparent PVC gel film. This electrode arrangement helps to form a uniform electric field on the raised portion on the outer periphery of the transparent PVC gel film, improves the driving effect of the electric field on the transparent PVC gel film, enhances its adsorption motion efficiency and stability, and thus more accurately controls the zoom effect of the lens.

[0019] Furthermore, the inner wall of the sealed space formed between the transparent PVC gel film, the second frame, and the transparent glass is provided with a liquid injection frame, and the liquid injection frame is provided with a liquid injection pipe. The dielectric liquid can be injected into the sealed space through the liquid injection pipe, which makes the filling of dielectric liquid more convenient and quick, and it is also easy to operate when the dielectric liquid needs to be replaced, ensuring the stability and adjustability of the lens performance.

[0020] Furthermore, the transparent PVC gel film is made by combining PVC plastic particles and DBA plasticizer in a 1:2 ratio, with a thickness of 200μm. This material ratio and thickness design ensure that the transparent PVC gel film has both good flexibility and certain mechanical strength and optical performance, meeting the deformation requirements of the lens during zooming. At the same time, the dielectric liquid is a transparent liquid made by mixing mineral oil and DBA plasticizer in a 1:1 ratio. This material combination ensures the dielectric properties and fluidity of the dielectric liquid, and also has good compatibility with the transparent PVC gel film, which is beneficial to improving the overall performance and response speed of the lens.

[0021] Furthermore, the present invention proposes a working method for a flexible variable focus lens based on a low-voltage HASEL actuator. By energizing the annular cathode and annular anode, the transparent PVC gel film undergoes adsorption motion on the outer peripheral protrusions towards the upper surface of the second frame, squeezing the internal dielectric liquid and causing it to surge upwards. This causes the central protrusion of the transparent PVC gel film to bulge upwards, achieving the zoom function. This working principle based on a low-voltage HASEL actuator can quickly drive the transparent PVC gel film to deform at a lower voltage, reducing energy consumption and improving response speed, enabling more efficient dynamic adjustment of the focal length in practical applications. Attached Figure Description

[0022] Figure 1 A schematic diagram of the structure of a flexible variable focus lens device based on a low-voltage HASEL actuator provided in an embodiment of this application;

[0023] Figure 2 A schematic diagram of liquid zoom in a flexible variable focus lens device based on a low-voltage HASEL actuator provided in an embodiment of this application.

[0024] 1. Top-level confinement frame; 2. First frame; 3. VHB bonding ring; 4. Annular cathode; 5. Transparent PVC gel film; 6. Current guiding frame; 7. Annular anode; 8. Second frame; 9. Injection frame; 10. Dielectric liquid; 11. Transparent glass; 12. Injection channel. Detailed Implementation

[0025] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope of this invention. Therefore, the drawings and description are considered exemplary in nature and not restrictive.

[0026] The embodiments of this utility model will now be described in detail with reference to the accompanying drawings.

[0027] Example 1

[0028] This embodiment proposes a flexible variable focus lens based on a low-voltage HASEL actuator, such as... Figure 1As shown, this application provides a flexible variable focus lens device based on a low-voltage HASEL actuator, comprising: a top limiting frame 1, a first frame 2, a second frame 8, a VHB bonding ring 3, a transparent PVC gel film 5, a dielectric liquid 10, a ring cathode 4, a ring anode 7, a liquid injection frame 9, a flow guiding frame 6, and a transparent glass 11. The dielectric liquid 10 is a transparent liquid composed of mineral oil and DBA plasticizer mixed in a 1:1 ratio. The transparent PVC gel film 5 is obtained by combining PVC plastic particles and DBA plasticizer in a 1:2 ratio, and the thickness of the transparent PVC gel film 5 is 200 μm. The transparent PVC gel film 5 includes a peripheral protrusion and a central protrusion. The upper end of the junction between the peripheral and central protrusions of the transparent PVC gel film 5 is a top limiting frame 1, and the lower end is a flow guiding frame 6. The top limiting frame 1 and the flow guiding frame 6 correspond vertically and form a first rigid support frame. The first frame 2 and the second frame 8 form a second rigid support frame. Both frames are annular rigid frames. The first frame 2 and the second frame 8 form the second rigid support frame for fixing the outer part of the electrode of the transparent PVC gel film 5. The top limiting frame 1 and the flow guiding frame 6 form the first rigid support frame for fixing the inner part of the electrode of the transparent PVC gel film 5. The transparent PVC gel film 5 is located between the two rigid support frames. The upper peripheral end of the transparent PVC gel film 5 is the first frame 2. A VBH adhesive ring 3 is provided between the transparent PVC gel film 5 and the second frame 8 for bonding and sealing the transparent PVC gel film. In this embodiment, the VHB adhesive ring 3 is VHB tape manufactured by 3M, a high-performance double-sided tape. The lower periphery of the transparent PVC gel film 5 forms a second frame 8. An annular cathode 4 is positioned between the transparent PVC gel film 5 and the first frame 2. Part of the annular cathode 4 is located on the inner and upper walls of the first frame 2, while the remaining portion is located on the upper surface of the protruding portion on the outer periphery of the transparent PVC gel film 5. An annular anode 7 is positioned between the transparent PVC gel film 5 and the second frame 8. Part of the annular anode 7 is located on the inner and lower walls of the second frame 8, while the remaining portion is located on the upper surface of the second frame 8 at the lower end of the protruding portion on the outer periphery of the transparent PVC gel film 5. The annular cathode 4 is a carbon paste electrode, and the annular anode 7 is a conductive tape. The coverage area ratio of the annular cathode 4 to the annular anode 7 is 1:1. The lower end of the second frame 8 is a transparent glass 11. A sealed cavity is formed between the first frame 2, the transparent PVC gel film 5, and the transparent glass 11, and this sealed cavity is filled with a dielectric liquid 10.A sealed space is formed between the transparent PVC gel film 5, the second frame 8, and the transparent glass 11. A liquid injection frame 9 is provided on the inner wall of this sealed cavity, located between the second frame 8 and the transparent glass 11, for connecting a liquid injection pipe 12 to inject the dielectric liquid 10. The liquid injection frame 9 has a liquid injection pipe 12, through which the dielectric liquid 10 is injected into the sealed space. Specifically, the first frame 2, the second frame 8, the top limiting frame 1, the flow guiding frame 6, and the liquid injection frame 9 mentioned above are, but are not limited to, rigid acrylic frames, and are properly insulated and sealed.

[0029] In summary, the flexible variable focal length lens based on a low-voltage HASEL actuator described above has advantages such as simple structure, large focal length variation range, short response time, high light transmittance, low power consumption, and small size. It is suitable for use in devices that require rapid zooming while having strict size requirements, such as micro-robots, wearable devices, and intelligent optical systems, and has high research value.

[0030] Based on the aforementioned flexible variable-focus lens using a low-voltage HASEL actuator, this method achieves the zoom function of a liquid lens by utilizing the principle of a transparent PVC gel film adsorbing towards the anode under voltage, thereby altering the shape of the transparent dielectric liquid. The specific implementation method is as follows:

[0031] Before energizing the annular cathode 4 and annular anode 7, dielectric liquid 10 is injected into the sealed space through the injection pipe 12. At this time, both the outer and central protrusions of the transparent PVC gel film 5 are partially raised. Simultaneously, dielectric liquid 10 is injected through the injection frame 9 and the injection pipe 12, ensuring full contact between the dielectric liquid 10 and the transparent PVC gel film 5, while simultaneously sealing and insulating the internal space. By changing the volume of the injected dielectric liquid 10, the initial focal length of the liquid zoom lens is altered. When the annular anode 7 is connected to a positive electric field and the annular cathode 4 is grounded, the electric field forms a circuit through the transparent PVC gel film 5, the dielectric liquid 10, and the annular cathode 4. Utilizing the fact that the transparent PVC gel film 5 can undergo adsorption deformation towards the inner wall anode under the action of the electric field, the electrode portion around the transparent PVC gel film 5 is driven to adsorb towards the inner wall of the second frame 8. That is, the outer peripheral protrusion of the transparent PVC gel film 5 adsorbs towards the upper surface of the second frame 8. The transparent PVC gel film 5 compresses the internal dielectric liquid 10, causing the dielectric liquid 10 to surge upwards, resulting in the upward protrusion of the central protrusion of the transparent PVC gel film 5. This increases the radius of curvature of the central protrusion of the PVC gel film 5. Figure 2 As shown, by continuously changing the electric field strength, the curvature of the central protrusion of the transparent PVC gel film 5 changes continuously with the change in electric field strength, thereby changing the focal length of the liquid zoom lens. This achieves the zoom function of the liquid lens based on different applied electric field strengths.

[0032] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can be appropriately combined to form other embodiments that can be understood by those skilled in the art. The above content is only for illustrating the technical concept of this utility model and should not be used to limit the scope of protection of this utility model. Any modifications made to the technical solutions based on the technical concept proposed by this utility model shall fall within the scope of protection of the claims of this utility model.

Claims

1. A flexible variable focus lens based on a low-voltage HASEL actuator, characterized in that, The transparent PVC gel film (5) includes an outer peripheral protrusion and a central protrusion. The upper outer periphery of the transparent PVC gel film (5) is a first frame (2), and the lower outer periphery of the transparent PVC gel film (5) is a second frame (8). An annular cathode (4) is provided between the transparent PVC gel film (5) and the first frame (2), and an annular anode (7) is provided between the transparent PVC gel film (5) and the second frame (8). The lower end of the second frame (8) is a transparent glass (11). A sealed cavity is formed between the first frame (2), the transparent PVC gel film (5), and the transparent glass (11), and the sealed cavity is filled with a dielectric liquid (10).

2. A flexible variable focus lens based on a low-voltage HASEL actuator according to claim 1, characterized in that, The upper end of the junction between the outer peripheral protrusion and the central protrusion of the transparent PVC gel film (5) is a top limiting frame (1), and the lower end of the junction is a flow guiding frame (6). The top limiting frame (1) and the flow guiding frame (6) correspond to each other vertically, and the top limiting frame (1), the flow guiding frame (6) and the transparent PVC gel film (5) are all bonded and sealed together.

3. A flexible variable focus lens based on a low-voltage HASEL actuator according to claim 1, characterized in that, Part of the annular cathode (4) is located on the inner and upper walls of the first frame (2), and the remaining part of the annular cathode (4) is located on the upper surface of the raised portion of the outer periphery of the transparent PVC gel film (5).

4. A flexible variable focus lens based on a low-voltage HASEL actuator according to claim 1, characterized in that, Part of the annular anode (7) is located on the inner wall and lower wall of the second frame (8), and the remaining part is located on the upper surface of the second frame (8) at the lower end of the outer periphery protrusion of the transparent PVC gel film (5).

5. A flexible variable focus lens based on a low-voltage HASEL actuator according to claim 1, characterized in that, A VBH bonding ring (3) is provided between the transparent PVC gel film (5) and the second frame (8) for bonding and sealing the transparent PVC gel film.

6. A flexible variable focus lens based on a low-voltage HASEL actuator according to claim 1, characterized in that, A sealed space is formed between the transparent PVC gel film (5), the second frame (8) and the transparent glass (11), and the inner wall of the sealed space is provided with a liquid injection frame (9), into which dielectric liquid (10) is injected.

7. A flexible variable focus lens based on a low-voltage HASEL actuator according to claim 6, characterized in that, The liquid injection frame (9) is provided with a liquid injection pipe (12), and the dielectric liquid (10) is injected into the sealed space through the liquid injection pipe (12).

8. A flexible variable focus lens based on a low-voltage HASEL actuator according to claim 1, characterized in that, The annular cathode (4) is a carbon paste motor, and the annular anode (7) is a conductive tape. The coverage area ratio of the annular cathode (4) to the annular anode (7) is 1:1.

Images