MEMS Deformable Lens Assembly and Process Flow

A glass membrane deformation assembly configured to deform a glass membrane includes: a deformable glass membrane having a first surface and a second surface; a piezoelectric layer affixed to a first surface of the deformable glass membrane, wherein the piezoelectric layer is controllably deformable via a voltage potential; a structural member affixed to at least a first portion of the second surface of the deformable glass membrane; and a deformable lens assembly affixed to at least a second portion of the second surface of the deformable glass membrane; wherein the controllably deformation of the piezoelectric layer is configured to controllably deform the deformable glass membrane and the deformable lens assembly.

TECHNICAL FIELD

This disclosure relates to actuators in general and, more particularly, to miniaturized MEMS actuators configured for use within camera packages and methods of making the same.

BACKGROUND

As is known in the art, actuators may be used to convert electronic signals into mechanical motion. In many applications such as e.g., portable devices, imaging-related devices, telecommunications components, and medical instruments, it may be beneficial for miniature actuators to fit within the small size, low power, and cost constraints of these application.

Micro-electrical-mechanical system (MEMS) technology is the technology that in its most general form may be defined as miniaturized mechanical and electro-mechanical elements that are made using the techniques of microfabrication. The critical dimensions of MEMS devices may vary from well below one micron to several millimeters. In general, MEMS actuators are more compact than conventional actuators, and they consume less power.

SUMMARY OF DISCLOSURE

In one implementation, a glass membrane deformation assembly configured to deform a glass membrane includes: a deformable glass membrane having a first surface and a second surface; a piezoelectric layer affixed to a surface of the deformable glass membrane, wherein the piezoelectric layer is controllably deformable via a voltage potential; a structural member affixed to at least a first portion of the second surface of the deformable glass membrane; and a deformable lens assembly affixed to at least a second portion of the second surface of the deformable glass membrane; wherein the controllably deformation of the piezoelectric layer configured to controllably deform the deformable glass membrane and the deformable lens assembly.

One or more of the following features may be included. The piezoelectric layer may be configured to controllably deform the deformable glass membrane from a generally planar configuration to a generally convex configuration. The deformable glass membrane may be a circular deformable glass membrane. The piezoelectric layer may be a ring-shaped piezoelectric layer. The piezoelectric layer may be affixed to the surface of the deformable glass membrane via a sputtering technique. The piezoelectric layer may include a first electrode and a second electrode applying the voltage potential. The structural member may be a ring-shaped structural member. The structural member may include one or more of: a metal-based structural member; and a silicon-based structural member. The structural member may be affixed to the second surface of the deformable glass membrane via one or more of: an epoxy; and a bonding technique. The deformable glass membrane may be a quartz-based deformable glass membrane. The deformable lens assembly may be a polymer deformable lens assembly. The deformable lens assembly may include a rigid pillar assembly. A rigid base structure may be affixed to the deformable lens assembly.

In another implementation, a glass membrane deformation assembly configured to deform a glass membrane includes: a deformable glass membrane having a first surface and a second surface; a piezoelectric layer affixed to a surface of the deformable glass membrane, wherein the piezoelectric layer is controllably deformable via a voltage potential; a structural member affixed to at least a first portion of the second surface of the deformable glass membrane; and a deformable lens assembly affixed to at least a second portion of the second surface of the deformable glass membrane; wherein; the controllably deformation of the piezoelectric layer is configured to controllably deform the deformable glass membrane and the deformable lens assembly, the deformable glass membrane is a circular deformable glass membrane, and the piezoelectric layer is a ring-shaped piezoelectric layer.

One or more of the following features may be included. The piezoelectric layer may be configured to controllably deform the deformable glass membrane from a generally planar configuration to a generally convex configuration. The piezoelectric layer may include a first electrode and a second electrode for applying the voltage potential. The structural member may be a ring-shaped structural member. The structural member may include one or more of: a metal-based structural member; and a silicon-based structural member. The deformable glass membrane may be a quartz-based deformable glass membrane. The deformable lens assembly may be a polymer deformable lens assembly. The deformable lens assembly may include a rigid pillar assembly. A rigid base structure may be affixed to the deformable lens assembly.

In another implementation, a method of producing a glass membrane deformation assembly includes: partially fabricating a glass membrane deformation assembly using MEMS process; affixing the glass membrane deformation assembly onto a silicon substrate; inverting the glass membrane deformation assembly; and dispensing a polymer into a cavity section of the glass membrane deformation assembly.

One or more of the following features may be included. A rigid pillar assembly may be installed within the polymer. A rigid base structure may be affixed to the glass membrane deformation assembly. The glass membrane deformation assembly may be cured. Partially fabricating a glass membrane deformation assembly using MEMS process may include: affixing a piezoelectric layer to a surface of a deformable glass membrane; etching a portion of the piezoelectric layer to expose a portion of the surface of the deformable glass membrane; affixing a structural member to a second surface of the deformable glass membrane; and etching a portion of the structural member to expose a portion of the second surface of the deformable glass membrane. Affixing a piezoelectric layer to a surface of a deformable glass membrane may include: sputtering the piezoelectric layer to the surface of the deformable glass membrane. Affixing a structural member to a second surface of the deformable glass membrane may include: affixing the structural member to the second surface of the deformable glass membrane via an epoxy. Affixing a structural member to a second surface of the deformable glass membrane may include; bonding the structural member to the second surface of the deformable glass membrane via a bonding technique.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring toFIG.1, there is shown MEMS package10, in accordance with various aspects of this disclosure. In this example, MEMS package10is shown to include printed circuit board12, multi-axis MEMS assembly14, driver circuits16, electronic components18, flexible circuit20, and electrical connector22. Multi-axis MEMS assembly14may include micro-electrical-mechanical system (MEMS) actuator24(configured to provide linear three-axis movement) and optoelectronic device26coupled to micro-electrical-mechanical system (MEMS) actuator24.

As will be discussed below in greater detail examples of micro-electrical-mechanical system (MEMS) actuator24may include but are not limited to an in-plane MEMS actuator, an out-of-plane MEMS actuator, and a combination in-plane/out-of-plane MEMS actuator. For example and if micro-electrical-mechanical system (MEMS) actuator24is an in-plane MEMS actuator, the in-plane MEMS actuator may include an electrostatic comb drive actuation system (as will be discussed below in greater detail). Additionally, micro-electrical-mechanical system (MEMS) actuator24is an out-of-plane MEMS actuator, the out-of-plane MEMS actuator may include a piezoelectric actuation system or electrostatic actuation. And if micro-electrical-mechanical system (MEMS) actuator24is a hybrid in-plane/out-of-plane MEMS actuator, the combination in-plane/out-of-plane MEMS actuator may include an electrostatic comb drive actuation system and a piezoelectric actuation system.

As will be discussed below in greater detail, examples of optoelectronic device26may include but are not limited to an image sensor, a holder assembly, an IR filter and/or a lens assembly. Examples of electronic components18may include but are not limited. to various electronic or semiconductor components and devices. Flexible circuit20and/or connector22may be configured to electrically couple MEMS package10to e.g., a smart phone or a digital camera (represented as generic item28).

In some embodiments, some of the components of MEMS package10may be joined together using various epoxies/adhesives. For example, an outer frame of micro-electrical-mechanical system (MEMS) actuator24may include contact pads that may correspond to similar contact pads on printed circuit board12.

Referring also toFIG.2A, there is shown multi-axis MEMS assembly14, which may include optoelectronic device26coupled to micro-electrical-mechanical system (MEMS) actuator24. As discussed above, examples of micro-electrical-mechanical system (MEMS) actuator24may include but are not limited to an in-plane MEMS actuator, an out-of-plane MEMS actuator, and a combination in-plane/out-of-plane MEMS actuator.

Referring also toFIG.2B, plurality of electrically conductive flexures32of micro-electrical-mechanical system (MEMS) actuator24may be curved upward and buckled to achieve the desired level of flexibility & compression. In the illustrated embodiment, plurality of electrically conductive flexures32may have one end attached to MEMS actuation core34(e.g., the moving portion of micro-electrical-mechanical system (MEMS) actuator24) and the other end attached to outer frame30(e.g., the fixed portion of micro-electrical-mechanical system (MEMS) actuator24).

Plurality of electrically conductive flexures32may be conductive wires that may extend above the plane (e.g., an upper surface) of micro-electrical-mechanical system (MEMS) actuator24and may electrically couple laterally separated components of micro-electrical-mechanical system (MEMS) actuator24. For example, plurality of electrically conductive flexures32may provide electrical signals from optoelectronic device26and/or MEMS actuation core34to outer frame30of micro-electrical-mechanical system (MEMS) actuator24. As discussed above, outer frame30of micro-electrical-mechanical system (MEMS) actuator24may be affixed to circuit board12using epoxy (or various other adhesive materials or devices).

Referring also toFIG.3, there is shown a top view of micro-electrical-mechanical system (MEMS) actuator24in accordance with various embodiments of the disclosure. Outer frame30is shown to include (in this example) four frame assemblies (e.g., frame assembly100A, frame assembly100B, frame assembly100C, frame assembly100D) that are shown as being spaced apart to allow for additional detail.

Outer frame30of micro-electrical-mechanical system (MEMS) actuator24may include a plurality of contact pads (e.g., contact pads102A on frame assembly100A, contact pads102B on frame assembly100B, contact pads102C on frame assembly100C, and contact pads102D on frame assembly100D), which may be electrically coupled to one end of plurality of electrically conductive flexures32. The curved shape of electrically conductive flexures32is provided for illustrative purposes only and, while illustrating one possible embodiment, other configurations are possible and are considered to be within the scope of this disclosure.

MEMS actuation core34may include a plurality of contact pads (e.g., contact pads104A, contact pads104B, contact pads104C, contact pads104D), which may be electrically coupled to the other end of plurality of electrically conductive flexures32. A portion of the contact pads (e.g., contact pads104A, contact pads104B, contact pads104C, contact pads104D) of MEMS actuation core34may be electrically coupled to optoelectronic device26by wire bonding, silver paste, or eutectic seal, thus allowing for the electrical coupling of optoelectronic device26to outer frame30.

Electrostatic Actuation

MEMS actuation core34may include one or more comb drive sectors (e.g., comb drive sector106) that are actuation sectors disposed within micro-electrical-mechanical system (MEMS) actuator24. The comb drive sectors (e.g., comb drive sector106) within MEMS actuation core34may be disposed in the same plane and may be positioned orthogonal to each other to allow for movement in two axes (e.g., the X-axis and the Y-axis). Accordingly, the in-plane MEMS actuator generally (and MEMS actuation core34specifically) may be configured to provide linear X-axis movement and linear Y-axis movement.

While in this particular example, MEMS actuation core34is shown to include four comb drive sectors, this is for illustrative purposes only and is not intended to be a limitation of this disclosure, as other configurations are possible. For example, the number of comb drive sectors may be increased or decreased depending upon design criteria.

While in this particular example, the four comb drive sectors are shown to be generally square in shape, this is for illustrative purposes only and is not intended to be a limitation of this disclosure, as other configurations are possible. For example, the shape of the comb drive sectors may be changed to meet various design criteria.

While the comb drive sectors (e.g., comb drive sector106) within MEMS actuation core34are shown to be positioned orthogonal to each other to allow for movement in two axes (e.g., the X-axis and the Y-axis), this is for illustrative purposes only and is not intended to be a limitation of this disclosure, as other configurations are possible. For example, the comb drive sectors (e.g., comb drive sector106) within MEMS actuation core34may be positioned parallel to each other to allow for movement in a single axis (e.g., either the X-axis or the Y-axis).

Each comb drive sector (e.g., comb drive sector106) within MEMS actuation core34may include one or more moving portions and one or more fixed portions. As will be discussed below in greater detail, a comb drive sector (e.g., comb drive sector106) within MEMS actuation core34may be coupled, via a cantilever assembly (e.g., cantilever assembly108), to outer periphery110of MEMS actuation. core34(i.e., the portion of MEMS actuation core34that includes contact pads104A, contact pads104B, contact pads104C, contact pads104D), which is the portion of MEMS actuation core34to Which optoelectronic device26may be coupled thus effectuating the transfer of movement to optoelectronic device26.

Referring also toFIG.4, there is shown a top view of comb drive sector106in accordance with various embodiments of the present disclosure. Each comb drive sector (e.g., comb drive sector106) may include one or more motion control cantilever assemblies (e.g., motion control cantilever assemblies150A,150B) positioned outside of comb drive sector106, moveable frame152, moveable spines154, fixed frame156, fixed spines158, and cantilever assembly108that is configured to couple moving frame152to outer periphery110of MEMS actuation core34. In this particular configuration, motion control cantilever assemblies150A,150B may be configured to prevent Y-axis displacement between moving frame152/moveable spines154and fixed frame156/fixed spines158.

Comb drive sector106may include a movable member including moveable frame152and multiple moveable spines154that are generally orthogonal to moveable frame152. Comb drive sector106may also include a fixed member including fixed frame156and multiple fixed spines158that are generally orthogonal to fixed frame156. Cantilever assembly108may be deformable in one direction (e.g., in response to Y-axis deflective loads) and rigid in another direction (e.g., in response to X-axis tension and compression loads), thus allowing for cantilever assembly108to absorb motion in the Y-axis but transfer motion in the X-axis.

Referring also toFIG.5, there is shown a detail view of portion160of comb drive sector106. Moveable spines154A,154B may include a plurality of discrete moveable actuation fingers that are generally orthogonally-attached to moveable spines154A,154B. For example, moveable spine154A is shown to include moveable actuation fingers162A and moveable spine154B is shown to include moveable actuation lingers162B.

Further, fixed spine158may include a plurality of discrete fixed actuation lingers that are generally orthogonally-attached to fixed spine158. For example, fixed spine158is shown to include fixed actuation fingers164A that are configured to mesh and interact with moveable actuation fingers162A. Further, fixed spine158is shown to include fixed actuation fingers164B that are configured to mesh and interact with moveable actuation fingers162B.

Accordingly, various numbers of actuation fingers may be associated with (i.e., coupled to) the moveable spines (e.g., moveable spines154A,154B) and/or the fixed spines (e.g., fixed spine158) of comb drive sector106. As discussed above, each comb drive sector (e.g., comb drive sector106) may include two motion control cantilever assemblies150A,150B separately placed on each side of comb drive sector106. Each of the two motion control cantilever assemblies150A,150B may be configured to couple moveable frame152and fixed frame156, as this configuration enables moveable actuation fingers162A,162B to be displaceable in the X-axis with respect to fixed actuation fingers164A,164B (respectively) while presenting moveable actuation fingers162A,162B from being displaced in the Y-axis and contacting fixed actuation fingers164A,164B (respectively).

While actuation fingers162A,162B,164A,164B (or at least the center axes of actuation fingers162A,162B,164A,164B) are shown to be generally parallel to one another and generally orthogonal to the respective spines to which they are coupled, this is for illustrative purposes only and is not intended to be a limitation of this disclosure, as other configurations are possible. Further and in some embodiments, actuation fingers162A,162B,164A,164B may have the same width throughout their length and in other embodiments, actuation fingers162A,162B,164A,164B may be tapered.

Further and in some embodiments, moveable frame152may be displaced in the positive X-axis direction when a voltage potential is applied between actuation fingers162A and actuation fingers164A, while moveable frame152may be displaced in the negative X-axis direction when a voltage potential is applied between actuation fingers162B and actuation fingers164B.

Referring also toFIG.6, there is shown a detail view of portion200of comb drive sector106. Fixed spine158may be generally parallel to moveable spine154B, wherein actuation fingers164B and actuation fingers162B may overlap within region202, wherein the width of overlap region202is typically in the range of 10-50 microns. While overlap region202is described as being in the range of 10-50 microns, this is for illustrative purposes only and is not intended to be a limitation of this disclosure, as other configurations are possible.

Overlap region202may represent the distance204where the ends of actuation fingers162B extends past and overlap the ends of actuation fingers164B, which are interposed therebetween. In some embodiments, actuation fingers162B and actuation fingers164B may be tapered such that their respective tips are narrower than their respective bases (i.e., where they are attached to their spines). As is known in the art, various degrees of taper may be utilized with respect to actuation fingers162B and actuation lingers164B. Additionally, the overlap of actuation fingers162B and actuation fingers164B provided by overlap region202may help ensure that there is sufficient initial actuation force when an electrical voltage potential is applied so that MEMS actuation core34may move gradually and smoothly without any sudden jumps when varying the applied voltage. The height of actuation fingers162B and actuation fingers164B may be determined by various aspects of the MEMS fabrication process and various design criteria.

Length206of actuation fingers162B and actuation fingers164B, the size of overlap region202, the gaps between adjacent actuation fingers, and actuation finger taper angles that are incorporated into various embodiments may be determined by various design criteria, application considerations, and manufacturability considerations, wherein these measurements may be optimized to achieve the required displacement utilizing the available voltage potential.

As shown inFIG.3and as discussed above, MEMS actuation core34may include one or more comb drive sectors (e.g., comb drive sector106), wherein the comb drive sectors (e.g., comb drive sector106) within MEMS actuation core34may be disposed in the same plane and may be positioned orthogonal to each other to allow for movement in two axes (e.g., the X-axis and the Y-axis).

Specifically and in this particular example, MEMS actuation core34is shown to include four comb drive sectors (e.g., comb drive sectors106,250,252,254). As discussed above, comb drive sector106is configured to allow for movement along the X-axis, while preventing movement along the Y-axis. As comb drive sector252is similarly configured, comb drive sector252may allow for movement along the X-axis, while preventing movement along the Y-axis. Accordingly, if a signal is applied to comb drive sector106that provides for positive X-axis movement, while a signal is applied to comb drive sector252that provides for negative X-axis movement, actuation core34may be displaced in a clockwise direction. Conversely, if a signal is applied to comb drive sector106that provides for negative X-axis movement, while a signal is applied to comb drive sector252that provides for positive X-axis movement, actuation core34may be displaced in a counterclockwise direction.

Further, comb drive sectors250,254are configured (in this example) to be orthogonal to comb drive sectors106,252. Accordingly, comb drive sectors250,254may be configured to allow for movement along the Y-axis, while preventing movement along the X-axis. Accordingly, if a signal is applied to comb drive sector250that provides for positive Y-axis movement, while a signal is applied to comb drive sector254that provides for negative Y-axis movement, actuation core34may be displaced in a counterclockwise direction. Conversely, if a signal is applied to comb drive sector250that provides for negative Y-axis movement, while a signal is applied to comb drive sector254that provides for positive Y-axis movement, actuation core34may be displaced in a clockwise direction.

Accordingly, the in-plane MEMS actuator generally (and MEMS actuation core34specifically) may be configured to provide rotational (e.g., clockwise or counterclockwise) Z-axis movement

As staled above, examples of micro-electrical-mechanical system (MEMS) actuator24may include but are not limited to an in-plane MEMS actuator, an out-of-plane MEMS actuator, and a combination in-plane/out-of-plane MEMS actuator. For example and referring also toFIGS.7A-7C, micro-electrical-mechanical system (MEMS) actuator24is shown to include an in-plane MEMS actuator (e.g., in-plane MEMS actuator256) and an out-of-plane MEMS actuator (e.g., out-of-plane MEMS actuator258), whereinFIGS.3-6illustrate one possible embodiment of in-plane MEMS actuator256. Optoelectronic device26may be coupled to in-plane MEMS actuator256; and in-plane MEMS actuator256may be coupled to out-of-plane MEMS actuator258.

An example of in-plane MEMS actuator256may include but is not limited to an image stabilization actuator. As is known in the art, image stabilization is a family of techniques that reduce blurring associated with the motion of a camera or other imaging device during exposure. Generally, it compensates for pan and tilt (angular movement, equivalent to yaw and pitch) of the imaging device, though electronic image stabilization may also compensate for rotation. Image stabilization may be used in image-stabilized binoculars, still and video cameras, astronomical telescopes, and smartphones. With still cameras, camera shake may be a particular problem at slow shutter speeds or with long focal length (telephoto or zoom) lenses. With video cameras, camera shake may cause visible frame-to-frame jitter in the recorded video. In astronomy, the problem may be amplified by variations in the atmosphere (which changes the apparent positions of objects over time).

An example of out*of-plane MEMS actuator258may include but is not limited to an autofocus actuator. As is known in the art, an autofocus system may use a sensor, a control system and an actuator to locus on an automatically (or manually) selected area. Autofocus methodologies may be distinguished by their type (e.g., active, passive or hybrid). Autofocus systems may rely on one or more sensors to determine correct focus, wherein some autofocus systems may rely on a single sensor while others may use an array of sensors.

FIGS.7A-7Cshow one possible embodiment of out-of-plane MEMS actuator258in various states of activation/excitation. Out-of-plane MEMS actuator258may include frame260(which is configured to be stationary) and moveable stage262, wherein out-of-plane MEMS actuator258may be configured to provide linear Z-axis movement. For example, out-of-plane MEMS actuator258may include a multi-morph piezoelectric actuator that may be selectively and controllably deformable when an electrical charge is applied, wherein the polarity of the applied electrical charge may vary the direction in which the multi-morph piezoelectric actuator (i.e., out-of-plane MEMS actuator258) is deformed. For example,FIG.7Ashows out-of-plane MEMS actuator258in a natural position without an electrical charge being applied. Further,FIG.7Bshows out-of-plane MEMS actuator258in an extended position (i.e., displaced in the direction of arrow264) with an electrical charge having a first polarity being applied, whileFIG.7Cshows out-of-plane MEMS actuator258in a retracted position (i.e., displaced in the direction of arrow266) with an electrical charge having an opposite polarity being applied.

As discussed above, the multi-morph piezoelectric actuator (i.e., out-of-plane MEMS actuator258) may be deformable by applying an electrical charge. In order to accomplish such deformability that allows for such linear Z-axis movement, the multi-morph piezoelectric actuator (i.e., out-of-plane MEMS actuator258) may include a bending piezoelectric actuator.

As discussed above, the multi-morph piezoelectric actuator (i.e., out-of-plane MEMS actuator258) may include rigid frame assembly260(which is configured to be stationary) and moveable stage262that may be configured to be affixed to in-plane MEMS actuator256. As discussed above, optoelectronic device26may be coupled to in-plane MEMS actuator256and in-plane MEMS actuator256may be coupled to out-of-plane MEMS actuator258. Accordingly and when out-of-plane MEMS actuator258is in an extended position (i.e., displaced in the direction of arrow264) with an electrical charge having a first polarity being applied (as shown inFIG.7B), optoelectronic device26may be displaced in the positive z-axis direction and towards a leas assembly (e.g., lens assembly300,FIG.8). Alternatively and when out-of-plane MEMS actuator258is in a retracted position (i.e., displaced in the direction of arrow266) with an electrical charge having an opposite polarity being applied (as shown inFIG.7C), optoelectronic device26may be displaced in the negative z-axis direction and away from a lens assembly (e.g., lens assembly300,FIG.8). Accordingly and by displacing optoelectronic device26in the z-axis with respect to a lens assembly (e.g., lens assembly300,FIG.8), autofocus functionality may be achieved.

The multi-morph piezoelectric actuator (i.e., out-of-plane MEMS actuator258) may include at least one deformable piezoelectric portion (e.g., deformable piezoelectric portions268,270,272,274) configured to couple moveable stage262to rigid frame assembly260.

For example and in one particular embodiment, multi-morph piezoelectric actuator (i.e., out-of-plane MEMS actuator258) may include a rigid intermediate stage (e.g., rigid intermediate stages276,278). A first deformable piezoelectric portion (e.g., deformable piezoelectric portions268,270) may be configured to couple rigid intermediate stage (e.g., rigid intermediate gages276,278) to moveable stage262; and a second deformable piezoelectric portion (e.g. deformable piezoelectric portions272,274) may be configured to couple the rigid intermediate stage (e.g., rigid intermediate stages276,278) to rigid frame assembly260.

Linear Z-axis (i.e., out-of-plane) movement of moveable stage262of out-of-plane MEMS actuator258may be generated due to the deformation of the deformable piezoelectric. portion (e.g., deformable piezoelectric portions268,270,274), which may be formed of a piezoelectric material (e.g., PZT (lead zirconate titanate), zinc oxide or other suitable material) that may be configured deflect in response to an electrical signal. As is known in the art, piezoelectric materials are a special type of ceramic that expands or contracts when an electrical field is applied thus generating motion and force.

While out-of-plane MEMS actuator258is described above as including a single moveable stage (e.g., moveable stage262) that enables linear movement in the Z-axis, this is for illustrative purposes only and is not intended to be a limitation of this disclosure, as other configurations are possible and are considered to be within the scope of this disclosure. For example, out-of-plane MEMS actuator258may be configured to include multiple moveable stages. For example, if deformable piezoelectric portions272,274were configured to be separately controllable, additional degrees of freedom (such as tip and/or tilt) may be achievable. For example and in such a configuration displacing intermediate stage276in an upward direction (i.e., in the direction of arrow264) While displacing intermediate stage278in a downward direction (i.e., in the direction of arrow266) would result in clockwise rotation of optoelectronic device26about the Y-axis; while displacing intermediate stage276in a downward direction (i.e., in the direction of arrow266) while displacing intermediate stage278in a upward direction (i.e., in the direction of arrow264) would result in counterclockwise rotation of optoelectronic device26about the Y-axis. Additionally/alternatively, corresponding clockwise and counterclockwise rotation of optoelectronic device26about the X-axis may be achieved via additional/alternative intermediate stages.

WhileFIGS.7A-7Ceach show one possible embodiment of an out-of-plane piezoelectric MEMS actuator in various states of activation/excitation, this is for illustrative purposes only and is not intended to be a limitation of this disclosure, as other configurations are possible and are considered to be within the scope of this disclosure. For example and as shown inFIG.7D, in-plane piezoelectric MEMS actuator280may be formed in a fashion similar to that of the above-described in-plane electrostatic MEMS actuators. Accordingly, in-plane piezoelectric MEMS actuator280may include a plurality of piezoelectric drive sectors (e.g., piezoelectric drive sectors282,284,286,288) configured in a similar orthogonal fashion (e.g., piezoelectric drive sectors282,286being configured to enable movement in one axis and piezoelectric drive sectors284,288being configured to enable movement in an orthogonal axis), thus enabling movement in the X-axis and the Y-axis, and rotation about the Z-axis.

Glass Membrane Deformation Assembly:

As discussed above, optoelectronic device26may be coupled to in-plane MEMS actuator256and in-plane MEMS actuator256may be coupled to out-of-plane MEMS actuator258. Accordingly and when out-of-plane MEMS actuator258is in an extended position (i.e., displaced in the direction of arrow264) with an electrical charge having a first polarity being applied (as shown inFIG.7B). optoelectronic device26may be displaced in the positive z-axis direction and towards a lens assembly (e.g., lens assembly300,FIG.8). Alternatively and when out-of-plane MEMS actuator258is in a retracted position (i.e., displaced in the direction of arrow266) with an electrical charge having an opposite polarity being applied (as shown inFIG.7C), optoelectronic device26may be displaced in the negative z-axis direction and away from a lens assembly (e.g., lens assembly300,FIG.8). Accordingly and by displacing optoelectronic device26in the z-axis with respect to a lens assembly (e.g., lens assembly300,FIG.8), autofocus/zoom functionality may be achieved.

Referring also toFIG.9A, micro-electrical-mechanical system (MEMS) actuator24and/or ♦lens assembly300may include a glass membrane deformation assembly (e.g., glass membrane deformation. assembly350) configured to perform such autofocus functionality. In one exemplary embodiment, glass membrane deformation assembly350may be positioned between optoelectronic device26and lens assembly300. In another embodiment, glass membrane deformation assembly350may replace one of the lenses within lens assembly300, and may be configured to vary the focal length of lens assembly300, thus effectuating such autofocus functionality.

Referring also toFIGS.9B-9D, glass membrane deformation assembly350may be configured to deform a glass membrane. Accordingly, glass membrane deformation assembly350may include a deformable glass membrane (e.g., deformable glass membrane352) having a first surface (e.g., first surface354) and a second surface (e.g., second surface356). An example of the deformable glass membrane (e.g., deformable glass membrane352) may include but is not limited to a quartz-based deformable glass membrane.

A piezoelectric layer (e.g., piezoelectric layer358) may be affixed to a surface (e.g., first surface354or second surface356) of the deformable glass membrane (e.g., deformable glass membrane352). This piezoelectric layer (e.g., piezoelectric layer358) may be controllably deformable via a voltage potential (e.g., from voltage source360). An example of voltage source360may include but is not limited to a DC (i.e., direct current) voltage source configured to provide a DC voltage of sufficient strength (e.g., upwards of 200 volts DC) to effectuate the desired level of deformation of the deformable glass membrane (e.g., deformable glass membrane352). The piezoelectric layer (e.g., piezoelectric layer358) may include a first electrode (e.g., first electrode362) and a second electrode (e.g., second electrode364) for applying the voltage potential (e.g., from voltage source360).

An example of the piezoelectric layer (e.g., piezoelectric layer358) may include but is not limited to a multi-morph piezoelectric layer that may be selectively and controllably deformable when an electrical charge is applied (e.g., from voltage source360), wherein the polarity of the applied electrical charge (e.g., from voltage source360) may vary the direction in which the multi-morph piezoelectric layer (e.g., piezoelectric layer358) is deformed.

The piezoelectric layer (e.g., piezoelectric layer358) may be affixed to the surface (e.g., first surface354or second surface356) of the deformable glass membrane (e.g., deformable glass membrane352) via a sputtering technique or any other physical vapor deposition (PVD) technique. As is known in the art, sputtering is a phenomenon in which microscopic particles of a solid material are ejected from its surface after the material is itself bombarded by energetic particles of a plasma or gas.

A structural member (e.g., structural member366) may be affixed to at least a first portion of the second surface (e.g., second surface356) of tire deformable glass membrane (e.g., deformable glass membrane352). The controllable deformation of the piezoelectric layer (e.g., piezoelectric layer358) may be configured to controllably deform the deformable glass membrane (e.g., deformable glass membrane352).

The structural member (e.g., structural member366) may include one or more of: a metal-based structural member (e.g., a nickel structural member or a stainless-steel structural member) and a silicon-based structural member. The structural member (e.g., structural member366) may be affixed to the second surface of the deformable glass membrane (e.g., deformable glass membrane352) via an epoxy (or various other adhesives/materials) and/or via a bonding technique (e.g., applying structural member366at a specific temperature so that it adheres to deformable glass membrane352).

In a preferred embodiment, an example of the deformable glass membrane (e.g., deformable glass membrane352) may include but is not limited to a circular deformable glass membrane; an example of the piezoelectric layer (e.g., piezoelectric layer358) may include but is not limited to a ring-shaped piezoelectric layer; and an example of the structural member (e.g., structured member366) may include but is not limited to a ring-shaped structural member.

Glass membrane deformation assembly350may include a deformable lens assembly (e.g., deformable lens assembly368) affixed to at least a second portion of the second surface (e.g., second surface356) of the deformable glass membrane (e.g., deformable glass membrane352). Being deformable lens assembly368is affixed to deformable glass membrane352, any controlled deformation of piezoelectric layer358(which is also affixed to deformable glass membrane352) may also controllably deform deformable lens assembly368.

The deformable lens assembly (e.g., deformable lens assembly368) may be a polymer deformable lens assembly, An example of such a polymer may include any optically clear polymer, As will be discussed below in great detail, by deforming the shape of deformable lens assembly368, the focal length of deformable lens assembly368may be changed to e.g., effectuate such autofocus functionality.

The deformable lens assembly (e.g., deformable lens assembly368) may include a rigid pillar assembly (e.g., rigid pillar as370). Examples of rigid pillar assembly370may include a rigid pillar assembly constructed of a higher modulus polymer (when compared to the rest of deformable lens assembly368) or a piece of optically clear glass or plastic.

A rigid base structure (e.g., rigid. base structure372) may be affixed to the deformable lens assembly (e.g., deformable lens assembly368). An example of the rigid base structure (e.g., rigid base structure372) may include but is not limited to a quartz based glass rigid base structure.

Deformable glass membrane352may be processed to make deformable glass membrane352more easily deformed. For example, one or more grooves may be etched into deformable glass membrane352in the illustrative pattern shown inFIG.10.

Generally speaking, the piezoelectric layer (e.g., piezoelectric layer358) may be configured to controllably deform the deformable glass membrane (e.g., deformable glass membrane352) from a generally planar configuration (as shown inFIGS.11A-11B) to a generally convex configuration (as shown inFIG.12A-12B) to e.g., effectuate such autofocus functionality.

For example and for illustrative purposes:FIGS.11A-11Billustrates glass membrane deformation assembly350when no voltage potential is applied to first electrode362and second electrode364of the piezoelectric layer (e.g., piezoelectric layer358), resulting in deformable glass membrane352being essential planar.FIGS.12A-12Billustrates glass membrane deformation assembly350when a voltage potential (e.g., from voltage source360) having a forward polarity is applied to first electrode362and second electrode364of the piezoelectric layer (e.g., piezoelectric layer358). The application of such a forward polarity voltage potential may result in a deformation of piezoelectric layer358, resulting in a downward force at inflection point374and an upward convexity of deformable glass membrane352(in the positive Z axis) due to the rigidity of rigid pillar assembly370. Conversely, the application of a reverse polarity voltage potential to first electrode362and second electrode364of piezoelectric layer358may result in a deformation of piezoelectric layer358, resulting in an upward force at inflection point374and a downward convexity of deformable glass membrane352(in the negative Z axis) due to the rigidity of rigid pillar assembly370.

Referring also toFIG.13, there is shown a method (e.g., method400) of producing glass membrane deformation assembly350. Method400may utilize a standard thickness piece of glass as the starting point for producing glass membrane deformation assembly350. As discussed above, an example of such a standard thickness piece of glass may include but is not limited to a quartz-based piece of glass, as shown inFIG.14A.

When affixing404a piezoelectric layer (e.g., piezoelectric layer358) to a surface (e.g., first surface354or second surface356) of deformable glass membrane352, method400may sputter406the piezoelectric layer (e.g., piezoelectric layer358) onto the surface (e.g., first surface354or second surface356) of deformable glass membrane352. As discussed above, sputtering is a phenomenon in which microscopic particles of a solid material are ejected from its surface after the material is itself bombarded by energetic particles of a plasma or gas. Partially fabricating402glass membrane deformation assembly350may etching408a portion of the piezoelectric layer (e.g., piezoelectric layer358) to expose a portion of the surface (e.g., first surface354or second surface356) of deformable glass membrane352,352), as shown inFIG.12C

Method400for producing glass membrane deformation assembly350may include affixing418glass membrane deformation assembly350onto a silicon substrate and inverting420glass membrane deformation assembly350. For example, method400may mount glass membrane deformation assembly350(thus far) upside down on a tape assembly, as shown inFIG.12D. Once inverted, method400may thin the deformable glass membrane (e.g., deformable glass membrane352) to a desired thickness. An example of such a desired thickness for deformable glass membrane352may include but is not limited to 20-200 micrometers.

Partially fabricating402glass membrane deformation assembly350may include affixing410a structural member (e.g., structural member366) to a second surface (e.g., second surface356) of deformable glass membrane352, as shown inFIG12E. As discussed above, an example of the structural member (e.g., structural member366) may include one or more of: a metal-based structural member (e.g., a nickel structural member or a stainless-steel structural member) and a silicon-based structural member.

When affixing410a structural member (e.g., structural member366) to a second surface (e.g., second surface356) of the deformable glass membrane (e.g., deformable glass membrane352), method400may:affix412the structural member (e.g., structural member366) to the second surface (e.g., second surface356) of the deformable glass membrane (e.g., deformable glass membrane352) via an epoxy; and/orbond414the structural member (e.g., structural member366) to the second surface (e.g., second surface356) of the deformable glass membrane (e.g., deformable glass membrane352) via a bonding technique.

Partially fabricating402glass membrane deformation assembly350may include etching416a portion of the structural member (e.g., structural member366) to expose a portion of the second surface (e.g., second surface356) of deformable glass membrane352. Specifically, by etching408a portion of piezoelectric layer358to expose a portion of first surface354or second surface356of deformable glass membrane352and etching416a portion of structural member366to expose a portion of second surface356of deformable glass membrane352, deformable glass membrane352may allow for the passage of light.

Method400for producing glass membrane deformation assembly350may include dispensing422a polymer into a cavity section. of glass membrane deformation assembly350(e.g., to form deformable lens assembly368), as shown inFIG.14F.

Method400for producing glass membrane deformation assembly350may include installing424a rigid pillar assembly (e.g., rigid pillar assembly370) within the polymer (e.g., that formed deformable lens assembly368) and affixing426a rigid base structure (e.g., rigid base structure372) to glass membrane deformation assembly350, as shown inFIG.14G. Method400for producing glass membrane deformation assembly350may include curing428glass membrane deformation assembly350.

In general, the various operations of method described herein may be accomplished using or may pertain to components or features of the various systems and/or apparatus with their respective components and subcomponents, described herein.