CN118043554A

CN118043554A - Electrostatic actuator

Info

Publication number: CN118043554A
Application number: CN202280065671.9A
Authority: CN
Inventors: 西蒙·库利法; 布鲁诺·贝尔格
Original assignee: Laclaree
Current assignee: Laclaree
Priority date: 2021-09-28
Filing date: 2022-09-19
Publication date: 2024-05-14
Also published as: WO2023052173A1; EP4155540A1

Abstract

The invention relates to an electrostatic actuation device (1) comprising at least one electrode chamber (50), said at least one electrode chamber (50) extending along an extension direction (X) between a first electrode chamber end (51) comprising at least one first fluid channel (31) and a second electrode chamber end (53) comprising at least one second fluid channel (41). The at least one electrode chamber (50) comprises at least one transversal electrode (3, 5) extending transversally along the extension direction (X) and is adapted to house a deformable electrode (55), the deformable electrode (55) being configured to cooperate with the at least one transversal electrode (3, 5) so as to actuate between at least a first position and a second position to push a volume of fluid in opposite directions through at least one channel selected between the at least one first fluid channel (31) and the at least one second fluid channel (41). The invention also relates to spectacles (S) comprising such an electrostatic actuation device (1).

Description

Electrostatic actuator

Technical Field

The present invention relates to the field of liquid displacement devices. More particularly, the present invention relates to electrostatic pumps and, more particularly, to electrostatic actuation devices that use a diaphragm to displace at least one fluid.

Background

It is known from the prior art to use means for displacing a certain amount of fluid, for example using a piezoelectric actuator. The main problem posed by these concepts is that they are generally designed for continuous operation, such as continuous circulation of small flows of liquid through a pipe. They are therefore slow and exhibit very low power efficiency, sometimes reaching power efficiencies of less than 0.1. Therefore, they are not suitable for reversible pumping of limited amounts of liquids and the need to use low power consumption.

A recent solution, for example described in EP3507644A1, suggests the use of a deformable electrode which can be electrostatically actuated between a first position and a second position when cooperating with an actuation electrode. In this way, a limited amount of fluid may be pushed through the fluid passageway intended to pass through the actuation electrode. While this solution allows pushing a limited volume of fluid with low power consumption, it involves the use of a dedicated actuation electrode structure, which increases manufacturing process costs. Furthermore, the overall structure of the electrostatic actuation device presents a high complexity, since the actuation function and the fluid path function are carried by the same component (actuation electrode).

Disclosure of Invention

The present invention aims to solve the above problems. To this end, the invention relates to an electrostatic actuation device comprising at least one electrode chamber; the at least one electrode chamber extends along an extension direction between a first electrode chamber end and a second electrode chamber end, wherein:

-the first electrode chamber end comprises at least one first fluid channel, which is exposed outwards and configured to allow fluid to pass through;

-the second electrode chamber end comprises at least one second fluid channel, which is outwardly exposed and configured to allow fluid to pass through;

-said at least one electrode chamber comprises at least one transverse electrode extending transversely along said extension direction.

The at least one electrode chamber is adapted to receive a deformable electrode configured to cooperate with the at least one lateral electrode so as to be actuated between at least a first position and a second position.

The deformable electrode is configured to push a volume of fluid in a reverse direction through at least one channel selected between the at least one first fluid channel and the at least one second fluid channel when the deformable electrode is actuated between the at least first and second positions.

The electrostatic actuation means described above makes it possible to push the fluid contained in the electrode chamber outwards in a reverse direction by actuating the deformable electrode. Such electrostatic actuation means may for example be used to control the optical power of a fluid lens.

Such a dedicated structure of the at least one electrode chamber, in which at least one transversal electrode extends transversally to the extension direction, not only allows a better control of the fluid movement, but also allows a simplification of the overall structure of the electrode chamber.

In fact, separating the actuation function of the transverse electrode from the fluid path functions of the first and second fluid channels facilitates the manufacture and assembly of the electrostatic actuation device.

According to embodiments, the electrostatic actuation device comprises one or more of the following features, alone or in combination.

According to one embodiment, the electrostatic actuation device is configured to push only a limited volume.

According to one embodiment, the electrostatic actuation device comprises a power supply configured to actuate the deformable electrode and a voltage controller configured to supply alternating current and/or alternating voltage from the power supply to the deformable electrode. For example, the alternating current and/or alternating voltage is applied between the deformable electrode and the transverse electrode.

According to an embodiment, the deformable electrode is arranged in at least one electrode chamber so as to divide the at least one electrode chamber into a first electrode compartment and a second electrode compartment.

It will be appreciated that the first electrode compartment and the second electrode compartment are different.

According to one embodiment, the first electrode compartment is fluidly isolated from the second electrode compartment. In other words, according to one embodiment, the first electrode compartment is not in fluid communication with the second electrode compartment.

The arrangement described above makes it possible to simultaneously push a volume of fluid from the first electrode compartment to the outside and suck the same volume of fluid into the second electrode compartment in opposite directions when the deformable electrode is actuated between the first and second positions.

According to one embodiment, the deformable electrode comprises a deformable dielectric layer and at least one conductive portion.

Thus, this configuration allows the deformable electrode to be displaced via the electric field.

According to one embodiment, the at least one electrode chamber has a size of less than 600 μm.

The above arrangement makes it possible to design a micrometric electrostatic actuation device suitable for integration in a wearable device. For example, the electrostatic actuation device is suitable for mounting on a microfluidic device for biological applications, testing, diagnostics, medical devices. Such medical devices include contact lenses, intraocular implants, and also include non-optical medical devices such as small electrostatic actuation devices for drug delivery or small electrostatic actuation devices for external biological fluid analysis and implantation into living subjects.

Furthermore, this configuration allows for a stronger pumping pressure for different fluids.

According to one embodiment, the size of the at least one electrode chamber smaller than 600 μm corresponds to the size of the separation of the two opposing lateral electrodes.

According to one embodiment, the electrostatic actuation means may be implemented on all devices requiring a limited amount of fluid to be pushed with small power consumption.

According to one embodiment, the electrostatic actuation device may be used to control the optical power of a fluid lens embedded in the eyewear.

According to an embodiment, the at least one lateral electrode comprises an insulating layer configured to at least partially electrically insulate the at least one lateral electrode from the deformable electrode.

Thus, direct contact between the deformable electrode and at least one lateral electrode may be avoided to suppress any shorting problem between the deformable electrode and the lateral electrode.

According to an embodiment, the at least one electrode chamber comprises two transverse electrodes arranged opposite to each other compared to the deformable electrode.

According to an embodiment, the at least one lateral electrode comprises a printed circuit board.

The above arrangement makes it possible to reduce the industrial cost and the manufacturing cost of the at least one lateral electrode.

According to one embodiment, the printed circuit board includes a substrate on which a thin metal layer is deposited to form an electrode or a plurality of conductive paths.

According to one embodiment, the thin metal layer comprises at least one metal selected from copper, nickel, silver, gold or equivalents.

According to one embodiment, the substrate comprises a metal plate or epoxy glass.

According to one embodiment, the substrate comprises a polymeric sheet, such as a polyethylene terephthalate (PET) sheet, a Polytetrafluoroethylene (PTFE) sheet, or the like.

According to one embodiment, the transverse electrode is a flat plate transverse electrode.

According to one embodiment, the lateral electrode comprises two opposite ends, each end being provided with a conductive pad configured to be electrically connected to a power source.

According to an embodiment, the at least one lateral electrode exhibits a roughness index lower than 1 μm, more particularly lower than 50nm.

The use of polished transverse electrodes not only allows for increased surface capacitance to improve actuation efficiency, but also allows for a wider deformation of the deformable electrode upon contact with the transverse electrode. When slight deformation causes relatively large fluid displacement, it is particularly useful for micrometer devices.

According to an embodiment, the electrostatic actuation device comprises:

-at least one first chamber comprising a first main fluid passage; the first main fluid aisle is exposed outwards;

-at least one second chamber, different from the at least one first chamber, and comprising a second main fluid passage; the second main fluid aisle is exposed outwardly.

The at least one electrode chamber is disposed between the at least one first chamber and the at least one second chamber, the at least one first fluid passage is configured to allow fluid to pass between the at least one electrode chamber and the at least one first chamber, and the at least one second fluid passage is configured to allow fluid to pass between the at least one electrode chamber and the at least one second chamber.

According to one embodiment, the first main fluid channel emerges outwardly from the electrostatic actuation device.

According to one embodiment, the second main fluid channel emerges outwardly from the electrostatic actuation device.

According to one embodiment, the at least one electrode chamber is enclosed between the first chamber and the second chamber.

According to an embodiment, the at least one electrode chamber comprises a first dividing wall defined adjacent to the first chamber and a second dividing wall defined adjacent to the second chamber, the first dividing wall comprising the at least one first fluid channel and the second dividing wall comprising the at least one second fluid channel.

According to one embodiment, the distance between the first and second partition walls is comprised between 5mm and 10 mm.

According to one embodiment, the first electrode compartment is at least partially defined by the first dividing wall, the deformable electrode and the at least one transverse electrode.

According to one embodiment, the second electrode compartment is at least partially defined by the second partition wall, the deformable electrode and the at least one transverse electrode.

According to an embodiment, at least one of the partition walls selected between the first partition wall and the second partition wall is formed by a column arranged between two lateral electrodes.

For example, the pillars may be formed of a polymeric material deposited by any suitable manufacturing method including, for example, photolithography, screen printing, inkjet printing, or the like.

According to an embodiment, the first partition wall is arranged opposite to the second partition wall compared to the deformable electrode.

According to one embodiment, the first and second partition walls define two transverse sides of the electrode chamber, and two opposing transverse electrodes define two transverse sides of the electrode chamber.

According to one embodiment, the electrode chamber presents a general shape of a parallelepiped, each of the first, second and at least one transversal electrode defining a side of the parallelepiped, respectively.

According to one embodiment, the electrode chamber has a cubic shape.

According to one embodiment, the electrode chamber has a rectangular parallelepiped shape.

According to one embodiment, the electrode chamber has a trapezoidal shape.

It will be appreciated that fluid evacuation or pumping from the electrode chamber is achieved laterally through the at least one first fluid passage and through the at least one second fluid passage. Thus, the electrostatic actuation device exhibits reduced fluid response time.

According to an embodiment, the electrostatic actuation device comprises a plurality of electrode chambers, each of the first partition walls of each of the plurality of electrode chambers comprising at least one first fluid channel configured to allow fluid to pass to a unique first chamber, the first chamber being common to the plurality of electrode chambers, and each of the second partition walls of each of the plurality of electrode chambers comprising at least one second fluid channel configured to allow fluid to pass to a unique second chamber, the second chamber being common to the plurality of electrode chambers.

According to an embodiment, the electrode chambers of the plurality of electrode chambers are stacked adjacent to each other.

According to an embodiment, each electrode chamber is stacked along one of the at least one lateral electrode to any other adjacent electrode chamber.

According to an embodiment, each electrode chamber shares at least one transverse electrode with any other adjacent electrode chamber.

The above arrangement makes it possible to propose a compact electrostatic actuation device.

According to one embodiment, the shared transverse electrode comprises a flat substrate comprising two opposite flat surfaces each covered by a thin metal layer. Thus, one single transverse electrode may be used as the transverse electrode of two adjacent electrode chambers of the stack.

According to this embodiment, the two opposing thin metal layers are electrically connected by at least one via provided through the flat substrate of the lateral electrode.

According to one embodiment, the two opposing thin metal layers are electrically isolated from each other.

According to an embodiment, each deformable electrode comprised in each of the plurality of electrode chambers is actuated separately compared to any other deformable electrode.

The above arrangement makes it possible to adjust the actuation of the electrostatic actuation means by actuating each deformable electrode more precisely.

According to an embodiment, the plurality of electrode chambers comprises a first electrode chamber defining a primary internal volume and a second electrode chamber defining a secondary internal volume, the primary internal volume being entirely different from the secondary internal volume.

In other words, the internal volume of each of the plurality of electrode chambers varies.

Advantageously, the electrostatic actuation means comprise electrode chambers having different internal volumes. Thus, each electrode chamber can be independently actuated to push the appropriate volume of fluid in the opposite direction.

According to one embodiment, the distance between the first and second partition walls of one electrode chamber is varied compared to the distance between the first and second partition walls of the other electrode chamber.

According to one embodiment, the distance between the two lateral electrodes of one electrode chamber is varied compared to the distance between the two lateral electrodes of the other electrode chamber.

According to one embodiment, the first electrode compartment defines a first volume and the second electrode compartment defines a second volume; the first volume and the second volume are controlled by capacitance measurement.

Thus, this configuration allows to control the first volume and/or the second volume more precisely by capacitance measurement by measuring the frequency of, for example, a capacitive dependent relaxation oscillator.

The object of the invention is also achieved by implementing spectacles comprising an electrostatic actuation device according to one of the embodiments described above.

Drawings

The foregoing and other objects, features, aspects and advantages of the present invention will become apparent from the following detailed description of embodiments, which is to be read in connection with the accompanying drawings, wherein like characters designate like elements or elements having similar functions, by way of illustration and not limitation, and wherein:

fig. 1 shows a cross-sectional view of an electrostatic actuation device comprising a single electrode chamber according to a first embodiment.

Fig. 2 shows two perspective views of the electrostatic actuation device, showing the first and second primary fluid passages.

Fig. 3 shows a perspective view of an electrode chamber including a post.

Fig. 4 shows a cross-sectional view of an electrostatic actuation device comprising three electrode chambers according to a second embodiment.

Fig. 5 shows a cross-sectional view of an electrostatic actuation device comprising four electrode chambers according to a third embodiment.

Fig. 6 shows a perspective view of a pair of spectacles comprising two electrostatic actuation devices according to the present invention.

Detailed Description

In the drawings and the rest of the specification, the same reference numerals refer to the same or similar elements. Furthermore, the various elements are not shown to scale to facilitate clarity of the drawing. Furthermore, the different embodiments and variants are not mutually exclusive and can be combined with one another.

As shown in fig. 1 to 6, the present invention relates to an electrostatic actuation device 1 which can be used to control the optical power of a fluid lens. More generally, the electrostatic actuation device 1 may be implemented on all devices that require a limited amount of fluid to be pushed with little power consumption. The invention also relates to spectacles S comprising said electrostatic actuation device 1.

As shown in fig. 1, the electrostatic actuation device 1 comprises at least one electrode chamber 50, the electrode chamber 50 extending along an extension direction X between a first electrode chamber end 51 and a second electrode chamber end 53. The first electrode chamber end 51 includes at least one first fluid channel 31, the first fluid channel 31 being exposed outwardly and configured to allow a fluid (e.g., a first fluid) to pass therethrough. The second electrode chamber end 53 includes at least one second fluid channel 41, the second fluid channel 41 being exposed outwardly and configured to allow a fluid (e.g., a second fluid) to pass therethrough.

The electrostatic actuation device 1 may further comprise at least one first chamber 10 and at least one second chamber 20 different from the at least one first chamber 10. The at least one electrode chamber 50 is arranged between the at least one first chamber 10 and the at least one second chamber 20 such that the at least one electrode chamber 50 is enclosed between the first chamber 10 and the second chamber 20. Thus, the at least one first fluid channel 31 is configured to allow a first fluid to pass between the at least one electrode chamber 50 and the at least one first chamber 10, and the at least one second fluid channel 41 is configured to allow a second fluid to pass between the at least one electrode chamber 50 and the at least one second chamber 20. As shown in fig. 2, the at least one first chamber 10 may then comprise a first main fluid passage 12 emerging outwardly from the electrostatic actuation device 1, and the at least one second chamber 20 may comprise a second main fluid passage 14 emerging outwardly from the electrostatic actuation device 1.

The at least one electrode chamber 50 further comprises at least one transverse electrode 3,5 extending transversely to the extension direction X. Fig. 1 shows an embodiment of an electrostatic actuation device 1 comprising a first transverse electrode 3 and a second transverse electrode 5. Further, the electrode chamber 50 may include a longitudinal wall extending longitudinally to the electrode chamber 50 along the extending direction X.

The at least one electrode chamber 50 may also include a first dividing wall 30 defined adjacent the first chamber 10 and a second dividing wall 40 defined adjacent the second chamber 20. According to the embodiment shown in fig. 1, the first separation wall 30 is arranged at the first electrode chamber end 51, while the second separation wall 40 is arranged at the second electrode chamber end 53. Therefore, the first partition wall 30 is arranged opposite to the second partition wall 40, as compared to the deformable electrode 55. Thus, the first partition wall 30 may comprise the at least one first fluid channel 31, while the second partition wall 40 may comprise the at least one second fluid channel 41. According to a first variant, the distance between the first partition wall 30 and the second partition wall 40 is comprised between 5mm and 10 mm.

As shown in fig. 3, at least one partition wall selected between the first partition wall 30 and the second partition wall 40 is formed of a column arranged between the two lateral electrodes 3, 5. For example, the pillars may be formed of a polymeric material deposited by any suitable manufacturing method including, for example, photolithography, screen printing, inkjet printing, or the like.

According to one embodiment, the electrode chamber 50 presents a substantially parallelepiped shape, for example a cubic, cuboid or trapezoidal shape. Each of the first partition wall 30, the second partition wall 40, the longitudinal wall and the at least one transverse electrode 3, 5 defines a side of said parallelepiped, respectively. The first and second partition walls 30, 40 may define two transverse sides of the electrode chamber 50, and the two opposing transverse electrodes 3, 5 may define two transverse sides of the electrode chamber 50. In the variant shown in fig. 1, the first and second partition walls 30, 40 extend substantially parallel with respect to each other and substantially perpendicular to the direction of extension X. Furthermore, the first and second transverse electrodes 3, 5 extend substantially parallel with respect to each other and substantially perpendicular to a transversal direction Y defined perpendicularly to the extension direction X. Advantageously, the at least one electrode chamber 50 may have a size of less than 600 μm. In particular, the dimensions of the at least one electrode chamber smaller than 600 μm may correspond to the dimensions of the separation of the two opposite lateral electrodes 3, 5.

As shown in fig. 1, each transverse electrode 3, 5 is a plate-like transverse electrode 3, 5, and may include a printed circuit board. Thus, the industrial cost and the manufacturing cost of the at least one transversal electrode 3, 5 can be reduced. The printed circuit board may include a substrate 4, a thin metal layer 6 deposited on the substrate 4 to form an electrode or a plurality of conductive paths. For example, the substrate 4 comprises a metal plate, an epoxy glass or a polymer plate, such as polyethylene terephthalate (PET), polytetrafluoroethylene (PTFE) or equivalent. The thin metal layer 6 may include at least one metal selected from copper, nickel, silver, gold, or equivalents. Advantageously, the at least one transversal electrode 3, 5 may exhibit a roughness index lower than 1 μm, more particularly lower than 50 nm. In other words, the at least one transverse electrode 3, 5 may present an active surface directed towards the interior of the electrode chamber 50, said active surface presenting a roughness lower than 1 μm, more particularly lower than 50 nm.

The at least one electrode chamber 50 is further adapted to house a deformable electrode 55. According to one embodiment, the deformable electrode 55 is arranged in the at least one electrode chamber 50 so as to divide the at least one electrode chamber 50 into a first electrode compartment 57 and a second electrode compartment 59. It should be appreciated that the first electrode compartment 57 and the second electrode compartment 59 are different. Advantageously, the first electrode compartment 57 is fluidly isolated from the second electrode compartment 59. In other words, the first electrode compartment 57 is not in fluid communication with the second electrode compartment 59. The first electrode compartment 57 is then at least partly delimited by the first separation wall 30, the deformable electrode 55 and the at least one transverse electrode 3, 5. The second electrode compartment 59 is at least partially delimited by the second partition wall 40, the deformable electrode 55 and the at least one transverse electrode 3, 5.

The deformable electrode 55 is configured to cooperate with the at least one transverse electrode 3, 5 so as to be actuated between at least a first position and a second position. In this way, when the deformable electrode 55 is actuated between the at least first and second positions, the deformable electrode 55 is able to push a volume of fluid in reverse through at least one channel selected between the at least one first fluid channel 31 and the at least one second fluid channel 41. To perform such actuation, the electrostatic actuation device 1 comprises a power supply 2 configured to actuate the deformable electrode 55 and a voltage controller configured to supply an alternating current and/or an alternating voltage from the power supply 2 to the deformable electrode 55. In the particular embodiment shown in fig. 1, the electrode chamber 50 comprises two transverse electrodes 3, 5 arranged opposite to each other, in contrast to the deformable electrode 55. For example, each lateral electrode 3, 5 may comprise two opposite ends, each provided with a conductive pad configured to be electrically connected to the power supply 2. The arrangement described above is such that when the deformable electrode is actuated between the first and second positions, a volume of fluid can be simultaneously pushed from the first electrode compartment 57 to the outside and the same volume of fluid drawn into the second electrode compartment 59 in opposite directions. According to one embodiment, the first electrode compartment 57 may define a first volume and the second electrode compartment 59 may define a second volume. According to this embodiment, the first volume and the second volume may be controlled by capacitance measurement. Thus, this configuration allows to control the first volume and/or the second volume more precisely by capacitance measurement by measuring the frequency of, for example, a capacitive dependent relaxation oscillator.

Actuation of the deformable electrode 55 to push a volume of fluid is achieved, for example, according to the embodiment described in EP3507644A1 (which is incorporated herein by reference to the maximum extent allowed by law). The dashed arrows shown in fig. 1 illustrate examples of movement of the first and second fluids when the deformable electrode 55 is actuated between the first and second positions. When the deformable electrode 55 is also actuated in the other direction, the first fluid and the second fluid may in fact also be pushed in opposite directions.

The above configuration allows for a stronger pumping pressure for different fluids. It will be appreciated that fluid evacuation or pumping from the electrode chamber 50 is achieved laterally through the at least one first fluid channel 31 and through the at least one second fluid channel 41. Thus, the electrostatic actuation device 1 exhibits a reduced fluid response time.

Advantageously, the deformable electrode 55 may comprise a deformable dielectric layer 551 and at least one conductive portion 553. Thus, this configuration allows the deformable electrode 55 to be displaced via an electric field.

As previously mentioned, the lateral electrodes 3, 5 may exhibit a roughness of less than 1 μm or less than 50 nm. Thus, the use of polished lateral electrodes 3, 5 not only allows for an increase in surface capacitance to improve actuation efficiency, but also allows for a more extensive deformation of the deformable electrode 55 upon contact with the lateral electrodes 3, 5. When slight deformation causes relatively large fluid displacement, it is particularly useful for micrometer devices.

Typically, the at least one lateral electrode 3, 5 comprises an insulating layer 7, the insulating layer 7 being configured to at least partially electrically insulate the at least one lateral electrode 3, 5 from the deformable electrode 55. Thus, direct contact between the deformable electrode 55 and the at least one lateral electrode 3, 5 can be avoided to suppress any short-circuit problems between said deformable electrode 55 and said lateral electrode 3, 5.

The electrostatic actuation device 1 described above makes it possible to push the fluid contained in the electrode chamber 50 outwards in a reverse direction by actuation of the deformable electrode 55. For example, the electrostatic actuation device 1 may be configured to push only a limited volume. Such an electrostatic actuation device 1 may for example be used to control the optical power of a fluid lens. Such a dedicated structure of the at least one electrode chamber 50, in which at least one transversal electrode 3, 5 extends transversally to the extension direction X, not only allows a better control of the fluid movement, but also allows a simplification of the overall structure of the electrode chamber 50. In fact, separating the actuation function of the transversal electrodes 3, 5 from the fluid path function of the first 31 and second 41 fluid channels facilitates the manufacture and assembly of the electrostatic actuation device 1.

The small size of the whole device makes it possible to design a micrometric electrostatic actuation device 1 suitable for integration in a wearable device. For example, the electrostatic actuation device 1 is suitable for mounting on a microfluidic device for biological applications, testing, diagnostics, medical devices. Such medical devices include contact lenses, intraocular implants, and also include non-optical medical devices such as small electrostatic actuation devices for drug delivery or small electrostatic actuation devices for external biological fluid analysis and implantation into living subjects.

According to another embodiment, illustrated in fig. 4 and 5, the electrostatic actuation device 1 may comprise a plurality of electrode chambers 50. Each of the first dividing walls 30 of each electrode chamber 50 of the plurality of electrode chambers 50 comprises at least one first fluid channel 31, the first fluid channel 31 being configured to allow fluid to pass to a unique first chamber 10, said first chamber 10 being common to the plurality of electrode chambers 50. Similarly, each of the second partition walls 40 of each electrode chamber 50 of the plurality of electrode chambers 50 comprises at least one second fluid channel 41, the second fluid channel 41 being configured to allow fluid to pass to a unique second chamber 20, said second chamber 20 being common to the plurality of electrode chambers 50. Advantageously, the electrode chambers 50 of the plurality of electrode chambers 50 are stacked adjacent to each other, for example along one of the at least one transverse electrode 3, 5. The above arrangement makes it possible to propose a compact electrostatic actuation device 1.

In the particular embodiment shown in fig. 5, each electrode chamber 50 shares at least one transverse electrode 3, 5 with any other adjacent electrode chamber 50. Thus, the first electrode chamber 50a comprises an upper transverse electrode 3a and a lower transverse electrode 5a. The second electrode chamber 50b adjacent to the first electrode chamber 50a comprises an upper transverse electrode 3b in common with a lower transverse electrode 5a. The shared lateral electrode 3b, 5a comprises a flat substrate 4, the flat substrate 4 comprising two opposite flat surfaces each covered by a thin metal layer 6. Thus, one single transverse electrode 3b, 5a may be used as the transverse electrode 3b, 5a of two adjacent stacked electrode chambers 50a, 50 b. By sharing the upper lateral electrode 3c of the third electrode chamber 50c and the lower lateral electrode 5b of the second electrode chamber 50b, a corresponding stacked structure can be achieved between the second electrode chamber 50b and the third electrode chamber 50 c. Finally, by sharing the upper lateral electrode 3d of the fourth electrode chamber 50d and the lower lateral electrode 5c of the third electrode chamber 50c, a similar stacked structure can be achieved between the third electrode chamber 50c and the fourth electrode chamber 50 d. According to one embodiment, two opposing thin metal layers 6 sharing the lateral electrodes 3, 5 may be electrically connected via at least one via provided through the flat substrate 4 of the lateral electrodes 3, 5.

Advantageously, each deformable electrode 55a-55d included in each electrode chamber 50 of the plurality of electrode chambers 50 is actuated separately compared to any other deformable electrode 55. The above arrangement makes it possible to adjust the actuation of the electrostatic actuation device 1 by actuating each deformable electrode 55 more precisely.

Further, when the plurality of electrode chambers 50 includes a first electrode chamber 50a and a second electrode chamber 50b, it is contemplated that the first electrode chamber 50a defines a primary internal volume and the second electrode chamber 50b defines a secondary internal volume that is entirely different from the primary internal volume. In other words, the internal volume of each electrode chamber 50 of the plurality of electrode chambers 50 may vary. Thus, when the electrostatic actuation device 1 comprises electrode chambers 50 having different internal volumes, each electrode chamber 50 can be independently actuated to push the appropriate volume of fluid in the opposite direction. In order to adjust the internal volume of each electrode chamber 50, the distance between the first and second partition walls 30 and 40 of one first electrode chamber 50a may be varied as compared to the distance between the first and second partition walls 30 and 40 of the other electrode chamber 50. At the same time or different therefrom, the distance between the two transverse electrodes 3, 5 of one electrode chamber 50 may be varied compared to the distance between the two transverse electrodes 3, 5 of the other electrode chamber 50 to adjust the internal volume of each electrode chamber 50.

Claims

1. An electrostatic actuation device (1) comprising at least one electrode chamber (50); the at least one electrode chamber (50) extends along an extension direction (X) between a first electrode chamber end (51) and a second electrode chamber end (53), wherein:

-the first electrode chamber end (51) comprises at least one first fluid channel (31), the at least one first fluid channel (31) being outwardly exposed and configured to allow fluid to pass through;

-the second electrode chamber end (53) comprises at least one second fluid channel (41), the at least one second fluid channel (41) being outwardly exposed and configured to allow fluid to pass through;

-said at least one electrode chamber (50) comprises at least one transversal electrode (3, 5) extending transversally along said extension direction (X);

the at least one electrode chamber (50) is adapted to house a deformable electrode (55), the deformable electrode (55) being configured to cooperate with the at least one transverse electrode (3, 5) so as to be actuated between at least a first position and a second position;

the deformable electrode (55) is configured to push a volume of fluid in reverse through at least one channel selected between the at least one first fluid channel (31) and the at least one second fluid channel (41) when the deformable electrode (55) is actuated between the at least first and second positions.

2. The electrostatic actuation device (1) according to claim 1, wherein the deformable electrode (55) is arranged in at least one electrode chamber (50) so as to divide the at least one electrode chamber (50) into a first electrode compartment (57) and a second electrode compartment (59).

3. The electrostatic actuation device (1) according to any one of claims 1 or 2, wherein the at least one electrode chamber (50) has a size of less than 600 μιη.

4. An electrostatic actuation device (1) according to any one of claims 1 to 3, wherein the at least one lateral electrode (3, 5) comprises an insulating layer (7), the insulating layer (7) being configured to at least partially electrically insulate the at least one lateral electrode (3, 5) from the deformable electrode (55).

5. The electrostatic actuation device (1) according to any one of claims 1 to 4, wherein the at least one electrode chamber (50) comprises two transverse electrodes (3, 5) arranged opposite each other compared to the deformable electrode (55).

6. The electrostatic actuation device (1) according to any one of claims 1 to 5, wherein the at least one transverse electrode (3, 5) comprises a printed circuit board.

7. The electrostatic actuation device (1) according to claim 6, wherein the at least one transverse electrode (3, 5) exhibits a roughness index lower than 1 μm, more particularly lower than 50nm.

8. The electrostatic actuation device (1) according to any one of claims 1 to 7, comprising:

-at least one first chamber (10) comprising a first main fluid passage (12); the first main fluid aisle (12) is exposed outwards;

-at least one second chamber (20), the at least one second chamber (20) being different from the at least one first chamber (10) and comprising a second main fluid aisle (14); the second main fluid aisle (14) is exposed outwards;

The at least one electrode chamber (50) is arranged between the at least one first chamber (10) and the at least one second chamber (20), the at least one first fluid channel (31) is configured to allow fluid to pass between the at least one electrode chamber (50) and the at least one first chamber (10), and the at least one second fluid channel (41) is configured to allow fluid to pass between the at least one electrode chamber (50) and the at least one second chamber (20).

9. The electrostatic actuation device (1) according to claim 8, wherein the at least one electrode chamber (50) comprises a first separation wall (30) defined adjacent to the first chamber (10) and a second separation wall (40) defined adjacent to the second chamber (20), the first separation wall (30) comprising the at least one first fluid channel (31) and the second separation wall (40) comprising the at least one second fluid channel (41).

10. Electrostatic actuation device (1) according to claims 5 and 9, wherein at least one partition wall selected between the first partition wall (30) and the second partition wall (40) is formed by a column arranged between the two transverse electrodes (3, 5).

11. The electrostatic actuation device (1) according to any one of claims 9 or 10, wherein the first separation wall (30) is arranged opposite the second separation wall (40) compared to the deformable electrode (55).

12. The electrostatic actuation device (1) according to any one of claims 9 to 11, comprising a plurality of electrode chambers (50), each of the first partition walls (30) of each electrode chamber (50) of the plurality of electrode chambers (50) comprising at least one first fluid channel (31), the at least one first fluid channel (31) being configured to allow fluid to pass to a unique first chamber (10), the first chamber (10) being common to the plurality of electrode chambers (50), and wherein each of the second partition walls (40) of each electrode chamber (50) of the plurality of electrode chambers (50) comprises at least one second fluid channel (41), the at least one second fluid channel (41) being configured to allow fluid to pass to a unique second chamber (20), the second chamber (20) being common to the plurality of electrode chambers (50).

13. The electrostatic actuation device (1) according to claim 12, wherein electrode chambers (50) of the plurality of electrode chambers (50) are stacked adjacent to each other.

14. The electrostatic actuation device (1) according to claim 13, wherein each electrode chamber (50) is stacked to any other adjacent electrode chamber (50) along one of the at least one transverse electrode (3, 5).

15. The electrostatic actuation device (1) according to any one of claims 12 to 14, wherein each electrode chamber (50) shares at least one transverse electrode (3, 5) with any other adjacent electrode chamber (50).

16. The electrostatic actuation device (1) according to any one of claims 12 to 15, wherein each deformable electrode (55) comprised in each electrode chamber (50) of the plurality of electrode chambers (50) is actuated separately compared to any other deformable electrode (55).

17. The electrostatic actuation device (1) according to claims 12 to 16, wherein the plurality of electrode chambers (50) comprises a first electrode chamber (50 a) defining a primary internal volume and a second electrode chamber (50 b) defining a secondary internal volume, the primary internal volume being completely different from the secondary internal volume.

18. Glasses (S) comprising an electrostatic actuation device (1) according to any one of claims 1 to 17.