KR20100116584A - Optical lens image stabilization systems - Google Patents

Abstract

The present invention provides optical systems, devices, and methods that utilize one or more electroactive polymer actuators to stabilize an image produced by the device or system.

Description

Optical lens image stabilization system {OPTICAL LENS IMAGE STABILIZATION SYSTEMS}

The present invention relates to an optical lens system, and more particularly to a system employing an electroactive polymer transducer that adjusts the lens to provide autofocus, zoom, image stabilization and / or shutter / aperture functions.

In conventional optical systems such as digital cameras, motors and solenoids are used as a power source to move optical elements, such as gears and cams, acting on the lenses, to provide focus, zoom, and image stabilization (also called anti-shake). to provide. Many of these disadvantageous systems have disadvantages such as high power consumption, long response time, limited accuracy, and high space consumption.

Advances in miniaturization technology have led to the development of high-quality, high-performance, lightweight portable devices and the ever-increasing demands of consumers for more advanced products. One such example is the development of cellular phones, including cameras, often referred to as camera phones. Many of these camera phones employ entirely mechanical lens modules with small form factor lenses, but this approach requires variable or autofocus, zoom and image stabilization functions because of the large number of operating components required. It does not provide. For example, the zoom function requires a combination of the lens element, the motor, and a cam mechanism for converting the rotational motion of the motor into linear motion to adjust the relative position of the lens and the associated image sensor to obtain the desired magnification. In addition to the motor and cam mechanism, a plurality of reduction gears are used to precisely control the relative position of the lenses.

In order to perform various autofocus and zoom operations in digital still cameras and camera phones, a magnetic force placed by a magnet with a length greater than the length of the optical axis coil (commonly referred to as the "voice coil") Electromagnetic actuators that include a generating coil are typically employed. This voice coil technology has been widely adopted because it enables the implementation of compact and lightweight optical lens systems. However, the disadvantages of small, lightweight cameras, especially those with long exposure times and high resolution sensors, are that basically camera shake due to hand jitter has a greater impact on the quality of the picture (ie, blurring). Is the point. To compensate for camera shake, gyroscopes are often used for image stabilization. Gyroscopes measure pitch and yaw, but cannot measure rolls, ie rotation about the axis defined by the lens barrel. Conventionally, two single-axis piezoelectric or quartz gyroscopes have been used with a number of external elements to achieve a full range of image stabilization. InvenSense offers an integrated dual-axis gyroscope using image-stabilized MEMS technology that offers miniaturization.

While variable focus, zoom, and image stabilization features are available in camera phones and other optical systems with relatively small form factors, these features substantially increase the overall weight of these devices. Moreover, since it requires a large number of moving elements, the power consumption is quite large and the manufacturing cost increases.

Accordingly, there is a need to provide an optical lens system that overcomes the problems of the prior art. In particular, there is a need to provide a system in which the arrangement of mechanical interfaces between the lens and its operating structure can be highly integrated in order to reduce the form factor as much as possible. It would be a great advantage if such an optical system could reduce the complexity and manufacturing cost of the system by including minimal mechanical components.

The present invention aims to provide an optical lens system, in particular a system employing an electroactive polymer transducer that adjusts the lens to provide autofocus, zoom, image stabilization and / or shutter / iris aperture functions.

The present invention includes optical lens systems and devices and methods of using them. The system and devices include one or more Electroactive Polymer (EAP) based actuators integrated therein to adjust the parameters of the device / system. For example, one or more EAP actuators automatically adjust the focal length of the lens (autofocus), magnify an image focused by the lens and / or adjust unwanted movement of the lens system (image stabilization or shake). Can be configured).

One or more EAP actuators include one or more EAP transducers, and the one or more members are integrated with one or more lenses, sensing, and shutters / apertures of the target lens system / device. The lens portion (ie lens stack or barrel) comprises at least one lens. In certain embodiments, the lens portion generally includes a focusing lens element and an infinite focus lens element. The sensor unit includes an image sensor that receives an image from the lens unit of the device for digital processing by the image processing electronics. By activating the EAP actuator (s), i.

In one embodiment, an actuator assembly (including at least one EAP actuator) can be used to adjust the position of the lens stack along the longitudinal axis (Z-axis) relative to the sensor portion to change the focal length of the lens stack. In other variations, the same or different actuators may be used to adjust the position of one or more lenses in the stack relative to each other along the longitudinal axis (Z-axis) to adjust the magnification of the lens system. In another embodiment, the actuator is arranged in a planar direction (X-axis and / or Y-axis) relative to the lens portion to compensate for the unexpected movement imposed on the system, ie to stabilize the image imposed on the image sensor. It can be used to move the sensor part of the system part, and vice versa.

The invention may also include methods of using subject devices and systems to focus and / or magnify an image, or to offset unwanted movement of the device / systems. Other methods include methods of manufacturing the subject device and systems.

These and other features, objects, and advantages of the invention will be clearly understood by those skilled in the art through the detailed description of the invention, which is described in more detail below.

The invention is most clearly understood from the following detailed description in conjunction with the accompanying schematic drawings, and it can be considered that variations of the invention are possible from those shown in the drawings. In order to facilitate understanding of the present invention, the same reference numerals are used to indicate similar components commonly included in the drawings. The drawings include the following:
1A and 1B are cross-sectional and exploded views, respectively, illustrating an optical lens system of the present invention employing an electroactive polymer actuator configured to provide auto focus;
2A and 2B are schematic diagrams showing electroactive polymer films used in optical systems of the present invention before and after voltage application;
3 is a cross-sectional view showing another optical lens system of the present invention employing another type of electroactive polymer actuator for focus adjustment;
4A and 4B are cross-sectional and exploded views, respectively, illustrating different optical lens systems employing actuator combinations to control zoom and autofocus, respectively;
5A and 5B are perspective views showing alternative means for zoom control;
6a to 6c show step by step the operation of the transducer device in FIGS. 5a and 5b;
7A and 7B are cross-sectional and exploded views, respectively, illustrating another optical lens system of the present invention configured to provide auto focus and image stabilization functions;
8 is an exploded view illustrating the image stabilization cartridge of the lens system of FIGS. 7A and 7B;
9A and 9B are top and bottom views respectively illustrating the electrode configuration of the electroactive polymer transducer of the image stabilizing cartridge of FIG. 8;
10A and 10B are top and bottom views, respectively, illustrating another embodiment of an electroactive polymer transducer that can be used with the image stabilization cartridge of FIG. 8;
10C and 10D are top and bottom views respectively showing electroactive films employed in the transducers of FIGS. 10A and 10B;
11A and 11B are graphs showing passive stiffness and load response, respectively, of the lens system of FIGS. 7A and 7B;
12A is a perspective view showing a leaf spring biasing member usable for biasing an EAP autofocus actuator of the present invention;
12B and 12C are cross sectional and top views illustrating the optical lens system of the present invention in which the plate-shaped spring biasing member of FIG. 12A is effectively used;
13 is a sectional view showing another optical lens system of the present invention using an integrated plate spring biasing member;
14A and 14B are cross-sectional views respectively showing lens system housings with and without associated lens barrels including other types of integrated spring biasing members;
15A and 15B are perspective and cross-sectional views illustrating assembled lens barrel and flange assemblies usable with the lens system of the present invention in which the assembly provides an adjustable barrel design for focus adjustment;
15C is a diagram illustrating the use of a tool for adjusting the infinite focus parameter of the lens barrel assembly of FIGS. 15A and 15B;
16A and 16B are perspective and cross-sectional views illustrating another lens barrel assembly having an adjustable flange design for focusing;
17A and 17B are cross-sectional views illustrating lens systems having single-phase and two-phase actuator configurations, each providing a very compact, low lateral form factor;
18A and 18B are perspective and cross-sectional views illustrating an exemplary EAP actuator based lens displacement mechanism of the present invention;
19A and 19B are perspective and sectional views, respectively, illustrating different EAP lens displacement mechanisms usable in the present invention;
20A and 20B are perspective and sectional views, respectively, illustrating an EAP actuator and another lens displacement mechanism employing mechanical linkage;
FIG. 21 is a sectional view showing another hybrid lens displacement system of the present invention; FIG.
22A and 22B are perspective and cross-sectional views respectively illustrating the lens displacement mechanism of the “inchworm” type of the present invention;
23A and 23B are perspective and cross-sectional views, respectively, illustrating the lens displacement mechanism of the multi-stage “bugle” form of the present invention;
FIG. 24A is a sectional view showing an actuator cartridge of the lens displacement mechanism of FIGS. 23A and 23B;
24B-24F illustrate various positions of the actuator and associated lens guide rails during an operation cycle;
25A-25C are cross-sectional views illustrating the multi-actuator lens displacement system of the present invention;
26A and 26B are cross-sectional views showing deactivation and activation states of the lens image stabilization system of the present invention;
27A-27C are cross-sectional views illustrating another lens image stabilization system of the present invention in various activation states;
28 is an exploded view showing the aperture / shutter mechanism of the present invention suitable for use with the lens system as well as other known lens systems;
FIG. 28A is a side view showing a rotating collar of the shutter / iris mechanism of FIG. 28; FIG.
29A-29C are views showing a fully open, partially open, and fully closed state of the aperture / shutter mechanism of FIG. 28;
30A and 30B are cross-sectional views showing unimorph actuator films used in the lens displacement mechanism of the present invention;
31A and 31B are side views illustrating another lens displacement mechanism of the present invention in an inactive and active state, respectively, employing the unimorph actuator film of FIGS. 30A and 30B;
32A and 32B are side views illustrating another lens displacement mechanism of the present invention employing a unimorph actuator;
33A and 33B are diagrams illustrating the use of an EAP actuator having features that allow it to handle certain conditions, such as, for example, moisture in the environment in which the lens system is operated to optimize performance;
34 is a sectional view showing the lens displacement system of the present invention employing another configuration for handling ambient conditions;
34A and 34B are perspective and plan views illustrating an ambient condition adjustment mechanism of the system of FIG. 34;
35 is a sectional view showing another lens displacement system of the present invention having a lens position sensor;
36A is a perspective view showing other examples of mechanical parts of the shutter / iris mechanism of the present invention;
36B and 36C are views respectively showing the shutter / iris of FIG. 36A in the fully open and fully closed states; And
FIG. 36D is a perspective view illustrating the mechanism of FIG. 36A effectively coupled with an EAP actuator of the present invention. FIG.

Before describing the apparatus, system, and methods of the present invention, it will be understood that the present invention is not limited to a particular form or application. As such, the invention is primarily described in the context of a variable focus camera lens, while the optical systems can be used in microscopes, binoculars, telescopes, camcorders, projectors, glasses, as well as other forms of optical applications. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting, since the scope of the present invention will be limited only by the appended claims.

1A and 1B show an optical lens system of the present invention having an auto focus function. In the figure, a lens module 100 having a lens barrel 108 with one or more lenses (not shown) is shown in detail. An aperture 106 is provided at the end or front end of the lens barrel 108. An electroactive polymer (EAP) actuator 102 having an electroactive polymer film 120 is disposed outside the aperture 106. The film 120 is inserted outside by the frame faces 122a and 122b and in the center by the disc faces 104a and 104b, leaving the exposed annular section of the film 120. Hereinafter, the structure and function of the electroactive films will be described in more detail with reference to FIGS. 2A and 2B.

As shown in the schematic diagrams of FIGS. 2A and 2B, the electroactive film 2 comprises a composite material comprising a flexible electrode plate or a thin dielectric layer 4 sandwiched between the electrode layers 6. to form a capacitive structure. As shown in FIG. 2B, when voltage is applied to the electrodes, different charges in the two electrodes are attracted to each other, and this electrostatic attraction forces the dielectric layer 4 (along the Z-axis). In addition, the repulsion between the same charges in each electrode tends to spread the dielectric layer planarly (along the X- and Y-axes), reducing the thickness of the film. Thus, dielectric layer 40 orbits the change in electric field. Since the electrodes 6 are flexible, the shape changes with the dielectric layer. Generally speaking, the directional deflection refers to any displacement, expansion, contraction, distortion, linear or area strain, or any other deformation of a portion of the dielectric layer 4. Based on a form fit structure, for example a frame in which a capacitive structure is employed, this direction turning can be used to produce mechanical work. The electroactive film 20 can be pre-tensioned in the frame to improve the conversion between electrical and mechanical energy, ie pre-tensioning allows the film to orbit more and provide greater mechanical work. do.

When a voltage is applied, the electroactive film 20 continues to turn until the mechanical force is balanced with the electrostatic force that causes the turn. The mechanical force includes the elastic resilience of the dielectric layer 4, the flexibility of the electrodes 6, and any external resistance provided by the device and / or load coupled to the film 2. In addition, the result of the direction turning caused by the film as a result of the applied voltage also depends on the dielectric constant of the elastomeric material and numerous other factors such as its size and stiffness. The removal of the voltage difference and the induced charge returns to the inactive state as shown in FIG. 2A, causing an inversion effect.

The length L and width W of the electroactive polymer film 2 are much greater than the thickness t. In general, dielectric layer 40 has a thickness in the range of about 1 μm to about 100 μm and may be thicker than each electrode. It is desirable to select the elastic modulus and thickness of the electrodes 6 such that the additional stiffness given to the actuator is generally less than the stiffness of the dielectric layer having a relatively low modulus of elasticity of less than about 100 MPa.

Suitable electroactive polymer material classes for use with the optical system include, but are not limited to, dielectric elastomers, electroactive polymers, electron electroactive polymers, and ion electroactive polymers, and some copolymers. Suitable dielectric materials include, but are not limited to, silicones, acrylics, polyurethanes, fluorosilicones, and the like. Electroactive polymers have the properties of nonlinear reactions. Electron electroactive polymers generally change shape and dimensions by the movement of electrons in response to an electric field (primarily dry). Ion electroactive polymers are polymers whose shape and dimensions change due to the movement of ions in response to an electric field (mainly wet and electrolyte). Suitable electrode materials include carbon, gold, platinum, aluminum, and the like. Suitable films and materials for use with the diaphragm cartridges of the present invention are disclosed in US Pat. Nos. 6,376,971, 6,583,533, and 6,664,718, which are incorporated herein by reference.

Referring again to FIGS. 1A and 1B, the operational engagement of the lens barrel and stack 108 and the EAP actuator 102 enables autofocus of the lens assembly. The frame 122 is attached to the distal end of the housing 114 by bolts received in the holes 126b, while the disk or cap portion 104 of the EAP actuator 102 is attached to the lens barrel 108. Positioned or mounted at the distal end, the aperture 118 in the cap 104 is axially aligned with the aperture 106 to allow light to pass through the lens assembly. A biasing member in the form of a leaf spring mechanism 110 is operatively coupled between the lens barrel 108 and the frame 122 to preload the disc 104 in the direction of the arrow 125. Or deflection to provide a frustum-like structure. Such frustum-shaped actuators are described in detail in US patent application Ser. Nos. 11 / 085,798, 11 / 085,804, and 11 / 618,577, which are hereby incorporated by reference in their entirety. Preload or biasing ensures that the actuator 102 operates in the desired direction rather than simply wrinkle upon electrode activation. In addition to the illustrated leaf spring mechanism 110, the housing 114 has a wall recess 132 or the like to receive and operatively arrange one or more leaf springs with respect to the actuator 102. As shown in FIG. 7A, other biasing means, such as a simple positive rate of spring (eg, coil spring), may alternatively be used.

On the proximal end or back of the lens assembly or stack 108 is placed an image sensor / detector 116 (such as a charge coupled device (CCD)) which receives an image for digital processing by the electronic control unit 128. do. The focal length of the lens stack 108 is adjustable by selective operation of the EAP actuator 102 (where the axial position of one or more lenses is adjusted relative to the other lenses). Sensor 116 as well as actuator 102 may be powered by electrical coupling to power supply 130.

As shown in FIG. 1B, the complete camera assembly includes at least a shade or cover 112. Other components, such as infrared filters (not shown) commonly used in conventional lens systems, may be operatively included in the system.

3 shows another lens module 140 of the present invention. A cylindrical lens barrel 142 having one or more lenses 144 is included to be movable within the outer and inner housing members 146 and 148 having the distal end 142a and the proximal end 142b. The distal end portion 142a is disposed to slide through the opening of the outer housing 146, and the proximal end portion 142b is disposed to slide through the opening of the inner housing 148. The connection portion between the distal end portion 142a and the near end portion 142b defines an annular shovelder 150 on which the inner frame member 158 of the annular EAP actuator 152 is mounted. Actuator 152 has a double frustum structure defined by films 154a and 154b that are held in an unfolded state between inner frame members 158. The periphery of the raw film 154a is disposed between the outer housing 146 and the frame block or spacer 156, and the periphery of the near end film 154b is disposed between the inner housing 148 and the frame block 156. Instead of being deflected by the plate spring mechanism, the double frustrated structure film 154a provides a preload with respect to the actuator 152 in the direction of the arrow 155, using the lens barrel 142 in the same direction to focus the lens. Adjust (144). Unbiased film 154b may be an EAP film, while deflected film 154a may be an elastomeric webbing. Shoulder film 154a includes an electroactive polymer material, but may be used to sense position by a change in capacity, or in combination with film 154b, may provide a two-phase actuator. . In the latter case, when the film 154b is activated, the lens barrel 142 may move in the direction of the arrow 157, thereby adjusting the focal length of the lens 144 in the opposite direction.

In other variations of the invention, FIGS. 4A and 4B show an optical system 160 employing an actuator combination to control focus and zoom. The system includes a focus lens 164 having a focus stage received within the housing 182 and disposed within the lens barrel 162 and driven by the diaphragm actuator 166. The focus is adjusted by varying the distance between the lens 164 and the image sensor 180 in the same manner as described with reference to FIGS. 1A and 1B. The system 160 also includes a zoom disposed within the lens fixing 170 and under the lens cover 176 mechanically coupled to a pair of flat plate actuators 172a and 172b by reinforcements 174a and 174b, respectively. Lens 168. Each of these actuators 172a and 172b is formed by spreading the EAP film onto a common frame element 178 attached to the reinforcement. The zoom function is performed by changing the distance between the lenses 164 and 168. In general, focusing requires a movement of about 0.1 mm to 2.0 mm; Zoom requires about 5 to 10 times the stroke amount. Although not shown in the drawings, it may be contemplated that several sides of the combined frame may involve only diaphragm actuators or only flat plate actuators. In addition, a non-orthogonal frame structure may be used.

If there is a large amount of space available, it may be desirable to provide an EPAM zoom / focus engine suitable for longer zoom reciprocating distances in order to increase the operating range of the device. 5A and 5B are perspective views illustrating an alternative lens system 190 in which a set of pairs of plate actuators 192a and 192b are in a telescopic arrangement. In the figure, one of each pair is disposed on the opposite side of the lens carriage 194 fixed to the lens barrel 196 including the zoom lens 198. In operation, the platen actuator arrangement moves the lens barrel 196 and the zoom lens 198 along the focal axis for the image sensor 200 in the directions of arrows 202 and 204. 5A and 5B show the minimum and maximum zoom positions, respectively.

The manner in which the actuators are connected and operated can be clearly seen by the enlarged views of FIGS. 6A and 6C showing the various operating steps of the actuator stack of FIGS. 5A and 5B. Forward movement is accomplished by connecting a continuous output bar 208 to the actuator frame section 206. In this case, the innermost output bar is attached to the rod 210 to drive the zoom components.

7A and 7B, another optical lens system 300 of the present invention is shown that provides image stabilization in addition to auto focus. Lens module 302 includes a lens barrel 312 that holds one or more lenses. Here, the lens barrel 312 is illustrated as including four lenses (314a, 314b, 314c, and 314d), but may include less or more lenses. The lens assembly 314 is moved by an EAP actuator 320 that includes an EAP film 325 extending between the outer frame 322 and the inner disk or cap member 328. The outer frame 322 is fixed between the lower housing 324 and the upper housing 326. A biasing member in the form of a coil spring 332 is disposed about the lens barrel 312 and is operatively coupled between the rear end 334 of the lower housing 324 and the shoulder or flange of the lens barrel 312, such that the arrow 335 Preloading or deflecting the cap or disk 328 in the) direction provides the frustum shape to the EAP actuator 320.

The radial stiffness of the actuator disk member 328 and the resistance / deflection force imposed on the distal end of the lens barrel 312 (as opposed to the arrow 335) help to keep the barrel in the same center within the lens module 302. give. Moreover, the overall structure of the deflected EAP actuator effectively supports the lens barrel so that the lens barrel is unaffected by gravity, as shown in the graph of FIG. 11A showing the passive stiffness of such a lens positioning system. On the other hand, FIG. 11B shows the typical load response of the system after starting the reciprocation from the hard stop position.

A bushing wall 318 extends upwardly from the rear end 334 of the housing 324 to be seated between the coil spring 332 and the outer surface of the lens barrel 312. Bushing 318 serves as a linear guide for lens barrel 312 and, with flange 336, stops reciprocating motion at the maximum " macro " (close) focus position. Having a built-in travel or hard stop is useful for initial adjustment of the position of the barrel during the assembly of the system 300. The rigidity of the bushing wall 318 can prevent damage to the lens assembly in normal use. Moreover, the overall structure of the EAP actuator 320 provides shock absorption to the lens barrel. EAP actuators, bias springs, bushings, and the barrel design all work together to consistently maintain a radial arrangement for optimal performance of the lens system.

The frustum structure of the EAP actuator may be provided by another form of biasing member, such as the leaf spring mechanism 390 shown in FIG. 12A, in particular a configuration that provides a low side shape. The biasing mechanism 390 includes an annular base 392. The annular base 392 includes a radially extending fork tab 394 spaced from each other around the base 392 and angled upward at the bend point 396. 12B and 12C show a leaf spring biasing mechanism 390 employed as a biasing member in an optical lens system having a configuration similar to the system of FIGS. 7A and 7B. The base 392 of the leaf spring surrounds the lens barrel 312 below the flange 336, with each fork tab 394 having a lower side of the outer frame 322 which serves as a bearing surface. To combine. To provide a uniformly balanced and centered deflection, the leaf spring mechanism provides at least three tabs 394 at equal intervals. Further, to prevent unintentional rotational movement of the leaf spring 390, the branches or legs of the fork tab 394 are engaged in grooves located at each corner of the housing. The inner housing block 398 functions as a linear bushing or backstop relative to the lens barrel 312 when in the "infinity" (ie, closest) position.

The biasing member may be integrated into the lens barrel and / or housing structure of the optical lens system. 13 illustrates an example in which the structural portion 410 of the lens system of the present invention includes a lens barrel 412 disposed concentrically within the housing element 414. The bias member 416 is disposed across both between the lens barrel and the housing, where the biasing member is formed of a monolithic or integral structure (eg, by molding) associated with these elements, or between these elements. Can be inserted and provided. The latter configuration is shown and has an annular diaphragm 418 in convex form (viewed from above or from outside); However, it may alternatively take a concave form. Silicone, polyurethane, EPDM, other elastomers, or any low viscosity elastomers may be used as the material of the diaphragm 418. The diaphragm extends between the inner and outer sidewalls 420a and 420b which respectively support the outer lens barrel wall and the inner housing wall. Curved diaphragm 418 provides a negative rate spring mechanism. Examples of EAP actuators with negative deflection force are disclosed in US patent application Ser. No. 11 / 618,577, referenced above.

14A and 14B illustrate other methods of incorporating a spring bias of an actuator in the lens system. In FIG. 14A, the spring bias to be applied to the EAP actuator (not shown) is structurally integrated into the lower housing 324 of the lens system 300 of FIGS. 7A and 7B, for example, and the outer wall and bushing of the housing 324. Provided by two or more tabs 422 radially extending inwardly within the concentric gaps between the walls 318. Tabs 422 are bent or molded in such a way as to provide a spring bias when a load is applied. The lens barrel 312 is also integrally formed (by molding, etc.) and fixed together with the tabs 422 as shown in FIG. 14B.

The lens systems of the present invention may have one or more light filters in a suitable position relative to the lenses. Referring back to the system 300 of FIGS. 7A and 7B, the upper housing 326 includes a transparent or translucent lid 330 disposed therein for transmitting light rays. Alternatively, the upper housing 326 may be cast using a transparent / translucent material as a whole. In either case, the lid can function as a filter that prevents infrared wavelengths greater than about 670 nm from penetrating the lens assembly while generally transmitting visible wavelengths without loss. Alternatively or additionally, infrared filter 366 may be disposed proximate the lens assembly.

In addition, the lens system of the present invention has an image stabilization function. Referring again to FIGS. 7A and 7B, an image stabilization module 304 according to an exemplary embodiment is disposed with the lens module 302 proximate the lens module 302. The image stabilization module includes an image sensor 306 for receiving an image focused by the lens module 302 and associated electronics for processing such images. The image stabilization module 304 includes an EAP actuator 310 to compensate for any movement, ie, “shake,” in the xy plane of the image sensor 360 to keep the focused image clear. You may. In addition, a sensor for sensing such motion may also be provided with Z-axis correction.

EAP actuator 310 is a two layer EAP film transducer with "hot" and ground sides 338 and 348, as best seen in the exploded view of FIG. 8 and the top views of FIGS. 9A and 9B. It has a plate-like structure to include. EAP film 338 includes an elastomeric layer 342 and electrically insulated electrodes 340. Each of the electrodes 340 extends to a portion of the elastomer layer 342, leaving a central portion 362a of the elastomer layer 342. EAP film 348 includes an elastomeric layer 352 and a single ground electrode 350. The annular shape of ground electrode 350 may be attached to each hot electrode 340 and is formed to have a central portion 362b free of electrode material corresponding to a portion 362a of film 338. The two films together provide a transducer with four active quadrants (ie four active-ground electrode pairs) to provide a four-phase actuator; However, as described below with reference to FIGS. 10A-10D, four or more active portions may be included. Each quadrant, either individually or in conjunction with one or more other quadrants, is activated selectively to compensate for the response the system experiences in the xy plane (ie two degrees of freedom). Provide a range. Electrical tabs 344 are disposed between the two films, one for each hot electrode. A pair of grounded electrical tabs 346 are provided on the oriented outer surfaces of the EAP films 338 and 348. Tabs 334 and 348 connect the EAP actuator to a power supply and an electronic controller (not shown). The two-ply transducer film is disposed between the upper and lower frame members 345a and 345b which hold the EAP film in an expanded and tensioned state.

In addition, actuator 310 may include two disks 356 and 358 disposed at the centers of both sides of the composite film structure. Disks perform a variety of functions. The disk 356 provided on the outside of the hot electrode film 338 is maintained in planar alignment by the backplate or lid 360b in the annular space or the cut portion of the frame surface 354b. The disk 356 functions as a travel stop (prevents the film 338 from contacting the rear plate) and functions as an additional bearing support for the sensor. The disk 358 is provided on the outside of the film 348 to allow the disk 358 to transmit the movement of the actuator 310 to the image sensor 306 within the annular space of the cut portion of the frame surface 354a. It is maintained in planar alignment by the front plate or cover 360a, which also includes the cut portion. In order to facilitate the transfer of output actuator motion from the disk 358 to the image sensor 306, a linear bearing structure / suspension member 308 is provided therebetween. The structure / member 308 takes the form of a plate-like substrate 362 having a plurality of shock absorbing elements 364, such as, for example, spring tabs extending from the edge of the substrate 362. The shock absorbing element 364 functions as a shock absorber to optimize the output motion of the actuator 310. Substrate 362 may be in the form of a flex circuit with spring tabs 364 providing electrical contact between the image sensor 306 and its associated electronic controller to the actuator 310 (which is formed of a conductive material) Occation).

The image sensor 306, suspension member 308, and actuator 310 are nested together within the housing 316. The housing 316 is recessed on the distal side 368 to receive the lens module 302. On the proximal side 370 of the housing 316, the housing 316 is for receiving the electrical contact tabs 344 and 346 of the actuator 310 and / or the spring tab 364 of the bearing / suspension member 308. It has a notch or recess 372.

As mentioned in connection with the mention of the four-phase actuator 310, the image stabilizing actuator of the present invention may have any number of active regions that provide actuation of the desired phase. 10A-10D illustrate a three phase EAP actuator 380 suitable for use with the subject optical lens system of the present invention for at least image stabilization. Actuator 380 includes hot EAP film 384a with three electrode regions 386. Each region 386 affects about one quarter actuation of the active region of actuator 380. Ground EAP film 384b has a single annular ground electrode 388. When the single annular ground electrode 388 is packaged with the film 384a by the frame side 382a and 382b, it provides a ground side to each of the three active portions of the actuator 380. Such three-phase designs are more fundamental than mechanical and electrical four-phase designs, but three-phase actuators may not provide separate motion in the X- or Y-axis alone, requiring more complex electronic control algorithms.

Many manufactured hardware components have dimensions that fall within acceptable tolerances, and very small dimensional changes, such as in components and between related components, do not affect production yield. However, more precision is often required in devices such as optical lenses. More specifically, the lens assembly's position relative to the image sensor is in the “infinity” position (ie, in the “off” state) to ensure accurate focusing in use by the end user. It is important to be set to optimize the focus. For that reason, the infinity position is preferably adjusted during the assembly process.

15A and 15B illustrate an exemplary design configuration for adjusting the distance between the image sensor and the lens assembly to adjust the infinity position of the lens assembly, that is, to set the optimally focused infinity position during the manufacturing process. The lens barrel assembly 430 includes a lens barrel 432 and a detachable flange 434. The flange 434 is internally threaded to thread with an external thread 437 of the lens barrel 432. The flange 434 is provided with a radially extending tab 436 that projects from the designated opening 436 when disposed within the system housing 442, as shown in FIG. 15C. The rotating arrangement of the flange 434 is fixed relative to the lens barrel 432. The ridge 438 of the top cover 435 of the lens barrel 432 is provided with a groove or indentation 440 for receiving the end 446 of the adjustment tool 444. The adjustment tool 444 is in contact with the lens barrel 432 even when enclosed in the housing 442, and is provided with a screwed flange 434 fixed in the housing by a tab 436 and an opening 436. It is used to rotate the lens barrel 432 in any direction relative to it. This relative rotational motion causes the entire lens barrel assembly 430 to be linear or axial (in any direction based on the direction of rotation of the lens barrel) relative to the image sensor (not shown) and other fixed components within the lens system. Move it.

16A and 16B show another lens barrel configuration 450 for adjusting (at least in part) the lens assembly. The difference from the configuration of FIGS. 15A-15C is that the flange 456 is movable relative to the lens barrel which is rotated and fixed when operably seated in the housing 452. The lens barrel is fixed by a bumper or protrusion 460 extending radially from the outer wall of the lens barrel. When the lens barrel is seated in the system housing 452, the bumper 460 is disposed in an opening or window 458 of the housing wall, which prevents rotational movement of the lens barrel. An outer perimeter of the flange 456 is provided with an indentation 462 configured to engage an adjustment tool (not shown). The housing 452 is provided with a window 464 through which the peripheral edge of the flange 456 is exposed. Using an adjustment tool, the flange can rotate in either direction as needed. As with the previously described configuration, the relative motion of the flange relative to the lens barrel moves the entire lens assembly linearly or axially relative to the image sensor (not shown). Both configurations provide a convenient and easy way to adjust the infinity position of the lens assembly during final assembly of the lens system.

17A and 17B illustrate lens systems of the present invention that have a simpler, lower lateral shape design in which lens 472 (the farthest lens of a single lens or a plurality of lenses) is integrated directly into the EAP actuator and optionally disposed. Two other embodiments are shown.

The lens system 470 of FIG. 17A employs a single phase actuator that includes outer frame members 274 and 476, respectively, with an EAP film 478 extending therebetween. The lens 472 is disposed concentrically and fixed in the inner frame 474 so that output movement by the actuator is imposed directly on the lens 472. The single phase actuator is deflected toward the front side 472a of the lens by a dense coil spring 480 disposed within the frustum space defined between the inner frame 476 and the backplate 482. The backplate acts as a hard stop at the maximum "macro" (near focus) position. When the actuator is in the " off " state, the lens 472 is in the macro position, and when activated, the lens moves toward the infinity position in the direction of the arrow 488. In lens positioner applications that operate only in macro position, the initial macro setup improves the reliability of the system by eliminating unnecessary displacement ranges.

A two-phase lens system 510 having a similar low side shape structure is shown in FIG. 17B. Here, the EAP actuator includes two layers or diaphragms that deflect each other. The upper or rear actuators include an EAP film 494 extending between the inner and outer frames 490a and 490b, and the lower or front actuators extending between the inner and outer frames 490a and 492b. ). The inner frames 490a and 492a are coupled to each other, while the respective outer frames 490b and 492b are spaced apart from each other by the intermediate housing member 500, and the intermediate housing member 500 and the upper housing member 498 and the lower portion are separated from each other. Disposed between the housing member 502. Lens 472 (having a low lateral shape of the frustum shape) is disposed concentrically within the combined inner actuator frames. In two active actuators, each provides a bias to the other active actuator and enables two-phase or bidirectional movement of the lens. Specifically, when the lower actuator is activated while the upper actuator is off, the bias by the upper actuator moves the lens 472 in the direction of the arrow 504, and in a similar manner, while the lower actuator is off. When the upper actuator is activated, a bias by the lower actuator moves lens 472 in the direction of arrow 506. In this case, the lens 472 may have a 2x (2X) round trip distance compared to the single phase system 470. This double diaphragm configuration can make any one of the actuators passive, ie, always off, to function as a single phase actuator. In either case, the double diaphragm actuator provides a very low side shape form factor for the lens system.

The travel / stroke of the lens for auto focus or zoom can be increased (and decreased) by employing additional structural components that enable lens movement. This movement can affect the absolute displacement of a single lens or lens stack and / or the relative movement between the lenses in the lens assembly. Additional factors affecting this movement may include one or more EAP actuators, mechanical connections, or the like, or combinations thereof, integrated or coupled to the lens barrel / assembly.

18 and 19 are perspective views illustrating an exemplary lens displacement mechanism of the present invention in which multiple EAP actuators / transducers are stacked in series to amplify the stroke output shown by arrows 525 and 535, respectively. The transducers can be combined and operated together in the desired configuration to achieve the desired output.

The lens displacement mechanism 520 of FIGS. 18A and 18B includes a plurality of doubles comprising two opposing concave transducer diaphragms 526 including an inner frame or caps 532 in which each actuator device 528 is operated together. A frustum EAP actuator 528 device is provided. The outer frames 534 of the actuators operate simultaneously or are coupled to the outer frames 534 of adjacent actuators. The outermost outer frame 534a is mounted to a lens frame 524 having a lens 522 disposed therein. The outermost outer frame 534b is disposed at the far end from an image sensor module (not shown).

19A and 19B show a similarly functioning lens in which each of the plurality of EAP actuator devices 548 has an inverted configuration in which the transducer diaphragms 544 include concave surfaces facing inward with the outer frame 538 actuated simultaneously. Displacement mechanism 540 is shown. The inner frames 536 of the actuators are simultaneously operated or coupled to the inner frames 536 of adjacent actuators. The outermost inner frame 536a serves to hold the lens concentrically therein. The innermost internal frame 536b is disposed at the far end from an image sensor module (not shown).

In either design, the greater the level of the actuator, the greater the stroke potential. Furthermore, one or more actuator levels in the stack can be used for zoom applications in which additional lenses are integrated at various actuator levels and jointly operated as an endless focus lens assembly. Additionally or alternatively, one or more transducer levels may be provided for sensing—as opposed to actuation—to facilitate active actuator control or operation verification. In either of these operations, any form of feedback approach, such as a PI or PID controller, may be employed in the system to control the actuator position with high accuracy and precision.

20A and 20B, another lens displacement mechanism 55 is shown utilizing the EAP base or components 552 in cooperation with the mechanical lens driver or components 554. Here, the EAP unit 552 is used to drive the lens driver 554. The EAP portion 552 allows the inner frames 555a and 555b of the coupled transducer to be relatively movable along the optical axis 576, while the outer frames 556a and 556b are positioned between the lower housing portions 558a and 558b. And a double frustum actuator maintained at. As described above, the actuator may be configured as a two-phase actuator that enables active movement in both directions along the optical axis 576 or a single-phase actuator that is movable up / down along the optical axis.

The mechanical portion 554 of the displacement system 550 includes first and second driver plates or platforms 560 and 564 interconnected by connecting pairs 566a and 566b and 568a and 568b. Each plate has a central opening to contain a lens (not shown). The driver plates cooperate to provide an infinite focal lens assembly that adjusts the magnification of an infinite focal lens (not shown) disposed in the center of the lens opening 578 in the upper housing 574 as it moves along the infinite focal axis. Only two zoom displacement plates are provided, but any number of plates and corresponding lenses may be employed.

The connection pairs provide scissor jack movement to move the second driver plate 564 along the optical axis in response to a force acting on the first driver plate 560. As will be apparent to those skilled in the art, such scissor movement causes the second driver plate 564 to move at a faster speed than the first driver plate 560. Here, the rate of movement between the first plate and the second plate provides the telescoping effect. Plates 560 and 564 are guided by sliding along linear guide rods 572 extending between lower housing portion 558a and upper housing 574. Upon activation of the actuator portion 552, the cap 555a is moved to apply an upward force to the proximal end 562 of the driver plate 560. This drives the first plate 560 to move the connection pairs to drive the second plate 9564 at the selected higher travel speed. Although scissor connections are shown, other types of connections or mechanical arrangements may be used to move one plate at a proportionately greater travel speed and distance than the other.

21 shows another hybrid (actuator-connected) lens displacement of the present invention wherein the actuator portion 582 includes a single EAP transducer 584 deflected upward along the optical axis 588 by a coil spring 586. A cross-sectional view illustrating mechanism 580 is shown. Here, instead of the coil spring 586, any spring biasing means (eg, plate spring) can be employed. Upon activation of the actuator, the cap 590 drives the coupling mechanism 596 to move the first driver plate 592 which moves the second driver plate 594 upward along the optical axis 588.

Referring to Figures 22 and 23, two different lens displacement mechanisms of the present invention employing heterogeneous structures are shown. The lens displacement mechanisms move each lens assembly / barrel in a stepwise or “inchworm” manner using two types of actuator mechanisms.

The lens displacement mechanism 600 of FIGS. 22A and 22B performs two types of actuation movements (“thickness mode” actuation and planar actuation) to achieve the magnetic displacement of the lens assembly / barrel 602. Adopt. Lens barrel 602 holds one or more lenses (not shown) that form an endless lens assembly for zooming. Barrel 602 includes a bushing 606 extending laterally from an outer surface. The bushing 606 is coupled so as to rub against the guide rail 604 extending between the upper and lower actuation portions 608a and 608b. Actuation elements of mechanism 600 include a bottom 608a and a top 608b. Each actuator portion includes an actuator stack having a thickness type actuator EAP film 610 and a planar actuation EAP film 612. The films are separated from each other and are surrounded by a layer of flexible material, such as a visco-elastic material, which preferably has a very low viscosity and durometer rating to form the actuator stack 608a. 22A shows electrode layer patterns 610a and 612a as seen through the cut plane of actuator stack 608a. Center hole or gap 616 extends through stack 608a to deliver the focused image to an image sensor / detector (not shown).

In operation, activation of the planar actuator EAP film 612 occurs while the trailing or lower ends 604a of the guide rail are engaged with the film stack 608a (or at least the actuator layers 614b and 614c at substantially right angles). The ends 604a move laterally away from each other in directions opposite to each other, for example in a direction 605 perpendicular to the longitudinal direction of the axis of the guide rail 604. The front ends or the top ends 604b of the guide rails are fixed. While in position, this movement causes the guide rails 604 to be supported by the bearing 606, thereby rubbing the position of the lens barrel 602 by friction on the rails 604. Of the film 612 Deactivation pulls the rail back to a neutral position or to a position perpendicular to the film stack 608a.The thickness actuation actuates the guide rail in the axial direction 607 by friction with the guide rail 603. Combined, the lens barrel 602 is moved in the same direction to adjust the focal length of the lens assembly More specifically, when the EAP film 610 is activated, the film stack 608a is bent to guide rail 604. Axially move the lens barrel 602. As the lens barrel 602 is advanced, a friction support surface (not shown) is arranged to engage the outer surface of the barrel such that the frictional engagement is on the rail 604 by the barrel bushing 606. The frictional engagement of the supporting surface on the wall of the barrel overwhelms the bushing on the guide rail, so that when the thickness method EAP film 610 is deactivated and the guide rail returns to the inactive position, the lens barrel Is maintained in the advanced position, and the lens assembly can be moved in the opposite axial direction by reversing the order of the planar thickness actuation.

Optionally, an upper actuation portion 608b may be employed to adjust the relative position or angle of the rail 604 and / or increase the potential round trip distance of the lens barrel 602 in either axial direction 607. have. In this example, the actuator 608b is configured to provide a planar actuation that adjusts the position of the rails for the purpose of frictionally mating the rails with respect to the bushing 606. In particular, the actuator stack 608a includes a planar actuation EAP film 618 disposed between layers 620a and 620b, which may be formed of the same material as the layers 614a through 614c of the lower actuator 608a. The composite structure has holes or gaps extending therethrough to allow light rays passing through a focus lens (not shown) to reach the zoom or infinity lens assembly 602. Preferably, planar sections 608a and 608b act to simultaneously hold guide rods 604 that are parallel to each other.

The upper actuator 608b may be employed in place of the planar actuator of the lower actuator 608a to provide angular displacement of the rails, or the planar actuator of the lower actuator 608a to laterally displace both ends of the rails. It can be used in tandem with the ministry. Such cooperative actuation is controlled to precisely adjust the angular disposition of the rail, or alternatively, keep the rails perpendicular to the plane of the respective actuators (ie, the rails remain parallel to each other), The bushing 606 may be controlled to provide a lateral displacement (in the opposite or opposite direction of the lens barrel 602) sufficient to obtain frictional support. The upper actuator 608b may have the thickness actuation functions described above to increase the axial movement of the guide rails. Although all rails have been described as moving, the present invention also includes variations of the lens displacement mechanism configured to move a single rail or more than two rails.

23A and 23B illustrate another lens displacement mechanism 625 that employs a bugle-shaped actuation motion. The mechanism 625 houses a lens assembly comprising a plurality of lens stages 626a, 626b, 626c, and 626d, each having a cutout 627 holding a lens (not shown). Those skilled in the art may find that fewer or more lens stages may be employed than the four lens stages shown, which stages retain the lenses used for focusing, zooming or simply providing a path of light. I will understand. Moreover, not all stages need to be movable and may be secured to the mechanism housing or strut 628. In the variant shown, for example, the first and fourth stages 626a and 626d are fixed while the second and third stages 626b and 626c are movable. The four lens stages are spaced parallel to each other by linear guide rails 642 fixed and extending from the top to the lower lens stages 626a and 626d. The movable lens stages 626b and 626c are linearly movable along the guide rails 642 through the bearings 648.

The actuation portion of the displacement mechanism 625 includes first / top and second / bottom actuator cartridges 630a and 630b. The configuration of the cartridge 630a is shown in FIG. 24A. In the figure, two actuators are provided that are stacked in series with each other—a single phase linear actuator 632 and a two-phase planar actuator 634. Each actuator includes an EAP film extending between inner and outer members 638a and 638b, each inner member 638a operating simultaneously, and each outer member 638b having a spacer disposed therebetween. 640 is combined. In the variant shown, the EAP film of each planar actuator 634 is divided into at least two separately activatable portions 636a and 636b to provide two-phase (or three-phase or more) actuation. In this variation, each linear actuation 632 includes a monolithic EAP film 636c that is actuable as a whole. Two (top and bottom cartridges) single phase linear actuators 632 cooperate to form a two-phase linear actuator. Here, by the push rod 644 holding the actuators in tension with respect to each other, the lower linear actuator is deflected by the upper linear actuator, and vice versa. As a result, when the linear actuator 632 is passive, each planar actuator 634 has no applied out-of-plane force. The output motion of the inner members 638a of both actuators 632 and 634 is controlled to represent axial motion and / or planar motion, respectively, as indicated by arrows 640a and 640b, so as to represent the desired actuation cycle or sequence. Can be provided. The configuration of the upper cartridge 630b is the same as that of the lower cartridge 630a, but is directed toward the lower cartridge 630a with the concave surface of the cartridge facing out.

A connection in the form of a pushrod 644 extends between the inner opposing output members 638a of the actuator cartridges 630a and 630b, sliding through the axially aligned holes in the respective lens stages. Clutch or brake mechanisms 646a and 646b, which are selectively associated with the push rod to fix the axial position of each lens stage, are adjacent to the holes in the movable stages 626b and 626c, and disposed opposite to each other in diameter. do. Clutch mechanisms 644a and 646b may include any suitable configuration, including, for example, a tooth that cooperates with a corresponding support on the friction support surface or pushrod 644.

In operation, the selective actuation of the linear and planar actuators 632 and 634 of the two actuator cartridges 630a and 630b causes the periodic movement of the pushrod 644 to step the lens stages 626b and 626c step by step. To be moved. This step or "bugle" motion is schematically illustrated in Figures 24B-24F. FIG. 24B shows the guide rail 644 in the neutral position, ie not engaged with the lens stage 626b or lens stage 636c, when both actuators 632 and 634 are inactive. In order to move the lens stage 626b forward, the first portion 636a of the EAP film of each planar actuator 634 (ie, upper and lower portions of FIGS. 23A and 23B), as shown in FIG. 24D, Is activated to move the pushrod 644 laterally from the neutral position to engage the clutch mechanism 646a (not shown). Next, as shown in FIG. 24D, the linear actuator 632 is activated, while the first portion 636a of each planar actuator 634 remains flat and the output member 638a is out of plane. -of-plane). This out-of-plane motion pushes or lifts the push rod 644, thereby moving the lens stage 626b forward. Once moved to the desired axial position, push rod 644 is disconnected from clutch 646a by deactivating first EAP portion 636a of each planar actuator 634, as shown in FIG. 24E. Finally, as shown in FIG. 24F, each linear actuator 632 is deactivated and pulls push rod 644 to a neutral position. In order to move the lens stage 626c, the above process is repeated but activates the second EAP portion 636b of the planar actuator 634 in place of the first EAP portion 636a. Individually activatable phases, ie EAP film portions, are added to each planar actuator 634 with an additional clutch mechanism so that the lens displacement mechanism can move both lens stages or, optionally, more stages side by side. have.

25A-25C show another lens displacement system 650 with focus and zoom functions. System 650 includes two integrated single phase, spring-biased actuators—one comprising a single frustum diaphragm configuration 652 and the other comprising a double frustum diaphragm configuration 654. The actuator includes a lens barrel structure 656 that houses the focus lens assembly 658. Infinite lens assembly 660 received in barrel structure 662 is disposed closest to lens assembly 658 along the focal axis of the system. The two lens barrels 656 and 662 are deflected in opposite directions by the coil spring 664. The radially extending side structure to which the outer frame or output members 668a and 668b of the actuators 652 and 654 are coupled, respectively, further integrates the two actuators. EAP film 670 extends between an outer frame 668a and a corresponding inner frame or output member 672 mounted to the distal end of lens barrel 656 that focuses actuator 652. The first EAP film 676a is then spread out between the outer frame 668a and the corresponding inner frame or output member 674 mounted to the distal end of the lens barrel 662. The second EAP film 676b is spread between the inner frame 674 and the grounded outer frame or output member 668c to form the double diaphragm structure of the zoom actuator 654. The second coil spring 678 deflects the outer frames 668a and 668b coupled from the ground outer frame 668c.

As shown in FIG. 25A, all the phases of the system actuators are passive with focus at the "infinity" position. Adjusting the system focus includes activating the EAP film 670 of the focus actuator 652, as shown in FIG. 25B. Preload applied to lens barrel 656 advances lens barrel 656 in the direction of arrow 680 to provide a reduced focal length. The displacement amount in the lens barrel 656 can be controlled by controlling the amount of voltage applied to the actuator 652. The zoom actuation is similar, but as shown in FIG. 25C, activation of the actuator 654 is applied to both the EAP films 676a and 676b to advance the lens barrel 662 in the direction of the arrow 682. There is a difference in that. As with the focusing, the range of zoom displacement can be controlled by adjusting the amount of voltage applied to the actuator 654. In order to obtain a larger amount of displacement, additional actuator stages arranged in series can be provided. The actuator 654 may be operated in two phases in which the two diaphragms are activated independently of each other to provide incremental zoom displacement. While the drawings illustrate independent operations of the focus (FIG. 25B) and zoom (FIG. 25C) lens assemblies, both may be operated simultaneously or controlled side by side to provide the desired combination of focus and zoom in a particular lens application.

26A and 26B illustrate another displacement mechanism 690 suitable for lens image stabilization. The actuator mechanism has a multiphase EAP 696 that extends between the outer frame mount 692 and the central output disk or member 694. The output disk 694 is mounted to a pivot 698 that deflects the disk out of plane. During stop, as shown in FIG. 26A, all phases or portions of multiple phases are passive, and output disk 694 is horizontal. When a selected portion or portions of the films 696a (of any number of portions that are individually activatable) are activated, the deflected film loosens in the activated region 696a, distributing the force on the output platform 694. This results in a balance and causes the platform 694 to tilt as shown in FIG. 26B. The various activatable portions are selectively activated to provide a three-dimensional displacement of the image sensor or mirror (not shown, but disposed on top of the central disk or output member 694) in response to system shake.

The displacement mechanism of FIGS. 26A and 26B can be further modified to compensate for unintended z-direction motion in the image sensor. This displacement mechanism 700 is shown in FIGS. 27A-27C, and instead of ground mounting the output member 704 of the actuator in a pivoted manner, a spring biasing mechanism 708 can be used. In addition, by using a multi-phased film 706, the actuator output disk 694 when fewer film portions than one film 706a or phases are activated, as shown in FIG. 27B. Undergoes asymmetric tilting and axial translation. If all the film portions 706 are activated simultaneously or some are activated to provide a symmetrical response, as shown in FIG. 27C, the output member 704 is capable of purely linear displacement in the axial direction. Will suffer. The magnitude of this linear displacement can be controlled by adjusting the voltage applied to all phases or by selecting a relative number of film portions that are activated at the same time.

In addition, the present invention may provide a shutter / iris mechanism for use with an image / optical system as disclosed herein. Here, it is necessary or desirable to close the lens iris (shutter function) and / or to control the amount of light transmitted to the optical element or component (aperture function). FIG. 28 illustrates this shutter / iris system 710 of the present invention employing an EAP actuator 712 to operate a plurality of cooperating plates or blades 724 to regulate the passage of light through an imaging pathway. To show. Actuator 712 has a planar configuration with two-phase EAP films 718a and 718b extending between outer and inner frame members 714 and 716. Here, the inner frame member has an annular opening 715 for passing light. Only two film portions 718a and 718b are described in this embodiment, but a multiphasic film may be used. The mechanical / operating components of the shutter / aperture are housed in a cartridge with top and bottom plates 720a and 720b, each of which has openings 725a and 725b for passing light.

The iris blade 724 has a curved or arcuate teardrop shape. Their annular alignment remains within the overlapping planar alignment. The blades extend upwardly through the wider ends of the blades 724 and are joined upwardly to correspond to holes defining pivots or fulcrum points on which the blades pivot. 736 is mounted to the bottom plate 720 in a pivoting manner. The tapered ends of the blades face in the same direction, with their concave sides defining the lens aperture. The opening size of the lens stop is changed by selectively pivoting the blade 724. Each of the blades 724 includes a cam follower slot 730, through which a different group of camping pins 732 extends from the bottom surface of the rotating collar 722 disposed on the opposite surface to the blade 724 ( As shown in FIG. 28). The cam follower slot 730 is curved to provide the cam pin 732 with the desired arcuate reciprocating path as the collar 722 rotates to orbit the curved blades 724 around the support point of the blade. It is formed into a mold. A pin 726 extending from the top of the collar 722 or from the side toward the actuator protrudes through the opening 725a of the upper cartridge plate 720a, so that the hole (in the inner frame member 716 of the actuator 712) 717). Selective activation of the actuator two-phase film 718 causes the inner actuator frame 716 to move in the opposite direction from the plane to the side. The output movement of the actuator through the pull / push of the collar pin 726 rotates the collar 727, thereby rotating the cam pins 732 in the cam slot 730 in the respective aperture blades 724. Accordingly, the blades are pivoted to move the tapered ends of the blades closer to or farther from each other to achieve a variable aperture opening. This is best shown in the top view of the cartridge 723 of Figure 29B. The size of the aperture opening varies between fully open (FIG. 29A) and fully closed (FIG. 29C) to act as a lens shutter.

36A-36D illustrate another aperture / shutter mechanism 840 of the present invention. Mechanism 840 includes a plate-like base 842 on which one stop is mounted to pivot point 845 in a diaphragm / shutter blade 844. Pivot movement of the blade 844 moves back and forth the free end of the blade in planar view above the light barrel and image aperture 854. The movement of the blade 844 is realized by the pivoting movement of the lever arm 846 including a free end movably received in the notch 856 in the interior edge of the blade 844. . Lever arm 846 is pivotally mounted to base 842 at pivot point 852a. A flexure 848 integrally coupled or integrally formed with the lever arm 846 extends between the first pivot point 852a and the second pivot point 852b. The tab 850 extends inward from the center of the flexure 848 toward the aperture 854. Blades, lever arms, and flexures may implement aperture 854 in a normal open or normal closed state.

As shown in FIG. 36C, the movement of the tab 850 toward the aperture 850 in the direction of the arrow 860a directs the flexure 848 in the same direction. This operation pivots lever arm 846 in the direction of arrow 860b so that the free end of the lever arm moves toward pivot point 845 within notch 856. As a result, the blade 844 may pivot in the direction of the arrow 860c to cover the diaphragm 854. This actuation is accomplished by the actuation of actuator 856 mounted or stacked on top of the moving components of mechanism 840, as shown in FIG. 36D. Actuator 856 includes a two-phase EAP film 860a and 860b configuration similar to that of actuator 710 of FIG. 28, extending between outer and inner frame members 858a and 858b, respectively. The free end of the tab 856 is mechanically coupled to the inner frame member 858b. Based on the direction of actuator 856 relative to shutter mechanism 840 shown in FIG. 36D, activation of EAP section 860a alone pushes tab 850 out, while activation of EAP section 860b is Pull the tab 850 inside alone.

As shown, mechanism 840 basically functions as a shutter as aperture 854 opens or closes. By aligning with the aperture 854 when the blade 844 is in the closed position, by providing a hole 862 (shown in dashed lines in FIG. 36A) in the blade 844 with a diameter smaller than the diameter of the aperture 854. The mechanism can function as an aperture mechanism with two settings-one of which places the blade in the open position, allowing more light to pass through the aperture 854 to reach the lens module, and the other. Is to cover the iris with a blade, passing light through the smaller holes 862.

Other lens displacement mechanisms enable movement of the lens or lens stack by using actuators that employ unimorph film structures or composites. 30A and 30B show cross sections of a portion of this film structure 740. The film structure includes an elastomeric dielectric film 742 attached to a film backing or substrate that is relatively rigid than the dielectric film 742, that is, has a higher modulus of elasticity. These layers are disposed between the flexible electrode 746 on the exposed side of the dielectric film 742 and the rigider electrode 748 on the exposed side or inside the rigid film backside 744. The composite structure 740 deflects only in one direction. In particular, as shown in FIG. 30B, when the film structure 740 is activated, the dielectric film 742 is compressed to laterally displace such that the structure is bowed or arcuated in a direction away from the substrate 744. The biasing imposed on the structure is achieved in any known manner, including as described in WO 98/35529. Hereinafter, some lens displacement mechanisms of the present invention employing such unimorphic EAP actuators are described.

The lens displacement system 750 of FIGS. 31A and 31B includes a lens barrel or assembly 754 coupled to an actuator mechanism using the unimorph EPA film structure 752. The selected area or length of the film structure 752 extends between the lens barrel 754 and the fixed base member 756. The film structure may be a monolithic piece that surrounds the lens barrel, such as a single phase structure or a skirt that provides a multi-phase action including multiple addressable regions. Alternatively, the actuator may include a number of individual pieces of film that can be configured to be addressed jointly or independently. In another variant, the more rigid film side or layer (ie, substrate side) faces inwardly such that the film is deflected outward. As shown in FIG. 31B, depending on the activity of the film, the film extends in a direction away from the fixed side, ie in a biased direction extending the film away from the base member 756, in the direction of the arrow 758. The lens barrel 754 is moved. Various parameters of the film composite, such as film area / length, variation elasticity between the EAP layer and the substrate layer, etc., may be adjusted to provide the desired amount of displacement that affects the focus and / or zoom motion of the lens system. Can be.

The lens displacement mechanism 760 of FIGS. 32A and 32B also utilizes a unimorph film actuator. System 760 includes a lens barrel or assembly 762 mounted to lens carriage 764 disposed on guide rail 766. Actuator 770 includes folded or laminated unimorph film sheets joined together in a series manner. In the illustrated embodiment, each unimorph sheet is assembled with a more flexible side 772a facing the lens barrel and a rigid side facing away from the lens barrel, but vice versa is also applicable. As shown in FIG. 32A, when all the actuator sheets are inactive, the stack is most compressed positionally, ie the lens barrel 762 is placed in the closest position. In the context of a focusing lens assembly, this position provides the longest focal length, while in the context of an afocal lens assembly, the zoom lens is placed in a macro position. Activation of the one or more sheets 772, collectively or independently, positions the lens barrel 762 in the direction of the arrow 765 to adjust the focus and / or magnification of the lens system.

Under certain environmental conditions, such as high humidity and extreme temperature environments, the performance of the EAP actuator may be affected. The present invention addresses these ambient conditions in conjunction with features that can be incorporated into the EAP actuator itself, or otherwise is assembled within the system without increasing the space requirements of the system. In some variations, the EAP actuator has a heating element to generate heat and, as needed, maintains and controls the humidity and / or temperature and / or direct ambient atmosphere of the EPA actuator. The heating element (s) are resistive and have conductors integrated or adjacent to the EAP film, where the voltage across the conductors is lower than the voltage required for the actuator's activity. Using the same EAP actuator used for lens displacement and / or image stabilization to control the peripheral parameters of the system further reduces the number of components in the system and the overall mass and weight.

33A shows an exemplary EAP actuator 780 available with the lens / optical system of the present invention using a series electrode arrangement for the heating function. The figure shows the high voltage electrode pattern 784 on the ground side of the actuator with the ground electrode pattern 782 and on the other side of the actuator 780 shown in a perspective view. Lugs 786a and 786b respectively establish an electrical connection from the power supply (not shown) of the system to drive the actuator to ground and high voltage inputs. The third protrusion or conductor 786c provides a connection from the power supply for the series resistive heater current path to the low voltage input. Arrows 788 show the annular current path provided by the electrode arrangement using the entire ground electrode 782 as a resistive heating element.

33B shows another EAP actuator using a parallel electrode array for the heating function. The figure shows the ground side of the actuator with the ground electrode pattern 792 and the high voltage pattern 784 shown in perspective from the other side of the actuator. Protrusions 796a and 796b respectively establish electrical connections from the power supply (not shown) of the system for driving the actuator to ground and high voltage inputs. Parallel bus bars 798a and 798b are provided on the ground side of actuator 790 for connection from a power supply (not shown) to each of the ground and low voltage inputs. Arrows 800 show the radial path of current established by the parallel electrode arrangement. Using electrodes in parallel as opposed to the series method allows the use of low power to obtain current flow and induce heating of the film as needed.

As mentioned above, another approach to system humidity and temperature control is to use a resistive heating element disposed adjacent to the EAP actuator. 34 shows a lens displacement mechanism 810 using an EAP actuator with an EAP film 812. The space 816 defined between the upper housing / cover 813 and the EAP film 812 provides enough space for placing the heating element 814. Preferably, the heating body has a profile and size that can be matched to that of the EAP film in order to minimize the space requirements of the system and to maximize the heat transfer between the heating body 814 and the EAP film 812. , Frustum shape as shown in FIG. 34A. The heating body includes a resistive trace 815a on the insulating substrate 815b and the electrical contacts 818 to electrically connect the heating body to the power and sensing electronics of the system.

Another optional feature of the lens displacement systems of the present invention is to provide a sensor for sensing the position of a lens or lens assembly that provides closed-loop control of lens displacement. 35 shows an exemplary embodiment of such a position sensing device associated with lens displacement systems 820 having the same configuration as the lens displacement system of FIG. 7A. The sensing device includes a nested electrode pair having a cylindrical shape. One electrode 822a, for example a ground side electrode, surrounds the outside of the lens barrel 824. Ground electrode 822a is electrically coupled to ground lead 830a through actuator biasing string 830. The other electrode 822b, for example the active or power / sense electrode 822b, surrounds the inner surface of the bushing wall 826 extending upward from the rear end of the housing, with the actuator biasing spring 830 and the lens barrel. It is seated between the outer surface of 824. Electrode 822b is electrically connected to power / sense lead 830b. An insulating material attached to the active electrode 822b is provided in a gap defined between the two electrodes to provide a capacitive structure. Due to the position of the lens barrel as shown, the capacitance across the electrodes is at its maximum. As the lens barrel 824 is placed in the distal direction, the overlapping surface areas of the electrodes increase, which in turn reduces the capacitive charge between them. The charge in the capacitance is fed back to control electronics (not shown) of the system for closed-loop control of the lens position.

With the use of EAP actuators for auto focus, zoom, image stabilization and / or shutter control, such optical lens systems have minimal space and power requirements, and likewise for use in high density optical systems such as mobile phone cameras. For the purpose.

Methods of the present invention in connection with corresponding optical systems, devices, components and components are contemplated. For example, such methods may include selectively focusing a lens on an image, selectively enlarging the image using the lens assembly, and / or selectively moving the image sensor to produce the desired effect generated by the lens or lens assembly. Compensating for the shaking. The methods include the act of providing a suitable device and system in which the subject inventions are used and the conditions can be performed by the last user. In other words, "supply" (e.g., lens, actuator, etc.) simply includes the act of providing the necessary device to the method by the last user's acquisition, access, access, location, setting, activation, operation, or otherwise. do. The methods may include each of the mechanical activations associated with the use of the described apparatus as well as the electrical activation. Likewise, the methodology implied by the use of the described apparatus forms part of the present invention. Moreover, electrical hardware and / or software control and power supplies have influenced the methods of forming part of the present invention.

Another aspect of the invention includes kits having any combination of the devices described herein-whether provided in a packaged combination or assembly by an expert for use operation, instructions for use, and the like. . The kit may comprise any number of optical systems in accordance with the present invention. The kit includes various other components for use with optical systems including mechanical or electrical connections, power supplies, and the like. The kits also include instructions written for the use of the devices or their assemblies. These instructions may be printed on a substrate such as paper or plastic. Similarly, the instructions may be present in the kits as package inserts, in the labeling of the container of the kit or its components (ie associated with the package or server-package). In other embodiments, the instructions are present as an electrical storage data file residing on a suitable computer readable storage medium, eg, a CD-ROM, diskette, or the like. In still other embodiments, the substantial instructions are not present in the kit, but means are provided for obtaining the instructions from a remote source, for example via the Internet. One example of this embodiment is a kit that includes a web address from which instructions can be viewed and / or from which instructions can be downloaded. With the instructions, the means for obtaining the instructions are recorded on a suitable medium.

As for other details of the invention, materials and alternative related shapes may be used within the capabilities of those skilled in the art. The same may support the facts related to the method-based views of the invention in terms of additional acts such as those used generally or logically. In addition, while the present invention has been described with reference to some examples, various features that selectively combine, are described or implied as discussed with reference to each variation of the invention, although the invention is not so limited. Various changes may be made to the described invention, and equivalents (which are cited herein or incorporated for brevity) may be substituted without departing from the spirit and scope of the invention. Any number of individual parts or server-assemblies shown may be incorporated into their design. These changes or others may be undertaken and guided by the principles of design for the assembly.

In addition, it is contemplated that any optional feature of the variations of the invention described may be described and claimed independently or in combination with any one or more features described herein. Referencing a single item includes the possibility that multiple identical items exist. More specifically, singular forms such as “one”, “one”, “above” and “the” as used herein and in the appended claims include plural objects unless otherwise specified. . In other words, the use of articles allows for “at least one” of the subject item in the foregoing description as well as the claims below. It is further noted that the claims may be based on excluding any optional component. Likewise, this statement is intended as a preliminary basis for the use of an exclusionary term such as “alone” or “only” and the citation of claims, or for the use of “negative” limitations. Without the use of such an exclusionary term, the term “comprises” in the claims shall not be construed to contemplate that a given number of elements be listed in the claims or that the addition of features will modify the nature of the elements described in the claims. Nevertheless, the inclusion of any additional element may be allowed. In other words, although not specifically defined herein, all technical and scientific terms used herein will be given the inclusiveness of the meanings as generally understood as possible while maintaining the validity of the claims.

Overall, the scope of the present invention will not be limited by the examples provided.

100: lens module
102: electroactive polymer actuator

Claims (71)

A lens unit including at least one lens disposed along a focal axis and having a linear bearing surface;
An electroactive polymer actuator disposed adjacent said lens and driving to move said lens unit along said focal axis; And
And a linear guide provided adjacent to the linear bearing surface to maintain the position of the lens unit. The method of claim 1,
And a biasing mechanism for biasing the lens unit along the focal axis. The method of claim 2,
The biasing of the lens unit extends the diaphragm of the electroactive polymer actuator into a frustum shape. The method of claim 2,
The biasing mechanism includes a coil spring surrounding the lens unit, and the linear guide is disposed between the coil spring and the outer surface of the lens unit. The method of claim 1,
The linear guide is a bushing wall extending from a housing at least partially surrounding the lens unit. The method of claim 1,
And the linear guide comprises at least one guide rail extending parallel to the focal axis. The method of claim 6,
And the lens unit includes a platform having a hole therein for receiving the at least one guide rail. The method of claim 2,
The biasing mechanism includes a leaf spring mechanism disposed between the lens guide and the outer surface of the lens unit. The method of claim 8,
The leaf spring mechanism has a base ring surrounding the lens unit and a plurality of radially extending tabs fastened to a surface of the electroactive actuator. The method of claim 2,
And the biasing mechanism is integrally formed with the lens unit. The method of claim 10,
The biasing mechanism is further formed integrally with a housing at least partially surrounding the lens unit. The method of claim 2,
The biasing mechanism includes an annular diaphragm extending between the lens unit and the housing, the diaphragm having a negative spring bias. The method of claim 12,
And the diaphragm comprises a low viscosity elastomeric material. The method of claim 2,
The biasing mechanism includes at least two spring tabs extending between the lens unit and the housing. The method of claim 1,
Movement of the lens unit changes the focal length of the lens unit. The method of claim 1,
And the at least one lens is a focus lens. The lens shift system of claim 1, wherein the shift of the lens unit changes the magnification of the lens unit. The method of claim 1,
And the lens unit is moved by a lens driver mechanism that is moved by driving of the actuator. 19. The method of claim 18,
And the lens unit comprises an infinite focus lens assembly. The method of claim 19,
And a plurality of lens stages, each stage including a lens, and wherein the lens driver mechanism moves the plurality of stages at different rates. The method of claim 20,
The ratio of the movement rate of another lens stage to the movement rate of one lens stage defines a telescoping action. The method of claim 20,
Each lens seated in a lens plate moved by the lens driver mechanism. The method of claim 22,
The lens driver mechanism further comprises a pair of connections extending between the lens plates. The method of claim 1,
And a backstop to prevent movement of the lens unit beyond an infinite focal position. The method of claim 1,
And at least one optical filter along the focal axis. The method of claim 1,
And a translucent cover over the front end of the lens unit. The method of claim 1,
The lens unit is configured to calibrate the focus of the lens unit. The method of claim 27,
The housing portion of the lens unit includes at least one groove for receiving a calibration tool. The method of claim 1,
And a sensor for sensing the position of the lens unit. 30. The method of claim 29,
The sensor includes a pair of spaced apart electrodes, a first electrode disposed on an outer side of the lens unit and a second electrode disposed on a surface of the linear guide facing the outer side of the lens unit, The position of the lens unit relative to changes the capacitance across the electrode. The method of claim 1,
And a heating element arranged to control the temperature of at least a portion of the electroactive polymer actuator. The method of claim 1,
The lens unit has a cylindrical barrel structure and the linear bearing surface is an outer surface of the lens barrel. The method of claim 1,
The lens unit includes a plurality of lenses, the distal most lens being a focus lens and the two or more proximal lenses are infinite focus lenses. The method of claim 1,
The electroactive polymer actuator comprises a film configured to bend in only one direction when driven. The method of claim 34,
Said film comprising an elastomeric dielectric layer attached to a backing material, said backplate material having a higher modulus of elasticity than said dielectric layer. A lens unit including at least one lens disposed along a focal axis and biased in an infinity direction within the lens unit;
A back stop to prevent the lens unit from moving beyond the initial macro position in the macro direction; And
And an electroactive polymer actuator disposed adjacent said lens unit and driving to move said lens unit toward said infinite position along said focal axis. A lens unit including at least one lens disposed along a focal axis and movable in opposite directions along the focal axis; And
A two-phase electroactive polymer actuator disposed adjacent the lens unit and driving to move the lens unit along the focal axis and comprising opposing frustum shaped diaphragms biasing each other. Lens shift system. The method of claim 37, wherein
A lens shift system comprising a plurality of two-phase electroactive polymer actuators stacked in series. The method of claim 38,
Adjacent actuators are biased to be spaced apart by a spring. 40. The method of claim 39,
A convex side of the frustum diaphragms facing each other. 41. The method of claim 40,
The convex sides of the frustum diaphragms face each other. A lens unit including at least one lens disposed along a focal axis; And
And an electroactive polymer actuator disposed adjacent to the lens unit and driving to move the lens unit along the focal axis, the electroactive polymer actuator comprising an electroactive polymer film that bends only in one direction when driven. The method of claim 42, wherein
And the film comprises an elastomeric dielectric layer attached to the backplate material, wherein the backplate material has a higher modulus of elasticity than the dielectric layer. The method of claim 42, wherein
The actuator further comprises a fixed base member, wherein the film extends between the lens unit and the base member. The method of claim 44,
The film has an arcuate structure and the backplate material is located on the concave side of the film. The method of claim 44,
And the film has a folded structure. A lens unit including at least one lens disposed along a focal axis; And
And an electroactive polymer actuator disposed adjacent the lens unit and driving to move the lens unit along the focal axis, the electrode arrangement comprising an electrode arrangement configured to generate heat. The method of claim 47,
And the electrode arrangement is configured in series. The method of claim 47,
And the electrode arrangement is configured in parallel. A lens unit including at least one lens disposed along a focal axis;
An electroactive polymer actuator disposed adjacent said lens unit and driving to move said lens unit along said focal axis, said electroactive polymer actuator comprising an electroactive polymer film; And
And a heating element disposed adjacent the electroactive polymer film and having a contour that matches the contour of the electroactive polymer film. 51. The method of claim 50 wherein
And the heating element has a frustum shape. In the apparatus used for the optical system,
At least one aperture blade mounted pivotably; And
An electroactive polymer actuator disposed adjacent said aperture blade,
And said actuator drives said aperture blade to move light through the lens aperture. The method of claim 52, wherein
Apparatus comprising a plurality of cooperative aperture blades arranged in a planar manner. 54. The method of claim 53,
Wherein each aperture blade has a curved teardrop shape, the blades arranged annularly such that at least a portion overlaps an adjacent blade. The method of claim 54,
The actuator includes a two-phase planar film extending between the outer frame member and the inner frame member and the inner frame member has an annular opening through which light passes through the lens aperture, the drive in any one phase being a blade Moving the blade to pivot in one direction and driving in another phase moves the blade to pivot in the opposite direction. The method of claim 52, wherein
And a flexure mechanism that cooperates with the pivoting end of the aperture blade, wherein when driven, the electroactive polymer actuator bends a portion of the flexure mechanism that rotates the aperture blade to pivot. The method of claim 52, wherein
The free end of the aperture blade is provided with a hole through which light passes. A lens unit including at least one lens disposed along a focal axis; And
And two electroactive polymer actuator mechanisms disposed at opposing ends of the lens unit and driving to move the lens unit relative to an actuator. The method of claim 58,
Further comprising at least one guide rail extending between the actuator mechanisms, the lens unit being slidably coupled to the at least one guide rail, the actuator mechanisms being configured such that the lens unit is in a gradual manner along the focal axis. Lens shift system that drives to move. The method of claim 59,
At least one of the actuator mechanisms includes at least two individually driveable portions for moving the at least one guide rail along the focal axis and the transverse direction of the focal axis. The method of claim 60,
Each individually driveable portion comprises an electroactive film layer, the layers being stacked. 62. The method of claim 61,
At least one film layer provides a thickness mode drive when driven and at least one other film layer provides in-plane drive when driven. The method of claim 60,
And the planar drive moves the at least one guide rail angularly. The method of claim 59,
And the lens unit comprises a plurality of lens stages comprising a lens disposed in a platform, wherein at least one lens stage is movable along the focal axis independently of another lens stage. The method of claim 64, wherein
And further comprising a push rod extending between the two actuator mechanisms and driving coupled to the two actuator mechanisms, the push rod passing through the aperture within each lens platform and detachable from the respective lens platform. Combinable Lens Shift System. 66. The method of claim 65,
And a clutch mechanism associated with each lens platform for cooperative engagement with the push rod. The method of claim 58,
Each actuator mechanism includes two individually driveable portions for moving the lens unit along the focal axis and the transverse direction of the focal axis. The method of claim 67,
One drive portion comprises a single-phase linear actuator and the other drive portion includes a two-phase planar actuator successively stacked on each other. The method of claim 68, wherein
And the actuator is independently and selectively controllable to move the push rod in the axial and transverse directions to provide the desired drive sequence. The method of claim 58,
The lens unit includes a focus lens portion and an infinite focus lens portion, wherein a first actuator moves the focus lens portion along the focal axis with respect to the infinite focus lens portion and a second actuator moves the focal lens along the focal axis. Moving the part, the actuator being selectively and independently driveable. The method of claim 70,
And the two lens portions are biased to be spaced apart from each other by a spring.

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