Electroactive lens with raised resistive bridges

Abstract

An electroactive lens with raised resistive bridges is disclosed. The resistive bridges can connect many ring electrodes in an electroactive lens with a relatively small number of bus lines. These resistors are typically large to prevent excessive current consumption. Typically, they are placed in the same plane as the ring electrodes, which means that the ring electrodes are further apart or made discontinuous to accommodate the resistors. But further separating the ring electrodes or making them discontinuous degrades the optical quality of the lens. Placing the ring electrodes and resistors on layers separated by an insulator allows the ring electrodes to be closer together and continuous and have a high enough resistance to limit current consumption. It also relaxes the constraints on feature size and placement during processing to make the lens. And because the resistors and electrodes are on different planes, they can be formed of materials with different resistivities.

Description

[0001] This application is a divisional application of patent application No. 202210305121.1, filed on November 7, 2016, entitled "Electroactive Lens with Protruding Resistive Bridge".

[0002] Cross-reference to related applications

[0003] This application claims priority to U.S. Application No. 62 / 321,501, filed April 12, 2016, which is incorporated herein by reference in its entirety. Background Technology

[0004] Electroactive lenses can be fabricated using several methods, including patterning a series of concentric electrodes of conductive material on a first substrate, and then sandwiching a liquid crystal layer between the first substrate and a second substrate opposite to the first substrate. The second substrate may have one or more circular patterns of conductive material patterned thereon, or any other shape matching or extending beyond the regions of the patterned electrodes, such that a circuit creating a voltage field between the two substrates can be formed. When an electric field is applied to the electrodes, the liquid crystal material between the two substrates changes its refractive index.

[0005] A lens can be created by applying a voltage field gradient at different electrode locations on the lens, thereby generating a refractive index gradient. The more electrodes used, the finer the resolution of the refractive index gradient that can be created. This results in a smoother wavefront curvature, thus providing a higher quality optical device.

[0006] However, increasing the number of electrodes also increases the complexity of the electronics and the photoresist components that supply power to the electrodes. Therefore, methods have been developed that allow a few power lines to apply voltage gradients across more electrodes. Specifically, N power lines can be used to apply voltage gradients across M>N electrodes via resistive bridges between them. In these electroactive lenses, each of the M / Nth electrodes is connected to a power line, and the other electrodes are coupled to each other via resistive bridges.

[0007] In conventional electroactive lenses with resistive bridges, the resistive bridges are fabricated in a way that the electrode rings are no longer continuous, thus reducing optical quality. This problem can be partially solved by fabricating the resistive bridges in the same plane as the electrodes and placing resistors between adjacent electrodes. In some cases, there are additional disadvantages, including the use of extremely high resistivity materials that are difficult to manufacture in a controlled manner, and the need to fill the entire gap between the electrodes with resistive material, requiring the filling of a large area. Generally, it is desirable to reduce the gap between the electrodes to improve optical performance, but this may exacerbate the difficulty in fabricating resistive components. Summary of the Invention

[0008] The inventors have recognized that existing solutions to the problem of reducing the complexity of drive channels in electroactive lenses introduce a new problem: excessive power consumption in electroactive lenses. Without a resistive bridge, a typical lens design might consume only nanoamps of current. However, the resistive bridge provides a path for current to flow from one drive channel to other drive channels. This additional current flow leads to an undesirable increase in the power consumption of the electroactive lens.

[0009] The inventors have recognized that increasing the resistance of the resistive bridge reduces this increased power dissipation. In some cases, the resistance can be increased by increasing the size of the resistor. However, mounting a larger resistor in the same plane as the electrodes means that, to mount a larger resistor, the gap between the electrodes must be larger, the electrodes must be interrupted, or both.

[0010] Unfortunately, creating a larger, high-resistance bridge within such a small space is extremely difficult. Furthermore, interruptions in the electrode gaps degrade the lens's optical performance: etching away a portion of the electrode to make room for the resistive bridge compromises electrode integrity, thus reducing the lens's optical performance. Adding to the problem is that the gaps between the electrodes should be minimized as much as possible to reduce the size that degrades optical performance, further increasing the challenge of increasing the resistance of the resistive bridge.

[0011] Fortunately, this technology solves these problems by providing larger, higher resistance bridges without degrading the optical performance of the lens. In these designs, the electrodes can remain continuous and close together. Furthermore, there is no need to remove electrodes or sacrifice surface area to make room for the resistive bridge.

[0012] Embodiments of this technology include an electro-optic lens comprising a first substantially transparent substrate, a plurality of electrodes disposed on the surface of the first substantially transparent substrate, an insulating layer disposed on the plurality of electrodes, and a resistive bridge disposed on the insulating layer. The resistive bridge connects a first electrode to a second electrode of the plurality of electrodes via holes patterned into the insulating layer. In operation, a voltage is applied to the first electrode via the resistive bridge to change the refractive index of an electroactive material (such as a (bistable) liquid crystal).

[0013] The plurality of electrodes may include a plurality of concentric ring electrodes, wherein the first electrode is a first concentric ring electrode and the second electrode is a second concentric ring electrode. In these cases, the first concentric ring electrode may have a constant width.

[0014] The plurality of electrodes may be formed of a first material having a first sheet resistance, and the resistive bridge may be formed of a second material having a second sheet resistance higher than the first sheet resistance.

[0015] An insulating material may be disposed between the first electrode and the second electrode. This insulating layer may span a gap of less than approximately 3 micrometers between the first electrode and the second electrode.

[0016] A resistive bridge may have a resistance of at least about 2.5 MΩ and an aspect ratio of about 25:1. Resistive bridges may comprise nickel, chromium, indium tin oxide, resistive polymers (e.g., PEDOT:PSS), or any combination or alloy thereof.

[0017] The resistive bridge may include multiple resistive segments, each of which is electrically connected to a corresponding pair of electrodes. The multiple resistive segments may include a first resistive segment having a first width and a second resistive segment having a second width greater than the first width. The multiple resistive segments may also include a first resistive segment having a first length and a second resistive segment having a second length greater than the first length. Furthermore, at least one of the multiple resistive segments may have a curved or bent edge.

[0018] Embodiments of this technology also include a method for fabricating an electro-optic lens. In one example of this method, a plurality of electrodes are formed on a substrate. An insulating material layer is deposited on the electrodes. Next, a plurality of vias are formed in the insulating material layer. Each of the plurality of vias is connected to a corresponding electrode among the plurality of electrodes. A resistive material is deposited on the insulating material layer and in the plurality of vias. The resistive material is patterned to form a plurality of resistors. Each of the plurality of resistors is connected to a corresponding electrode among the plurality of electrodes. Optionally, a bus line electrically connected to the electrodes and resistors may be formed.

[0019] In some cases, forming the plurality of electrodes includes forming a plurality of concentric ring electrodes. In these cases, forming the plurality of concentric ring electrodes may include forming a first concentric ring electrode, the first concentric ring electrode being spaced apart from a second concentric ring electrode by a gap of less than approximately 3 micrometers. Each concentric ring electrode may have a constant width (the width may be the same or different between the concentric ring electrodes).

[0020] The resistive material can have a sheet resistance higher than that of the plurality of electrodes. It can be patterned to form at least one resistor having a resistance of at least approximately 2.5 MΩ, at least one resistor having an aspect ratio of approximately 25:1, or both. In some cases, a first resistor segment having a first width and a second resistor segment having a second width greater than the first width can exist. Similarly, a first resistor segment having a first length and a second resistor segment having a second length greater than the first length can exist. The resistive material can be patterned to form at least one resistor with curved edges.

[0021] Another embodiment includes an electroactive contact lens having a substrate optical element and an electroactive element embedded within the substrate optical element. The electroactive element includes a plurality of electrodes, an insulating layer disposed on the plurality of electrodes, and a resistive bridge disposed on the insulating layer. The resistive bridge connects a first electrode of the plurality of electrodes to a second electrode of the plurality of electrodes via a hole patterned into the insulating layer.

[0022] It should be understood that all combinations of the foregoing concepts and the additional concepts discussed in more detail below (provided that such concepts are consistent with each other) are contemplated as part of the inventive subject matter disclosed herein. In particular, all combinations of the claimed subject matter appearing at the end of this disclosure are contemplated as part of the inventive subject matter disclosed herein. It should also be understood that terms expressly used herein and that may also appear in any disclosure incorporated by reference should be given the meaning most consistent with the specific concepts disclosed herein. Attached Figure Description

[0023] Those skilled in the art will understand that the accompanying drawings are primarily for illustrative purposes and are not intended to limit the scope of the inventive subject matter described herein. The drawings are not necessarily drawn to scale; in some cases, aspects of the inventive subject matter disclosed herein may be enlarged or magnified in the drawings to facilitate understanding of different features. In the drawings, similar reference numerals generally refer to similar features (e.g., functionally similar and / or structurally similar elements).

[0024] Figure 1 This illustrates an electrically active lens without a resistive bridge between the electrodes.

[0025] Figure 2A This illustrates the case where there is no electrical connection supplying power to the electrodes. Figure 1 Electrodes in an electroactive lens.

[0026] Figure 2B Showing the addition of bus lines Figure 1 and Figure 2A The electrodes.

[0027] Figure 3 A schematic diagram of an electrically active lens without a resistive bridge is shown.

[0028] Figure 4 Showing the flow Figure 3 The current flow in each drive channel of the electroactive lens shown.

[0029] Figure 5A A plan view of an electrically active lens with an in-plane resistive bridge is shown.

[0030] Figure 5B A schematic diagram of an electrically active lens with resistive bridges R1 to R9 is shown.

[0031] Figure 6 The typical current flow through each drive channel of the electroactive lens shown in Figure 5 is illustrated.

[0032] Figure 7 An electrically active lens with 100 kΩ resistive bridges R1 to R9 is shown.

[0033] Figure 8 Show Figure 7 The current flow in the electroactive lens shown.

[0034] Figure 9 An electroactive lens with a 2.5 MΩ resistive bridge is shown.

[0035] Figure 10 Showing the flow Figure 9 Typical current flow in each drive channel of the electroactive lens shown.

[0036] Figure 11 A cross-section of an electrically active lens with a raised resistive bridge is shown.

[0037] Figures 12A-12C Show Figure 11 Different views of the electrodes, resistors, and busbars of the electroactive lens.

[0038] Figure 12D A raised resistive bridge with a curved bridge segment is shown.

[0039] Figure 12E A raised resistive bridge with bridge segments of variable width is shown.

[0040] Figure 13 An electrically active contact lens with a raised resistive bridge is shown.

[0041] Figure 14 The process for fabricating an electroactive lens in which a resistive bridge is disposed on an insulating layer above an electrode layer is shown. Detailed Implementation

[0042] This application discloses electroactive lenses in which electrodes are connected to raised resistive bridges, including electroactive contact lenses and electroactive intraocular lenses. For example, the resistive bridge can be disposed on an insulating layer surrounding the electrodes. Placing the resistive bridge and electrodes on opposite sides of the insulating layer provides many advantages over electroactive lenses without resistive bridges and electroactive lenses with conventional resistive bridges. Compared to electroactive lenses without resistive bridges, electroactive lenses with raised resistive bridges can support more electrodes with fewer bus lines. Furthermore, compared to electroactive lenses with conventional resistive bridges, electroactive lenses with raised resistive bridges can support ring electrodes that are both continuous and closer together because resistors are not disposed between the ring electrodes. Continuous, closely spaced electrodes provide better optical performance than discontinuous or widely spaced electrodes.

[0043] A raised resistive bridge can be too large, meaning it is less likely to break when it buckles due to its larger surface area. As explained below, a larger raised resistive bridge also has higher resistance and lower power consumption. Low power consumption is particularly beneficial in contact lenses or intraocular lenses because the available power in such small devices is limited, and the battery size of the power storage device is consequently small. These raised resistive bridges enable lower power consumption while maintaining the optical capabilities provided by the device's design.

[0044] Furthermore, electroactive lenses with raised resistive bridges are easier to fabricate than those with conventional resistive bridges because the raised resistive bridges do not need to be precisely sized, shaped, or positioned as conventional resistive bridges. In other words, the raised resistive bridges can be fabricated with coarser resolution features because they extend beyond the electrodes and are not part of the optical region. As a result, electroactive lenses with raised resistive bridges can be fabricated on flexible surfaces using simpler photolithography or inkjet printing. And because they are on a different plane than the electrodes, the raised resistive bridges can also be made of different materials than the electrodes. For example, the electrodes can be made of conductive transparent materials such as indium tin oxide (ITO), and the raised resistive bridges can be made of materials with a higher resistivity than ITO.

[0045] Electroactive lens without resistive bridge

[0046] Figure 1An exploded perspective view of an electroactive lens 100 without resistive bridges is shown. The electroactive lens 100 includes a lower substrate 110 patterned with a set of concentric ring electrodes 205 and conductive connection pads 115. Conductive bus lines 220 connect the respective electrodes 205 to the respective conductive connection pads 115. The electrodes 205, bus lines 220, and connection pads 115 can be formed from a transparent conductive material (such as indium tin oxide (ITO)) deposited on the lower substrate 110 and patterned using standard photolithography techniques. An upper substrate 130 forms the other half of the lens 110. The bottom side of the upper substrate 130 is coated with a layer of transparent conductive material that serves as another electrode (e.g., ground plane 135). A liquid crystal material layer 120 is sandwiched between the upper substrate 130 and the lower substrate 120 to form the lens 110.

[0047] In operation, the individually controllable voltage at each bus line 220 can be used to modulate the refractive index of the liquid crystal material 120 between the corresponding ring electrode 220 and the ground plane 135. For example, the voltage applied to the bus line 220 can be selected to generate a spherical wavefront when the lens 100 is positioned in the path of a plane wave. The voltage can also be selected to deviate from only the spherical wavefront. Such deviation can be useful for correcting higher-order aberrations (an example being spherical aberration).

[0048] Figure 2A and 2B Showing more details Figure 1 The concentric circular electrodes 205 of the electroactive lens 100. Figure 2A A lens 100 is shown, either without or configured to supply power to the electrodes 205 via electrical connections. The circular electrodes 205 are typically made of a transparent but conductive material (such as indium tin oxide (ITO)) patterned on a transparent substrate (such as glass or plastic). Between each electrode 205 are gaps 210 without conductive material to prevent electrical connections between the electrodes 205. These gaps 210 (nineteen are shown) may be left unfilled or filled with a non-conductive material, such as silicon dioxide (SiO2). In many cases, it is desirable to make the gaps as small as possible, with typical gap sizes ranging from 1 to 3 micrometers. Smaller or larger gaps are also possible. In this example, twenty electrodes 205 are shown, but more are typically used, possibly hundreds or thousands.

[0049] Lens 100 may include an insulating layer (not shown) on top of the circular electrode 205 and the gap 210. This insulating layer may be made of a non-conductive but optically transparent material deposited above the electrode 205, for example, a 125 nm thick SiO2 layer. A series of holes 200 (twenty shown) are patterned in the insulating layer to expose a portion of each underlying electrode 205. The following is about... Figure 2B To explain the purpose of these holes 200.

[0050] Figure 2B Electrode 205 is shown, with bus lines 220 (twenty shown) connected to the respective electrode 205 via corresponding holes 200. The bus lines 220 are made of a conductive material (e.g., nickel). They are typically about 10 micrometers wide, but can be narrower (e.g., 1 micrometer) if space is limited and power consumption is low, or wider (e.g., 100 micrometers) if power consumption is high. Each bus line 220 can be up to 10 mm long, depending on the circuit design.

[0051] In operation, bus lines 220 supply electrical power to electrodes 205. Each bus line 220 delivers power only to its designated electrode 205 and not to any other electrode 205. An insulating layer prevents the bus line 220 from short-circuiting or connecting to other electrodes below it and only allows the bus line 220 to connect to the desired electrode 205 through through-holes 200 in the insulating layer.

[0052] Figure 1 The example lens 100 shown in Figure 2 uses one bus line per electrode. In this example design with twenty electrodes, providing twenty bus lines and twenty electrically driven channels is manageable; however, as the lens has more electrodes, using one bus line per electrode can become problematic. Additional bus lines can degrade the optical quality of the lens by blocking light and adding unwanted diffraction sources, and each additional electrical channel adds complexity and cost to the electronics. These problems can be mitigated by adding resistors between the electrodes, thus allowing only a subset of the electrodes to be connected to the bus lines. Electrodes not connected to the bus lines are powered by current delivered via resistive bridges and adjacent electrodes. This reduces the number of bus lines and electrically driven channels, but can increase power consumption, as described in more detail below.

[0053] Figure 3 An electrically active lens without a resistive bridge is shown (e.g., Figure 1 A typical electrical schematic of lens 100 in Figure 2 is shown. Drive signals are provided by analog output voltage sources 5, 10, 15, 20, 25, 30, 35, 40, 45, and 50. These voltage sources are supplied by a controller (not shown) (such as an application-specific integrated circuit (ASIC)) embedded in or electrically coupled to the electroactive lens. Figure 3 In the schematic diagram, capacitors C1 to C10 on the left represent the capacitance created by the electrode-modulated liquid crystal layer (not shown). The ground symbol indicates that the ground plane is the substrate opposite to the substrate with the patterned electrodes and the relative potential of the analog output.

[0054] In this example, the driving signal is a square wave oscillating at 100 Hz, with peak-to-peak voltage amplitudes from voltage sources 5 to 50 of 0.57, 0.62, 0.69, 0.76, 0.83, 0.92, 1.03, 1.13, 1.27, and 1.5 volts, respectively. These voltages are determined by the desired delay gradient in the liquid crystal to create the desired optical effect. A relationship commonly referred to as the V10-V90 specification exists between the liquid crystal response and a voltage known as the threshold voltage. This specification indicates the range of voltages required to move liquid crystal molecules within 80% of their range. The voltage can be adjusted to compensate for other design variables, such as the distance from the electrode to the liquid crystal or the thickness of the liquid crystal layer.

[0055] Figure 4 This illustrates the flow through an electrically active lens (e.g., without a resistive bridge). Figure 1-3 The typical current flow in each drive channel (as shown in the examples) is 120 nanoamps (120 × 10⁻⁶). -9 A). If the control circuit of the electroactive lens draws another 130 nanoamps, the current is low enough that the lens 100 can operate for approximately 40 hours using a 10 microamp-hour battery that is small enough to be embedded in an electroactive ophthalmic lens (such as an electroactive contact lens or an electroactive intraocular lens).

[0056] Electroactive lens with in-plane resistive bridge

[0057] Figure 5A A plan view of an electrode 34 connected in a (prior art) electroactive lens by an in-plane resistive bridge 38, from U.S. Patent 9,280,020 to Bos et al., which is incorporated herein by reference in its entirety. The electrode 34, the in-plane resistive bridge 38, and the central disk electrode 35 are formed by patterning an electrode layer 30 on a substrate 22. As shown in close-up region 2-2, the in-plane resistive bridge 38 spans a gap 36 (e.g., an open space) between adjacent electrodes 34, thereby reducing the number of input connections 70 between the electrodes 34 and a voltage source (not shown).

[0058] Close-up 2-2 also shows the discontinuities caused by the in-plane resistive bridge 38, such as variations in width and corners (sharp corners), that prevent the electrodes 34 from forming a perfect loop. If the resistive bridge 38 is large enough, these breaks or discontinuities can degrade the optical performance of the electroactive lens and the electrical performance of the electrodes. Typically, in-plane resistive bridges that achieve good optical performance are 2 micrometers wide and 4 micrometers long. However, resistors of this size, with only about 2 square millimeters of resistive material, make it difficult to use materials with a resistivity or sheet resistance high enough to provide the desired resistance while keeping power dissipation low, as explained below. Increasing the area increases the resistance, but requires larger gaps between the electrodes 34, greater discontinuities in each resistor 38, or both. Figure 5A As shown, forcibly inserting into electrode 34 to elongate resistor 38 can provide a region with a larger aspect ratio of the resistor, so a larger amount of resistive material can be used, resulting in higher resistance, but the integrity and performance of electrode 34 are thus compromised. Figure 5A The electrode 38 shown is typically 30 micrometers long and 3 micrometers wide (approximately 10 square meters), which provides suitable resistance but reduces optical performance.

[0059] Figure 5B An electrical schematic diagram of an electroactive lens with in-plane resistive bridges R1 to R9 is shown. Each of these resistors has a resistance value of 2000 ohms. These resistive bridges are formed in the same plane as the electrodes between adjacent electrodes. At this resistance value, they can be small enough not to degrade the optical quality of the electroactive lens. That is, they are small enough to fit within the gap between the electrodes and not diffract or scatter incident light in a way that would block or obstruct the user's ability to see clearly through the lens. However, the resistors significantly increase the current consumption of the lens.

[0060] Figure 6 Typical current flow through each drive channel of the electroactive lens shown in Figure 5 is illustrated. The maximum current is 117 microamps (117 × 10⁻⁶). -6 A). At this current consumption, the electroactive lens will deplete a 10 microamp-hour battery in about five minutes, which is too short for most ophthalmic applications to be practical.

[0061] Figure 7 An electrical schematic diagram of an electroactive lens with in-plane resistive bridges R1 to R9, each having a resistance of 100,000 ohms, is shown. These resistive bridges are relatively large, thus increasing the likelihood of degrading the lens's optical performance. The increased resistance reduces the lens's current consumption, but the reduction is insufficient to make the lens practical for ophthalmic applications.

[0062] Figure 8 It shows Figure 7 The current flow through the lens is shown. Despite the high resistance, the peak current consumption is almost 2.5 microamps (2.5 × 10⁻⁶). -6 A), this is better than Figure 3 The lens shown without the resistive bridge consumes more than twenty times the current. Even at this current consumption level, this electrode / resistor configuration would have a battery life too short to be used in contact lenses or intraocular lenses.

[0063] Figure 9 An electrical schematic of an electroactive lens with resistive bridges modified to each have a resistance of 2,500,000 ohms (2.5 MΩ) is shown. These resistive bridges are approximately 50 micrometers long × 2 micrometers wide, which is large enough to degrade the optical performance of the electroactive lens. At this resistance, the current begins to approach the resistance between the electrodes in an electroactive lens without resistive bridges in the circuit. However, the resistive bridges are also large enough that the electrodes must be further separated, bent, or kinked to fit the resistive bridges between them. Further separating the electrodes or changing their shape degrades the optical quality of the lens, making it unsuitable for many ophthalmic applications.

[0064] Figure 10 It shows the flow through Figure 9 The typical current flow in each drive channel of the electroactive lens described in the figure. The maximum current is 200 nanoamps (200 × 10⁻⁶). -9 A) This is close to the power consumption level of a lens without a resistive bridge. The current consumption is low enough that the battery life of the lens roughly matches that of an electroactive lens without a resistive bridge, but the optical quality of the lens is worse than that of an electroactive lens without a resistive bridge. As a result, even though a lens with a 2.5 MΩ in-plane resistive bridge has a battery life long enough to be used as a contact lens or intraocular lens, it cannot be used as a practical contact lens or intraocular lens.

[0065] Electroactive lens with convex resistive bridge

[0066] Figure 11-1Figure 2 illustrates an electroactive lens with a raised resistive bridge and concentric ring electrodes, and how they can be used in an electroactive lens. The resistor is not located within the gap between the electrodes or at the break in each electrode, but rather between the electrodes and the resistor connected through vias in the insulating layer. This results in continuous electrode rings because it eliminates the need to remove surface areas from the electrodes to make room for the resistor. It also enables resistors with larger aspect ratios. This longer aspect ratio allows the resistor to be fabricated with very high total resistance and smaller sheet resistance. For example, for a material with a sheet resistance of 100 kΩ per square (which is a common and easily fabricated type of material), a resistor between busbar connection points can have a resistance of 2.5 MΩ and an aspect ratio of 25:1. Other resistances and aspect ratios are also possible, depending on the resistive bridge material and lens design guidelines, which may include desired battery life.

[0067] Another advantage of raising the resistive bridge above (or below) the level of the electrodes is that the resistive bridge material can be different from the electrode material. This allows the material to be selected for electrodes with desired optical quality but potentially low resistance, and different materials to be selected for resistors with high resistance but potentially low optical quality. Because resistors comprise such a small area as a lens, they can even be made of opaque materials that have no meaningful impact on the optical quality of the lens.

[0068] Figure 11 A cross-section of a portion of an electroactive lens with a raised resistive bridge (resistor) 350 is shown. This resistive bridge 350 is electrically connected to several electrodes 305a-305e (collectively referred to as electrodes 305), which are patterned onto a substrate 310. In ophthalmic lenses (such as contact lenses), there may be dozens to hundreds of electrodes 305 spanning a width of approximately 10-20 mm, with each electrode 305 having a width on the order of several micrometers to several millimeters (e.g., 0.5 μm, 1 μm, 2 μm, 2.5 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, 20 μm, 30 μm, 40 μm, 50 μm, 100 μm, 250 μm, 500 μm, 1 mm, 1.5 mm, 2 mm, or any other value or range between approximately 0.5 μm and approximately 2 mm). According to the implementation, the electrodes 305 may be of the same or different widths, and may have a disc-shaped electrode at the center of the lens.

[0069] Unlike electrically active lenses with conventional resistive bridges, Figure 11Each of the electrodes 305 shown is of uniform width with no discontinuities. Furthermore, the gaps between adjacent electrodes are relatively small. For example, these gaps can range in size from nanometers to micrometers (e.g., 100 nm, 200 nm, 250 nm, 300 nm, 400 nm, 500 nm, 1 μm, 2 μm, 2.5 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, or 10 μm, or any other value or range up to approximately 10 μm). Electrodes 305 can be relatively thin, for example, less than 200 nanometers (nm), preferably less than 40 nm.

[0070] An insulating layer 300 covers the electrode 305, and busbar vias 330a and 330b (collectively referred to as busbar vias 330) are patterned into the insulating layer 300. For example, the insulating layer 300 may be a 120 nm thick silicon dioxide layer or a 0.5 μm thick SU-8 layer. Resistor vias 340a-340c (collectively referred to as resistor vias 340) are also patterned into the insulating layer 300. A resistive bridge 350 is then formed such that the bottom electrode 305 is connected via the vias 330 and 340, through the resistive bridge 350. Busbars 315a and 315b (collectively referred to as busbars 315) are connected to both the resistive bridge 350 and the electrodes 305a and 305e via the vias 330a and 330b, respectively. Electrodes 305a and 305e are directly powered by bus lines 315a and 315b, while electrodes 305b-305d are indirectly powered through resistive bridge 350.

[0071] The sheet resistance of the resistive bridge 350 can range from approximately 0.1 MΩ per square to approximately 100 MΩ per square or more. The sheet resistance of the insulating layer 300 is greater than approximately 10 MΩ per square. 18 Ω, ideally infinite. The resistance of electrode 305 is less than approximately 200 Ω per square. Other measures of resistance may be used depending on the optical effects to be achieved. The resistive layer may be relatively thin, for example, less than 200 nanometers (nm), preferably less than 40 nm.

[0072] although Figure 11 The diagram shows bus line 315 connected to resistive bridge 350 within bus line via 330 via a shared electrode 305; however, those skilled in the art of via design can make other configurations. For example, with the bus line on top of the resistive bridge material, the resistive bridge can occupy the entire bottom of the via. Similarly, with the resistive bridge on top of the bus line material, the bus line can also occupy the entire bottom of the via. Likewise, the resistive bridge can be connected to more or fewer electrodes.

[0073] Placing the resistive bridge 350 above the insulating layer 300 provides more space for the resistor construction, allowing for a higher aspect ratio to be used without compromising or disrupting the integrity of the electrodes 305. All else being equal, increasing the resistor's aspect ratio increases its resistance. Higher resistance translates to lower current consumption and longer battery life. A higher aspect ratio might not be possible if the resistor had to remain within the gap between the electrodes at the electrode plane.

[0074] Placing the resistive bridge 350 above the insulating layer 300 and the electrodes also provides greater flexibility in selecting materials for the resistor's construction when building resistors with high resistance, as well as greater robustness and tolerance. For example, the resistive bridge 350 can be made of a transparent conductive material (such as indium tin oxide) or a layer thin enough to be translucent (such as a micrometer-thick nickel layer). If the resistive bridge 350 is used in a reflective geometry, or if the resistive bridge 350 is relatively small, it can be made of an opaque material (e.g., a thicker metal layer).

[0075] Figure 12A and 12B A plan view of electrode 305, busbar 315, busbar via 330, resistor via 340, and resistive bridge 350 is shown. Figure 12B (This is a close-up view.) Busbar lines 315 (six shown) penetrate the insulation layer at busbar through-holes 315 in six locations, thereby electrically connecting to electrodes 305. Resistive bridges 350 are also connected at busbar through-holes 315. Resistive bridges 350 are connected to unpowered electrodes 305 through resistor-only through-holes 340 (fourteen shown).

[0076] Figure 12C Busbar line 315, busbar line via 330, resistor via 340, and resistive bridge 350 are shown, but without electrode 305. Although the resistive bridge 350 is shown as a set of straight segments (each of which can be considered a single resistive bridge), they could also be other shapes and sizes to provide better control over the desired resistance.

[0077] For example, Figure 12DA raised resistive bridge 350' is shown, having curved bridge segments 352a-352d (collectively referred to as bridge segments 352) connecting adjacent vias 330 and 340. In this case, the curved bridge segments 352 form a wavy or sinusoidal path between a pair of busbar vias 330. In other cases, the resistive bridge segments may take different non-straight (e.g., curved, twisted, or zigzag) paths from one via to the next. Moreover, each bridge segment may have a different curvature or path—some segments may have a larger radius of curvature than others, or take a different shape of path. This will increase the length and resistance of each segment and the resistive bridge as a whole. Curvature can also affect other electrical properties of the resistive bridge, including its inductance, capacitance, or both.

[0078] Similarly, Figure 12E A raised resistive bridge 350'' is shown, having segments 354a-354d (collectively referred to as variable-width bridge segments 354) whose width varies between segments. In this case, segment 354 protrudes in the middle, but other shapes can also be used. This variation can be used to provide resistors that compensate for resistance variations caused by changes in length between segments of the resistive bridge. The width of each segment can also be intentionally changed to create non-uniform resistance values ​​between segments. For example, the segment widths can be varied to create non-linear resistance gradients, such as parabolic resistance gradients. This parabolic resistance gradient can be used to create parabolic gradients of the electric field, resulting in lenses with fewer bus lines (and better optical quality).

[0079] Electroactive contact lens with raised resistive bridge

[0080] Figure 13 An electroactive contact lens 1300 with a raised resistive bridge 1350 is shown. The electroactive contact lens 1300 includes an electroactive lens element 1302 having an electroactive material (such as nematic liquid crystal or cholesteric liquid crystal) sandwiched between a pair of transparent substrates, like... Figure 1 As shown in lens 100. Liquid crystal can also be contained within a cavity defined by folding a single substrate onto itself. One of the surfaces opposite the liquid crystal material is patterned to include, for example... Figure 11 and 12A The image shows multiple concentric ring electrodes made of a transparent conductive material.

[0081] The electroactive lens element 1302 also includes, for example, Figure 11 The diagram shows a raised resistive bridge 1350 disposed on an insulating layer. This raised resistive bridge 1350 includes sections connecting electrodes to each other and connecting electrodes to bus lines 1320, as shown... Figure 11 and 12AAs shown. Bus line 1320 is connected to bus 1322, which is connected to the processor (here, ASIC 1324) via flexible printed circuit board (PCB) 1326. Flexible PCB 1326 also connects ASIC 1324 to toroidal power battery 1328 and to loop antenna 1330, as shown. Figure 13 As shown, both are concentric with the electroactive lens element 1302. All these components are fully or partially embedded in the substrate optics element 1304. The substrate optics element 1304 can provide additional optical power—that is, it can be used as a fixed lens—and can be formed from any suitable material, including soft hydrogels, such as those used in soft contact lenses.

[0082] In operation, the ASIC 1324 activates the electroactive lens element 1302 in response to signals received by the antenna 1330 or generated by one or more sensors (not shown) embedded in the electroactive contact lens 1300. The ASIC 1324 controls the optical power provided by the electroactive lens element 1302 by modulating the voltage applied to the electrodes via bus 1326, bus line 1320, and raised resistive bridge 1350. Because the raised resistive bridges 1350 are in a plane different from the electrodes, they can be relatively large (e.g., 2.5 MΩ) without degrading the optical performance of the lens. At this size, they also limit current consumption to a reasonable rate (e.g., on the order of 100-200 nA), allowing the battery 1328 to operate for a long time (e.g., 40 hours or longer) between recharges (e.g., via the coil antenna 1330) or before the electroactive contact lens 1300 is discarded.

[0083] Fabrication of an electroactive intraocular lens with a convex resistive bridge

[0084] Figure 14A process 1400 for fabricating an electroactive intraocular lens with raised resistive bridges is illustrated. In step 1402, a conductive material (e.g., ITO) is deposited on a transparent substrate (such as a flexible polymer). In step 1404, an electrode material is photolithographically patterned to form electrodes (e.g., concentric ring electrodes). Next, in step 1406, an insulating material layer (such as silicon dioxide) is deposited on the patterned electrodes. In step 1408, vias are photolithographically patterned into the insulating layer. In step 1410, resistive material is disposed on the insulating layer and in the vias to form electrical connections with the electrodes. Suitable resistive materials include, but are not limited to, alloys of nickel and chromium, oxygen-doped ITO, combinations of metals and oxides, and resistive polymers (such as poly(3,4-ethylenedioxythiophene)poly(styrene sulfonic acid) (PEDOT:PSS)). In step 1412, the resistive material is photolithographically patterned to form raised resistive bridges. In step 1414, a conductive material layer is disposed on the resistive bridge and the exposed insulating layer, and in step 1416, the conductive material layer is patterned to form a bus line.

[0085] in conclusion

[0086] While various embodiments of the invention have been described and illustrated herein, those skilled in the art will readily imagine various other means and / or structures for performing the functions described herein and / or obtaining one or more of the results and / or advantages described herein, and each of such variations and / or modifications is considered to be within the scope of the embodiments of the invention described herein. More generally, those skilled in the art will readily recognize that all parameters, dimensions, materials, and configurations described herein are intended to be exemplary, and actual parameters, dimensions, materials, and / or configurations will depend on one or more specific applications in which the teachings of the invention are used. Those skilled in the art will recognize or be able to ascertain many equivalent forms of the particular embodiments of the invention described herein using only conventional experimentation. Therefore, it is to be understood that the foregoing embodiments are presented merely as examples, and that embodiments of the invention may be practiced in ways other than those specifically described and claimed within the scope of the appended claims and their equivalents. The embodiments of the invention disclosed herein are directed to each individual feature, system, article, material, toolkit, and / or method described herein. Furthermore, any combination of two or more such features, systems, articles, materials, toolkits and / or methods (if such features, systems, articles, materials, toolkits and / or methods are consistent with each other) is included within the scope of this invention disclosure.

[0087] The embodiments described above can be implemented in any of a number of ways. For example, embodiments of the techniques disclosed herein can be implemented using hardware, software, or a combination thereof. When implemented in software, the software code can execute on any suitable processor or set of processors, whether provided in a single computing facility or distributed across multiple computers.

[0088] Furthermore, it should be recognized that a computer can be implemented in any of several forms, such as a rack-mount computer, desktop computer, laptop computer, or tablet computer. Additionally, a computer can be embedded in a device that is not generally considered a computer but has suitable processing capabilities, including a personal digital assistant (PDA), a smartphone, or any other suitable portable or stationary electronic device.

[0089] In addition, a computer may have one or more input and output devices. These devices can be used, among other things, to present a user interface. Examples of output devices that can be used to provide a user interface include a printer or display screen for visual presentation of output, and speakers or other sound-generating devices for audible presentation of output. Examples of input devices that can be used for a user interface include keyboards and pointing devices (such as mice, touchpads, and digitizers). As another example, a computer may receive input information via speech recognition or in other audible formats.

[0090] Such computers can be interconnected by one or more networks of any suitable form, including local area networks (LANs) or wide area networks (WANs), such as enterprise networks and intelligent networks (INs) or the Internet. Such networks can be based on any suitable technology, operate according to any suitable protocol, and can include wireless networks, wired networks, or fiber optic networks.

[0091] The various methods or processes outlined herein (e.g., methods or processes for designing and making the techniques disclosed above) can be decoded into software executable on one or more processors employing any of a variety of operating systems or platforms. Furthermore, such software can be written using any of several suitable programming languages ​​and / or programming or scripting tools, and can also be compiled into executable machine language code or intermediate code that executes on a framework or virtual machine.

[0092] In this respect, various inventive concepts can be implemented as a computer-readable storage medium (or multiple computer-readable storage media) (e.g., a computer memory, one or more floppy disks, compact disks, optical disks, magnetic tapes, flash memory, circuit configurations in field-programmable gate arrays or other semiconductor devices, or other non-volatile media or tangible computer storage media) encoding one or more programs that, when executed on one or more computers or other processors, perform methods implementing the various embodiments of the invention discussed above. The computer-readable medium or multiple computer-readable media may be transportable such that one or more programs stored thereon can be loaded onto one or more different computers or other processors to implement aspects of the invention as discussed above.

[0093] The terms "program" or "software" are used broadly herein to refer to any type of computer code or set of computer-executable instructions that can be used to program a computer or other processor to implement aspects of the embodiments discussed above. Additionally, it should be appreciated that, according to one aspect, one or more computer programs that perform the methods of the invention when executed do not need to reside on a single computer or processor, but can be distributed in a modular manner among several different computers or processors to implement aspects of the invention.

[0094] Computer-executable instructions can take many forms, such as program modules that execute on one or more computers or other devices. Generally, program modules include routines, programs, objects, components, data structures, etc., that perform specific tasks or implement specific abstract data types. Typically, the functionality of program modules can be combined or distributed as needed in various embodiments.

[0095] Furthermore, data structures can be stored in any suitable form on a computer-readable medium. For simplicity, a data structure can be shown as having fields associated by their positions within the data structure. Such relationships can be similarly implemented by allocating storage for fields in a computer-readable medium that have positions that convey the relationships between the fields. However, any suitable mechanism can be used to establish relationships between the information in the fields of a data structure, including the use of pointers, labels, or other mechanisms for establishing relationships between data elements.

[0096] Furthermore, various inventive concepts can be implemented as one or more methods, examples of which have been provided. Actions performed as part of said method can be ordered in any suitable manner. Therefore, even though actions are shown as sequential in the illustrative embodiments, embodiments can be constructed that perform actions in a different order than that illustrated (which may include performing some actions simultaneously).

[0097] All definitions defined and used in this document should be understood as control dictionary definitions, definitions incorporated by reference in other documents, and / or the general meaning of the terms defined.

[0098] The indefinite articles “a” or “an” used in this specification and claims shall be understood to mean “at least one” unless expressly indicated to the contrary.

[0099] The term “and / or” as used in this specification and claims should be understood as “any one or two” of the elements so combined (i.e., elements that exist together in some cases and separately in others). Multiple elements listed with “and / or” (i.e., “one or more” of the elements so combined) should be interpreted in the same manner. Elements other than those specifically identified by the “and / or” clause may optionally be present, whether related to or unrelated to those specifically identified. Thus, as a non-limiting example, the statement “A and / or B” when used in conjunction with open-ended language such as “comprising” may, in one embodiment, mean only A (optionally including elements other than B); in another embodiment, it may mean only B (optionally including elements other than A); in yet another embodiment, it may mean both A and B (optionally including other elements); and so on.

[0100] As used herein and in the claims, “or” should be understood to have the same meaning as “and / or” as defined above. For example, when dividing items in a list, “or” or “and / or” should be interpreted as inclusive, i.e., including at least one of several elements or a list of elements and optionally additional unlisted items, but also including more than one. Only terms that explicitly indicate the opposite (such as “the only one of…” or “exact one of…” or, when used in a claim, “consisting of…”) will refer to including exactly one element from several elements or a list of elements. In general, the term “or” as used herein, when preceded by an exclusive term (such as “either of both,” “one of…,” “the only one of…,” or “exact one of…”), should only be interpreted as indicating an exclusive alternative (i.e., “one or the other, but not both”). “Substantially consisting of…” when used in a claim should have its ordinary meaning as used in the field of patent law.

[0101] As used in this specification and claims, the term "at least one" in discussions of a list of one or more elements should be understood to mean at least one element selected from any one or more elements in the list of elements, but does not necessarily include at least one of every element specifically listed in the list of elements, and does not exclude any combination of elements in the list of elements. This definition also allows for the optional presence of elements other than those specifically identified in the list of elements referred to by the term "at least one," regardless of whether they are related to or unrelated to those specifically identified elements. Thus, as a non-limiting example, "at least one of A and B" (or equivalently, "at least one of A or B," or equivalently, "at least one of A and / or B") in one embodiment may mean at least one (optionally including more than one) A, where B is absent (and optionally includes elements other than B); in another embodiment, it may mean at least one (optionally including more than one) B, where A is absent (and optionally includes elements other than A); in yet another embodiment, it may mean at least one (optionally including more than one) A and at least one (optionally including more than one) B (and optionally includes other elements); and so on.

[0102] In the claims and in the description above, all conjunctions (such as “comprising,” “including,” “carrying,” “having,” “containing,” “involving,” “storing,” “constituting,” etc.) shall be understood as open-ended, that is, meaning including but not limited to. As set forth in Section 2111.03 of the U.S. Patent Examination Guidelines Manual, only the conjunctions “constituting of” and “substantially consisting of” shall be closed or semi-closed conjunctions, respectively.

Claims

1. An electro-optic lens, the electro-optic lens comprising: The first is a basically transparent substrate; Multiple electrodes are disposed on the surface of the first substantially transparent substrate; An insulating layer is disposed on the plurality of electrodes; as well as A resistive bridge disposed on the insulating layer connects a first electrode of the plurality of electrodes to a second electrode of the plurality of electrodes via a hole patterned into the insulating layer.

2. The electro-optic lens according to claim 1, wherein, The plurality of electrodes includes a plurality of concentric ring electrodes, wherein the first electrode is a first concentric ring electrode and the second electrode is a second concentric ring electrode.

3. The electro-optic lens according to claim 2, wherein, The first concentric ring electrode has a constant width.

4. The electro-optic lens according to claim 1, wherein, The plurality of electrodes are formed of a first material having a first sheet resistance, and the resistive bridge is formed of a second material having a second sheet resistance higher than the first sheet resistance.

5. The electro-optic lens according to claim 1, further comprising: An insulating material is disposed between the first electrode and the second electrode, the insulating layer spanning a gap of less than approximately 3 micrometers between the first electrode and the second electrode.

6. The electro-optic lens according to claim 1, wherein, The resistive bridge has a resistance of at least approximately 2.5 MΩ.

7. The electro-optic lens according to claim 1, wherein, The resistive bridge has an aspect ratio of approximately 25:

1.

8. The electro-optic lens according to claim 1, wherein, The resistive bridge comprises at least one of nickel, chromium, indium tin oxide, or a resistive polymer.

9. The electro-optic lens according to claim 1, wherein, The resistive bridge includes multiple resistive segments, each of which is electrically connected to a corresponding pair of electrodes among the multiple electrodes.

10. The electro-optic lens according to claim 9, wherein, The plurality of resistive segments include a first resistive segment having a first width and a second resistive segment having a second width, the second width being greater than the first width.

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