This disclosure relates to the field of displacement devices for liquids. More specifically, this disclosure deals with electrostatics pump and precisely with electrostatics actuated devices using a membrane to displace at least one fluid.
It is known from the state of the art to use devices for displacing an amount of fluid using piezoelectric actuators for instance. The main problem raised by these concepts is that they are usually designed for continuous operations like circulating continuously small fluxes of liquids through a pipe. Therefore they are slow, and exhibit very low power efficiency, sometimes reaching a power efficiency less than 0.1. Consequently, they are not adapted to the need of the reversible pumping of a limited quantity of liquid and using low power consumption.
A recent solution described for example in EP3507644A1 suggest using a deformable electrode that may be electrostatically actuated between a first position and a second position when cooperating with an actuation electrode. By this way, a limited amount of fluid may be pushed through fluid passages intended through the actuation electrode. Although this solution allows pushing a limited volume of fluid with low power consumption, it involves using a dedicated actuation electrode structure, which can increase the manufacturing process costs. Further, the overall structure of the electrostatically actuated device presents a high complexity since the actuation function and the fluidic path function are bear by the same component: the actuation electrode.
The present disclosure aim at solving the aforementioned problems. To this end, the present disclosure concerns an electrostatically actuated device comprising at least one electrode chamber; said at least one electrode chamber extending along a direction of extension between a first electrode chamber end and a second electrode chamber end, wherein:
The at least one electrode chamber is adapted to receive a deformable electrode, said deformable electrode being configured to cooperate with the at least one lateral electrode such as to be actuated between at least a first position and a second position.
The deformable electrode is configured to push reversely a volume of fluid through at least one channel chosen 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 position and the second position.
The electrostatically actuated device described above make it possible to push reversely fluids contained in the electrode chamber outwardly by actuation of the deformable electrode. Such electrostatically actuated device may for example be used to control the optical power of fluid lens.
The dedicated structure of the at least one electrode chamber with at least one lateral electrode extending laterally to the direction of extension allows both to have a better control of fluid movements and to simplify the overall structure of the electrode chamber.
Indeed dissociating the actuating function of the lateral electrode and the fluidic path function of the first fluid channel and the second fluid channel facilitate the electrostatically actuated device manufacturing and assembly.
According to an embodiment, the electrostatically actuated device comprises one or more of the following features, taken alone or in combination.
According to one embodiment, the electrostatically actuated device is configured to push a limited volume only.
According to one embodiment, the electrostatically actuated device comprises a power supply configured to actuate the deformable electrode and a voltage controller configured to supply an alternative current and/or an alternative voltage from the power supply to the deformable electrode. For example, said alternative current and/or an alternative voltage is applied between the deformable electrode and the lateral electrode.
According to an embodiment, the deformable electrode is disposed in at least one electrode chamber such as to partition the at least one electrode chamber in a first electrode compartment, and a second electrode compartment.
It is well understood that the first electrode compartment and the second electrode compartment are distinct.
According to one embodiment, the first electrode compartment is fluidly isolated from the second electrode compartment. In others words, according to one embodiment, the first electrode compartment does not fluidly communicate to the second electrode compartment.
The arrangements described above make it possible to simultaneously and reversely push a volume of fluid outside from the first electrode compartment, and to suck the same volume of fluid in the second electrode compartment when the deformable is actuated between the first position and the second position.
According to one embodiment, the deformable electrode comprises a deformable dielectric layer and at least one electroconducting portion.
Thus, this configuration allows having a displacement of the deformable electrode via an electric field.
According to an embodiment, a dimension of the at least one electrode chamber is smaller than 600 μm.
The arrangements described above make it possible to design a micrometric electrostatically actuated device, adapted to be integrated in wearable device. For example, the electrostatically actuated device is adapted to be mounted on microfluidic devices for biological applications, tests, diagnosis, medical devices. Such medical devices include contact lenses, intraocular implants but also non-optical medical devices like small electrostatically actuated devices for drug delivery of small electrostatically actuated devices for biological fluids analysis external as well as implanted in a living body.
Besides, such configuration allows having a stronger pumping pressure on the different fluids.
According to one embodiment, the dimension of the at least one electrode chamber being less than 600 μm corresponds to the dimensions separating two opposite lateral electrodes.
According to one embodiment, the electrostatically actuated device may be implemented on all apparatus where a limited amount of fluid needs to be pushed with small power consumption.
According to one embodiment, the electrostatically actuated device may be used to control the optical power of fluid lens embedded in spectacles.
According to an embodiment, the at least one lateral electrode comprises an insulating layer configured to electrically insulate at least partially the at least one lateral electrode from the deformable electrode.
Thus, is possible to avoid direct contact between the deformable electrode and the at least one lateral electrode, to suppress any short-cut issue between said deformable electrode and said lateral electrode.
According to an embodiment, the at least one electrode chamber comprises two lateral electrodes disposed 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 arrangements described above make it possible to reduce the industrial and manufacturing costs of the at least one lateral electrode.
According to one embodiment, the printed circuit board comprises a substrate on which a thin metallic layer is deposited to form an electrode or a plurality of conducting paths.
According to one embodiment, the thin metallic layer comprises at least one metal chosen between copper, nickel, silver, gold, or equivalent.
According to one embodiment, the substrate comprises a metallic plate, or an epoxy glass.
According to one embodiment, the substrate comprises a polymer plate, for example a polyethylene terephthalate (PET) plate, a polytetrafluoroethylene (PTFE) plate, or equivalent.
According to one embodiment, the lateral electrode is a plate lateral electrode.
According to one embodiment, the lateral electrode comprises two opposite extremities, each extremity being provided with a conducting pad configured to be electrically connected to the power supply.
According to an embodiment, the at least one lateral electrode presents a roughness index inferior to 1 μm, and more particularly inferior to 50 nm.
Using a polished lateral electrode allows both to increase the surface capacitance to improve the actuation efficiency, and to allow broader deformation of the deformable electrode when entering in contact with the lateral electrode. It is particularly suitable with micrometric devices when a slight deformation induces a relative large fluidic displacement.
According to an embodiment, the electrostatically actuated device comprises:
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 channel being configured to allow the passage of a fluid between the at least one electrode chamber and the at least one first chamber, and the at least one second fluid channel is configured to allow the passage of a fluid between the at least one electrode chamber and the at least one second 5 chamber.
According to one embodiment, the first primary fluid passage is emerging outwardly from the electrostatically actuated device.
According to one embodiment, the second primary fluid passage is emerging outwardly from the electrostatically actuated device.
According to one embodiment, the at least one electrode chamber is encapsulated between the first chamber and the second chamber.
According to an embodiment, the at least one electrode chamber comprises a first partition wall defined adjacent to the first chamber and a second partition wall defined adjacent to the second chamber, said first partition wall comprising the at least one first fluid channel, and said second partition wall comprising the at least one second fluid channel.
According to one embodiment, a distance between the first partition wall and the second partition wall is comprised between 5 mm and 10 mm.
According to one embodiment, the first electrode compartment is delimited at least partially by the first partition wall, the deformable electrode, and the at least one lateral electrode.
According to one embodiment, the second electrode compartment is delimited at least partially by the second partition wall, the deformable electrode, and the at least one lateral electrode.
According to an embodiment, at least one partition wall chosen between the first partition wall and the second partition wall is formed by pillars disposed between the two lateral electrodes.
For example, said pillars may be formed by a polymer material deposited by any suitable manufacturing method including for example lithography, screen-printing, inkjet printing or equivalent.
According to an embodiment, the first partition wall is disposed opposite to the second partition wall compared to the deformable electrode.
According to one embodiment, the first partition wall, and the second partition wall define two transversal sides of the electrode chamber, and two opposite lateral electrodes define two lateral side of the electrode chamber.
According to one embodiment, the electrode chamber present a general shape of a parallelepiped, each of the first partition wall, the second partition wall, and the at least one lateral electrode defining a side of said parallelepiped respectively.
According to one embodiment, the electrode chamber has a cubic shape.
According to one embodiment, the electrode chamber has a rectangle parallelepiped shape.
According to one embodiment, the electrode chamber has a trapezoidal shape.
It is well understood that the fluidic evacuation or suction from the electrode chamber is realized laterally through the at least one first fluid channel and through the at least one second fluid channel. Thus, the electrostatically actuated device presents reduced fluidic response time.
According to an embodiment, the electrostatically actuated device comprises a plurality of electrode chambers, each of the first partition wall of each electrode chamber of the plurality of electrode chambers comprises at least one first fluid channel configured to allow the passage of a fluid to a unique first chamber, said first chamber being common to the plurality of electrode chambers, and each of the second partition wall of each electrode chamber of the plurality of electrode chambers comprises at least one second fluid channel configured to allow the passage of a fluid to a unique second chamber, said 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 to any other adjacent electrode chamber along one among the at least one lateral electrode.
According to an embodiment, each electrode chamber share at least one lateral electrode with any other adjacent electrode chamber.
The arrangements described above make it possible to propose a compact electrostatically actuated device.
According to one embodiment, said shared lateral electrode comprises a plate substrate comprising two opposite plate surface covered respectively by a thin metallic layer. Thus one unique lateral electrode can act as lateral electrode for two adjacent stacked electrode chambers.
According to this embodiment, the two opposite thin metallic layers are electrically connected by at least one via provided through the plate substrate of the lateral electrode.
According to one embodiment, the two opposite thin metallic layers are electrically isolated from one another.
According to an embodiment, each deformable electrode comprised in each electrode chamber of the plurality of electrode chambers is actuated individually compared to any other deformable electrode.
The arrangements described above make it possible to tune the actuation of the electrostatically actuated device, by actuating more precisely each deformable electrode.
According to an embodiment, the plurality of electrode chambers comprises a first electrode chamber delimiting a primary internal volume and a second electrode chamber delimiting a secondary internal volume, said primary internal volume being strictly different from said secondary internal volume.
In other words, the internal volume of each electrode chamber of the plurality of electrode chambers varies.
Advantageously, the electrostatically actuated device comprises electrode chambers with different internal volumes. Thus, it is possible to actuate independently each electrode chamber to push reversely an adapted volume of fluid.
According to one embodiment, a distance between the first partition wall and the second partition wall of one electrode chamber varies compared to a distance between the first partition wall and the second partition wall of another electrode chamber.
According to one embodiment, a distance between two lateral electrodes of one electrode chamber varies compared to a distance between two lateral electrodes of another electrode chamber.
According to one embodiment, the first electrode compartment delimits a first volume and the second electrode compartment delimits a second volume; the first volume and the second volume are controlled by a capacitance measurement.
Thus, this configuration allows the control of the first volume and/or of the second volume by a capacitance measurement more exactly by measuring the frequency of a relaxation oscillator, which depends on the capacitance for example.
The object of the present disclosure may also be achieved by implementing spectacles comprising an electrostatically actuated device according to one of the embodiments described above.
The foregoing and other purposes, features, aspects and advantages of the present disclosure will become apparent from the following detailed description of embodiments, given by way of illustration and not limitation with reference to the accompanying drawings, in which the same reference refer to similar elements or to elements having similar functions, and in which:
In the figures and in the remainder of the description, the same references represent identical or similar elements. In addition, the various elements are not represented to scale so as to favor the clarity of the figures. Furthermore, the different embodiments and variants are not mutually exclusive and can be combined with one another.
As illustrated on
As shown in
The electrostatically actuated device 1 may also comprises at least one first chamber 10, and at least one second chamber 20 distinct from the at least one first chamber 10. the at least one electrode chamber 50 being disposed between the at least one first chamber 10 and the at least one second chamber 20 so that the at least one electrode chamber 50 is encapsulated between the first chamber 10 and the second chamber 20. Consequently, the at least one first fluid channel 31 is configured to allow the passage of the first fluid 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 the passage of the second fluid between the at least one electrode chamber 50 and the at least one second chamber 20. As illustrated in
The at least one electrode chamber 50 also comprises at least one lateral electrode 3, 5 extending laterally along the direction of extension X.
The at least one electrode chamber 50 may also include a first partition wall 30 defined adjacent to the first chamber 10 and a second partition wall 40 defined adjacent to the second chamber 20. According to the embodiment illustrated on
As illustrated on
According to one embodiment, the electrode chamber 50 present a general shape of a parallelepiped, for example presenting a cubic shape, a rectangle parallelepiped shape, or a trapezoidal shape. Each of the first partition wall 30, the second partition wall 40, the longitudinal walls, and the at least one lateral electrode 3, 5 defining a side of said parallelepiped respectively. The first partition wall 30 and the second partition wall 40 can define two transversal sides of the electrode chamber 50, and two opposite lateral electrodes 3, 5 may define two lateral side of the electrode chamber 50. In the variant represented on
As illustrated on
The at least one electrode chamber 50 is further adapted to receive a deformable electrode 55. According to one embodiment, the deformable electrode 55 is disposed in at least one electrode chamber 50 such as to partition said at least one electrode chamber 50 in a first electrode compartment 57, and a second electrode compartment 59. It is well understood that the first electrode compartment 57 and the second electrode compartment 59 are distinct. Advantageously, the first electrode compartment 57 is fluidly isolated from the second electrode compartment 59. In others words, the first electrode compartment 57 does not fluidly communicate to the second electrode compartment 59. The first electrode compartment 57 is then delimited at least partially by the first partition wall 30, the deformable electrode 55, and the at least one lateral electrode 3, 5. The second electrode compartment 59 is delimited at least partially by the second partition wall 40, the deformable electrode 55, and the at least one lateral electrode 3, 5.
The deformable electrode 55 is configured to cooperate with the at least one lateral electrode 3, 5 such as to be actuated between at least a first position and a second position. By this way, the deformable electrode 55 is able to push reversely a volume of fluid through at least one channel chosen 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 position and the second position. To perform such actuation, the electrostatically actuated device 1 comprises a power supply 2 configured to actuate the deformable electrode 55 and a voltage controller configured to supply an alternative current and/or an alternative voltage from the power supply 2 to the deformable electrode 55. In the particular embodiment illustrated on
The actuation of the deformable electrode 55 to push a volume of fluid is for example implemented according to the embodiments described in EP3507644A1, which is hereby incorporated by reference to the maximum extent allowable by law. The dotted arrows illustrated in
The configurations described above allows having a stronger pumping pressure on the different fluids. It is well understood that the fluidic evacuation or suction from the electrode chamber 50 is realized laterally through the at least one first fluid channel 31 and through the at least one second fluid channel 41. Thus, the electrostatically actuated device 1 presents reduced fluidic response time.
Advantageously, the deformable electrode 55 can comprise a deformable dielectric layer 551 and at least one electroconducting portion 553. Thus, this configuration allows having a displacement of the deformable electrode 55 via an electric field.
As stated before, the lateral electrode 3, 5 may present a roughness inferior to 1 μm or inferior to 50 nm. Thus, using a polished lateral electrode 3, 5 allows both to increase the surface capacitance to improve the actuation efficiency, and to allow broader deformation of the deformable electrode 55 when entering in contact with the lateral electrode 3, 5. It is particularly suitable with micrometric devices when a slight deformation induces a relative large fluidic displacement.
Generally, the at least one lateral electrode 3, 5 comprises an insulating layer 7 configured to electrically insulate at least partially the at least one lateral electrode 3, 5 from the deformable electrode 55. Thus, is possible to avoid direct contact between the deformable electrode 55 and the at least one lateral electrode 3, 5, to suppress any short-cut issue between said deformable electrode 55 and said lateral electrode 3, 5.
The electrostatically actuated device 1 described above make it possible to push reversely fluids contained in the electrode chamber 50 outwardly by actuation of the deformable electrode 55. For example, the electrostatically actuated device 1 may be configured to push a limited volume only. Such electrostatically actuated device 1 may for example be used to control the optical power of fluid lens. The dedicated structure of the at least one electrode chamber 50 with at least one lateral electrode 3, 5 extending laterally to the direction of extension X allows both to have a better control of fluid movements and to simplify the overall structure of the electrode chamber 50. Indeed dissociating the actuating function of the lateral electrode 3, 5 and the fluidic path function of the first fluid channel 31 and the second fluid channel 41 facilitate the electrostatically actuated device 1 manufacturing and assembly.
The small dimension of the overall device make it possible to design a micrometric electrostatically actuated device 1, adapted to be integrated in wearable device. For example, the electrostatically actuated device 1 is adapted to be mounted on microfluidic devices for biological applications, tests, diagnosis, medical devices. Such medical devices include contact lenses, intraocular implants but also non-optical medical devices like small electrostatically actuated devices for drug delivery of small electrostatically actuated devices for biological fluids analysis external as well as implanted in a living body.
According to another embodiment illustrated in
On the particular embodiment illustrated on
Advantageously, each deformable electrode 55a-d comprised in each electrode chamber 50 of the plurality of electrode chambers 50 is actuated individually compared to any other deformable electrode 55. The arrangements described above make it possible to tune the actuation of the electrostatically actuated device 1, by actuating more precisely each deformable electrode 55.
Moreover, when the plurality of electrode chambers 50 comprises a first electrode chamber 50a, and a second electrode chamber 50b, it can be intended that said first electrode chamber 50a delimit a primary internal volume and that the second electrode chamber 50b delimit a secondary internal volume being strictly different from said 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 electrostatically actuated device 1 comprises electrode chambers 50 with different internal volume, it is possible to actuate independently each electrode chamber 50 to push reversely an adapted volume of fluid. In order to tune the internal volume of each electrode chamber 50, a distance between the first partition wall 30 and the second partition wall 40 of one first electrode chamber 50a may vary compared to a distance between the first partition wall 30 and the second partition wall 40 of another electrode chamber 50, for example the second electrode chamber 50b. Simultaneously or not, a distance between two lateral electrodes 3, 5 of one electrode chamber 50 may vary compared to a distance between two lateral electrodes 3, 5 of another electrode chamber 50, to tune the internal volume of each electrode chamber 50.
Number | Date | Country | Kind |
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21199358.9 | Sep 2021 | EP | regional |
This application is a National Stage of PCT Application No. PCT/EP2022/075975 filed on Sep. 19, 2022, which claims priority to EP patent application Ser. No. 21/199,358.9 filed on Sep. 28, 2021, the contents each of which are incorporated herein by reference thereto.
Filing Document | Filing Date | Country | Kind |
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PCT/EP2022/075975 | 9/19/2022 | WO |