Abstract:
A self-contained means to move a media or component, such as fiber ( 12 ) or other miniature object, such as a lens, into a desired position is given. The fiber ( 12 ) or component is moved in various dimensions to achieve the desired location and is locked into position after the move. An input electrical signal, such as a voltage or current controls movement. A thermal actuator comprises the micro-positioner ( 80 ) using semiconductor technology in one embodiment. In another embodiment, of the present invention, a thermal or electrostatic actuator uses mechanical gears to move the fiber. Another embodiment of the present invention is implemented using mechanical technology such as microelectromechanical system (MEMS) technology. Another embodiment of the present invention, utilizes piezoelectric materials to facilitate fiber movement.

Description:
CROSS REFERENCE TO RELATED APPLICATION  
       [0001]     This application is related to U.S. provisional patent application No. 60/424,741, filed Nov. 8, 2002, entitled IN SITU DYNAMIC FIBER ALIGNER, the entire contents of which are incorporated herein by this reference. The Applicants hereby claim the benefits of this earlier pending provisional application under 35 U.S.C. Section 119(e). 
     
    
     TECHNICAL FIELD  
       [0002]     The present invention relates to one or a plurality of micro-positioners used to dynamically align, position or move media(s), mass(es), or component(s) and device(s) related thereto. Such media include, but are not limited to, one or a plurality of fibers, optical fibers, optical elements, tubes or wires, and such components include, but are not limited to, lenses, nozzles, valves, antenna elements and radio frequency (“rf”) stubs. The micro-positioners can be positioned and secured inside a jacket or other self-contained housing adapted to receive and hold the media or securely hold the components. The micro-positioners may also be used to position materials within an integrated package, such as an optical package.  
       DESCRIPTION OF CONVENTIONAL ART  
       [0003]     The conventional means of aligning a media or component is to statically align the media or component or the mount holding the media or component either passively or actively. Static or statically, refers to the inability to make adjustments to the media after the media and related elements are anchored. To align a media passively, small silicon workbenches are etched into a device using semiconductor technology. Piece parts are then placed upon the etched workbench and secured in place. In the foregoing case, the media could consist of optical fiber. The passive method requires that the optical fiber be precisely located and aligned to a mechanical feature, which can in turn be located in an etched groove within the workbench. The passive method has had limited alignment success because, in many cases, the relationship between the mechanical feature and the optical fiber is not sufficiently precise. Disadvantageously, no adjustment of the optical fiber is possible after placement and anchoring to the final location. The same considerations apply to media other than optical fiber.  
         [0004]     Because of the cited disadvantageous of the passive method, the active method of aligning a media or component is more widely used. The active method uses complex equipment to move a media, typically an optical fiber, into alignment. The equipment then anchors the media, such as an optical fiber, using glue, solder or welding. While the active method is more precise, successful employment of the active method requires complex equipment and precise piece parts with extremely flat and smooth surfaces. Disadvantageously, manufacturing yields using the active method are typically low and rework of the assemblies is difficult. As in the case of passive alignment, active alignment is static. The present invention comprises a dynamic micro-positioner used to position and/or align media or components and includes a variety of embodiments and applications thereof. The present invention can be used to position and/or align a media or components, such media including, but not limited to, one or a plurality of fibers, optical fibers, optical elements, tubes or wires, such components including, but not limited to, lenses and/or nozzles.  
         [0005]     With reference to the conventional art, there are disclosed various conventional active and passive means of and apparatus for aligning media and components, typically optical elements and optical assemblies. The MEMS actuator disclosed in U.S. Pat. No. 6,114,794 to Dhuler et. al., uses a silicon substrate upon which a bimetallic material is added. The method of fabricating the actuator of Dhuler applies a separate heater to expand the bimetallic member. Disadvantageously, the member of Dhuler is securely attached to the substrate such that only a minimum amount of displacement can be achieved. Dhuler further discloses a latch mechanism. However the latch is operable only to lock the optical element in a few discrete positions. In contrast to Dhuler, an embodiment of the present invention includes integral heaters to provide expansion and a locking mechanism to allow for a continuum of possible locked positions. Further, the mechanism of an embodiment of the present invention transitions through a sequence of alternating locking positions. This permits large movements, the integrated heaters providing a user defined step size.  
         [0006]     The apparatus and method of optical switching disclosed in U.S. Pat. No. 6,381,382 B2 to Goodman et. al., adds a composition on the sides of a fiber, longitudinally, which contracts or expands with an electrical signal. The invention of Goodman et. al., is operable to bend fiber and thus align optics. Disadvantageously, the invention of Goodman et. al., requires continuous electrical power to maintain alignment and uses piezoelectric and other materials. Because of local stresses on the fiber, polarization properties of the light signal may be affected. An embodiment of the present invention has integral micro-positioners to move media, such as optical elements, to a desired location. The present invention does not utilize longitudinal actuators attached to fiber, but rather uses a MEMS thermal actuator perpendicular to the fiber.  
         [0007]     The mounting and alignment structure disclosed in U.S. Pat. No. 6,487,355 to Flanders discloses a passive alignment and static anchoring structure fine-tuned by flexion. The invention of Flanders does not permit dynamic anchoring. In contrast, the present invention permits active alignment of a media without flexion and permits dynamic anchoring of the media.  
         [0008]     The fiber optic switching system and method disclosed in U.S. Pat. No. 4,696,062 to LaBudde consists of an optical switch that moves a lens relative to a fixed optical rod between ports to produce a switch wherein alignment is achieved by monitoring a reflection. In contrast, the fiber optic embodiment of the present invention uses free space between two collimators and/or connector or combination of collimator and fiber or connector and fiber.  
         [0009]     The lens assembly disclosed in U.S. Pat. No. 6,374,012 B1 to Bergmann et. al., utilizes a lens within the optical path which, when moved perpendicular to the optical path, causes a change in its pointing angle. The assembly requires external manipulators to move parts to their desired location and incorporates welding, adhesives, or solder to anchor the assembly into position. After anchoring, the elements cannot be further adjusted. In contrast, an embodiment of the present invention utilizes integral micro-positioners to move the elements, such as optical elements, into a desired location. The assembly of the present invention is self-locking in that when power is not supplied, the elements are anchored. Further, the present invention is dynamic in that at any point within the life of the product, power may be applied to move the media, such as a fiber or optical element, to a new setting.  
         [0010]     The piezoelectric apparatus disclosed in U.S. Pat. No. 4,512,036 to Laor uses a piezoelectric component to bend a fiber thus aligning it. With the invention of Laor, if deformation occurs, then the anchoring is static. If not, then voltage must be maintained to secure alignment. The use of piezoelectric, disadvantageously, requires application and maintenance of high voltages to the piezoelectric element. An embodiment of the present invention uses integral micro-positioners to move media, such as optical fiber or optical components, into a desired location. Further, an embodiment of the present invention is self-locking such that when power is not supplied, the media, such as optical fiber or optical components, remain anchored.  
         [0011]     The assembly disclosed in U.S. patent application Ser. No. 09/733,049 by Musk uses silicon machined mechanical parts as a means to locate and move optical elements relative to each other. The assembly requires external manipulators to move parts to a desired location and incorporates welding, adhesives, or glass re-flow to anchor the optical elements into position. Disadvantageously, anchoring is static in that after anchoring the alignment, media or elements cannot receive additional adjustment. An embodiment of the present invention has integral micro-positioners to move the media, such as optical fiber or optical elements, into a desired location. Further, the micro-positioners are self-locking. When power is not supplied to the present invention, the media, such as optical fiber or optical elements, are anchored, yet the present invention remains dynamic in that at any point during the life of the product, power may be applied to move the media to a new setting.  
         [0012]     The method disclosed in U.S. Pat. No. 6,205,266 to Palen uses light coupled from the signal path to provide feedback allowing continuous adjustment of a fiber. This method is referred to as active alignment. The invention of Palen requires continuous power to maintain the position of the optical element. In contrast, an embodiment of the present invention allows periodic alignment, anchoring, and realignment, without the need for continuous power to the micro-positioner. Further, while the invention of Palen covers continuous alignment using optical feedback architecture, it does not include an anchoring mechanism, as does the present invention.  
         [0013]     The apparatus disclosed in U.S. patent application Ser. No. 10/098,742 by Deck et. al., applies interferometric methods to actively align and statically anchor optics using external manipulators. In contrast, an embodiment of the present invention uses internal micro-positioners, dynamic anchoring, and remains transparent to the method used to detect alignment errors.  
         [0014]     None of the following references disclose a method and apparatus for dynamically aligning a media using integral micro-positioners that permit movement of a media, such as an optical fiber or optical element, into a desired location, the micro-positioner assembly being self locking. Further, none of the following disclosed references remain dynamic such that, at any point during the life of the product, power may be applied to implement a new desired setting, such alignment being possible in the field. For example, the method and apparatus disclosed in U.S. Pat. No. 6,244,755 B1 to Joyce et. al., utilizes active alignment and static, not dynamic, anchoring using external manipulators and a metal bracket that is deformed to achieve alignment. The optical interface disclosed in U.S. Pat. No. 6,477,303 to Witherspoon uses V-groove technology to achieve passive alignment and static anchoring to facilitate optical backplanes. The invention of Witherspoon is focused on the optical interface between a circuit board and a main-board using micro-machining techniques to chemically etch paths in the substrate to facilitate self-alignment. The method and apparatus for aligning optical components disclosed in U.S. Pat. No. 6,480,651 B1, to Rabinski uses two stages. One stage is used to align the fiber and the second stage is used to adjust, maintain and lock the optical components about a virtual pivot point. The invention of Rabinski is used to align fiber arrays similar to that used in V-groove technology. The apparatus disclosed in U.S. Pat. No. 6,240,119 to Ventrudo uses a partial reflector and fiber grating in series with an optical beam to stabilize laser performance. The kinematic mount disclosed in U.S. Pat. No. 5,748,827 to Holl et. al., consists of a passive alignment method using a two stage mountable module with a macro-stage and a micro-stage that further includes a fluid flow control channel. The coupling elements disclosed in U.S. Pat. No. 4,452,506 to Reeve et. al., consists of an alignment algorithm and method of using light in a fiber buffer to determine the direction of movement of a fiber needed to achieve alignment. The electrostatic micro-actuator disclosed in U.S. Pat. No. 5,214,727 to Carr et. al., uses an electrostatic actuator for moving a fiber in a switch application. The actuator is specifically designed in an H-shape. The method of Carr et. al., restricts the size of motion and requires large enabling voltages. In contrast, an embodiment of the present invention uses a thermal expansion bar, which provides for both large and small step size movements at low voltages. The alignment apparatus disclosed in U.S. Pat. No. 4,474,423 also uses light in a buffer glass to align fibers for use, for example, in splicing applications. The polarization state changer and phase shifter disclosed in U.S. patent application Ser. No. 10/150,060 by MacDonald utilizes a method whereby stress is applied to a wave-guide to shift phase or modify the polarization state. The method and system for attenuating power in an optical signal disclosed in U.S. patent application Ser. No. 09/796,267 by Cao et. al., utilizes MEMS mirrors in a variable optical attenuator. The structures disclosed in U.S. patent application Ser. No. 10/072,629 by Hsu et. al., provides a means of compensating for thermal effects and stress through flexible symmetry. The apparatus and method disclosed in U.S. patent application Ser. No. 09/775,867 by Miracky uses an electrostatic actuator that moves a lens-using comb drives for the actuator for optical lens movement.  
         [0015]     In “Surface Micro-machined  2 D Lens Scanner Array”, Proc. IEEE/LEOS Optical Mems., by H. Toshiyoshi, G. D. J. Su, J. LaCosse, and M. C. Wu (“Toshiyoshi”), an apparatus that uses a stepping motion to move a lenses into alignment with another optical device is described. Disadvantageously, the apparatus of Toshiyoshi requires significant voltage to move a comb with etched steps in micrometer step increments. An embodiment of the present invention uses integral micro-positioners to move the optical components to a desired location using a thermal expansion bar. The micro-positioner of the present invention can move media, or components, in very small or large steps and can lock the media or component into position when power is not applied. The present invention overcomes the disadvantages of the passive and active alignment methods by providing an inexpensive, dynamic means to align media, such as optical fibers or optical elements, or components. The present invention permits adjustment and alignment of the media or components during subsequent assembly steps and after deployment within a network or apparatus.  
         [0016]     The apparatus disclosed in U.S. Pat. No. 3,902,084 by May discloses a piezoelectric inchworm motor that provides precision motion in one direction. The device does not provide two-dimensional motion, as does the present invention, and is designed to move a cylindrical shaft parallel to piezoelectric actuators. Such a configuration is not suitable in size or orientation to perform the function of an in situ dynamic aligner. In contrast, an embodiment of the present invention uses internal micro-positioners with dynamic anchoring configured for in-situ applications requiring control in a plurality of dimensions.  
         [0017]     The apparatus disclosed in U.S. Pat. No. 6,380,661 by David A. Henderson, also defines a piezoelectric inchworm motor with one dimension operation. The invention uses an interdigitated ridges made using MEMS technology and alternating clamping to make linear movements. To maintain a load electrical power must be applied. The present invention permits movements in a plurality of dimensions, does not require power when holding a load, and provides a small configuration compatible with in-situ applications.  
       BRIEF DESCRIPTION OF THE INVENTION  
       [0018]     The use of fiber optics in telecommunication applications requires the alignment of various optical elements to extremely low tolerances in the range of 0.1 micron. These low tolerances have not previously been encountered in commercial manufacturing. Achieving such low tolerances in alignment of optical fibers and related components requires costly equipment and long manufacturing cycles of optical components. An embodiment of the present invention comprises a component that can achieve low alignment tolerances, while accomplishing optical input/output (“I/O”) objectives. Further, an embodiment of the present invention satisfies a need to dynamically control and tune optical power.  
         [0019]     Critically low tolerances are required between optical fiber lenses or other optical elements such as planer components. These low tolerances are difficult to achieve in volume manufacturing. An embodiment and application of the present invention which comprises an optical aligner and collimator provides a dynamic means to achieve precise, low alignment tolerances and further provides a means to power tune an optical fiber during the life of the component. One embodiment of the present invention comprises a micro-positioner to align and manipulate an optical fiber, the entire assembly adapted to be positioned in a self-contained housing or in an integrated assembly. Depending on the application, a lens and/or jacket, including a hermetic jacket, may be included as part of the self-contained housing. Lenses can be used on the end of the self-contained housing when an application requires beam conditioning. A metal jacket, case, or package can further be used, as necessary to encapsulate the device, facilitate mounting, and/or provide hermetic sealing.  
         [0020]     In one embodiment of the present invention, a micro-positioner moves a media or component, such media including, but not limited to, one or a plurality of fibers, optical fibers, optical elements, tubes or wires, such components including, but not limited to, lenses or nozzles media, in one dimension. In another embodiment of the present invention, a micro-positioner moves a media or component, such media including, but not limited to, one or a plurality of fibers, optical fibers, optical elements, tubes or wires, such components including, but not limited to, lenses or nozzles media, in at least two dimensions in the plane of the micro-positioner.  
         [0021]     An application of the one-dimensional or two-dimensional embodiment of the present invention is as a dynamic collimator. Another application of the one-dimensional or two-dimensional embodiment of the present invention is as a dynamic fiber aligner. A dynamic fiber aligner is similar to a dynamic collimator but the dynamic fiber aligner does not employ a collimating lens. In either of the foregoing applications of the present invention, a dynamic collimator or dynamic fiber aligner is attached to an optical component package by soldering, welding, epoxy or other means. Unlike with conventional collimators or fiber aligning methods, attachment tolerances of the present invention are less critical since the micro-positioner of the present invention is dynamic and may be adjusted electronically to achieve the desired alignment. Active adjustment of the media or component in the present invention is accomplished by applying electrical signals or pulses comprising current through, or a voltage across, micro-positioner arms in certain control sequences to define the direction and distance of the motion of the optic fiber or other media in one or two dimensions. The amplitude or duration of the electrical signals, or pulses, can be used to define the distance traveled. When a signal is not applied, the micro-positioner is locked into position to ensure anchoring at the desired location. An embodiment of the micro-positioner of the present invention is constructed using semiconductor technology. This micro-positioner takes advantage of the measurable thermal expansion characteristics of its expansion bars to cause movement, and hence, positioning and/or alignment, of the media or components. Each expanding, or contracting, expansion bar(s), has a set of corresponding clamps on the ends thereof, and the operation thereof creates a precision stepping motion. At least one expansion bar is required for each degree of freedom desired. Since power dissipated in an expansion bar is proportional to the square of voltage applied, and since thermal expansion is linearly dependent upon power dissipation, expansion or step size is proportional to the square of applied voltage. Thus, the invention has the ability to make large steps, in micrometers, and small steps, in nanometers.  
         [0022]     Several embodiments of the present invention disclosed herein disclose the use of semiconductors to implement the expansion bars, however, the use of thermal expansion bars can be realized using small mechanical parts assembled without using semiconductor technologies. The micro-positioner of the present invention can be implemented using microelectromechanical systems (“MEMS”) technology, where in the micro-positioner, the expansion bar is replaced with silicon etched gears and/or racks. Alternatively, the present invention can be implemented with piezoelectric or other material that expands with application of electrical current or voltage to effect movement. 
     
    
     BRIEF DESCRIPTION OF THE FIGURES  
       [0023]      FIG. 1  illustrates schematically a cross-section of a single channel dynamic collimator wherein the micro-positioner moves an optical fiber.  
         [0024]      FIG. 2  illustrates schematically a cross-section of a single channel dynamic collimator wherein the micro-positioner moves the lens.  
         [0025]      FIG. 3 ( a ) illustrates a side view of a multiple channel dynamic aligner/collimator with N×M channels wherein micro-positioners of the present invention adjust and/or align optical fibers independently.  
         [0026]      FIG. 3 ( b ) illustrates a front view of the N×M array of  FIG. 3 ( a ).  
         [0027]      FIG. 4  illustrates schematically a cross-section of a multiple channel dynamic collimator/aligner with N channels in one direction and M in the other wherein the micro-positioner moves the lenses independently.  
         [0028]      FIG. 5  illustrates the concept of electrical operation of a one dimensional micro-positioner expansion bar.  
         [0029]      FIG. 6  illustrates a pulse train showing typical control signals to the micro-positioner expansion bar for right movement.  
         [0030]      FIG. 7  illustrates a pulse train showing typical control signals to the micro-positioner expansion bar for left movement.  
         [0031]      FIG. 8 ( a ) is a top view of a first embodiment of the micro-positioner assembly of the present invention.  
         [0032]      FIG. 8 ( b ) is an exploded view of a spring, clamp, expansion bar subassembly of the first embodiment of the micro-positioner of the present invention.  
         [0033]      FIG. 9  is a schematic of the electrical operation of a two-dimensional micro-positioner of the present invention.  
         [0034]      FIG. 10  is a top view of a MEMS-based stepping and clamping mechanism for the X-translation stage of a micro-positioner of the present invention.  
         [0035]      FIG. 11  is a top view of a MEMS-based stepping and clamping mechanism for the Y-translation stage of a micro-positioner of the present invention.  
         [0036]      FIG. 12  is a top view of the integrated stepping and clamping mechanism for the X-Y precision translation stages of a micro-positioner of the present invention.  
         [0037]      FIG. 13  is a side view of an integrated stepping and clamping mechanism for the X-Y precision translation stages of a micro-positioner of the present invention.  
         [0038]      FIG. 14  is a top view of a second embodiment of a micro-positioner of the present invention, specifically, a MEMS based mechanism that uses step and clamp motion and slide retainers.  
         [0039]      FIG. 15  illustrates the use of a pair of micro-positioners of the present invention in self-contained housings used to align optical fibers.  
         [0040]      FIG. 16  is a schematic diagram that illustrates the electrical operation of a two dimensional micro-positioner expansion bar.  
         [0041]      FIG. 17  is a logic diagram of the electrical schematic of  FIG. 15 .  
         [0042]      FIGS. 18 and 19  set forth performance and maximum fiber force calculation for an optical fiber embodiment of the present invention.  
         [0043]      FIG. 20  is a graph illustrating range of control, performance as a variable optical attenuator (“VOA”) as a function of fiber displacement.  
         [0044]      FIG. 21 ( a ) is a side view of a lens illustrating a light ray angles from an optical fiber.  
         [0045]      FIG. 21 ( b ) is a graph illustrating optical control and collimator performance as a function of fiber displacement.  
         [0046]      FIG. 22 ( a ) and  22 ( b ) are graphs illustrating constraints on performance of fiber optics. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0047]     An advantage of the present invention is that each media or component, such as an optical fiber or lens, is independently adjustable. When used with optical fiber, the present invention is operable to permit independent optimization of the throughput light. The jacket or other outer housing of the present invention can be constructed using conventional microelectronic and optical packaging technology and standard sizes. The embodiment of the present invention used with optical fiber can be enclosed such that the fiber guide and micro-positioner are positioned in a jacket. Control, or electrical leads pass through apertures in the jacket or housing so that the micro-positioner therein may be adjusted electrically.  
         [0048]     Embodiments of the present invention used in optical fiber applications may also utilize a lens or lens assembly. Lenses are used when beam conditioning of the light is desired. Such embodiments of the present invention maybe enclosed in jackets or housings. In each optical fiber embodiment, a micro-positioner that adjusts the fiber or other media or lens in at least one dimension is required. In optical applications, critical tolerances are required between the optical fiber and lens or, as in the case where lenses are not required, between the optical fiber and other optical elements such as planar components. Optical fibers and fiber guide are enclosed within the jacket or housing using adhesives or other suitable attachment means. The optical fiber embodiments of the present invention can be constructed such that the optical fiber or other media is stationary and the component, such as the lens, is adjusted by the micro-positioner. In such case, the fiber does not pass through the micro-positioner, but the component, such as the lens, is mounted on the micro-positioner. The appearance and size of the jacket or housing enclosing the present invention are similar to collimators or connectors conventionally available, although, as noted, the present invention has control or electrical leads extending through the jacket or housing.  
         [0049]     The micro-positioner is a multi-dimensional device, which, when electrically activated, moves the media or component in steps of variable step size from a few micrometers to a few nanometers in the desired direction. In an embodiment of the present invention, an exposed end of the optical fiber is threaded through a movable mount located on a shuttle subassembly of the micro-positioner. As the movable mount moves in an X-Y direction, the exposed end of the optical fiber bends. The optical fiber sheath proximate to the exposed end of the optical fiber is firmly attached to a fiber guide within the jacket or housing. Distances between the micro-positioner and fiber guide are very large as compared to the micro-positioner movement so that the change in optical fiber to lens distance is not significant and micro-bending losses are not of concern. In operation, a computer algorithm is used to compute and send control signals to the micro-positioner to achieve the desired positioning and/or alignment of the optical fiber. For purposes of this application and the claims herein, reference to movement in the X-Y direction shall be deemed to include movement measured in a polar coordinate system, such as (r, theta) e.g., radius from an origin, and degrees of rotation from an axis.  
         [0050]     The optical fiber embodiment of the present invention is operable to define a collimating light path. Advantageously, the present invention adds no optical elements through which the light must traverse. As such, there is no impact upon optical dispersion or polarization. Implementation of the micro-positioner requires no additional surface area or volume within a conventional collimator package. The device enclosing the micro-positioner appears as a collimator with leads. Employment of the present invention only requires replacement of a conventional collimator or fiber anchor apparatus.  
         [0051]      FIG. 1  illustrates a single channel dynamic collimator  10  embodiment and application of the present invention. As seen therein, the device consists of a conventional buffered fiber that has been stripped of the buffer  11  exposing the optical fiber  12 . The buffered fiber  11  and optical fiber  12  are inserted into fiber guide  13  that aligns the bare optical fiber  12  so it may be inserted into the movable mount of micro-positioner  14 . The micro-positioner  14  is operable to move the optical fiber  12  with precision in two dimensions, Y, which is vertically, and X, which is in and out of the plane of the paper, and lock the optical fiber  12  in place after movement. The buffered fiber  11 , optical fiber  12 , and fiber guide  13  are securely fastened either mechanically, with epoxy, or with other adhesives into the collimator jacket  17  to provide strain relief. A collimating lens  15 , as is required for optical properties, is attached using a hermetic material such as solder and electrical leads  16  are passed through the jacket  17  to permit control or electrical connections to the micro-positioner  14 .  
         [0052]      FIG. 2  also illustrates a single channel dynamic collimator  20  embodiment and application of the present invention, however, the optical fiber  22  is held stationary and the lens  25  is mounted to the micro-positioner  24  to permit positioning and/or alignment. As seen therein, the device consists of a conventional buffered fiber  21  that has been stripped of the buffer exposing the optical fiber  22 . The optical fiber  22  is inserted into a fiber guide  23  that aligns the bare optical fiber  22 . The micro-positioner  24  moves the lens  25  with precision in two dimensions, Y, which is vertically, and X, which is in and out of the plane of the paper, and locks the lens  25  in place after movement. The buffered fiber  21 , optical fiber  22 , and fiber guide  23  are securely fastened either mechanically, with epoxy, or with other adhesives into the collimator jacket  27  to provide strain relief. A collimating lens  25  is attached as is required for optical properties to the micro-positioner  24  and electrical leads  26  are passed through the jacket  27  to permit control or electrical connections to the micro-positioner  24 .  
         [0053]      FIG. 3 ( a ) illustrates a side view of a multiple channel dynamic aligner/collimator with N×M channels wherein micro-positioners of the present invention adjust and/or align the optical fibers. As seen therein, the device consists of a conventional buffered optical fiber ribbon  31  that has been stripped of the buffer exposing a plurality of optical fibers  32 . The optical fibers  32  are inserted into a fiber guide  33  that aligns the bare optical fibers  32  so they may be inserted into the N×M micro-positioners  34 . The micro-positioners  34  can individually move the optical fibers  32  with precision in two dimensions, Y, which is vertically, and X, which is in and out of the plane of the paper, and individually lock the optical fibers  32  or component positions in place after movement. Glass seal  39  may be added to provide a fiber seal. Light exits optical fibers  32  through free space through lens array panel  35 . The buffered optical fiber ribbon  31 , optical fibers  32 , and guide  33  are securely coupled either mechanically or with epoxy  38  into the collimator jacket  37  to provide strain relief. A collimating lens array panel  35  is attached as is required for optical properties and electrical control leads  36  are passed through the jacket  37  to permit electrical connections to the micro-positioner  34 .  
         [0054]      FIG. 3 ( b ) illustrates a front view of an N×M array of  FIG. 3 ( a ). More specifically,  FIG. 3 ( b ) illustrates an 8×8 optical fiber array embodiment of the present invention. As seen therein control leads  36  extend from jacket  37 . Light from the terminating end of each individual optical fiber traverses its correlating lens of lens array panel  35 .  
         [0055]      FIG. 4  shows a multi-optical fiber configuration similar to that of  FIG. 3 , however the embodiment comprises a plurality of collimators arranged in an array and an array of single lenses. As seen therein, the device consists of a conventional buffered optical fiber ribbon  41  that has been stripped of the buffer exposing a plurality of optical fibers  42 . The optical fibers  42  are inserted into optical fiber guide  43  that aligns the bare optical fibers  42 . Each micro-positioner  44  of a N×M micro-positioner array adjusts and/or aligns an individual lens  45  with precision in two dimensions Y, which is vertically, and X, which is in and out of the plane of the paper and individually locks each lens  45  in place after movement. The buffered optical fiber ribbon  41 , optical fibers  42 , and optical fiber guide  43  are securely coupled either mechanically or with epoxy into the collimator jacket  47  to provide strain relief. Each collimating lens  45  is mounted on an individual micro-positioner  44  and electrical leads  46  are passed through the jacket  47  to permit control or electrical connections to each micro-positioner  44  of the N×M micro-positioner array.  
         [0056]      FIG. 5  illustrates the electrical operation of a one-dimensional micro-positioner  50 . As seen therein, when a positive voltage is applied to the direction terminal  56 , the right clamp  53  opens as current flow is determined by diodes  55 . If an additional positive voltage is applied to the axis terminal  57 , then heat is dissipated in the expansion bar  51  by joule heating resulting from current flow in expansion bar  51  or by current flow through resistors (not shown) coupled to expansion bar  51 , results in the expansion bar  51  expanding to the right since clamp  52  is closed. Reversing the voltage on the direction terminal  56  causes the left clamp  52  to open and the right clamp  53  to close. This holds expansion bar  51  to the right as the expansion bar cools. Voltage to direction terminal  56  is removed and both clamps  52  and  53  are closed locking the bar into position. The bar has moved one step in the right direction. Thus, the sequence and polarity of voltage applied to axis terminal  57  and directional terminal  56  of  FIG. 5 , in the manner shown in  FIG. 6 , will result in the movement of the expansion bar  51  of  FIG. 5  to the right. The sequence and polarity of voltages applied to axis terminal  57  and directional terminal  56  of  FIG. 5 , in the manner shown in  FIG. 7  will result in the movement of expansion bar  51  of  FIG. 5  to the left.  
         [0057]     Clamps  52  and  53  of  FIG. 5  used to hold the expansion bar can also be thermally activated. When no voltage is applied, the clamp, a conductive band, fits tight over the expansion bar. This clamping function can be achieved with various implementations. When voltage is applied to the clamp, the clamp expands and releases the expansion bar. Each time the voltage cycles the expansion bar steps in the direction defined by the direction voltage polarity. The size of the step is proportional to the square of the axis voltage applied as seen in Equation 1 below. Thus, the micro-positioner will make large steps for high voltages and small or fine adjustments for low voltages. This allows for minimum alignment times as well as fine resolution. As can be seen from Equation 1, the constant of proportionality is a function of material properties and configuation.  
                   S   =     α   ⁢           ⁢   L   ⁢     θ   R     ⁢     V   2                   S   =     step   ⁢           ⁢   for   ⁢           ⁢   each   ⁢           ⁢   voltage   ⁢           ⁢   pulse                 α   =     Coefficient   ⁢           ⁢   of   ⁢           ⁢   thermal   ⁢           ⁢   expansion                 L   =     Length   ⁢           ⁢   of   ⁢           ⁢   actuator   ⁢           ⁢     (     Clamp   ⁢           ⁢   to   ⁢           ⁢   Clamp     )                   θ   =     Thermal   ⁢           ⁢   resistance                 R   =     Electrical   ⁢           ⁢   resistance                 V   =     Applied   ⁢           ⁢   Voltage                   Equation   ⁢           ⁢   1   ⁢     -     ⁢   Step   ⁢           ⁢   Size             
 
         [0058]     In operation, the expansion bar must be allowed to heat and cool. The time constant for these transisitons is given in Equation 2 below In practice the bar will cool faster than equation 2 predicts, since equation 2 considers thermal conductivity only when in practice, thermal convection will also occur.  
                   Time   ⁢           ⁢   Constants               λ   =     θ   ⁢           ⁢     dC   t     ⁢   LWT                 λ   =     Time   ⁢           ⁢   constant                   C   t     =     Specific   ⁢           ⁢   Heat                 d   =   Density               W   =     Width   ⁢           ⁢   of   ⁢           ⁢   expansion   ⁢           ⁢   bar                 L   =     Length   ⁢           ⁢   of   ⁢           ⁢   expansion   ⁢           ⁢   bar                 T   =     Thickness   ⁢           ⁢   of   ⁢           ⁢   expansion   ⁢           ⁢   bar                 θ   =     Thermal   ⁢           ⁢   Resistance                   Equation   ⁢           ⁢   2             
 
         [0059]     Equations 1 and 2 predict the step length versus voltage and time. Thus, expansion bar motion may be defined as follows for the heating cycle and for the cooling cycle as follows: 
 
 During Heating:  
         S   H     =     α   ⁢           ⁢     L   ⁡     (       V   2     ρ     )       ⁢     (     1   K     )     ⁢     (     1   -     ⅇ     -     t   λ           )           
 
 During Cooling  
         S   C     =       S   H     ⁡     (     ⅇ     -     t   λ         )           
 
         [0060]     Where the symbols are as above in Equations 1 and 2 and S H  is heating step size, S C  is cooling step size, K is thermal conductivity and ρ is electrical resistivity.  
         [0061]     Employing an expansion bar in two dimensions requires two expansion bars but adds the complication that each expansion bar must have two degrees of freedom. One degree of freedom is needed to accomplish controlled movement and the second is needed to allow free movement in the orthogonal direction.  
         [0062]      FIG. 8 ( a ) is a top view of a first embodiment of the micro-positioner  80  of the present invention. As seen therein, micro-positioner  80  is comprised of the following subassemblies, components and elements: shuttle  81 , shuttle springs  82 , x-axis expansion bars  83 ( a ) and  83 ( b ), x-axis bond pads  84 ( a ) and  84 ( b ), x-axis clamps  85 ( a ) and  85 ( b ), x-axis expansion springs  86 ( a ) and  86 ( b ), y-axis expansion bars  87 ( a ) and  87 ( b ), y-axis bond pads  88 ( a ) and  88 ( b ), y-axis clamps  89 ( a ) and  89 ( b ), y-axis expansion springs  810 ( a ) and  810 ( b ), movable mount  811 , and movable mount aperature  812 . In one embodiment of the present invention, the foregoing components and elements are comprised of semiconductor material. The shuttle  81  of micro-positioner  80  is adapted to move in the X direction. Shuttle  81  is attached to micropositioner  80  with eight shuttle springs  82  and the shuttle  81  is adjusted or aligned in the X direction by two expansion subassemblies  FIG. 8 ( b ). Within shuttle  81  are two expansion subassemblies, one for movement in the positive Y direction and one for movement in the negative Y direction. The X direction expansion subassembly consists of x-axis expansion bars  83 ( a ) and  83 ( b ), two sets of thermal actuated x-axis clamps  85 ( a ) and  85 ( b ) and two sets of x-axis expansion springs  86 ( a ) and  86 ( b ). The Y direction expansion subassembly consists of y-axis expansion bars  87 ( a ) and  87 ( b ), two sets of thermal actuated y-axis clamps  89 ( a ) and  89 ( b ) and two sets of y-axis expansion springs  810 ( a ) and  810 ( b ). Associated with each expansion assembly are a set of bond pads to which electrical connections can be made to the expansion bars and clamps. In the X direction, these comprise bond pads  84 ( a ) and  84 ( b ) and in the Y direction these comprise bond pads  88 ( a ) and  88 ( b ). External analog or logic circuitry (not shown) are coupled to micro-positioner  80  via these bond pads.  
         [0063]     The micro-positioner  80  can be manufactured as a silicon chip and can be implemented in one or two-dimensional arrays. Alternating the clamping and unclamping of directional clamps as associated expansion bars are powered by the drive stepping motion.  
         [0064]      FIG. 8 ( b ) is an exploded view of x-axis expansion assembly consisting of springs  86 ( b ), x-axis clamps  85 ( b ), legs  851 ( b ) of x-axis clamps  85 ( b ), and x-axis expansion bars  83 ( b ) of the micro-positioner  80  of  FIG. 8 ( a ). The other x-axis expansion subassembly and the y-axis subassemblies are substantively similar to the subassembly of  FIG. 8 ( a ), except for their directional orientation. In operation, a voltage differential is introduced across bond pads  84 ( a ). This causes a current to flow through leg  851 ( b ) and leg  852 ( b ) of x-axis clamp  85 ( b ). Due to the size difference in the two legs, leg  852 ( b ) has more resistance than leg  851 ( b ), causing leg  852 ( b ) to heat up more and thus expand. This in turn causes the x-axis clamp  85 ( b ) to bend and open up. This effect is characteristic of any homogeneous material such as silicon of which the x-axis clamp  85 ( b ) is made. Pressure between the clamp  85 ( b ) and the outer edge of x-axis expansion bars  83 ( b ) disengage when x-axis clamp  85 ( b ) bends outward. Similar effects can be caused by introducing voltage potentials at the bond pads of the other expansion subassemblies of micro-positioner  80 . Referring back to  FIG. 8 ( a ), when current flows through x-axis clamp  85 ( b ) it opens while x-axis clamp  85 ( a ), without current, is closed. Simultaneously, current can be introduced through x-axis expansion bars  83 ( a ) to cause them to expand, thus moving the shuttle assembly  81  to the left. Soon thereafter, current flow is stopped through x-axis clamp  85 ( b ) whereby x-axis clamp  85 ( b ) cools and retracts to its original position. Clamp  85 ( b ) applies pressure to the outer edge of x-axis expansion bars  83 ( b ) re-engaging and locking the x-axis expansion bars into place once x-axis clamp  85 ( b ) has cooled. Clamp  85 ( a ) is opened as is claim  85 ( b ) and the current through expansion bar  83 ( a ) is stopped. After expansion bar  83 ( a ) cools, current to clamp  85 ( b ) is removed and the shuttle  81  is locked into place. Similar operation and timing of this procedure on x-axis clamps  85 ( a ),  85 ( b ) and x-axis expansion bars  83 ( b ) causes movement of shuttle  81  to the right. Operation and timing of this procedure on y-axis clamps  89 ( a ), and  89 ( b ) and y-axis expansion bars  87 ( a ) and  87 ( b ) causes movement of movable mount  811  downward. Operation and timing of this procedure on y-axis clamp  89 ( b ),  89 ( a ) and y-axis expansion bars  87 ( b ) causes movement of movable mount  811  upward. When a terminated end of a media is threaded through aperture  812  and secured to movable mount  811 , the movement of shuttle  81  and or movable mount  811  moves the terminated end of the optical fiber.  
         [0065]      FIG. 9  is a schematic of the electrical operation of the two-dimensional micro-positioner of the present invention. As seen therein, by controlling polarity and sequence of input voltages  99  and  90 , the direction and axis of motion are determined. By controlling voltage amplitude of  90 , step size is determined and the number of voltage pulse determines distance moved. If a positive voltage is applied at  99 , current flows through Y-up  91  and X-right  92  to ground  98 . In other words, current is directed through the up clamps and the right clamps, so those clamps open up. If, then a positive voltage is applied at  90 , current flows through the X-axis expansion bar  93  and causes movement along the X right direction. If a negative voltage is applied at  90 , current flows through the Y-axis expansion bar  94  and causes movement in the Y-up direction. After expansion, the voltage is reversed at  99  so that the appropriate clamps close or open to prevent movement after removal of voltage at  90  and cooling of the expansion bar. When the expansion bar cools, all voltages are removed to lock the axis in place. Similar operation, with reverse sequence at terminal  99  and negative voltage applied at terminal  90 , will provide motion of the y-axis down and with  90  positive, x-axis movement in the left direction occurs.  
         [0066]     Another embodiment of the present invention uses heaters attached to the expansion bar to cause the adjustment of the micro-positioner. The step size is controlled by the thermal expansion, heater to the expansion bar increases the types of material that can be used as the expansion bar. For an example, titanium carbide can be used as it has expansion and thermal conductivity advantages over other types of materials. Tantalum nitride resistor elements can be used to provide heat. This combination provides similar step size control and significantly increases micro-positioner speed.  
         [0067]     FIGS.  10  to  13  illustrate the micro-positioner of the present invention also implemented using MEMS technology. This implementation illustrated in FIGS.  10  to  13  uses differential expansion thermal actuators that are conventionally known in the art to perform the precision translation, through the scanning mechanism, and the precision clamping, through the clamping mechanism. Specifically,  FIG. 10  shows a layout of the MEMS-based clamping X-translation stage.  FIG. 11  shows a layout for a MEMS-based clamping Y-translation stage.  FIG. 12  shows the X-translation stage mounted to the Y-translation stage to form the assembly for a X-Y translation stage.  FIG. 13  shows the cross section of the X-Y stage assembly.  
         [0068]     Micro-positioner  100  is shown in  FIG. 10 . As seen in  FIG. 10 , by controllably applying electrical signals through electrical connections to the bond pads  101 , the direction and magnitude of scan by scanning mechanism  102  can be controlled in steps for gross positioning or in sub-step distances for fine positioning. This is accomplished by moving the scanner bar  103  to engage the gears with the gears on the scanning mechanism, deflecting the scanner bar  103  in the direction of desired scan, then disengaging the scanner bar  103 . Also by controlling the electrical signal applied to the clamp mechanism  104 , the clamp can be released for X stage motion and reengaged to hold the X scanning mechanism in a fixed position. The clamp mechanism  104  is used to hold the translation stage in place whenever it is not being moved by the scanning mechanism  102 . The retainers  105  are sleeves that are over-the-edge clamps that restrain the motion of the translating component in one direction while allowing it to move freely in the other. The retainers  105  are not physically attached to the translation stages or the clamp mechanisms, but there is a small space between the retainers and the translation stage. Thermal actuators  106  perform translation through scanning mechanism  102  and precision clamping through clamp mechanism  104 . Voltage is varied on the expansion actuators to set the step size. Motions less than a gear step can be made. While gears are shown on the scanning mechanism  102  in  FIG. 10  as the means of moving and then locking the scanner bar  103 , they may be removed for finer resolution.  
         [0069]      FIG. 11  illustrates a micro-positioner  110  of the present invention that is adapted as a Y translation stage. As seen therein, movable mount aperture  112  of movable mount  111  is moved in the Y direction by scanning mechanism  113  through the expansion and contraction of the geared scanner bar  114 , opening and closing of clamp mechanism  115  and retainers  116 . Thermal actuators described earlier in the discussion of  FIG. 8 ( b ) move the scanner bar. While gears are shown in  FIG. 11  as the means of moving and then locking the movable mount  111 , they may be removed and replaced by friction contacts for finer resolution.  
         [0070]      FIG. 12  is a top view of the integrated clamping mechanism  120  for the X-Y precision translation stages of the micro-positioner of the present invention. As seen in  FIG. 12 , the X-translation stage  100  and the Y-translation stage  110  are fabricated separately and the X-translation stage is physically attached to the Y-translation stage using standard techniques such as epoxy bonding, atomic bonding, solder reflow, eutectic bonding, or others. Standard silicon-based MEMS fabrication techniques may be used for the fabrication among other methods. For example, standard silicon-on-silicon and/or multi-level fabrication may be used to create the multilevel structure. The fiber relief cavity can be formed using deep reactive ion etching, among other techniques. Other methods of micro-positioner fabrication such as micro machining and LIGA fabricated parts would also provide a multi-dimensional device that when properly electrically activated will step the fiber to the desired position.  
         [0071]      FIG. 13  is a side view of an integrated clamping mechanism  120  for the X-Y precision translation stages of the micro-positioner of the present invention. As seen therein, X stage  100  is mounted or formed on x-stage substrate  134 , which is mounted on Y stage  110 . The terminated end of a media, such as optical fiber  132 , is threaded through fiber relief cavity  133  of Y stage substrate  131 . Retainers  135  hold the various assemblies and subassemblies of micro-positioner  120  in position. The stages may be retained by other means, such as springs.  
         [0072]      FIG. 14  is a top view of a second embodiment of the micro-positioner  140  of the present invention. As seen therein, micro-positioner  140  is comprised of the following subassemblies, components and elements: pinion actuators  141 ( a ) and  141 ( b ), pinion drives  142 ( a ) and  142 ( b ), pinion release  143 ( a ) and  143 ( b ), axis hold actuator  144 ( a ) and  144 ( b ), x-axis and y-axis interconnection bond pads  145 ( a ) and  145 ( b ), x-axis slides and y-axis slides  146 ( a ) and  146 ( b ), axis setup actuators  147 ( a ) and  147 ( b ), and a movable aperture  148 .  
         [0073]     The apparatus of  FIG. 14  provides for both X and Y motion without using retention springs as seen in the first embodiment of the micro-positioner. The moving aperture  148  slides and is guided by x-axis slides and y-axis slides  146 ( a ) and  146 ( b ). The pinions  141 ( a ) and  141 ( b ), provide motion as follows: at rest all pinion actuators,  142 ( a ),  142 ( b ),  143 ( a ),  143 ( b ),  144 ( a ) and  144 ( b ) are in contact with and are clamping movable aperture  148  such that the movable aperture is locked into position. When movement is desired, for example, in the X-direction, a voltage is applied to holding actuators  144 ( a ) which expand and release the aperture  148 . An additional voltage is applied to pinion drive actuators  142 ( a ) which expand and push the aperture to the left. After the movement, voltage is removed from holding actuators  144 ( a ) and they contract clamping the aperture. Voltage is then applied to pinion release actuator  143 ( a ), which expands and releases the movable aperture, whereupon voltage can be removed from the pinion drive  142 ( a ), and the pinion  141 ( a ) moves back to its rest position. Voltage is then removed from pinion release  143 ( a ), and the pinion contracts back to clamp the movable aperture. One step is completed. Additional application of the above voltage sequence causes the movable aperture to continue stepping to the left. Right movement is similar except the sequence of voltage application is reversed. In operation, the pin release  143 ( a ) is actuated moving it from movable aperture  148 , the pinion drive  142 ( a ) is actuated moving it to the left, voltage is removed for the pinion release  143 ( a ) and the pinion clamps movable aperture  148 , voltage is applied to the pinion hold  144 ( a ) releasing movable aperture  148 , voltage is removed from the pinion drive and movable aperture  148  is pulled to the right, voltage is removed from the pinion release  143 ( a ) and movable aperture  148  is in its rest state. Additional application of this voltage sequence causes the movable aperture ( 148 ) to move in steps to the right. Movement in the y-direction is achieved by performing the operation and timing of this procedure on Y-axis actuators  142 ( b ),  143 ( b ), and  144 ( b ) which moves movable aperture  148  downward or upward.  
         [0074]     Prior to using micro-positioner  140 , it may need to be set up. The setup is required for devices that are fabricated using chemical etching procedures. Machining by etching creates gaps between features. As in the case for actuators  143 ( a ),  143 ( b ),  144 ( a ), and  144 ( b ), these gaps prevent firm clamping in the rest case with no voltages applied. The expansion mechanism  147 ( a ) and  147 ( b ) are provided to achieve setup. Expansion mechanism  147 ( a ) and  147 ( b ) consist of four arms, two wide for low electrical resistance and two narrow for much greater electrical resistance, all electrically connected such that when voltage is applied at the corresponding bond pads, current flows through all four arms. Appling voltage to expansion mechanisms  147 ( a ) or  147 ( b ), results in the narrow arm heating and expanding more than the wide arm and the expansion mechanism  147 ( a ) or  147 ( b ) bow. When the expansion mechanism  147 ( a ) and  147 ( b ) bow, they physically contract and move slides  146 ( a ) and  146 ( b ). Slides  146 ( a ) and  146 ( b ) are then moved to place actuators  144 ( a ),  144 ( b ),  143 ( a ), and  143 ( b ) into firm contact with movable aperture  148 . Removing the voltage from  147 ( a ) and or  147 ( b ) results in the assemblies contracting and moving back to their rest position, but since the assemblies are not physically connected to the slides  146 ( a ) and  146 ( b ), the actuators  144 ( a ),  144 ( b ),  143 ( a ), and  143 ( b ) remain in firm contact.  
         [0075]     The micro-positioner  140  can be manufactured as a silicon chip and can be implemented in one or two dimensions. A sequence of voltage or current pulse applied to the bond pads of the mechanism drives stepping motion in the desired direction.  
         [0076]      FIG. 15  illustrates one use of aligner  151  and aligner  152  of the present invention to achieve alignment of light paths through optical components  153 . Optical components  153  are housed in case  154 . An in situ dynamic aligner application and embodiment of the present invention utilizing the micro-positioner  80  of  FIG. 8 ( a ), is illustrated wherein aligner  151  is inserted into case  154  at the optical input and aligner  152  is inserted into case  154  at the output. Applying voltages at the leads  156  of aligners  151  and  152  adjust the terminated ends of optical fibers  157  and thus adjust the optical path  155  of a light beam to a desired position.  
         [0077]      FIG. 16  is a schematic diagram that illustrates the electrical operation of a two-dimensional micro-positioner  160 . The clamp/expansion bar expansion and contraction operation of the X-Y micro-positioner  160  is similar to that of the one-dimensional micro-positioner  50  of  FIG. 5 . As seen in  FIG. 16 , when a positive voltage is applied to axis terminal  161 , X movement is enabled and when a negative voltage is applied to axis terminal  162 , Y movement is enabled. When a positive voltage is applied to direction terminal  162 , the X-axis direction is to the right or the Y-axis direction is up and when a negative voltage is applied to direction terminal  162  the X-axis direction is to the left or the Y-axis direction is down.  FIG. 17  is a logic diagram of the electrical schematic of  FIG. 16 .  
         [0078]      FIGS. 18 and 19  set forth optical performance and maximum fiber force required for an exemplary embodiment of the present invention.  
         [0079]      FIG. 18  lists the governing equations relating change in beam pointing angle and lateral displacement as the media, such as an optical fiber, is displaced by a micro-positioner, where b is defined as the fiber displacement, d the beam displacement and φ o  is the beam-pointing angle. The equations apply for conventional lenses although gradient index and spherical lenses among others may be used.  
         [0080]     The formulas of  FIG. 19  represent a media, such as an optical fiber, treated as a cantilever beam. One end of an optical fiber is attached and held rigid. The other, terminated end is fitted with the micro-positioner of the present invention that positions and adjusts the optical fiber. That causes a slight arc into the optical fiber, thus a certain amount of force is required to hold it in position. In box  1  of  FIG. 18 , W represents the formula for the force required to hold the optical fiber in position, I is the moment of inertia, a is the length of the optical fiber from the point it is in contact with the micro-positioner to the point where it is held or the length to the cantilever beam. Box  2  of  FIG. 18  is the formula for I, the moment of inertia, where r is the radius of the optical fiber. The formulas of box  1  and  2  lead to the equation of box  3 , which is the equation that describes the forces necessary to hold the optical fiber in position using the representative parameters of box  4 . As seen in  FIG. 18 , the micro-positioner must exert a force of approximately 2.0 milli-newton to hold an optical fiber in place.  
         [0081]      FIG. 20  is a graph illustrating performance of a VOA, with range of control as a function of fiber displacement. As seen therein, when an optical fiber is moved to one side, insertion loss takes place, and thus the device is acting as an attenuator. In operation, typically there are two such devices, thus, there would be twice the attenuation performance.  
         [0082]      FIG. 21 ( a ) is a side view of a lens illustrating light ray output pointing angles and output beam displacement as the fiber is displaced radially.  FIG. 21 ( b ) is a graph illustrating optical control and collimator performance as a function of fiber displacement. As seen therein,  FIG. 21 ( b ) illustrates several optical results of moving an optical fiber using the present invention. These include a change in the pointing angle, the working distance between the optical fiber and lens, and the offset of the beam at the output of the lens. In  FIG. 21 ( b ), the working distance is shown as a line with boxes. Advantageously, working distance changes very little as the optical fiber is displaced. The pointing angle refers to when the light leaves the lens. It is shown as a line with diamonds on  FIG. 21 ( b ). It changes over a range as much as five degrees of point and angle changes. Beam displacement, shown as a line with circles, advantageously tracks substantially linearly as it changes up to about  700  microns.  
         [0083]      FIG. 22 ( a ) and  22 ( b ) are graphs illustrating typical mechanical constraints on design and manufacturing of the in situ fiber aligner embodiment and application of the present invention. These constraints apply to typical applications but they may be violated as an application may require.  
         [0084]     Advantages of the present invention include (i) substantial cost reduction and improved performance; (ii) during application no human intervention and no specialized equipment are required. The small form factor of the present invention allows several devices per semiconductor wafer in the semiconductor embodiment of the present invention. The present invention is remotely configurable, can be utilized in active and passive network components and meets industry requirements for maintaining alignment during mechanical and thermal stresses.  
         [0085]     A variety of components can be manipulated by the micropositioner arrangement. These include lenses, prisms, detectors, diodes, laser diodes, sensors, antenna elements, rf stubs, valves or nozzles. The optical embodiment of the present invention can be used in any device requiring an optical interface, such as variable optical attenuators (“VOAs”), demultiplexers, multiplexers, switches, optical amplifiers, filters, transmitters, receivers, modulators and for gain flattening or tilting.  
         [0086]     The innovative teachings of the present invention are described with particular reference to the embodiments disclosed herein. However, it should be understood and appreciated by those skilled in the art that the several embodiments of the apparatus disclosed herein provide only examples of the many advantageous uses and innovative teachings herein. Various non-substantive alterations, modifications and substitutions can be made to the disclosed apparatus without departing in any way from the spirit and scope of the invention.