Shape changing optical device for ophthalmic test device

Abstract

The invention relates to an optical device, in particular for an ophthalmic device, comprising: a container enclosing an interior space of the container, where the interior space is filled with a transparent liquid, and where the container comprises a transparent bottom and a transparent and elastically deformable membrane opposite the bottom, such that the liquid is disposed between the membrane and the bottom; a deformable annular lens-forming element connected to the membrane such that a circumferential edge of the lens-forming element defines a central region of the membrane such that light can pass through the container via the central region and the bottom, where, in a non-deformed state, the lens-forming element is configured to form a deformable annular lens-forming element, the deformable annular lens-forming element is configured to form a deformable annular lens-forming element, and the deformable annular lens-forming element is configured to form a deformable annular lens-forming element. The edge is positioned in a plane; and an adjustable degree of sphericity and an adjustable degree of cylindricity wherein, in order to accommodate the degree of cylindricity of the optical device, the lens shaping element is configured to be bent out of the plane.

Description

[0001] This application is a divisional application of an invention patent application with an application date of December 16, 2019, application number "201980082686.4", and invention name "Shape-changing optical device for ophthalmic testing device". Technical Field

[0002] The present invention relates to an optical device, in particular for use in ophthalmic devices. Background Art

[0003] Ophthalmic testing equipment usually has to meet certain requirements specified in the corresponding standards. In particular, according to ISO10341:2012(E), the sphere, cylinder and prismatic power as well as the corresponding axes need to be adjustable.

[0004] In particular, the minimum measuring range of the sphericity of the refractory head should be: from 0D to +15D in steps of 0.25D, and from 0D to -15D in steps of 0.25D.

[0005] In addition, the minimum measurement range of cylindrical (or astigmatism) power should be: from 0D to 5D in positive or negative cylinder form, with a step size of 0.25D, and the minimum measurement range of prismatic power should be: from 0Δ to 10Δ in steps of 1Δ or continuously.

[0006] Additional requirements relate to the free aperture and the pupil distance.

[0007] In addition, it is known in the prior art that fluid lenses can be used to produce astigmatism and defocus wavefront correction via Zernike modes (i.e., Appl Opt. 2009; 48(19): 3580-7, see also: Lin Pang, Uriel Levy, Kyle Campbell, Alex Groisman, and Yeshaiahu Fainman, "Set of two orthogonal adaptive cylindrical lenses in a monolith elastomer device", Opt. Express 13, 9003-9013 (2005); Randall Marks, David L. Mathine, Gholam Peyman, Jim Schwiegerling, and Nasser Peyghambarian, "Adjustable fluidic lenses for ophthalmic corrections", Opt. Lett. 34, 515-517 (2009); Randall Marks, David L. Mathine, Gholam Peyman, Jim Schwiegerling, and N. Peyghambarian, “Adjustable adaptive compact fluidic phoropter with no mechanical translation of lenses,” Opt. Lett. 35, 739-741 (2010). Summary of the invention

[0008] Based on the above, the object of the present invention is to provide an optical device which can be used in particular for ophthalmic testing devices and which comprises a relatively small installation space and allows integration of adjustable spherical and cylindrical powers (and in particular also prismatic powers) in a single optical element.

[0009] This problem is solved by an optical device according to an embodiment of the present invention.

[0010] Preferred embodiments of these aspects of the invention are set out in the other embodiments of the invention and are also described below.

[0011] According to an embodiment of the present invention, an optical device, in particular for an ophthalmic device, is disclosed, comprising:

[0012] - a container enclosing an interior space of the container, wherein the interior space is filled with a transparent liquid, and wherein the container comprises a transparent bottom and a transparent and elastically deformable membrane opposite the bottom, such that the liquid is arranged between the membrane and the bottom,

[0013] a deformable annular lens-forming element connected to the membrane such that a circumferential (e.g. circular) edge of the lens-forming element defines a central region of the membrane such that light can pass through the container via the central region and the bottom, wherein in a non-deformed state said edge of the lens-forming element defines a plane (i.e. a flat virtual surface),

[0014] - and wherein the optical device comprises an adjustable sphericity and an adjustable cylinder, wherein, in order to adapt the cylinder of the optical device, the lens-forming element is configured to be curved out of said plane, in particular such that an edge lies on a curved surface.

[0015] In particular, according to an embodiment, the deformable lens forming element may be an elastically deformable lens forming element (eg for providing a restoring force).

[0016] According to an embodiment, in order to adapt the cylinder of the optical device, the lens forming element is configured to be bent out of said plane such that said edge of the lens forming element coincides with the cylindrical surface.

[0017] In particular, the edge of the lens forming element defines a contact line at which the central region of the membrane protrudes from the lens forming element. Thus, in case of an axial movement of the lens forming element (i.e. along the optical axis), the spherical power of the optical device changes, since the movement changes the spherical component of the curvature of said region of the lens. Furthermore, in case of a bending of the lens forming element out of said plane, the region of the membrane forms a cylindrical curvature and a corresponding cylindrical power.

[0018] According to an embodiment of the invention, the optical device further comprises an adjustable prismatic power. Furthermore, in order to adjust the prismatic power, the lens-forming element is configured to be tilted relative to the optical axis of the optical device. Due to this tilting, the prismatic power of the optical device is adjusted, since the container can, for example, be formed in a prism (for example starting from a flat state).

[0019] According to an embodiment of the invention, the bottom is connected to the circumferential side wall of the container.In particular, the bottom may be formed as a flat transparent plate (eg made of glass or polymer).

[0020] Furthermore, according to an embodiment of the present invention, the side wall is integrally formed with the bottom. In particular, the side wall and the bottom may be formed by a plate member including a recessed portion for forming the inner space of the container or a portion of the inner space.

[0021] Furthermore, according to one embodiment of the invention, the side wall and the bottom are separate elements connected to each other (eg glued to each other).

[0022] Furthermore, according to an embodiment of the invention, the membrane is connected to (eg glued to) the side walls.

[0023] Furthermore, according to an embodiment of the invention, the container comprises a separate circumferential and flexible sealing element connecting the lens forming element to the side wall or the bottom.

[0024] Furthermore, according to an embodiment of the invention, the bottom forms an elastically deformable further membrane, and wherein the optical device comprises an annular further lens-forming element connected to the further membrane such that a circumferential (e.g. circular) edge of the further lens-forming element defines a central region of the further membrane such that light can pass through the container through said central region of the opposite membrane. In particular, the side wall can form an annular further lens-forming element.

[0025] In addition, according to an embodiment of the present invention, the additional lens forming element is a deformable additional lens forming element, wherein, in a non-deformed state, the edge of the additional lens forming element defines an additional plane, wherein, in order to adjust the cylindrical degree of the optical device, the additional lens forming element is also constructed to be bent outside the additional plane, in particular so that the edge of the additional lens forming element is located on the curved surface and / or coincides with the cylindrical surface.

[0026] Furthermore, according to an embodiment of the invention, the further lens forming element is rigid (in particular compared to the deformable lens forming element).

[0027] Furthermore, according to an embodiment of the present invention, the membrane forms a shell, i.e. it can be elastically bent out of its extension plane and generates a restoring force which tries to bend the shell back to its initial flat state. In particular, in the framework of the present invention, an elastically deformable membrane is considered to be a shell if its dimensionless tension parameter k is less than 5. The dimensionless tension parameter k is defined as:

[0028]

[0029] Where N0 is the initial radial tensile load in the plane, a is the radius of the circular membrane or shell, and D is the bending stiffness. It is defined as:

[0030]

[0031] Where E is the elastic modulus, h is the thickness of the membrane or shell, and ν is Poisson's ratio (see Sheploak, M., & Dugundji, J. (1998). Large deflections of clamped circular plates under initial tension and transitions to membrane behavior. Journal of Applied Mechanics, 65(1), 107-115).

[0032] According to a further embodiment of the optical device according to the invention, the optical device comprises a transparent optical element, which is arranged between the membrane and the bottom, so that the inner space of the container is divided into two separate zones, wherein each zone is filled with a liquid, and wherein the optical device comprises a flexible first side wall (e.g. a bellows) and a flexible second side wall (e.g. a bellows), wherein the first side wall connects the lens forming element to the optical element, and wherein the second side wall connects the optical element to the bottom. This allows the bottom to be tilted and / or moved by a separate actuator to adjust the prismatic power and / or spherical power.

[0033] Furthermore, in accordance with an embodiment of the present invention, the optical device includes an actuator system configured to bend the deformable lens forming element out of plane in order to accommodate the cylinder.

[0034] Furthermore, in accordance with an embodiment of the present invention, the actuator system is configured to displace multiple points of the lens forming element along the optical axis of the optical device to bend the deformable lens forming element out of plane to accommodate cylinder power.

[0035] Furthermore, according to an embodiment of the present invention, the points are arranged along the periphery of the lens forming element. In particular, the points are arranged on a surface of the lens forming element, wherein the surface faces away from the membrane. In particular, the points can be arranged on a centerline of the surface of the lens forming element.

[0036] Furthermore, according to an embodiment of the present invention, the plurality of points comprises at least five points, in particular six points. In particular, according to an embodiment, the plurality of points may be formed by exactly six points.

[0037] Furthermore, according to an embodiment of the invention, the points are equally spaced along the periphery of the lens forming element.

[0038] Furthermore, in accordance with an embodiment of the present invention, the actuator system is configured to displace the points along the longitudinal axis by the same amount to adjust the sphericity of the optical device.

[0039] Furthermore, according to an embodiment of the present invention, the actuator system includes a pump configured to pump the liquid into the inner space or out of the inner space to adjust the sphericity of the optical device.

[0040] Furthermore, according to an embodiment of the invention, the actuator system is configured to displace a point of the lens forming element such that the lens forming element is tilted relative to the optical axis of the optical device to adjust the prismatic power of the optical device.

[0041] Furthermore, according to an embodiment of the present invention, the actuator system is configured to tilt the lens forming elements relative to each other in order to adjust the prismatic power of the optical device.

[0042] In particular, according to a preferred embodiment of the present invention, the actuator system comprises a plurality of actuators, wherein each actuator is configured to displace one of the points.

[0043] In particular, in an embodiment, each actuator comprises a mover that can be moved back and forth along the optical axis of the optical device by the actuator, wherein each mover is coupled to an associated point of the lens forming element (in particular via a compliant coupling element). In an embodiment, the respective actuator may be a linear push-pull actuator.

[0044] Furthermore, according to a further embodiment, each actuator comprises a mover which can be moved by means of the actuator along the optical axis of the optical device towards the lens forming element, wherein each mover is configured to push against an associated point of the lens forming element (in particular via a point contact), and wherein each actuator comprises a spring element which is configured to exert a restoring force on the associated point of the lens forming element. Alternatively (or additionally), the respective actuator can also pull the respective point of the lens forming element.

[0045] Furthermore, according to an embodiment, the respective mover is formed by or comprises a permanent magnet and wherein the respective actuator comprises an electromagnet for moving the permanent magnet (mover) of the respective actuator.

[0046] According to an embodiment, the respective spring element is supported on the bottom. Alternatively, the respective spring element can be supported on the side wall.

[0047] Furthermore, depending on the embodiment, the respective spring element can be, for example, a helical spring or a leaf spring (other spring elements are also possible).

[0048] Furthermore, in an embodiment, the respective spring element is arranged in the inner space and immersed in the transparent liquid.

[0049] Alternatively, the respective spring element may be arranged outside the inner space of the container. In the latter case, according to an embodiment of the present invention, the respective spring element may be formed integrally with the lens forming element.

[0050] Furthermore, according to embodiments, instead of multiple actuators for applying forces at multiple points of the lens forming element, the actuator system may include a bending actuator (such as an isomorphous actuator or a bimorph actuator). In particular, in embodiments, the bending actuator includes at least one first annular active layer, wherein the first active layer is included by the lens forming element (or even forms the lens forming element), and wherein the first active layer is configured to (e.g. anisotropically) expand or contract in a first direction to bend the lens forming element out of the plane, so that the optical device includes a cylinder relative to a cylindrical reference axis.

[0051] Furthermore, the bending actuator may comprise a second active layer, which is comprised by the lens-forming element and is configured to expand or contract (e.g. anisotropically) in a second direction (the second direction may be orthogonal to the first direction) to bend the lens-forming element out of the plane, such that the optical device comprises a cylinder relative to a cylindrical reference axis. In particular, the second active layer may be connected to the first active layer. Alternatively, the second direction may also be colinear with the first direction, wherein, here, when the first active layer expands, the second active layer preferably contracts and vice versa.

[0052] Furthermore, the bending actuator may comprise a passive layer, which is comprised by the lens forming element, wherein the passive layer may be connected to the first active layer (i.e. the bending actuator comprises an active layer and a passive layer), or wherein the passive layer is arranged between the first active layer and the second active layer and is connected to these active layers. Here, the bending actuator comprises three layers, i.e. the passive layer arranged between the first active layer and the second active layer.

[0053] In particular, the passive layer may include or be formed from one of the following materials: steel, stainless steel, aluminum, alloys including copper, brass, polymers, PET, PMMA, fiber-reinforced materials, carbon fiber-reinforced polymers or other suitable materials.

[0054] In addition, in particular, the first active layer and / or the second active layer includes one of the following materials or is formed of one of the following materials: piezoelectric material, (Pb(Zr,Ti)O3(PZT), Pb(Zn1 / 3Nb2 / 3)O3-PbTiO3(PZN-PT)

[0055] In particular, the use of a single bending (e.g. bimorph) actuator may only allow adjustment of the cylinder of a given cylindrical reference axis. To be able to adjust the orientation of the cylindrical reference axis, two such deformable lens forming elements may be used, whose cylindrical reference axes are rotated 45° relative to each other.

[0056] Therefore, according to a further embodiment, the actuator system comprises a further bending actuator, which can be designed as the above-mentioned bending actuator to generate a cylinder relative to a further cylinder reference axis, wherein the further cylinder axis is preferably rotated by about 45° relative to the cylinder reference axis of the further bending actuator (see above).

[0057] In case the respective active layer of the respective bending actuator is a piezoelectric material, the active layer is deformed (e.g. expanded or contracted) by applying an electric field across the piezoelectric material (e.g. by means of a voltage difference between electrodes contacting the material).

[0058] Furthermore, according to an alternative embodiment, the actuator system comprises an actuator comprising at least one first annular active layer, wherein the first active layer is comprised by a lens-forming element (or forms a lens-forming element), wherein the first active layer comprises segments arranged side by side in a circumferential direction of the active layer, the segments being configured to be selectively activated to contract or expand (e.g., isotropically or anisotropically). Also here, the bending actuator may comprise a second active layer connected to the first active layer (e.g., configured similarly to the first active layer) or a passive layer connected to the first active layer. Furthermore, the active layer may comprise a passive layer arranged between the first active layer and the second active layer (see also above).

[0059] In particular, the first (or second) active layer may include twelve segments, wherein the length of each segment in the circumferential direction corresponds to a central angle of the annular active layer of 30°.

[0060] In particular, the passive layer of the bending actuator may include or may be formed from one of the materials described above with respect to the passive layer.

[0061] In particular, a section of the first (or second) active layer of the bending actuator may comprise one of the materials or may be formed of one of the materials mentioned above with respect to the active layer.

[0062] Furthermore, the respective segments can be deformed (expanded or contracted) by applying an electric field across the respective segments / piezoelectric material (eg, by means of a voltage difference between electrodes contacting the respective segments).

[0063] Furthermore, according to an embodiment, the lens forming element is elastically mounted to a holding structure of the optical device.

[0064] In particular, in an embodiment, the actuator system is configured to tilt the base relative to the lens forming element to adjust the prismatic power of the optical device.

[0065] Furthermore, in an embodiment, the actuator system is configured to move the base relative to the lens forming element along an optical axis of the optical device to adjust the sphericity of the optical device.

[0066] With respect to the above-described embodiments, certain actuators that may be used to adjust the cylinder and / or sphericity and / or prismatic power of an optical device have been described.

[0067] However, other actuators allowing a point of the lens-forming element to be displaced or allowing a tilting or axial movement of the lens-forming element or of another element of the optical device, such as the base, can also be used within the framework of the invention.

[0068] In particular, the actuator system may include one of the following actuators (eg for adjusting the cylinder and / or sphericity and / or prismatic power of the optical device):

[0069] - electromagnets that attract or repel permanent magnets (see also above),

[0070] - magnetic resistance actuator,

[0071] - Voice coil actuator,

[0072] - Rotary actuators (e.g. DC, brushless DC, stepper, ultrasonic motors, etc.), in particular including mechanical transmission devices that convert rotary motion into linear motion (e.g. screw, ball screw, cam, worm gear, slider crank mechanism, etc.),

[0073] - a piezoelectric stack (optionally with a stroke amplification mechanism),

[0074] - flexural piezoelectric (see also above),

[0075] -Linear Ultrasonic Motor,

[0076] - Shape memory alloy actuators,

[0077] - thermal expansion actuators, and

[0078] -Hydraulic actuation system.

[0079] Furthermore, the optical device may include a control unit according to an embodiment, which is configured to control an actuator system of the optical device in order to adjust the cylinder and / or spherical power and / or prismatic power of the optical device to desired values, respectively.

[0080] In particular, for carrying out said adjustment, the control unit is configured to use a feedback signal. In particular, the actuator system itself can be configured to provide this feedback signal. In particular, the feedback signal can indicate the position of the corresponding actuator (e.g. a servo actuator). Alternatively or additionally, the optical device can include at least one sensor, which is configured to provide a feedback signal, which indicates the state (in particular the shape and / or curvature) of the lens forming element (and / or the further lens forming element), so that the lens forming element (and / or the further lens forming element) can be bent, for example, in such a way that the optical device includes a desired cylindrical surface.

[0081] According to a further aspect of the present invention, an optical device is disclosed, in particular for an ophthalmic device, the optical device comprising:

[0082] - a container enclosing an interior space of the container, wherein the interior space is filled with a transparent liquid, and wherein the container comprises a transparent bottom and a transparent and elastically deformable membrane opposite the bottom, such that the liquid is arranged between the membrane and the bottom,

[0083] a deformable annular lens-forming element connected to the membrane such that a peripheral edge of the lens-forming element defines a central region of the membrane such that light can pass through the container via the central region and the bottom, wherein in a non-deformed state the edge lies in a plane, and

[0084] - Adjustable sphericity and adjustable cylinder, wherein, in order to adapt the cylinder of the optical device, the lens-forming element is constructed to be deformed so that the shape of the edge is adjustable (for example between circular and elliptical) but still lies in the plane.

[0085] Here, the spherical power and / or prismatic power can be adjusted by moving (spherical power) and tilting (prismatic power) the base relative to the lens-forming element. BRIEF DESCRIPTION OF THE DRAWINGS

[0086] In the following, further advantages, features and embodiments of the present invention are described with reference to the accompanying drawings, in which:

[0087] Figure 1 shows a schematic cross-sectional view of an embodiment of an optical device according to the present invention;

[0088] Figure 2 A lens-forming element of an optical device of the present invention is shown in a state in which the lens-forming element is bent out of its extension plane to adjust the cylinder of the optical device;

[0089] Figure 3 In the absence of a pressure difference across the membrane of the optical device, the shape is very similar to Z1-1 Zernike function. To achieve a pure cylindrical shape (zero degrees on the reference axis), a spherical component can be generated by increasing / decreasing the pressure in the container of the optical device, where Figure 3 Shows Δp>0;

[0090] Figure 4 A further possibility for adjusting the cylinder is shown;

[0091] Figure 5 A schematic cross-sectional view of a further embodiment of an optical device according to the invention is shown, wherein here the container comprises an inlet for pumping liquid into and out of the interior space of the container of the optical device.

[0092] Figure 6 Shows Figure 1 Schematic sectional view of a variant of the embodiment shown, wherein here the side wall and the bottom of the container are formed by separate elements which are connected to one another.

[0093] Figure 7 Shows Figure 6 Schematic cross-sectional view of a variant of the embodiment shown, wherein here the membrane is connected to the side wall in order to omit a separate sealing element connecting the lens forming element to the side wall of the container.

[0094] Figure 8 shows a schematic cross-sectional view of a further embodiment of an optical device according to the invention, wherein here the container comprises two opposing membranes, a deformable lens-forming element and a rigid lens-forming element;

[0095] Fig. 9 Shows Figure 8 A variation of the embodiment shown, in which here the membrane connected to the deformable lens-forming element is formed as a shell.

[0096] Fig.10 It is shown that the cylinder of an optical device can be adjusted by acting on a limited number of points of a lens-forming element with a limited number of actuators, here six points and corresponding actuators;

[0097] Fig.11 A schematic cross-sectional view of an embodiment of an optical device according to the invention is shown, the optical device comprising a plurality of actuators comprised by an actuator system, wherein each actuator is configured to act in a push-pull manner on an associated point of a lens forming element.

[0098] Fig.12 Shows Fig.11Schematic cross-sectional view of a variant of the embodiment shown, wherein here the respective actuator is configured to push against the associated lens-forming element point, while a restoring force is provided by a spring element (e.g. a helical spring) arranged in the interior space of the container;

[0099] Fig.13 Shows Fig.12 A variation of the embodiment shown, wherein here a leaf spring is used instead of a helical spring. In particular, (A) shows a schematic top view indicating the positions of various points, and (B) shows a schematic cross-sectional view of the optical device.

[0100] Fig.14 Shows Fig.13 A variation of the embodiment shown, in which here the leaf spring is arranged outside the interior space of the container of the optical device. Here too, (A) shows a schematic top view of the device, while (B) shows a schematic cross-sectional view;

[0101] Fig.15 A further embodiment of an actuator for bending a lens forming element out of plane is shown, wherein the actuator is a bending actuator;

[0102] Fig.16 Shows Fig.15 Perspective top view of a bending actuator.

[0103] Fig.17 Shows Fig.15 a perspective bottom view of a bending actuator;

[0104] Fig.18 shows how to adjust the cylinder of multiple cylindrical reference axes using two opposing bending actuators;

[0105] Fig.19 Additional bend actuators for bending a lens forming element out of plane about a different cylindrical reference axis are shown, wherein the bend actuators include adjacent segments of an active layer that can expand / contract (e.g., isotropically);

[0106] Fig. 20 Shows the use of Fig.19 The actuator shown bends the lens forming element into an out-of-plane condition.

[0107] Fig.21 Shows the use of Fig.19 The actuator shown bends the lens forming element to an alternative out-of-plane state (with a different cylindrical reference axis).

[0108] Fig. 22 An embodiment of an optical device according to the invention is shown, which comprises for example Fig. 20The actuator as shown, wherein the lens forming element / actuator is resiliently coupled to the retaining structure, and wherein the bottom of the container is configured to tilt or move axially relative to the lens forming element to adjust the spherical power and prismatic power; and

[0109] Fig.23 A further embodiment of an optical device according to the invention is shown which allows bending of the lens-forming element to adjust the cylinder power and tilting of the bottom of the container to adjust the prismatic power. DETAILED DESCRIPTION

[0110] Figure 1 An embodiment of an optical device 1 according to the present invention suitable for an ophthalmic (testing) device is shown. In particular, the optical device 1 comprises a container 2, which encloses an inner space 3 of the container 2, which is filled with a transparent liquid L. The container 2 also comprises a transparent bottom 21 and a transparent and elastically deformable membrane 22 opposite to the bottom 21, so that the liquid L is arranged between the membrane 22 and the bottom 21.

[0111] Furthermore, the optical device 1 comprises a deformable annular lens-forming element 4, which is connected to the membrane 22, such that a peripheral edge 41 of the lens-forming element 4 defines a central region 23 of the membrane 22, such that light can pass through the container 2 via the central region 23 and the bottom 21, wherein, in a non-deformed state, the lens-forming element 4 defines a (virtual) plane, and wherein the optical device 1 comprises an adjustable spherical power, an adjustable prismatic power and an adjustable cylindrical power, wherein, in order to adapt the cylindrical power of the optical device 1, the lens-forming element 4 is constructed to be bent to said plane P (see Figure 2 ) in addition to the above, the lens forming element 4 defines a (virtual) cylindrical surface.

[0112] In particular, when the lens forming element 4 moves axially (i.e. along the optical axis A), tilts relative to the optical axis A (or relative to the base 21) or bends out of the plane, the curvature of the central region 23 deforms accordingly, which allows adjustment of the spherical power (the lens forming element 4 moves along the optical axis A), the prismatic power (the lens forming element 4 is tilted) and the cylindrical power (the lens forming element is bent out of its initial plane P), which gives the region 23 a cylindrical curvature / component.

[0113] In particular, in the absence of a pressure difference across the membrane 22 of the optical device 1, its shape is very similar to Z1 -1 Zernike function. To achieve a pure cylindrical shape (zero degrees on the reference axis), a spherical component can be generated by increasing / decreasing the pressure of the liquid L in the container 2 of the optical device 1 relative to the ambient pressure, where Figure 3 Shows Δp>0;

[0114] Alternatively, if Figure 4 As shown, the degree of astigmatism (cylindricity) can also be controlled by deforming the lens-forming element 4 in the (initial) film plane, e.g. Figure 4 As shown in (A) and (B), the aperture is deformed into a non-circular shape (such as an ellipse / rounded rectangle) in the plane by means of the lens shaping element 4. Here, the ideal shape can be determined by minimizing the deviation from the desired wavefront.

[0115] In this case, the astigmatism (Z2 -2 ) degrees and sphere (Z2 0 ) degrees are related by fixed relationships. (e.g. 0 steradian with 0 cylinder) Additional spherical adjustable elements are required to achieve all necessary degrees of freedom.

[0116] In addition, if Figure 1 As shown, the bottom 21 of the container 2 is (e.g. integrally) connected to the circumferential side wall 24 of the container 2, which includes a face side 24a, to which a flexible sealing element 25 can be connected (e.g. glued), and the flexible sealing element 25 connects the side wall 24 to the lens forming element 4.

[0117] exist Figure 1 In the illustrated embodiment, the sphericity of the optical device 1 can be adjusted by moving the lens shaping element 4 along the optical axis A to increase the pressure in the internal space 3 of the container 2 and thereby increase the spherical curvature of the region 23 of the membrane 22, or to reduce the pressure in the internal space 3 and thereby reduce the spherical curvature of the region 23.

[0118] Alternatively or additionally, the pressure in the container 2 may be adjusted according to Figure 5 The adjustment is made by pumping the liquid L from the liquid reservoir 28 through the inlet 26 into the inner space 3 of the container 2 by means of the pump 27 , or by pumping the liquid L from the inner space 3 into the liquid reservoir 28 .

[0119] Figure 6 Shows Figure 1 A variant of the embodiment is shown, in which here the side wall 24 forms a separate element relative to the transparent bottom 21 , which is connected, in particular glued, to the side wall 24 .

[0120] also, Figure 7 The following configuration is shown: In this configuration, Figure 1 , Figure 5 and Figure 6 The separate sealing element 25 shown is omitted. Alternatively, the membrane 22 is connected to the facing side 24a of the side wall 24 and thus comprises the sealing element as an integral part.

[0121] Figure 8A further embodiment of the optical device 1 according to the invention is shown, wherein here the rigid bottom 21 of the container 2 shown in the above-described embodiment is replaced by a bottom in the form of a transparent and elastically deformable further membrane 21, which is connected to a side wall 24, which in this case forms a rigid further lens-forming element 24 which defines a central area 29 of the further membrane 21.

[0122] In particular, in this dual-surface embodiment, the additional fixed and rigid lens-forming element 24 preferably comprises the same clear aperture as the deformable lens-forming element 4 .

[0123] Here, in particular, the spherical degree (the combined effect of the two membrane areas 23, 29) can be dominated by one of the membranes 22, 21 (if the stiffness is significantly different) and can be controlled by varying the liquid pressure, for example by axial movement of one or both lens-forming elements 4, 24 (or by means of Figure 5 The pump 27 shown is controlled.

[0124] Furthermore, prismatic power can be controlled by tilting the lens forming elements 4, 24 relative to each other, while cylindrical power can be controlled by bending the deformable lens forming element 4 out of plane, as will be described in more detail below.

[0125] In addition, according to Fig. 9 In the embodiment shown, the membrane 22 can be a shell (e.g. a thin component formed of, for example, glass, a plastic material or a polymer and comprising, for example, a thickness in the range of 10 μm to 200 μm), characterized in that it can also have significant out-of-plane forces. This means that a pure cylindrical lens (without degrees on its reference axis) can be realized without a pressure difference on the shell 22. Moreover, the spherical degree can be (almost) completely determined by the shape of the further membrane 21 (given E1>>E2, where E1 and E2 correspond to Young's modulus, respectively).

[0126] Now, if Fig.10 It turns out that surprisingly it has been found that the cylinder can be adjusted by acting on a limited number of selected points S1, ... of the lens forming element 4. Thus, a precise control of the cylinder can be achieved with, for example, a relatively small number of linear actuators.

[0127] In particular, if Fig.10 As depicted for two different cylindrical angles, the desired deformation of the (annular) lens forming element 4 (for any cylindrical angle) can be achieved, for example, by displacing at least five points, wherein here, as an example, six points S1, ..., S6 are used, which are preferably equally spaced on the lens forming element 4 along the periphery 40 of the element 4.

[0128] In particular, the displacements of the element tilt (sphere and prism) and the liquid pressure (steradian) can be advantageously superimposed.Thus, the displacement of only six points along the optical axis A is sufficient to fully control the sphere, cylinder and prism.

[0129] In particular, Figures 11 to 14 In the different embodiments depicted in , the optical device 1 comprises an actuator system 30 which is configured to bend the deformable lens-forming element 4 out of the plane P so as to adjust the cylinder using only this relatively small number of point displacements.

[0130] In particular, if Fig.11 As shown, the actuator system 30 may include individual actuators 31, wherein each actuator 31 is constructed to displace one of the points S1, ..., S6 to bend the deformable lens forming element 4 out of the plane P in order to adjust the cylindrical degree, and in particular also other degrees (spherical and prismatic).

[0131] In particular, the respective actuator 31 may comprise a stator 32 and a mover 33 which may be moved along the optical axis A by means of the actuator 31 and which is coupled to the respective points S1 , . . . , S6 of the lens forming element 4 via compliant couplings 34 .

[0132] like Fig.11 As shown, the corresponding actuator 31 may be a linear push-pull actuator 31 which may displace the corresponding points S1 , . . . , S6 along the optical axis A / vertical axis A in opposite directions.

[0133] Alternatively, the respective actuator 31 may be configured to push against the respective point S1, ..., S6, wherein the restoring force is provided by the associated spring element 5, such as Fig.12 , Fig.13 and Fig.14 Here too, the corresponding actuator 31 can be used to adjust the spherical degree and / or prismatic degree.

[0134] In particular, according to Fig.12 , the corresponding spring element 5 may be a coil spring 5. Furthermore, the corresponding spring element 5 may be arranged in the inner space 3 (i.e. immersed in the liquid L) and supported on the bottom 21 of the container 2. In particular, the lens forming element 4 is coupled to the corresponding mover 33 via a point contact 35 and is connected to the corresponding spring element 5 via an opposite point contact 35.

[0135] and Fig.12 Instead, the corresponding spring element 5 can also be formed by a leaf spring 5 which can alternatively be supported on the side wall 24 of the container 2. Fig.13As shown in (A), the corresponding leaf spring 5 can extend radially inward from the side wall 24 and can be mounted to the side wall 24 via a seal 36 to prevent leakage of the container 2 (see Fig.13 (B)).

[0136] In addition, according to Fig.14 , the corresponding leaf spring 5 can also be Fig.14 (A) and Fig.14 (B) is supported on the side wall 24 outside the inner space 3 of the container 2, and can extend radially inward to connect with the lens forming member 4. In particular, Fig.14 In the illustrated embodiment, the lens molding 4 and the spring 5 may be integrally connected to each other and may form a single unit.

[0137] Fig.15 and Fig.16 and Fig.17 In combination, yet another embodiment of an actuator 300 is shown, which can be used in combination with other actuators of an actuator system or alone to adjust the cylinder of an optical device 1 .

[0138] according to Figures 15 to 17 , the actuator 300 is a bending (e.g. bimorph) actuator comprising an annular passive layer 4c arranged between a first annular active layer 4a and a second annular active layer 4b, wherein the layers 4a, 4b, 4c are comprised by or may even form a lens forming element 4, and wherein the first active layer 4a is configured to expand or contract anisotropically in a first direction D1, and wherein the second active layer 4b is configured to expand or contract anisotropically in a second direction orthogonal to the first direction D1, so that the lens forming element 4 is bent out of the plane P, so that the lens forming element 4 defines a cylindrical surface parallel to the cylindrical reference axis C1 (see Fig.15 ).

[0139] Expansion or contraction of the active layers 4a, 4b may be achieved as described above (eg by means of an electric field in the case where the active layers comprise piezoelectric material)

[0140] However, Figures 15 to 17 The bimorph actuator 300 depicted in FIG. 4 may allow adjustment of the cylinder of only one given reference axis. In this case, two such deformable lens-forming elements 4, 24 / actuators 300, 301 are required, whose cylinder reference axes C1, C2 form an angle of 45°, such as Fig.15 shown.

[0141] This configuration including two actuators 300, 301 is Fig.18 Here, the optical device 1 is combined as shown in FIG. Fig.181 , but the further lens-forming element 24 is now also deformable (like the lens-forming element 4), wherein, in the non-deformed state, the further lens-forming element 24 defines a further plane P', wherein, in order to adapt the cylinder of the optical device 1, the further lens-forming element 24 (like the lens-forming element 4) is constructed to bend out of the further plane P', so that the further lens-forming element 24 also defines a cylindrical surface or generates a cylinder. In order to achieve a variable reference axis, the two actuators 300, 301 can be rotated relative to each other by the 45°, as Fig.15 shown.

[0142] Fig.19 and Fig. 20 and Fig.21 In combination, a further embodiment of an actuator 302 of an optical device 1 according to the invention is shown, wherein here the actuator 302 is a bending (e.g. bimorph) actuator 300, which comprises an annular passive layer 4b and an annular active layer 4a, wherein the layers 4a, 4b are comprised by the lens-forming element 4 or even form the lens-forming element 4, and wherein the active layer 4a comprises adjacent segments S1, ..., S12 arranged side by side in a circumferential direction 40 of the active layer 4a, which segments are configured to be selectively activated to contract or expand isotropically or anisotropically. This allows variable out-of-plane bending of the lens-forming element 4, such as Fig. 20 and Fig.21 shown.

[0143] In particular, the active layer 4a may include twelve segments S1 , . . . , S12 , wherein each segment includes a length in the circumferential direction 40 , which corresponds to a central angle B of the ring-shaped active layer 4a of 30°.

[0144] Here too, the expansion or contraction of the respective segment S1 , . . . , S12 can be achieved as described above (for example by means of an electric field in the case where the segments comprise piezoelectric material).

[0145] In particular, such an actuator 302 may be used in any embodiment according to the present invention. In particular, Fig. 22 An application of such an actuator 302 is shown, wherein a lens-forming element 4 formed by the actuator 300 is resiliently mounted to a holding structure 7 (eg a fixed base) of an optical device 1 .

[0146] Using this coupling, the container 2 can be tilted relative to the optical axis A (e.g. by a suitable further actuator of the actuator system) to adjust the prismatic power of the optical device 1. Furthermore, the container 2 or the bottom 21 can be moved relative to the lens shaping element 4 along the optical axis A of the optical device 1 to adjust the spherical power of the optical device 1.

[0147] also, Fig.23 A further embodiment of the invention is shown, in which here the cylinder, and in particular the sphericity, can be adjusted with the aid of individual actuators 31, wherein each actuator 31 comprises, for example, an electromagnet 32 ​​which moves a magnet 33 (mover) connected to the lens forming element 4 so that the lens forming element 4 can be bent out of its initial plane P, as described above (for example, by displacing at least five points, in particular six points, of the lens forming element 4, as described above).

[0148] For adjusting the prismatic power, the optical device 1 further comprises a transparent optical element 210, which is arranged between the membrane 22 and the bottom 21, such that the inner space 3 of the container 2 of the optical device 1 is divided into two separate zones 3a, 3b, wherein each zone 3a, 3b is filled with a liquid L, and wherein the optical device 1 comprises a flexible first side wall 240, which may be formed by a bellows, and a flexible second side wall 241, which may also be formed by a bellows, wherein the first side wall 240 connects the lens forming element 4 to the optical element 1, and wherein the second side wall 241 connects the optical element to the bottom 21. Thus, the bottom 21 can now be tilted relative to the optical element 210 (e.g. a transparent flat glass or polymer member) by the actuators of the actuator system to adjust the prismatic power of the optical device 1, while the actuator 31 can be used to displace the magnet 33 to adjust the cylinder and / or sphere of the optical device 1.

Claims

1. An optical device (1), in particular an ophthalmic device, comprising: - a container (2), the container (2) enclosing an inner space (3) of the container (2), wherein the inner space (3) is filled with a transparent liquid (L), and wherein the container (2) comprises a transparent bottom (21) and a transparent and elastically deformable membrane (22) opposite to the bottom (21), such that the liquid (L) is arranged between the membrane (22) and the bottom (21), - a deformable annular lens-forming element (4), which is connected to the membrane (22) such that a peripheral edge (41) of the lens-forming element (4) defines a central region (23) of the membrane (22), such that light can pass through the container (2) via the central region (23) and the bottom (21), wherein, in the non-deformed state, the edge (41) lies in a plane, and - an adjustable sphericity and an adjustable cylinder, wherein, in order to adapt the cylinder of the optical device (1), the lens-forming element (4) is designed to be curved out of the plane (P).

2. The optical element according to claim 1, wherein In order to adapt the cylinder of the optical device (1), the lens-forming element (4) is configured to be bent out of the plane (P) so that the edge (41) of the lens-forming element (4) coincides with a cylindrical surface.

3. The optical device according to claim 1 or 2, wherein: The optical device (1) also includes an adjustable prism power.

4. An optical device according to one of claims 1 to 3, wherein: The bottom (21) is connected to the peripheral side wall (24) of the container (2).

5. The optical device according to claim 4, wherein: The side wall (24) is formed integrally with the bottom (21).

6. The optical device according to claim 4, wherein: The side wall (24) and the bottom (21) are separate elements connected to each other.

7. An optical device according to one of claims 4 to 6, wherein: The membrane (22) is connected to the side wall (24).

8. The optical device according to one of claims 1 to 6, wherein: The container (2) comprises a separate circumferential and flexible sealing element (25) connecting the lens-forming element (4) to the side wall (24) or the bottom (21).

9. The optical device according to claim 1, wherein: The bottom (21) forms an additional membrane (21) capable of elastic deformation, and wherein the optical device (1) comprises an annular additional lens-forming element (24), which is connected to the additional membrane (21) so that the circumferential edge (42) of the additional lens-forming element (24) defines a central area (29) of the additional membrane (21).

10. The optical device according to claim 9, wherein: The additional lens-forming element (24) is an additional lens-forming element (24) that is capable of deformation, wherein, in a non-deformed state, the edge (42) of the additional lens-forming element (24) defines an additional plane (P'), wherein, in order to adjust the cylindrical power of the optical device (1), the additional lens-forming element (24) is constructed to bend outside the additional plane (P').

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