Shape memory alloy actuators and module assembly thereof

Abstract

This invention describes shape memory alloy (SMA) actuators and related methods. One embodiment of the actuator includes: a base; a plurality of buckle arms; and at least one first shape memory alloy wire coupled to one pair of buckle arms of the plurality of buckle arms. Another embodiment of the actuator includes a base and at least one dual piezoelectric chip actuator comprising a shape memory alloy material. The dual piezoelectric chip actuator is attached to the base.

Description

Technical Field

[0001] The embodiments of this invention relate to the field of shape memory alloy systems. More specifically, the embodiments of this invention relate to the field of shape memory alloy actuators and related methods. Prior Technology

[0002] Shape memory alloy ("SMA") systems have, for example, a moving assembly or structure that can be integrated with a camera lens element as an autofocus actuator. Such systems can be enclosed by a structure such as a shield. The moving assembly is supported to move on a support assembly by means of a bearing such as a plurality of ball bearings. A flexible element made of a metal such as phosphor bronze or stainless steel has a moving plate and a flexure. The flexure extends between the moving plate and the stationary support assembly and acts as a spring to allow the moving assembly to move relative to the stationary support assembly. The ball bearings allow the moving assembly to move with minimal resistance. The moving assembly and the support assembly are coupled by four shape memory alloy (SMA) wires extending between these assemblies. Each of these SMA wires has one end attached to the support assembly and one opposite end attached to the moving assembly. The suspension is driven by applying an electric drive signal to the SMA wires. However, such systems suffer from system complexity, resulting in a large system requiring a large coverage area and a large height clearance. Furthermore, this system fails to provide a high Z-stroke range with a compact, low-distribution coverage area. Summary of the Invention

[0003] This paper describes an SMA actuator and related methods. One embodiment of the actuator includes: a base; a plurality of buckle arms; and at least one first shape memory alloy wire coupled to one pair of buckle arms of the plurality of buckle arms. Another embodiment of the actuator includes a base and at least one dual piezoelectric chip actuator comprising a shape memory alloy material. The dual piezoelectric chip actuator is attached to the base.

[0004] Other features and advantages of embodiments of the present invention will become apparent from the accompanying drawings and the following detailed description. Simple Explanation of the Diagram

[0005] Embodiments of the invention are illustrated in the accompanying drawings by way of example and not limitation, wherein similar element symbols indicate similar elements and wherein:

[0006] Figure 1a illustrates a lens assembly comprising an SMA actuator configured as a buckle actuator according to one embodiment;

[0007] Figure 1b illustrates an SMA actuator according to one embodiment;

[0008] Figure 2 illustrates an SMA actuator according to one embodiment;

[0009] Figure 3 illustrates an exploded view of an autofocus assembly including an SMA line actuator according to one embodiment;

[0010] Figure 4 illustrates an autofocus assembly including an SMA actuator according to one embodiment;

[0011] Figure 5 illustrates an SMA actuator including a sensor according to one embodiment;

[0012] Figure 6 illustrates a top view and a side view of an SMA actuator configured as a buckle actuator according to one embodiment, the SMA actuator being equipped with a lens bracket;

[0013] Figure 7 illustrates a side view of a section of the SMA actuator according to this embodiment;

[0014] Figure 8 illustrates multiple views of one embodiment of a buckle actuator;

[0015] Figure 9 illustrates a dual piezoelectric crystal actuator with a lens holder according to one embodiment;

[0016] Figure 10 illustrates a cross-sectional view of an autofocus assembly including an SMA actuator according to one embodiment;

[0017] Figures 11a and 11c illustrate views of a dual piezoelectric chip actuator according to some embodiments;

[0018] Figure 12 illustrates a view of one embodiment of a dual piezoelectric chip actuator according to one embodiment;

[0019] Figure 13 illustrates a cross-section of one end pad of a dual piezoelectric wafer actuator according to one embodiment;

[0020] Figure 14 illustrates a cross-section of a central supply pad of a dual piezoelectric wafer actuator according to one embodiment;

[0021] Figure 15 illustrates an exploded view of an SMA actuator comprising one of two buckle actuators according to an embodiment;

[0022] Figure 16 illustrates an SMA actuator comprising one of two buckle actuators according to one embodiment;

[0023] Figure 17 illustrates a side view of an SMA actuator comprising one of two buckle actuators according to one embodiment;

[0024] Figure 18 illustrates a side view of an SMA actuator comprising one of two buckle actuators according to one embodiment;

[0025] Figure 19 illustrates an exploded view of an assembly including an SMA actuator according to one embodiment, the SMA actuator comprising two buckle actuators;

[0026] Figure 20 illustrates an SMA actuator comprising one of two buckle actuators according to one embodiment;

[0027] Figure 21 illustrates an SMA actuator comprising one of two buckle actuators according to one embodiment;

[0028] Figure 22 illustrates an SMA actuator comprising one of two buckle actuators according to one embodiment;

[0029] Figure 23 illustrates an SMA actuator according to one embodiment, comprising two buckle actuators and a coupler;

[0030] Figure 24 illustrates an exploded view of an SMA system according to one embodiment, which includes an SMA actuator comprising a buckle actuator having a single-layer press bed.

[0031] Figure 25 illustrates an SMA system according to one embodiment, which includes an SMA actuator comprising a buckle actuator 2402 having a laminated hammock.

[0032] Figure 26 illustrates a buckle actuator comprising a single-layer press hammock according to one embodiment;

[0033] Figure 27 illustrates a laminated hammock according to one embodiment of an SMA actuator;

[0034] Figure 28 illustrates a laminated press-fit connector according to one embodiment of an SMA actuator;

[0035] Figure 29 illustrates an SMA actuator comprising a single-layer press-fitted hammock with a buckle actuator;

[0036] Figure 30 illustrates an exploded view of an SMA system including an SMA actuator according to one embodiment, the SMA actuator including a buckle actuator;

[0037] Figure 31 illustrates an SMA system according to one embodiment, which includes an SMA actuator comprising a buckle actuator;

[0038] Figure 32 illustrates an SMA actuator including a buckle actuator according to one embodiment;

[0039] Figure 33 illustrates a double-yoke capture joint of a buckle arm in one embodiment of an SMA actuator;

[0040] Figure 34 illustrates a resistance-welded press-fit of an SMA actuator according to one embodiment, the SMA actuator being used to attach an SMA wire to a buckle actuator;

[0041] Figure 35 illustrates an SMA actuator comprising a buckle actuator with a double-yoke capture joint;

[0042] Figure 36 illustrates a liquid lens with SMA dual piezoelectric wafers according to one embodiment;

[0043] Figure 37 illustrates a perspective SMA dual piezoelectric crystal liquid lens according to one embodiment;

[0044] Figure 38 illustrates a cross-section and a bottom view of an SMA dual piezoelectric wafer liquid lens according to an embodiment;

[0045] Figure 39 illustrates an SMA system according to one embodiment, comprising an SMA actuator having one of dual piezoelectric chip actuators;

[0046] Figure 40 illustrates an SMA actuator with dual piezoelectric chip actuators according to one embodiment;

[0047] Figure 41 illustrates the length of a dual piezoelectric chip actuator and the position of an SMA wire extending beyond one of the bonding pads of the dual piezoelectric chip actuator;

[0048] Figure 42 illustrates an exploded view of an SMA system including a dual piezoelectric chip actuator according to one embodiment;

[0049] Figure 43 illustrates an exploded view of a subsection of an SMA actuator according to one embodiment;

[0050] Figure 44 illustrates a subsection of an SMA actuator according to one embodiment;

[0051] Figure 45 illustrates a 5-axis sensor shifting system according to one embodiment;

[0052] Figure 46 illustrates an exploded view of a 5-axis sensor shifting system according to one embodiment;

[0053] Figure 47 illustrates an SMA actuator, one of the dual piezoelectric chip actuators integrated into this circuit for all motions, according to one embodiment;

[0054] Figure 48 illustrates an SMA actuator, one of the dual piezoelectric chip actuators integrated into this circuit for all motions, according to one embodiment;

[0055] Figure 49 illustrates a cross-section of a 5-axis sensor shifting system according to one embodiment;

[0056] Figure 50 illustrates an SMA actuator comprising a dual piezoelectric chip actuator according to one embodiment;

[0057] Figure 51 illustrates a top view of an SMA actuator, one of a dual piezoelectric chip actuators comprising moving an image sensor at different x and y positions, according to an embodiment;

[0058] Figure 52 illustrates an SMA actuator, one of the dual piezoelectric wafer actuators, configured as a box-type dual piezoelectric wafer autofocusing device according to one embodiment;

[0059] Figure 53 illustrates an SMA actuator comprising a dual piezoelectric chip actuator according to one embodiment;

[0060] Figure 54 illustrates an SMA actuator comprising a dual piezoelectric chip actuator according to one embodiment;

[0061] Figure 55 illustrates an SMA actuator comprising a dual piezoelectric chip actuator according to one embodiment;

[0062] Figure 56 illustrates an SMA system according to one embodiment, which includes an SMA actuator comprising a dual piezoelectric chip actuator;

[0063] Figure 57 illustrates an exploded view of an SMA system including an SMA actuator according to one embodiment, the SMA actuator comprising a dual piezoelectric wafer actuator configured as a biaxial lens shift OIS;

[0064] Figure 58 illustrates a cross-section of an SMA system including an SMA actuator according to one embodiment, the SMA actuator comprising a dual piezoelectric wafer actuator configured as a biaxial lens shift OIS;

[0065] Figure 59 illustrates a cartridge-type dual piezoelectric chip actuator according to one embodiment;

[0066] Figure 60 illustrates an SMA system according to one embodiment, which includes an SMA actuator comprising a dual piezoelectric chip actuator;

[0067] Figure 61 illustrates an exploded view of an SMA system including an SMA actuator according to one embodiment, the SMA actuator comprising a dual piezoelectric chip actuator;

[0068] Figure 62 illustrates a cross-section of an SMA system including an SMA actuator according to one embodiment, the SMA actuator comprising a dual piezoelectric chip actuator;

[0069] Figure 63 illustrates a cartridge-type dual piezoelectric chip actuator according to one embodiment;

[0070] Figure 64 illustrates an SMA system according to one embodiment, which includes an SMA actuator comprising a dual piezoelectric chip actuator;

[0071] Figure 65 illustrates an exploded view of an SMA system including an SMA actuator according to one embodiment, the SMA actuator comprising a dual piezoelectric chip actuator;

[0072] Figure 66 illustrates an SMA system according to one embodiment, which includes an SMA actuator comprising a dual piezoelectric chip actuator;

[0073] Figure 67 illustrates an SMA system according to one embodiment, which includes an SMA actuator comprising a dual piezoelectric chip actuator;

[0074] Figure 68 illustrates an SMA system according to one embodiment, which includes an SMA actuator comprising a dual piezoelectric chip actuator;

[0075] Figure 69 illustrates an exploded view of an SMA including an SMA actuator according to one embodiment, the SMA actuator comprising a dual piezoelectric chip actuator;

[0076] Figure 70 illustrates a cross-section of an SMA system including an SMA actuator according to one embodiment, the SMA actuator comprising a dual piezoelectric chip actuator configured as a 3-axis sensor shift OIS;

[0077] Figure 71 illustrates a cartridge-type dual piezoelectric chip actuator assembly according to one embodiment;

[0078] Figure 72 illustrates a flexible sensor circuit for use in an SMA system according to one embodiment;

[0079] Figure 73 illustrates an SMA system according to one embodiment, which includes an SMA actuator comprising a dual piezoelectric chip actuator;

[0080] Figure 74 illustrates an exploded view of an SMA system including an SMA actuator according to one embodiment, the SMA actuator comprising a dual piezoelectric chip actuator;

[0081] Figure 75 illustrates a cross-section of an SMA system including an SMA actuator according to one embodiment;

[0082] Figure 76 illustrates a cartridge-type dual piezoelectric chip actuator according to one embodiment;

[0083] Figure 77 illustrates a flexible sensor circuit for use in an SMA system according to one embodiment;

[0084] Figure 78 illustrates an SMA system according to one embodiment, which includes an SMA actuator comprising a dual piezoelectric chip actuator;

[0085] Figure 79 illustrates an exploded view of an SMA system including an SMA actuator according to one embodiment, the SMA actuator comprising a dual piezoelectric chip actuator;

[0086] Figure 80 illustrates a cross-section of an SMA system including an SMA actuator according to one embodiment;

[0087] Figure 81 illustrates a cartridge-type dual piezoelectric chip actuator according to one embodiment;

[0088] Figure 82 illustrates a flexible sensor circuit for use in an SMA system according to one embodiment;

[0089] Figure 83 illustrates an SMA system according to one embodiment, which includes an SMA actuator comprising a dual piezoelectric chip actuator;

[0090] Figure 84 illustrates an exploded view of an SMA system including an SMA actuator according to one embodiment;

[0091] Figure 85 illustrates a cross-section of an SMA system including an SMA actuator according to one embodiment, the SMA actuator comprising a dual piezoelectric chip actuator;

[0092] Figure 86 illustrates a cartridge-type dual piezoelectric chip actuator for use in an SMA system according to one embodiment;

[0093] Figure 87 illustrates a flexible sensor circuit for use in an SMA system according to one embodiment;

[0094] Figure 88 illustrates exemplary dimensions of a dual piezoelectric chip actuator according to one embodiment of the SMA actuator;

[0095] Figure 89 illustrates a lens system for a folding camera according to one embodiment;

[0096] Figure 90 illustrates several embodiments of a lens system including a liquid lens according to one embodiment;

[0097] Figure 91 illustrates a folding lens, as a prism, mounted on a actuator according to one embodiment;

[0098] Figure 92 illustrates a dual piezoelectric wafer arm with an offset according to one embodiment;

[0099] Figure 93 illustrates a dual piezoelectric wafer arm having an offset and a limiter according to one embodiment;

[0100] Figure 94 illustrates a dual piezoelectric wafer arm having an offset and a limiter according to one embodiment;

[0101] Figure 95 illustrates one embodiment of a base including a dual piezoelectric wafer arm with one offset, according to one embodiment;

[0102] Figure 96 illustrates one embodiment of a base comprising two offset dual piezoelectric wafer arms according to one embodiment;

[0103] Figure 97 illustrates a buckle arm including a load point extension according to one embodiment;

[0104] Figure 98 illustrates a buckle arm 9801 including a load point extension 9810 according to one embodiment;

[0105] Figure 99 illustrates a dual piezoelectric wafer arm including a load point extension according to one embodiment;

[0106] Figure 100 illustrates a dual piezoelectric wafer arm including a load point extension according to one embodiment;

[0107] Figure 101 illustrates an SMA optical image stabilizer according to one embodiment;

[0108] Figure 102 illustrates an SMA material attachment portion 40 of a movable part according to one embodiment;

[0109] Figure 103 illustrates an SMA attachment portion of a static plate according to one embodiment, wherein resistance-welded SMA wires are attached to the SMA attachment portion;

[0110] Figure 104 illustrates an SMA actuator 45 including a buckle actuator according to one embodiment;

[0111] Figures 105a and 105b illustrate a resistance-welded press-fit comprising an island for an SMA actuator according to one embodiment;

[0112] Figure 106 illustrates the relationship between the bending plane z-offset, the slot width, and the peak force of a double piezoelectric wafer beam according to one embodiment;

[0113] Figure 107 illustrates an example of how the volume of a box, which is an approximation of a box surrounding the entire dual piezoelectric chip actuator, relates to the power of each dual piezoelectric chip assembly according to one embodiment;

[0114] Figure 108 illustrates a liquid lens actuated using a buckle actuator according to one embodiment;

[0115] Figure 109 illustrates one of the unfixed, load-point ends of a dual piezoelectric wafer arm according to one embodiment;

[0116] Figure 110 illustrates one of the unfixed, load-point ends of a dual piezoelectric wafer arm according to one embodiment;

[0117] Figure 111 illustrates one of the unfixed, load-point ends of a dual piezoelectric wafer arm according to one embodiment;

[0118] Figure 112 illustrates one of the unfixed, load-point ends of a dual piezoelectric wafer arm according to one embodiment;

[0119] Figure 113 illustrates a fixed end of one of the dual piezoelectric wafer arms according to one embodiment;

[0120] Figure 114 illustrates a fixed end of one of the dual piezoelectric wafer arms according to one embodiment;

[0121] Figure 115 illustrates a fixed end of one of the dual piezoelectric wafer arms according to one embodiment;

[0122] Figure 116 illustrates a fixed end of one of the dual piezoelectric wafer arms according to one embodiment;

[0123] Figure 117 illustrates a rear view of one of the fixed ends of a dual piezoelectric wafer arm according to one embodiment;

[0124] Figure 118 illustrates one of the unfixed, load-point ends of a dual piezoelectric wafer arm according to one embodiment;

[0125] Figure 119 illustrates an unfixed, load-point end of one of the dual piezoelectric wafer arms according to one of an alternative embodiments;

[0126] Figure 120 illustrates an unfixed, load-point end of one of the dual piezoelectric wafer arms according to one of an alternative embodiments;

[0127] Figure 121 illustrates an unfixed, load-point end of one of the dual piezoelectric wafer arms according to one of an alternative embodiments;

[0128] Figure 122 illustrates the unfixed, load point end of one of the dual piezoelectric wafer arms according to one of an alternative embodiments;

[0129] Figure 123 illustrates a fixed end of one of the dual piezoelectric wafer arms according to one embodiment;

[0130] Figure 124 illustrates a fixed end of one of the dual piezoelectric wafer arms according to one embodiment;

[0131] Figure 125 illustrates a fixed end of one of the dual piezoelectric wafer arms according to one embodiment;

[0132] Figure 126 illustrates a balanced dual piezoelectric crystal actuator according to one embodiment, comprising one of two dual piezoelectric crystal arms arranged in an interleaved orientation;

[0133] Figure 127 illustrates an optical image stabilization system including a balanced dual piezoelectric chip actuator according to one embodiment;

[0134] Figure 128 illustrates a balanced dual piezoelectric crystal actuator according to one embodiment, comprising one of two dual piezoelectric crystal arms arranged in a linear orientation.

[0135] Figure 129 illustrates a top view of a balanced dual piezoelectric crystal actuator according to an embodiment, comprising one of two dual piezoelectric crystal arms arranged in a linear orientation.

[0136] Figure 130 illustrates a top view of a balanced dual piezoelectric chip actuator comprising a common base island according to one embodiment;

[0137] Figure 131 illustrates a side view of a balanced dual piezoelectric crystal actuator according to an embodiment, comprising two dual piezoelectric crystal arms arranged in a reverse in-line orientation;

[0138] Figure 132 illustrates a top view of a balanced dual piezoelectric crystal actuator according to an embodiment, comprising two dual piezoelectric crystal arms arranged in a reverse in-line orientation;

[0139] Figure 133 illustrates a top view of a balanced dual piezoelectric crystal actuator according to an embodiment, comprising two dual piezoelectric crystal arms arranged in a reverse in-line orientation;

[0140] Figure 134 illustrates a balanced dual piezoelectric crystal actuator according to one embodiment, comprising one of two dual piezoelectric crystal arms arranged in a linear orientation.

[0141] Figure 135 illustrates a top view of a balanced dual piezoelectric crystal actuator according to an embodiment, comprising two dual piezoelectric crystal arms arranged in a linear orientation.

[0142] Figure 136 illustrates a top view of a balanced dual piezoelectric crystal actuator according to an embodiment, comprising two dual piezoelectric crystal arms arranged in a linear orientation.

[0143] Figure 137 illustrates a balanced dual piezoelectric crystal actuator according to one embodiment, comprising one of two dual piezoelectric crystal arms arranged in an interleaved orientation;

[0144] Figure 138 illustrates a top view of a balanced dual piezoelectric crystal actuator according to an embodiment, comprising two dual piezoelectric crystal arms arranged in an interleaved orientation;

[0145] Figure 139 illustrates a top view of a balanced dual piezoelectric crystal actuator according to an embodiment, comprising two dual piezoelectric crystal arms arranged in an interleaved orientation;

[0146] Figure 140 illustrates an optical image stabilization system including a balanced dual piezoelectric chip actuator according to one embodiment;

[0147] Figure 141 illustrates an exploded view of an optical image stabilization system including a balanced dual piezoelectric chip actuator according to one embodiment;

[0148] Figure 142 illustrates an optical image stabilization system including a balanced dual piezoelectric chip actuator according to one embodiment;

[0149] Figure 143 illustrates a sensor-shift optical image stabilization system including one of two piezoelectric chip actuators according to one embodiment;

[0150] Figure 144 illustrates an optical image stabilization system including a balanced dual piezoelectric chip actuator according to one embodiment;

[0151] Figure 145 illustrates the housing of an optical image stabilization system according to one embodiment;

[0152] Figure 146 illustrates a cross-section of an optical image stabilization system including a housing according to one embodiment;

[0153] Figure 147 illustrates an exploded view of an optical image stabilization system including a leaf spring circuit according to one embodiment;

[0154] Figure 148 illustrates a cross-section of an optical image stabilization system including a leaf spring circuit according to one embodiment;

[0155] Figure 149 illustrates a base including a spring according to one embodiment;

[0156] Figure 150 illustrates a leaf spring circuit according to one embodiment; and

[0157] Figure 151 illustrates a dual piezoelectric chip actuator including a press-fit according to one embodiment. Implementation

[0158] Cross-reference to related applications This application claims the benefit of U.S. Provisional Patent Application No. 63 / 152,299, filed February 22, 2021, and U.S. Patent Application No. 17 / 569,268, filed January 5, 2022, the entire contents of which are incorporated herein by reference.

[0159] This document describes an embodiment of an SMA actuator that includes a compact coverage area and provides a high actuation height, such as movement in the positive z-axis direction (z-direction), referred to herein as the z-stroke. The embodiment of the SMA actuator includes an SMA buckle actuator and an SMA dual piezoelectric chip actuator. SMA actuators can be used in a variety of applications (including, but not limited to, lens assemblies as autofocus actuators, microfluidic pumps, sensor shifting, optical image stabilization, and optical zoom assemblies) to mechanically strike two surfaces to produce a tactile feedback sensation commonly found in haptic feedback sensors and devices, and other systems in which actuators are used. For example, the embodiment of the actuator described herein can be used as a haptic feedback actuator in a mobile phone or wearable device configured to provide a user with an alarm, notification, warning, touch area, or button press response. Furthermore, more than one SMA actuator can be used in a system to achieve a greater stroke.

[0160] In various embodiments, the SMA actuator has a z-stroke greater than 0.4 mm. Furthermore, in various embodiments, when the SMA actuator is in its initial, non-actuated position, the SMA actuator has a height of 2.2 mm or less in the z-direction. Embodiments of an SMA actuator configured as an autofocusing actuator in a lens assembly may have a coverage area only 3 mm larger than the lens inner diameter ("ID"). According to various embodiments, the SMA actuator may have a coverage area wider in one direction to accommodate components including, but not limited to, sensors, wires, traces, and connectors. According to some embodiments, the coverage area of ​​an SMA actuator is 0.5 mm larger in one direction; for example, the length of the SMA actuator is 0.5 mm larger than its width.

[0161] Figure 1a illustrates a lens assembly comprising an SMA actuator configured as a buckle actuator according to one embodiment. Figure 1b illustrates an SMA actuator configured as a buckle actuator according to one embodiment. The buckle actuator 102 is coupled to a base 101. As illustrated in Figure 1b, an SMA wire 100 is attached to the buckle actuator 102 such that when the SMA wire 100 is actuated and retracted, this causes the buckle actuator 102 to engage, resulting in at least the central portion 104 of each buckle actuator 102 moving in the z-stroke direction (e.g., the positive z-direction), as indicated by arrow 108. According to some embodiments, the wire is actuated when current is supplied to one end of the SMA wire 100 through a wire holder such as a crimp structure 106. Current flows through the SMA wire 100, thereby heating the SMA wire 100 due to the inherent resistance of the SMA material in which the SMA wire 100 is made. On the other side of the SMA wire 100 is a wire retainer, such as a crimp structure 106 connecting the SMA wire 100 to ground the circuit. Heating the SMA wire 100 to a sufficient temperature causes the unique material properties to change from a martensitic to an austenitic crystal structure, resulting in a change in the length of the wire. Changing the current changes the temperature and therefore the length of the wire, which is used to actuate and deactuate the actuator to control its movement in at least the z-direction. Those skilled in the art will understand that other techniques can be used to supply current to an SMA wire.

[0162] Figure 2 illustrates an SMA actuator configured as an SMA dual piezoelectric chip actuator according to one embodiment. As shown in Figure 2, the SMA actuator includes a dual piezoelectric chip actuator 202 coupled to a base 204. The dual piezoelectric chip actuator 202 includes an SMA band 206. The dual piezoelectric chip actuator 202 is configured to move at least one unfixed end of the dual piezoelectric chip actuator 202 in the z-stroke direction 208 as the SMA band 206 contracts.

[0163] Figure 3 illustrates an exploded view of an autofocus assembly including an SMA actuator according to one embodiment. As shown, an SMA actuator 302 is configured as a buckle actuator according to one embodiment described herein. The autofocus assembly also includes an optical image stabilizer ("OIS") 304, a lens holder 306 configured to hold one or more optical lenses using techniques including those known in the art, a return spring 308, a vertical sliding bearing 310, and a guide cap 312. When the SMA is actuated using techniques including those described herein and pulls and holds the buckle actuator 302, the lens holder 306 is configured to slide against the vertical sliding bearing 310 as the SMA actuator 302 moves in the z-stroke direction (e.g., the positive z-axis direction). The return spring 308 is configured to apply a force on the lens holder 306 in a direction opposite to the z-stroke direction using techniques including those known in the art. According to various embodiments, the return spring 308 is configured to move the lens holder 306 in the opposite direction of the z-stroke direction when the tension in the SMA line decreases as the actuation of the SMA line is removed. When the tension in the SMA line decreases to its initial value, the lens holder 306 moves to its lowest height in the z-stroke direction. Figure 4 illustrates an autofocus assembly including an SMA line actuator according to one embodiment illustrated in Figure 3.

[0164] Figure 5 illustrates an SMA line actuator including a sensor according to one embodiment. For various embodiments, sensor 502 is configured to measure the movement of the SMA actuator in the z-direction or the movement of a component in which the SMA actuator is moving, using techniques including those known in the art. The SMA actuator includes one or more buckle actuators 506 configured to be actuated using one or more SMA lines 508 similar to those described herein. For example, in the autofocus assembly described with reference to Figure 4, the sensor is configured to determine the amount of movement of the lens holder 306 in the z-direction 504 from an initial position using techniques including those known in the art. According to some embodiments, the sensor is a tunnel magnetoresistive ("TMR") sensor.

[0165] Figure 6 illustrates a top view and a side view of an SMA actuator 602 configured as a buckle actuator according to one embodiment, wherein the SMA actuator 602 is equipped with a lens holder 604. Figure 7 illustrates a side view of a section of the SMA actuator 602 according to the embodiment illustrated in Figure 6. According to the embodiment illustrated in Figure 7, the SMA actuator 602 includes a sliding base 702. According to one embodiment, the sliding base 702 is formed of a metal such as stainless steel using techniques known in the art. However, those skilled in the art will understand that other materials can be used to form the sliding base 702. Furthermore, according to some embodiments, the sliding base 702 has a spring arm 612 coupled to the SMA actuator 602. According to various embodiments, the spring arm 612 is configured to serve two functions. The first function is to assist in pushing an object, such as a lens holder 604, into the vertical sliding surface of a guide cover. In this example, the spring arm 612 abuts against this surface to preload the lens holder 604 upwards to ensure that the lens will not tilt during actuation. In some embodiments, the vertical sliding surface 708 is configured to mate with the guide cover. A second function of the spring arm 612 is to assist in pulling the SMA actuator 602 downwards, for example, in the negative z-direction, after the SMA line 608 moves the SMA actuator 602 in the z-stroke direction (i.e., the positive z-direction). Therefore, when the SMA line 608 is actuated, it contracts to move the SMA actuator 602 in the z-stroke direction, and when the SMA line is de-actuated, the spring arm 612 is configured to move the SMA actuator 602 in the opposite direction of the z-stroke direction.

[0166] SMA actuator 602 also includes a buckle actuator 710. In various embodiments, the buckle actuator 710 is formed of a metal such as stainless steel. Furthermore, the buckle actuator 710 includes a buckle arm 610 and one or more wire retainers 606. According to the embodiments illustrated in Figures 6 and 7, the buckle actuator 710 includes four wire retainers 606. Each of the four wire retainers 606 is configured to receive and hold one end of an SMA wire 608, such that the SMA wire 608 is attached to the buckle actuator 710. In various embodiments, the four wire retainers 606 are crimps, configured to clamp downwards onto a portion of the SMA wire 608 to attach the wire to the crimp. Those skilled in the art will understand that the SMA wire 608 can be attached to a single wire retainer 606 using techniques known in the art, including but not limited to adhesives, solders, and mechanical attachments. A smart shape memory alloy (“SMA”) wire 608 extends between a pair of wire retainers 606, such that the buckle arm 610 of the buckle actuator 710 is configured to move when the SMA wire 608 is actuated, causing the pair of wire retainers 606 to be pulled closer together. According to various embodiments, when a current is applied to the SMA wire 608, the SMA wire 608 is electrically actuated to move and control the position of the buckle arm 610. When the current is removed or falls below a threshold value, actuation of the SMA wire 608 is deactivated. This removes the pair of wire retainers 606 and the buckle arm 610 moves in the opposite direction to when the SMA wire 608 was actuated. According to various embodiments, when the SMA wire is deactivated from its initial position, the buckle arm 610 is configured to have an initial angle of 5 degrees relative to the sliding base 702. Furthermore, according to various embodiments, during the full stroke or when the SMA line is fully actuated, the buckle arm 610 is configured to have an angle of 10 to 12 degrees relative to the sliding base 702.

[0167] According to the embodiments illustrated in Figures 6 and 7, the SMA actuator 602 also includes a sliding bearing 706 configured between the sliding base 702 and the wire retainer 606. The sliding bearing 706 is configured to minimize any friction between the sliding base 702 and a buckle arm 610 and / or the wire retainer 606. In some embodiments, the sliding bearing is attached to the wire retainer 606. According to various embodiments, the sliding bearing is formed of polyoxymethylene ("POM"). Those skilled in the art will understand that other structures can be used to reduce any friction between the buckle actuator and the base.

[0168] According to various embodiments, the sliding base 702 is configured to couple with an assembly base 704, such as an autofocusing assembly. According to some embodiments, the actuator base 704 includes an etched pad. When the SMA actuator 602 is part of an assembly such as an autofocusing assembly, this etched pad can be used to provide clearance for the wire and crimp.

[0169] Figure 8 illustrates multiple views of one embodiment of a buckle actuator 802 relative to an x-axis, a y-axis, and a z-axis. Oriented as shown in Figure 8, the buckle arm 804 is configured to move along the z-axis when the SMA line is actuated and de-actuated as described herein. According to the embodiment illustrated in Figure 8, the buckle arms 804 are coupled to each other via a central portion such as a hammock portion 806. According to various embodiments, the hammock portion 806 is configured to support a portion of an object acted upon by the buckle actuator (e.g., a lens holder moved by the buckle actuator using techniques including those described herein). According to some embodiments, the hammock portion 806 is configured to provide lateral rigidity to the buckle actuator during actuation. For other embodiments, a buckle actuator does not include a hammock portion 806. According to these embodiments, the buckle arms are configured to act on an object to move the object. For example, a buckle arm is configured to act directly on a feature of a lens holder to push the lens holder upward.

[0170] Figure 9 illustrates one of the SMA actuators configured as an SMA dual piezoelectric chip actuator according to one embodiment. The SMA dual piezoelectric chip actuator includes a dual piezoelectric chip actuator 902, which includes the dual piezoelectric chip actuator described herein. According to the embodiment illustrated in Figure 9, one end 906 of each of the dual piezoelectric chip actuators 902 is attached to a base 908. According to some embodiments, this end 906 is soldered to the base 908. However, those skilled in the art will understand that another technique can be used to attach this end 906 to the base 908. Figure 9 also illustrates a lens holder 904 configured such that the dual piezoelectric chip actuator 902 is configured to curl in the z-direction and lift the holder 904 in the z-axis direction when actuated. For some embodiments, a return spring is used to push the dual piezoelectric chip actuator 902 back to an initial position. A reset spring can be configured as described herein to assist in pushing the dual piezoelectric crystal actuator down to its initial and deactivated actuation positions. Due to the small coverage area of ​​the dual piezoelectric crystal actuator, an SMA actuator with a reduced coverage area can be fabricated compared to current actuator technology.

[0171] Figure 10 illustrates a cross-sectional view of an autofocus assembly including an SMA actuator according to one embodiment, the SMA actuator including a position sensor, such as a TMR sensor. The autofocus assembly 1002 includes a position sensor 1004 attached to a movement spring 1006, and a magnet 1008 attached to a lens holder 1010 of an autofocus assembly including an SMA actuator such as those described herein. The position sensor 1004 is configured to determine the amount of movement of the lens holder 1010 from an initial position in the z-direction 1005 based on a distance from the magnet 1008 to the position sensor 1004 using techniques including those known in the art. According to some embodiments, the position sensor 1004 is electrically coupled to a controller or a processor (such as a central processing unit) using a plurality of traces on a spring arm of a movement spring 1006 of an optical image stabilization assembly.

[0172] Figures 11a and 11c illustrate views of dual piezoelectric wafer actuators according to various embodiments. According to various embodiments, a dual piezoelectric wafer actuator 1102 includes a beam 1104 and one or more SMA materials 1106b, such as an SMA strip 1106b (e.g., illustrated in a perspective view of a dual piezoelectric wafer actuator including an SMA strip according to the embodiment of Figure 11b) or an SMA line (e.g., illustrated in a cross-section of a dual piezoelectric wafer actuator including an SMA line according to the embodiment of Figure 11a). The SMA material 1106b is attached to the beam 1104 using techniques incorporating those described herein. According to some embodiments, the SMA material 1106b is attached to the beam 1104 using an adhesive film material 1108. In various embodiments, the ends of the SMA material 1106b are electrically and mechanically coupled to contact 1110, which is configured to supply current to the SMA material 1106b using techniques including those known in the art. According to various embodiments, contact 1110 (e.g., as illustrated in Figures 11a and 11b) is a gold-plated copper pad. According to an embodiment, a dual piezoelectric crystal actuator 1102 having a length of approximately 1 mm is configured to generate a large stroke and a thrust of 50 millinewtons (mN) as part of a lens assembly, for example, as illustrated in Figure 11c. According to some embodiments, the use of a dual piezoelectric crystal actuator 1102 having a length greater than 1 mm will generate a larger stroke but less force than a dual piezoelectric crystal actuator having a length of 1 mm. In one embodiment, a dual piezoelectric wafer actuator 1102 includes a 20-micron-thick SMA material 1106b, a 20-micron-thick insulator 1112 (such as a polyimide insulator), and a 30-micron-thick stainless steel beam 1104 or alkali metal. Various embodiments include a second insulator disposed between a contact layer including a contact 1110 and the SMA material 1106b. According to some embodiments, the second insulator is configured to insulate the SMA material 1106b from portions of the contact layer not used as contact 1110. In some embodiments, the second insulation is a surface coating, such as a polyimide insulator. Those skilled in the art will understand that other sizes and materials can be used to meet the desired design characteristics.

[0173] Figure 12 illustrates a view of one embodiment of a dual piezoelectric chip actuator according to one embodiment. The embodiment illustrated in Figure 12 includes a central feed 1204 for applying power. Power is supplied at the center of an SMA material 1202 (wire or strip) (such as an SMA material described herein). The end of the SMA material 1202 is grounded at an end pad 1203 as a return path to a beam 1206 or alkali metal. The end pad 1203 is electrically isolated from the remainder of the contact layer 1214. According to the embodiment, a beam 1206 or alkali metal extremely close to the SMA material 1202 (such as an SMA wire) along the entire length of the SMA material 1202 provides faster wire cooling when the current is turned off (i.e., the dual piezoelectric chip actuator is de-actuated). The result is a faster wire de-start and actuator response time. The thermal distribution of the SMA wire or strip is improved. For example, a more uniform thermal distribution allows a higher total current to be reliably delivered to the wire. Without a uniform heat sink, portions of the wire (such as a central area) may overheat and become damaged, thus requiring reduced current and movement for reliable operation. The center feed 1204 provides the SMA material 1202 with the benefits of faster wire start-up / actuation (faster heating) and reduced power consumption (shorter resistance path length) resulting in a faster response time. This allows for faster actuator movement and the ability to operate at a higher frequency.

[0174] As illustrated in Figure 12, beam 1206 includes a central metal 1208 isolated from the rest of beam 1206 to form a central feed 1204. An insulator 1210, such as the insulator described herein, is disposed above beam 1206. Insulator 1210 is configured to have one or more openings or through-holes 1212 to provide electrical pathways to beam 1206, for example, to couple a contact layer of a grounding section 1214b, and to provide contact with the central metal 1208 to form the central feed 1204. According to some embodiments, a contact layer 1214 (such as the contact layer described herein) includes a power section 1214a and a grounding section 1214b to provide actuation / control signals to a dual piezoelectric chip actuator via a power supply contact 1216 and a grounding contact 1218. A coating 1220 (such as the coating described herein) is disposed over the contact layer 1214 to electrically isolate the contact layer, except at the portion of the contact layer 1214 where the electrical coupling system is desired to be coupled (e.g., one or more contacts).

[0175] Figure 13 illustrates a cross-section of one end pad of a dual piezoelectric chip actuator according to one embodiment illustrated in Figure 12. As described above, the end pad 1203 is electrically isolated from the remainder of the contact layer 1214 by a gap 1222 formed between the end pad 1203 and the contact layer 1214. According to some embodiments, the gap is formed using an etching technique including etching techniques known in the art. The end pad 1203 includes a via section 1224 configured to electrically couple the end pad 1203 to the beam 1206. The via section 1224 is formed in a via 1212 formed in the insulator 1210. SMA material 1202 is electrically coupled to the end pad 1203. The SMA material 1202 can be electrically coupled to the end pad 1203 using techniques including, but not limited to, soldering, resistance soldering, laser soldering, and direct electroplating.

[0176] Figure 14 illustrates a cross-section of a center-fed actuator according to one embodiment of the dual piezoelectric chip actuator shown in Figure 12. The center-fed 1204 is electrically coupled to a power supply through a contact layer 1214 and electrically and thermally coupled to a central metal 1208 through a via segment 1224 in the center-fed 1204, the via segment 1224 being formed in a via 1212 in an insulator 1210.

[0177] The actuators described herein can be used to form an actuator assembly employing multiple buckles and / or multiple dual piezoelectric chip actuators. According to one embodiment, these actuators can be stacked on top of each other to increase the achievable stroke distance.

[0178] Figure 15 illustrates an exploded view of an SMA actuator comprising one of two buckle actuators according to one embodiment. According to the embodiments described herein, the two buckle actuators 1302, 1304 are configured relative to each other to use their equal motion relative to each other. For various embodiments, the two buckle actuators 1302, 1304 are configured to move in an inverse relationship to position a lens holder 1306. For example, the first buckle actuator 1302 is configured to receive an inverse electrical signal transmitted to one of the electrical signals of the second buckle actuator 1304.

[0179] Figure 16 illustrates an SMA actuator comprising two buckle actuators according to one embodiment. Buckle actuators 1302 and 1304 are configured such that the buckle arms 1310 and 1312 of each buckle actuator 1302 and 1304 face each other, and the sliding bases 1314 and 1316 of each buckle actuator 1302 and 1304 are one of the outer surfaces of the two buckle actuators. According to various embodiments, a hammock portion 1308 of each SMA actuator 1302 and 1304 is configured to support a portion of an object acted upon by one or more buckle actuators 1302 and 1304 (e.g., a lens holder 1306 moved by the buckle actuators using techniques including those described herein).

[0180] Figure 17 illustrates a side view of an SMA actuator comprising one of two buckle actuators according to an embodiment, showing the direction of the SMA line 1318 that causes movement of an object such as a lens holder in a positive z-direction or an upward direction.

[0181] Figure 18 illustrates a side view of an SMA actuator comprising one of two buckle actuators according to an embodiment, showing the direction of the SMA line 1318 that causes movement of an object such as a lens holder in a negative z-direction or in a downward direction.

[0182] Figure 19 illustrates an exploded view of an assembly including an SMA actuator according to one embodiment, the SMA actuator comprising two buckle actuators. Buckle actuators 1902 and 1904 are configured such that buckle arms 1910 and 1912 of each buckle actuator 1902 and 1904 are attached to one of the outer surfaces of the two buckle actuators, and sliding bases 1914 and 1916 of each buckle actuator 1902 and 1904 face each other. According to various embodiments, a hammock portion 1908 of each SMA actuator 1902 and 1904 is configured to support a portion of an object acted upon by one or more buckle actuators 1902 and 1904 (e.g., a lens holder 1906 moved by the buckle actuators using techniques including those described herein). In some embodiments, the SMA actuator includes a base portion 1918 configured to receive a second buckle actuator 1904. The SMA actuator may also include a cover portion 1920. Figure 20 illustrates an SMA actuator according to one embodiment that includes two buckle actuators, the SMA actuator including a base portion and a cover portion.

[0183] Figure 21 illustrates an SMA actuator comprising one of two buckle actuators according to one embodiment. In some embodiments, buckle actuators 1902 and 1904 are configured relative to each other such that the hammock portion 1908 of the first buckle actuator 1902 rotates approximately 90 degrees from the hammock portion of the second buckle actuator 1904. This 90-degree configuration enables pitch and roll rotation of an object, such as a lens holder 1906. This provides better control over the movement of the lens holder 1906. In various embodiments, differential electrical signals are applied to the SMA lines of each buckle actuator pair, which provides pitch and roll rotation of the lens holder for tilt OIS motion.

[0184] Embodiments of SMA actuators incorporating two buckle actuators eliminate the need for a return spring. When using SMA line resistance for position feedback, the use of two buckle actuators improves / reduces hysteresis. Compared to SMA actuators with a return spring, SMA actuators with two buckle actuators contribute to more accurate position control due to lower hysteresis. For some embodiments, such as the one illustrated in Figure 22, the SMA actuators incorporating two buckle actuators 2202, 2204 use differential power to provide two-axis tilting to the left SMA line 2218a and right SMA line 2218b of each buckle actuator 2202, 2204. For example, a left SMA line 2218a is actuated with a higher power than a right SMA line 2218b. This causes the left side of the lens holder 2206 to move downwards and the right side to move upwards (tilt). In some embodiments, the SMA lines of the first buckle actuator 2202 are kept at equal power to act as a fulcrum for differentially actuating the SMA lines 2218a, 2218b to cause tilting movement. Reversing the power signal applied to the SMA lines, for example, applying equal power to the SMA lines of the second buckle actuator 2204 and applying differential power to the left SMA lines 2218a and right SMA lines 2218b of the second buckle actuator 2204, causes the lens holder 2206 to tilt in one of the other directions. This provides the ability to tilt an object such as a lens holder on either axis of motion, or to detune any tilt between the lens and the sensor to obtain good dynamic tilt, which results in better image quality across all pixels.

[0185] Figure 23 illustrates an SMA actuator according to one embodiment, comprising two buckle actuators and a coupler. The SMA actuator comprises two buckle actuators, such as those described herein. A first buckle actuator 2302 is configured to be coupled to a second buckle actuator 2304 using a coupler such as a coupler ring 2305. Buckle actuators 2302 and 2304 are configured relative to each other such that the hammock portion 2308 of the first buckle actuator 2302 rotates approximately 90 degrees from the hammock portion 2309 of the second buckle actuator 2304. A payload (such as a lens or lens assembly) for movement is attached to a lens holder 2306 configured to be mounted on a sliding base of the first buckle actuator 2302.

[0186] In various embodiments, equal electrical current can be applied to the SMA lines of the first buckle actuator 2302 and the second buckle actuator 2304. This results in maximizing the z-stroke of the SMA actuator in the positive z-direction. In some embodiments, the stroke of the SMA actuator may have a z-stroke equal to or greater than twice the stroke of another SMA actuator comprising two buckle actuators. In some embodiments, when the electrical signal is removed from the SMA actuator, an additional spring can be added to push against the two buckle actuators to assist in pushing the actuator assembly and the payload downward. The same and opposite electrical signals can be applied to the SMA lines of the first buckle actuator 2302 and the second buckle actuator 2304. This allows the SMA actuator to move in the positive z-axis direction by one buckle actuator and in the negative z-direction by another buckle actuator, thus achieving accurate position control of the SMA actuator. In addition, equal and opposite electrical signals (differential electrical signals) can be applied to the left and right SMA lines of the first buckle actuator 2302 and the second buckle actuator 2304 to tilt an object such as a lens holder 2306 on at least one of the two axes.

[0187] An embodiment of an SMA actuator (such as the SMA actuator illustrated in Figure 23) comprising two buckle actuators and a coupler can be coupled with an additional buckle actuator and a buckle actuator to achieve a desired stroke greater than that of a single SMA actuator.

[0188] Figure 24 illustrates an exploded view of an SMA system including an SMA actuator according to one embodiment, the SMA actuator comprising a buckle actuator having a single layer of pressurized hammock. As described herein, for some embodiments, the SMA system is configured to be used in conjunction with one or more camera lens elements as an autofocus actuator. As illustrated in Figure 24, the SMA system includes a return spring 2403, configured according to various embodiments to move a lens holder 2405 in the opposite direction in the z-direction when the tension in the SMA line 2408 decreases as the actuation of the SMA line is deactivated. For some embodiments, the SMA system includes a housing 2409 configured to receive the return spring 2403 and act on a sliding bearing to guide the lens holder in the z-stroke direction. The housing 2409 is also configured to be mounted on a buckle actuator 2402. The buckle actuator 2402 includes a sliding base 2401 similar to a sliding base described herein. The buckle actuator 2402 includes a buckle arm 2404 coupled to a hammock portion (such as a laminated hammock 2406 formed of a laminate). The buckle actuator 2402 also includes an SMA wire attachment structure, such as a laminated crimp connector 2412.

[0189] As illustrated in Figure 24, a sliding base 2401 is mounted on an optional adapter plate 2414. This adapter plate is configured to allow the SMA system or buckle actuator 2402 to engage with another system (such as an OIS, an additional SMA system, or other components). Figure 25 illustrates an SMA system 2501 according to one embodiment, which includes an SMA actuator comprising a buckle actuator 2402 having a single layer of pressurized hammock.

[0190] Figure 26 illustrates a buckle actuator comprising a laminated hammock according to one embodiment. The buckle actuator 2402 includes a buckle arm 2404. The buckle arm 2404 is configured to move along the z-axis when the SMA line 2408 is actuated and de-actuated as described herein. The SMA line 2408 is attached to the buckle actuator using a laminated press-fit connector 2412. According to the embodiment illustrated in Figure 26, the buckle arms 2404 are coupled to each other via a central portion such as a laminated hammock 2406. According to various embodiments, the laminated hammock 2406 is configured to support a portion of an object acted upon by the buckle actuator (e.g., a lens holder moved by the buckle actuator using techniques including those described herein).

[0191] Figure 27 illustrates a laminated hammock according to one embodiment of an SMA actuator. In some embodiments, the laminated hammock 2406 is made of a low-rigidity material and therefore does not resist actuation movement. For example, the laminated hammock 2406 is formed using a copper layer disposed on a first polyimide layer and a second polyimide layer disposed on the copper. In some embodiments, the laminated hammock 2406 is formed on the buckle arm 2404 using deposition and etching techniques including those known in the art. In other embodiments, the laminated hammock 2406 is formed independently of the buckle arm 2404 and is attached to the buckle arm 2404 using techniques including welding, adhesives, and other techniques known in the art. In various embodiments, glue or other adhesives are used on the laminated hammock 2406 to ensure that the buckle arm 2404 remains in a position relative to a lens holder.

[0192] Figure 28 illustrates a laminated crimp connector for an SMA actuator according to one embodiment. The laminated crimp connector 2412 is configured to attach an SMA wire 2408 to a buckle actuator and, together with the SMA wire 2408, create a circuit connector. For various embodiments, the laminated crimp connector 2412 comprises a laminate formed of one or more layers of an insulator and one or more layers of conductive layers formed on a crimp.

[0193] For example, a polyimide layer is disposed on at least a portion of a stainless steel portion forming a crimp 2413. A conductive layer, such as copper, is then disposed on the polyimide layer, which is electrically coupled to one or more signal traces 2415 disposed on a buckle actuator. Deforming the crimp to contact the SMA lines therein also makes the SMA lines electrically contact the conductive layer. Thus, the conductive layer with the one or more signal traces is used to apply electrical signals to the SMA lines using techniques including those described herein. For some embodiments, a second polyimide layer is formed in areas of the conductive layer above the conductive layer where it will not contact the SMA lines. For some embodiments, a lamination forming crimp connector 2412 is formed on the crimp 2413 using deposition and etching techniques including those known in this art. In other embodiments, the laminated crimp connector 2412 and one or more electrical traces are formed independently of the crimp 2413 and the buckle actuator and are attached to the crimp 2413 and the buckle actuator using techniques including welding, adhesives and other techniques known in this art.

[0194] Figure 29 illustrates an SMA actuator including a buckle actuator with a laminated hammock. As shown in Figure 29, when an electrical signal is applied, the SMA line contracts or shortens to move the buckle arm and the laminated hammock in the positive z-axis direction. The laminated hammock, in contact with an object, then moves that object, such as a lens holder, in the positive z-axis direction. When the electrical signal decreases or is removed, the SMA line extends and moves the buckle arm and the laminated hammock in a negative z-axis direction.

[0195] Figure 30 illustrates an exploded view of an SMA system including an SMA actuator according to one embodiment, the SMA actuator comprising a buckle actuator. As described herein, for some embodiments, the SMA system is configured to be used together with one or more camera lens elements as an autofocus actuator. As illustrated in Figure 30, the SMA system includes a return spring 3003, configured, according to various embodiments, to move a lens holder 3006 in the opposite direction of the z-stroke direction when the tension in the SMA line 3008 decreases as the actuation of the SMA line is deactivated. For some embodiments, the SMA system includes a reinforcement 3000 disposed on the return spring 3003. For some embodiments, the SMA system includes a housing 3009 formed of two parts configured to receive the return spring 3003 and act on a sliding bearing to guide the lens holder in the z-stroke direction. The housing 3009 is also configured to be disposed on the buckle actuator 3002. The buckle actuator 3002 includes a slide base 3001 similar to one of the slide bases described herein, the slide base 3001 being formed of two parts. The slide base 3001 is split to electrically isolate the two sides (e.g., one side is grounded and the other side is powered), because according to some embodiments, current flows through a portion of the slide base 3001 to the line.

[0196] The buckle actuator 3002 includes a buckle arm 3004. Each pair of buckle actuators 3002 is formed on a separate portion of the buckle actuator 3002. The buckle actuator 3002 also includes an SMA wire attachment structure, such as a resistance-bonded wire crimp 3012. The SMA system may include, where appropriate, a flexible circuit 3020 for electrically coupling the SMA wire 3008 to one or more control circuits.

[0197] As shown in Figure 30, a sliding base 3001 is mounted on an optional adapter plate 3014. This adapter plate is configured to allow the SMA system or buckle actuator 3002 to engage with another system (such as an OIS, an additional SMA system, or other components). Figure 31 illustrates an SMA system 3101 according to one embodiment, which includes an SMA actuator comprising a buckle actuator 3002.

[0198] Figure 32 illustrates an SMA actuator including a buckle actuator according to one embodiment. The buckle actuator 3002 includes a buckle arm 3004. The buckle arm 3004 is configured to move on the z-axis when the SMA line 3008 is actuated and de-actuated as described herein. The SMA line 3008 is attached to a resistance-bonded wire crimp 3012. According to the embodiment illustrated in Figure 32, the buckle arm 3004 is configured to mate with an object such as a lens holder without using a central portion of a double-yoke capture connector.

[0199] Figure 33 illustrates a double-yoke capture joint of one of the buckle arms of an SMA actuator according to one embodiment. Figure 33 also illustrates an electroplated pad for attaching optional flexible circuitry to a sliding base. For some embodiments, the electroplated pad 3022 is made of gold. Figure 34 illustrates a resistance-welded press-fit of an SMA actuator according to one embodiment, which is used to attach an SMA wire to a buckle actuator. For some embodiments, adhesive or bonding agent may also be applied to the top of the weld to enhance mechanical strength and provide fatigue strain relief during operation and impact loading.

[0200] Figure 35 illustrates an SMA actuator including a buckle actuator with a double-yoke capture joint. As shown in Figure 35, when an electrical signal is applied, the SMA line contracts or shortens to move the buckle arm in the positive z-direction. The double-yoke capture joint contacts an object, which then moves in the positive z-direction, such as a lens holder. When the electrical signal decreases or is eliminated, the SMA line extends and moves the buckle arm in a negative z-axis direction. This yoke capture feature ensures that the buckle arm remains in the correct position relative to the lens holder.

[0201] Figure 36 illustrates an SMA dual piezoelectric crystal liquid lens according to one embodiment. The SMA dual piezoelectric crystal liquid lens 3501 includes a liquid lens sub-assembly 3502, a housing 3504, and circuitry with an SMA actuator 3506. For various embodiments, the SMA actuator includes four dual piezoelectric crystal actuators 3508, such as those described herein. The dual piezoelectric crystal actuators 3508 are configured to actuate a shaped ring 3510 positioned on a flexible diaphragm 3512. This ring wraps around the diaphragm 3512 / liquid 3514, thereby altering the light path through the diaphragm 3512 / liquid 3514. An integral receiving ring 3516 is used to receive the liquid 3514 between the diaphragm 3512 and the lens 3518. Equal forces from the dual piezoelectric crystal actuators alter the focal point of the image in the Z direction (normal to the lens), allowing it to be used as an autofocus device. According to some embodiments, the differential force from the dual piezoelectric chip actuator 3508 can move light in the X and Y axis directions, allowing it to be used as an optical image stabilizer. By properly controlling each actuator, both OIS and AF functions can be achieved simultaneously. For some embodiments, three actuators are used. The circuit 3506 with SMA actuators includes contacts 3520 for actuating one or more SMA actuators with control signals. According to some embodiments including four SMA actuators, the circuit 3506 with SMA actuators includes four power circuit control contacts for each SMA actuator and a common reset contact.

[0202] Figure 37 illustrates a perspective view of an SMA dual piezoelectric crystal liquid lens according to one embodiment. Figure 38 illustrates a cross-section and a bottom view of an SMA dual piezoelectric crystal liquid lens according to one embodiment.

[0203] Figure 39 illustrates an SMA system according to one embodiment, including an SMA actuator 3902 with dual piezoelectric crystal actuators. The SMA actuator 3902 includes four dual piezoelectric crystal actuators using the technology described herein. Two of these dual piezoelectric crystal actuators are configured as positive z-stroke actuators 3904, and the other two are configured as negative z-stroke actuators 3906, as illustrated in Figure 40, which illustrates an SMA actuator 3902 with dual piezoelectric crystal actuators according to one embodiment. The actuators 3906 and 3904 are configured to control movement in two directions over the entire stroke. This provides tuning control codes to compensate for tilt. For each embodiment, two SMA lines 3908 attached to the top of the component achieve positive z-stroke displacement. Two SMA lines attached to the bottom of a component achieve negative z-stroke displacement. In some embodiments, tabs are used to attach dual piezoelectric wafer actuators to an object, such as a lens holder 3910, for engagement. The SMA system includes a top spring 3912 configured to provide stability of the lens holder 3910 on an axis perpendicular to the z-stroke axis (e.g., in the x and y directions). Furthermore, a top spacer 3914 is configured to be disposed between the top spring 3912 and the SMA actuator 3902. A bottom spacer 3916 is disposed between the SMA actuator 3902 and a bottom spring 3918. The bottom spring 3918 is configured to provide stability of the lens holder 3910 on an axis perpendicular to the z-stroke axis (e.g., in the x and y directions). The bottom spring 3918 is configured to be mounted on a base 3920, such as those described herein.

[0204] Figure 41 illustrates the length 4102 of a dual piezoelectric chip actuator 4103 and the position for an SMA wire 4106 extending beyond one of the bonding pads 4104 of the dual piezoelectric chip actuator. The wire extending beyond the dual piezoelectric chip actuator increases the stroke and force. Therefore, the extension length 4108 of the SMA wire 4106 beyond the dual piezoelectric chip actuator 4103 is used to set the stroke and force of the dual piezoelectric chip actuator 4103.

[0205] Figure 42 illustrates an exploded view of an SMA system including a dual piezoelectric chip actuator 4202 according to one embodiment. According to various embodiments, the SMA system is configured to use separate metallic materials and non-conductive adhesives to create one or more circuits to independently power the SMA lines. Some embodiments do not have AF size influence and include four dual piezoelectric chip actuators, such as those described herein. Two of these dual piezoelectric chip actuators are configured as positive z-stroke actuators and the other two are configured as negative z-stroke actuators. Figure 43 illustrates an exploded view of a sub-section of an SMA actuator according to one embodiment. This sub-section includes a negative actuator signal connector 4302 and a base 4304 having a dual piezoelectric chip actuator 4306. The negative actuator signal connector 4302 includes a wire bonding pad 4308 for connecting one SMA line of the dual piezoelectric chip actuator 4306 using techniques including those described herein. A negative actuator signal connector 4302 is attached to the base 4304 using an adhesive layer 4310. This sub-section also includes a positive actuator signal connector 4314 with a wire bonding pad 4316 for connecting an SMA wire 4312b of a dual piezoelectric crystal actuator 4306 using techniques including those described herein. A positive actuator signal connector 4314 is attached to the base 4304 using an adhesive layer 4318. The base 4304, the negative actuator signal connector 4302, and the positive actuator signal connector 4314 are all made of metal, such as stainless steel. Connecting pads 4322 on each of the base 4304, negative actuator signal connector 4302, and positive actuator signal connector 4314 are configured to electrically couple control signals and ground to actuate the dual piezoelectric chip actuator 4306 using techniques incorporating those described herein. In some embodiments, connecting pads 4322 are gold-plated. Figure 44 illustrates a sub-section of an SMA actuator according to one embodiment. In some embodiments, gold-plated pads are formed on a stainless steel layer for solder bonding or other known electrical termination methods. Additionally, shaped wire bonding pads are used for signal connectors to electrically couple SMA lines for power signals.

[0206] Figure 45 illustrates a 5-axis sensor shifting system according to one embodiment. The 5-axis sensor shifting system is configured to move an object, such as an image sensor, relative to one or more lenses along five axes. This includes X / Y / Z-axis translation and tilt / roll. Alternatively, the system may be configured to use only four axes, with X / Y-axis translation and tilt / roll performed together with a single AF on top for Z-motion. Other embodiments include a 5-axis sensor shifting system configured to move one or more lenses relative to an image sensor. For some embodiments, a static lens stack is mounted on a top cover and inserted inside the ID (without contacting the internal orange moving bracket).

[0207] Figure 46 illustrates an exploded view of a 5-axis sensor shifting system according to one embodiment. The 5-axis sensor shifting system includes two circuit components: a flexible sensor circuit 4602, a dual piezoelectric chip actuator circuit 4604, and eight to twelve dual piezoelectric chip actuators 4606 mounted on the dual piezoelectric chip circuit components using techniques including those described herein. The 5-axis sensor shifting system includes a movable carriage 4608 configured to hold one or more lenses and a housing 4610. According to one embodiment, the dual piezoelectric chip actuator circuit 4604 includes eight to twelve SMA actuators, such as those described herein. The SMA actuators are configured to move the movable carriage 4608 along five axes similar to other 5-axis systems described herein, such as in the x-direction, y-direction, z-direction, pitch, and roll.

[0208] Figure 47 illustrates an SMA actuator, according to one embodiment, comprising dual piezoelectric chip actuators integrated into this circuit to perform all motions. An embodiment of an SMA actuator may include 8 to 12 dual piezoelectric chip actuators 4606. However, other embodiments may include more or fewer dual piezoelectric chip actuators 4606. Figure 48 illustrates an SMA actuator 4802, according to one embodiment, comprising dual piezoelectric chip actuators integrated into this circuit to perform all motions, the SMA actuator 4802 being partially configured to be housed within a corresponding housing 4804. Figure 49 illustrates a cross-section of a 5-axis sensor shifting system according to one embodiment.

[0209] Figure 50 illustrates an SMA actuator 5002 comprising a dual piezoelectric chip actuator according to one embodiment. The SMA actuator 5002 is configured to move an image sensor, lens, or other various payload in the x and y directions using a four-sided mounted SMA dual piezoelectric chip actuator 5004. Figure 51 illustrates a top view of an SMA actuator comprising a dual piezoelectric chip actuator that moves an image sensor, lens, or other various payload in different x and y positions.

[0210] Figure 52 illustrates an SMA actuator according to an embodiment, comprising a dual piezoelectric crystal actuator 5202 configured as a box-type dual piezoelectric crystal autofocus device. Four top- and bottom-mounted SMA dual piezoelectric crystal actuators (such as those described herein) are configured to move together to generate movement in the z-stroke direction for autofocusing motion. Figure 53 illustrates an SMA actuator according to an embodiment, comprising dual piezoelectric crystal actuators, with two top-mounted dual piezoelectric crystal actuators 5302 configured to push one or more lenses. Figure 54 illustrates an SMA actuator according to an embodiment, comprising dual piezoelectric crystal actuators, with two bottom-mounted dual piezoelectric crystal actuators 5402 configured to push one or more lenses. Figure 55 illustrates an SMA actuator including a dual piezoelectric chip actuator according to one embodiment, showing four top- and bottom-mounted SMA dual piezoelectric chip actuators 5502 (such as the SMA dual piezoelectric chip actuators described herein) for moving one or more lenses to produce tilting motion.

[0211] Figure 56 illustrates an SMA system according to one embodiment, including an SMA actuator comprising a dual piezoelectric crystal actuator configured as a biaxial lens shifting OIS. For some embodiments, the biaxial lens shifting OIS is configured to move a lens along the X / Y axes. For some embodiments, Z-axis movement originates from a single AF, such as the AF described herein. Four dual piezoelectric crystal actuators actuate the sides of the autofocus device to perform OIS movement. Figure 57 illustrates an exploded view of an SMA system according to one embodiment, including an SMA actuator 5802 comprising a dual piezoelectric crystal actuator 5806 configured as a biaxial lens shifting OIS. Figure 58 illustrates a cross-section of an SMA system according to one embodiment, including an SMA actuator 5802 comprising a dual piezoelectric crystal actuator 5806 configured as a biaxial lens shifting OIS. Figure 59 illustrates a cartridge-type dual piezoelectric crystal actuator 5802 for use in an SMA system according to one embodiment. The cartridge-type dual piezoelectric crystal actuator 5802 is configured as a biaxial lens shifting OIS manufactured prior to its forming for use in the system. This system can be configured to have a high OIS stroke OIS (e.g., + / - 200 μm or higher). Furthermore, these embodiments are configured to use four sliding bearings, such as POM sliding bearings, to achieve a wide range of motion and good OIS dynamic tilt. These embodiments are configured for easy integration with AF designs (e.g., VCM or SMA).

[0212] Figure 60 illustrates an SMA system according to one embodiment, including an SMA actuator comprising a dual piezoelectric crystal actuator configured as a 5-axis lens shift OIS and autofocus device. In some embodiments, the 5-axis lens shift OIS and autofocus device are configured to move a lens along the X / Y / Z axes. In some embodiments, tilt and yaw axis movements are used for dynamic tilt tuning capability. Using the techniques described herein, eight dual piezoelectric crystal actuators are used to provide movement for the autofocus device and OIS. Figure 61 illustrates an exploded view of an SMA system according to one embodiment, including an SMA actuator 6202 comprising a dual piezoelectric crystal actuator 6204 configured as a 5-axis lens shift OIS and autofocus device according to one embodiment. Figure 62 illustrates a cross-section of an SMA system including an SMA actuator 6202 according to one embodiment. The SMA actuator 6202 includes a dual piezoelectric wafer actuator 6204 configured as a 5-axis lens shift OIS and autofocus device. Figure 63 illustrates a cartridge-type dual piezoelectric wafer actuator 6202 for an SMA system according to one embodiment. The cartridge-type dual piezoelectric wafer actuator 6202 is configured as a 5-axis lens shift OIS and autofocus device manufactured before being formed and equipped in the system. This system can be configured to have a high OIS stroke (e.g., + / - 200 μm or higher) and a high autofocus stroke (e.g., 400 μm or higher). Furthermore, these embodiments can detune any tilt and eliminate the need for a separate autofocus assembly.

[0213] Figure 64 illustrates an SMA system according to one embodiment, comprising an SMA actuator including a dual piezoelectric crystal actuator configured as an external pushbox. In some embodiments, the dual piezoelectric crystal actuator assembly is configured to wrap around an object such as a lens holder. Since the circuit assembly moves with the lens holder, a flexible portion is configured for low X / Y / Z stiffness. The tail pad of the circuit is static. The external pushbox can be configured for both four and eight dual piezoelectric crystal actuators. Thus, the external pushbox can be configured as a set of four dual piezoelectric crystal actuators located on the OIS side and movable along the X and Y axes. The external pushbox can also be configured as a set of four dual piezoelectric crystal actuators on the top and bottom for automatic focusing during movement along the Z-axis. The push-out box can be configured to be located on the top, bottom, and sides of the OIS and autofocus device, and to move along the x, y, and z axes, and to be capable of 3-axis tilting (tilt / roll / pick). Figure 65 illustrates an exploded view of an SMA system according to one embodiment, including an SMA actuator 6602, which includes a dual piezoelectric crystal actuator 6604 configured as a push-out box. Thus, the SMA actuator is configured such that the dual piezoelectric crystal actuator acts on a housing 6504 to move a lens holder 6506 using the techniques described herein. Figure 66 illustrates an SMA system according to one embodiment, including an SMA actuator 6602, which includes a dual piezoelectric crystal actuator configured to partially form a push-out box receiving a lens holder 6603. Figure 67 illustrates an SMA system according to one embodiment, including an SMA actuator 6602, the SMA actuator 6602 including a dual piezoelectric chip actuator 6604 configured to be manufactured in an ejector box before being formed and equipped in the system.

[0214] Figure 68 illustrates an SMA system according to one embodiment, including an SMA actuator 6802, which comprises a dual piezoelectric chip actuator 6806 configured as a 3-axis sensor-shifted OIS. For some embodiments, z-axis movement originates from a separate autofocus system. Four dual piezoelectric chip actuators are configured to push the sides of a sensor carrier 6804 using the techniques described herein to provide motion relative to the OIS. Figure 69 illustrates an exploded view of an SMA according to one embodiment, including an SMA actuator 6802, which comprises a dual piezoelectric chip actuator 6806 configured as a 3-axis sensor-shifted OIS. Figure 70 illustrates a cross-section of an SMA system according to one embodiment, including an SMA actuator 6802, which comprises a dual piezoelectric chip actuator 6806 configured as a 3-axis sensor-shifted OIS. Figure 71 illustrates a cartridge-type dual piezoelectric chip actuator 6802 assembly for use in an SMA system according to one embodiment, the cartridge-type dual piezoelectric chip actuator 6802 assembly being configured as a 3-axis sensor shifting OIS manufactured before being formed and equipped in the system. Figure 72 illustrates a flexible sensor circuit for use in an SMA system according to one embodiment, the flexible sensor circuit being configured as a 3-axis sensor shifting OIS. This system can be configured to have a high OIS stroke OIS (e.g., + / - 200 μm or higher) and a high autofocus stroke (e.g., 400 μm or higher). Furthermore, these embodiments are configured to use four sliding bearings, such as POM sliding bearings, to achieve a wide biaxial range of motion and good OIS dynamic tilt. These embodiments are configured for easy integration with AF designs (e.g., VCM or SMA).

[0215] Figure 73 illustrates an SMA system according to one embodiment, including an SMA actuator comprising a dual piezoelectric crystal actuator 7404 configured as a 6-axis sensor-shifting OIS and autofocus device. In some embodiments, the 6-axis sensor-shifting OIS and autofocus device are configured to move a lens on X / Y / Z / tilt / roll axes. In some embodiments, the tilt and roll axis movements are used for dynamic tilt tuning capability. Using the techniques described herein, eight dual piezoelectric crystal actuators are used to provide motion for the autofocus device and OIS. Figure 74 illustrates an exploded view of an SMA system according to one embodiment, including an SMA actuator 7402 comprising a dual piezoelectric crystal actuator 7404 configured as a 6-axis sensor-shifting OIS and autofocus device. Figure 75 illustrates a cross-section of an SMA system including an SMA actuator 7402 according to one embodiment. The SMA actuator 7402 includes a dual piezoelectric wafer actuator configured as a 6-axis sensor shift OIS and autofocus device. Figure 76 illustrates a cartridge dual piezoelectric wafer actuator 7402 for an SMA system according to one embodiment. The cartridge dual piezoelectric wafer actuator 7402 is configured as a 6-axis sensor shift OIS and autofocus device manufactured before being formed and equipped in the system. Figure 77 illustrates a flexible sensor circuit for an SMA system according to one embodiment, configured as a 3-axis sensor shift OIS. This system can be configured to have a high OIS stroke (e.g., + / - 200 μm or higher) and a high autofocus stroke (e.g., 400 μm or higher). Furthermore, these embodiments can detune any tilt and eliminate the need for a separate autofocus assembly.

[0216] Figure 78 illustrates an SMA system according to one embodiment, including an SMA actuator comprising a dual piezoelectric crystal actuator configured as a dual-axis camera tilt OIS. For some embodiments, the dual-axis camera tilt OIS is configured to move a camera on a tilt / roll axis. Using the techniques described herein, four dual piezoelectric crystal actuators are used to actuate the top and bottom of an autofocus device to achieve the entire camera movement of the OIS tilt and roll motion. Figure 79 illustrates an exploded view of an SMA system according to one embodiment, including an SMA actuator 7902 comprising a dual piezoelectric crystal actuator 7904 configured as a dual-axis camera tilt OIS. Figure 80 illustrates a cross-section of an SMA system according to one embodiment, including an SMA actuator comprising a dual piezoelectric crystal actuator configured as a dual-axis camera tilt OIS. Figure 81 illustrates a cartridge-type dual piezoelectric chip actuator for an SMA system according to one embodiment, the cartridge-type dual piezoelectric chip actuator being configured as a dual-axis camera tilt OIS manufactured prior to being formed and equipped in the system. Figure 82 illustrates a flexible sensor circuit for an SMA system according to one embodiment, the flexible sensor circuit being configured as a dual-axis camera tilt OIS. This system can be configured to have a high OIS stroke OIS (e.g., ±3 degrees or higher). These embodiments are configured for easy integration with autofocus ("AF") designs (e.g., VCM or SMA).

[0217] Figure 83 illustrates an SMA system according to one embodiment, including an SMA actuator comprising a dual piezoelectric crystal actuator configured as a 3-axis camera tilt OIS. For some embodiments, the 3-axis camera tilt OIS is configured to move a camera on a tilt / roll / tilt axis. Using the techniques described herein, four dual piezoelectric crystal actuators are used to actuate the top and bottom of the autofocus unit to achieve the entire camera movement of the OIS tilt and roll motion, and using the techniques described herein, four dual piezoelectric crystal actuators are used to actuate the sides of the autofocus unit to achieve the entire camera movement of the OIS roll motion. Figure 84 illustrates an exploded view of an SMA system according to one embodiment, including an SMA actuator 8402 comprising a dual piezoelectric crystal actuator 8404 configured as a 3-axis camera tilt OIS. Figure 85 illustrates a cross-section of an SMA system including an SMA actuator according to one embodiment, the SMA actuator comprising a dual piezoelectric crystal actuator configured as a 3-axis camera tilt OIS. Figure 86 illustrates a cartridge dual piezoelectric crystal actuator for an SMA system according to one embodiment, the cartridge dual piezoelectric crystal actuator being configured as a 3-axis camera tilt OIS manufactured prior to its forming as an assembly in the system. Figure 87 illustrates a flexible sensor circuit for an SMA system according to one embodiment, the flexible sensor circuit being configured as a 3-axis camera tilt OIS. This system can be configured to have a high OIS stroke OIS (e.g., ±3 degrees or higher). These embodiments are configured for easy integration with AF designs (e.g., VCM or SMA).

[0218] Figure 88 illustrates exemplary dimensions of a dual piezoelectric chip actuator according to one embodiment of an SMA actuator. These dimensions are preferred embodiments, but those skilled in the art will understand that other dimensions can be used based on the desired characteristics of an SMA actuator.

[0219] Figure 89 illustrates a lens system for a folding camera according to one embodiment. The folding camera includes a folding lens 8902 configured to bend light into a lens system 8901 comprising one or more lenses 8903a to 8903d. For some embodiments, the folding lens is any one or more of a prism and lenses. The lens system 8901 is configured to have a principal axis 8904 angled relative to a transmission axis 8906 parallel to the direction of light travel before reaching the folding lens 8902. For example, a folding camera is used in a camera phone system to reduce the height of the lens system 8901 in the direction of the transmission axis 8906.

[0220] Embodiments of the lens system include one or more liquid lenses, such as those described herein. The embodiment illustrated in Figure 89 includes two liquid lenses 8903b and 8903d, such as those described herein. One or more liquid lenses 8903b and 8903d are configured to be actuated using techniques including those described herein. An actuator is used to actuate a liquid lens, including, but not limited to, buckle actuators, dual piezoelectric chip actuators, and other SMA actuators. Figure 108 illustrates a liquid lens actuated using a buckle actuator 60 according to one embodiment. The liquid lens includes a shaped ring coupler 64, a liquid lens assembly 61, one or more buckle actuators 60 (such as buckle actuators described herein), a sliding base 65, and a base 62. One or more buckle actuators 60 are configured to move the shaping ring / coupler 64 to change the shape of a flexible diaphragm in the liquid lens assembly 61 to move or shape light, as described herein, for example. For some embodiments, three or four actuators are used. A liquid lens can be configured alone or in combination with other lens configurations to act as an autofocus device or optical image stabilizer. A liquid lens can also be configured to otherwise guide an image onto an image sensor.

[0221] Figure 90 illustrates several embodiments of a lens system 9001, which includes liquid lenses 9002a to 9002h to focus an image onto an image sensor 9004. As illustrated, the liquid lenses 9002a to 9002h may include any lens shape and be configured to dynamically adjust the light path through the lenses using techniques including those described herein.

[0222] A lens system for a folding camera is configured to include an actuated folding lens 9100. One example of an actuated folding lens is a tilting prism, such as the tilting prism illustrated in FIG. 91. In the example illustrated in FIG. 91, the folding lens is a prism 9102 mounted on an actuator 9104. This actuator includes, but is not limited to, an SMA actuator, including the SMA actuators described herein. For some embodiments, the tilting prism is mounted on an SMA actuator comprising four dual piezoelectric crystal actuators 9106, such as the dual piezoelectric crystal actuators described herein. According to some embodiments, using techniques including those described herein, the actuated folding lens 9100 is configured as an optical image stabilizer. For example, the actuated folding lens is configured to include an SMA system, such as the SMA system illustrated in FIG. 39. Another example of a unidirectional folding lens may include an SMA actuator, such as the SMA actuator illustrated in Figure 21. However, the folding lens may also include other actuators.

[0223] Figure 92 illustrates a dual piezoelectric wafer arm with an offset according to one embodiment. The dual piezoelectric wafer arm 9201 includes a dual piezoelectric wafer beam 9202 having a length 9208 and a shaping offset 9203. Compared to a dual piezoelectric wafer arm without an offset, the shaping offset 9203 provides a mechanical advantage to generate a higher force. According to some embodiments, the depth of the offset 9204 (also referred to herein as the bending plane z-offset 9204) and the length of the offset 9206 (also referred to herein as the slot width 9206) are configured to define the characteristics of the dual piezoelectric wafer arm, such as peak force. For example, the graph in Figure 106 illustrates the relationship between the bending plane z-offset 9204, the slot width 9206, and the peak force of a dual piezoelectric wafer beam 9202 according to one embodiment.

[0224] The dual piezoelectric wafer arm comprises one or more SMA materials, such as an SMA strip or SMA wire 9210, as described herein. The SMA material is attached to the beam using techniques including those described herein. For some embodiments, an SMA material, such as an SMA wire 9210, is attached to a fixed end 9212 and a load point end 9214 of the dual piezoelectric wafer arm, such that a forming offset 9203 is positioned between the two ends of the attached SMA material. For various embodiments, the ends of the SMA material are electrically and mechanically coupled to contacts configured to supply current to the SMA material using techniques known in this art. A dual piezoelectric wafer arm with an offset can be included in SMA actuators and systems such as those described herein.

[0225] Figure 93 illustrates a dual piezoelectric wafer arm with an offset and a limiter according to one embodiment. The dual piezoelectric wafer arm 9301 includes a dual piezoelectric wafer beam 9302 having a forming offset 9303 and a limiter 9304 adjacent to the forming offset 9303. Compared to a dual piezoelectric wafer arm 9301 without an offset, the offset 9303 provides a mechanical advantage to generate a higher force, and the limiter 9304 prevents the arm from moving in a direction away from the unfixed, load-point end 9306 of the dual piezoelectric wafer actuator. The dual piezoelectric wafer arm 9301 with a forming offset 9303 and a limiter 9304 can be included in SMA actuators and systems such as those described herein. The dual piezoelectric wafer arm 9301 includes one or more SMA materials such as an SMA strip or SMA wire 9308, such as the SMA material described herein attached to the dual piezoelectric wafer arm 9301 using techniques incorporating the techniques described herein.

[0226] Figure 94 illustrates a dual piezoelectric wafer arm with an offset and a limiter according to one embodiment. The dual piezoelectric wafer arm 9401 includes a dual piezoelectric wafer beam 9402 having a forming offset 9403 and a limiter 9404 adjacent to the forming offset 9403. The limiter 9404 is formed as part of a base 9406 for the dual piezoelectric wafer arm 9401. The base 9406 is configured to receive a dual piezoelectric wafer arm 9401 and includes a recess 9408 configured to receive the offset portion of the dual piezoelectric wafer beam. The bottom of the recess is configured to be adjacent to the limiter 9404 of the forming offset 9403. The base 9406 may also include one or more portions 9410 configured to support the dual piezoelectric wafer arm when it is not actuated. A dual piezoelectric wafer arm 9401 having a forming offset 9403 and a limiter 9404 may be included in an SMA actuator and system such as those described herein. The dual piezoelectric wafer arm 9401 includes one or more SMA materials such as an SMA strip or SMA wire, such as the SMA material described herein attached to the dual piezoelectric wafer arm 9401 using techniques incorporating the techniques described herein.

[0227] Figure 95 illustrates one embodiment of a base including a dual piezoelectric wafer arm with an offset, according to one embodiment. The dual piezoelectric wafer arm 9501 includes a dual piezoelectric wafer beam 9502 with a shaped offset 9504. The dual piezoelectric wafer arm may also use a limiter incorporating the techniques described herein. The dual piezoelectric wafer arm 9501 includes one or more SMA materials such as an SMA strip or SMA wire 9506, such as the SMA material described herein attached to the dual piezoelectric wafer arm 9501 using techniques incorporating the techniques described herein.

[0228] Figure 96 illustrates one embodiment of a base 9608 comprising two bipiezoelectric wafer arms having an offset. Each bipiezoelectric wafer arm 9601a, 9601b comprises a bipiezoelectric wafer beam 9602a, 9602b having a forming offset 9604a, 9604b. Each bipiezoelectric wafer arm 9601a, 9601b comprises one or more SMA materials such as an SMA tape or SMA line 9606a, 9606b, such as the SMA material described herein attached to the bipiezoelectric wafer arm 9601 using a technique incorporating the technology described herein. Each bipiezoelectric wafer arm 9601a, 9601b may also use a limiter incorporating the technology described herein. Some embodiments include a base comprising two or more bipiezoelectric wafer arms formed using a technique incorporating the technology described herein. According to some embodiments, the bipiezoelectric wafer arms 9601 are integrally formed with the base 9608. In other embodiments, using techniques including, but not limited to, solder, resistance welding, laser welding, and adhesives, one or more of the dual piezoelectric chip arms 9601a, 9601b are formed independently of and attached to the base 9608. In some embodiments, two or more dual piezoelectric chip arms 9601a, 9601b are configured to act on a single object. This implementation has the capability to increase the force applied to an object. The graph in Figure 107 below illustrates an example of how the box volume, as an approximation of a box surrounding the entire dual piezoelectric chip actuator, relates to the power of each dual piezoelectric chip assembly. The box volume (collectively referred to as the "box volume") is approximated using the length of one of the dual piezoelectric chip actuators 9612, the width of one of the dual piezoelectric chip actuators 9610, and the height of one of the dual piezoelectric chip actuators 9614.

[0229] Figure 97 illustrates a buckle arm including load point extensions according to one embodiment. The buckle arm 9701 includes a beam portion 9702 and one or more load point extensions 9704a, 9704b extending from the beam portion 9702. Each end 9706a, 9706b of the buckle arm 9701 is configured to be attached to or integrally formed to or onto a plate or other base using techniques including those described herein. According to some embodiments, one or more load point extensions 9704a, 9704b are attached to or integrally formed with the beam portion 9702 at an offset from one of the load points 9710a, 9710b of the beam portion 9702. The load points 9710a, 9710b are portions of the beam portion 9702, configured to transmit forces from the buckle arm 9701 to another object. For some embodiments, the load points 9710a, 9710b are at the center of the beam portion 9702. In other embodiments, load points 9710a and 9710b are located at a position other than the center of beam portion 9702. Load point extensions 9704a and 9704b are configured to extend along the longitudinal axis of beam portion 9702 from the point connecting to beam portion 9702 toward load points 9710a and 9710b of beam portion 9702. In some embodiments, the ends of load point extensions 9704a and 9704b extend to at least load points 9710a and 9704b of beam portion 9702. The buckle arm 9701 comprises one or more SMA materials, such as an SMA strip or SMA line 9712, as described herein. An SMA material, such as an SMA line 9712, is attached to opposite ends of beam portion 9702. The SMA material is attached to opposite ends of beam portion using techniques incorporating those described herein. For some embodiments, the lengths of the load point extensions 9704a and 9704b can be configured to be any length contained within the longitudinal length of the associated flat (removed actuation) beam portion 9702 of the buckle arm 9701.

[0230] Figure 98 illustrates a buckle arm 9801 according to an embodiment, including a load point extension 9810 in a uniformly actuated position. SMA material attached to the opposite end of a beam portion 9802 is actuated using techniques incorporating those described herein. The load point 9804 allows the buckle arm 9801 to increase the stroke range on the buckle arm without the extension. Therefore, a buckle arm including a load point extension can achieve a greater maximum vertical stroke. A buckle arm with a load point extension can be included in SMA actuators and systems such as those described herein.

[0231] Figure 99 illustrates a dual piezoelectric wafer arm including load point extensions according to one embodiment. The dual piezoelectric wafer arm 9901 includes a beam portion 9902 and one or more load point extensions 9904a, 9904b extending from the beam portion. One end of the dual piezoelectric wafer arm 9901 is configured to be attached or integrally formed to a plate or other base using techniques including those described herein. The end of the beam portion 9902 opposite to the attached or integrally formed end is not fixed and is freely movable. According to some embodiments, one or more load point extensions 9904a, 9904b are attached or integrally formed to the beam portion 9902 with an offset from one of the free ends of the beam portion 9902. The load point extensions 9904a, 9904b are configured to extend from a point connected to the beam portion 9902 in a direction remote from the longitudinal axis of the beam portion 9902. For example, the load point extensions 9904a and 9904b extend in the direction of extension when the free end of the beam portion is actuated. Some embodiments of a dual piezoelectric wafer arm 9901 include one or more load point extensions 9904a and 9904b having a longitudinal axis that forms an angle of 1 to 90 degrees with a plane including the longitudinal axis of the beam portion. In some embodiments, the ends 9910a and 9910b of the load point extensions 9904a and 9904b are configured to engage an object configured to be moved.

[0232] The dual piezoelectric chip arm 9901 includes one or more SMA materials, such as an SMA strip or SMA line 9906, as described herein. An SMA material, such as an SMA line 9906, is attached to opposite ends of the beam portion 9902. The SMA material is attached to opposite ends of the beam portion 9902 using techniques incorporating those described herein. For some embodiments, the lengths of the load point extensions 9904a, 9904b can be configured to any length. According to some embodiments, the location of the point where an object is engaged by one end 9910a, 9910b of the load point extensions 9904a, 9904b can be configured to any point along the longitudinal length of the beam portion 9902. When the beam portion at one end of a load point extension is flat (actuated), the height above that beam portion can be configured to any height. In some embodiments, when the dual piezoelectric wafer arm is actuated, the load point extension may be configured to be at least above other portions of the dual piezoelectric wafer arm.

[0233] Figure 100 illustrates a dual piezoelectric wafer arm according to an embodiment, including a load point extension in a unidirectional moving position. SMA material attached to opposite ends of beam portion 2 is actuated using a technique incorporating the technology described herein. Compared to a dual piezoelectric wafer arm without an extension, the load point extension 10 allows the dual piezoelectric wafer arm 1 to increase the stroke force. Therefore, the dual piezoelectric wafer arm 1 including the load point extension 10 achieves the application of a greater force by the dual piezoelectric wafer arm 1. The dual piezoelectric wafer arm 1 with the load point extension 10 can be included in SMA actuators and systems such as those described herein.

[0234] Figure 101 illustrates an SMA optical image stabilizer according to one embodiment. The SMA optical image stabilizer 20 includes a movable plate 22 and a static plate 24. The movable plate 22 includes a spring arm 26 integrally formed therefrom. In some embodiments, the movable plate 22 and the static plate 24 are each formed as a single, one-piece plate. The movable plate 22 includes a first SMA material attachment portion 28a and a second SMA material attachment portion 28b. The static plate 24 includes a first SMA material attachment portion 30a and a second SMA material attachment portion 30b. Each SMA material attachment portion 28, 30 is configured to use a resistance welding head to fix an SMA material, such as an SMA wire, to a plate. The first SMA material attachment portion 28a of the movable plate 22 includes a first SMA line 32a disposed between it and a first SMA material attachment portion 30a of the static plate, and a second SMA line 32b disposed between it and a second SMA attachment portion 30b of the static plate 24. The second SMA material attachment portion 28b of the movable plate 22 includes a third SMA line 32c disposed between it and a second SMA material attachment portion 30b of the static plate, and a fourth SMA line 32d disposed between it and the first SMA attachment portion 30a of the static plate 24. The SMA lines are actuated using techniques including those described herein to move the movable plate 22 away from the static plate 24. Figure 102 illustrates an SMA material attachment portion 40 of a movable portion according to one embodiment. The SMA material attachment portion is configured to have SMA material, such as an SMA line 41, resistively bonded to the SMA material attachment portion 40. Figure 103 illustrates, according to one embodiment, a resistance-welded SMA wire 43 attached to an SMA attachment portion 42 of a static plate.

[0235] Figure 104 illustrates an SMA actuator 45 including a buckle actuator according to one embodiment. The buckle actuator 46 includes a buckle arm 47, such as the buckle arm described herein. The buckle arm 47 is configured to move along the z-axis when actuating and de-actuating the SMA line 48 using a technique including the techniques described herein. Each SMA line 48 is attached to a respective resistance-bonded wire crimp portion 49 using resistance welding. Each resistance-bonded wire crimp 49 includes an island 50 isolated from metal, the island 50 forming the buckle arm 47 on at least one side of the SMA line 48. This island structure can be used in other actuators, optical image stabilizers, and autofocus systems to connect at least one side of an SMA line to an isolated island structure formed in an alkali metal layer, such as the OIS application shown in Figure 101.

[0236] Figure 105 illustrates a resistance-welded press-fit comprising an island for an SMA actuator according to one embodiment, the SMA actuator being used to attach an SMA wire 48 to a buckle actuator 46 using techniques including those described herein. Figure 105a illustrates a bottom portion of an SMA actuator 45. According to some embodiments, the SMA actuator 45 is formed from a stainless steel substrate 51. A dielectric layer 52, such as a polyimide layer, is disposed on the bottom portion of the stainless steel substrate 51. According to some embodiments, a conductor layer 53 is electrically connected to the stainless steel island 50 through a via in the dielectric layer 52, thereby enabling an electrical connection between the wire welded to the stainless steel island 50 and the conductor circuit attached to the stainless steel island. According to some embodiments, an island 50 is etched from the stainless steel substrate 50. The dielectric layer 52 maintains the position of the island 50 within the stainless steel substrate 51. The island 50 is configured to attach an SMA wire to it using techniques including those described herein (e.g., resistance welding). Figure 105b illustrates the top portion of one of the SMA actuators 45 including an island 50. In some embodiments, glue or adhesive may also be placed on the top of the weld to aid mechanical strength and to relieve fatigue strain during operation and impact loads.

[0237] Figure 108 illustrates a lens system with an SMA actuator having a buckle actuator according to one embodiment. The lens system includes a liquid lens assembly 61 mounted on a base 62. The lens system also includes a forming ring / coupler 64 mechanically coupled to the buckle actuator 60. The SMA actuator 60, including a buckle actuator such as those described herein, is mounted on a sliding base 65, which is mounted on the base 62. The SMA actuator is configured to move the forming ring / coupler 64 along the optical axis of the liquid lens assembly 61 by actuating the buckle actuator 60 using techniques including those described herein. This movement of the forming ring / coupler 64 changes the focal point of the liquid lens in the liquid lens assembly.

[0238] Figure 109 illustrates an unfixed, load point end of one of the dual piezoelectric wafer arms according to one embodiment. The unfixed, load point end 70 of a dual piezoelectric wafer arm includes a flat surface 71 for attaching an SMA material, such as an SMA wire 72. The SMA wire 72 is attached to the flat surface 71 by a resistance solder 73. The resistance solder 73 is formed using techniques including those known in this art.

[0239] Figure 110 illustrates an unfixed, load point end of one of the dual piezoelectric wafer arms according to one embodiment. The unfixed, load point end 76 of a dual piezoelectric wafer arm includes a flat surface 77 for attaching an SMA material, such as an SMA wire 78. The SMA wire 78 is attached to the flat surface 77 by a resistance weld similar to that illustrated in Figure 109. An adhesive 79 is disposed on the resistance weld. This achieves a more reliable connection between the SMA wire 78 and the unfixed, load point end 76. The adhesive 79 includes, but is not limited to, conductive adhesives, non-conductive adhesives, and other adhesives known in this art.

[0240] Figure 111 illustrates an unfixed, load point 80 of a dual piezoelectric wafer arm according to one embodiment. The unfixed, load point 80 of a dual piezoelectric wafer arm includes a flat surface 81 for attaching an SMA material, such as an SMA wire 82. A metal interlayer 84 is disposed on the flat surface 81. The metal interlayer 84 includes, but is not limited to, a gold layer, a nickel layer, or an alloy layer. The SMA wire 82 is attached to the metal interlayer 84 disposed on the flat surface 81 by a resistance weld 83. The resistance weld 83 is formed using techniques including those known in this art. The metal interlayer 84 achieves better adhesion to the unfixed, load point 80.

[0241] Figure 112 illustrates an unfixed, load-bearing end 88 of a dual piezoelectric wafer arm according to one embodiment. The unfixed, load-bearing end 88 of a dual piezoelectric wafer arm includes a flat surface 89 for attaching an SMA material, such as an SMA wire 90. A metal interlayer 92 is disposed on the flat surface 89. The metal interlayer 92 includes, but is not limited to, a gold layer, a nickel layer, or an alloy layer. The SMA wire 90 is attached to the flat surface 89 by a resistance weld similar to that illustrated in Figure 111. An adhesive 91 is disposed on the resistance weld. This achieves a more reliable connection between the SMA wire 90 and the unfixed, load-bearing end 88. The adhesive 91 includes, but is not limited to, conductive adhesives, non-conductive adhesives, and other adhesives known in this art.

[0242] Figure 113 illustrates a fixed end of a dual piezoelectric wafer arm according to one embodiment. The fixed end 95 of a dual piezoelectric wafer arm includes a flat surface 96 for attaching an SMA material, such as an SMA wire 97. The SMA wire 97 is attached to the flat surface 96 by a resistance solder 98. The resistance solder 98 is formed using techniques including those known in this art.

[0243] Figure 114 illustrates a fixed end of a dual piezoelectric wafer arm according to one embodiment. The fixed end 120 of a dual piezoelectric wafer arm includes a flat surface 121 for attaching an SMA material, such as an SMA wire 122. The SMA wire 122 is attached to the flat surface 121 by a resistance weld similar to that illustrated in Figure 113. An adhesive 123 is disposed on the resistance weld. This achieves a more reliable connection between the SMA wire 122 and the fixed end 120. The adhesive 123 includes, but is not limited to, conductive adhesives, non-conductive adhesives, and other adhesives known in the art.

[0244] Figure 115 illustrates a fixed end of a dual piezoelectric wafer arm according to one embodiment. The fixed end 126 of a dual piezoelectric wafer arm includes a flat surface 127 for attaching an SMA material, such as an SMA wire 128. A metal interlayer 130 is disposed on the flat surface 127. The metal interlayer 130 includes, but is not limited to, a gold layer, a nickel layer, or an alloy layer. The SMA wire 128 is attached to the metal interlayer 130 disposed on the flat surface 127 by a resistance weld 129. The resistance weld 129 is formed using techniques including those known in this art. The metal interlayer 130 achieves better adhesion to the fixed end 126.

[0245] Figure 116 illustrates a fixed end of a dual piezoelectric wafer arm according to one embodiment. The fixed end 135 of the dual piezoelectric wafer arm includes a flat surface 136 for attaching an SMA material, such as an SMA wire 137. A metal interlayer 138 is disposed on the flat surface 136. The metal interlayer 138 includes, but is not limited to, a gold layer, a nickel layer, or an alloy layer. The SMA wire 137 is attached to the flat surface 136 by a resistance weld similar to that illustrated in Figure 115. An adhesive 139 is disposed on the resistance weld. This achieves a more reliable connection between the SMA wire 137 and the fixed end 135. The adhesive 139 includes, but is not limited to, conductive adhesives, non-conductive adhesives, and other adhesives known in the art.

[0246] Figure 117 illustrates a rear view of one of the fixed ends of a dual piezoelectric wafer arm according to one embodiment. The dual piezoelectric wafer arm is configured according to the embodiments described herein. The fixed end 143 of a dual piezoelectric wafer arm includes an island 144 isolated from an exterior 145 of the fixed end 143. This allows the island 144 to be electrically and / or thermally isolated from the exterior 145. For some embodiments, SMA material attached to the opposite side of the fixed end 143 of the dual piezoelectric wafer arm is electrically coupled to SMA material such as an SMA wire through a through-hole. The island 144 is disposed on an insulator 146, such as the insulator described herein. The island 144 can be formed using an etching technique including etching techniques known in the art.

[0247] Figure 118 illustrates an unfixed, load point 870 of a dual piezoelectric wafer arm according to one embodiment. The unfixed, load point 870 of a dual piezoelectric wafer arm includes a flat surface 871 configured to include a radiating surface region 874 extending from a resistance soldering region 873. The radiating surface region 874 includes a distal portion 876 and a proximal portion 875. The flat surface 871 is configured to have an SMA material, such as an SMA wire 872, attached to the flat surface 871. According to some embodiments, the SMA wire 872 is attached to the flat surface 871 at a resistance soldering region 873 by resistance soldering. The resistance soldering is performed using techniques known in this art. For other embodiments, the SMA wire 872 is attached to the flat surface 871 using other attachment techniques including those described herein.

[0248] The temperature decrease at the unfixed, load point 870 is related to the phase transition temperature of the SMA line 872. The radiating surface region 874 significantly increases the surface area of ​​the unfixed load point 870.

[0249] The increased surface area improves the unfixed temperature at the 870°C load point. The increased surface area enables cooling to prevent shape memory alloy phase transformation during actuation.

[0250] Figure 119 illustrates an unfixed, load point 170 of one of the dual piezoelectric wafer arms according to one embodiment. The unfixed, load point 170 of the dual piezoelectric wafer arm includes a flat surface 171 configured to include a radiating surface region 174 extending from the resistance solder area 173.

[0251] The radiating surface region 174 includes a distal portion 176 and a proximal portion 175. The flat surface 171 is configured to have an SMA material, such as an SMA line 172, attached to the flat surface 171. According to some embodiments, the SMA line 172 is attached to the flat surface 171 by resistance welding to a resistance welding zone 173. For other embodiments, the SMA line 172 is attached to the flat surface 171 using other attachment techniques including the attachment techniques described herein.

[0252] The unfixed, load point end 170 also includes a near-end aperture 178 and a far-end aperture 179 separated by resistance soldering area 173. The near-end aperture 178 and the far-end aperture 179 are formed using techniques known in this art. Although apertures 178 and 179 are depicted as full-through features, in some instances apertures 178 and 179 may be partially etched.

[0253] A near-end aperture 178 and a far-end aperture 179 physically disrupt the flat surface 171 and define the location of the resistance soldering zone 173. According to some embodiments, apertures 178 and 179 are configured to reduce interference between line 172 and the flat surface 171 adjacent to the resistance soldering zone 173.

[0254] Figure 120 illustrates an unfixed, load point 270 of a dual piezoelectric chip arm according to one embodiment. The unfixed, load point 270 of a dual piezoelectric chip arm includes a flat surface 271 configured to include a radiating surface region 274 extending from a resistance soldering region 273. The flat surface 271 is configured to have an SMA material, such as an SMA line 272, attached to the flat surface 271. According to some embodiments, the SMA line 272 is attached to the flat surface 271 by resistance soldering to a resistance soldering region 273. For other embodiments, the SMA line 272 is attached to the flat surface 271 using other attachment techniques including the attachment techniques described herein.

[0255] The unfixed, load point end 270 also includes a proximal aperture 278 and a distal aperture 279 separated by resistance soldering area 273. The unfixed, load point end 270 also includes an elongated aperture 280 corresponding to a segment of SMA line 272. The elongated aperture 280 can be removed to create a gap in the SMA line 272. In some embodiments, the elongated aperture 280 extends from the proximal aperture 278. Although apertures 278, 279, and 280 are depicted as full-through features, in some instances apertures 278, 279, and 280 may be partially etched.

[0256] A near-end aperture 278 and a far-end aperture 279 substantially disrupt the flat surface 271 and define the location of the resistance soldering zone 273. Similarly, an elongated aperture 280 substantially disrupts the flat surface 271 and defines the location of the SMA line 272. According to some embodiments, apertures 278, 279, and 280 are configured to mitigate interference between the line 272 and the flat surface 271 adjacent to the resistance soldering zone 273.

[0257] Figure 121 illustrates an unfixed, load point end 370 of one of the dual piezoelectric wafer arms according to one embodiment. A flat surface 371 is configured to have an SMA material, such as an SMA line 372, attached to the flat surface 371. According to some embodiments, the SMA line 372 is attached to the flat surface 371 by resistance soldering to a resistance solder area 373, which is at least partially isolated by a nonlinear aperture 378. In some configurations, the nonlinear aperture 378 is U-shaped, substantially isolating up to 90% of the resistance solder area 373. The resistance solder area 373 may be mounted on a solder tongue defined by the nonlinear aperture 378. For other embodiments, the SMA line 372 is attached to the flat surface 371 using other attachment techniques including those described herein. Although the nonlinear aperture 378 is illustrated as an all-through feature, in some instances the nonlinear aperture 378 may be partially etched.

[0258] The increased surface area from the radiating surface region 374 enables cooling to prevent shape memory alloy phase transformation during actuation. In some alternative embodiments, the resistance solder area 373 may be completely etched from the unfixed, load point end 370. Alternatively, the resistance solder area 373 may also contain a portion of etched slots to increase the compliance of the tongue.

[0259] Figure 122 illustrates an unfixed, load point end 470 of one of the dual piezoelectric chip arms according to one embodiment. An adjacent flat surface 471 is provided for mounting an SMA material, such as an SMA line 472. The SMA line 472 is attached to the flat surface 471 via a resistance soldering region 473, which is at least partially isolated by a non-linear aperture 478.

[0260] The resistance soldering zone 473 can be mounted using a portion of the nonlinear aperture 478 etched slot 479. In some configurations, the nonlinear aperture 478 physically disrupts the flat surface 471 and defines the location of the resistance soldering zone 473. According to some embodiments, the aperture 478 is configured to mitigate interference between the line 472 and the flat surface 471 adjacent to the resistance soldering zone 473. Although the aperture 478 is depicted as a full-through feature, in some instances the aperture 478 may be partially etched.

[0261] The increased surface area from the radiating surface region 474 enables cooling to prevent shape memory alloy phase transformation during actuation.

[0262] The disclosed embodiments can be applied to the fixed end of a dual piezoelectric wafer arm. Figures 123 to 125 are provided herein as example embodiments of the fixed end incorporated into the disclosed embodiments.

[0263] Figure 123 illustrates a fixed end of a dual piezoelectric wafer arm according to one embodiment. The fixed end 895 of a dual piezoelectric wafer arm includes a flat surface 896 for attaching an SMA material, such as an SMA wire 897. The SMA wire 897 is attached to the flat surface 896 via a resistance solder joint 898. The resistance solder joint 898 is formed using techniques including those known in this art.

[0264] The fixed end 895 includes a proximal aperture 893 and a distal aperture 894 separated by a resistance welding zone 898. The proximal aperture 893 and the distal aperture 894 are formed using techniques known in this art.

[0265] A near-end aperture 893 and a far-end aperture 894 physically disrupt the flat surface 896 and define the location of the resistance weld 898. According to some embodiments, apertures 893 and 894 are configured to mitigate interference between the SMA line 897 and the flat surface 896 adjacent to the resistance weld area 898. Although apertures 893 and 894 are depicted as full-through features, in some instances, apertures 893 and 894 may be partially etched.

[0266] Figure 124 illustrates a fixed end of a dual piezoelectric wafer arm according to one embodiment. The fixed end 195 of the dual piezoelectric wafer arm includes a flat surface 196 for attaching an SMA material, such as an SMA wire 197. The SMA wire 197 is attached to the flat surface 196 by resistance soldering at a resistance soldering zone 198. The resistance soldering zone 198 is formed using techniques including those known in this art.

[0267] The fixed end 195 includes a proximal aperture 193 and a distal aperture 194 separated by a resistance welding zone 198. The proximal aperture 193 and the distal aperture 194 are formed using techniques known in this art.

[0268] The fixed end 195 also includes an elongated aperture 160 corresponding to a segment of the SMA line 197. The elongated aperture 160 can be removed to provide a line gap for the SMA line 197. In some embodiments, the elongated aperture 160 extends from the distal aperture 194.

[0269] A near-end aperture 193 and a far-end aperture 194 at least partially and physically isolate the resistance soldering area 198. An elongated aperture 160 physically disrupts the flat surface 196 and defines the location of the SMA line 197. According to some embodiments, apertures 193 and 194 are configured to mitigate interference between the SMA line 197 and the flat surface 196 adjacent to the resistance soldering area 198. Although apertures 193 and 194 are depicted as full-through features, in some instances, apertures 193 and 194 may be partially etched.

[0270] Figure 125 illustrates a fixed end 295 of a dual piezoelectric chip arm according to one embodiment. The fixed end 295 of a dual piezoelectric chip arm includes a flat surface 296 for attaching SMA material, such as an SMA wire 297. The SMA wire 297 is attached to the flat surface 296 by resistance soldering at a resistance soldering zone 298.

[0271] The resistance soldering area 298 is at least partially isolated by a nonlinear aperture 294. In some configurations, the nonlinear aperture 294 is U-shaped to physically isolate up to 90% of the resistance soldering area 298. The resistance soldering area 298 can be mounted on a solder tongue defined by the nonlinear aperture 294.

[0272] The nonlinear aperture 294 physically disrupts the flat surface 296 and defines the location of the resistance solder area 298. According to some embodiments, the linear aperture 294 is configured to mitigate interference between the SMA line 297 and the flat surface 296 adjacent to the resistance solder area 298. In some alternative embodiments, the resistance solder area 298 may be completely etched from the fixed end 295. Alternatively, the resistance solder area 298 may also contain a portion of etched slots to reduce a contact area.

[0273] Figure 126 illustrates a balanced dual piezoelectric chip actuator according to one embodiment. The balanced dual piezoelectric chip actuator 440 includes two dual piezoelectric chip arms 442, 443 formed and configured using techniques including those described herein. For some embodiments, the dual piezoelectric chip actuator 440 is fixed to a base 441, such as a bracket for mounting to a housing. The dual piezoelectric chip actuator 440 is fixed to the base using techniques (such as adhesives and solders) including those known in this art. The balanced dual piezoelectric chip actuator 440 is configured to reduce the net friction of the dual piezoelectric chip actuator 440 by minimizing or eliminating its own frictional components 444a, 444b, because it includes two dual piezoelectric chip arms 442, 443 arranged in opposite directions. The frictional force components 444a and 444b of each bipiezoelectric crystal arm 442, 443 act in a direction different from the desired force strokes 445a and 445b of each bipiezoelectric crystal arm 442, 443. According to some embodiments, a balanced bipiezoelectric crystal actuator 440 includes at least one first bipiezoelectric crystal arm 442 and at least one other bipiezoelectric crystal arm 443 configured to have frictional force components 444a and 444b acting in a direction opposite to that of the first bipiezoelectric crystal arm 442. Therefore, the balanced bipiezoelectric crystal actuator 440 is configured to balance the sliding friction caused by the frictional force components of one or more bipiezoelectric crystal arms. This allows for more precise control with less or no need for actively counteracting unwanted frictional forces. Balanced bipiezoelectric crystal actuators, including those described herein, overcome the problem of other bipiezoelectric crystal actuators generating a frictional force component at the tip. These other dual piezoelectric chip actuators generate thrust in the Y direction and, due to sliding along the surface of the actuator's actuating member in the X direction, produce an unwanted force in the X direction. This will generate a small amount of unwanted motion in the X direction that the control system must compensate for. However, these compensated dual piezoelectric chip actuators will also generate their own unwanted frictional forces. This requires complex control algorithms to achieve good motion performance, for example, in an optical image stabilization system.

[0274] Figure 127 illustrates an optical image stabilization system comprising balanced dual piezoelectric chip actuators according to one embodiment. All side-mounted balanced dual piezoelectric chip actuators 448a to 448d are used to eliminate their own frictional components, as they are configured in opposite directions using techniques incorporating those described herein. In the case of near-zero net friction, a minimum open-loop position error exists. In some instances, this small error will be attributable to typical assembly and component size tolerances and can be easily corrected by using a closed-loop control system.

[0275] Figure 128 illustrates a balanced dual piezoelectric chip actuator according to one embodiment. The balanced dual piezoelectric chip actuator 450 includes two dual piezoelectric chip arms 452a, 452b arranged in a linear, mirror-oriented configuration, such as those described herein. In some embodiments, the dual piezoelectric chip actuator 450 is fixed to a base 453, such as a bracket for mounting to a housing. The dual piezoelectric chip actuator 450 is fixed to the base using techniques including those known in the art (such as adhesives and solders). According to some embodiments, a first dual piezoelectric chip arm 452a is configured to have a frictional component 454a primarily in the direction parallel to the longitudinal axis of one of the balanced dual piezoelectric chip actuators at its fixed end 456a. The second dual piezoelectric chip arm 452b is configured to be in parallel with the first dual piezoelectric chip arm 452a such that the fixed end 456b of the second dual piezoelectric chip arm is adjacent to the fixed end of the first dual piezoelectric chip arm 456a. The second dual piezoelectric chip arm 452b is configured to have a frictional component 454b in a direction opposite to that of the first dual piezoelectric chip arm 452a. This results in the dual piezoelectric chip actuator being configured to reduce the net frictional force of the dual piezoelectric chip actuator by minimizing or eliminating the net frictional force. For some embodiments, for a balanced dual piezoelectric chip actuator, the net frictional force is approximately zero net total frictional force. For some embodiments, each dual piezoelectric chip arm 452a, 452b of the balanced dual piezoelectric chip actuator includes an SMA line 458a, 458b. The SMA lines 458a, 458b are connected in series and configured to receive equal current to both lines. In some embodiments, the first SMA line 458a is coupled to an actuator control element, for example, through a channel input for controlling the actuation of the actuator and through a first dual piezoelectric chip arm 452a coupled to a control input pad 451a. The second SMA line 458b is coupled to ground through a second dual piezoelectric chip arm 452b coupled to a ground pad 451b.

[0276] Figure 129 illustrates a balanced dual piezoelectric chip actuator according to one embodiment, comprising a polyimide layer 459 configured to hold and isolate metal components. Other embodiments of the balanced dual piezoelectric chip actuator do not include a polyimide layer. For some embodiments of the balanced dual piezoelectric chip actuator without a polyimide layer, a control input pad, a ground pad, and a common base island are fixed to a base layer between the fixed ends of a first dual piezoelectric chip arm and a second dual piezoelectric chip arm. For some embodiments, the control input pad, ground pad, and common base island are fixed to a base layer using an adhesive (such as adhesives known in the art). Figure 130 illustrates a balanced dual piezoelectric chip actuator according to one embodiment, comprising a common base island 460. The common base island 460 is configured for attaching one end of a first SMA line and one end of a second SMA line. In some embodiments, the common base island 460 is electrically isolated from a control input pad 461a and a ground pad 461b before any SMA line is attached to it. The common base island 460 is formed on the fixed ends of the first dual piezoelectric chip arm 462a and the second dual piezoelectric chip arm 462b.

[0277] Figure 131 illustrates a balanced dual piezoelectric wafer actuator according to one embodiment. The balanced dual piezoelectric wafer actuator includes two dual piezoelectric wafer arms 464a, 464b arranged in an anti-in-line orientation, such as those described herein. For some embodiments, the dual piezoelectric wafer actuator is fixed to a base 463, such as a bracket for mounting to a housing. The dual piezoelectric wafer actuator is fixed to the base using techniques known in the art (such as adhesives and solders). According to some embodiments, a first dual piezoelectric wafer arm 464a is configured to have a frictional component 466a primarily in the direction parallel to a longitudinal axis of the balanced dual piezoelectric wafer actuator at its fixed end 468a. The second dual piezoelectric chip arm 464b is configured to be in parallel with the first dual piezoelectric chip arm 464a, such that the fixed ends 468a and 468b of the dual piezoelectric chip arms 464a and 464b are attached to opposite ends of the dual piezoelectric chip actuator. Therefore, the unfixed ends 469a and 469b of the first and second dual piezoelectric chip arms are positioned close to each other. The second dual piezoelectric chip arm 464b is configured to have a frictional component 466b in the opposite direction to the first dual piezoelectric chip arm 464a. This results in the dual piezoelectric chip actuator being configured to reduce net friction by minimizing or eliminating net friction. For some embodiments, for a balanced dual piezoelectric chip actuator, the net friction is approximately zero net total friction. In some embodiments, each of the dual piezoelectric chip arms 464a, 464b of the balanced dual piezoelectric chip actuator includes an SMA line 467a, 467b. The SMA lines 467a, 467b are connected in series and configured to receive equal current to both lines, for example, through a channel input used to control the actuator's actuation. In some embodiments, the first SMA line 467a is coupled to an actuation control element, for example, through a channel input used to control the actuator's actuation, via a first dual piezoelectric chip arm 452a coupled to a control input pad 451a. The second SMA line 458b is coupled to ground through a second dual piezoelectric chip arm 452b coupled to a ground pad 451b.

[0278] Figure 132 illustrates a balanced dual piezoelectric chip actuator according to one embodiment, using the technology described herein, comprising a polyimide layer 570 configured to hold and isolate metal components. Other embodiments of the balanced dual piezoelectric chip actuator do not include a polyimide layer. For some embodiments of the balanced dual piezoelectric chip actuator without a polyimide layer, a control input pad and a ground pad are fixed near the first and second dual piezoelectric chip arms. For some embodiments, the control input pad and a ground pad are fixed to a substrate using an adhesive (such as adhesives known in this art). Figure 133 illustrates a balanced dual piezoelectric chip actuator according to one embodiment, using the technology described herein, comprising a control input pad 572 and a ground pad 573.

[0279] Figure 134 illustrates a balanced dual piezoelectric chip actuator according to one embodiment. The balanced dual piezoelectric chip actuator includes two dual piezoelectric chip arms 574a and 574b arranged in a linear, mirror-oriented configuration, such as those described herein. For some embodiments, the dual piezoelectric chip actuator is fixed to a base 571, such as a bracket for mounting to a housing. The dual piezoelectric chip actuator is fixed to the base using techniques known in the art, such as adhesives and solders. According to some embodiments, a first dual piezoelectric chip arm 574a is configured to have a frictional component 575a primarily in the direction parallel to the longitudinal axis of one of the balanced dual piezoelectric chip actuators at its fixed end 576a. The second dual piezoelectric chip arm 574b is configured in parallel with the first dual piezoelectric chip arm 574a such that the fixed end 576b of the second dual piezoelectric chip arm is adjacent to the fixed end 576a of the first dual piezoelectric chip arm. The second dual piezoelectric chip arm 574b is configured to have a frictional component 575b in a direction opposite to the frictional component 575a of the first dual piezoelectric chip arm. This results in the dual piezoelectric chip actuator being configured to reduce the net frictional force of the dual piezoelectric chip actuator by minimizing or eliminating the net frictional force. For some embodiments, for a balanced dual piezoelectric chip actuator, the net frictional force is approximately zero net total frictional force. For some embodiments, a single SMA line 578 is used, and each end of the SMA line 578 is coupled to an unfixed end of one of the dual piezoelectric chip arms 577a, 577b. The single SMA line 578 can achieve a greater stroke in the balanced dual piezoelectric chip actuator.

[0280] Figure 135 illustrates a balanced dual piezoelectric chip actuator comprising a single SMA line 579 according to an embodiment using the technology described herein. Figure 136 illustrates a balanced dual piezoelectric chip actuator according to an embodiment using the technology described herein, configured for a single SMA line and comprising a control input pad 480 and a ground pad 481. For some embodiments, the balanced dual piezoelectric chip actuator is configured to include a polyimide layer configured to hold and isolate metal components. Other embodiments of the balanced dual piezoelectric chip actuator do not include a polyimide layer. For some embodiments of the balanced dual piezoelectric chip actuator without a polyimide layer, a control input pad and a ground pad are fixed to a base layer between the fixed ends of a first dual piezoelectric chip arm and a second dual piezoelectric chip arm. For some embodiments, the control input pad and a ground pad are fixed to a base layer using an adhesive (such as adhesives known in this art).

[0281] Figure 137 illustrates a balanced dual piezoelectric wafer actuator according to one embodiment. The balanced dual piezoelectric wafer actuator includes two dual piezoelectric wafer arms 482a, 482b arranged in an interleaved orientation, such as those described herein. For some embodiments, the dual piezoelectric wafer actuator is fixed to a base 489, such as a bracket for mounting to a housing. The dual piezoelectric wafer actuator is fixed to the base using techniques known in the art, such as adhesives and solders. According to some embodiments, a first dual piezoelectric wafer arm 482a is configured to have a frictional component 483a primarily in the direction parallel to one of the longitudinal axes of the first dual piezoelectric wafer arm 482a at its fixed end 484a. A second dual piezoelectric wafer arm 482b is configured to interleave with the first dual piezoelectric wafer arm 482a such that the longitudinal axis of the second dual piezoelectric wafer arm is substantially parallel to the longitudinal axis of the first dual piezoelectric wafer arm. Furthermore, the fixed ends 484a and 484b of the dual piezoelectric chip arms 482a and 482b are located at opposite ends of the dual piezoelectric chip actuator. Therefore, the unfixed ends of the first dual piezoelectric chip arm 482a and the second dual piezoelectric chip 482b are interleaved relative to each other. The second dual piezoelectric chip arm 482a is configured to have a frictional force component 483a in a direction opposite to that of the first dual piezoelectric chip arm 482a. This results in the dual piezoelectric chip actuator being configured to reduce the net frictional force by minimizing or eliminating the net frictional force. For some embodiments, for a balanced dual piezoelectric chip actuator, the net frictional force is approximately zero net total frictional force. For some embodiments, each dual piezoelectric chip arm 482a and 482b of the balanced dual piezoelectric chip actuator includes an SMA line 485a and 485b. SMA lines 485a and 485b are connected in series and configured to receive equal current to both lines, for example, through one of the channel inputs used to control the actuation of an actuator (such as the actuator described herein).

[0282] Figure 138 illustrates a balanced dual piezoelectric chip actuator with an interleaved orientation according to one embodiment, the balanced dual piezoelectric chip actuator including a polyimide layer 486 configured to hold and isolate metal components. Other embodiments of the balanced dual piezoelectric chip actuator do not include a polyimide layer. For some embodiments of the balanced dual piezoelectric chip actuator without a polyimide layer, a control input pad and a ground pad are fixed adjacent to a first dual piezoelectric chip arm and a second dual piezoelectric chip arm. For some embodiments, the control input pad and a ground pad are fixed to the substrate using an adhesive (such as an adhesive described herein). Figure 139 illustrates a balanced dual piezoelectric chip actuator according to one embodiment including a control input pad 487 and a ground pad 488.

[0283] Figure 140 illustrates an optical image stabilization system comprising balanced dual piezoelectric crystal actuators according to one embodiment. Since the balanced dual piezoelectric crystal actuators on all sides are configured in opposite directions, these actuators are used to eliminate their own frictional components. Under near-zero friction conditions, a minimum open-loop position error exists. In some instances, this small error will be attributed to typical assembly and component size tolerances and can be easily corrected using a closed-loop control system.

[0284] Figure 141 illustrates an exploded view of an optical image stabilization system including a balanced dual piezoelectric chip actuator according to one embodiment. The optical image stabilization system is configured to receive dual piezoelectric chip actuators, such as those described herein, flush-positioned within recesses 510a to 510d surrounding a housing 511. This configuration achieves a smaller X / Y coverage area for dual piezoelectric chip modules 512a to 512d by allowing the dual piezoelectric chip actuators 514a to 514d (such as the balanced dual piezoelectric chip actuators described herein) to share the same X / Y space within the housing 511. This also simplifies the assembly of dual piezoelectric chip modules 512a to 512d by allowing the dual piezoelectric chip actuators 510a to 510d to be inserted externally in a final step. The housing 511 may be made of molded plastic, metal, or other materials.

[0285] Figure 142 illustrates an optical image stabilization system including balanced dual piezoelectric chip actuators according to one embodiment. An optical image stabilization housing 516 is configured to receive dual piezoelectric chip actuators 518a to 518d, such as those described herein, flush-positioned within a recess in the housing 516. This configuration achieves a smaller X / Y coverage area for dual piezoelectric chip modules 520a to 520d by allowing the dual piezoelectric chip actuators 518a to 518d (such as the balanced dual piezoelectric chip actuators described herein) to share the same X / Y space within the housing. This also simplifies the assembly of dual piezoelectric chip modules 520a to 520d by allowing the dual piezoelectric chip actuators 518a to 518d to be inserted externally in a final step. The housing 516 may be made of molded plastic, metal, or other materials.

[0286] Figure 143 illustrates a sensor-shift optical image stabilization system including dual piezoelectric chip actuators according to one embodiment. The optical image stabilization system is configured to receive balanced dual piezoelectric chip actuators configured as a balanced bracket / module 522a to 522d, such as those described herein. The dual piezoelectric chip brackets / modules 522a to 522d are configured for external insertion from the sensor-shift OIS module. In some embodiments, the sensor-shift OIS module uses an eccentric design of the dual piezoelectric chip actuators to also induce rotation of the image sensor 524 mounted on a moving image sensor bracket 528 that can be controlled to suppress roll excitation and X / Y excitation. This configuration achieves a smaller X / Y coverage area for one of the dual piezoelectric chip modules 522a-522d by allowing dual piezoelectric chip actuators (such as the balanced dual piezoelectric chip actuators described herein) to share the same X / Y space within the housing 526. The assembly of the dual piezoelectric chip modules 522a-d is also simplified by allowing the dual piezoelectric chip actuators to be inserted externally in the final stage. The housing 526 may be made of molded plastic, metal, or other materials.

[0287] Figure 144 illustrates an optical image stabilization system including a balanced dual piezoelectric chip actuator according to one embodiment. The optical image stabilization system is configured to receive a dual piezoelectric chip actuator, such as those described herein, flush-positioned within a recess 530 on an outer housing 532 of the optical image stabilization system. This configuration achieves a smaller X / Y coverage area for dual piezoelectric chip modules 534a to 534d by allowing the dual piezoelectric chip actuators (such as the balanced dual piezoelectric chip actuators described herein) to share the same X / Y space within the housing 532. This also simplifies the assembly of the dual piezoelectric chip modules 534a to 534d by allowing the dual piezoelectric chip actuators to be inserted externally in a final step. The housing 532 may be made of molded plastic, metal, or other materials.

[0288] Figure 145 illustrates a metal housing 536 for an optical image stabilization system according to an embodiment described herein, the optical image stabilization system being manufactured as a molded metal attached to molding plastics 538a to 538d in an insert molding process. Figure 146 illustrates an embodiment of the metal housing / shell 536 including recesses 542a to 542d formed on four sides of the metal housing / shell 536 configured to allow flush mounting of dual piezoelectric chip actuators 544a to 544d (such as dual piezoelectric chip actuators described herein).

[0289] Figure 147 illustrates an exploded view of an optical image stabilization (OIS) system comprising a balanced dual piezoelectric chip actuator and a plurality of centering springs according to one embodiment. The OIS system includes an autofocus (AF) actuator 400 having four AF solder connectors 402 or other electrical connections that transmit current between the AF actuator 400 and a focus control circuit. For some embodiments, the autofocus actuator 400 includes one or more SMA actuators, such as those disclosed herein. According to some embodiments, the AF actuator 400 is mounted on a base 404 coupled to the AF actuator 400. According to some embodiments, the base 404 includes four isolation sections, each of which is attached to springs 406a to 406d. In some embodiments, the base 404 and springs 406a to 406d are each formed by a single flat assembly, which is divided into four isolated sections to generate four leaf spring circuits to control the movement of an object, such as the X / Y axis movement of an optical image stabilization system and / or the Z axis movement of an autofocus system.

[0290] In some embodiments, the isolation sections of the base 404 and / or springs 406a to 406d are formed using an etching process or other manufacturing techniques (such as those known in this art). To form four leaf spring circuits, springs 406a to 406d are soldered to the base 404 such that each of the four springs 406a to 406d is soldered to one of the four isolation sections of the base 404. In some embodiments, soldering is performed at solder points 408a to 408d included on each of the four leaf spring circuits, securing the springs 406a to 406d to the isolation sections of the base 404 to create four isolated electrical paths. In some embodiments, the four isolated electrical paths are configured for closed-loop AF. Four OIS solder connectors 410a to 410d are configured to connect the leaf spring circuits to the OIS control circuitry included in the dual piezoelectric chip OIS actuator 412. The OIS control circuit is configured to connect to a printed circuit board (PCB) to enable a camera control circuit to operate an AF actuator 400 and an OIS actuator 412, as disclosed herein.

[0291] Figure 148 illustrates a top view of an OIS system comprising one of four leaf spring circuits. According to some embodiments, leaf spring circuits 414a to 414d are configured as stainless steel (SST) circuits to provide a low-cost solution for controlling the movement of an image sensor. For some embodiments, leaf spring circuits 414a to 414d are formed of gold-plated 100-micron stainless steel. The rigidity of the springs comprising leaf spring circuits 414a to 414d provides a reliable and stable spring force for centering an AF actuator relative to an image sensor or otherwise controlling the movement of the AF actuator. Springs 416a to 416d included in leaf spring circuits 414a to 414d are configured to generate low stress during large changes in movement (e.g., movement in a positive or negative direction along an x-axis and / or a y-axis). For example, for some embodiments, the maximum stress on a spring during a 330-micron stroke is 425 MPa. Minimizing stress on the spring extends its service life (e.g., with fatigue below the infinite fatigue limit of <638 MPa), thereby improving the reliability of the OIS system compared to other motion control solutions. The spring is also configured to provide a downward force on a bearing (e.g., a bearing) of a support assembly to provide near-zero dynamic tilting effect on an AF module and / or an OIS system.

[0292] Figure 149 illustrates a base comprising one of four springs. According to one embodiment, springs 418a to 418d are freely formed to produce a preload (e.g., these springs may be freely formed such that the free end of the spring extends from the base by up to 6.4 mm in one positive or negative direction along the z-axis). For some embodiments, a spring is freely formed to have a preload in the range of 15 mN to 35 mN. The preload of one spring in an OIS system is configured to ensure that a moving mass (such as an AF actuator) is held against one or more bearings.

[0293] Freeforming springs 418a to 418d can reduce the deflection of springs 418a to 418d (e.g., the deflection of the spring is reduced to positive or negative 0.1 mm) to reduce the overall height requirement of the leaf spring circuit, such as the amount of space on the z-axis required for proper operation. Figure 150 illustrates spring 429 after it has been welded to the base to form the leaf spring circuit. One or more flat bends may be formed in the spring before it is freeformed. For some embodiments, a spring 429 includes a flat bend near each end of the spring 429. For example, a spring includes: a first flat bend 430 configured to have a bend in a negative direction, such as a negative 3.5 degrees on the z-axis; and / or a second flat bend 431 configured to have a bend in a positive direction, such as a positive 3.5 degrees on the z-axis. For some embodiments, the flat bend is in the range of 0 degrees to positive or negative 7 degrees. Other embodiments of the spring include a flattened bend configured to have a bending range within a desired range to meet design constraints. One or more of these flattened bends enable the spring to achieve a downward force (e.g., + / - 25 micronewtons (mN)) while minimizing spring deflection (e.g., arm deflection <0.1 mm under normal conditions and arm deflection <0.2 mm at full spring height). The flattened bends also configure the spring to move in one direction (e.g., a positive z-axis direction) to minimize the required clearance space below the leaf spring circuitry. Minimizing spring deflection and minimizing spring deflection in a positive z-axis direction reduces the amount of space occupied by the leaf spring circuitry (e.g., + / - 0.2 mm in the z-axis). Accordingly, flattening one or more of the bends in the leaf spring circuitry minimizes the impact of the OIS actuator on the overall camera height, thereby enabling the assembly of a smaller and more compact electronic camera system.

[0294] Figure 151 illustrates a dual piezoelectric chip actuator including a crimping element according to one embodiment. According to various embodiments, a dual piezoelectric chip actuator 1512 includes a beam 1514 (such as a beam described herein) and one or more SMA materials 1516 (such as an SMA tape or SMA wire 1516). For some embodiments, the SMA material (such as an SMA wire 1516) is attached to a fixed end 1518 (such as those described herein) and a load point end 1520 (such as a load point end described herein) of the dual piezoelectric chip actuator, such that the beam 1514 is positioned between the two ends to which the SMA material is attached. The fixed end 1518 includes a crimping portion 1522 configured to clamp downwards onto a portion of the SMA wire 1516 to attach the wire to a crimping portion 1522 of the fixed end 1518. The load point terminal 1520 includes a crimp portion 1524 configured to clamp downward onto a portion of the SMA wire 1516 for attaching the wire to a crimp portion 1520. In various embodiments, the SMA material end is electrically and mechanically coupled to contacts configured to supply current to the SMA material using techniques known in the art.

[0295] It will be understood that terms such as “top,” “bottom,” “above,” “below,” and the x, y, and z directions used herein as convenient terms indicate the spatial relationship of components relative to each other rather than any particular spatial or gravitational orientation. Therefore, these terms are intended to cover an assembly of component parts, regardless of whether the assembly is oriented in the particular orientation shown in the drawings and described in the specification, inverted from that orientation, or any other rotational variation.

[0296] It will be understood that the term "invention" as used herein should not be construed as representing only a single invention having a single basic element or group of elements. Similarly, it will be understood that the term "invention" encompasses several individual innovations, each of which can be considered an independent invention. Although the invention has been described in detail with respect to preferred embodiments and their drawings, it will be apparent to those skilled in the art that various adaptations and modifications of the embodiments of the invention can be made without departing from the spirit and scope of the invention. Furthermore, the techniques described herein can be used to manufacture devices having one of two, three, four, five, six, or more typically n dual piezoelectric chip actuators and buckle actuators. Accordingly, it should be understood that the detailed description set forth above and the accompanying drawings are not intended to limit the breadth of the invention, which should only be inferred from the following claims of the invention and their legitimate equivalents as suitably interpreted.

[0297] 1: Dual piezoelectric crystal arm 2: Beam section 10: Load Point Extension 20: Shape Memory Alloy (SMA) Optical Image Stabilizer 22: Mobile board 24: Static Panel 26: Spring Arm 28a: First SMA material attachment portion 28b: Second SMA material attachment portion 30a: First SMA material attachment portion 30b: Second SMA material attachment portion 32a-d: First SMA line 40: SMA material attachment part 41a: SMA line 41b: SMA line 43a: SMA line 43b: SMA line 42: SMA attachment part 46a: Buckle actuator 46b: Buckle actuator 47a-d: Buckle arm 48a: SMA line 48b: SMA line 49a: Resistance welding wire crimping material 49b: Resistance welding wire crimping material 45: SMA actuator 50: Island 51: Metal / Stainless Steel Base 52: Dielectric layer 53: Conductor layer 60: Buckle Actuator 61: Liquid Lens Assembly 62: Base 64: Formed ring coupler / Formed ring / Coupler 65: Sliding base 70: Unfixed, load point terminal 71: Flat surface 72: SMA line 73: Resistance Welding 76: Unfixed, load point terminal 77: Flat surface 78: SMA line 79: Adhesive 80: Unfixed, load point terminal 81: Flat surface 82: SMA line 83: Resistance Welding 84: Metal interlayer 88: Unfixed, load point terminal 89: Flat surface 90: SMA line 91: Adhesive 92: Metal sandwich 95: Fixed end 96: Flat surface 97: SMA line 98: Resistance Welding 100: Shape Memory Alloy (SMA) Wire 101: Base 102: Buckle Actuator 104: Central Part 106: Press-fit structure 108: z stroke direction 120: Fixed end 121: Flat surface 122: SMA line 123: Adhesive 126: Fixed end 127: Flat surface 128: SMA line 129: Resistance Welding 130: Metal interlayer 135: Fixed end 136: Flat surface 137: SMA line 138: Metal interlayer 139: Adhesive 143: Dual piezoelectric crystal arm / fixed end 144: Island 145: External 146: Insulator 160: Elongated aperture 170: Unfixed, load point terminal 171: Flat surface 172: SMA line 173: Resistance Welding Area 174: Radiation surface area 175: Proximal portion 176: Remote portion 178: Proximal aperture 179: Distal aperture 193: Proximal aperture 194: Distal aperture 195: Fixed end 196: Flat surface 197: SMA line 198: Resistance Welding Area 202: Dual Piezoelectric Chip Actuator 204: Base 206: SMA band 208: z stroke direction 270: Unfixed, load point terminal 271: Flat surface 272: SMA line 273: Resistance Welding Area 274: Radiation surface region 278: Proximal aperture 279: Distal aperture 280: Elongated aperture 294: Nonlinear aperture 295: Fixed end 296: Flat surface 297: SMA line 298: Resistance Welding Area 302: SMA actuator 304: Optical Image Stabilizer ("OIS") 306: Lens bracket 308: Return spring 310: Vertical sliding bearing 312: Guide Cover 370: Unfixed, load point terminal 371: Flat surface 372: SMA line 373: Resistance Welding Zone 374: Radiation surface area 378: Nonlinear aperture 400: Autofocus (AF) actuator 402:AF solder connector 404: Base 406a to 406d: Springs 408a to 408d: Solder joints 410a to 410d: OIS solder connectors 412: Dual piezoelectric chip OIS actuator 414a to 414d: Leaf Spring Circuit 416a to 416d: Springs 418a to 418d: Springs 429: Spring 430: First flat curved section 431: Second flat curved section 440: Balanced dual piezoelectric crystal actuator 441: Base 442: Dual piezoelectric wafer arm / First dual piezoelectric wafer arm 443: Dual piezoelectric wafer arm / Another dual piezoelectric wafer arm 444a: Friction component / Friction force component 444b: Friction component / Friction force component 445a: Force Stroke 445b: Force Stroke 448a to 448d: Balanced dual piezoelectric chip actuator 450: Balanced dual piezoelectric crystal actuator 451a: Control Input Pad 451b: Grounding mat 452a: Dual piezoelectric wafer arm / First dual piezoelectric wafer arm 452b: Dual piezoelectric wafer arm / Second dual piezoelectric wafer arm 453: Base 454a: Friction component 454b: Friction component 456a: First dual piezoelectric wafer arm 456b: Second dual piezoelectric wafer arm 458a: SMA line / First SMA line 458b: SMA line / Second SMA line 459: Polyimide layer 460: Common base island 461a: Control Input Pad 461b: Grounding mat 462a: First dual piezoelectric wafer arm 462b: Second dual piezoelectric wafer arm 463: Base 464a: Dual piezoelectric wafer arm / First dual piezoelectric wafer arm 464b: Dual piezoelectric wafer arm / Second dual piezoelectric wafer arm 466a: Friction component 466b: Friction component 467a: SMA line / First SMA line 467b: SMA line / Second SMA line 468a: Fixed end 468b: Fixed end 469a: First dual piezoelectric wafer arm 469b: Second bipiezoelectric chip 470: Unfixed, load point terminal 471: Flat surface 472: SMA line 473: Resistance Welding Zone 474: Radiation surface region 478: Nonlinear aperture 479: Partial Etching Tank 480: Control Input Pad 481: Grounding mat 482a: Dual piezoelectric wafer arm / First dual piezoelectric wafer arm 482b: Dual piezoelectric wafer arm / Second dual piezoelectric wafer arm 483a: Friction component 483b: Friction component 484a: Fixed end 484b: Fixed end 485a: SMA line 485b: SMA line 486: Polyimide layer 487: Control Input Pad 488: Grounding mat 489: Base 502: Sensor 504: z direction 506: Buckle Actuator 508: SMA line 510a to 510d: Depression 511: Outer shell 512a to 512d: Dual piezoelectric chip modules 514a to 514d: Dual piezoelectric chip actuators 516: Optical Image Stabilizing Housing 518a to 518d: Dual piezoelectric chip actuators 520a to 520d: Dual piezoelectric chip module 522a to 522d: Balance bracket / module, dual piezoelectric chip bracket / module 524: Image Sensor 526: Outer shell 528: Motion Image Sensor Bracket 530: Depression 532: Outer shell 534a to 534d: Dual Piezoelectric Chip Module 536: Metal outer casing, metal outer shell / shell 536a to 536d: Metal outer casing, metal outer casing / shell 538a to 538d: Molded Plastics 542a to 542d: Depression 570: Polyimide layer 571: Base 572: Control Input Pad 573: Grounding mat 574a: Dual piezoelectric wafer arm / First dual piezoelectric wafer arm 574b: Dual piezoelectric wafer arm / Second dual piezoelectric wafer arm 575a: Friction component 575b: Friction component 576a: First dual piezoelectric wafer arm 576b: Second dual piezoelectric wafer arm 577a: Dual Piezoelectric Crystal Arm 577b: Dual Piezoelectric Crystal Arm 578: SMA line 579: SMA line 604: Lens bracket 606: Wire Holder 608: Smart Memory Alloy ("SMA") Wire / Smart Memory Alloy ("SMA") Wire 610: Arm with buckle 612: Spring Arm 702: Sliding base 704: Assembly Base 706: Sliding bearing 708: Vertical sliding surface 710: Buckle Actuator 802: Buckle Actuator 804: Arm with buckle 806: Hammock Section 870: Unfixed, load point terminal 871: Flat surface 872: SMA line 873: Resistance Welding Zone 874: Radiation surface region 875: Proximal portion 876: Remote portion 893: Proximal aperture 894: Distal aperture 895: Fixed end 896: Flat surface 897: SMA line 898: Resistance Welding Area 902: Dual Piezoelectric Chip Actuator 904: Lens bracket 906: End 908: Base 1002: Autofocus Assembly 1004: Position Sensor 1005: z direction 1006: Moving Spring 1008: Magnet 1010: Lens bracket 1102a: Dual piezoelectric chip actuator 1102b: Dual piezoelectric chip actuator 1104a: Beam 1104b: Beam 1106b: SMA material, SMA tape 1108b: Adhesive film material 1110a: Contact element 1110b: Contact element 1110c: Contact element 1112b: 20-micron thick insulator 1112c: 20-micron thick insulator 1202: SMA material 1203a: End pad 1203b: End pad 1204: Center power supply 1206: Liang 1208: Central Metal 1210: Insulator 1212: Opening or through hole 1214a: Power Supply Section 1214b: Connecting to the next section 1216: Power supply contact components 1218: Grounding contact 1220: Surface coating 1222: Gap 1224: Through-hole section 1226: Through-hole section 1302: First buckle actuator 1304: Second buckle actuator 1306: Lens bracket 1308a: Hammock section 1308b: Hammock section 1310a: Arm with buckle 1310b: Arm with buckle 1312a: Arm with buckle 1312b: Arm with buckle 1314: Sliding base 1316: Sliding base 1318a: SMA line 1318b: SMA line 1512: Dual Piezoelectric Chip Actuator 1514: Liang 1516: SMA material / SMA tape or SMA wire 1518: Fixed end 1520: Load Point Terminal 1522: Press-fit part 1524: Press-fit part 1902: First buckle actuator 1904: Second belt buckle actuator 1906: Lens holder 1908a: Hammock section 1908b: Hammock section 1914: Sliding base 1916: Sliding base 1918: Base section 1920: Cover section 2202: First buckle actuator 2204: Second buckle actuator 2206: Lens bracket 2218a: Left SMA line 2218b: Right SMA line 2302: First buckle actuator 2304: Second buckle actuator 2305: Coupler Ring 2306: Lens bracket 2308a: Hammock section 2309b: Hammock section 2401: Sliding base 2402: Buckle Actuator 2403: Return spring 2404a to 2404d: Arm with buckle 2405: Lens bracket 2406: Lens bracket 2406a: Laminated Hammock 2406b: Laminated Hammock 2408a: SMA line 2408b: SMA line 2409: Shell 2412a to 2412d: Laminated press-fit connectors 2413: Pressed material 2414: Adapter Board 2415: Signal Trace 2501: SMA System 3000: Reinforcing component 3001a: Sliding base 3001b: Sliding base 3002: Buckle Actuator 3003: Return spring 3004a to 3004d: with buckle arm 3006: Lens bracket 3008a: SMA line 3008b: SMA line 3009a: Housing 3009b: Housing 3012a to 3012d: Resistance welding wire crimping materials 3014: Adapter Board 3020: Flexible Circuit 3022a: Electroplated pad 3022b: Electroplated pad 3101: SMA System 3501: SMA dual piezoelectric crystal liquid lens 3502: Liquid Lens Subassembly 3504: Housing 3506: SMA actuator 3508: Dual piezoelectric chip actuator 3510: Forming ring 3512: Flexible diaphragm 3514: Liquid 3516: Body containing ring 3518: Lens 3520: Contact element 3902: SMA actuator 3904: Positive Z-stroke actuator 3906: Negative Z-stroke actuator 3908: SMA line 3910: Lens bracket 3912: Top Spring 3914: Top spacer 3916: Bottom spacer 3918: Bottom Spring 3920: Base 4102: Length 4103: Dual piezoelectric crystal actuator 4104: Joint pad 4106: SMA line 4108: Extension Length 4202: SMA dual piezoelectric chip actuator 4302: Negative actuator signal connector 4304: Base 4306a: Dual piezoelectric chip actuator 4306b: Dual piezoelectric chip actuator 4308: Wire bonding pad 4310: Adhesive layer 4312b: SMA line 4314: Positive actuator signal connector 4316: Wire bonding pad 4318: Adhesive layer 4322: Connecting pad 4602: Flexible Sensor Circuit 4604: Dual piezoelectric crystal actuator circuit 4606: Dual piezoelectric chip actuator 4606a to 4606h: Dual piezoelectric chip actuator 4608: Mobile Bracket 4610: Outer shell 4802: SMA actuator 4804: Outer casing 5002: SMA actuator 5004: SMA dual piezoelectric chip actuator mounted on side 4 5202: Dual Piezoelectric Chip Actuator 5402: Bottom-mounted dual piezoelectric crystal actuator 5502: Top and bottom mounted SMA dual piezoelectric chip actuators 5802: SMA actuator / box-type dual piezoelectric chip actuator 5806: Dual piezoelectric chip actuator 5806a to 5806d: Dual piezoelectric chip actuators 6202: SMA actuator / box-type dual piezoelectric chip actuator 6204: Dual piezoelectric chip actuator 6204a to 6204h: Dual piezoelectric chip actuator 6504: Outer casing 6506: Lens bracket 6602: SMA actuator 6604: Dual piezoelectric crystal actuator / lens bracket 6604a to 6604h: Dual piezoelectric chip actuator 6802: SMA actuator / box-type dual piezoelectric chip actuator 6804: Sensor bracket 6806a to 6806d: Dual piezoelectric chip actuators 7402: SMA Actuator / Box-type Dual Piezoelectric Chip Actuator 7404: Dual piezoelectric crystal actuator 7404a to 7404d: Dual piezoelectric chip actuators 7902: SMA actuator 7904: Dual piezoelectric crystal actuator 8402: SMA actuator 8404: Dual piezoelectric chip actuator 8404a to 8404d: Dual piezoelectric chip actuators 8901: Lens System 8902: Folding Lens 8903a to 8903d: Lenses 8904: Spindle 8906: Transmission axis 9001: Lens System 9002a to 9002h: Liquid Lens 9004: Image Sensor 9100: Actuated Folding Lens 9102: Prism 9104: Actuator 9106: Dual piezoelectric chip actuator 9201: Dual Piezoelectric Crystal Arm 9202: Dual Piezoelectric Crystal Beam 9203: Forming offset 9204: Offset / Bending Plane Z-Offset 9206: Offset / Slot Width 9208: Length 9210: SMA band or SMA line 9212: Fixed end 9214: Load Point Terminal 9301: Dual Piezoelectric Crystal Arm 9302: Dual piezoelectric crystal beam 9303: Forming offset 9304: Limiter 9306: Unfixed, load point terminal 9308: SMA band or SMA line 9401: Dual Piezoelectric Crystal Arm 9402: Dual piezoelectric crystal beam 9403: Forming offset 9404: Limiter 9406: Base 9408: concave part 9410: Partial 9501: Dual Piezoelectric Crystal Arm 9502: Dual Piezoelectric Crystal Beam 9504: Forming offset 9506: SMA band or SMA line 9601a: Dual Piezoelectric Crystal Arm 9601b: Dual Piezoelectric Crystal Arm 9602a: Dual piezoelectric crystal beam 9602b: Dual Piezoelectric Crystal Optical Beam 9604a: Forming offset 9604b: Forming offset 9606a: SMA band or SMA line 9606b: SMA band or SMA line 9608: Base 9610: Dual piezoelectric crystal actuator 9612: Dual piezoelectric crystal actuator 9614: Dual Piezoelectric Chip Actuator 9701: Arm with buckle 9702: Beam section 9704a: Load Point Extension 9704b: Load Point Extension 9706a: End 9706b: End 9710a: Load Point 9710b: Point of Load 9712: SMA band or SMA line 9801: Arm with buckle 9802: Beam section 9804: Load Point 9810: Load Point Extension 9901: Dual Piezoelectric Crystal Arm 9902: Beam section 9904a: Load Point Extension 9904b: Load Point Extension 9906: SMA band or SMA line 9910a: End 9910b: End

Claims

1. An actuator comprising: A plurality of dual piezoelectric wafer arms are configured to reduce the net friction of one of the plurality of dual piezoelectric wafer arms. The plurality of dual piezoelectric wafer arms are arranged in a linear, mirror-oriented configuration. The linear, mirror-oriented configuration includes: a first dual piezoelectric wafer arm and a second dual piezoelectric wafer arm. The second dual piezoelectric wafer arm is arranged in a linear configuration with the first dual piezoelectric wafer arm such that a fixed end of the second dual piezoelectric wafer arm is adjacent to a fixed end of the first dual piezoelectric wafer arm, and a free end of the first dual piezoelectric wafer arm is disposed relative to a free end of the second dual piezoelectric wafer arm.

2. The actuator of claim 1, wherein each of the plurality of dual piezoelectric chip arms includes a shape memory alloy (SMA) wire, and the SMA wires attached to the plurality of dual piezoelectric chip arms are connected in series and configured to receive current from each SMA wire to control the actuation of the actuator.

3. The actuator of claim 1, wherein the first dual piezoelectric wafer arm is configured to have a frictional component in a direction parallel to a longitudinal axis of the actuator at one of its fixed ends, and the second dual piezoelectric wafer arm is configured to have a frictional component in a direction opposite to that of the first dual piezoelectric wafer arm to reduce the net total friction to zero.

4. The actuator of claim 1, comprising a single shape memory alloy wire having a first end and a second end, the first end of the shape memory alloy being coupled to a first bipiezoelectric chip arm of the plurality of bipiezoelectric chip arms and the second end of the shape memory alloy being coupled to a second bipiezoelectric chip arm of the plurality of bipiezoelectric chip arms.

5. The actuator of claim 1, wherein the first dual piezoelectric wafer arm is configured to have a frictional component in one direction of the fixed end of the first dual piezoelectric wafer arm parallel to the longitudinal axis of the first dual piezoelectric wafer arm, and the second dual piezoelectric wafer arm is configured to have a frictional component in one direction opposite to the first dual piezoelectric wafer arm to reduce the net total friction to zero.

Images