CN111751910A - Liquid lens zooming imaging method and system based on dielectric elastomer - Google Patents
Liquid lens zooming imaging method and system based on dielectric elastomer Download PDFInfo
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- CN111751910A CN111751910A CN202010639412.5A CN202010639412A CN111751910A CN 111751910 A CN111751910 A CN 111751910A CN 202010639412 A CN202010639412 A CN 202010639412A CN 111751910 A CN111751910 A CN 111751910A
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Abstract
The invention discloses a liquid zoom imaging method and system based on a dielectric elastomer, and belongs to the field of optical imaging. The invention applies voltage in the electrode area of the plane dielectric elastomer to drive the bottom radius of the flexible hollow round table to change, so that the shape parameters of liquid including liquid height, radius and bow height are changed, and the focal length of the liquid lens is changed. By optimizing system parameters, when the difference of the focal positions of the liquid lenses before and after driving is within the semi-focal depth of the imaging system, the zoom imaging of a single driven liquid lens is realized, and the zoom imaging system has the advantages of simple driving structure, large zoom range, high response speed, small volume, low cost and the like. The zoom imaging function is realized by combining the planar dielectric elastomer and the flexible hollow round table, the flexible hollow round table has no special requirement on the thickness, no dielectric elastic material is needed, only the planar dielectric elastomer uses the dielectric elastic material, and the planar dielectric elastomer is easy to process.
Description
Technical Field
The invention relates to a liquid zoom imaging method and system based on a dielectric elastomer, and belongs to the field of optical imaging.
Background
The zoom imaging system is widely applied to various fields of industry, medical treatment, military, life and the like, and the liquid lens has the advantages of small size, simple structure, high speed, polarization independence, long service life and the like, so people can apply the liquid lens to the zoom imaging system at present. The existing liquid lens zoom imaging method mainly comprises a mode of combining a solid lens and a liquid lens, a plurality of liquid lenses, a single liquid lens of a multi-driving unit and the like. The manner in which solid and liquid lenses are combined is complicated by the fact that multiple solid lenses are typically required, and therefore, the system construction and assembly is complicated. The multiple liquid lenses approach eliminates the solid lens, but requires multiple liquid lenses, which is costly and complicated to control. The single liquid lens approach of the multi-driving unit only needs a single liquid lens, however, since a plurality of driving units including electrowetting, electromagnetic driving, etc. are needed, the driving units are complicated in structure and control. In order to reduce the volume, cost and control complexity of the zoom system, it is desirable to realize zoom imaging by a single driving unit on the basis of a single liquid lens. The patent "a single-drive liquid zoom lens and a manufacturing method thereof, and a zoom imaging method" (application number CN202010090689.7) discloses an imaging method for realizing zooming by using a single-drive liquid zoom lens, which also adopts a dielectric elastomer as a drive unit, but the method is to design a dielectric elastomer material into a truncated cone-shaped film structure, and since the thickness of the truncated cone-shaped electricity-saving elastomer film is only about tens of microns to hundreds of microns, a higher requirement is provided for the current processing technology, and therefore, in order to reduce the processing difficulty, an easy-to-process liquid lens zoom imaging method based on the dielectric elastomer is urgently needed.
Disclosure of Invention
The invention discloses a liquid zoom imaging method and a liquid zoom imaging system based on a dielectric elastomer, and the technical problems to be solved are as follows: the advantages of large deformation, large driving force, high response speed and the like of the dielectric elastomer are utilized, the single dielectric elastomer is adopted to realize large-range and quick zooming imaging, and the method has the advantages of small processing difficulty, simple structure, easy control and the like.
The purpose of the invention is realized by the following technical scheme.
The invention discloses a liquid zoom imaging method based on a dielectric elastomer. The bottom radius of the flexible hollow round table is driven to change by driving the plane dielectric elastomer to deform, liquid is injected into the flexible hollow round table, flexible electrodes are coated on peripheral regions of the upper surface and the lower surface of the plane dielectric elastomer, when the two flexible electrodes have voltage difference, the area of the region, coated with the electrodes, of the plane dielectric elastomer is increased, the bottom of the flexible hollow round table is driven to shrink, the radius of the bottom is reduced, and then the shape of the liquid in the flexible hollow round table is changed, wherein the shape comprises the height of the liquid, the radius and the height of a bow, so that the focal length of the liquid lens is changed. When the focal length of the liquid lens is changed and the difference of the focal positions of the liquid lens before and after driving is within the half focal depth of the imaging system, the imaging system can change the imaging size more clearly, the zoom imaging function of a single liquid lens driven by a single lens is realized, and the liquid lens zoom lens has the advantages of large zoom range, high response speed, small volume, low cost and simple driving. The zoom imaging function is realized by combining the plane dielectric elastomer and the flexible hollow round table, the flexible hollow round table has no special requirement on the thickness, the dielectric elastic material is not needed, only the plane dielectric elasticity is used, and the plane dielectric elastomer is easy to process, so that the combination of the plane dielectric elastomer and the flexible hollow round table is easy to process.
The invention discloses a liquid zoom imaging system based on a dielectric elastomer, which is used for realizing the liquid zoom imaging method based on the dielectric elastomer. The planar dielectric elastomer is a planar dielectric elastomer easy to process, the upper fixing plate and the lower fixing plate are used for fixing the planar dielectric elastomer, the upper surface and the lower surface of the peripheral area of the planar dielectric elastomer are uniformly coated with the upper flexible electrode and the lower flexible electrode, the radius of the central area is the radius of the bottom of the flexible hollow circular truncated cone, the upper flexible electrode is electrically connected to a power supply, and the lower flexible electrode is electrically connected to the ground end. The bottom of the flexible hollow round table is adhered to the central area of the plane dielectric elastomer. The hollow cylinder is adhered to the upper fixing plate. Liquid is injected into the flexible hollow round table, and the top of the flexible hollow round table is adhered to the fixed transparent flat plate.
To obtain a large zoom ratio and zoom speed, the planar dielectric elastomer material is preferably pre-stretched VHB4910, VHB4905 or PDMS.
In order to obtain a large zoom ratio, the flexible hollow truncated cone is preferably made of PDMS or a rubber-like material.
In order to reduce the processing difficulty, the flexible hollow round table is preferably processed by a 3D printing or twice injection molding process.
In order to reduce the processing difficulty, the bottom of the flexible hollow round table is preferably adhered to the central area of the planar dielectric elastomer through a plasma oxidation process.
In order to obtain a large zoom ratio, the liquid material is preferably a mixed solution of glycerin and water.
In order to reduce the processing difficulty, the upper flexible electrode and the lower flexible electrode are preferably made of carbon paste, carbon nanotubes or carbon powder.
In order to facilitate the adhesion with the VHB4910, VHB4905 or PDMS, the upper and lower fixing plates are preferably made of an acrylic material.
The invention discloses a working method of a liquid zoom imaging system based on a dielectric elastomer, which comprises the following steps:
the method comprises the following steps: when the switch of the power supply is switched off, the planar dielectric elastomer is not driven because the upper flexible electrode and the lower flexible electrode have no voltage difference, and the radius of the bottom of the flexible hollow circular truncated cone is a1The radius of the top of the flexible hollow round table is bThe height is h. The flexible hollow round table is filled with liquid, and the height of the liquid surface before the driving of the plane dielectric elastomer is h0Radius r0Bow height s0The volume V of the liquid at this time is expressed as:
liquid lens focal length f before planar dielectric elastomer drive0Expressed as:
after the incident parallel light rays are acted by the liquid surface before being driven by the dielectric elastomer, the converged light rays before being driven are focused on the focal position before being driven.
Step two: when the power supply is switched on and off, the planar dielectric elastomer is driven due to the voltage difference between the upper flexible electrode and the lower flexible electrode, the area of the region of the planar dielectric elastomer coated with the electrodes is increased, the bottom of the flexible hollow circular truncated cone is driven to contract, and the radius of the flexible hollow circular truncated cone is changed into a0. Because the top of the flexible hollow round table is fixed by the fixed transparent flat plate, the cone angle of the flexible hollow round table changes, the shape of the liquid surface after driving changes, and the liquid height changes to h1The radius of the liquid becomes r1Liquid bow height changed to s1. Because the liquid volume is unchanged and the contact angle of the liquid-flexible hollow round table is unchanged, and simultaneously, according to the triangular geometrical relationship, when the bottom of the flexible hollow round table is changed into a0And (3) calculating three parameters of the height of the liquid, the radius of the liquid and the height of the liquid arch after driving according to the formula (3).
Wherein theta is a contact angle between the liquid and the flexible hollow circular truncated cone. The height, liquid radius and liquid bow height of the liquid are changed after the driving, so that incident parallel light rays are driven by the dielectric elastomerAfter the action of the liquid surface, the driven convergent light is focused on the driven focal position. The focal length after driving will also change, and the changed focal length f of the liquid lens1Comprises the following steps:
wherein: f. of1Is the changed focal length of the liquid lens.
In order to enable the liquid lens to realize zoom imaging, the difference between the focal positions of the liquid lens before and after driving should be within the half-focal depth of the imaging system, i.e.
Where is the depth of focus of the imaging system. After the formula (5) is satisfied, the system can be ensured to image clearly, and the zoom ratio of the liquid lens is as follows:
the liquid lens zooming with different zoom ratios is obtained by optimizing the structural parameters of the flexible hollow round table and the initial shape of liquid, so that the single liquid lens zooming function can be realized by single driving by applying voltage on the dielectric elastomer, the flexible hollow round table has no special requirement on the thickness, and the flexible hollow round table is obtained by 3D printing or twice injection molding process, and has the advantage of easy processing.
Step three: the liquid lenses should have different focal lengths according to different zoom application requirements. When the liquid lens has a long focal length and a short focal length, in order to reduce the length of the zoom imaging system, different camera structural modes are required to be adopted to cooperate with the liquid lens to complete zoom imaging. Under different focal lengths of the liquid lenses, the imaging mode of the liquid zoom imaging system based on the dielectric elastomer comprises a first mode and a second mode:
the first method is as follows: when the liquid lens in the flexible hollow circular truncated cone has a long focal length, a camera structure comprising a concave lens, a convex lens and an image sensor is adopted, wherein the image space focal point of the liquid lens is superposed with the image space focal point of the concave lens. Incident parallel light rays emitted from an infinite target are converged by a liquid lens in the flexible hollow circular truncated cone, then are changed into parallel light rays under the action of a concave lens, and finally are focused by a convex lens to be imaged on an image sensor.
The second method comprises the following steps: when the liquid lens in the flexible hollow circular truncated cone has a short focal length, a camera structure comprising a convex lens, a convex lens and an image sensor is adopted, wherein the image space focal point of the liquid lens is superposed with the object space focal point of the concave lens. Incident parallel light rays emitted from an infinite target are converged by a liquid lens in the flexible hollow circular truncated cone, then are changed into parallel light rays under the action of a convex lens, and finally are focused by the convex lens to be imaged on an image sensor.
Has the advantages that:
1. according to the liquid zoom imaging method and system based on the dielectric elastomer, voltage is applied to the electrode area of the planar dielectric elastomer to drive the bottom radius of the flexible hollow circular truncated cone to change, so that the shape parameters of liquid including the height, the radius and the height of bow are changed, and the focal length of a liquid lens is changed. By optimizing system parameters, when the difference of the focal positions of the liquid lenses before and after driving is within the semi-focal depth of the imaging system, the zoom imaging of a single driven liquid lens is realized, and the zoom imaging system has the advantages of simple driving structure, large zoom range, high response speed, small volume, low cost and the like.
2. The invention discloses a liquid zoom imaging method and system based on a dielectric elastomer, wherein a plane dielectric elastomer is attached to the bottom surface of a flexible hollow round table, the radius of the bottom of the flexible hollow round table is driven to change by driving the plane dielectric elastomer to deform, namely, the zoom imaging function is realized by combining the plane dielectric elastomer and the flexible hollow round table, the flexible hollow round table does not need to use a dielectric elastic material, only the plane dielectric elastomer uses the dielectric elastic material, and the plane shape enables the plane dielectric elastomer to be easily processed, so that the combination of the plane dielectric elastomer and the flexible hollow round table is easy to process.
3. The liquid zoom imaging method and system based on the dielectric elastomer, disclosed by the invention, have no special requirements on the thickness of the flexible hollow round table, avoid the difficulty in processing the round table-shaped electricity-saving elastomer film with the thickness of about dozens of microns to hundreds of microns, can be obtained by adopting mature processes such as 3D printing or twice injection molding and the like, and have the advantage of low processing difficulty.
Drawings
Fig. 1 is an exploded view of a liquid zoom imaging system based on dielectric elastomer.
FIG. 2 is a cross-sectional view of a dielectric elastomer based liquid zoom imaging system according to the present disclosure.
Fig. 3 is a schematic diagram of the operation of a liquid zoom imaging system based on a dielectric elastomer according to the disclosure.
Fig. 4 is an imaging schematic diagram (the focal length of the liquid lens is longer) of a liquid zoom imaging system based on a dielectric elastomer disclosed by the invention.
Fig. 5 is an imaging schematic diagram (the focal length of the liquid lens is shorter) of a liquid zoom imaging system based on a dielectric elastomer disclosed by the invention.
Wherein: 1-fixed transparent flat plate, 2-flexible hollow round table, 3-liquid, 4-hollow cylinder, 5-upper fixed plate, 6-dielectric elastomer, 7-upper flexible electrode, 8-lower flexible electrode, 9-lower fixed plate, 10-power supply, 11-bottom of flexible hollow round table, 12-top of flexible hollow round table, 13-height of flexible hollow round table, 14-incident parallel light, 15-liquid surface before driving, 16-liquid surface after driving, 17-converged light before driving, 18-converged light after driving, 19-focus before driving, 20-focus after driving, 21-infinite object, 22-concave lens, 23-convex lens, 24-image sensor, 25-camera, etc, 26-convex lens.
It should be understood that the above-described figures are merely schematic and are not drawn to scale.
Detailed Description
The following describes embodiments of the present invention with reference to the drawings.
As shown in fig. 1 and fig. 2, the liquid zoom imaging system based on a dielectric elastomer disclosed in this embodiment includes a fixed transparent flat plate 1, a flexible hollow circular truncated cone 2, a liquid 3, a hollow cylinder 4, an upper fixture 5, a planar dielectric elastomer 6, an upper flexible electrode 7, a lower flexible electrode 8, a lower fixed plate 9, and a power supply 10. The upper fixing plate 5 and the lower fixing plate 9 are used for fixing the planar dielectric elastomer 6, the upper surface and the lower surface of the peripheral area of the planar dielectric elastomer 6 are uniformly coated with an upper flexible electrode 7 and a lower flexible electrode 8, the radius of the central area is the radius of the bottom of the flexible hollow circular truncated cone 2, the upper flexible electrode is electrically connected to a power supply 10, and the lower flexible electrode 8 is electrically connected to the ground end. The bottom of the flexible hollow round table 2 is adhered to the central area of the plane dielectric elastomer 6 through a plasma oxidation process. The hollow cylinder 4 is glued to the upper fixing plate 5 by means of an adhesive glue. Liquid 3 with a certain volume is injected into the flexible hollow round table 2, and the top of the flexible hollow round table 2 is adhered to the fixed transparent flat plate 1 through adhesive glue.
The planar dielectric elastomer 6 material is pre-stretched VHB 4910.
The flexible hollow round table 2 is made of PDMS.
The flexible hollow round table 2 is obtained through 3D printing.
The bottom of the flexible hollow round table 2 is adhered to the central area of the plane dielectric elastomer 6 through a plasma oxidation process.
The liquid 3 material is a mixed solution of glycerol and water.
The upper flexible electrode 7 and the lower flexible electrode 8 are made of carbon paste.
For the convenience of the VHB4910, the material of the upper and lower fixing plates 5 and 9 is preferably acrylic material.
As shown in fig. 3, the working method of the liquid zoom imaging method based on the dielectric elastomer disclosed in this embodiment includes the following steps:
the method comprises the following steps: when the switch of the power supply 10 is turned off, the planar dielectric elastomer 6 is not driven because there is no voltage difference between the upper flexible electrode 7 and the lower flexible electrode 8, and the radius of the bottom 11 of the flexible hollow circular truncated cone is a1The radius of the top 12 of the flexible hollow circular truncated cone is b, and the height 13 of the flexible hollow circular truncated cone is h. The liquid 3 is injected into the flexible hollow round table 2, and the height of the liquid surface 15 before the driving of the plane dielectric elastomer 6 is h0Radius r0Bow height s0The volume V of the liquid 3 at this time is expressed as:
liquid lens focal length f before driving of plane dielectric elastomer 60Expressed as:
after the incident parallel light rays pass through the liquid surface 15 before the driving of the dielectric elastomer, the convergent light rays 17 before the driving are focused on the position of the focal point 19 before the driving.
Step two: when the switch of the power supply 10 is closed, the planar dielectric elastomer 6 is driven due to the voltage difference between the upper flexible electrode 7 and the lower flexible electrode 8, the area of the electrode-coated region of the planar dielectric elastomer 6 is increased, the bottom 11 of the flexible hollow circular truncated cone is driven to contract, and the radius of the flexible hollow circular truncated cone is changed into a0. Since the top 12 of the flexible hollow circular truncated cone is fixed by the fixed transparent plate, the cone angle of the flexible hollow circular truncated cone 2 will change, resulting in the shape of the driven liquid surface 16 changing, its liquid height becoming h1The radius of the liquid becomes r1Liquid bow height changed to s1. Because the volume of the liquid 3 is unchanged and the contact angle of the liquid 3 and the flexible hollow round table 2 is unchanged, and simultaneously, according to the triangular geometrical relationship, when the bottom 11 of the flexible hollow round table is changed into a0And (3) calculating three parameters of the height of the liquid, the radius of the liquid and the height of the liquid arch after driving according to the formula (3).
Wherein theta is a contact angle between the liquid 3 and the flexible hollow round table 2. Due to the liquid after drivingThe height, liquid radius and liquid arch height of the light source 3 are changed, and after the incident parallel light rays are acted by the liquid surface 16 driven by the dielectric elastomer, the driven convergent light rays 18 are focused on the position of the driven focal point 20. The focal length after driving will also change, and the changed focal length f of the liquid lens1Comprises the following steps:
wherein: f. of1Is the changed focal length of the liquid lens.
In order to enable the liquid lens to realize zoom imaging, the difference between the focal positions of the liquid lens before and after driving should be within the half-focal depth of the imaging system, i.e.
Where is the depth of focus of the imaging system. After the formula (5) is satisfied, the system can be ensured to image clearly, and the zoom ratio of the liquid lens is as follows:
the liquid lens zooming with different zoom ratios is obtained by optimizing the structural parameters of the flexible hollow round table 2 and the initial shape of the liquid 3, so that the single liquid lens zooming function can be realized by single driving by applying voltage on the dielectric elastomer, the flexible hollow round table 2 has no special requirement on the thickness, and the flexible hollow round table is obtained by 3D printing or twice injection molding process, and has the advantage of easy processing.
Step three: the liquid lens 3 should have different focal lengths according to different zoom application requirements. When the liquid lens 3 has a long focal length and a short focal length, in order to reduce the length of the zoom imaging system, different camera structure modes are required to be adopted to cooperate with the liquid lens 3 to complete zoom imaging. At different focal lengths of the liquid lens 3, the imaging modes of the liquid zoom imaging system based on the dielectric elastomer include a mode one and a mode two:
as shown in fig. 4, the first method: when the liquid lens 3 in the flexible hollow circular truncated cone 2 has a long focal length, a camera 25 structure including a concave lens 22, a convex lens 23 and an image sensor 24 is adopted, wherein the image side focal point of the liquid lens 3 and the image side focal point of the concave lens 22 coincide. The incident parallel light 14 emitted from the infinite target 21 is converged by the liquid lens 3 in the flexible hollow circular truncated cone 2, then is changed into parallel light by the action of the concave lens 22, and finally is focused by the convex lens 23 to be imaged on the image sensor 24.
As shown in fig. 5, the second method: when the liquid lens 3 in the flexible hollow circular truncated cone 2 has a short focal length, a camera 25 structure including a convex lens 26, a convex lens 23, and an image sensor 24 is adopted, wherein the image side focal point of the liquid lens 3 and the object side focal point of the concave lens 22 coincide. The incident parallel light 14 emitted from the infinite target 21 is converged by the liquid lens 3 in the flexible hollow circular truncated cone 2, then is changed into parallel light by the action of the convex lens 26, and finally is focused by the convex lens 23 to be imaged on the image sensor 24.
In summary, compared with the conventional method, in the present embodiment, a single liquid lens with a single driving unit is adopted to realize zoom imaging, and the zoom imaging function is realized by combining the planar dielectric elastomer and the flexible hollow circular truncated cone, the flexible hollow circular truncated cone does not need to use a dielectric elastic material, only the planar dielectric elastomer uses the dielectric elastic material, and the planar shape makes the planar dielectric elastomer easy to process, so that the combination of the planar dielectric elastomer and the flexible hollow circular truncated cone is easy to process; in addition, the embodiment has no special requirements on the thickness and the material of the flexible hollow round table, avoids the process problem of processing the round table-shaped film with the thickness of about dozens of microns to hundreds of microns, eliminates the limitation of needing a dielectric elastomer material, and has the advantages of easy processing, large zooming range, high response speed, small volume, low cost and simple driving.
The above detailed description is intended to illustrate the objects, aspects and advantages of the present invention, and it should be understood that the above detailed description is only exemplary of the present invention and is not intended to limit the scope of the present invention, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present invention should be included in the scope of the present invention.
Claims (4)
1. A liquid zoom imaging method based on a dielectric elastomer is characterized in that: the planar dielectric elastomer is attached to the bottom surface of the flexible hollow round table; the bottom radius of the flexible hollow round table is driven to change by driving the plane dielectric elastomer to deform, liquid is injected into the flexible hollow round table, flexible electrodes are coated on peripheral areas of the upper surface and the lower surface of the plane dielectric elastomer, when the two flexible electrodes have voltage difference, the area of the plane dielectric elastomer coated with the electrodes is increased, the bottom of the flexible hollow round table is driven to contract, the bottom radius is reduced, and further the shape of the liquid in the flexible hollow round table is changed, wherein the shape comprises the liquid height, the radius and the bow height, so that the focal length of the liquid lens is changed; when the focal length of the liquid lens is changed and the difference of the focal positions of the liquid lens before and after driving is within the half focal depth of the imaging system, the imaging system can change the imaging size more clearly, the zoom imaging function of a single liquid lens driven singly is realized, and the liquid lens zoom lens has the advantages of large zoom range, high response speed, small volume, low cost and simple driving;
the zoom imaging function is realized by combining the plane dielectric elastomer and the flexible hollow round table, the flexible hollow round table has no special requirement on the thickness, a dielectric elastic material is not required to be used, only the plane dielectric elasticity uses the dielectric elastic material, and the plane dielectric elastomer is easy to process, so that the plane dielectric elastomer and the flexible hollow round table are easy to process.
2. A dielectric elastomer based liquid zoom imaging system for implementing a dielectric elastomer based liquid zoom imaging method of claim 1, wherein: the device comprises a fixed transparent flat plate (1), a flexible hollow round table (2), liquid (3), a hollow cylinder (4), an upper fixing plate (5), a planar dielectric elastomer (6), an upper flexible electrode (7), a lower flexible electrode (8), a lower fixing plate (9) and a power supply (10); the plane dielectric elastomer (6) is a plane dielectric elastomer (6) easy to process, an upper fixing plate (5) and a lower fixing plate (9) are used for fixing the plane dielectric elastomer (6), upper flexible electrodes (7) and lower flexible electrodes (8) are uniformly coated on the upper surface and the lower surface of the peripheral area of the plane dielectric elastomer (6), the radius of the central area is the radius of the bottom of the flexible hollow circular truncated cone (2), the upper flexible electrodes are electrically connected with a power supply (10), and the lower flexible electrodes (8) are electrically connected with the ground end; the bottom of the flexible hollow round table (2) is adhered to the central area of the plane dielectric elastomer (6); the hollow cylinder (4) is adhered to the upper fixing plate (5); liquid (3) is injected into the flexible hollow round table (2), and the top of the flexible hollow round table (2) is adhered to the fixed transparent flat plate (1).
3. A dielectric elastomer based liquid zoom imaging system as recited in claim 2, wherein: the working method is that,
the method comprises the following steps: when the switch of the power supply (10) is turned off, the planar dielectric elastomer (6) is not driven because the upper flexible electrode (7) and the lower flexible electrode (8) have no voltage difference, and the radius of the bottom (11) of the flexible hollow circular truncated cone is a1The radius of the top (12) of the flexible hollow round table is b, and the height (13) of the flexible hollow round table is h; the flexible hollow round table (2) is filled with liquid (3), and the height of the liquid surface (15) before the driving of the plane dielectric elastomer (6) is h0Radius r0Bow height s0The volume V of the liquid (3) is then expressed as:
focal length f of liquid lens before driving by plane dielectric elastomer (6)0Expressed as:
after the incident parallel light is acted by the liquid surface (15) before being driven by the dielectric elastomer, the convergent light (17) before being driven is focused on the position of a focus (19) before being driven;
step two: when the switch of the power supply (10) is closed, the planar dielectric elastomer (6) is driven because the upper flexible electrode (7) and the lower flexible electrode (8) have voltage difference, the area of the region of the planar dielectric elastomer (6) coated with the electrodes is increased, the bottom (11) of the flexible hollow circular truncated cone is driven to contract, and the radius of the flexible hollow circular truncated cone is changed into a0(ii) a As the top (12) of the flexible hollow round table is fixed by the fixed transparent flat plate, the cone angle of the flexible hollow round table (2) changes, the shape of the liquid surface (16) after driving changes, and the liquid height changes to h1The radius of the liquid becomes r1Liquid bow height changed to s1(ii) a Because the volume of the liquid (3) is not changed and the contact angle of the liquid (3) -the flexible hollow round table (2) is not changed, simultaneously, according to the triangle geometrical relationship, when the bottom (11) of the flexible hollow round table is changed into a0And (3) calculating three parameters of the height of the liquid, the radius of the liquid and the height of the liquid arch after driving according to the formula (3).
Wherein theta is a contact angle between the liquid and the flexible hollow circular truncated cone. Due to the fact that the height, the liquid radius and the liquid bow height of the liquid after driving are changed, after the incident parallel light rays are acted by the liquid surface after the driving of the dielectric elastic body, the driven converged light rays are focused on the driven focal position. The focal length after driving will also change, and the changed focal length f of the liquid lens1Comprises the following steps:
wherein: f. of1Is the changed focal length of the liquid lens.
In order to enable the liquid lens to realize zoom imaging, the difference between the focal positions of the liquid lens before and after driving should be within the half-focal depth of the imaging system, i.e.
Where is the depth of focus of the imaging system. After the formula (5) is satisfied, the system can be ensured to image clearly, and the zoom ratio of the liquid lens is as follows:
the liquid lens zooming with different zoom ratios is obtained by optimizing the structural parameters of the flexible hollow round table and the initial shape of liquid, so that the single liquid lens zooming function can be realized by single driving by applying voltage on the dielectric elastomer, the flexible hollow round table has no special requirement on the thickness, and the flexible hollow round table is obtained by 3D printing or twice injection molding process, and has the advantage of easy processing.
4. A dielectric elastomer based liquid zoom imaging system as recited in claim 3, wherein: the method also comprises a third step of,
according to different zooming application requirements, the liquid lens (3) has different focal lengths; when the liquid lens (3) has a long focal length and a short focal length, in order to reduce the length of the zoom imaging system, different camera structure modes are required to be adopted to match the liquid lens (3) to complete zoom imaging; under different focal lengths of the liquid lens (3), the imaging modes of the liquid zoom imaging system based on the dielectric elastomer comprise a mode I and a mode II:
the first method is as follows: when the liquid lens (3) in the flexible hollow circular truncated cone (2) has a long focal length, a camera (25) structure comprising a concave lens (22), a convex lens (23) and an image sensor (24) is adopted, wherein the image space focal point of the liquid lens (3) is superposed with the image space focal point of the concave lens (22); incident parallel light rays (14) emitted from an infinite target (21) are converged by a liquid lens (3) in a flexible hollow circular truncated cone (2), then are changed into parallel light rays under the action of a concave lens (22), and finally are focused by a convex lens (23) to be imaged on an image sensor (24);
the second method comprises the following steps: when the liquid lens (3) in the flexible hollow circular truncated cone (2) has a short focal length, a camera (25) structure comprising a convex lens (26), a convex lens (23) and an image sensor (24) is adopted, wherein the image space focal point of the liquid lens (3) is superposed with the object space focal point of the concave lens (22); incident parallel light rays (14) emitted from an infinite target (21) are converged by a liquid lens (3) in a flexible hollow circular truncated cone (2), then are changed into parallel light rays under the action of a convex lens (26), and finally are focused by a convex lens (23) to be imaged on an image sensor (24).
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| CN202010639412.5A CN111751910B (en) | 2020-07-06 | 2020-07-06 | Liquid lens zooming imaging method and system based on dielectric elastomer |
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| CN202010639412.5A CN111751910B (en) | 2020-07-06 | 2020-07-06 | Liquid lens zooming imaging method and system based on dielectric elastomer |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113433605A (en) * | 2021-05-13 | 2021-09-24 | 北京理工大学 | Liquid lens for driving and packaging conductive liquid by dielectric elastomer |
| CN114244984A (en) * | 2021-12-16 | 2022-03-25 | 维沃移动通信有限公司 | Liquid lens module and electronic equipment |
| CN114839763A (en) * | 2022-02-15 | 2022-08-02 | 北京理工大学 | Alvarez lens zooming scanning device based on dielectric elastomer drive |
| CN114839761A (en) * | 2022-02-15 | 2022-08-02 | 北京理工大学 | Non-uniform zooming curved compound eye array based on dielectric elastic drive |
| CN114879287A (en) * | 2022-06-06 | 2022-08-09 | 北京理工大学 | Zoom system and method without mechanical moving part |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101930120A (en) * | 2009-06-26 | 2010-12-29 | 索尼公司 | Lens of variable focal length, camera model and electronic equipment |
| CN107526123A (en) * | 2016-06-21 | 2017-12-29 | 乐金显示有限公司 | Liquid lens and liquid lens module |
| CN111123416A (en) * | 2020-02-13 | 2020-05-08 | 北京理工大学 | Single-drive liquid zoom lens, manufacturing method thereof and zoom imaging method |
| CN111239864A (en) * | 2020-02-13 | 2020-06-05 | 北京理工大学 | Dielectric elastic microfluid liquid lens with sandwich structure and manufacturing method thereof |
-
2020
- 2020-07-06 CN CN202010639412.5A patent/CN111751910B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101930120A (en) * | 2009-06-26 | 2010-12-29 | 索尼公司 | Lens of variable focal length, camera model and electronic equipment |
| CN107526123A (en) * | 2016-06-21 | 2017-12-29 | 乐金显示有限公司 | Liquid lens and liquid lens module |
| CN111123416A (en) * | 2020-02-13 | 2020-05-08 | 北京理工大学 | Single-drive liquid zoom lens, manufacturing method thereof and zoom imaging method |
| CN111239864A (en) * | 2020-02-13 | 2020-06-05 | 北京理工大学 | Dielectric elastic microfluid liquid lens with sandwich structure and manufacturing method thereof |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113433605A (en) * | 2021-05-13 | 2021-09-24 | 北京理工大学 | Liquid lens for driving and packaging conductive liquid by dielectric elastomer |
| CN114244984A (en) * | 2021-12-16 | 2022-03-25 | 维沃移动通信有限公司 | Liquid lens module and electronic equipment |
| CN114244984B (en) * | 2021-12-16 | 2024-03-26 | 维沃移动通信有限公司 | Liquid lens module and electronic equipment |
| CN114839763A (en) * | 2022-02-15 | 2022-08-02 | 北京理工大学 | Alvarez lens zooming scanning device based on dielectric elastomer drive |
| CN114839761A (en) * | 2022-02-15 | 2022-08-02 | 北京理工大学 | Non-uniform zooming curved compound eye array based on dielectric elastic drive |
| CN114839763B (en) * | 2022-02-15 | 2023-03-21 | 北京理工大学 | Alvarez lens zooming scanning device based on dielectric elastomer drive |
| CN114879287A (en) * | 2022-06-06 | 2022-08-09 | 北京理工大学 | Zoom system and method without mechanical moving part |
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