Self-balancing comb drive for out-of-plane actuation

Abstract

Disclosed is a MEMS device that has comb drives and flexures that generate out-of-plane motion. The comb drive includes a two set of stationary comb banks that are anchored on one or more sides. These stationary comb banks are interdigitated with another two set of moveable comb fingers that is anchored on a backplane in opposite directions. The backplane is offset from an anchor with in-line flexures to allow the movable comb to rotate about the anchor. The stationary combs are vertically offset from the movable fingers and generate out of plane motion when voltage is applied.

Description

[0001] SELF-BALANCING COMB DRIVE FOR OUT-OF-PLANE ACTUATION

[0002] TECHNICAL FIELD:

[0003] The present invention directs towards to the field of microelectromechanical systems (MEMS) manufacturing. More specifically, the present invention directs towards to MEMS devices that have comb drives and flexures that generate an out-of-plane motion.

[0004] BACKGROUND:

[0005] The MEMS (Micro-Electro-Mechanical Systems) micro-mirror has wide applications such as, display, scanning, or LiDAR applications. In a display application, MEMS mirror-based system is often referred to laser beam steering (LBS) system where the laser beam is steered by one or multiple micro mirrors to general patterned illumination or moving and still images. MEMS micro mirrors are also widely used in fiber optics communication to make optical filter or optical channel monitor device (OCM) where a MEMS micro mirror is used to steer an amplitude, frequency, or phase modulated wideband light across a diffraction grating and splits the wavelength in free space and into an optical detector to monitor or manipulate the carrying signal. In both shared application examples, a large mirror with large scanning angle within a small footprint is often desirable for various technical and commercial reasons. However, there is often many drawbacks when implementing these desirable features to the MEMS mirror. For example, increasing mirror size results in increasing in overall mass and necessities in strengthening torsional flexure to maintain the same scanning speed. Moreover, increasing the stiffness of the flexure increases the stresses on the structure as deforms happens during device actuation, it is very challenging to build a high-speed mirror with large scanning / tilting angle. On the other hand, it is also highly desirable to increase surface area of the comb finger to result in larger capacitance for generating larger electrostatic force. It is often difficult to increase capacitance in the comb drive without causing stability issue or increasing the die size to accommodate more fingers. The presented invention addresses many of these challenges and making a quasi-static MEMS micro-mirror with large reflector feasible to have smaller overall footprint and lower actuation voltage.

[0006] Figure 1 shows a micro mirror 20 of the prior art, specifically a predecessor of micro-mirror disclosed herewith. Micro-mirror 20 is a one axis tilting mirror which moves out-of-plane and tilts in both positive and negative directions. There are two movable comb drives 201 and 206. Movable comb drive 201 is on the left side of mirror body 202, and movable comb drive 206 is on the right of mirror body 202. Both are interdigitated and vertically offset from the stationary comb drives 203 and 204 which are anchored from base onto the substrate. The movable finger on movable comb drive 201 are anchored to the backplane 207 and joining the mirror body 202. The movable structures 201 , 207, 202 are suspended and anchored to the base substrate via flexible flexure 205. The flexible 205 is uniquely designed to withstand the lateral force component that is partially generated by the comb drive while generating rotating motion on the mirror.

[0007] This structure does not allow for large mirror or large displacements. There remains a need for a improved micro mirror.

[0008] SUMMARY:

[0009] According to an aspect, a construction of self-balancing comb drive for high tilting micro mirror is disclosed. Electrostatic comb drives are often deployed in a MEMS device to sense or generate planer motion of a proof mass to make device like accelerometer, gyroscope, resonator etc. Another common application for electrostatic comb drives is optical mirror, where the micro mirror may be resonant or quasi-static. For resonant MEMS mirror, the inplane comb drive can be used to generate torque on the mirror and causing it to scan at a constant angular velocity and exhibit the benefit the of mechanical amplification caused by the device resonance. However, for a quasi-static mirror, a mirror often works with vertically offset comb drive which are more complex to build so that the mirror can be statically controlled and maintain the tilting position stability via the control of the actuator. The quasi- static mirror also does not get the benefit of the mechanical amplification, which means the actuator will need to be more powerful to deflect the mirror that has same mass and stiffness as a resonant mirror. The disclosed invention provides a solution to make quasi-static mirror with powerful comb drive that is compatible with large angular displacement but allows a micro mirror to work with a robust flexure system that is capable of rotating to over 15 deg without reaching to yield strength of the silicon material.

[0010] The present invention relates to MEMS devices that have comb drives and flexures that generate out-of-plane motion. The comb drive as illustrated in the patent drawings includes a two set of comb fingers that is anchored on one or more sides so its stationary, and they are interdigitated with another two set of comb fingers that is anchored on a backplane in opposite directions and backplane is anchored to flexure to make the set of comb fingers is movable. The stationary combs are vertically offset from the movable fingers and generate out of plane motion when voltage is applied. The two sets of movable comb fingers that are opposing to each other will generate cancelling lateral force on the structure to ensure the force applied to the mirror stays as tangential on the rotating arc as they can. The cancelling pulling force reduces the requirement on lateral resistance on flexure and makes it more accepting to large torsional deformation without causing high stress on the flexure. The two sets of comb fingers anchoring on the movable part also increases the surface area of the comb drive by nearly 40%. The cancellation of lateral force on the vertical comb drive eliminates the need to use complex flexure design to ensure lateral stability during actuation. The pure rotation motion on the structural also allows for stress-sensing element to be used on the mirror to allow for accurate and linear position sensing response from the mirror. The two parts of stationary comb drive can be electrically decoupled with one part serving as driver of the mirror while the other part work as electrical damper to improve system stability, or work as position sensor to output the position of the mirror based on the changing of capacitance.

[0011] BRIEF DESCRIPTION OF THE DRAWINGS

[0012] These and other features will become more apparent from the following description in which reference is made to the appended drawings, the drawings are for the purpose of illustration only and are not intended to be in any way limiting, wherein:

[0013] Fig. 1 is a top view of prior art micro-mirror that rotates in two directions on one rotating axis;

[0014] Fig. 2 is a prospective view of the micro-mirror utilizing the self-balancing comb drive;

[0015] Fig. 3 is a partial prospective cross-section view of self-balancing comb drive;

[0016] Fig. 4A shows the stationary comb drive;

[0017] Fig. 4B shows the moveable comb drive;

[0018] Fig. 4C shows the stationary and movable comb drives together;

[0019] Fig. 5 is a self-balancing comb drive that has been actuated;

[0020] Fig. 6 is a modeling data showing the cancellation of the y components force when energized;

[0021] Fig. 7 is a show perspective view flexible flexure that has been disclosed in the past;

[0022] Fig. 8A is a the top view of a first variation of the comb finger; Fig. 8B is a the top view of a second variation of the comb finger;

[0023] Fig. 8C is a the top view of a third variation of the comb finger;

[0024] Fig. 8D is a the top view of a forth variation of the comb finger;

[0025] Fig 9A is a prospective view of the self-balancing comb drive with additional support;

[0026] Fig. 9B is a partial prospective view of a portion of the comb drive showing the anchor and reinforcement beam;

[0027] Fig. 10 is a partial prospective cross-section view of a variation of the self-balancing comb drive;

[0028] Fig. 11 is a partial prospective cross-section view of a further variation of the self-balancing comb drive;

[0029] Fig 12. is a top view of the self-balancing comb drive configured to provide a sensing function;

[0030] Fig 13. is a top view of the self-balancing comb drive configured to provide a breaking function;

[0031] Fig. 14 is a top view of a self-balancing comb drive which comprises comb drives arranged in series; and

[0032] Fig. 15 is a perspective view of pairs of self-balancing comb drive working together to generate piston motion on a MEMS device.

[0033] DETAILED DESCRIPTION OF THE INVENTION

[0034] An electrostatic and quasi-static MEMS mirror often has limited tilting angle as the available overlapping area of the parallel plates are often constrained by the fabrication material and technique. The present invention allows for large range of motion (for example, approximately 15 degrees or more) in the tilting direction on the single axis tilting mirror. Figure 2 shows one embodiment of a MEMS mirror having a large range of motion. The micro-mirror 10 that consists of at least one comb drive. In the preferred embodiment shown in the figures, four comb drives 2a, 2b, 2c and 2d are used. Each comb drive 2a-d having a movable comb drive portion 4a, 4b, 4c and 4d, a stationary comb drive portion 6a, 6b, 6c and 6d, and a reflector 8. Each movable comb drive 4a-d is coupled to an anchor 12a and 12b. Each anchor 12a and 12b having at least one flexure. In the preferred embodiment shown in the figures, each anchor 12a and 12b have two flexures 14a, 14b, 14c and 14d. The flexures 14a-d facilitate rotation of the moveable comb drives 4a-d at a position offset from their relative anchor 12a and 12b.

[0035] The movable comb drive 4a-d extended from the reflector 8. The reflector 8 can be of any shape or size, however in the preferred embodiment shown in the figures, the reflector 8 is a circle. The movable comb drives 4a-4d are coupled to the stationary bottom layer via anchors 12a and 12b. The micro mirror reflector 8 rotates in two directions (as shown by the arrows) about the anchors 12a and 12b.

[0036] To actuate the mirror, the stationary comb drives 6a-d and movable comb drives 4a-d are subjected to a potential difference generated by a voltage source. This induces an electric field and result in an attractive electrostatic force on the movable comb drive 4a-d. Defining the first rotating direction to be positive tilting (towards the top right of the figure), the parts of stationary comb 6a and 6c, are applied with a voltage simultaneously. Since the movable mirror is connected to ground through anchors 12a and 12b, this attractive electrostatic force on moveable combs 4a and 4c produces a downward pulling force and causes the mirror to rotate along the flexible flexures14a-b and 14c-d respectively. Conversely, the negative tilting (towards the bottom left of the figure) is initiated when a voltage is applied on parts of stationary comb6b and 6d. This creates and attractive electrostatic force that attracts moveable comb drives 6b and 6d to stationary comb drives 4b and 4d respectively. This causes the mirror to rotate in a negative tilting direction along the flexible flexures 14a-d.

[0037] Fig 3 shows a cross-section of a pair of self-balancing comb drive structure in more detail. The self-balancing comb drive 2b and 2c, which may be made of single crystal silicon, can be actuated in two directions and consists of two stationary combs 4c and 4d as the positive electrodes, and two moveable combs 6c and 6d. In this embodiment, 6c acts as the positive rotation comb and 6d acts as the negative rotation comb. The movable combs 6c and 6d are coupled to the substrate by a common anchor 12b. The moveable combs 4a-d is grounded by anchors 12a and 12b. the movable combs 4a-d further comprise support bars 16a, 16b, 16c and 16d. These backplanes or support bars 16a-d are generally parallel to and laterally offset from the anchor bars 12a and 12b. Since anchors 12a and 12b are grounded, the movable combs 4a-d act as a grounding electrode. The grounding electrode is electrically isolated from the stationary combs 6a-d . The rest of grounding electrode is thus electrically neutral via the connection to anchors 12a and 12b. The ground electrode is movable and pivoting around the flexures 14a-d. While the preferred embodiment has two flexures on each anchor, it is possible to have other arrangements of flexures along the length of the anchor. The ground electrode allows for two direction rotation via two movable combs, as described above. The moveable combs 4a and 4c are interdigitated and vertically offset from the stationary combs 6a and 6c respectively. The two movable comb 4a and 4c are anchored to substrate via support underneath of anchor 12a to the bottom layer where stationary combs 4c and 4d are located. Electrically isolation is formed via the buried oxide underneath the stationary comb layers. . The backplane 16a may or may not enclose the movable comb 30 depends on the design requirement if additional reinforcement of the structure is needed.

[0038] Fig 4a, b and c. show the self-balancing comb in detail. It can be appreciated that the selfbalancing combs 2a-d all have similar structures and thus 2a will be used as an example to describe the structure of stationary combs in Fig. 4a. Fig 4a shows an example of one embodiment of one of the stationary combs 6b Stationary comb 6b is a negative rotation comb. The negative rotation comb 6b consists of a first bank of comb fingers 18 and a second bank of comb fingers 20, with the first and second banks of comb fingers being configured in an opposing configuration. The first bank 18 is anchored from the bottom to the base substrate by stationary anchor 22, while the second bank 20 is anchored by the bottom to the base substrate by stationary anchor 24. In one embodiment, the comb fingers are free standing and coupled directly to the base substrate. In this embodiment the stationary anchors 22 and 24 are optional. In another embodiment, the comb fingers 18 and 20 are suspended from the stationary anchors 22 and 24. The two-opposing bank of comb fingers 18 and 20 are configured such that their free ends face inward towards each other. The two bank of comb fingers 18 and 20 are connected to the same electrical potential. In one embodiment, they are connected electrically via connection beam 26 or may be connected via wire bond wire.

[0039] Fig 4b shows part of the movable comb or ground electrodes. Similar to figure 4a above, figure 4b uses moveable comb 4b the negative rotating movable comb 4b which consists of anchor 12a, flexible flexures 14a and 14b, a short comb fingers bank 28, the long comb fingers bank 30, the backplane or support bar 16b. While the preferred embodiment shown in the figures has a short comb bank 28 and a long comb bank 30, it can be appreciated that the combs on either side of the support bar 14b can be of equal or length. Alternatively, comb bank 28 could be longer in length than comb bank 30. Furthermore, the preferred embodiment includes two flexible flexures 14a and 14b in line with anchor 12a to form the rotating axis of the movable comb 4b, however, it can be appreciated that more flexures could be included along the length of anchor 12a to provide more flexure. The short comb finger bank 28 is positioned and anchored on the far side of the backplane or support bar 16b with respect to the anchor 12a. The short comb finger bank 28 is interdigitated and vertically offset with stationary comb drive 22 and has the far side free standing from support bar 16b to allow for the clearance as the movable comb drive 4b rotates into the stationary comb 6b. The long comb finger bank 30 is positioned and anchored on the inside of the backplane or support bar 16b with respective to the anchor 16b. The long comb finger bank 30 is interdigitated and vertically offset from stationary comb drive 24 and has the close side of the combs free and un-enclosed to allow for the clearance as the comb drive rotates into the stationary comb bank 24. The negative rotating comb 4b may have reinforcement beam 32 connecting the short finger bank 28 and long finger bank 30 to anchor 12a. The reinforcement beam 32 is coupled to the anchor at a first end thereof and to the support bar 16b at a second end thereof. This allows the outside end of the mobile comb drive 4b to be supported from lateral movement. On an opposite end of the support bar 16b, the support bar is coupled to the anchor 12a through reflector 8. This arrangement allows for greater support for larger and / or heavier reflectors. Fig 4c shows the interdigitated and vertically offset fingers 18, 20, 28 and 30assembled together. As shown in Fig 5. the movable comb rotates into the stationary comb causing the structure to pivot around the flexible flexures 14a and 14b. It is notable that in the embodiment that includes connection beam 26 in the stationary comb drive 6b, the connection beam 26 may be spaced from the combs most distal from the reflector 8. This space allows for the rotational movement of reinforcement bar 32 on the moveable comb drive 4b into the space between the connection beam 26 and the most distal stationary combs.

[0040] Fig 6. Reveals the data from finite element analysis (FEA) for the self-balancing comb drive 2a- d that shows how the undesirable lateral force components are cancelled during actuation. The self-balancing comb drive 10 has two conductor_1 and conductor_ 3 representing part 22 and part 24 respectively, vice versa, conductorJD and conducto_2 represent the counterpart on the right side of the mirror body 8. As shown, the y force component that exerted on the pivoting mirror body 8 and flexible flexures 14a-d will be cancelled out and reach to zero while keeping the z force component the same. As a result, the design of flexible flexure 14a-d can be simplified and be more acceptable to high deformation and reach to high tilting angle without causing high stress in the flexure and hence increase the reliability and manufacturing ability of the MEMS device.

[0041] The flexible flexure 14a-d from disclosed micro-mirror 10, or flexible flexure 205 from its predecessor 20 may be placed with various design and remain compatible with the selfbalancing comb drive 2a-d. Fig 7. Reveals the various flexible design that has been proposed to overcome the flexible stability when large electrostatic forces are generated on the comb and resulted in sideway pulling of the flexure. The illustrations showed that the flexible flexures are anchored on the anchors 44 and carries suspended mass 40. The disclosed invention - selfbalancing comb drive avoids the implementation of these uniquely designs flexure which may be subject to lower yield strength as they encounter large angular displacement. A simplified straight beam flexure 902 as shown in Fig 9 can accept higher torsional stress while having the similar torsional stiffness. The straight beam flexure 902 working in combination of the self- balance comb drive produce highly linear stress change in the beam and making it ideal for piezo-resistive sensing element.

[0042] Fig 8. Reveals the various comb finger designs that may be applicable to this disclosed invention. Fig 8a is the top view of typical comb finger design which has rectangular shape 803 with a short side 801 and a long side 802. Rectangular comb 803 has one short end fixed and anchored to the structure and the other short end 801 open to allow the movable comb to move through. Fig. 8d gives the example how the two set of comb fingers that may be or may not have vertical offset from one another, has one movable 810 and one stationary 811 interdigitated each other and anchored on the opposing end. Fig. 8b reveals the variation 806 of the finger design 801 which consists of a long side 805 to maximum surface area of the comb drive, a wider anchoring side 812, and short opening side 805 to enhance the rigidity when a large electrostatic force is generated by high voltage. Fig. 8c reveals a modification of the 806, 809 which consists of a long side 808 to maximum surface area of the comb drive, a wider anchoring side 813, and a rounded shorter side 807 to improve the pointing electric field line to reduce the undesirable lateral pulling force occurs on the tip of the comb finger.

[0043] Fig 9. To make a power comb drive and high scanning speed, a structural reinforcing bar 32 is designed to support the comb drive while may deform during actuation and causing instability. The combination of the reinforcement beam 32 and the support bar 16 encloses figures 30. However, fingers 30 need to be interdigitated and vertically offset from the stationary fingers 20. In one embodiment, this is accomplished by thinning out part of the anchor 12a to create a projection 901 that is extending outwardly from anchor 12a. This provides thinner first support for flexure 902. The corner 904 and connection beam 32 are preferably the same thickness as projection 901. Since the corner 904 and connection beam 32 will move and rotate when the comb drive is in use, this thinning ensures there is clearance to move without interference with the connection beam 32 on the stationary comb drive 6. However, in an embodiment where the connection beam 32 is omitted, feature 901 may be avoided. One such embodiment is when the first stationary comb bank and second stationary comb bank are electrically coupled to through the base as shown in figure 10. The MEMS mirror discloses herein may be adapted for use in various applications, such as applications that require mirror position feedback. In this embodiment shown in figure 11 , the first stationary comb bank 18 and second stationary comb bank 20 are electrically decoupled. While there are several methods to accomplish this decoupling, in the preferred embodiment, the stationary comb banks 18 and 20 electrically decoupled via DRIE etching as they are etched down to the buried oxide 21 that is sitting between the drive and substrate. Flexure 14 is anchored to central support anchor 12 which is anchored to the substrate through the stationary comb drive layer but electrically decoupled via DRIE as well. In embodiments where the comb drives or comb banks are decoupled, the MEMS mirror 10 can have tilt angle sensing function. Figure 12 shows an embodiment of a sensing capable comb drive 1000 which has the movable comb drive 1002, a stationary comb bank 1001 connects to bond pad 1005, and second stationary comb bank 1003 that connects to bond pad 1004. A drive signal may be sent to either bond pad 1005 or 1004 and actuate the movable comb drive 1000. The overlapping area of the comb fingers between the stationery and movable will change according to the electrostatic force generated by the drive signal, a capacitance readout circuit 1006 may be connected to the stationary comb drive that is not used for driving and detect the change of capacitance and report the position of the mirror to the system for feedback control. In an event where additional tilting angle is required the sensing comb drive can be electrically switch to the driving signal and generate the additional force to rotate the mirror statically. The decoupled comb drive can also work as electrical damper or brake to improve MEMS stability and reduce system overshoot during power on or when vibration is applied to the MEMS device. This embodiment is shown in figure 13.

[0044] The structure of the comb drives is particularly advantageous in embodiments which have large reflectors such as that shown in figure 14. In this embodiment reflector 2000 is supported by multiple comb drive pair 2002, 2004, 2006 and 2008. Comb drives 2002 and 2004 are coupled in series while comb drives 2006 and 2008 are coupled in series on a second side of the reflector 2000. This arrangement allows for more torque to be created and provides increased support for reflector 2000.

[0045] As result, the self-balancing comb drive may be configured to have stationary comb drive 18 and 20 working together to generate larger torque or it can be reconfigured to have stationary comb drive 18 connected to capacitance sensing electronic 1006 and produce mirror position feedback while comb drive 20 is connecting to high voltage power supply 1007 and produce driving torque to turn the mirror as showed in Figure 10b. Alternatively, one of the stationary comb drive 304 or 305 can be controlled separately by two power supplies 1007 and 1008 as shown in Figure 10c to realize agile scanning mirror with active electrical damper to improve device transient response.

[0046] While this disclosure has focused on the preferred embodiment which comprises four comb drives organized in two pairs (2a and 2b being the first pair and 2c and 2d being the second pair), it can be appreciated that the design has applications with any number of drives. For example, a single comb drive (for example, just 2a) could be used to support a levered reflector. The stationary comb banks could be coupled to create rotation in a single direction, or decoupled to allow for two direction rotation, sensing or rotation with breaking. In another embodiment, two comb drives are used (for example, 2a and 2c) and are configured on opposite sides of the reflector 8. As with the single comb drive above, each of the stationary comb drive banks of each comb drive can be coupled to create rotation in a single direction, or decoupled to allow for two direction rotation, sensing or rotation with breaking.

[0047] It can further be appreciated that a single comb drive pair can be used (for example 2a and 2b). In this embodiment, the reflector would be levered from both comb drives in the pair. In this embodiment, one of the drives can be used to create tilt in a first direction while the second drive creates tilt in a second direction. Alternatively, the two comb drives can be used for sensing applications or one drive can be used to drive movement of the reflector while the other drive is used to break the movement.

[0048] In yet a further embodiment, the self-balancing comb drive 1 may also be utilized to generate piston motion by a leveraging design 1100. The piston moving device 1100 may consist of a pair or multiple pairs of self-balancing comb drive 1101 and 1102 that are placed in face-to-face direction. Each pair of self-balancing comb drives are anchored on the base and generate out- plane-motion on levers 1104 that is connected to platform 1103, or a reflective surface, or proof weight. All the actuators 1101 and 1102 will be driven synchronously by connecting to one driving signal to generate vertical displacement on each of connecting join 1105 of the platform 1103 and causes it move vertically normal to front surface of substrate. The actuators 1101 and 1102 may also be driven with separate driving signals and generate vertical displacement on the connecting join 1105 of platform 1103 in opposite direction and result in a tilting motion. The connecting join 1105 will be flexible and accept deformation and may be anchored to different location on the platform depends on designs.

[0049] Although the invention has been described with reference to certain specific embodiments, various modifications thereof will be apparent to those skilled in the art. The invention should not be limited to the examples described in the description but should be given the broadest interpretation consistent with the specification as a whole.

Claims

CLAIMS:

1. A micromirror comprising a base substrate; a reflector; at least one comb drive having a moveable comb component and a stationary comb component; and said reflector coupled to said moveable comb component; said movable comb component being pivotally coupled to said base substrate by an anchor bar said anchor bar coupled to and supporting a support bar offset to a first side of said anchor bar; said moveable comb component having combs extending from a first side of said support bar and a second side of said support bar; said stationary comb component having a first bank of combs and a second bank of combs, each bank of combs having a stationary anchor coupling said first bank of combs and second bank of combs to said base substrate; wherein combs extend from one side of said stationary anchor; said first bank of combs and said second bank of combs spaced from each other with said combs extending inwardly between the first bank and second bank; wherein said moveable comb component is positioned between said first bank of combs and said second bank of combs and facilitate cooperation therewith.

2. The micromirror of claim 1 wherein said at least one comb drive comprises two comb drives, a first comb drive and a second comb drive, located on opposite sides of said micromirror.

3. The micromirror of claim 1 wherein said at least one comb drive comprises two comb drives, a first comb drive and a second comb drive making a first comb drive pair; said first comb drive and said second comb drive positioned adjacent each other; wherein the movable component of the second comb drive is coupled to a second side of said anchor bar opposite said first side of said anchor bar.

4. The micromirror of claim 3 wherein said at least one comb drive further comprises a second comb drive pair having a third comb drive, a for the comb drive and a fourth comb drive, positioned adjacent each other and on an opposite side of said reflector from said first comb drive pair. wherein the movable component of the fourth comb drive is coupled to a second side of said anchor bar opposite said first side of said anchor bar.

5. The micromirror of any one of claims 1 to 4 wherein said anchor bar comprises a first hinge and a second hinge to facilitate rotation of the movable comb component.

6. The micromirror of claim 5 wherein the anchor bar has a length and the first hinge and a second hinge are positioned proximal to opposite ends of the length of the anchor bar.

7. The mircromirror of any one of claims 1 to 6 wherein said first comb bank and said second comb bank are eclectically coupled.

8. The mircromirror of any one of claims 1 to 6 wherein said first comb bank and said second comb bank are eclectically coupled via a first connection beam.

9. The micromirror of any one of claims 1 to 6 wherein said first bank is configured to receive a first electrical input and said second bank is configured to receive a second electrical input; wherein the first electrical input to said fist bank is used to drive a first set of combs on the first side of the support bar of the movable component while the second electrical input is to the second bank is used to cooperate with a second set of combs on the second side of the support bar to provide a breaking force to the moveable component.

10. The micromirror of any one of claims 1 to 6 configured to be used a sensor; wherein said moveable component is grounded;said first bank is configured to receive a first electrical input and said second bank is coupled to a capacitance readout to measure the capacitance between the grounded movable component and the second bank.11 . The micromirror of any one of claims 1 to 10 wherein additional comb drives are coupled to and positioned in line with and extending outwardly along a length of the comb drives to create a series of comb drives.

12. A micromirror comprising a base substrate; a reflector; at least one comb drive pair comprising a first comb drive having a first moveable comb component and a first stationary comb component; and a second comb drive, adjacent said first comb drive having a second moveable comb component and a second stationary comb component; wherein said reflector coupled to said first moveable component on a first side thereof and coupled to said second moveable comb component on a second side thereof; said first moveable comb component having combs extending from a first side of a first support bar and a second side of said first support bar; said second moveable comb component having combs extending from a first side of a second support bar and a second side of said second support bar positioned between said first stationary comb component and said second stationary comb component; said first support bar and second support bar each suspendedly support by a central support bar; the central support bar being pivotally coupled to said base substrate;; said first stationary comb component having a first bank of combs and a second bank of combs, and said second stationary comb component having a third bank of combs and a fourth bank of combs; each bank of combs having a stationary anchor and combs extending from one side of said stationary anchor;said first bank of combs and said second bank of combs spaced from each other with said combs extending inwardly between the first bank and second bank; said third bank of combs and said forth bank of combs spaced from each other with said combs extending inwardly between the third bank of combs and forth bank of combs; wherein said first moveable comb component is positioned between and to cooperate with said first bank of combs and configured to cooperate therewith, and said second bank of combs and said second moveable comb component is positioned between said third bank of combs and said forth bank of combs.

13. The micromirror of claim 12 wherein said at least one pair of comb drives comprises two pairs of comb drives located on opposite sides of said micromirror.

14. The micromirror of claim12 or 13 wherein said central support bar comprises two hinges to facilitate rotation of the said first movable comb component and second movable comb component relative to said base substrate.

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