Shape memory alloy actuator and method thereof

Abstract

Shape memory alloy (SMA) systems suffer from system complexity, resulting in bulky systems that require a large footprint and significant height clearance. Furthermore, current systems have not been able to achieve a high Z-stroke range with a compact, low-profile footprint. [Solution] SMA actuators and related methods are described. One embodiment of the actuator includes a base, a plurality of bending arms, and at least a first shape memory alloy wire connected to a pair of the plurality of bending arms. Another embodiment of the actuator includes a base and at least one bimorph actuator comprising a shape memory alloy material. The bimorph actuator is mounted on the base.

Description

Technical Field

[0002] , , ,

[0003] , , , ,

[0001] Embodiments of the present invention relate to the field of shape memory alloy systems. More particularly, embodiments of the present invention relate to the field of shape memory alloy actuators and related methods.

Background Art

[0002] Shape memory alloy (SMA) systems have a movable assembly or structure that can be used in combination with, for example, a camera lens element as an autofocus drive device. These systems can be surrounded by structures such as screening cans. The movable assembly is supported by bearings such as a plurality of balls to move on a support assembly. A flexure element formed from a metal such as phosphor bronze or stainless steel has a movable plate and a flexure portion. The flexure portion extends between the movable plate and the stationary support assembly to enable movement of the movable assembly relative to the stationary support assembly and functions as a spring. The balls allow the movable assembly to move with little resistance. The movable assembly and the support assembly are connected by four shape memory alloy (SMA) wires extending between the assemblies. Each of the SMA wires has one end attached to the support assembly and the opposite end attached to the movable assembly. By applying an electrical drive signal to the SMA wires, the suspension is actuated. However, these types of systems are plagued by system complexity and, as a result, result in bulky systems that require a large installation area and a large clearance height. Further, current systems have not been able to provide a high Z-stroke range in a compact and low-profile installation area.

Summary of the Invention

Means for Solving the Problems

[0003] SMA actuators and related methods are described. One embodiment of the actuator includes a base, a plurality of buckle arms, and at least a first shape memory alloy wire connected to a pair of the plurality of buckle arms. Another embodiment of the actuator includes a base and at least one bimorph actuator comprising a shape memory alloy material. The bimorph actuator is mounted on the base.

[0004] Embodiments of the present invention are described in the accompanying drawings as examples, not as limitations, and in the drawings, similar reference numerals indicate similar elements. [Brief explanation of the drawing]

[0005] [Figure 1a] This shows a lens assembly including an SMA actuator configured as a distortion actuator according to one embodiment. [Figure 1b] An SMA actuator according to one embodiment is shown. [Figure 2] An SMA actuator according to one embodiment is shown. [Figure 3] An exploded view of an autofocus assembly including an SMA wire actuator according to one embodiment is shown. [Figure 4] An autofocus assembly including an SMA actuator according to one embodiment is shown. [Figure 5] An SMA actuator according to one embodiment, including a sensor, is shown. [Figure 6] The images show a top view and a side view of an SMA actuator configured as a distortion actuator according to one embodiment, which includes a lens carriage. [Figure 7] A side view of a section of an SMA actuator according to an embodiment is shown. [Figure 8] Multiple figures of one embodiment of a distortion actuator are shown. [Figure 9] A bimorph actuator according to one embodiment, equipped with a lens carriage, is shown. [Figure 10] A cutaway view of an autofocus assembly including an SMA actuator according to one embodiment is shown. [Figure 11a] Diagrams of bimorph actuators according to several embodiments are shown. [Figure 11b] Diagrams of bimorph actuators according to several embodiments are shown. [Figure 11c] Diagrams of bimorph actuators according to several embodiments are shown. [Figure 12] A diagram of one embodiment of a bimorph actuator according to one embodiment is shown. [Figure 13] This shows a cross-section of the end pad of a bimorph actuator according to one embodiment. [Figure 14] This shows a cross-section of the central supply pad of a bimorph actuator according to one embodiment. [Figure 15] An exploded view of an SMA actuator including two distortion actuators according to one embodiment is shown. [Figure 16] An SMA actuator including two distortion actuators according to one embodiment is shown. [Figure 17] A side view of an SMA actuator including two distortion actuators according to one embodiment is shown. [Figure 18] A side view of an SMA actuator including two distortion actuators according to one embodiment is shown. [Figure 19] This shows an exploded view of an assembly including an SMA actuator with two distortion actuators according to one embodiment. [Figure 20] An SMA actuator including two distortion actuators according to one embodiment is shown. [Figure 21] An SMA actuator including two distortion actuators according to one embodiment is shown. [Figure 22] An SMA actuator including two distortion actuators according to one embodiment is shown. [Figure 23] An SMA actuator including two distortion actuators and a coupler according to one embodiment is shown. [Figure 24] Shows a developed view of a SMA system including a SMA actuator including a distortion actuator with a laminated plate hammock according to an embodiment. [Figure 25] Shows a SMA system including a SMA actuator including a distortion actuator 2402 with a laminated plate hammock according to an embodiment. [Figure 26] Shows a distortion actuator including a laminated plate hammock according to an embodiment. [Figure 27] Shows a laminated plate hammock of a SMA actuator according to an embodiment. [Figure 28] Shows a pressure-bonded connection part formed by laminating a SMA actuator according to an embodiment. [Figure 29] Shows a SMA actuator including a distortion actuator with a laminated plate hammock. [Figure 30] Shows a developed view of a SMA system including a SMA actuator including a distortion actuator according to an embodiment. [Figure 31] Shows a SMA system including a SMA actuator including a distortion actuator according to an embodiment. [Figure 32] Shows a SMA actuator including a distortion actuator according to an embodiment. [Figure 33] Shows a two-yoke capture joint of a pair of distortion arms of a SMA actuator according to an embodiment. [Figure 34] Shows a resistance welding pressure-bonded part of a SMA actuator used to attach a SMA wire to a distortion actuator according to an embodiment. [Figure 35] Shows a SMA actuator including a distortion actuator with a two-yoke capture joint. [Figure 36] Shows a SMA bimorph liquid lens according to an embodiment. [Figure 37] Shows a perspective SMA bimorph liquid lens according to an embodiment. [Figure 38]A cross-sectional and bottom view of an SMA bimorph liquid lens according to one embodiment are shown. [Figure 39] An SMA system including an SMA actuator equipped with a bimorph actuator, according to one embodiment, is shown. [Figure 40] This shows an SMA actuator equipped with a bimorph actuator according to one embodiment. [Figure 41] This shows the length of the bimorph actuator and the location of the bonding pads for the SMA wire, in order to extend the wire length beyond the bimorph actuator. [Figure 42] This shows an exploded view of an SMA system including a bimorph actuator according to one embodiment. [Figure 43] This shows an exploded view of a sub-section of an SMA actuator according to one embodiment. [Figure 44] A sub-section of an SMA actuator according to one embodiment is shown. [Figure 45] This shows a 5-axis sensor shift system according to one embodiment. [Figure 46] This shows an exploded view of a 5-axis sensor shift system according to one embodiment. [Figure 47] This shows an SMA actuator, including a bimorph actuator, which is incorporated into this circuit for all of its movements, according to one embodiment. [Figure 48] This shows an SMA actuator, including a bimorph actuator, which is incorporated into this circuit for all of its movements, according to one embodiment. [Figure 49] This shows a cross-section of a 5-axis sensor shift system according to one embodiment. [Figure 50] An SMA actuator according to one embodiment, including a bimorph actuator, is shown. [Figure 51] A top view of an SMA actuator according to one embodiment is shown, which includes a bimorph actuator in which an image sensor is moved to different x and y positions. [Figure 52]This shows an SMA actuator including a bimorph actuator according to one embodiment, configured as a box bimorph autofocus. [Figure 53] This shows an SMA actuator including a bimorph actuator according to one embodiment. [Figure 54] This shows an SMA actuator including a bimorph actuator according to one embodiment. [Figure 55] This shows an SMA actuator including a bimorph actuator according to one embodiment. [Figure 56] This shows an SMA system including an SMA actuator according to one embodiment, which includes a bimorph actuator. [Figure 57] This diagram shows an exploded view of an SMA system including an SMA actuator according to one embodiment, which includes a bimorph actuator configured as a two-axis lens-shift OIS. [Figure 58] This shows a cross-section of an SMA system including an SMA actuator according to one embodiment, which includes a bimorph actuator configured as a two-axis lens-shift OIS. [Figure 59] A box-bimorph actuator according to one embodiment is shown. [Figure 60] This shows an SMA system including an SMA actuator according to one embodiment, which includes a bimorph actuator. [Figure 61] This diagram shows an exploded view of an SMA system including an SMA actuator according to one embodiment, which includes a bimorph actuator. [Figure 62] This shows a cross-section of an SMA system including an SMA actuator according to one embodiment, which includes a bimorph actuator. [Figure 63] A box-bimorph actuator according to one embodiment is shown. [Figure 64] This shows an SMA system including an SMA actuator according to one embodiment, which includes a bimorph actuator. [Figure 65]This diagram shows an exploded view of an SMA system including an SMA actuator according to one embodiment, which includes a bimorph actuator. [Figure 66] This shows an SMA system including an SMA actuator according to one embodiment, which includes a bimorph actuator. [Figure 67] This shows an SMA system including an SMA actuator according to one embodiment, which includes a bimorph actuator. [Figure 68] This shows an SMA system including an SMA actuator according to one embodiment, which includes a bimorph actuator. [Figure 69] This diagram shows an exploded view of an SMA including an SMA actuator according to one embodiment, which includes a bimorph actuator. [Figure 70] This shows a cross-section of an SMA system including an SMA actuator according to one embodiment, which includes a bimorph actuator configured as a 3-axis sensor-shift OIS. [Figure 71] A box-bimorph actuator component according to one embodiment is shown. [Figure 72] A flexible sensor circuit for use in an SMA system according to one embodiment is shown. [Figure 73] This shows an SMA system including an SMA actuator according to one embodiment, which includes a bimorph actuator. [Figure 74] This diagram shows an exploded view of an SMA system including an SMA actuator according to one embodiment, which includes a bimorph actuator. [Figure 75] A cross-section of an SMA system including an SMA actuator according to one embodiment is shown. [Figure 76] A box-bimorph actuator according to one embodiment is shown. [Figure 77] A flexible sensor circuit for use in an SMA system according to one embodiment is shown. [Figure 78] This shows an SMA system including an SMA actuator according to one embodiment, which includes a bimorph actuator. [Figure 79]This diagram shows an exploded view of an SMA system including an SMA actuator according to one embodiment, which includes a bimorph actuator. [Figure 80] A cross-section of an SMA system including an SMA actuator according to one embodiment is shown. [Figure 81] A box-bimorph actuator according to one embodiment is shown. [Figure 82] A flexible sensor circuit for use in an SMA system according to one embodiment is shown. [Figure 83] This shows an SMA system including an SMA actuator according to one embodiment, which includes a bimorph actuator. [Figure 84] This shows an exploded view of an SMA system including an SMA actuator according to one embodiment. [Figure 85] This shows a cross-section of an SMA system including an SMA actuator according to one embodiment, which includes a bimorph actuator. [Figure 86] A box-bimorph actuator for use in an SMA system according to one embodiment is shown. [Figure 87] A flexible sensor circuit for use in an SMA system according to one embodiment is shown. [Figure 88] Exemplary dimensions of bimorph actuators of SMA actuators according to multiple embodiments are shown. [Figure 89] This shows a lens system for a foldable camera according to one embodiment. [Figure 90] Several embodiments of a lens system including a liquid lens according to one embodiment are shown. [Figure 91] This shows a bending lens, which is a prism, placed in an actuator according to one embodiment. [Figure 92] This shows a bimorph arm with an offset according to one embodiment. [Figure 93] A bimorph arm equipped with an offset and limiter according to one embodiment is shown. [Figure 94]A bimorph arm equipped with an offset and limiter according to one embodiment is shown. [Figure 95] An embodiment of a base including an offset bimorph arm according to one embodiment is shown. [Figure 96] An embodiment of a base including two offset bimorph arms according to one embodiment is shown. [Figure 97] This shows a curved arm including a load point extension according to one embodiment. [Figure 98] A curved arm 9801 including a load point extension 9810 according to one embodiment is shown. [Figure 99] A bimorph arm including a load point extension according to one embodiment is shown. [Figure 100] A bimorph arm including a load point extension according to one embodiment is shown. [Figure 101] This shows an SMA optical image stabilization mechanism according to one embodiment. [Figure 102] This shows the SMA material mounting portion 40 of the movable part according to one embodiment. [Figure 103] This shows the SMA mounting portion of a stationary plate to which resistance-welded SMA wires are attached, according to one embodiment. [Figure 104] An SMA actuator 45 including a distortion actuator according to one embodiment is shown. [Figure 105a] This shows a resistance welding crimp section including an island for an SMA actuator according to one embodiment. [Figure 105b] This shows a resistance welding crimp section including an island for an SMA actuator according to one embodiment. [Figure 106] This shows the relationship between the z-offset of the bending surface, the trough width, and the peak force of a bimorph beam according to one embodiment. [Figure 107] This example shows how the box volume, which is an approximation of the box containing the entire bimorph actuator according to one embodiment, relates to the amount of work per bimorph component. [Figure 108] This shows a liquid lens operated using a distortion actuator according to one embodiment. [Figure 109] This shows an unfixed load-point end of a bimorph arm according to one embodiment. [Figure 110] This shows an unfixed load-point end of a bimorph arm according to one embodiment. [Figure 111] This shows an unfixed load-point end of a bimorph arm according to one embodiment. [Figure 112] This shows an unfixed load-point end of a bimorph arm according to one embodiment. [Figure 113] This shows the fixed end of a bimorph arm according to one embodiment. [Figure 114] This shows the fixed end of a bimorph arm according to one embodiment. [Figure 115] This shows the fixed end of a bimorph arm according to one embodiment. [Figure 116] This shows the fixed end of a bimorph arm according to one embodiment. [Figure 117] This shows a rear view of the fixed end of a bimorph arm according to one embodiment. [Figure 118] This shows an unfixed load-point end of a bimorph arm according to one embodiment. [Figure 119] An alternative embodiment shows an unfixed load-point end of a bimorph arm. [Figure 120] An alternative embodiment shows an unfixed load-point end of a bimorph arm. [Figure 121] An alternative embodiment shows an unfixed load-point end of a bimorph arm. [Figure 122] An alternative embodiment shows an unfixed load-point end of a bimorph arm. [Figure 123] This shows the fixed load-point end of a bimorph arm according to one embodiment. [Figure 124] This shows the fixed load-point end of a bimorph arm according to one embodiment. [Figure 125] This shows the fixed load-point end of a bimorph arm according to one embodiment. [Figure 126] An alternative embodiment shows a fixed load-point end of a bimorph arm. [Modes for carrying out the invention]

[0006] Embodiments of SMA actuators are described herein, which include a compact footprint and provide a high working height, e.g., movement, in the positive z-axis direction (z-direction), referred herein to as z-stroke. Embodiments of SMA actuators include SMA distortion actuators and SMA bimorph actuators. SMA actuators can be used in many applications, such as, but are not limited to, lens assemblies as autofocus actuators, micro-fluidic pumps, sensor shifts, optical image stabilization, and optical zoom assemblies, to mechanically strike two surfaces to produce a vibration sensation, as is commonly found in tactile feedback sensors and devices, and in other systems in which actuators are used. For example, embodiments of actuators described herein can be used as tactile feedback actuators for use in cellular mobile phones and wearable devices, configured to provide the user with an alarm, notification, warning, touched area, or button press response. Furthermore, two or more SMA actuators may be used in a system to achieve a larger stroke.

[0007] In various embodiments, the SMA actuator has a z-stroke greater than 4 millimeters. Furthermore, the SMA actuator for various embodiments has a height of 2.2 millimeters or less in the z-direction when the SMA actuator is in its initial stop position. Various embodiments of the SMA actuator configured as an autofocus actuator in a lens assembly may have a small footprint that is about 3 millimeters larger than the inner diameter (ID) of the lens. According to various embodiments, the SMA actuator may have a footprint that is wide in one direction to accommodate components including, but not limited to, sensors, wires, traces, and connectors. According to some embodiments, the footprint of the SMA actuator is 0.5 millimeters larger in one direction; for example, the length of the SMA actuator is 0.5 millimeters longer than its width.

[0008] Figure 1a shows a lens assembly including an SMA actuator configured as a distortion actuator according to one embodiment. Figure 1b shows an SMA actuator configured as a distortion actuator according to one embodiment. The distortion actuator 102 is connected to a base 101. As shown in Figure 1b, an SMA wire 100 is attached to the distortion actuator 102, and when the SMA wire 100 is actuated and contracted, it causes the distortion actuator 102 to bend, so that at least the center 104 of each distortion actuator 102 moves in the z-stroke direction, for example in the positive z direction as indicated by arrow 108. According to some embodiments, the SMA wire 100 is actuated when current is supplied to one end of the wire through a wire holder such as a crimping structure 106. The current flows through the SMA wire 100 and heats the SMA wire due to the inherent resistance of the SMA material from which the SMA wire 100 is made. The other end of the SMA wire 100 has a wire holder such as a crimp structure 106, which connects the SMA wire 100 to ground to complete the circuit. Heating the SMA wire 100 to a sufficient temperature changes the crystalline structure from martensite to austenite due to the wire's inherent material properties, thereby changing the length of the wire. Changing the current changes the temperature and therefore the length of the wire, which is used to activate or deactivate the actuator in order to control the actuator's movement, at least in the z direction. Those skilled in the art will understand that other techniques may be used to supply current to the SMA wire.

[0009] Figure 2 shows an SMA actuator configured as an SMA bimorph actuator according to one embodiment. As shown in Figure 2, the SMA actuator includes a bimorph actuator 202 connected to a base 204. The bimorph actuator 202 includes an SMA ribbon 206. The bimorph actuator 202 is configured to move at least one unfixed end of the bimorph actuator 202 in the z-stroke direction 208 when the SMA ribbon 206 is retracted.

[0010] Figure 3 shows an exploded view of an autofocus assembly including an SMA actuator according to one embodiment. As shown, the SMA actuator 302 is configured as a distortion actuator according to one of the embodiments described herein. The autofocus assembly also includes an optical image stabilization (OIS) 304, a lens carriage 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 cover 312. When the SMA wire is actuated and the distortion actuator 302 is pulled and flexed using techniques including those described herein, the SMA actuator 302 moves in the z-stroke direction, for example in the positive z-direction, so that the lens carriage 306 slides in contact with the vertical sliding bearing nmg 310. The return spring 308 is configured to apply force on the lens carriage 306 in the opposite direction to the stroke direction using techniques including those known in the art. According to various embodiments, the return spring 308 is configured to move the lens carriage 306 in the opposite direction to the z-stroke when the tension of the SMA wire is reduced so that the SMA wire stops operating. When the tension of the SMA wire is reduced to its initial value, the lens carriage 306 moves to its lowest height in the z-stroke direction. Figure 4 shows an autofocus assembly including an SMA wire actuator according to one embodiment shown in Figure 3.

[0011] Figure 5 shows an SMA wire actuator according to one embodiment, including a sensor. In various embodiments, the sensor 502 is configured to measure the movement of the SMA actuator in the z direction, or the movement of the component on which the SMA actuator is moving, using techniques including those known in the art. The SMA actuator includes one or more distortion actuators 506 configured to operate using one or more SMA wires 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 carriage 306 from its initial position in the z direction 504, using techniques including those known in the art. According to some embodiments, the sensor is a tunnel magnetoresistive (TMR) sensor.

[0012] Figure 6 shows a top and side view of an SMA actuator 602 configured as a distortion actuator according to one embodiment, with a lens carriage 604 mounted on it. Figure 7 shows a side view of a section of the SMA actuator 602 according to the embodiment shown in Figure 6. According to the embodiment shown in Figure 7, the SMA actuator 602 includes a slide base 702. According to one embodiment, the slide base 702 is formed of a metal such as stainless steel using techniques including those known in the art. However, those skilled in the art will understand that other materials may be used to form the slide base 702. Furthermore, according to some embodiments, the slide base 702 has a spring arm 612 connected to the SMA actuator 602. According to various embodiments, the spring arm 612 is configured to perform two functions. The first function is to help push an object, such as the lens carriage 604, onto the vertical sliding surface of the guide cover. In this example, the spring arm 612 pre-loads the lens carriage 604 upward and presses it onto this surface, ensuring that the lens does not tilt during operation. In some embodiments, the vertical sliding surface 708 is configured to engage with a guide cover. A second function of the spring arm 612 is to help the SMA wire 608 pull and retract the SMA actuator 602 after it has moved in the z-stroke direction, in the positive z-direction, for example, in the negative z-direction. Thus, when the SMA wire 608 is actuated, they contract to move the SMA actuator 602 in the z-stroke direction, and when the SMA wire 608 is deactivated, the spring arm 612 is configured to move the SMA actuator 602 in the opposite direction to the z-stroke direction.

[0013] The SMA actuator 602 also includes a bending actuator 710. In various embodiments, the bending actuator 710 is formed of a metal such as stainless steel. Furthermore, the bending actuator 710 includes a bending arm 610 and one or more wire holders 606. According to the embodiments shown in Figures 6 and 7, the bending actuator 710 includes four wire holders 606. Each of the four wire holders 606 is configured to receive the end of an SMA wire 608 and hold that end of the SMA wire 608 so that the SMA wire 608 can be attached to the bending actuator 710. In various embodiments, the four wire holders 606 are crimping parts configured to tightly fasten a portion of the SMA wire 608 so that the wire can be attached to the crimping part. Those skilled in the art will understand that the SMA wire 608 may be attached to the wire holders 606 using techniques known in the art, for example, adhesives, soldering, and mechanical attachments, but not limited to these. A smart memory alloy (SMA) wire 608 extends between a pair of wire holders 606, and when the SMA wire 608 is actuated, the deformation arm 610 of the deformation actuator 710 moves, causing the pair of wire holders 606 to be pulled closer to each other. According to various embodiments, the SMA wire 608 is electrically actuated to move and control the position of the deformation arm 610 when current is passed through the SMA wire 608. The SMA wire 608 is deactivated when the current is removed or falls below a threshold. This moves the pair of wire holders 606 apart, and when the SMA wire 608 is actuated, the deformation arm 610 moves in the opposite direction. According to various embodiments, the deformation arm 610 is configured to have an initial angle of 5 degrees relative to the slide base 702 when the SMA wire is deactivated in its initial position. Furthermore, according to various embodiments, the bending arm 610 is configured to have a 10-12 degree angle relative to the slide base 702 when in full stroke or when the SMA wire is fully actuated.

[0014] According to the embodiments shown in Figures 6 and 7, the SMA actuator 602 also includes a sliding bearing 706 configured between the slide base 702 and the wire holder 606. The sliding bearing 706 is configured to minimize any friction between the slide base 702 and the bending arm 610 and / or the wire holder 606. For some embodiments, the sliding bearing is mounted on the sliding bearing 706. According to various embodiments, the sliding bearing is formed of polyoxymethylene (POM). Those skilled in the art will understand that other structures may be used to reduce any friction between the bending actuator and the base.

[0015] According to various embodiments, the slide base 702 is configured to connect to an assembly base 704, for example, an autofocus base for an autofocus assembly. According to some embodiments, the actuator base 704 includes an etched shim. Such an etched shim may be used to provide clearance between the wire and the crimp when the SMA actuator 602 is part of an assembly, for example, an autofocus assembly.

[0016] Figure 8 shows multiple diagrams of one embodiment of the distortion actuator 802 with respect to the x, y, and z axes. As oriented in Figure 8, the distortion arm 804 is configured to move along the z axis when the SMA wire is operated or deactivated as described herein. According to the embodiment shown in Figure 8, the distortion arms 804 are connected to each other by a central part such as a hammock section 806. According to various embodiments, the hammock section 806 is configured to support a lens carriage moved by the distortion actuator using a technique including, for example, those described herein, on a portion of the object on which the distortion actuator acts. According to some embodiments, the hammock section 806 is configured to provide lateral stiffness to the distortion actuator during operation. With regard to other embodiments, the distortion actuator does not include a hammock section 806. According to these embodiments, the distortion arm is configured to act on an object to move it. For example, the distortion arm is configured to act directly on a feature of the lens carriage to push it upward.

[0017] Figure 9 shows an SMA actuator configured as an SMA bimorph actuator according to one embodiment. The SMA bimorph actuator includes a bimorph actuator 902, including those described herein. According to the embodiment shown in Figure 9, one end 906 of each bimorph actuator 902 is attached to a base 908. According to some embodiments, one end 906 is welded to the base 908. However, those skilled in the art will understand that other techniques may be used to attach one end 906 to the base 908. Figure 9 also shows a lens carriage 904 positioned such that the bimorph actuator 902 curves in the z direction when operated, lifting the carriage 904 in the z direction. In some embodiments, a return spring is used to push the bimorph actuator 902 back to its initial position. The return spring may be configured to assist in pushing the bimorph actuator down to its initial deactivation position, as described herein. Because of the small footprint of the bimorph actuator, SMA actuators can be manufactured with a smaller footprint than current actuator technology.

[0018] Figure 10 shows a cutaway view of an autofocus assembly including an SMA actuator according to one embodiment, including a position sensor, such as a TMR sensor. The autofocus assembly 1002 includes a position sensor 1004 attached to a movable spring 1006 and a magnet 1008 attached to the lens carriage 1010 of the autofocus assembly, which includes an SMA actuator such as one described herein. The position sensor 1004 is configured to determine the amount by which the lens carriage 1010 moves from its initial position in the z direction 1005, based on the distance of the magnet 1008 from the position sensor 1004, using techniques including those known in the art. According to some embodiments, the position sensor 1004 is electrically connected to a controller or processor, such as a central processing unit, using multiple electrical traces on the spring arm of the movable spring 1006 of the optical image stabilization mechanism assembly.

[0019] Figures 11a to 11c show diagrams of bimorph actuators according to several embodiments. According to various embodiments, the bimorph actuator 1102 includes a beam 1104 and one or more SMA materials 1106, for example, an SMA ribbon 1106b (as shown in the perspective view of the bimorph actuator including an SMA ribbon according to the embodiment of Figure 11b) or an SMA wire 1106a (as shown in the cross-sectional view of the bimorph actuator including an SMA wire according to the embodiment of Figure 11a). The SMA materials 1106 are attached to the beam 1104 using techniques including those described herein. According to some embodiments, the SMA materials 1106 are attached to the beam 1104 using an adhesive film material 1108. With respect to various embodiments, the ends of the SMA materials 1106 are electrically and mechanically connected to contacts 1110 configured to supply current to the SMA materials 1106 using techniques including those known in the art. According to various embodiments, the contact 1110 (for example, as shown in Figures 11a and 11b) is a gold-plated copper pad. According to several embodiments, a bimorph actuator 1102 having a length of approximately 1 millimeter is configured to produce a larger stroke and a pressing force of 50 millinewtons (mN), and is used as part of a lens assembly, as shown, for example, in Figure 11c. According to some embodiments, the use of a bimorph actuator 1102 having a length greater than 1 millimeter produces a larger stroke than that of a 1-millimeter length, but produces a weaker force. In one embodiment, the bimorph actuator 1102 includes a 20-micrometer thick SMA material 1106, a 20-micrometer thick insulator 1112, such as a polyimide insulator, and a 30-micrometer thick stainless steel beam 1104, i.e., a base metal. Various embodiments include a second insulator 1114 placed between the contact layer containing the contact 1110 and the SMA material 1106. According to some embodiments, the second insulator 1114 is configured to insulate the SMA material 1106 from the portion of the contact layer that is not used as the contact 1110.In some embodiments, the second insulator 1114 is a cover coat layer such as a polyimide insulator. Those skilled in the art will understand that other dimensions and materials may be used to satisfy desired design characteristics.

[0020] Figure 12 shows a diagram of one embodiment of a bimorph actuator according to one embodiment. The embodiment shown in Figure 12 includes a central power supply unit 1204 for supplying power. Power is supplied to the center of an SMA material 1202 (wire or ribbon), such as those described herein. The ends of the SMA material 1202 are grounded to a beam 1206, i.e., a base metal, as a return path at an end pad 1203. The end pad 1203 is electrically insulated from the rest of the contact layer 1214. According to several embodiments, the beam 1206, i.e., the base metal, is in close proximity to the SMA material 1202 along its entire length, such as an SMA wire, so that when the current is turned off, i.e., when the bimorph actuator stops, the wire cools more quickly. This results in faster wire deactivation and actuator response time. The thermal profile of the SMA wire or ribbon is improved. For example, the thermal profile becomes more uniform, and a larger total current can be reliably supplied to the wire. Without a uniform heat sink, multiple parts of the wire, such as the central region, can overheat and be damaged; therefore, reduced current and reduced movement are required for reliable operation. The central power supply 1204 benefits from faster wire activation / operation (faster heating) and reduced power consumption (lower resistance path length) of the SMA material 1202 for faster response times. This enables faster actuator movement and capability for operation at higher movement frequencies.

[0021] As shown in Figure 12, the beam 1206 includes a central metal 1208, which is insulated from the rest of the beam 1206 to form a central power supply section 1204. An insulator 1210, such as those described herein, is positioned to cover the upper side of the beam 1206. The insulator 1210 is configured to have one or more openings or vias 1212 to provide electrical access to the beam 1206, for example, to a grounding section 1214b of a contact layer, and to provide contact to the central metal 1208 to form the central power supply section 1204. According to some embodiments, a contact layer 1214, such as those described herein, includes a power section 1214a and a grounding section 1214b, and provides actuation / control signals to a bimorph actuator via power supply contacts 1216 and grounding contacts 1218. A cover coat layer 1220, such as those described herein, is positioned to cover the upper side of the contact layer 1214, thereby electrically insulating the contact layer except for several portions of the contact layer 1214 (e.g., one or more contacts) where electrical connection is desired.

[0022] Figure 13 shows a cross-section of the end pad of a bimorph actuator according to one embodiment, as shown in Figure 12. As described above, the end pad 1203 is electrically insulated from the rest 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 etching techniques, including those known in the art. The end pad 1203 includes a via section 1224 configured to electrically connect the end pad 1203 to the beam 1206. The via section 1224 is formed in vias 1212 formed in the insulator 1210. The SMA material 1202 is electrically connected to the end pad 1213. The SMA material 1202 may be electrically connected to the end pad 1213 using techniques including, but not limited to, soldering, resistance welding, laser welding, and direct plating.

[0023] Figure 14 shows a cross-section of the central power supply section of a bimorph actuator according to one embodiment, as shown in Figure 12. The central power supply section 1204 is electrically connected to a power supply device through a contact layer 1214, and is electrically and thermally connected to the central metal 1208 by via sections 1226 located in the central power supply section 1204 and formed in vias 1212 formed in the insulator 1210.

[0024] The actuators described herein may be used to form actuator assemblies using multiple distortion actuators and / or multiple bimorph actuators. According to one embodiment, the actuators may be stacked in an overlapping manner to increase the stroke distance that can be achieved.

[0025] Figure 15 shows an exploded view of an SMA actuator including two distortion actuators according to one embodiment. According to several embodiments described herein, the two distortion actuators 1302 and 1304 are positioned relative to each other to use their opposing movements. With regard to various embodiments, the two distortion actuators 1302 and 1304 are configured to move in opposite directions relative to each other in order to position the lens carriage 1306. For example, the first distortion actuator 1302 is configured to receive an inverse power signal of the power signal sent to the second distortion actuator 1304.

[0026] Figure 16 shows an SMA actuator including two distortion actuators according to one embodiment. The distortion actuators 1302 and 1304 are configured such that the distortion arms 1310 and 1312 of each distortion actuator 1302 and 1304 face each other, and the slide bases 1314 and 1316 of each distortion actuator 1302 and 1304 are the outer surfaces of the two distortion actuators. According to various embodiments, the hammock portion 1308 of each SMA actuator 1302 and 1304 is configured to support a portion of a lens carriage 1306 that is moved by the distortion actuators using an object on which one or more distortion actuators 1302 and 1304 act, including techniques described herein.

[0027] Figure 17 shows a side view of an SMA actuator including two distortion actuators according to one embodiment, indicating the direction of the SMA wire 1318 that moves an object such as a lens carriage in the positive z direction or upward direction.

[0028] Figure 18 shows a side view of an SMA actuator including two distortion actuators according to one embodiment, indicating the direction of the SMA wire 1318 that moves an object such as a lens carriage in the negative z direction or downward.

[0029] Figure 19 shows an exploded view of an assembly including an SMA actuator with two distortion actuators according to one embodiment. The distortion actuators 1902, 1904 are configured such that the distortion arms 1910, 1912 of each distortion actuator 1902, 1904 are the outer surfaces of the two distortion actuators, and the slide bases 1914, 1916 of each distortion actuator 1902, 1904 face each other. According to various embodiments, the hammock portion 1908 of each SMA actuator 1902, 1904 is configured to support a portion of a lens carriage 1906 moved by the distortion actuators using an object on which one or more distortion actuators 1902, 1904 act, including techniques described herein. With respect to some embodiments, the SMA actuator includes a base portion 1918 configured to receive a second distortion actuator 1904. The SMA actuator may also include a cover portion 1920. Figure 20 shows an SMA actuator including two distortion actuators according to one embodiment, including a base portion and a cover portion.

[0030] Figure 21 shows an SMA actuator comprising two distortion actuators according to one embodiment. In some embodiments, the distortion actuators 1902 and 1904 are positioned relative to each other such that the hammock portion 1908 of the first distortion actuator 1902 is rotated approximately 90 degrees from the hammock portion of the second distortion actuator 1904. The 90-degree configuration allows for pitch and roll rotation of an object such as a lens carriage 1906. This allows for better control of the movement of the lens carriage 1906. In various embodiments, differential power signals are supplied to the SMA wires of each pair of distortion actuators to provide pitch and roll rotation of the lens carriage to produce a tilt in the movement of the OIS.

[0031] Embodiments of an SMA actuator including two distortion actuators eliminate the need for a return spring. The use of two distortion actuators can improve / reduce hysteresis when using SMA wire resistance for position feedback. An SMA actuator including two distortion actuators that generate opposing forces assists in more precise position control due to lower hysteresis than one including a return spring. In some embodiments, for example, the embodiment shown in Figure 22, an SMA actuator including two distortion actuators 2202, 2204 uses differential power to the left and right SMA wires 2218a, 2218b of each distortion actuator 2202, 2204 to produce a two-axis tilt. For example, the left SMA wire 2218a is actuated with higher power than the right SMA wire 2218b. This moves the left side of the lens carriage 2206 downward and the right side upward (tilts it). The SMA wires of the first distortion actuator 2202 are held with equal force and, in some embodiments, serve as fulcrums for the SMA wires 2218a, 2218b to push differently to cause a tilting motion. By reversing the power signals supplied to the SMA wires, for example, supplying equal power to the SMA wires of the second distortion actuator 2202, and by using differential power to the left and right SMA wires 2218a, 2218b of the second distortion actuator 2204, a tilt of the lens carriage 2206 in the other direction is produced. This provides the ability to tilt an object such as a lens carrier on either axis of motion, or to adjust any tilt between the lens and the sensor for good dynamic tilt, thereby resulting in better image quality across all pixels.

[0032] Figure 23 shows an SMA actuator comprising two distortion actuators and a coupler according to one embodiment. The SMA actuator includes two distortion actuators, such as those described herein. The first distortion actuator 2302 is configured to connect to the second distortion actuator 2304 using a coupler, for example, a coupler ring 2305. The distortion actuators 2302 and 2304 are positioned relative to each other such that the hammock portion 2308 of the first distortion actuator 2302 is rotated approximately 90 degrees from the hammock portion 2309 of the second distortion actuator 2304. A payload to be moved, such as a lens or lens assembly, is mounted on a lens carriage 2306 configured to be positioned on the slide base of the first distortion actuator 2302.

[0033] In various embodiments, equal power can be supplied to the SMA wires of the first and second distortion actuators 2302 and 2304. This can maximize the z-stroke of the SMA actuators in the positive z-direction. In some embodiments, the stroke of an SMA actuator may have a z-stroke equal to or equal to twice the stroke of another SMA actuator, including two distortion actuators. In some embodiments, additional springs can be added to the two distortion sections to help push the actuator assembly and payload downward when the power signal is removed from the SMA actuators. Equal and opposite power signals are applied to the SMA wires of the first and second distortion actuators 2302 and 2304. This allows the SMA actuators to be moved in the positive z-direction by one distortion actuator and in the negative z-direction by the other distortion actuator, thereby enabling precise control of the position of the SMA actuators. Furthermore, equal and opposite power signals (differential power signals) are applied to the left and right SMA wires of the first distortion actuator 2302 and the second distortion actuator 2304, causing an object such as a lens carriage 2306 to tilt in the direction of at least one of the two axes.

[0034] Embodiments of an SMA actuator, such as that shown in Figure 23, which include two distortion actuators and a coupler, can be connected to additional distortion actuators and multiple pairs of distortion actuators to achieve a larger desired stroke than that of a single SMA actuator.

[0035] Figure 24 shows an exploded view of an SMA system including an SMA actuator with a distortion actuator comprising a laminated plate hammock according to one embodiment. In some embodiments as described herein, the SMA system is configured to be used in conjunction with one or more camera lens elements as an autofocus drive. As shown in Figure 24, according to various embodiments, the SMA system includes a return spring 2403 configured to move the lens carriage 2406 in the opposite direction to the z-stroke when the tension of the SMA wire 2408 is reduced so that the SMA wire is deactivated. In some embodiments, the SMA system includes a housing 2409, which is configured to receive the return spring 2403 and act as a sliding bearing to guide the lens carriage in the z-stroke direction. The housing 2409 is also configured to be located on the distortion actuator 2402. The distortion actuator 2402 includes a slide base 2401 similar to those described herein. The distortion actuator 2402 includes a distortion arm 2404 connected to a hammock section, for example, a laminated hammock 2406 formed of laminated boards. The distortion actuator 2402 also includes an SMA wire mounting structure, such as a laminated crimp connector 2412.

[0036] As shown in Figure 24, the slide base 2401 is positioned on an optional adapter plate 2414. The adapter plate is configured to mate the SMA system or the distortion actuator 2402 with another system, such as an OIS, an additional SMA system, or other components. Figure 25 shows an SMA system 2501 including an SMA actuator, which includes a distortion actuator 2402 with a laminated plate hammock according to one embodiment.

[0037] Figure 26 shows a distortion actuator including a laminated hammock according to one embodiment. The distortion actuator 2402 includes a distortion arm 2404. As described herein, the distortion arm 2404 is configured to move along the z-axis when an SMA wire 2412 is activated or deactivated. The SMA wire 2408 is attached to the distortion actuator using a laminated crimped connection 2412. According to the embodiment shown in Figure 26, the distortion arms 2404 are connected to each other by a central part, for example, a laminated hammock 2406. According to various embodiments, the laminated hammock 2406 is configured to support an object on which the distortion actuator acts, for example, a portion of a lens carriage moved by the distortion actuator using techniques including those described herein.

[0038] Figure 27 shows a laminated hammock of an SMA actuator according to one embodiment. In some embodiments, the material of the laminated hammock 2406 is a low-rigidity material and therefore does not resist the movement of the operation. For example, the laminated hammock 2406 is formed using a copper layer placed on a first polyimide layer, with a second polyimide layer placed on the copper. In some embodiments, the laminated hammock 2406 is formed on the bending arm 2404 using deposition and etching, using techniques including those known in the art. In other embodiments, the laminated hammock 2406 is formed separately from the bending arm 2404 and attached to the bending 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 bending arm 2404 stays securely in place relative to the lens carriage.

[0039] Figure 28 shows a laminated crimped connection portion of an SMA actuator according to one embodiment. The laminated crimped connection portion 2412 is configured to attach the SMA wire 2408 to the bending actuator and to create an electrical circuit connection with the SMA wire 2408. In various embodiments, the laminated crimped connection portion 2412 includes a laminate formed of one or more layers of insulators and one or more layers of conductive layers formed in the crimped portion.

[0040] For example, a polyimide layer is placed on at least a portion of the stainless steel portion forming the crimped section 2413. Next, a conductive layer, such as copper, is placed on the polyimide layer, which is electrically connected to one or more signal traces 2415 located on the distortion actuator. The SMA wire is also brought into electrical contact with the conductive layer by deforming the crimped section to contact the SMA wire. Thus, the conductive layer connected to one or more signal traces is used to apply a power signal to the SMA wire using techniques including those described herein. In some embodiments, a second polyimide layer is formed across the conductive layer in areas where the conductive layer does not contact the SMA wire. In some embodiments, a laminated crimped connection 2412 is formed on the crimped section 2413 using deposition and etching techniques, including those known in the art. In other embodiments, the laminated crimped connection 2412 and one or more electrical traces are formed separately from the crimped section 2413 and the distortion actuator and attached to the crimped section 2412 and the distortion actuator using techniques including welding, adhesives, and other techniques known in the art.

[0041] Figure 29 shows an SMA actuator including a distortion actuator with a laminated hammock. As shown in Figure 29, when a power signal is applied, the SMA wire contracts or shortens, moving the distortion arm and laminated hammock in the positive z direction. Similarly, a laminated hammock in contact with an object moves that object, such as a lens carriage, in the positive z direction. When the power signal is reduced or removed, the SMA wire lengthens, moving the distortion arm and laminated hammock in the negative z direction.

[0042] Figure 30 shows an exploded view of an SMA system including an SMA actuator with a distortion actuator according to one embodiment. As described herein, in some embodiments, the SMA system is configured to be used in conjunction with one or more camera lens elements as an autofocus drive. As shown in Figure 30, the SMA system includes a return spring 3003, which, according to various embodiments, is configured to move the lens carriage 3005 in the opposite direction to the z-stroke when the SMA wire is deactivated and the tension of the SMA wire 3008 is reduced. In some embodiments, the SMA system includes a reinforcing member 3000 positioned on the return spring 3003. In some embodiments, the SMA system includes a housing 3009 formed of two parts configured to receive the return spring 3003 and act as a sliding bearing to guide the lens carriage in the z-stroke direction. The housing 3009 is also configured to be positioned on the distortion actuator 3002. The distortion actuator 3002 includes a slide base 3001 formed of two parts, similar to those described herein. The slide base 3001 is divided, with two sides electrically isolated (for example, one side being ground and the other side being power), so that, according to some embodiments, current flows through multiple parts of the slide base 3001 to the wire.

[0043] The distortion actuator 3002 includes a distortion arm 3004. Each pair of distortion actuators 3002 is formed on a separate part of the distortion actuator 3002. The distortion actuator 3002 also includes an SMA wire mounting structure, such as a resistance welding wire crimping section 3012. The SMA system optionally includes a flexible circuit 3020 for electrically connecting an SMA wire 3008 to one or more control circuits.

[0044] As shown in Figure 30, the slide base 3001 is positioned on an optional adapter plate 3014. The adapter plate is configured so that the SMA system or the distortion actuator 3002 can mate with another system, such as an OIS, an additional SMA system, or other components. Figure 31 shows an SMA system 3101 including an SMA actuator with a distortion actuator 3002 according to one embodiment.

[0045] Figure 32 shows an SMA actuator including a distortion actuator according to one embodiment. The distortion actuator 3002 includes a distortion arm 3004. As described herein, the distortion arm 3004 is configured to move along the z-axis when the SMA wire 3012 is activated or deactivated. The SMA wire 2408 is attached to the resistance welding wire crimp section 3012. According to the embodiment shown in Figure 32, the distortion arm 3004 is configured to mate with an object such as a lens carriage without using a center section, using a two-yoke capture joint.

[0046] Figure 33 shows a two-yoke capture joint of a pair of bending arms of an SMA actuator according to one embodiment. Figure 33 also shows a plated pad used to attach an optional flex circuit to the slide base. In some embodiments, the plated pad is formed using gold. Figure 34 shows a resistance weld crimp for an SMA actuator according to one embodiment, used to attach an SMA wire to the bending actuator. In some embodiments, glue or adhesive may also be placed on top of the weld as fatigue strain relief during operation and impact loads to support mechanical strength and work.

[0047] Figure 35 shows an SMA actuator including a distortion actuator with two yoke capture joints. As shown in Figure 35, when a power signal is applied, the SMA wires contract or shorten, moving the distortion arm in the positive z direction. The two yoke capture joints contact an object, and then move that object, for example, a lens carriage, in the positive z direction. When the power signal is reduced or removed, the SMA wires lengthen, moving the distortion arm in the negative z direction. The yoke capture features ensure that the distortion arm remains in the correct position relative to the lens carriage.

[0048] Figure 36 shows an SMA bimorph liquid lens according to one embodiment. The SMA bimorph liquid lens 3501 includes a liquid lens subassembly 3502, a housing 3504, and a circuit comprising an SMA actuator 3506. In various embodiments, the SMA actuator includes four bimorph actuators 3508, for example, in the embodiments described herein. The bimorph actuators 3508 are configured to press a molding ring 3510 located on a flexible film 3512. The rings warp the film 3512 / liquid 3514, thereby altering the optical path through the film 3512 / liquid 3514. A liquid-containing ring 3516 is used to contain the liquid 3514 between the film 3512 and the lens 3518. Equal forces from the bimorph actuators alter the focus of the image in the Z direction (perpendicular to the lens), thereby enabling autofocus functionality. The differential force from the bimorph actuator 3508 can move the light ray in the X and Y axes, thereby enabling it to function as an optical image stabilizer according to some embodiments. Both OIS and AF functions can be achieved simultaneously by appropriately controlling each actuator. In some embodiments, three actuators are used. A circuit with an SMA actuator 3506 has one or more contacts 3520 for control signals to actuate the SMA actuator. According to some embodiments including four SMA actuators, the circuit with the SMA actuator 3506 includes four power circuit control contacts for each SMA actuator and a common return contact.

[0049] Figure 37 shows an oblique view of an SMA bimorph liquid lens according to one embodiment. Figure 38 shows a cross-sectional view of the bottom surface of an SMA bimorph liquid lens according to one embodiment. Figure 39 shows an SMA system including an SMA actuator 3902 with bimorph actuators according to one embodiment. The SMA actuator 3902 includes four bimorph actuators using the techniques described herein. As shown in Figure 40, two of the bimorph actuators are configured as positive z-stroke actuators 3904 and two are configured as negative z-stroke actuators 3906, which illustrates the SMA actuator 3902 with bimorph actuators according to one embodiment. The actuators 3906 and 3904 located on opposite sides are configured to control movement in both directions over the entire stroke range. This provides the ability to adjust the control code to compensate for tilt. In various embodiments, two SMA wires 3908 mounted on the top of the component allow for positive z-stroke displacement. Two SMA wires mounted on the bottom of the component allow for negative z-stroke displacement. In some embodiments, each bimorph actuator is mounted on an object, such as a lens carriage 3910, using tabs to engage with the object. The SMA system includes an upper spring 3912 configured to provide stability to the lens carriage 3910 in an axis perpendicular to the z-stroke axis, for example, in the x-axis and y-axis directions. Furthermore, an upper spacer 3914 is configured to be positioned between the upper spring 3912 and the SMA actuator 3902. A bottom spacer 3916 is configured to be positioned between the SMA actuator 3902 and the bottom spring 3918. The bottom spring 3918 is configured to provide stability to the lens carriage 3910 in an axis perpendicular to the z-stroke axis, for example, in the x-axis and y-axis directions. The bottom spring 3918 is configured to be positioned on a base 3920, such as those described herein.

[0050] Figure 41 shows the length 4102 of the bimorph actuator 4103 and the location of the bonding pad 4104, so that the SMA wire 4206 extends beyond the bimorph actuator. A wire longer than the bimorph actuator is used to increase the stroke and force. Therefore, the length 4108 of the extension of the SMA wire 4206 beyond the bimorph actuator 4103 is used to set the stroke and force for the bimorph actuator 4103.

[0051] Figure 42 shows an exploded view of an SMA system including an SMA bimorph actuator 4202 according to one embodiment. According to various embodiments, the SMA system is configured to generate one or more electrical circuits for independently powering the SMA wires using separate metallic materials and non-conductive adhesives. Some embodiments include four bimorph actuators, such as those described herein, where the AF size has no impact. Two of the bimorph actuators are configured as positive z-stroke actuators and two as negative z-stroke actuators. Figure 43 shows an exploded view of a subsection of an SMA actuator according to one embodiment. The subsection includes a negative actuator signal connector 4302 and a base 4304 housing a bimorph actuator 4306. The negative actuator signal connector 4302 includes a wire bonding pad 4308 for connecting the SMA wires of the bimorph actuator 4306 using techniques including those described herein. The negative actuator signal connector 4302 is attached to the base 4304 using an adhesive layer 4310. The subdivision also includes a positive actuator signal connector 4314 with a wire bonding pad 4316 for connecting the SMA wires 4312 of the bimorph actuator 4306 using techniques including those described herein. The positive actuator signal connector 4314 is attached to the base 4304 using an adhesive layer 4318. Each of the base 4304, the negative actuator signal connector 4302, and the positive actuator signal connector 4314 is formed of a metal, such as stainless steel. Connection pads 4322 on each of the base 4304, the negative actuator signal connector 4302, and the positive actuator signal connector 4314 are configured to electrically connect the control signal and ground in order to actuate the bimorph actuator 4306 using techniques including those described herein. In some embodiments, the connection pads 4322 are gold-plated. Figure 44 shows a subdivision of the SMA actuator according to one embodiment. In some embodiments, the gold-plated pads are formed in the stainless steel layer for solder bonding or other known electrical termination methods.Furthermore, the formed wire bonding pads are used for signal joints to electrically connect SMA wires for power signals.

[0052] Figure 45 shows a 5-axis sensor shift system according to one embodiment. The 5-axis sensor shift system is configured to move an object, such as an image sensor, in five axes relative to one or more lenses. This includes translation and pitch / roll tilt along the X / Y / Z axes. Optionally, the system is configured to use only four axes, with translation and pitch / roll tilt along the X / Y axes, together with a separate AF located on top, to perform Z movement. Other embodiments include a 5-axis sensor shift system configured to move one or more lenses relative to an image sensor. In some embodiments, a static lens stack is mounted on the top cover and inserted into the ID (without touching the orange movable carriage located inside).

[0053] Figure 46 shows an exploded view of a 5-axis sensor shift system according to one embodiment. The 5-axis sensor shift system includes two circuit components, namely a flexible sensor circuit 4602 and a bimorph actuator circuit 4604, and 8 to 12 bimorph actuators 4606 built on the bimorph circuit component using techniques including those described herein. The 5-axis sensor shift system includes a movable carriage 4608 configured to hold one or more lenses and an outer housing 4610. The bimorph actuator circuit 4604, according to one embodiment, includes 8 to 12 SMA actuators, such as those described herein. The SMA actuators are configured to move the movable carriage 4608 in five axes, e.g., x, y, z, pitch, and roll, as in other 5-axis systems described herein.

[0054] Figure 47 shows an SMA actuator according to one embodiment, which includes a bimorph actuator incorporated into the circuit for all motions. Embodiments of the SMA actuator may include 8 to 12 bimorph actuators 4606. However, other embodiments may include more or fewer. Figure 48 shows an SMA actuator 4802 according to one embodiment, which includes a bimorph actuator incorporated into the circuit for all motions, partially formed to fit within a corresponding outer housing 4804. Figure 49 shows a cross-section of a 5-axis sensor shift system according to one embodiment.

[0055] Figure 50 shows an SMA actuator 5002 according to one embodiment, which includes a bimorph actuator. The SMA actuator 5002 is configured to use four side-mounted SMA bimorph actuators 5004 to move an image sensor, lens, or various other payloads in the x and y directions. Figure 51 shows a top view of the SMA actuator including the bimorph actuators with an image sensor, lens, or various other payloads moved to different x and y positions.

[0056] Figure 52 shows an SMA actuator including a bimorph actuator 5202 according to one embodiment, configured as a box bimorph autofocus. Four top and bottom mounted SMA bimorph actuators, such as those described herein, are configured to move together to produce movement in the z-stroke direction for autofocus motion. Figure 53 shows an SMA actuator including a bimorph actuator according to one embodiment, in which two top mounted bimorph actuators 5302 are configured to push down one or more lenses. Figure 54 shows an SMA actuator including a bimorph actuator according to one embodiment, in which two bottom mounted bimorph actuators 5402 are configured to push up one or more lenses. Figure 55 shows an SMA actuator including a bimorph actuator according to one embodiment, showing that four top and bottom mounted SMA bimorph actuators 5502, such as those described herein, are used to move one or more lenses to produce tilt motion.

[0057] Figure 56 shows an SMA system including an SMA actuator according to one embodiment, which includes a bimorph actuator configured as a two-axis lens-shift OIS. In some embodiments, the two-axis lens-shift OIS is configured to move the lens along the X / Y axes. In some embodiments, the movement along the Z axis is produced by a separate AF, such as those described herein. Four bimorph actuators push the sides of the autofocus for the movement of the OIS. Figure 57 shows an exploded view of an SMA system including an SMA actuator 5802 according to one embodiment, which includes a bimorph actuator 5806 configured as a two-axis lens-shift OIS. Figure 58 shows a cross-section of an SMA system including an SMA actuator 5802 according to one embodiment, which includes a bimorph actuator 5806 configured as a two-axis lens-shift OIS. Figure 59 shows a box bimorph actuator 5802 according to one embodiment for use in an SMA system configured as a two-axis lens-shift OIS, such as being manufactured before being molded to fit into a system. Such a system may be configured to have a high OIS stroke (e.g., ±200 μm or more). Furthermore, such embodiments are configured to have a wide range of motion and good dynamic tilt of OIS using four sliding bearings, for example, POM sliding bearings. The embodiments are configured to integrate easily with AF designs (e.g., VCM or SMA).

[0058] Figure 60 shows an SMA system including an SMA actuator according to one embodiment, which includes a bimorph actuator configured as a 5-axis lens-shift OIS and autofocus. In some embodiments, the 5-axis lens-shift OIS and autofocus are configured to move the lens along the X / Y / Z axes. In some embodiments, the pitch and yaw axis movements are to enable dynamic tilt adjustment. Eight bimorph actuators are used to bring about the autofocus and OIS movements using the techniques described herein. Figure 61 shows an exploded view of an SMA system including an SMA actuator 6202 according to one embodiment, which includes a bimorph actuator 6204 according to one embodiment, configured as a 5-axis lens-shift OIS and autofocus. Figure 62 shows a cross-section of an SMA system including an SMA actuator 6202 according to one embodiment, which includes a bimorph actuator 6204 configured as a 5-axis lens-shift OIS and autofocus. Figure 63 shows a box-bimorph actuator 6202 according to one embodiment for use in an SMA system configured as a 5-axis lens-shift OIS and autofocus, such that it is manufactured before being molded to fit within the system. Such a system may be configured to have a high OIS stroke (e.g., ±200 μm or more) and a high autofocus stroke (e.g., 400 μm or more). Furthermore, such embodiments can be adjusted to eliminate any tilt and eliminate the need for a separate autofocus assembly.

[0059] Figure 64 shows an SMA system including an SMA actuator according to one embodiment, which includes a bimorph actuator configured as an outward-pushing box. In some embodiments, the bimorph actuator assembly is configured to enclose an object such as a lens carriage. The circuit assembly is for moving the flexible part for low X / Y / Z stiffness together with the lens carriage. The rear end pad of the circuit is static. The outward-pushing box can be configured for either four bimorph actuators or eight bimorph actuators. Thus, the outward-pushing box can be configured as a four-bimorph actuator on the sides of an OIS moving along the X and Y axes. The outward-pushing box can be configured as a four-bimorph actuator at the top and bottom for autofocus moving along the z axis. The outward-pushing box can be configured as an eight-bimorph actuator at the top, bottom, and multiple sides for OIS and autofocus with movement along the x, y, and z axes, and allow for three-axis tilt (pitch / roll / yaw). Figure 65 shows an exploded view of an SMA system including an SMA actuator 6602 according to one embodiment, which includes a bimorph actuator 6604 configured as an outward-pushing box. Thus, the SMA actuator is configured such that the bimorph actuator acts on the outer housing 6504 to move the lens carriage 6506 using the techniques described herein. Figure 66 shows an SMA system including an SMA actuator 6602 according to one embodiment, which includes a bimorph actuator configured as an outward-pushing box, partially molded to receive the lens carriage 6604. Figure 67 shows an SMA system including an SMA actuator 6602 with a bimorph actuator 6604 according to one embodiment, which is manufactured as an outward-pushing box, as if it were being molded to fit within the system.

[0060] Figure 68 shows an SMA system including an SMA actuator 6802 according to one embodiment, which includes a bimorph actuator configured as a 3-axis sensor-shift OIS. In some embodiments, the Z-axis motion comes from a separate autofocus system. Four bimorph actuators are configured to push multiple sides of the sensor carriage 6804 to bring motion to the OIS using the techniques described herein. Figure 69 shows an exploded view of an SMA including an SMA actuator 6802 according to one embodiment, which includes a bimorph actuator configured as a 3-axis sensor-shift OIS. Figure 70 shows a cross-section of an SMA system including an SMA actuator 6802 according to one embodiment, which includes a bimorph actuator 6806 configured as a 3-axis sensor-shift OIS. Figure 71 shows components of a box bimorph actuator 6802 according to one embodiment for use in an SMA system configured as a 3-axis sensor-shift OIS, such as being manufactured before being molded to fit within the system. Figure 72 shows a flexible sensor circuit for use in an SMA system according to one embodiment, configured as a 3-axis sensor-shift OIS. Such a system may be configured to have a high OIS stroke (e.g., ±200 μm or more) and a high autofocus stroke (e.g., 400 μm or more). Furthermore, such an embodiment may be configured to have a wide range of two-axis motion and good dynamic tilt of OIS using four sliding bearings, e.g., POM sliding bearings. The embodiment may be configured to be easily integrated with AF designs (e.g., VCM or SMA).

[0061] Figure 73 shows an SMA system including an SMA actuator 7302 according to one embodiment, which includes a bimorph actuator 7304 configured as a 6-axis sensor-shift OIS and autofocus. In some embodiments, the 6-axis sensor-shift OIS and autofocus are configured to move the lens on the X / Y / Z / pitch / yaw / roll axes. In some embodiments, the movement on the pitch and yaw axes is to enable dynamic tilt adjustment. Eight bimorph actuators are used to bring about the autofocus and OIS movement using the techniques described herein. Figure 74 shows an exploded view of an SMA system including an SMA actuator 7402 according to one embodiment, which includes a bimorph actuator 7404 configured as a 6-axis sensor-shift OIS and autofocus. Figure 75 shows a cross-section of an SMA system including an SMA actuator 7402 according to one embodiment, which includes a bimorph actuator configured as a 6-axis sensor-shift OIS and autofocus. Figure 76 shows a box-bimorph actuator 7402 according to one embodiment for use in an SMA system configured as a 6-axis sensor-shift OIS and autofocus, such that it is manufactured before being molded to fit within the system. Figure 77 shows a flexible sensor circuit according to one embodiment for use in an SMA system configured as a 3-axis sensor-shift OIS. Such a system may be configured to have a high OIS stroke (e.g., ±200 μm or more) and a high autofocus stroke (e.g., 400 μm or more). Furthermore, such an embodiment allows for adjustment of any tilt and eliminates the need for a separate autofocus assembly.

[0062] Figure 78 shows an SMA system including an SMA actuator according to one embodiment, which includes a bimorph actuator configured as a two-axis camera tilt OIS. In some embodiments, the two-axis camera tilt OIS is configured to move the camera along the pitch / yaw axis. Four bimorph actuators are used to push the top and bottom of the autofocus for the movement of the entire camera for the pitch and yaw movements of the OIS using the techniques described herein. Figure 79 shows an exploded view of an SMA system including an SMA actuator 7902 according to one embodiment, which includes a bimorph actuator 7904 configured as a two-axis camera tilt OIS. Figure 80 shows a cross-section of an SMA system including an SMA actuator according to one embodiment, which includes a bimorph actuator configured as a two-axis camera tilt OIS. Figure 81 shows a box bimorph actuator according to one embodiment for use in an SMA system configured as a two-axis camera tilt OIS, such as being manufactured before being molded to fit within the system. Figure 82 shows a flexible sensor circuit for use in an SMA system according to one embodiment, configured as a two-axis camera tilt OIS. Such a system may be configured to have a high OIS stroke (e.g., ±3 degrees or more). Embodiments are configured to be easily integrated with autofocus (AF) designs (e.g., VCM or SMA).

[0063] Figure 83 shows an SMA system including an SMA actuator according to one embodiment, which includes a bimorph actuator configured as a 3-axis camera tilt OIS. In some embodiments, a 2-axis camera tilt OIS is configured to move the camera along the pitch / yaw / roll axes. Four bimorph actuators are used to push the top and bottom of the autofocus for the overall camera movement for the pitch and yaw movements of the OIS using the techniques described herein, and four bimorph actuators are used to push multiple sides of the autofocus for the overall camera movement for the roll movements of the OIS using the techniques described herein. Figure 84 shows an exploded view of an SMA system including an SMA actuator 8402 according to one embodiment, which includes a bimorph actuator 8404 configured as a 3-axis camera tilt OIS. Figure 85 shows a cross-section of an SMA system including an SMA actuator according to one embodiment, which includes a bimorph actuator configured as a 3-axis camera tilt OIS. Figure 86 shows a box bimorph actuator for use in an SMA system according to one embodiment, which is configured as a 3-axis camera tilt OIS, such that it is manufactured before being molded to fit within the system. Figure 87 shows a flexible sensor circuit for use in an SMA system according to one embodiment, configured as a 3-axis camera tilt OIS. Such a system may be configured to have a high OIS stroke (e.g., ±3 degrees or more). The embodiment is configured to easily integrate with AF designs (e.g., VCM or SMA).

[0064] Figure 88 shows exemplary dimensions for a bimorph actuator of an SMA actuator according to several embodiments. While these dimensions represent a preferred embodiment, those skilled in the art will understand that other dimensions may be used depending on the desired characteristics of the SMA actuator.

[0065] Figure 89 shows a lens system for a folded camera according to one embodiment. The folded camera includes a folding lens 8902 configured to bend light into a lens system 8901 which includes one or more lenses 8903a to d. In some embodiments, the folding lens is one or more of either a prism or a lens. The lens system 8901 is configured to have a principal axis 8904 that makes an angle with a transmission axis 8906 parallel to the direction in which the light travels before reaching the folding lens 8902. For example, a folded camera is used in a camera-equipped mobile phone system to reduce the height of the lens system 8901 in the direction of the transmission axis 8906.

[0066] Embodiments of a lens system include one or more liquid lenses, such as those described herein. The embodiment shown in Figure 89 includes two liquid lenses 8903b, 8903d, such as those described herein. One or more liquid lenses 8903b, 8903d are configured to be actuated using techniques including those described herein. The liquid lenses are actuated using actuators, including, but not limited to, distortion actuators, bimorph actuators, and other SMA actuators. Figure 108 includes a liquid lens actuated using a distortion actuator 60 according to one embodiment. The liquid lens includes a molding ring coupler 64, a liquid lens assembly 61, one or more distortion actuators 60, such as those described herein, a slide base 65, and a base 62. One or more distortion actuators 60 are configured to move the molding ring / coupler 64 to move or shape a ray by changing the shape of the flexible membrane of the liquid lens assembly 61, as described herein, for example. In some embodiments, three or four actuators are used. The liquid lens may be configured, either alone or in combination with other lenses, to function as an autofocus or optical image stabilization mechanism. The liquid lens may also be configured to orient an image onto an image sensor in other ways.

[0067] Figure 90 shows several embodiments of a lens system 9001, including liquid lenses 9002a to 9002h, for forming an image on an image sensor 9004. As shown in the figure, the liquid lenses 9002a to 9002h may include any lens shape and may be configured to be dynamically configured to adjust the optical path through the lens using techniques including those described herein.

[0068] The lens system for the folding camera is configured to include an actuated bent lens 9100. An example of an actuated bent lens is a prism tilt, such as the one shown in Figure 91. In the example shown in Figure 91, the bent lens is a prism 9102 located in actuator 9104. The actuator includes, but is not limited to, an SMA actuator, such as those described herein. In some embodiments, the prism tilt is located in an SMA actuator including four bimorph actuators 9106, such as those described herein. According to some embodiments, the actuated bent lens 9100 is configured as an optical image stabilization mechanism using techniques including those described herein. For example, the actuated bent lens is configured to include an SMA system, such as the one shown in Figure 39. Another example of an actuated bent lens may include an SMA actuator, such as the one shown in Figure 21. However, the bent lens may also include other actuators.

[0069] Figure 92 shows an offset bimorph arm according to one embodiment. The bimorph arm 9201 includes a bimorph beam 9202 having a pre-formed offset 9203. The pre-formed offset 9203 enhances the mechanical benefit of generating a higher force than a bimorph arm without an offset. According to some embodiments, the depth 9204 (also referred herein as the bend surface z-offset 9204) and the length 9206 (also referred herein as the trough width 9206) of the offset are configured to define the characteristics of the bimorph arm, such as the peak force. For example, the graph in Figure 106 shows the relationship between the bend surface z-offset 9204, the trough width 9206, and the peak force of a bimorph beam 9202 according to one embodiment.

[0070] A bimorph arm comprises one or more SMA materials, such as SMA ribbons or SMA wires 9210, as described herein. The SMA materials are attached to the beam using techniques including those described herein. In some embodiments, the SMA material, such as the SMA wire 9210, is attached to the fixed end 9212 and the load-point end 9214 of the bimorph arm, so that a pre-formed offset 9203 is located between the two ends to which the SMA material is attached. In various embodiments, multiple ends of the SMA material are electrically and mechanically connected to contacts configured to supply current to the SMA material using techniques including those known in the art. Bimorph arms with offsets may be included in SMA actuators and systems, such as those described herein.

[0071] Figure 93 shows a bimorph arm with an offset and limiter according to one embodiment. The bimorph arm 9301 includes a bimorph beam 9302 having a preformed offset 9303 and a limiter 9304 adjacent to the preformed offset 9303. The offset 9303 enhances the mechanical benefit of generating a higher force than a bimorph arm 9301 without an offset, and the limiter 9304 prevents the arm from moving in a direction away from the unfixed load point end 9306 of the bimorph actuator. The bimorph arm 9301 with the preformed offset 9303 and limiter 9304 may be included in SMA actuators and systems such as those described herein. The bimorph arm 9301 includes an SMA ribbon or SMA wire 9308 attached to the bimorph arm 9301 using one or more SMA materials, such as those described herein, including techniques described herein.

[0072] Figure 94 shows a bimorph arm with an offset and limiter according to one embodiment. The bimorph arm 9401 includes a bimorph beam 9402 having a preformed offset 9403 and a limiter 9404 adjacent to the preformed offset 9403. The limiter 9404 is formed as part of a base 9406 for the bimorph arm 9401. The base 9406 includes a recess 9408 configured to receive the bimorph arm 9401 and the offset portion of the bimorph beam. The bottom of the recess configured as the limiter 9404 is adjacent to the preformed offset 9403. The base 9406 may also include one or more portions 9410 configured to support multiple portions of the bimorph arm when not in operation. The bimorph arm 9401 with the preformed offset 9403 and limiter 9404 may be included in SMA actuators and systems such as those described herein. The bimorph arm 9401 includes an SMA ribbon or SMA wire, such as those described herein, attached to the bimorph arm 9401 using a technique including one or more SMA materials, such as those described herein.

[0073] Figure 95 shows a base embodiment including an offset bimorph arm according to one embodiment. The bimorph arm 9501 includes a bimorph beam 9502 having a pre-formed offset 9504. The bimorph arm may also include a limiter using techniques including those described herein. The bimorph arm 9501 includes one or more SMA materials, such as an SMA ribbon or SMA wire 9506, attached to the bimorph arm 9501 using techniques including those described herein.

[0074] Figure 96 shows an embodiment of a base 9608 including two offset bimorph arms according to one embodiment. Each bimorph arm 9601a, 9601b includes a bimorph beam 9602a, 9602b having a pre-formed offset 9604a, 9604b. Each bimorph arm 9601a, 9601b includes an SMA ribbon or SMA wire 9606a, 9606b, such as those described herein, attached to the bimorph arm 9501 using one or more SMA materials, for example, techniques including those described herein. Each bimorph arm 9601a, 9601b may also include a limiter using techniques including those described herein. Some embodiments include a base including three or more bimorph arms formed using techniques including those described herein. According to some embodiments, the bimorph arm 9601 is formed integrally with the base 9608. In other embodiments, one or more of the bimorph arms 9602a, 9602b are formed separately from the base 9608 and are attached to the base 9608 using techniques including, but not limited to, soldering, resistance welding, laser welding, and adhesives. In some embodiments, two or more bimorph arms 9601a, 9601b are configured to act on a single object. This allows for the ability to increase the force applied to the object. The graph in Figure 107 below illustrates an example of how the box volume, which is an approximation of the box containing the entire bimorph actuator, relates to the amount of work per bimorph component. The box volume is estimated using the length 9612 of the bimorph actuator, the width 9610 of the bimorph actuator, and the height 9614 of the bimorph actuator (collectively referred to as the “box volume”).

[0075] Figure 97 shows a curved arm including load point extensions according to one embodiment. The curved arm 9701 includes a beam section 9702 and one or more load point extensions 9704a, 9704b extending from the beam section 9702. Each end 9706a, 9706b of the curved arm 9701 is configured to be attached to or integrally formed with 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 section 9702, offset from the load points 9710a, 9710b of the beam section 9702. The load points 9710a, 9710b are portions of the beam section 9702 configured to transmit the force of the curved arm 9701 to another object. In some embodiments, the load points 9710a, 9710b are the centers of the beam section 9702. In other embodiments, the load points 9710a and 9710b are located at positions other than the center of the beam section 9702. The load point extensions 9704a and 9704b are configured to extend in the direction of the longitudinal axis of the beam section 9702, toward the load points 9710a and 9710b of the beam section 9702, from the point where they are joined to the beam section 9702. In some embodiments, the ends of the load point extensions 9704a and 9704b extend to at least the load points 9710a and 9710b of the beam section 9702. The bending arm 9701 includes one or more SMA materials, such as SMA ribbons or SMA wires 9712, as described herein. The SMA materials, such as SMA wires 9712, are attached to both ends located opposite the beam section 9702. The SMA materials are attached to both ends located opposite the beam section using techniques including those described herein. In some embodiments, the lengths of the load point extensions 9704a and 9704b may be configured to be any length that falls within the longitudinal length of the associated flat (non-operated) beam portion 9702 of the bending arm 9701.

[0076] Figure 98 shows a deformable arm 9801 in the operating position, including a load point extension 9810 according to one embodiment. SMA material attached to both ends opposite the beam section 9802 is actuated using techniques including those described herein. The load point 9804 allows the deformable arm 9801 to have a greater stroke range than a deformable arm without the extension. Therefore, a deformable arm with a load point extension can have a greater maximum vertical stroke. A deformable arm with a load point extension may be included in SMA actuators and systems, such as those described herein.

[0077] Figure 99 shows a bimorph arm including load point extensions according to one embodiment. The bimorph arm 9901 includes a beam section 9902 and one or more load point extensions 9904a, 9904b extending from the beam section. One end of the bimorph arm 9901 is configured to be attached to or integrally formed with a plate or other base using techniques including those described herein. The end of the beam section 9902 opposite to the attached or integrally formed end is not fixed and can move freely. According to some embodiments, one or more load point extensions 9904a, 9904b are attached to or integrally formed with the beam section 9902 offset from the free end of the beam section 9902. The load point extensions 9904a, 9904b are configured to extend away from the plane containing the longitudinal axis of the beam section 9902 from the point where they are joined to the beam section 9902. For example, one or more load point extensions 9904a, 9904b extend in the direction in which the free end of the beam section extends during operation. Some embodiments of the bimorph arm 9901 include one or more load point extensions 9904a, 9904b having a longitudinal axis that forms a certain angle, for example, 1 to 90 degrees, with a plane containing the longitudinal axis of the beam section. In some embodiments, the ends 9910a, 9910b of the load point extensions 9904a, 9904b are configured to engage with an object configured to be moved.

[0078] The bimorph arm 9901 includes one or more SMA materials, such as SMA ribbons or SMA wires 9906, as described herein. The SMA materials, such as SMA wires 9906, are attached to both ends located opposite the beam section 9902. The SMA materials are attached to both ends located opposite the beam section 9902 using techniques including those described herein. In some embodiments, the lengths of the load point extensions 9904a, 9904b may be configured to be any length. According to some embodiments, the location of the engagement points of an object by the ends 9910a, 9910b of the load point extensions 9904a, 9904b may be configured to be at any point along the longitudinal length of the beam section 9902. The height of the ends of the load point extensions above the beam section when the beam section is flat (unacted) may be configured to be any height. In some embodiments, the load point extension may be configured to be at least above the other portion of the bimorph arm when the bimorph arm is actuated.

[0079] Figure 100 shows a bimorph arm with a load point extension according to one embodiment in the operating position. The SMA material attached to both ends located opposite the beam section 2 is actuated using techniques including those described herein. The load point extension 10 allows the bimorph arm 1 to exert a greater stroke force than a bimorph arm without the extension. Therefore, the bimorph arm 1 with the load point extension 10 allows a greater force to be applied by the bimorph arm 1. The bimorph arm 1 with the load point extension 10 may be included in SMA actuators and systems such as those described herein.

[0080] Figure 101 shows an SMA optical image stabilization mechanism according to one embodiment. The SMA optical image stabilization mechanism 20 includes a movable plate 22 and a stationary plate 24. The movable plate 22 includes a spring arm 26 integrally formed with the movable plate 22. In some embodiments, the movable plate 22 and the stationary plate 24 are each formed to be unitary one-piece plates. The movable plate 22 includes a first SMA material mounting portion 28a and a second SMA material mounting portion 28b. The stationary plate 24 includes a first SMA material mounting portion 30a and a second SMA material mounting portion 30b. Each SMA material mounting portion 28, 30 is configured to fix SMA material, such as SMA wire, to the plate using resistance welding joints. The first SMA material mounting portion 28a of the movable plate 22 includes a first SMA wire 32a positioned between it and the first SMA material mounting portion 30a of the stationary plate, and a second SMA wire 32b positioned between it and the second SMA mounting portion 30b of the stationary plate 24. The second SMA material mounting portion 28b of the movable plate 22 includes a third SMA wire 32c positioned between it and the second SMA material mounting portion 30b of the stationary plate, and a fourth SMA wire 32d positioned between it and the first SMA mounting portion 30a of the stationary plate 24. The actuation of each SMA wire using techniques including those described herein moves the movable plate 22 away from the stationary plate 24. Figure 102 shows an SMA material mounting portion 40 of the movable part according to one embodiment. The SMA material mounting portion is configured to have SMA material, such as an SMA wire 41, resistance welded to the SMA material mounting portion 40. Figure 103 shows an SMA mounting portion 42 of a stationary plate to which a resistance-welded SMA wire 43 is attached, according to one embodiment.

[0081] Figure 104 shows an SMA actuator 45 including a distortion actuator according to one embodiment. The distortion actuator 46 includes a distortion arm 47, such as those described herein. The distortion arm 47 is configured to move along the z-axis when the SMA wire 48 is actuated or deacted, using techniques including those described herein. Each SMA wire 48 is attached to its respective resistance-welded wire crimp section 49 using resistance welding. Each resistance-welded wire crimp section 49 includes an island 50 isolated from the metal 51 forming the distortion arm 47 on at least one side of the SMA wire 48. The island structure may be used in other actuators, optical image stabilization mechanisms, and autofocus systems to connect at least one side of the SMA wire to an isolated island structure formed in a base metal layer, such as in the OIS application shown in Figure 101.

[0082] Figure 105 shows a resistance welding crimp section including an island for an SMA actuator according to one embodiment, used to attach an SMA wire 48 to a bending actuator 46 using techniques including those described herein. Figure 105a shows the bottom portion of the SMA actuator 45. According to some embodiments, the SMA actuator 45 is formed from a stainless steel base layer 51. A dielectric layer 52, such as a polyimide layer, is located in the bottom portion of the stainless steel base layer 51. According to some embodiments, a conductor layer 53 is electrically connected to the stainless steel island 50 by vias in the dielectric layer 52, allowing for electrical connection between a wire welded to the stainless steel island 50 and a conductor circuit attached to the stainless steel island. According to some embodiments, the island 50 is made by etching from the stainless steel base layer. The dielectric layer 52 maintains the position of the island 50 within the stainless steel base layer 51. The island 50 is configured to attach an SMA wire to it using techniques including those described herein, such as resistance welding. Figure 105b shows the top portion of the SMA actuator 45 including the island 50. In some embodiments, glue or adhesive may also be placed on top of the weld to support mechanical strength and work as a release of fatigue strain during operation and impact loads.

[0083] Figure 108 shows a lens system including an SMA actuator with a distortion actuator according to one embodiment. The lens system includes a liquid lens assembly 61 located on a base 62. The lens system also includes a molding ring / coupler 64 mechanically connected to the distortion actuator 60. The SMA actuator, including the distortion actuator 60 such as those described herein, is located on a slide base 65 located on the base 62. The SMA actuator is configured to move the molding ring / coupler 64 along the optical axis of the liquid lens assembly 61 by acting the distortion actuator 60 using techniques including those described herein. This moves the molding ring / coupler 64 to change the focus of the liquid lens within the liquid lens assembly.

[0084] Figure 109 shows an unfixed load-point end of a bimorph arm according to one embodiment. The unfixed load-point end 70 of the bimorph arm includes a flat surface 71 for attaching SMA material, such as an SMA wire 72. The SMA wire 72 is attached to the flat surface 71 by resistance welding 73. The resistance welding 73 is formed using techniques including those known in the art.

[0085] Figure 110 shows an unfixed load-point end of a bimorph arm according to one embodiment. The unfixed load-point end 76 of the bimorph arm includes a flat surface 77 for mounting SMA material, such as an SMA wire 78. The SMA wire 78 is attached to the flat surface 77 by resistance welding similar to that shown in Figure 109. Adhesive 79 is placed in the resistance weld. This allows for a more reliable bond 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 the art.

[0086] Figure 111 shows an unfixed load-point end of a bimorph arm according to one embodiment. The unfixed load-point end 80 of the bimorph arm includes a flat surface 81 for mounting SMA material, such as an SMA wire 82. A metal interlayer 84 is placed 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 placed on the flat surface 81 by resistance welding 83. The resistance welding 83 is formed using techniques including those known in the art. The metal interlayer 84 allows for better adhesion with the unfixed load-point end 80.

[0087] Figure 112 shows an unfixed load-point end of a bimorph arm according to one embodiment. The unfixed load-point end 88 of the bimorph arm includes a flat surface 89 for mounting SMA material, such as an SMA wire 90. A metal interlayer 92 is placed 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 resistance welding, similar to that shown in Figure 111. An adhesive 91 is placed on the resistance weld. This allows for a more reliable bond between the SMA wire 90 and the unfixed load-point end 88. The adhesive 91 includes, but is not limited to, conductive adhesives, non-conductive adhesives, and other adhesives known in the art.

[0088] Figure 113 shows a fixed end of a bimorph arm according to one embodiment. The fixed end 95 of the bimorph arm includes a flat surface 96 for attaching SMA material, such as an SMA wire 97. The SMA wire 97 is attached to the flat surface 96 by resistance welding 98. The resistance welding 98 is formed using techniques including those known in the art.

[0089] Figure 114 shows a fixed end of a bimorph arm according to one embodiment. The fixed end 120 of the bimorph arm includes a flat surface 121 for attaching SMA material, such as an SMA wire 122. The SMA wire 122 is attached to the flat surface 121 by resistance welding, similar to that shown in Figure 113. Adhesive 123 is placed over the resistance weld. This allows for a more reliable bond 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.

[0090] Figure 115 shows a fixed end of a bimorph arm according to one embodiment. The fixed end 126 of the bimorph arm includes a flat surface 127 for mounting SMA material, such as an SMA wire 128. A metal interlayer 130 is positioned 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 positioned on the flat surface 127 by resistance welding 129. The resistance welding 129 is formed using techniques including those known in the art. The metal interlayer 130 allows for better adhesion with the fixed end 126.

[0091] Figure 116 shows a fixed end of a bimorph arm according to one embodiment. The fixed end 135 of the bimorph arm includes a flat surface 136 for attachment to an SMA material, such as an SMA wire 137. A metal interlayer 138 is placed on the flat surface 136. The metal interlayer 136 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 resistance welding, similar to that shown in Figure 115. An adhesive 139 is placed on the resistance weld. This allows for a more reliable bond 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.

[0092] Figure 117 shows a rear view of the fixed end of a bimorph arm according to one embodiment. The bimorph arm 143 is configured according to several embodiments described herein. The fixed end 143 of the bimorph arm includes an island 144 isolated from the outer portion 145 of the fixed end 143. This allows the island 144 to be electrically and / or thermally isolated from the outer portion 145. In some embodiments, SMA material attached to opposing sides of the fixed end 143 of the bimorph arm is electrically connected to SMA material, such as SMA wire, through vias. The island 144 is located on an insulator 146, such as those described herein. The island 144 may be formed using etching techniques, including those known in the art.

[0093] Figure 118 shows an unfixed load-point end 70 of a bimorph arm according to one embodiment. The unfixed load-point end 70 of the bimorph arm includes a flat surface 71 configured to include a radiating surface area 74 extending from a resistance welding area 73. The radiating surface area 74 includes a tip end 76 and a base end 75. The flat surface 71 is configured to have an SMA material, such as an SMA wire 72, fixed to the flat surface 71. According to some embodiments, the SMA wire 72 is fixed to the flat surface 71 by resistance welding in the resistance welding area 73. The resistance welding is formed using techniques including those known in the art. In other embodiments, the SMA wire 72 is fixed to the flat surface 71 using other mounting techniques, including those described herein.

[0094] The temperature drop of the unfixed load point end 70 depends on the phase transition temperature of the SMA wire 72. The radiating surface area 74 significantly increases the surface area of ​​the unfixed load point end 70.

[0095] The increased surface area improves the temperature drop at the unfixed load point end 70. The increased surface area allows for cooling to prevent phase transitions in the shape memory alloy during operation. Figure 119 shows an unfixed load-point end 170 of a bimorph arm according to one embodiment. The unfixed load-point end 170 of the bimorph arm includes a flat surface 171 configured to include a radiating surface area 174 extending from a resistance welding region 173.

[0096] The radiating surface area 174 includes a tip portion 176 and a base portion 175. The flat surface 171 is configured to have an SMA material, such as an SMA wire 172, fixed to the flat surface 171. According to some embodiments, the SMA wire 172 is fixed to the flat surface 171 by resistance welding to a resistance welding area 173. In other embodiments, the SMA wire 172 is fixed to the flat surface 171 using other mounting techniques, including those described herein.

[0097] Furthermore, the unfixed load point end 170 includes a proximal opening 178 and a tip opening 179 separated by a resistance welding region 173. The proximal opening 178 and the tip opening 179 are formed using techniques including those known in the art. Although the openings 178, 179 are shown as fully through-shaped, in some examples the openings 178, 179 may be partially etched.

[0098] The proximal end opening 178 and the tip end opening 179 physically interrupt the flat surface 171 and define the location of the resistance welding area 173. According to some embodiments, the openings 178 and 179 are configured to mitigate interference between the wire 172 and the flat surface 171 in the vicinity of the resistance welding area 173.

[0099] Figure 120 shows an unfixed load point end 270 of a bimorph arm according to one embodiment. The unfixed load point end 270 of the bimorph arm includes a flat surface 271 configured to include a radiating surface area 274 extending from a resistance welding area 273. The flat surface 271 is configured to have an SMA material, such as an SMA wire 272, fixed to the flat surface 271. According to some embodiments, the SMA wire 272 is fixed to the flat surface 271 by resistance welding to the resistance welding area 273. In other embodiments, the SMA wire 272 is fixed to the flat surface 271 using other mounting techniques, including those described herein.

[0100] Furthermore, the unfixed load point end 270 includes a proximal end opening 278 and a proximal end opening 279 separated by a resistance welding area 273. The unfixed load point end 270 also includes an elongated opening 280 corresponding to a portion of the SMA wire 272. The elongated opening 280 may be removed to form wire clearance for the SMA wire 272. In some embodiments, the elongated opening 280 extends from the proximal end opening 278. Although the openings 278, 279, 280 are shown as fully through-shaped, in some examples the openings 278, 279, 280 may be partially etched.

[0101] The proximal opening 278 and the tip opening 279 physically interrupt the flat surface 271 and define the location of the resistance welding area 273. Similarly, the elongated opening 280 physically interrupts the flat surface 271 and defines the location of the SMA wire 272. According to some embodiments, the openings 278, 279, and 280 are configured to mitigate interference between the wire 272 and the flat surface 271 in the vicinity of the resistance welding area 273.

[0102] Figure 121 shows an unfixed load point end 370 of a bimorph arm according to one embodiment. The flat surface 371 is configured to have an SMA material, such as an SMA wire 372, fixed to the flat surface 371. According to some embodiments, the SMA wire 372 is fixed to the flat surface 371 by resistance welding to a resistance welding area 373. The resistance welding area 373 is at least partially isolated by a nonlinear opening 378. In some configurations, the nonlinear opening 378 is U-shaped to physically isolate up to 90% of the resistance welding area 373. The resistance welding area 373 may be mounted on a weld tongue defined by the nonlinear opening 378. In other embodiments, the SMA wire 372 is fixed to the flat surface 371 using other mounting techniques, including those described herein. Although the nonlinear opening 378 is shown as a fully through shape, in some examples the nonlinear opening 378 may be partially etched.

[0103] The increased surface area from the radiating surface area 374 allows for cooling to prevent phase transitions in the shape memory alloy during operation. In some alternative embodiments, the resistance welding area 373 may be completely etched from the unfixed load point end 370. Alternatively, the resistance welding area 373 may include a partial etching slot to increase tongue compliance.

[0104] Figure 122 shows an unfixed load point end 470 of a bimorph arm according to one embodiment. An adjacent flat surface 471 is provided for fixing an SMA material, such as an SMA wire 472. The SMA wire 472 is fixed to the flat surface 471 by a resistance welding area 473, which is at least partially separated by a nonlinear opening 478.

[0105] The resistance welding area 473 may be mounted using a partially etched slot 479 within a nonlinear opening 478. In some configurations, the nonlinear opening 478 physically interrupts the flat surface 471 and defines the location of the resistance welding area 473. According to some embodiments, the openings 178,179 are configured to mitigate interference between the wire 172 and the flat surface 171 in the vicinity of the resistance welding area 173. Although the openings 178,179 are shown as fully through-shaped, in some examples the openings 178,179 may be partially etched.

[0106] The increased surface area from the radiating surface area 474 allows for cooling to prevent phase transitions in the shape memory alloy during operation. The disclosed embodiments may be applied to the fixed end of a bimorph arm. Figures 123 to 125 are provided herein as exemplary embodiments of a fixed end incorporating the disclosed embodiments.

[0107] Figure 123 shows a fixed end of a bimorph arm according to one embodiment. The fixed end 95 of the bimorph arm includes a flat surface 96 for attaching SMA material, such as an SMA wire 97. The SMA wire 97 is attached to the flat surface 96 by a resistance welding area 98. The resistance welding area 98 is formed using techniques including those known in the art.

[0108] The fixed end 95 includes a proximal end opening 93 and a tip end opening 94 separated by a resistance welding area 98. The proximal end opening 93 and the tip end opening 94 are formed using techniques including those known in the art.

[0109] The proximal end opening 93 and the tip end opening 94 physically interrupt the flat surface 96 and define the location of the resistance weld 98. According to some embodiments, the openings 93, 94 are configured to mitigate interference between the SMA wire 97 and the flat surface 96 in the vicinity of the resistance weld area 98. Although the openings 93, 94 are shown as fully through-shaped, in some examples the openings 93, 94 may be partially etched.

[0110] Figure 124 shows a fixed end of a bimorph arm according to one embodiment. The fixed end 195 of the bimorph arm includes a flat surface 196 for attachment to an SMA material, such as an SMA wire 197. The SMA wire 197 is fixed to the flat surface 196 by resistance welding in a resistance welding area 198. The resistance welding area 198 is formed using techniques including those known in the art.

[0111] Furthermore, the fixed end 195 includes a proximal end opening 193 and a tip end opening 194 separated by a resistance welding area 198. The proximal end opening 193 and the tip end opening 194 are formed using techniques including those known in the art.

[0112] Furthermore, the fixed end 195 includes an elongated opening 160 corresponding to a portion of the SMA wire 197. The elongated opening 160 may be removed to form wire clearance for the SMA wire 197. In some embodiments, the elongated opening 160 extends from the tip-side opening 194.

[0113] The proximal opening 193 and the tip opening 194 at least partially isolate the resistance welding area 198. The elongated opening 160 physically interrupts the flat surface 196 and defines the position of the SMA wire 197. According to some embodiments, the openings 194, 196 are configured to mitigate interference between the SMA wire 197 and the flat surface 196 in the vicinity of the resistance welding area 198. Although the openings 194, 196 are shown as fully through-shaped, in some examples the openings 194, 196 may be partially etched.

[0114] Figure 125 shows a fixed end 295 of a bimorph arm according to one embodiment. The fixed end 295 of the bimorph arm includes a flat surface 296 for attachment to an SMA material, such as an SMA wire 297. The SMA wire 297 is fixed to the flat surface 296 by resistance welding in a resistance welding area 298.

[0115] The resistance welding area 298 is at least partially separated by a nonlinear opening 294. In some configurations, the nonlinear opening 294 is U-shaped to physically separate up to 90% of the resistance welding area 298. The resistance weld 298 can be mounted on the weld tongue defined by the nonlinear opening 294.

[0116] The nonlinear opening 294 physically interrupts the flat surface 296 and defines the location of the resistance welding area 298. According to some embodiments, the linear opening 294 is configured to mitigate interference between the SMA wire 297 and the flat surface 296 in the vicinity of the resistance welding area 298. In some alternative embodiments, the resistance welding area 298 may be completely etched from the fixed end 295. Alternatively, the resistance welding area 298 may include a partially etched slot to reduce the contact area.

[0117] An alternative embodiment is shown in Figure 126. In this embodiment, the nonlinear opening 294 within the resistance welding region 298 is rotated 180 degrees from that shown in Figure 125. It should be understood that terms such as “top,” “bottom,” “upward,” “downward,” and the x, y, and z directions, as used herein for convenience, refer to the spatial relationships of multiple parts relative to each other, and not to any particular spatial or gravitational orientation. Therefore, the terms shall include the assembly of parts of the components, regardless of whether the assembly is oriented in a particular orientation shown in the drawings and described herein, inverted from that orientation, or any other rotational variation.

[0118] It will be recognized that the term “invention” as used herein should not be interpreted as meaning that only a single invention having a single essential element or group of elements is presented. Similarly, it will be recognized that the term “invention” may include several separate inventions, each of which may be considered a separate 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 embodiments of the invention can be achieved without departing from the spirit and scope of the invention. Furthermore, the techniques described herein may be used to fabricate devices having 2, 3, 4, 5, 6, or more, generally n, bimorph actuators and distortion actuators. Accordingly, it will be understood that the detailed description and accompanying drawings described above are not intended to limit the scope of the invention, and this should be inferred only from the following claims and their appropriately interpreted legal equivalents.

Claims

1. It is an actuator, The beam section and Fixed end and Ends of the load point and Equipped with, The beam portion is positioned between the fixed end and the load point end. The load point end includes a flat surface including a resistance welding area configured for attaching SMA material, which is part of the actuator.

2. The actuator according to claim 1, comprising an SMA material attached to the fixed end and the load point end.

3. The actuator according to claim 2, wherein the load point end includes a tip-side opening and a base-side opening separated by the resistance welding region.

4. The actuator according to claim 2, wherein the load point end includes an elongated opening corresponding to a portion of the SMA material.

5. The actuator according to claim 2, wherein the load point end includes a front end opening and a base end opening separated by the resistance welding region, and an elongated opening corresponding to a portion of the SMA material, the elongated opening extending from the front end opening.

6. The actuator according to claim 1, wherein the load point end includes a nonlinear opening that defines the resistance welding region.

7. The actuator according to claim 6, wherein the resistance welding region is completely etched from the load point end.

8. The actuator according to claim 6, wherein the resistance welding region is partially etched by the nonlinear opening.

9. The actuator according to claim 1, wherein the load point end further includes at least one radiating surface area extending from the resistance welding region.

10. It is an actuator, The beam section and Fixed end and A load point end, wherein the beam portion is positioned between the fixed end and the load point end, The SMA material attached to the fixed end and the load point end Equipped with, The aforementioned fixed end is, An actuator including a flat surface, including resistance welding of the aforementioned SMA material.

11. The actuator according to claim 10, wherein the fixed end includes a tip-side opening and a base-side opening separated by the resistance welding region.

12. The actuator according to claim 10, wherein the fixed end includes an elongated opening corresponding to a portion of the SMA material.

13. The actuator according to claim 10, wherein the fixed end includes a front end opening and a base end opening separated by the resistance welding region, and an elongated opening corresponding to a portion of the SMA material, the elongated opening extending from the front end opening.

14. The actuator according to claim 10, wherein the fixed end includes a nonlinear opening that defines a resistance welding region for the resistance welding.

15. The actuator according to claim 14, wherein the resistance welding region for the resistance welding is completely etched from the load point end.

16. The actuator according to claim 14, wherein the resistance welding region for the resistance welding is partially etched by the nonlinear opening.

17. The actuator according to claim 10, wherein the load point end further includes at least one radiating surface area extending from the resistance welding region.

18. It is an actuator, Bass and, One or more bimorph arms and Equipped with, The one or more bimorph arms are The beam section and Fixed end and Ends of the load point and Includes, The actuator comprises a beam portion positioned between the fixed end and the load point end, wherein at least one of the fixed end and the load point end includes a flat surface including a resistance welding region.

19. The actuator according to claim 18, wherein at least one of the fixed end and the load point end includes a tip-side opening and a base-side opening separated by the resistance welding region.

20. The actuator according to claim 18, wherein at least one of the fixed end and the load point end includes an elongated opening corresponding to a portion of the SMA material.

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