INDIVIDUAL PERFORMANCE OPTIMIZATION OF ELECTRONIC LENS FOR PRESBYOPIA CORRECTION

20210240009 · 2021-08-05

    Inventors

    Cpc classification

    International classification

    Abstract

    An optimization system for presbyopia correction includes a dynamic lens and a separately disposed controller. The dynamic lens includes a sensor measuring an ocular element of a person's eye, a control electronics, an actuator, and a presbyopia correcting optical element communicating with the actuator for its setting to a far or near optical power. The controller sends paired instructions synchronically to the person as an audio command for viewing the object at far or near distance and to the control electronics as a wireless command to send the actuation signal to the actuator for communication with the presbyopia correcting optical element. The control electronics receives the wireless command and the sensor signal, stores the sensor signal, sends the actuation signal to the presbyopia correcting optical element and stores the corresponding actuation signal. The actuation signal communicates to the presbyopia correcting optical element to set for far or near optical power.

    Claims

    1. An optimization system for presbyopia correction, comprising: a dynamic lens comprising: i) a sensor configured to measure a difference in an effect of an ocular element of an eye of a person viewing an object between a far distance and a near distance; ii) a control electronics configured to receive a sensor signal from the sensor; iii) an actuator configured to receive an actuation signal from the control electronics; and iv) a presbyopia correcting optical element configured to communicate with the actuator for its setting in one of an optical power for far distance and another optical power for near distance; and a controller associated with and disposed separate from the dynamic lens, wherein the controller is configured to send a paired instruction synchronically to the person as an audio command to view the object at one of the far distance and the near distance and to the control electronics of the dynamic lens as a wireless command to send the actuation signal to the actuator for communication with the presbyopia correcting optical element, wherein the audio command and the wireless command both correspond to the one of the far distance and the near distance; wherein the control electronics is configured to receive the wireless command from the controller and the sensor signal from the sensor, store the sensor signal, send the actuation signal to the presbyopia correcting optical element and store the corresponding actuation signal; wherein the actuation signal for the far distance communicates to the presbyopia correcting optical element of the dynamic lens to set it for the optical power for far distance to bring the object at the far distance in-focus; and wherein the actuation signal for the near distance communicates to the presbyopia correcting optical element of the dynamic lens to set it for the another optical power for near distance to bring the object at near distance in-focus.

    2. The optimization system for presbyopia correction of claim 1, wherein the far distance is defined as 2 meters and beyond, and wherein the near distance is defined as 0.5 meter and closer.

    3. The optimization system for presbyopia correction of claim 2, wherein the paired instruction comprises a plurality of paired instructions relating to one of the far distance or near distance, wherein each audio command of a plurality of audio commands includes a first instruction for the person to view the object at either the far or the near distance and includes a second instruction for the person to change a gaze direction either right, left, up or down.

    4. The optimization system for presbyopia correction of claim 3, wherein the gaze direction is changed by the head tilt of the person either right, left, up or down

    5. The optimization system for presbyopia correction of claim 3, wherein a plurality of wireless commands are associated with the plurality of audio commands, wherein the control electronics is configured to store a matrix of a plurality of sensor signals and actuation signals corresponding to the same far distance or near distance.

    6. The optimization system for presbyopia correction of claim 2, wherein the dynamic lens is an eyewear lens.

    7. The optimization system for presbyopia correction of claim 2, wherein the dynamic lens is an intraocular lens.

    8. The optimization system for presbyopia correction of claim 2, wherein the dynamic lens is a contact lens.

    9. A method of optimization for presbyopia correction, comprising: providing a dynamic lens comprising: i) a sensor configured to measure a difference in an effect of an ocular element of an eye of a person viewing an object between a far distance and a near distance; ii) a control electronics configured to receive a sensor signal from the sensor; iii) an actuator configured to receive an actuation signal from the control electronics; and iv) a presbyopia correcting optical element configured to communicate with the actuator for its setting in one of an optical power for far distance and another optical power for near distance; and providing a controller associated with and disposed separate from the dynamic lens, wherein the controller is configured to send a paired instruction synchronically to the person as an audio command to view the object at one of the far distance and the near distance and to the control electronics of the dynamic lens as a wireless command to send the actuation signal to the actuator for communication with the presbyopia correcting optical element, wherein the audio command and the wireless command both correspond to the one of the far distance and the near distance; wherein the control electronics is configured to receive the wireless command from the controller and the sensor signal from the sensor, store the sensor signal, send the actuation signal to the presbyopia correcting optical element and store the corresponding actuation signal; wherein the actuation signal for the far distance communicates to the presbyopia correcting optical element of the dynamic lens to set it for the optical power for far distance to bring the object at the far distance in-focus; and wherein the actuation signal for the near distance communicates to the presbyopia correcting optical element of the dynamic lens to set it for the another optical power for near distance to bring the object at near distance in-focus. installing the dynamic lens at the eye of the person; sending, via the controller while utilizing the control electronics in an optimization mode, the paired instruction comprising the audio command to the person and the wireless command to the control electronics; storing, via the control electronics, the sensor signal that is associated with the wireless command; and sending the actuator signal to the dynamic lens based on the sensor signal while utilizing the control electronics in an operation mode.

    10. The method of optimization for presbyopia correction of claim 9, wherein the far distance is defined as 2 meters and beyond, and wherein the near distance is defined as 0.5 meter and closer.

    11. The method of optimization for presbyopia correction of claim 10, wherein the paired instruction comprises a plurality of paired instructions relating to one of the far distance or near distance, wherein each audio command of a plurality of audio commands includes a first instruction for the person to view the object at either the far or the near distance and includes a second instruction for the person to change a gaze direction either right, left, up or down.

    12. The method of optimization for presbyopia correction of claim 11, wherein the gaze direction is changed by the head tilt of the person either right, left, up or down

    13. The method of optimization for presbyopia correction of claim 11, wherein a plurality of wireless commands are associated with the plurality of audio commands, wherein the control electronics is configured to store a matrix of a plurality of sensor signals and actuation signals corresponding to the same far distance or near distance.

    14. The method of optimization for presbyopia correction of claim 9, wherein the dynamic lens is an eyewear lens

    15. The method of optimization for presbyopia correction of claim 9, wherein the dynamic lens is an intraocular lens.

    16. The method of optimization for presbyopia correction of claim 9, wherein the dynamic lens is a contact lens.

    Description

    BRIEF DESCRIPTION OF THE DRAWINGS

    [0025] The accompanying drawings illustrate the invention. In such drawings:

    [0026] FIG. 1 shows a block diagram of individual performance optimization method for an electronic dynamic lens that is applied to dynamic Eyewear lens, dynamic IOL and dynamic CL.

    [0027] FIG. 2A through FIG. 2C describe applications of individual performance optimization method to dynamic eyewear lens.

    [0028] FIG. 3 describes application of individual performance optimization method to dynamic IOL.

    [0029] FIG. 4 describes application of individual performance optimization method to dynamic CL.

    [0030] FIG. 5A through 5D demonstrate bi-state piezoelectric actuator operation in providing 2 stable states where the electric energy is consumed only for switching between the states.

    DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

    [0031] FIG. 1 shows a block diagram of individual performance optimization method for an electronic dynamic lens that is applied to dynamic eyewear lens, dynamic IOL and dynamic CL. The corresponding “optimization system” consists of controller 100 and dynamic lens that includes sensor 130, control electronics 140, actuator 150 and presbyopia correcting optical element 160. The controller 100 provides paired synchronized instructions to a wearer 110 as shown by line 1a and control electronics of the dynamic lens as shown by line 1b. Actuator 150 controls presbyopia correcting optical element 160 of the dynamic lens to change its optical power. Sensor 130, control electronics 140, actuator 150 and presbyopia correcting optical element 160 are all part of the dynamic lens.

    [0032] Controller 100 provides audio instruction to a wearer 110 to view an object at certain distance with certain gaze direction. It may also instruct the wearer what object to use for the viewing. Synchronically, the controller 100 wirelessly instructs the control electronics 140 to output actuation signal (electric voltage, for instance) to the actuator 150 as shown by line 5, that takes the presbyopia correcting optical element 160 to an optical power that brings the viewing object in-focus, as shown by line 6. If the controller instructs wearer 110 of the dynamic lens to view the object at far distance, the instruction to the control electronics 140 is to output the “actuation signal for far” for the presbyopia correcting optical element 160 to provide “far optical power” that brings far object in-focus. If the controller instructs wearer 110 of the dynamic lens to view the object at near distance, the instruction to the control electronics 140 is to output the “actuation signal for near” for the presbyopia correcting optical element 160 to provide “near optical power” that brings near object in-focus. If the controller instructs wearer 110 of the dynamic lens to view the object at intermediate distance, the instruction to the control electronics 140 is to output the “actuation signal for intermediate” for the presbyopia correcting optical element 160 to provide “intermediate optical power” that brings intermediate object in-focus.

    [0033] The dynamic lens of the wearer interacts with the corresponding ocular element 120 as shown by line 2. Ocular element is such that the interaction with it varies with the wearer viewing objects at different distances at far and near and change in gaze directions when viewing such objects. An interaction between the dynamic lens and ocular element 120 and a change in interactions are measured by the sensor 130 as shown by line 3. A type of interaction and type of sensor vary for different type of dynamic lens and will be described below. An interaction is converted by the sensor 130 into input electric signal to the control electronics 140 as shown by line 4. The signal shown by line 4 is called the “sensor signal.” Depending upon dynamic lens installation in reference to the eye, anatomy and physiology of the eye, the interaction and sensor signal varies between different wearers.

    [0034] The method used by the optimization system for individual performance optimization is to establish a range of sensor signals of an individual wearer, so called “range of sensor signal” that produces an activation signal that brings a viewing object in-focus for this individual wearer. A range of sensor signal is established for each distance being far, near and, possibly, intermediate, and they are called correspondently “range of sensor signal at far”, “range of sensor signal at near” and “range of sensor signal at intermediate.” Correspondently, the control electronics 140 produces “actuation signal for far”, “actuation signal for near” and “actuation signal for intermediate” that results in correspondent “far optical power”, “near optical power” and “intermediate optical power” by the presbyopia correcting optical element 160. The range of sensor signal is established for a practical range of gaze directions of the wearer when viewing an object at a specified distance. Changes in gaze directions are created by the wearer slightly turning head right, left, up and down when viewing the object at the specified distance, i.e. an object at far distance, an object at near distance or object at intermediate distance. The process involves practical conditions of head positions when viewing an object at each distance. In cases where ranges of sensor signals overlap, the control electronics may provide a wireless feedback to the controller to instruct the wearer on a limit in some gaze directions to provide a robust performance of the dynamic lens, for instance to limit down gaze when viewing far object or limit upper gaze when viewing a near object in case of dynamic eyewear lens or dynamic contact lens.

    [0035] During this “optimization mode,” a “teaching” program of the controller goes over a certain sequence of paired interactions to instruct the wearer on changes in gaze directions for an object at a given distance and a “learning” program of the control electronics stores a matrix that correlates a range of sensor signal and actuation signal for the same distance, i.e. actuation signal for far corresponds to a range of sensor signal at far, actuation signal for near corresponds to a range of sensor signal at near and actuation signal for intermediate corresponds to a range of sensor signal at intermediate. In the operation mode, the dynamic lens operates independently of the controller in the operation mode where the learning program of the control electronics 140 follows a program algorithm to analyze a sensor signal received by the control electronics to provide an actuation signal that brings a viewing object in-focus. Thus, the optimization mode establishes individual performance for presbyopia correction for an unique dynamic lens installation at the wearer eye and unique anatomy and physiology of the wearer of the dynamic lens.

    [0036] FIG. 2A shows an example of optimization system of dynamic eyewear lens. It includes a controller 105 and dynamic eyewear lens 180 framed at the spectacles 155. Dynamic eyewear lens 180 is the right lens of the spectacles 155, left eyewear lens is a mirror image of the right eyewear lens 180 and, therefore, only right dynamic eyewear lens 180 is described. The eyewear lens 180 includes upper presbyopia correcting optical element 190 and lower presbyopia correcting optical element 200. As an example, SBS optical element is used for both elements but they can be any types of dynamic lens being fluidic balloon, Alverez type or electro-active material that changes refractive index under electric filed. SBS optical element 190 switches between far and intermediate optical powers and SBS element 200 switches between far and near optical powers. The dynamic eyewear lens 180 includes infra-red (IR) emitters 250 and 270 and IR sensors 230 and 260. The sensors are connected to the control electronics 215 to provide input signal on eye tracking, i.e. a change in gaze direction. The front surface of the eye is the ocular element for the dynamic eyewear lens, where, as the eye's gaze direction changes an interaction of the ocular element with the sensor 230 and/or 260 changes where interaction is a flux of the IR light measured by the IR sensor upon IR light reflection off the ocular element of the eye. The dynamic eyewear lens 180 also includes actuator 210 for SBS optical element 200 and actuator 220 for SBS optical element 190, both connected to the control electronics 215 to receive its output signal to actuate the corresponding presbyopia correcting optical elements 190 and 200.

    [0037] Paired instructions as shown by line 3a is provided by the controller 105. The wearer audio instruction requires the wearer to look at the far object with straight ahead gaze as indicating by the visual axis 170 of the wearer's right eye 165. The visual axis 170 passes through the SBS optical element 190. At least one of the sensors 230 and 260 or both provide “sensor signal” as input signal to the control electronics 215. The wireless instruction for control electronics 215 commands it to output “activation signal for far” to the actuators 220 and 210 to switch SBS optical elements 190 and 200 to “far optical power.” The corresponding sensor signal is stored by a “learning” program of the control electronics 215. The “teaching” program of the controller 215 sends another paired instructions to require the wearer to view the far object with straight ahead gaze but slightly turning head to the right. The process is repeated and the control electronics 215 stores the corresponding sensor signal. The process is repeated with head turning slightly left, up, down, and the process may be repeated. The set of sensor signals results in a “range of sensor signal at far” together with the “actuation signal for far” form the matrix that is stored by the “learning” program of the control electronics 215. This allows for the wearer's dynamic lens robust operation in viewing an object at far distance because the range of sensor signal at far covers signal values that practically occurs when viewing far object with an eyewear lens. The program of the control electronics 215 runs an algorithm that outputs activation signal for far to both presbyopia correcting optical elements 190 and 200 to provide far optical power to bring the far object in-focus.

    [0038] FIG. 2B shows an example of optimization system including a controller 105 and dynamic eyewear lens 180′ framed at the spectacles 155 where paired instructions are shown by line 3b. The instruction to a wearer is to view a near object with downward gaze as indicating by the visual axis 170′ with downward angle “a” from the visual axis 170 of the wearer's right eye 165. The visual axis 170′ passes through the SBS optical element 200′. At least one of the sensors 230 and 260 or both provide “sensor signal at near” as input signal to the control electronics 215. The wireless instruction to the control electronics 215 instructs it to output “activation signal for near” to actuator 210 to switch SBS optical element 200′ to near optical power. The sensor signal is stored by the control electronics 215. The “teaching” program of the controller 105 sends another paired instruction to require the wearer to view the near object with slightly turning head right, left, up and down. The process may be repeated and the control electronics 215 stores the corresponding “range of sensor signal at near.” The set of sensor signals results in a “range of sensor signal at near” together with the “actuation signal for near” form the matrix that is stored by the “learning” program of the control electronics 215. This is the optimization mode for the electronic dynamic eyewear lens with the controller producing paired instructions of audio command to a wearer and wireless command to control electronics where both reference to the one of the “far” and “near” distances by wearer's viewing and producing optical power. In the operation mode a sensor signal falls within the range of sensor signal at near, the control electronics algorithm operates an algorithm over the matrix to output the actuation signal for near to bring near object in-focus. If the ranges of sensor signal at far and near overlap, the control electronics instructs the controller 105 on the overlap between certain gaze directions and the controller instructs the wearer to limit gaze directions in a corresponding plane, likely head down in far viewing and head up in near viewing.

    [0039] FIG. 2C shows an example of optimization system including a controller 105 and dynamic eyewear lens 180″ framed at the spectacles 155 where a paired instruction as shown by line 3c is provided by the controller 105 for an object at intermediate distance. The instruction to wearer is to view an object at intermediate distance with both eyes. Binocular viewing creates convergence with a gaze direction by the right eye 165 indicated by the visual axis 170″ with its angle of convergence “β” to the visual axis 170. The visual axis 170″ passes through the SBS optical element 190′. At least one of the sensors 230 and 260 or both provide “sensor signal at intermediate” as input signal to the control electronics 215. The wireless instruction to the control electronics 215 commands it to output “activation signal for intermediate” to the actuator 220 to switch SBS optical element 190′ to intermediate optical power. The “teaching” program of the controller 215 send another paired instructions to require the wearer to view intermediate object with slightly turned head to the right and the process is repeated. The process is repeated with head turning slightly left, up, down, and so on. The same as above, a set of sensor signals results in a “range of sensor signal at intermediate” together with the “actuation signal for intermediate” form the matrix that is stored by the “learning” program of the control electronics 215. If the ranges of sensor signal at far and intermediate or intermediate and near overlap, the control electronics instructs the controller 105 on the overlap between certain gaze directions and the controller instructs the wearer to limit gaze directions in a corresponding plane. In the operation mode as a sensor signal falls within the range of sensor signal at intermediate, the control electronics algorithm operates an algorithm over the matrix to output the actuation signal for intermediate to bring the intermediate object in-focus. Same as above, the control electronics communications with the controller on ranges overlap for wearer instruction on the limits in gaze directions for robust dynamic lens performance.

    [0040] FIG. 3 shows an example of optimization system for electronic dynamic IOL. It includes a controller 205 and dynamic IOL 300 supported by the ocular element 310 in the form of ciliary body that includes ciliary muscle. The dynamic IOL 300 is shown with two supporting members 330 and 340 but may include any number of supporting members. Supporting member 330 includes pressure sensor 350 at its very periphery, supporting member 340 includes pressure sensor 360 at its very periphery, both to measure pressure produced by the ciliary body/ciliary muscle 310 in contraction for accommodation in viewing an object at near distance and relaxation for disaccommodation in viewing an object at far distance. Another option is to include bending sensors 390 and 400 to detect supporting members bending with ciliary muscle contraction and relaxation. Pressure sensors and/or bend sensors might be self-powered sensors based on piezoelectric or triboelectric nanogenerator as the present days nanogenerator may produce a voltage of 1.63 V and a power of 0.03 μW. The sensor signal from the sensors is the input to the control electronics placed at the electronics compartment 370. Power and power electronics may be in the same compartment 370. An actuation signal is the output of the control electronics to the actuator, for instance, a piezo-electric bi-state actuator placed at the actuator compartment 380. The dynamic IOL optical body 320 includes presbyopia correcting optical element 410. As an example, SBS optical element is used for switching between far and near optical powers but other types of design such as material based switching using electro-active materials, fluidic balloon design or Alvarez type design can be used.

    [0041] The controller 205 provides paired instructions as shown by line 3′, one is audio instruction for the wearer and another wirelessly to the control electronics of the dynamic lens 300. The following description is provided using SBS optical element as an example of presbyopia correcting optical element. The wearer's audio instruction requires the wearer to view either far or near object. The ocular element interacts with a sensor or sensors to provide correspondently “sensor signal at far” or “sensor signal at near” as input signal to the control electronics. The wireless instruction by the controller 205 to the control electronics commands it to output correspondently “activation signal for far” or “activation signal for near” to the actuator to switch SBS optical element 410 to the corresponding “far optical power” to bring the object at far distance in-focus or “near optical power” to bring the object at near distance in-focus. The “teaching” program of the controller 205 follows a certain algorithm to change gaze directions by instructing the wearer to turn their head slightly when viewing the object at far distance and the object at near distance. Correspondently, the “learning” program of the control electronics collects “range of sensor signal at far” and “range of sensor signal at near” to form a matrix to gather with the corresponding “activation signal for far” and “activation signal for near.” This is the optimization mode for the electronic dynamic IOL with the controller producing paired instructions of audio command to a wearer and wireless command to control electronics where both reference to the one of the “far” and “near” distances by wearer's viewing and producing optical power. The control electronics then operates the matrix under an algorithm to place a sensor signal at an appropriate range of sensor signal and output the appropriate actuation signal for the presbyopia correcting optical element to produce appropriate optical power that brings a viewing object in-focus for the given wearer. This is equivalent to the optimization mode and operation by the dynamic eyewear lens of FIG. 2A-2C and described below dynamic contact lens of FIG. 4.

    [0042] If a sensor signal has a resolution to measure interaction with ocular element at intermediate viewing from near and far viewing, and a presbyopia correcting optical element has a capability for intermediate optical power in addition to far and near, the optimization mode runs the paired instructions for intermediate viewing and producing intermediate optical power. Then the “learning” program of the control electronics will store a matrix for intermediate that correlates “range of sensor signal at intermediate” and “actuation signal for intermediate” to be used in operation by the dynamic IOL. The same is applicable to a dynamic eyewear lens of FIG. 2A-2C and dynamic CL of FIG. 4.

    [0043] The FIG. 4 shows an example of optimization system for electronics dynamic CL. It includes a controller 205′ and dynamic CL 420. The dynamic CL 420 consists of optical element 440 of about 7 mm diameter and supporting member 430 which includes prism ballast 450 with truncation in combination with others features of the supporting member 430 such as thin zones (also known as double slab-off) and so on. The ballast 450 is for effective interaction with the lower eyelid 460 which is the ocular element of the dynamic CL 420. The ballast 450 is also for maintaining dynamic CL orientations on the eye. The ballast is commonly used in translating (alternating) contact lenses. The overall sizing is like the one used in segmented and progressive CL designs to insure lens good centration and minimum displacement. Optical element 440 includes presbyopia correcting optical element 490. As an example, SBS optical element is used where SBS optical element 490 switches between far and near optical powers. The presbyopia correcting optical elements can be also of other designs such as material based switching using electro-active materials, fluidic balloon design or Alvarez type design. The ballast 450 includes control electronics 470 connected with a pressure sensor 510 at the lower edge of the ballast to measure a pressure exerted by the ocular element 460 on the ballast. The ballast 450 also includes actuator 480 for to actuate a presbyopia correcting optical element to different optical powers, in this case the SBS optical element 490 via a channel 500. The actuator 480 may be piezoelectrical bi-state actuator described below. In case of material-based switching by electro-active material, electric wiring connects the electronics actuator connected to the control electronics and presbyopia correcting optical element.

    [0044] The controller 205′ provides paired instructions as shown by line 3″, one is audio instruction for the wearer and another wirelessly to the control electronics 470. The wearer's audio instruction requires the wearer to view an object at near distance with downward gaze and an object at far distance with straight ahead gaze. The pressure sensor 510 provides “sensor signal at far” or “sensor signal at near” as input signal to the control electronics 470 at different gaze directions. The wireless instruction for control electronics 480 instructs to output actuation signal to the actuator 220 for switch SBS optical element 490 to far optical power when the wearer is instructed to view the object at far distance and near optical power when the wearer is instructed to view an object at near distance. A sensor signal is stored at each viewing by the control electronics 270. The “teaching” program of the controller 205′ sends a set of paired instructions per certain algorithm to instruct the wearer to view the object at far distance with slightly turning head to the right, left, up and down to create different gaze directions at far object viewing. The control electronics 470 stores different sensor signals to form a “range of sensor signal at far.” At each gaze direction at far distance viewing, the controller 205′ instructs the control electronics 470 to output “actuation signal for far.” The result is that the control electronics 470 stores the matrix of the range of sensor signal at far and actuation signal for far. The process is repeated for an object at near distance resulting in a matrix for viewing an object at near distance with the result the matrix of the range of sensor signal at near and actuation signal for near. In the operation mode the control electronics 470 then operates the matrix under an algorithm to place a sensor signal at an appropriate range of sensor signal and output the appropriate actuation signal for the presbyopia correcting optical element to produce appropriate optical power that brings a viewing object in-focus for the given wearer.

    [0045] FIG. 5A though FIG. 5D show piezoelectric bi-stable (bi-state) actuators that switch between two stable states. Piezoelectric actuation is an attractive option for an electronic fluidic dynamic lens due to small dimensions of piezoelectric actuator which allows its placement within the lens together with thin film rechargeable batteries and/or efficient small solar cells and compact microelectronics. The advantage of a bi-state actuation is that no electric energy is consumed in maintaining the actuator in either stable state, the electric energy is consumed only for switching between the stable states. This allows the invention to minimize electric energy used in operating a dynamic lens. The preferred embodiment of the present invention is to use a piezoelectric bi-stable actuator of bimorph (generally, a multimorph) construction in cantilever action where piezoelectric bender in its unbent state is a beam or plate anchored at one end and demonstrate deflection of the other end with electrical field application. A bimorph bender includes two piezoelectric layers to allow bender bending in opposite directions under a voltage of opposite signs, such bender is also called bidirectional bender. In general, stable unbent bender state may be a curved shape.

    [0046] FIG. 5A manifests a bi-state actuator in one the stable states, say State A, where the piezoelectric bender plate 510 is in the corresponding State A. The bender is attached to a flexible anchor 550 of width W at one end, also called a flexible cantilever clamp, which offers a flexible bender clamping. This bender end is called “clamped end” and the other end that moves with a voltage application is called the “deflection end.” The permanent magnets 1, numbered 580 and 2 numbered 570 are spaced by the distance T at distance L from the flexible anchor 550. They can be made of highly magnetically effective Nd 58 material, for instance. The bender 510 in State A is in an unbend shape as the voltage is not applied to the bender in the stable state. The deflection end of the bender 510 includes magneto-active material 560 that is attracted by the permanent magnets, magnet 580 in the State A. Limiting members 590 and 600 support elements 570 and 580 correspondently and they also control a deflection of the deflection end of the bender 590 when a voltage is applied and the bender 510 bends.

    [0047] FIG. 5B demonstrates the bender 510 bending with applied voltage. The limiting member 590 limits a bender's bending down towards the plane of the magnet 580 thus assisting for maximum deflection of the deflection end to reach the magnet 570. The distance T matches the bender deflection magnitude. Upon bending, the deflection end of the bender 510 overcomes the attraction (pulling) force of the magnet 580 and reaches the magnet 570 thus creating a dominant attraction of the deflection end to the magnet 570. As an example, for the bender of length L≈4.5 mm, width W≈2.3 mm and bender thickness of about 0.35 mm, a deflection value is at least 8 microns and force, so called blocking force, is ≈20 grams of force for the applied voltage of 30 V. Regarding a permanent magnet made of Nd 58 material with length 1 mm, width 1.8 mm and thickness 0.2 mm, the pulling force is 15 grams of force. In this example, the blocking force of the bender 20 grams of force exceeds the pulling force of the magnet of 15 grams of force thus allowing the deflection end to reach the opposite magnet and deliver the other stable state. If one must have a different deflection magnitude, say, bender thickness doubles and length is 12 mm, the deflection becomes 100 microns and blocking force ≈55 grams of force. Then the magnet dimensions are also adjusted. Thus, by adjusting bender and magnet dimensions, one can meet the requirements for the bender's deflection magnitude and to overcome a magnet pulling force upon bender bending.

    [0048] FIG. 5C demonstrates the unbent bender 510 upon voltage termination with the deflection end at the magnet 570. The bender takes its normal unbent shape of State B with a different angular position between the magnet 570 and flexible anchor 550. This is because the bender's clamping end is in the flexible anchor 550. If an actuator chamber (not shown) is attached to the bender 510, the difference in bender position between States A and B creates a difference in actuation chamber volume and allow to move the fluid between the actuation chamber and connected to it presbyopia correcting optical element. For instance, an actuator with dimensions of length L≈6.5 mm, width W≈3.5 mm and thickness T 1.5 mm would produce a deflection Def≈25 microns. This, in turn, transfers a fraction of microliter of the optical fluid between the actuation chamber and presbyopia correcting optical element. Such volume is adequate for SBS optical element switching in case of dynamic IOL and dynamic CL applications.

    [0049] FIG. 5D demonstrates the bender 510 bending with applied voltage in the opposite direction from the one in the FIG. 5B. The limiting member 600 limits a bender's bending up towards the plane of the magnet 570 to allow maximize a deflection of the deflection end to reach the magnet 580. The deflection end of the bender 510 overcomes the attraction (pulling) force of the magnet 570 and reaches the magnet 580 thus creating a dominant attraction of the deflection end to the magnet 580. Upon the voltage termination, the bender 510 takes a normal unbent shape of the State A as shown on the FIG. 5A as the clamping end of the bender is at the flexible anchor 550 to allow for different angles of the bender plate.

    [0050] It might be possible to introduce a transparent visual spectrum piezoelectric for the actuator with Lithium niobate (LNO) material or thin layers of MoS.sub.2, for instance. Transparency would make the dynamic lens more cosmetically appealing and increase flexibility in choosing bender design dimensions.