CN1708449A - Microactuator provided with displacement detection function, and deformable mirror provided with this microactuator - Google Patents
Microactuator provided with displacement detection function, and deformable mirror provided with this microactuator Download PDFInfo
- Publication number
- CN1708449A CN1708449A CN 200380102310 CN200380102310A CN1708449A CN 1708449 A CN1708449 A CN 1708449A CN 200380102310 CN200380102310 CN 200380102310 CN 200380102310 A CN200380102310 A CN 200380102310A CN 1708449 A CN1708449 A CN 1708449A
- Authority
- CN
- China
- Prior art keywords
- moving element
- displacement
- microactrator
- drive signal
- displacement detecting
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000006073 displacement reaction Methods 0.000 title claims abstract description 344
- 238000001514 detection method Methods 0.000 title claims abstract description 57
- 230000008859 change Effects 0.000 claims abstract description 25
- 238000012937 correction Methods 0.000 claims description 73
- 230000006870 function Effects 0.000 claims description 53
- 230000009466 transformation Effects 0.000 claims description 29
- 230000009471 action Effects 0.000 claims description 26
- 238000000034 method Methods 0.000 claims description 21
- 239000000758 substrate Substances 0.000 claims description 20
- 238000005259 measurement Methods 0.000 claims description 12
- 230000004044 response Effects 0.000 claims description 11
- 230000033228 biological regulation Effects 0.000 claims description 7
- 230000007115 recruitment Effects 0.000 claims description 5
- 239000000284 extract Substances 0.000 claims description 4
- 230000000977 initiatory effect Effects 0.000 claims description 3
- 238000004321 preservation Methods 0.000 claims description 2
- 230000001915 proofreading effect Effects 0.000 claims description 2
- GOLXNESZZPUPJE-UHFFFAOYSA-N spiromesifen Chemical compound CC1=CC(C)=CC(C)=C1C(C(O1)=O)=C(OC(=O)CC(C)(C)C)C11CCCC1 GOLXNESZZPUPJE-UHFFFAOYSA-N 0.000 claims description 2
- 230000007613 environmental effect Effects 0.000 abstract description 10
- 238000005755 formation reaction Methods 0.000 description 49
- 230000015572 biosynthetic process Effects 0.000 description 47
- 239000003990 capacitor Substances 0.000 description 14
- 230000008569 process Effects 0.000 description 14
- 239000000203 mixture Substances 0.000 description 9
- 238000010586 diagram Methods 0.000 description 8
- 238000005516 engineering process Methods 0.000 description 8
- 238000009413 insulation Methods 0.000 description 7
- 238000006243 chemical reaction Methods 0.000 description 6
- 230000000694 effects Effects 0.000 description 6
- 230000001276 controlling effect Effects 0.000 description 5
- 238000004519 manufacturing process Methods 0.000 description 5
- 230000003287 optical effect Effects 0.000 description 5
- 230000035945 sensitivity Effects 0.000 description 5
- 101100490563 Caenorhabditis elegans adr-1 gene Proteins 0.000 description 4
- 239000012467 final product Substances 0.000 description 4
- 230000004888 barrier function Effects 0.000 description 3
- 230000005540 biological transmission Effects 0.000 description 3
- 230000000295 complement effect Effects 0.000 description 3
- 230000006835 compression Effects 0.000 description 3
- 238000007906 compression Methods 0.000 description 3
- 238000002474 experimental method Methods 0.000 description 3
- 238000007667 floating Methods 0.000 description 3
- 238000012360 testing method Methods 0.000 description 3
- 238000012546 transfer Methods 0.000 description 3
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 2
- 238000009825 accumulation Methods 0.000 description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 2
- 229910052782 aluminium Inorganic materials 0.000 description 2
- 239000004411 aluminium Substances 0.000 description 2
- 238000013459 approach Methods 0.000 description 2
- 238000003491 array Methods 0.000 description 2
- 238000004364 calculation method Methods 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 238000009792 diffusion process Methods 0.000 description 2
- 230000008034 disappearance Effects 0.000 description 2
- 230000008676 import Effects 0.000 description 2
- 229910021420 polycrystalline silicon Inorganic materials 0.000 description 2
- 229920005591 polysilicon Polymers 0.000 description 2
- 230000000717 retained effect Effects 0.000 description 2
- 239000004065 semiconductor Substances 0.000 description 2
- 229910052710 silicon Inorganic materials 0.000 description 2
- 239000010703 silicon Substances 0.000 description 2
- 101100388220 Caenorhabditis elegans adr-2 gene Proteins 0.000 description 1
- 229910008293 Li—C Inorganic materials 0.000 description 1
- 230000003044 adaptive effect Effects 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000000151 deposition Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 238000003780 insertion Methods 0.000 description 1
- 230000037431 insertion Effects 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 230000007261 regionalization Effects 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
Images
Landscapes
- Micromachines (AREA)
Abstract
While a drive signal is being given to a movable element (Ai) such as an electrostatic drive actuator to displace it, a displacement detector (6) detects the displacement. A calibration unit (15) self-calibrates the relation between a drive signal and a displacement to thereby correct a change with time in actuator characteristics and an environmental change. A switching unit (7) selectively connects one displacement detection unit to a plurality of movable elements (Ai) so as to reduce a displacement detecting circuit.
Description
Technical field
The present invention relates to the deformable mirror (deformabl mirror) that has the microactrator of displacement detection function and comprise this microactrator.In addition, relate to the various device that has adopted such microactrator.
Background technology
According to the MEMS that has adopted semiconductor technology (Micro Electro Mechanical Systems: microelectromechanical systems) technology, developed various microactrators.According to the MEMS technology, because simultaneously integrally formed a plurality of actuators and driving circuit etc. are expected so applied flexibly the application of this characteristic.The deformable mirror of having arranged a plurality of tiny mirror on substrate also is one of them.Deformable mirror is applied in the various devices of compensate for optical device, display and optical communication etc. that the corrugated aberration of light is revised effectively.
About the control of the displacement of deformable mirror, 2 kinds of methods that known in the past employing is following.
A kind of is open loop control, it is the driving voltage that applies multistage, the method of the displacement of control catoptron (for example, R.W.Corrigan, D.T.Amm and C.S.Gudeman " the raster brightness value technology of emission display " deliver Japan Kobe in international display works conference, on Dec 9th, 1998, opinion code LAD5-1).In the document, deformable mirror is used as the refraction dot matrix by catoptron displacement control refraction light quantity, the displacement of multistage ground open loop control deformable mirror.In the document, put down in writing in prior manufacturing process by experiment, measure the relation between Multipoint Drive voltage and the diffraction light quantity, map table is made in this insertion, to the scattered technology of revising of every specific character of deformable mirror.
Another method is the closed-loop control that has utilized external sensor, for example, in the compensate for optical device, utilizes wavefont sensor, generates the control signal of deformable mirror from the error signal that detects, and carries out closed-loop control.(for example, J.A.Perreault, T.G.Bifano etc. " adopting the adaptive optics of microelectron-mechanical deformable mirror to proofread and correct ", optical engineering, Vol.41, No.3, pp.561-566 (2002.3)).
In addition, in the microsensor field, following technology is known.In pressure transducer, have variation by electrostatic capacitance, detect and bring the sensor of the distortion of barrier film (diaphragm) by external pressure.(for example, S.B.Crary, W.G.Baer etc., " digital compensation of high performance silicon pressure transducer ", sensor and actuator, A21-A23, pp.70-72 (1990)).In the document, put down in writing under the various temperature condition, in advance by experiment, obtain the relation of pressure and sensor output, the correction polynomial expression that is similar to these relations is stored in formation in the storer.
In addition, also exist to eliminate external pressure and produce electrostatic force by other electrode like this, the distortion essence that makes barrier film is zero to control like this, is obtained the pressure transducer of equalized pressure (Force Balanced) type of external pressure by the size of this electrostatic force.(for example, B.P.Gogoi, C.C.Wang, C.H.Mastrangelo, " equilibrant micro equipment pressure transducer ", IEEE electronic equipment journal, Vol.48, No.8, pp.1575-1584 (2001.8)).
In angular-rate sensor, there is the Coriolis force (Coriolis force) that takes place with angular velocity, the sensor of the amount by the displacement of electrostatic capacitance change detection moving element from the outside.(for example, T.Juneau, A.P.Pisano, J.H.Smith, the twin shaft of the micro equipment speed revolving gear " operation ", sensor ' 97,1997 solid state sensor and actuator international conference, Chicago, June 16-19, pp.883-886).In the document, put down in writing according to the formation that can change the initial position drift correction zero point drift of element.
But, in above-mentioned such microactrator, have following problem.
Make the sensor that map table carries out open loop control in manufacturing process, the data acquisition of its map table is numerous and diverse and there is limit in the correspondence with long variation or environmental change etc.For example, in order to obtain the relation of driving voltage and diffraction light quantity, in fact for light from the outside, it is necessary that per 1 pixel is measured light quantity, when needing special-purpose measurement mechanism, the identical operation that waits in the position of luminous point is a lot, and data acquisition is extremely numerous and diverse.In addition, can measure just in the characteristic at initial stage of manufacturing process, under the state in the actual installation auto levelizer, the displacement of surveillance operation portion is impossible.Therefore, even when the environmental change along with long-time variation and temperature etc., actuator characteristics changes, and can not carry out corresponding therewith correction.
The sensor that utilizes the external sensor of wavefont sensor etc. to carry out closed-loop control, at first as its 1st problem, the formation costliness of control.In order to carry out stable closed-loop control, the detection of wavefont sensor is counted needs the actuator number of variable ratio shape catoptron many, for example general in Shack-Hartmann type wavefont sensor, detect count need be at the actuator number about more than 2 times.Therefore, in order to carry out closed-loop control, need more high-resolution sensor, in addition, also need to make the critically corresponding position adjustment of each drive point of each check point and the deformable mirror of wavefont sensor.Further, from the computing that a plurality of detection signals carry out that the corrugated reconstructs etc., the control circuit that generates the control signal of each drive point also is need be than higher precision, large-scale circuit.In addition, be the big this point of bringing by wavefont sensor of light loss as the 2nd problem.Because wavefont sensor uses the part as the light beam of the correction object on corrugated to detect the corrugated, this is the loss cause of light quantity.The increase because the detection on closed-loop control corrugated is counted is at each check point, if want to guarantee certain sensor sensing sensitivity (S/N), because the big light loss of wavefont sensor will produce.
In addition, in the microsensor of pressure transducer and angular-rate sensor etc., exist on following such formation feature and by its problem of bringing.At first, the 1st, just can change element to 1 carries out displacement detecting and control to the microsensor of putting down in writing in aforesaid document, but need drive under the situation of a plurality of actuators simultaneously like this when resembling deformable mirror, if each actuator is carried out closed-loop control, there is for this reason the circuit scale greatly such problem that becomes.Promptly each circuit for the detection signal generator of displacement detecting, amplifier, A/D transducer, control circuit etc. need have identical quantity with actuator, particularly under the many situations of actuator number, exist circuit scale to become big, the such problem of cost up that chip is all.
As the 2nd problem, the record relation of measuring drive signal and displacement is not carried out the formation of self-correction, and the purposes that is used to make the displacement accuracy of actuator to improve in the past technology is difficult.Though pressure transducer and angular-rate sensor also comprise the power of giving by the outside, with the moving element of displacement and the shift transformation of this moving element is the formation of sensor output, but the correspondence during this conversion is to have utilized the relation of storing in storer in advance, except the drift correction at zero point, the displacement of moving element and the corresponding relation of output are fixed.Because the zero point drift correction is not have the side-play amount of the state of displacement to revise to moving element, so the relation of this and drive signal and displacement is what it doesn't matter in essence.That is, for example,, can not revise it even exist owing to repeat the variation in time of such mechanical property such as tired elastic constant variation.
Promptly, when giving displacement to actuator, the relation of its drive signal and displacement is carried out all not having in any document of being formed in of self-correction record, and for long-time variation and various environmental change, the actuator characteristics that compensation changes in big scope is difficult.
Summary of the invention
In order to address the above problem, the object of the present invention is to provide a kind ofly with simple formation, for revising with the characteristic of long-time variation or environmental change is scattered, carry out the microactrator and the deformable mirror of the position control of high reliability.
Microactrator of the present invention comprises: substrate; Moving element, it is supported on the described substrate movablely; Drive division, its output are used to allow the drive signal of described moving element displacement; Transformation component, it keeps the displacement of described moving element and the corresponding relation between the described drive signal; Displacement detecting portion, it detects in the displacement of having given the described moving element under the described driving status signal; And correction unit, the corresponding relation that it utilizes the described transformation component of output calibration of described drive signal and described displacement detecting portion to keep.
In a preferred embodiment, described moving element is the moving element of electrostatic, is included on the described substrate fixing fixed electorde and the float electrode of facing mutually with described fixed electorde; The displacement of described moving element detects according to the variation of the electrostatic capacitance between described fixed electorde and described float electrode in described displacement detecting portion.
In a preferred embodiment, described drive division with near the 1 subresonance frequency of described moving element or the low frequency signal below it export as described drive signal; Described displacement detecting portion overlaps the high-frequency signal more than the 1 subresonance frequency of described moving element on the described drive signal.
In a preferred embodiment, described drive division is exported substantial dc voltage as described drive signal.
In a preferred embodiment, described drive division is exported the described dc voltage of multistage as described drive signal; The displacement of described moving element detects in described displacement detecting portion in each section of described multistage; Described correction unit is approximate with the approximate function of prescribed form with the output of the dc voltage of described each section and described displacement detecting portion.
In a preferred embodiment, the described drive division low frequency signal that will have a multistage frequency is exported as described drive signal; The displacement that adds the described moving element that shakes detects in described displacement detecting portion; Described correction unit is corresponding with the output of displacement detecting portion with described drive signal, calculates the amplitude response or the phase response of described moving element.
In a preferred embodiment, described drive division is exported near the low frequency signal the 1 subresonance frequency of described moving element as described drive signal multistage; The displacement that adds the described moving element that shakes detects in described displacement detecting portion in each section of described multistage; Described correction unit makes described drive signal corresponding with the output of displacement detecting portion, extracts 1 subresonance frequency of described moving element.
In a preferred embodiment, when increase setting the amplitude of described drive signal, reduce to set the amplitude of the described high-frequency signal that described displacement detecting portion produces.
In a preferred embodiment, the described float electrode of described moving element comprises roughly symmetrical the 1st electric conductivity part and the 2nd electric conductivity part of axle in accordance with regulations, with described axle is that the center energy freely tilt supported versatilely, and described fixed electorde comprises the 1st electrode of partly facing mutually by the gap with the 1st electric conductivity of described float electrode and the 2nd electrode of partly facing mutually by the gap with the 2nd electric conductivity of described float electrode; Described drive division is applying described drive signal between described the 1st electric conductivity part and described the 1st electrode or between described the 2nd electric conductivity part and described the 2nd electrode; Described displacement detecting portion applies the 1st high-frequency signal on described the 1st electrode, on described the 2nd electrode, apply and described the 1st high-frequency signal same-amplitude and the 2nd opposite high-frequency signal of phase place, detect will described the 1st electric conductivity partly and the voltage of the terminal that partly is electrically connected of described the 2nd electric conductivity.
In a preferred embodiment, the corresponding voltage instruction value of displacement of described transformation component generation and described moving element; Described drive division comprises the DA converter of output corresponding to the described drive signal of described voltage instruction value; Described correction unit is proofreaied and correct the corresponding relation between the displacement of described voltage instruction value and described moving element.
In a preferred embodiment, described DA converter section has nonlinear characteristic, and the value of described drive signal is big more, reduces the recruitment of setting the described drive signal corresponding with described voltage instruction value more.
In a preferred embodiment, described correction unit is with the corresponding relation between the displacement of described voltage instruction value of 1 rank approximation to function and described moving element.
In a preferred embodiment, when power initiation, allow described correction unit move.
In a preferred embodiment, comprise temperature detecting part, when described temperature detecting part detects temperature variation more than the setting, allow described correction unit action.
In a preferred embodiment, comprise unusual judging part, when its output in described displacement detecting portion surpasses specialized range, judge the unusual of described moving element or described displacement detecting portion.
In a preferred embodiment, when described unusual judgement section judges when being unusual, forbid renewal by the described corresponding relation of described correction unit.
Have, microactrator of the present invention comprises: substrate again; Moving element, it is supported on the described substrate movablely; Drive division, its output are used to allow the drive signal of described moving element displacement; Displacement detecting portion, it detects the displacement of described moving element; And switching part, it optionally connects described drive division and/or described displacement detecting portion and described a plurality of moving elements each.
In a preferred embodiment, described switching part switches the displacement detecting object of described displacement detecting portion on one side with time series, Yi Bian detect the displacement of each described moving element.
In a preferred embodiment, comprise closed-loop control portion, it utilizes the output of described displacement detecting portion, the output of the described drive division of closed-loop control.
In a preferred embodiment, comprise that further open loop controls the open loop control part of the output of described drive division, switch described closed-loop control portion and described open loop control part, carry out the control of described moving element with time series.
In a preferred embodiment, described open loop control part comprises the preservation portion of the output of preserving the described drive division of controlling by described closed-loop control portion.
In a preferred embodiment, described moving element is configured to accumulate the electric charge corresponding to described drive signal; Described switching part switches to the 2nd state that described moving element is kept described electric charge as high impedance with described moving element with the 1st state that described closed-loop control portion links to each other.
In a preferred embodiment, comprise the counter of the time value that measurement links to each other with described closed-loop control portion about each described moving element and detect the convergent convergence detection portion of described closed-loop control; Even surpass the set upper limit value from the output of described counter, described convergence detection portion does not detect under the described convergent situation yet, and described switching part cuts off being connected of described moving element and described closed-loop control portion.
In a preferred embodiment, the time value that is connected with described closed-loop control portion about described moving element is the cycle index of described closed-loop control portion.
In a preferred embodiment, described convergence detection portion detects described convergence, described switching part switches to the moment of next moving element at the tie point of described closed-loop control portion, when the output of described counter does not reach under the situation of described higher limit, according to the output of described counter, change the higher limit of next moving element.
In a preferred embodiment, described switching part is with linking to each other with described displacement detecting portion simultaneously more than 2 among described a plurality of moving elements at least.
In a preferred embodiment, will be applied on the both sides of described fixed electorde and described float electrode with the equal above big or small bias voltage of the amplitude of described high-frequency signal.
Another microactrator of the present invention comprises: substrate; Moving element, it is supported on the described substrate movablely; Drive division, its output are used to allow the drive signal of described moving element displacement; Displacement detecting portion, it detects the displacement of described moving element; Switching part, it is set in the wiring path that connects between described drive division and/or described displacement detecting portion and the described moving element, switches between the state of state that connects described wiring path and cut-out; Correction unit, it utilizes in the 1st output of the described displacement detecting portion that obtains under the state that has connected described wiring path and has cut off the 2nd output of the described displacement detecting portion that obtains under the state of described wiring path, revises.
Another microactrator of the present invention comprises: substrate; Moving element, it is supported on the described substrate movablely; Drive division, its output are used to allow the drive signal of described moving element displacement; Displacement detecting portion, it detects in the displacement of having given the described moving element under the described driving status signal.Described moving element is included on the described substrate fixing fixed electorde and the float electrode of facing mutually with described fixed electorde; Described float electrode comprises roughly symmetrical the 1st electric conductivity part and the 2nd electric conductivity part of axle according to the rules, is that the center energy freely tilt supported versatilely with described axle; Described fixed electorde comprises the 1st electrode of partly facing mutually by the gap with the 1st electric conductivity of described float electrode and the 2nd electrode of partly facing mutually by the gap with the 2nd electric conductivity of described float electrode; Described drive division is created in the 1st drive signal that described the 1st electrode applies and has size different with described the 1st drive signal and the 2nd drive signal that applies at described the 2nd electrode.Described displacement detecting portion comprises: the high-frequency signal generating unit of exporting the above high-frequency signal of 1 subresonance frequency of described moving element, the 1st loaded impedance element that links to each other with described the 1st electrode at the 1st terminal, the 2nd loaded impedance element that links to each other with described the 2nd electrode at the 2nd terminal, the high-frequency detection portion that connects described the 1st terminal and described the 2nd terminal, with the terminal of the opposite side of described the 1st terminal of described the 1st loaded impedance element on applied described the 1st drive signal of described high-frequency signal overlapping, with the terminal of the opposite side of described the 2nd terminal of described the 2nd loaded impedance element on applied described the 2nd drive signal of described high-frequency signal overlapping.The displacement of described moving element detects by the relatively phase place and/or the amplitude of the described high-frequency signal between described the 1st terminal and described the 2nd terminal in described high-frequency detection portion.
Deformable mirror of the present invention comprises above-mentioned each microactrator; At least a portion at described moving element forms reflection region.
Device of the present invention comprises above-mentioned each microactrator.
Driving method of the present invention is used to drive the microactrator with moving element, comprising: output is used to allow the step of drive signal of described moving element displacement; Keep the displacement of described moving element and the step of the corresponding relation between the described drive signal; Detection is in the step of the displacement of giving the described moving element under the state of described drive signal; Utilize the output of described drive signal and described displacement detecting portion, the step of proofreading and correct described corresponding relation.
Description of drawings
Fig. 1 is the summary pie graph of microactrator in embodiments of the present invention 1.
Fig. 2 is the summary pie graph of the driving circuit of microactrator in embodiments of the present invention 1.
Fig. 3 is the process flow diagram of corrective action program in embodiments of the present invention 1.
Fig. 4 is the summary pie graph of microactrator in embodiments of the present invention 2.
Fig. 5 is the process flow diagram in embodiments of the present invention 2 discontinuous closed-loop control programs.
Fig. 6 is the summary pie graph of microactrator in embodiments of the present invention 3.
Fig. 7 is the process flow diagram in embodiments of the present invention 3 discontinuous closed-loop control programs.
Fig. 8 is the exploded perspective view of microactrator in embodiments of the present invention 4.
Fig. 9 is the summary pie graph of driving circuit 100a in embodiments of the present invention 4.
Figure 10 is the process flow diagram of corrective action program in embodiments of the present invention 4.
Figure 11 (a) and (b) be the curve map that is illustrated in the corresponding relation of voltage instruction value D and displacement in some moving elements.
Figure 12 is the summary pie graph of microactrator in embodiments of the present invention 5.
Figure 13 is the summary pie graph of microactrator in embodiments of the present invention 6.
The summary that Figure 14 (a) is illustrated in non-linear DA converter 176 in the embodiments of the present invention 6 constitutes, and Figure 14 (b) is for the curve map of the corresponding relation of voltage instruction value D and displacement Z in its correction unit 178 is described.
Embodiment
Below, explanation embodiments of the present invention in the time of with reference to accompanying drawing.
(embodiment 1)
At first, with reference to Fig. 1～3, the 1st embodiment according to microactrator of the present invention is described.The microactrator of present embodiment is the electrostatic actuator of active actions of tilting.Such microactrator for example adopts the semiconductor fabrication process fabrication techniques to obtain.The microactrator of present embodiment is applied to the reflection of light direction is carried out in the deformable mirror of multistage control.
At first with reference to Fig. 1.Fig. 1 is the summary pie graph of microactrator in the present embodiment.In Fig. 1, on substrate 1, driving circuit 2 is set as silicon wafer, be provided with the insulation course 3 of the above thickness of 30 μ m thereon.On insulation course 3, constitute the movable part 4 that constitutes by n (n is the integer more than 2) moving element A1～An.Moving element A1～the An of movable part 4 has identical formation mutually, herein, is that example describes with the individual moving element Ai of i (i is the following integer of 1 above n).Moving element Ai comprises: 2 fixed electorde E
Li, E
Ri, with these fixed electordes E
Li, E
RiThe float electrode Yi that the position faced mutually is provided with, freely tilt to support versatilely the support Pi of the pair of conductive of this float electrode Yi.
Moving element Ai is that the center is symmetrical shape with support Pi.Float electrode Yi has the 1st electric conductivity part Y
LiAnd the 2nd electric conductivity part Y
RiThe 1st electric conductivity part Y
LiBy gap and the 1st electrode E
LiRelatively, the 2nd electric conductivity part Y
RiBy gap and the 2nd electrode E
RiRelatively.The surface of float electrode Yi is as catoptrical catoptron performance function.
If at the 1st electrode E
LiAnd between the float electrode Yi, in addition, the 2nd electrode E
RiAnd give potential difference (PD) between the float electrode Yi, according to electrostatic force, float electrode Yi turns left or right-handed inclination activity.Its result, the light that the surface by float electrode Yi is reflected towards changing.By regulating the current potential extent, can control the angle of inclination of float electrode Yi.
Herein, by the 1st electrode E
Li, float electrode Yi the 1st electric conductivity part Y
LiThe electric capacity of the electric capacity that forms is C
Li, by the 2nd electrode E
Ri, float electrode Yi the 2nd electric conductivity part Y
RiThe electric capacity of the capacitor that forms is C
RiAt this moment, be under the original state of flat-hand position at float electrode Yi, C
Li=C
RiRelation roughly set up.
Capacitor C
Li, C
RiSize respectively according to the inclination activity displacement of float electrode Yi, to increase and decrease in the other direction.In the present embodiment, by detecting capacitor C
Li, C
RiThe variation of size, can detect the displacement of float electrode Yi.
Terminal T
Li, T
RiAnd T
PiRespectively with fixed electorde E
Li, E
RiAnd pillar Pi links to each other.These terminals link to each other with driving circuit 2 as the via hole that connects insulation course 3.
Then the detailed of driving circuit 2 is described with reference to Fig. 2.Fig. 2 is the summary pie graph of the driving circuit of microactrator in the present embodiment.
Driving circuit 2 comprises all control part 5 of control, detect the displacement detecting portion 6 of displacement of each moving element Ai and the switching part 7 of moving element that is selected to the measuring object of displacement detecting portion 6.
Control part 5 comprises: I/F portion 10, displacement of targets configuration part 11, transformation component 12, voltage instruction portion 13, displacement detecting control part 14, correction unit the 15, the 1st driving voltage generating unit the 20, the 2nd driving voltage generating unit 22.In the present embodiment, voltage instruction portion the 13, the 1st driving voltage generating unit 20 and the 2nd driving voltage generating unit 22 constitute " drive division ".
Carry out between I/F portion 10 and the outside about the order of control and the exchange of data.
Displacement of targets configuration part 11 determines each displacement of targets of moving element A1～An based on the output from I/F portion 10.
Transformation component 12 is transformed to target data about driving voltage with each displacement of targets of moving element A1～An.In transformation component 12, the driving voltage of each moving element A1～An and the corresponding relation of displacement are saved as map table.The characteristic of each moving element A1～An is scattered to be corrected at this.
Voltage instruction portion 13 is when carrying out the control of each moving element A1～An, and based on the output from transformation component 12, output is in order to make the voltage instruction value D (V of moving element A1～An displacement
L1)～D (V
Ln), D (V
R1)～D (V
Rn).Voltage instruction value D (V
L1)～D (V
Ln), D (V
R1)～D (V
Rn) be and fixed electorde used terminal T
L1～T
Ln, T
R1～T
RnThe driving voltage V that applies
L1～V
Ln, V
R1～V
RnCorresponding respectively.Voltage instruction portion 13 makes fixed electorde terminal T when detecting the displacement of moving element Ai in addition
Li, T
RiThe DC composition V of the driving voltage that applies
L, V
RDifferential part of V
L-V
RValue change like this at some official hours, make voltage instruction value D (V
L)～D (V
R) change.Example as this way adopts V herein
L, perhaps V
RIn one be set at 0V, make another begin the method that increases of voltage unit with regulation from 0V.V about 13 generations of voltage instruction portion
L, V
RControlling value and the time of variation, be based on that the output of displacement detecting control part 14 controls.
14 pairs of voltage instruction portions of displacement detecting control part 13 carry out in order to make voltage instruction value D (V
L), D (V
R) instruction that changes.In addition, make transistor 26 conductings of displacement detecting portion 6, make it keep official hour, the skew of removing detection signal Vout.Thus, by making voltage instruction value D (V
L), D (V
R) change the change that can remove the detection signal Vout of generation.
Correction unit 15 receives the voltage instruction value D (V of voltage instruction portion 13 outputs
L), D (V
R) and the testing result of the displacement of the moving element Ai of displacement detecting portion 6 output, make voltage instruction value D (V
L), D (V
R) and the corresponding relation of displacement.These relations by with the curve of approximation match of prescribed form, remove measuring error, in the map table of transformation component 12, to be saved by the form of interpolation.
The 1st driving voltage generating unit 20 is based on the voltage instruction value D (V from voltage instruction portion 13
L), produce dc voltage V
LThe 2nd driving voltage generating unit 22 is based on the voltage instruction value D (V from voltage instruction portion 13
R), produce dc voltage V
R
Displacement detecting portion 6 comprises: the 1st high-frequency signal generating unit the 21, the 2nd high-frequency signal generating unit 23, operational amplifier 24, capacitor 25, transistor 26, amplifier 27, AD transducer 28.
The 1st high-frequency signal generating unit 21 produces amplitude V
A, frequency f AC voltage.Frequency f is got the setting in the scope of 100kHz～1MHz, and this is that (1～10kHz) also wants big value for 1 subresonance frequency f 0 than moving element Ai.The 1st driving voltage generating unit 20 and the 1st high-frequency signal generating unit 21 are connected in series, as both and, obtain the 1st output voltage V
L+ V
ASin (2 π ft).
The 1st high-frequency signal generating unit 23 produces and the 1st high-frequency signal generating unit 21 same-amplitude V
A, frequency f, phase place 180.Different AC voltage.The 2nd driving voltage generating unit 22 and the 2nd high-frequency signal generating unit 23 are connected in series, as both and, obtain the 2nd output voltage V
R-V
ASin (2 π ft).
Under by the situation that switching part 7 is selected with moving element Ai is connected, the 1st and the 2nd output voltage V
L+ V
ASin (2 π ft), V
R-V
ASin (2 π ft) is transfused to terminal T respectively
Li, T
Ri, be transfused to operational amplifier 24 from the output of terminal Tpi.The output Vout of the circuit that is formed by the capacitor 25 of operational amplifier 24 and capacitor C f is with (formula 1) expression, because the 2nd of the right is according to driving voltage V
L, V
RChanges delta V
L, Δ V
RSkew, so as narrating,, this is removed, can precision obtain being used to detect electrostatic capacitance change C well if before detecting, make MOS transistor 26 conductings
Ri-C
LiSignal.
(formula 1)
Vout＝((C
Ri-C
Li)/Cf)·V
Asin(2πft)+(C
RiΔV
R-C
LiΔV
L)/Cf
Output Vout is amplified by amplifier 27, is transformed to numerical data at AD transformation component 28, to correction unit 15 outputs.
Switching part 7 is for each of moving element A1～An, at the drive pattern that carries out drive controlling with carry out changing between the detecting pattern of displacement detecting.Moving element Ai is set to detecting pattern in the drawings, and is such as already explained, links to each other with displacement detecting portion 6, studies its response characteristic.In addition, moving element Ai+1 is set to drive pattern in the drawings, fixed electorde terminal T
Li+1, T
Ri+1Be applied in voltage respectively by 13 instructions of voltage instruction portion, in addition, float electrode terminal T
Pi+1Link to each other with earthing potential, be driven to the target location.
Action for the microactrator of above such formation describes with reference to Fig. 3.Fig. 3 is the process flow diagram of the corrective action program of microactrator in the present embodiment.
When the temperature sensor of expression does not detect the above temperature variation of setting when device starts and/or among the figure, perhaps built-in timer count down to when the transform data of last time upgrades under the situation of actuation time more than the stipulated time etc., and the microactrator of present embodiment upgrades the map table that is kept at the moving element A1～An in the transformation component 12.
At first, make i=1 (step 30), as the moving element Ai that carries out displacement detecting, the 1st moving element A1 is selected.Switching part 7 is with moving element Ai link to each other with displacement detecting portion 6 (step 31).At this moment, the whole moving elements beyond the Ai were cut off with being connected of displacement detecting portion 6.
In displacement detecting, voltage instruction portion 13 makes the voltage instruction value D (V of output
L), D (V
R) change, make the output voltage V of the 1st driving voltage generating unit 20
LOutput voltage V with the 2nd driving voltage generating unit 20
RIn the time of multistage output, carry out the displacement detecting of moving element Ai at each section.Specifically, at first set V
RFor 0V (step 32), make V
LBegin till maximum voltage Vmax, to increase from 0V interimly, measure the displacement of moving element Ai in each voltage section.
The displacement data of measuring and each V
LValue is stored in the correction unit 15 (step 33) simultaneously.Then, V
LFor 0V (step 34), make V
RBegin till maximum voltage Vmax, to increase from 0V interimly, measure the displacement of moving element Ai in each voltage section.The displacement data of measuring and each V
RValue is stored in the correction unit 15 (step 35) simultaneously.Finish if measure, correction unit 15 is with voltage difference V
L-V
RWith the approximate function match of displacement data, calculate the every coefficient and the correlation (step 36) of approximate function with regulation.
To the every coefficient and the correlation of this approximate function, the scope that is judged as normal value in advance is set, and judges whether these values that obtain are in this normal range (step 37).Under the situation in normal range not, judge in measurement result, to have produced error (step 38) that the content of Error processing is according to the value of coefficient and correlation and difference, only have under the small situation about departing from normal range, measure again, for example, when not relying on V
L, and V
RMagnitude of voltage, moving element Ai does not almost have under the situation of displacement, judges that fault has appearred in moving element or displacement detecting portion 6, the rewriting of map table is forbidden in the demonstration that makes mistakes.
Under the situation in normal range, judge that measurement result is effective, upgrade map table (step 39), carry out the measurement (step 40) of next moving element.If the measurement of n moving element An finishes, map table make EOP (end of program).
If map table make end, microactrator is transferred to the control action that has utilized this table.Switching part 7 makes whole moving element A1～An be in the drive pattern that carries out drive controlling.
The control of moving element in the present embodiment is open loop control, if set the displacement of targets of each moving element A1～An by displacement of targets configuration part 11, be transformed to target data by transformation component 12 about driving voltage, apply the driving voltage by 13 instructions of voltage instruction portion, moving element A1～An is controlled as the appearance of expectation.
Microactrator according to the present embodiment of above explanation, because comprised the formation of the displacement that self-detection obtains by self driving force, so do not need outside deviation meter, need can not make the scattered map table of characteristic of revising indivedual moving elements extremely simply about numerous and diverse operation of settings such as the position coincide.
In addition, because can measure under the state in being assembled into device, so also the variation of the moving element characteristic that can bring with the environmental change with long-time variation and temperature etc. is corresponding.
Further, because switching part 7 is to carry out displacement detecting when 1 displacement detecting portion 6 and the conversion of a plurality of moving element are gone the rounds, even so comprise the actuator of a plurality of moving elements, the quantity that also can be used in the detection signal generator, amplifier, A/D transducer etc. of displacement detecting reduces significantly, can cut down circuit scale, cut down chip cost.
Also have, in the present embodiment, the example that driving voltage generating unit 20 is constituted respectively, is connected with high-frequency signal generating unit 21 is illustrated, but also can be that two parts are made of 1 DA transducer, to modulate with frequency f from the control signal of voltage instruction portion 13, obtain V
L+ V
AThe output of sin (2 π ft).In addition, the waveform of AC voltage is not sinusoidal wave, but square wave also can.For driving voltage generating unit 22 and high-frequency signal generating unit 23 also is same.Do like this, the circuit that a plurality of and drive controlling of the signal generating circuit that displacement detecting is used is used uses jointly, can seek all simplifications of circuit.
In addition, for 13 in voltage instruction portion with dc voltage composition V
L, V
RBe illustrated as variable example, but also can make the amplitude V of AC voltage composition
AVariable.The V that particularly works as potential difference (PD)
L-V
RWhen absolute value is big, if make amplitude V
ADiminish, have 2 kinds of following effects.The 1st, suppress because AC voltage composition to the influence of moving element displacement the time, can make detection sensitivity increase.V when potential difference (PD)
L-V
RAbsolute value hour, because the displacement of moving element Ai is little, the variation C of electrostatic capacitance
Li-C
RiAlso little, so the amplitude of detection signal Vout is little, be not easy to obtain the S/N ratio, on the other hand, because the suction that AC voltage composition produces at moving element Ai place is at fixed electorde E
LiOne side and E
RiOne side is almost cancelled out each other, so little to the influence of the displacement of moving element.The V of potential difference (PD)
L-V
RWhen absolute value is big, represent characteristic in contrast to this.If the i.e. V of potential difference (PD)
L-V
RAbsolute value hour makes amplitude V
ABecome big, the V of potential difference (PD)
L-V
RWhen absolute value is big, make amplitude V
ADiminish, can suppress because AC voltage composition to the influence of moving element displacement the time, can make detection sensitivity increase.The 2nd, for identical supply voltage, can widely obtain the scope of the possible displacement of the measurement of moving element.The scope of the displacement that the measurement of moving element is possible is by the setting range decision of dc voltage, and this is to have removed AC voltage composition voltage afterwards from all voltage.Driving voltage V
LPerhaps V
RAbsolute value when big, by making amplitude V
ALittle, for identical supply voltage, can enlarge the scope that moving element is measured possible displacement.
In addition, in the present embodiment, displacement detecting portion 6 is illustrated as 1 passage, also can constitute: displacement detecting portion 6 comprises a plurality of passages, all moving element A1～An also is split into a plurality of, each piece inside of each passage tours of inspection of displacement detecting portion 6.
In addition, in the present embodiment, moving element is to link to each other with displacement detecting portion 6 singly, but also can be that a plurality of moving elements link to each other with 1 displacement detecting portion 6 simultaneously.In such cases, the scattered quilt of each moving element is average, measures under the situation of variation of all characteristics, can carry out the good measurement of precision.For the environmental change of temperature characterisitic variation etc., all moving elements have under the situation of characteristic variations of almost certain vergence direction, and all correction data that obtain like this get final product with the transform data addition of indivedual moving elements.
In addition, in the present embodiment, drive signal has been got the DC signal, but be not limited to this, as the drive signal that can give the displacement of expectation to moving element, give the following low frequency drive signal of 1 subresonance frequency of moving element,, also can measure the response characteristic of moving element by measure the amplitude and the phase place of moving element by displacement detecting portion 6.In addition, drift about near 1 subresonance frequency of moving element by the frequency that makes drive signal, the search resonance point also can be measured the resonant frequency self of moving element, thus also can precision measures the response characteristic of moving element well.Correction unit 15 is calculated voltage one placement property of moving element from these response characteristics, can be kept at transformation component 12, so that utilize.By to about the 1 subresonance frequency f 0 of moving element and the elastic constant k of inclination activity, utilize the proportional such relation of square root of f0 and k, detect the variation of 1 subresonance frequency f 0, also can proofread and correct the relation of driving voltage and displacement statically.
In addition, in the present embodiment, adopt the displacement detecting mode of electrostatic moving element, displacement detecting portion 6 to adopt the electrostatic capacitance detection mode to be illustrated to moving element, but the present invention is defined in this, for example, moving element adopts piezoelectric element, and the displacement detecting mode utilizes this piezoelectric effect also passable.
(embodiment 2)
With reference to Fig. 4～5, the 2nd embodiment according to microactrator of the present invention is described.Fig. 4 is the summary pie graph of microactrator in the present embodiment.
The microactrator of present embodiment is for movable part 4, displacement detecting portion 6, switching part 7, I/F portion 10, displacement of targets configuration part 11, displacement detecting control part 14, has and the same formation of formation of explanation in embodiment 1.With embodiment 1 different part is the formation of control part 50.In the present embodiment, control part 50 utilizes the output of displacement detecting portion 6, and moving element A1～An is carried out intermittent closed-loop control.
Control part 50 comprises voltage instruction portion 51, and voltage instruction portion 51 comprises servocontrol portion 52 and magnitude of voltage maintaining part 53.
Servocontrol portion 52 imports the difference of displacement of targets configuration part 11 and displacement detecting portion 6 as error signal, comprise the PID controller for the control characteristic that keeps expecting, as this control output, gives magnitude of voltage V
L, V
RCommand value, carry out closed-loop control for selected moving element Ai.In addition, servocontrol portion 52 when the value of error signal and its time differential value under the situation below the setting, judge above-mentioned control convergence, end is to the closed-loop control of moving element Ai, when switching to open loop control, carry out closed-loop control for next moving element Ai+1.In more detail, if judged the control convergence, servocontrol portion 52 carves at this moment with magnitude of voltage V
L, V
RCommand value output to magnitude of voltage maintaining part 53.Magnitude of voltage maintaining part 53 is with this magnitude of voltage V
L, V
RCommand value as for the command value V of moving element Ai
Li, V
RiKeep, till the new command value of importing for moving element Ai from servocontrol portion 52 again next time, export this command value.Switching part 7 switches to magnitude of voltage maintaining part 53 with the tie point of moving element Ai from displacement detecting portion 6, and the tie point of moving element Ai+1 is switched to displacement detecting portion 6 from magnitude of voltage maintaining part 53.
Action for the microactrator of above such formation describes with reference to Fig. 5.Fig. 5 is the process flow diagram of closed-loop control at the intermittence program of microactrator in the present embodiment.
At first, make i=1 (step 60), select the 1st moving element A1 as the moving element that carries out closed-loop control.Switching part 7 is with moving element Ai link to each other with displacement detecting portion 6 (step 61).At this moment, the whole moving elements outside the Ai link to each other with magnitude of voltage maintaining part 53, are controlled by open loop based on this output valve.
The control magnitude of voltage V of moving element Ai
L, V
RThe initial value V that adopts the magnitude of voltage maintaining part to keep for 53 last time
Li, V
RiValue (step 62).The displacement of moving element Ai detects in displacement detecting portion 6, to allow this detect the consistent mode of displacement of targets amount of displacement and 11 outputs of displacement of targets configuration part, servocontrol portion 52 is carried out closed-loop control (step 63).
When the absolute value of the error signal that detects displacement and displacement of targets amount is setting α, and the time diffusion value of error signal
Absolute value under the situation below the setting β, control convergence (step 64) is judged by servocontrol portion 52, servocontrol portion 52 carves at this moment with magnitude of voltage V
L, V
RCommand value to magnitude of voltage maintaining part 53 output.Magnitude of voltage maintaining part 53 is with this magnitude of voltage V
L, V
R, command value as for the command value V of moving element Ai
Li, V
RiKeep (step 65).In addition, switching part 7 switches to magnitude of voltage maintaining part 53 (step 66) with the tie point of moving element Ai from displacement detecting portion 6.Thus, from the finishing switching of closed-loop control, move on to the closed-loop control (step 67) of next moving element Ai+1 for moving element Ai to open loop control.If the closed-loop control of n moving element An finishes (step 68), intermittently the closed-loop control program is carried out once circulation.
This intermittently closed-loop control program under the situation that the output valve of displacement of targets configuration part 11 is updated, must be performed at least, moving element A1～An is controlled as desired appearance.It is also passable perhaps to carry out this program usually termly.
Microactrator according to the such present embodiment of above explanation, switching part 7 switches to a plurality of moving elements with 1 displacement detecting portion 6 and servocontrol portion 52, carry out closed-loop control when making it touring, because control convergent moving element keeps the open loop control of this state, even so comprise the actuator of a plurality of moving elements, quantity for the detection signal generator that carries out displacement detecting, amplifier, A/D converter etc. is reduced, can cut down circuit scale, cut down chip cost.
(embodiment 3)
With reference to Fig. 6～7, the 3rd embodiment according to microactrator of the present invention is described.Fig. 6 is the summary pie graph of microactrator in the present embodiment.
The microactrator of present embodiment, for movable part 4, I/F portion 10, displacement of targets configuration part 11, displacement detecting control part the 14, the 1st driving voltage generating unit the 20, the 1st high-frequency signal generating unit the 21, the 2nd driving voltage generating unit the 22, the 2nd high-frequency signal generating unit 23, operational amplifier 24, capacitor 25, MOS transistor 26, amplifier 27, AD transducer 28, the same formation of formation that has and in embodiment 2, illustrate.
With embodiment 2 different parts are formations of switching part 70, displacement detecting portion 71, control part 75.In the present embodiment,, add a formation that only from the displacement detecting signal, extracts the signal of frequency f, can alleviate because the driving voltage V shown in the 2nd on the right of (formula 1) for displacement detecting portion 71
L, V
RVariation
The skew that brings improves the precision of closed-loop control.In addition, after adopting the closed-loop control convergence by servocontrol portion 77, switching part 79 cut-outs and moving element Ai are connected, with terminal T
Li, T
Ri, T
PiRemain on the formation of charges accumulated between electrode as high impedance, sustaining voltage value maintaining part is not carried out simple intermittently closed-loop control.
In switching part 70, disposed each corresponding switch S 1～Sn with moving element A1～An.Each terminal T of switches Si and moving element Ai
Li, T
Ri, T
PiLink to each other, make under the situation of switch connection, each terminal is linked to each other with the driving circuit that comprises displacement detecting portion 71 respectively, make under the situation of switch disconnection, making each terminal is floating state.The connection of each terminal, the switching of disconnection are to carry out simultaneously.
In displacement test section 71,, also comprise oscillator 72, multiplicative operator 73, low-pass filter 74 except the formation of embodiment 2.Oscillator 72 generations and the 1st high-frequency signal generating unit 21 have the AC signal of same frequency f.In addition, to be set to the phase place of the voltage that produces with the 1st high-frequency signal generating unit 21 identical for the phase place of the AC signal that produces of oscillator 72.Multiplying portion 73 is with the output of amplifier 27 and the output multiplication of oscillator 72.Thus, only extract the signal content of the medium frequency f that is output into branch of amplifier 27, the proportional dc voltage of the good fortune of shaking of the signal content of frequency f is output therewith.From the output of multiplicative operator 73 by low-pass filter 74 filtering after, carry out the AD conversion by AD transducer 28.Driving voltage V during thus, by closed-loop control
L, V
RVariation
The drift voltage that produces is lowered, and the displacement detecting precision improves.
Control part 75 comprises voltage instruction portion 76, and voltage instruction portion 76 comprises servocontrol portion 77.
Servocontrol portion 77 imports the difference of displacement of targets configuration part 11 and displacement detecting portion 71 as error signal, export, give magnitude of voltage V as this control
L, V
RCommand value, carry out closed-loop control for the moving element Ai that selects.
In addition, control part 75 comprises clock counter (not shown), with the switches Si of switching part 70 for moment of connecting as starting point, measure the time that each moving element Ai links to each other with servocontrol portion 77.
The time set higher limit τ that the closed-loop control of each moving element Ai is distributed.The value of error signal and its time differential value are below the setting, and the control convergence is if the needed time of closed-loop control reaches more than the higher limit τ closed-loop control that control part 75 finishes for moving element Ai in addition.Higher limit τ is set to the needed sufficient value of control convergence under common state.Higher limit τ is that fixed value is also passable, and the time that its control that is reflected into the moving element till the convergence is experienced determines also passable like that.For example, to the higher limit τ of preceding 1 moving element Ai-1, under the little situation of actual convergence time ti-1, append also passable among the whole or a part of higher limit τ that change moving element Ai over to that make its excess time of τ-ti-1 again.
When being finished by the closed-loop control of 77 couples of moving element Ai of servocontrol portion, switching part 70 disconnects switches Si, makes terminal T
Li, T
Ri, T
PiBe floating state.Thus, C in the electric capacity of moving element Ai formation
Li, C
RiThe quantity of electric charge of middle accumulation is retained as in the very short time necessarily in the disappearance amount that is caused by leakage current, the state the when displacement of moving element Ai is retained as the closed-loop control end.
Switching part 70 makes next switches Si+1 for connecting, and control part 75 carries out closed-loop control for moving element Ai+1.The closed-loop control of moving element is carried out successively according to time series.If the closed-loop control of last moving element An finishes, turn back to initial moving element A1 once more, carry out the closed-loop control in the 2nd cycle.With this cycle cycle length be called the time in frame period.Time in frame period is by the response performance condition that microactrator is tried to achieve, for making owing to capacitor C
Li, C
RiThe conditional decision that the disappearance of the leakage current of middle charges accumulated amount is very little.To each moving element Ai, the higher limit τ of the time of distribution is set and satisfies the condition that this time in frame period should satisfy.For example, under the situation of higher limit τ as fixed value, n τ becomes the time in frame period.But, particularly when closed-loop control with under the digital control situation of carrying out, replace comparison to higher limit τ and elapsed time, undertaken by Measuring Time practically, also can be that the cycle index of closed-loop control is counted and the higher limit of cycle index relatively manages.Cycle index is managed also administrative time indirectly, and this point is also contained in the time management streamlining management process more in itself.
Action for the microactrator of above such formation describes with reference to Fig. 7.Fig. 7 is the process flow diagram of closed-loop control at the intermittence program of microactrator in the present embodiment.
At first, capping value τ is initial value τ 0 (step 80).Initial value τ 0 is the value of the 1/n of time in frame period, is the value that is kept in advance among the ROM.Then, make i=1,, select the 1st moving element A1 (step 81) as the moving element Ai that carries out closed-loop control.
Then, it is connection that switching part 70 makes switches Si, makes moving element Ai link to each other with displacement detecting portion 71 (step 82).At this moment, the whole moving element switches beyond the Ai are for disconnecting.
The control magnitude of voltage V of moving element Ai
L, V
RInitial value be set at the value (step 83) that the output of displacement of targets configuration part 11 is made in transformation component 12 conversion.The displacement of moving element Ai detects in displacement detecting portion 71, and to allow this detect the consistent mode of displacement of targets amount of displacement and 11 outputs of displacement of targets configuration part, servocontrol portion 77 carries out closed-loop control (step 84).
The absolute value that detects the error signal of displacement and displacement of targets amount is setting α, and the time diffusion value of error signal
Absolute value be under the following situation of setting β, control convergence (step 85) is judged by servocontrol portion 77, when not being judged as under the convergent situation, further relatively elapsed time ti and higher limit τ are if ti＜τ then continues closed-loop process (step 86).
When being judged as convergence and elapsed time ti under the situation more than the higher limit, by the closed-loop control end of 77 couples of moving element Ai of servocontrol portion, it is disconnection that switching part 70 makes switches Si, makes terminal T
Li, T
Ri, T
PiBe floating state (step 87).
Then, with excess time, (τ-ti-1) multiply by factor alpha changed the higher limit τ (step 88) to the closed-loop process time of next moving element over to.Factor alpha is to satisfy the value of 0＜α＜1, can prevent that excess time from unrestrictedly being changed over to accumulation.More preferably, factor alpha is that (value 1/N), the degree of influence that changes the result over to of the excess time that 1 time in frame period is former is suppressed at below the setting (1/e) satisfied 0＜α＜exp.
Then, the value of i as increment, is moved on to the closed-loop control (step 89) of moving element Ai+1.Carry out closed-loop control when switching moving element so successively,,, begin the closed-loop control (step 90) of the 1st moving element An as the 2nd time if the closed-loop control of n moving element An of an order finishes.
According to the microactrator of the present embodiment of above explanation, because after finishing as the closed-loop control by servo controller 77, switching part 70 cuts off and being connected of moving element Ai, and makes terminal T
Li, T
Ri, T
PiAs high impedance, remain on the formation of charges accumulated between electrode, so can go the rounds the intermittent closed-loop control of a plurality of moving elements with simple formation.
In addition and since the time set that the closed-loop control of each moving element is distributed higher limit τ, do not rely on the convergence result of closed-loop control, can guarantee time in frame period as microactrator.
In addition, because such decision of time of making this higher limit τ can reflect that the control of moving element hereto experiences, so can make guaranteeing with the raising of closed-loop control precision and depositing of time in frame period.
(embodiment 4)
With reference to Fig. 8～10, the 4th embodiment according to microactrator of the present invention is described.The microactrator of present embodiment is the electrostatic actuator of carrying out knee-action and 2 tilting actions, can be applicable in the deformable mirror that compensate for optical uses.
Fig. 8 is the exploded perspective view of microactrator in the present embodiment.Illustrate the enlarged drawing of 1 tiny mirror unit herein.1 tiny mirror unit is by separate driven 3 groups of displacements that moving element is given 3DOF, and thus, knee-action and 2 tilting action all is possible.Each moving element comprises that yoke and fixed electorde are right.
The tiny mirror unit is 32 * 32, adds up to 1024, by 2 dimension arrays.Is its 3 times 3072 by yoke and fixed electorde to the sum of the moving element that constitutes.
On substrate 100, form driving circuit 100a, form insulation course 101 thereon.On insulation course 101, form the 102 and 3 pairs of fixed electordes 103～105 in bottom.Bottom 102 and fixed electorde 103～105th is formed by the conductive film pattern of aluminium (Al) or polysilicon etc.Fixed electorde 103 comprises the 1st electrode 103L and the 2nd electrode 103R of setting voltage independently of each other.Fixed electorde 104,105 comprises the 1st electrode 104L, 105L and the 2nd electrode 104R, 105R similarly respectively.
The 1st electrode 103L～105L and the 2nd electrode 103R～105R are respectively by linking to each other with the driving circuit 100a that forms on substrate 100 at the via hole (not shown) that forms on the insulation course 101.Driving circuit 100a can will be in 0～30V scope respectively independently voltage be applied on the 1st electrode 103L～105L and the 2nd electrode 103R～105R.This voltage that applies for example can be set as 12 multistage value.
3 yokes 107～109 further are provided with the middle coupling member 111 that links for these yokes 107～109 and tiny mirror 110 respectively by a pair of hinge 106 assemblings.Hinge 106 and bottom 102 engage to one, are conductings on electric.Each bottom 102 links to each other with driving circuit 100a by the via hole (not shown) that forms on insulation course 101.On electric, be separated from each other between the adjacent bottom 102, independently link to each other respectively with driving circuit 100a.
When the 1st electrode 103L is applied under the situation of driving voltage, the part 1 107L of yoke 107 attracted to the 1st electrode 103L one side.Relative therewith, when the 2nd electrode 103R is applied under the situation of driving voltage, part 2 107R attracted to the 2nd electrode 103R one side.Like this, be the center with rotating shaft A, any one direction for CW (clockwise) direction, CCW (counterclockwise) direction can both optionally apply rotating force.
On near the drive point 107c (representing) the terminal of part 1 107L with oblique line, the projection 111a combination of yoke 107 and intermediate linking part spare 111.In addition, near drive point 107c, be provided with the slotted eye 107d that runs through yoke 107.
Intermediate linking part spare 111 comprises 3 projection 111a～111c.The drive point 107c of projection 111a and yoke 107 links to each other, and the drive point 108c of projection 111b and yoke 108 links to each other, and the drive point 109c of projection 111c and yoke 109 links to each other.Therefore, if make yoke 107～109 rotating drive separately, the displacement energy of projection 111a～111c is independently controlled, and the posture of intermediate linking part spare 111 is determined thus.Slotted eye 113a～the 113c that connects intermediate linking part spare 111 is set near projection 111a～111c.
By controlling the driving voltage to the 1st electrode 103L～105L, the 2nd electrode 103R～105R independently, the inclination of the displacement of 110 pairs of z directions of tiny mirror, x axle periphery, the inclination of y axle periphery are driven on positive and negative both direction.
Then illustrate that with reference to Fig. 9 driving circuit 100a's is detailed.Fig. 9 is the summary pie graph of the driving circuit 100a of microactrator in the present embodiment.As by yoke and 2 each moving element Ai that fixed electorde constitutes, j is also together put down in writing.Subscript i and j represent in the 2 dimension arrays of moving element number number of row and column separately.Because constitute 1 tiny mirror unit by 3 moving elements, so that the value of j with per 3 corresponding as dividing unit with 1 tiny mirror.For example, A1,1～A1, the 3rd, in order to make 3 moving elements of identical tiny mirror action.Because the tiny mirror unit is 32 * 32 a array, so i is the natural number till 1～32, j is the natural number till 1～96.
Each moving element Ai, j have connected 6 MOS transistor that switch is used.These MOS transistor are enhancement mode, are H then for conducting, if for L then for ending if make gate voltage.In order by each MOS transistor the loss of voltage to be reduced, gate voltage adopts the voltage that boosts by the booster circuit (not shown).
Among these, 3 MOS transistor of below are used to moving element Ai, when j carries out open loop control, are H if make driving with word line WDi, then drive and use bit line BDj
L, BDj
R, BDj
PWith moving element Ai, the 1st electrode of j, the 2nd electrode, yoke link to each other respectively.
In addition, 3 MOS transistor of top are used to detect moving element Ai, the displacement of j, and during the concerning of correction voltage and displacement, to detect with word line WSi be H if make, then detection bit line BSj
L, BSj
R, BSj
PWith moving element Ai, the 1st electrode of j, the 2nd electrode, yoke link to each other respectively.
Drive with word line WD1～WD32, detect and use word line WS1～WS32 to link to each other, have only according to the selected word line of address signal Adr1 to be changed to H from switch control portion 121 with row decoder 120.Row decoder 120 adopts multiplexer to constitute.
Signal flow during at first, according to the open loop control action is to continuing constituting explanation.
I/F portion 122 and outside carrying out about the order of control and the exchange of data.In the data that from the data of outside input, comprise the corrugated shape that should form about deformable mirror.This corrugated shape data as in each coordinate position in the xy plane for example to the displacement data of z direction or as being endowed according to the polynomial corrugated of Zernike model coefficient data.These data also can transmit the load compression transmission in order to alleviate.Consider to have with the corrugated shape with frame separately compress mode in the frame of compression, obtain with the interframe compress mode of the difference value of the corrugated shape of last time, will be according to the data of dual mode compression in the mutual mode that transmits of each number in accordance with regulations.Perhaps in simpler formation, from the multiple corrugated shape of login in advance, it is also passable to choose desired corrugated shape.In such cases, the data from the outside input are login numbers of corrugated shape.
Displacement of targets configuration part 123 produces and gives each moving element Ai, the displacement of targets data Zi of the displacement of targets of j, j based on the output from I/F portion 122.Each displacement of targets data Zi, j are 20 the data of amounting to 12 portions of number of expression i, j and 8 portions that the size of displacement of targets is shown with 256 segment tables till-128～127.When displacement of targets configuration part 123 at first increased the value of j, with each displacement of targets data Zi, j outputed to transformation component 124 singly., the value of j increases i if reaching maximal value 96.Promptly the serial number of Shu Chu displacement of targets data is Z
1,1, Z
1,2..., Z
1,96, Z
2,1, Z
2,2...
Transformation component 124 comprises that j gives as the address if with displacement of targets data Zi, the voltage instruction data Di that output is corresponding therewith, the map table of j.Voltage instruction data Di, j are 11 bit data of giving 2048 sections value till-1024～1023, and most significant digit is represented positive and negative.Be that most significant digit is represented as driving moving element Ai, among the 1st electrode of the fixed electorde of j, the 2nd electrode one.This map table is made in correction unit 134, is kept in the recordable memory in the transformation component 124.Voltage instruction data Di, j is given shift register 125 by a ground.If to the voltage instruction data Di of shift register 125, the transmission of j finishes, and then transmits next moving element Ai immediately, the voltage instruction data Di of j+1, j+ 1.
The voltage instruction data Di that shift register 125 will send from transformation component 124, j transmits on a ground successively.With moving element Ai, 1～Ai, the voltage instruction data Di of 96 correspondences, 1～Di in the moment that the transmission till 96 finishes, gives strobe signal Stb from switch control portion 121 to latch 126, at this moment, voltage instruction data Di in the shift register 125,1～Di, 96 are kept in the latch 126 simultaneously.The transfer rate of shift register 125 is 16.9MHz, and 11 * 96 data are transmitted with 62.5 μ s.After data in latch 126 were transmitted, shift register 125 transmitted the moving element Ai+1 of next line, 1～Ai+1,96 data at once.That is, latch 126 receives strobe signal Stb with about 62.5 μ s cycles, and these about 62.5 μ s are equivalent to moving element Ai, 1～Ai, and 96 apply the time of voltage.
The voltage instruction data Di that in latch 126, preserves, 1～Di, the 96th, by 96 DA converters 127 and switch 128 each, be transformed to each moving element Ai, the driving voltage that the fixed electorde of j applies.Herein, with moving element Ai, the DA converter 127a of 1 correspondence and switch 128a are that example describes, other 95 DA converters and switch also have same formation.
DA converter 127a is 11 voltage instruction data Di of input, and 1 low 10, output is corresponding to 10 DA converters of the driving voltage of 0～30V range size.
The voltage instruction data Di that switch 128a input is 11,1 most significant digit if the value of this most significant digit is 0, will drives and use bit line BD
1LLink to each other with earthing potential, will drive and use bit line BD
1RLink to each other with the output of DA converter 127a.In addition, if the value of most significant digit is 1, will drives and use bit line BD
1LLink to each other with the output of DA converter 127a, will drive and use bit line BD
1RLink to each other with earthing potential.Thus, moving element Ai, 1 displacement of targets be on the occasion of situation under, the output of DA converter 127a links to each other with the 2nd electrode side, under the situation for negative value, links to each other with the 1st electrode side, moving element becomes possibility to positive negative direction inclination activity control.
Like this, for whole drivings bit line BD of 96 couples
1L, BD
1R, switch 128 selects either party to apply driving voltage from each DA converter 127.
Meanwhile, to give and only make the capable driving of i be the such address signal Adr1 of H with word line WDi to 121 pairs of row decoders 120 of switch control portion.If driving with word line WDi is H, moving element Ai then, 1～Ai, 96 respectively with driving bit line BD
1L, BD
1R, BD
1PConducting becomes the open loop control of carrying out corresponding to the displacement of targets amount.Such as already explained, to moving element Ai, 1～Ai, 96 times that apply driving voltage were 62.5 μ s.On the other hand, moving element Ai, the 1 subresonance frequency of j is 70～100kHz, gets its inverse, the response time of obtaining is about 10～14 μ s.Like this, because the time set that moving element is applied driving voltage is for also will very big value than response time of moving element, very till the stable status, it is possible being continuously applied driving voltage up to the displacement of moving element.Thus, prevent to apply the generation of variation in voltage between the displacement electrodes of the moving element after the end, improve the displacement accuracy of the moving element in open loop control along with driving voltage.
When open loop is controlled, be the cycle with 62.5 μ s like this, increase the value of i, give moving element Ai of each row, 1～Ai, 96 desired displacements.The whole moving elements of 32 row carry out open loop, and to control the needed time be 2ms, and this becomes the time in frame period.
The flow direction of the signal during then, along corrective action continues constituting explanation.Corrective action be carry out when power initiation etc., the flow process of corrective action that it is basic and explanation same in embodiment 1.Be to remove with the key distinction of embodiment 1 because the drift of the stray capacitance of wiring etc., improve the output voltage of position detection accuracy and DA converter 131 and the differential input of displacement test section 133 is applied bias voltage V
ADo not need the output born.
Voltage instruction portion 130 produces the voltage instruction value of 2 passages, when this frequency about with 1～10MHz is switched, gives DA converter 131a, 131b with passage output separately.Thus, DA converter section 131a is with output voltage V
L+ V
A(1+sin (2 π ft)) output, DA converter 131b is with output voltage V
R+ V
A(1-sin (2 π ft)) output.In fact, this amplitude V
A, frequency f the waveform of AC voltage composition, compare with sine wave, square wave is better.When corrective action, voltage instruction portion 130 makes V substantially
AValue be certain, making becomes driving voltage V
L, V
RAmong one be 0V, another multistage is changed.This is to add bias voltage V on the formation that illustrates in embodiment 1
AFormation, the output voltage of DA converter 131a, 131b be generally on the occasion of.
Switching part 132 is according to the address signal Adr2 of switch control portion 121, with the detection bit line BSj of i row
L, BSj
R, BSj
PLink to each other with DA converter 131a, 131b, displacement detecting portion 133 respectively.
In addition, row decoder 120 makes the capable detection of i word line WS according to the address signal Adr1 of switch control portion 121
iBe H.Thus, detection bit line BSj
L, BSj
R, BSj
PWith moving element Ai, the 1st electrode of j, the 2nd electrode, yoke link to each other respectively.Like this, 1 moving element Ai of selection, the 1st electrode of j, the 2nd electrode, yoke link to each other with DA converter 131a, 131b, displacement detecting portion 133 respectively.
The basic comprising of displacement detecting portion 133 is identical with the displacement detecting portion 71 of explanation in embodiment 3, but adopts the positive input employing at initial differential amplifier 133a to apply bias voltage V
AFormation.Thus, compensate the bias voltage V that gives by DA converter 131
A, make moving element Ai, the same when the relation maintenance of each potential difference (PD) between the 1st electrode of j, the 2nd electrode, yoke is controlled with open loop, prevent the decline of correction accuracy.
The voltage instruction value of correction unit 134 input voltage instruction departments 130 outputs and the moving element Ai of displacement detecting portion 133 outputs, the displacement detecting result of j makes the corresponding relation of voltage instruction value and displacement.These corresponding relations are removed measuring error by the curve of approximation match of prescribed form, are stored in the map table of transformation component 124 with the form of interpolation.
Action for the microactrator of above such formation describes with reference to Figure 10.Figure 10 is the process flow diagram of the corrective action program of microactrator in the present embodiment.
At first, set j=1 (step 140), switching part 132 is with the detection bit line BSj of j row
L, BSj
R, BSj
PLink to each other with DA converter 131a, 131b, displacement detecting portion 133 respectively (step 141).Then, set i=1 (step 142), with moving element Ai, j is chosen as the object of displacement detecting.Voltage instruction portion 130 is set at minimum value Dmin (step 143) with voltage instruction value D.At this moment, driving voltage V
R, V
LSize be set at V
R=0V, V
L=30V, both poor V
R-V
LFor minimum voltage (30V).In the explanation afterwards, voltage instruction value D is under the situation of negative value, makes V
R=0V, V
LBe set under, D is positive situation and make V
L=0V, V
RBe set on the occasion of.It is such just as already explained to be used for the overlapping therewith reason of the high-frequency signal of displacement detecting.
At moving element Ai, before the displacement detecting of j, switch control portion 121 is set at L with whole detections with bit line WS1～WS32, makes whole moving element A1, j～A32, j and detection bit line BSj
L, BSj
R, BSj
PConnection disconnect (step 144).The output of the displacement detecting portion 133 of this moment, correction unit 134 is stored (step 145) with it as off-set value Z0 (D).Because be cut off with being connected of moving element, off-set value Z0 (D) expression is because the error percentage that the stray capacitance of wiring and the influence of driving voltage etc. bring.Also have, this step 144,145 operation are only carried out under the situation of i=1.
Then, making detection is H with bit line WSi, moving element Ai, j and detection bit line BSj
L, BSj
R, BSj
PLink to each other (step 146).Displacement Z ' before the output of the displacement detecting portion 133 of this moment is revised as correction unit 134 (D) stores (step 147).Correction unit 134 (D) calculates revised displacement Z (D) and storage (step 148) with off-set value Z0 (D) from revising preceding displacement Z '.Usually, make Z (D)=Z ' (D)-Z0 (D) gets final product, but it is also passable for example to utilize other the correction formula that obtains by experiment to carry out offset correction.
Then, make voltage instruction value D only increase setting (step 149), till D reaches maximal value Dmax (step 150), repeat the measurement of displacement Z (D).Thus, in correction unit 134, accumulated measurement result for the displacement Z (D) of multistage D value.Correction unit 134 is removed measuring error with this approximate function match with regulation, when further utilizing this approximate function to insert, obtains 11 the corresponding voltage instruction value D of each value with 8 displacement Z.Represent moving element Ai by adding thereon, 12 bit data of number number of j, for moving element Ai, the map table of the displacement of j and voltage instruction value D has just been made (step 151).
Then, make i increase (step 152), for 32 moving element A1 of same j row, j～A32, j similarly make the map table (step 153) of displacement Z and voltage instruction value D.
Then, make j increase (step 154), for whole map tables (step 155) of making displacement Z and voltage instruction value D equally of 96 moving elements that are listed as.
Figure 11 (a) and (b) be the curve map of the corresponding relation of voltage instruction value D and displacement in the some moving elements of expression.Figure 11 (a) describes the data about offset correction.Among the figure * data point that mark is represented is the off-set value Z0 (D) that measures, the data point that the Δ mark is described be before the correction of measuring displacement Z ' (D).The data point that zero mark is represented be utilize Z (D)=Z ' (D)-revised displacement Z (D) that the relation of Z0 (D) is calculated.
When making voltage instruction value D herein, obtain displacement Z (D) corresponding to each voltage instruction value D with 13 sections variations.The increment of each section of voltage instruction value (D) is not certain.For the displacement Z ' variable quantity (D) of voltage instruction value D, big more near Dmax and Dmin voltage instruction value D more.Therefore, voltage instruction value D is more little near Dmax and its increment of Dmin more.Like this, by the nonlinear relation of considering to exist between voltage instruction value D and displacement Z ' are (D), the increment of decision voltage instruction value D can make displacement Z ' increment (D) roughly certain.
In Figure 11 (b), represent with the displacement Z (D) after the offset correction of approximate function match with solid line.The approximate function of Shi Yonging is 2 rank function Z (D)=α D herein
2+ β D+ γ.In each of the quadrant of the quadrant of D＞0 and D＜0, obtaining and making error of fitting is minimum α, β, the coefficient value of γ.In Figure 11 (b), for ease of with reference to also having represented voltage instruction value D before the correction that dotted line is represented and the corresponding relation of displacement Z.
As described above, utilize j and detection bit line BSj with moving element Ai
L, BSj
R, BSj
PDeng the state that links to each other of wiring under the displacement Z that obtains and with moving element Ai, the off-set value ZO that obtains under the state that j separates from these wirings revises.Therefore, the influence of the skew that can remove because the stray capacitance of wiring etc. causes improves moving element Ai, the position detection accuracy of j.
Also have, in the present embodiment, switch when connecting singly, carried out the displacement detecting of moving element, but also can comprise manyly, carry out the displacement detecting of a plurality of moving elements simultaneously being equivalent to the formation of voltage instruction portion 130, DA converter 131a, 131b and displacement detecting portion 133.Particularly, drive 3 moving elements that belong to 1 tiny mirror unit simultaneously, the displacement of detection each moving element this moment is proofreaied and correct and owing to also can be compensated these control under the situation of the displacement that the reception and registration generation of the driving force between moving element is disturbed respectively.In such cases, the map table that correction unit 134 is made has for example moving element A1 if give, 1 displacement (Z1,1), A1,2 displacement (Z1,2), A1,3 displacement (Z1,3) address of 3 such information then becomes to moving element A1,1 voltage instruction value D1, and 1 is output.For voltage instruction value D1,1, if displacement Z1,2, Z1,3 influences that bring are smaller, displacement Z1,2, Z1,3 are adopted high-order getting final product.
(embodiment 5)
With reference to Figure 12, the 5th embodiment according to microactrator of the present invention is described.Figure 12 is the summary pie graph of microactrator in the present embodiment.
The control part 75 of the microactrator of present embodiment has identical formation with control part 75 in the microactrator of embodiment 3.The different piece of the microactrator of the microactrator of present embodiment and embodiment 3 is formations of movable part 160, switching part 161 and displacement detecting portion 162.Below, these formations are described.
In the present embodiment, being used for the movable part 160 of displacement detecting and the wiring formation of switching part 161 is simplified.The float electrode Y of movable part 160
LiDo not link to each other, all ground connection with switching part 161.Therefore, though each switches Si of switching part 161 comprise and fixed electorde E
LiThe switch that links to each other and with fixed electorde E
Ri2 switches of the switch that links to each other, but with float electrode Y
LiThe switch that links to each other is omitted.
Displacement detecting portion 162 comprises as shown in figure 12: high-frequency signal generating unit 21, pull-up resistor 163L, 163R, isolator 164L, 164R, Hi-pass filter 165L, 165R, high frequency phase difference detection portion 166 and AD transformation component 167.
The end of pull-up resistor 163L is called as " the 1st terminal T
L", this 1st terminal T
L, by the switches Si of switching part 161 and the fixed electorde E of moving element Ai
LiLink to each other.Applied drive signal V on the other end of pull-up resistor 163L from the 1st driving voltage generating unit 20
LWith from the high-frequency signal V of high-frequency signal generating unit 21
ASin (2 π ft) with signal V
L+ V
ASin (2 π ft).
Similarly, the end of pull-up resistor 163R is called as " the 2nd terminal T
R", this 2nd terminal T
RBy the switches Si of switching part 161 and the fixed electorde E of moving element Ai
RiLink to each other.Applied drive signal V on the other end of pull-up resistor 163R from the 2nd driving voltage generating unit 22
RWith high-frequency signal V from high-frequency signal generating unit 21
ASin (2 π ft) with signal V
R+ V
ASin (2 π ft).
High-frequency signal V for pull-up resistor 163L, 163R
AThe impedance Z of sin (2 π ft)
0Be mutually identical.Herein, this impedance Z
0Be the pure resistance that does not comprise imaginary part, and be the value that has adopted the internal resistance that comprises the 1st driving voltage generating unit 20 and the 2nd driving voltage generating unit 22.
Impedance Z
0Size be if moving element Ai does not have the capacitor C under the situation of displacement
Li, C
RiEach electrostatic capacitance be C, satisfy 0.5＜2 π fCZ
0＜2 is selecteed like this.For example, be under the situation of 10fF as C, making f is 100MHz, Z
0For 160k Ω is set like this.If in such scope, set impedance Z
0, displacement detecting sensitivity is almost near maximum.
Isolator 164L, 164R respectively with the 1st terminal T
L,, the 2nd terminal T
RLink to each other, carry out impedance conversion.Isolator 164L, 164R are made of the voltage follower that has adopted arithmetical unit.The output of isolator 164L, 164R is respectively via Hi-pass filter 165L, 165R input high frequency phase difference detection portion 166.Hi-pass filter 165L, 165R have sufficient trafficability characteristic for the radio-frequency component of frequency f, for drive signal V
L, V
RThe low-frequency component that comprises has sufficient barrier.
The phase differential of 2 high-frequency signals of input detects in high frequency phase difference detection portion 166, and output is corresponding to the signal of this phase differential.The output of high frequency phase difference detection portion 166 is transformed to numerical data by AD transformation component 167.This numerical data becomes expression capacitor C
Li, C
RiCapacitance difference promptly represent the data of the displacement of moving element Ai.
These isolators 164L, 164R, Hi-pass filter 16L, 165R, high frequency phase difference detection portion 166, AD transformation component 167 are brought into play function as " high-frequency detection portion " in microactrator of the present invention.
If according to instruction, make drive signal V from the 1st driving voltage generating unit 20 from control part 75
LWith from the drive signal V of the 2nd driving voltage generating unit 22
RThe amplitude difference, moving element Ai displacement.According to the capacitor C that produces thereupon
Li, C
RiCapacitance difference, at the 1st above-mentioned terminal T
LWith the 2nd terminal T
RBetween produce the phase differential of the radio-frequency component of frequency f.Therefore, even float electrode Y
LiBe not individually to link to each other with displacement detecting portion 162, the detection of displacement also is possible.
Also have, drive signal has the following frequency of 1 subresonance frequency of moving element Ai.The drive signal of Cai Yonging is a DC voltage in the present embodiment.That is, the size of drive signal means magnitude of voltage in this word.High-frequency signal has the above frequency of 1 subresonance frequency of moving element Ai.
According to the microactrator of the present embodiment of above explanation, displacement detecting portion 162 comprises: high-frequency signal generating unit the 21, the 1st terminal T
LIn with the 1st electrode E
LiThe 1st pull-up resistor 163L, the 2nd terminal T that link to each other
RIn with the 2nd electrode E
RiThe 2nd pull-up resistor 163R that links to each other, with the 1st terminal T
L, and the 2nd terminal T
RThe high-frequency detection portion 164～167 that links to each other.The other end at the 1st pull-up resistor 163L is applied to the 1st drive signal V
LGo up overlapping high-frequency signal V
AThe 1st and signal V that sin (2 π ft) generates
L+ V
ASin (2 π ft) is applied to and the 1st drive signal V at the other end of the 2nd pull-up resistor 163R
LThe 2nd drive signal V with different sizes
RGo up overlapping high-frequency signal V
AThe 2nd and signal V that sin (2 π ft) generates
R+ V
ASin (2 π ft), because high-frequency detection portion 164～167th, at the 1st terminal V
LWith the 2nd terminal V
RBetween detect the such formation of phase differential of high-frequency signal, so there is no need to make float electrode Y
iLink to each other with displacement detecting portion 162 singly, the wiring that can simplify movable part 160 and switching part 161 significantly constitutes.
Further according to the formation of present embodiment, the quantity of high-frequency signal generating unit 21 also is to have only 1 to get final product, and can omit the 2nd high-frequency signal generating unit 23 that makes phase overturn.
In addition, though the pull-up resistor 163L of present embodiment, the impedance of 163R fix, any one of pull-up resistor 163L, the 163R for example impedance of pull-up resistor 163L is variable also passable.In such cases, by making terminal T
LWith terminal T
RBetween the composition of frequency f of differential voltage be 0 to adjust the impedance of pull-up resistor 163L like this, also can detect capacitor C
Li, C
RiCapacitance difference.
Herein, though pull-up resistor 163L, 163R are made of the pure resistance that does not have imaginary part, the present invention is defined in this.Adopt coil and electric capacity etc. to make up separately or with resistance, it is so also passable to make resistance value have imaginary part.Particularly, if utilize the resonant circuit structure, can significantly improve phase-detection sensitivity.
" loaded impedance element " is not limited to " pull-up resistor " in the present embodiment in the microactrator among the present invention, also comprises containing the above-mentioned coil and the loaded impedance of electric capacity.
Replacement detects the high frequency phase difference detection portion 166 of the phase differential of 2 high-frequency signals importing, also can adopt the difference of vibration of 2 high-frequency signals that detect input or the formation of amplitude ratio." high-frequency detection portion " also can be the phase place of 2 high-frequency signals relatively importing and/or the formation arbitrarily of amplitude in the microactrator of the present invention.
Also have, constitute and the difference of general impedance bridge circuit etc. remarks additionally once more for the circuit of the displacement detecting portion 162 of present embodiment.The feature that the circuit of displacement detecting portion 162 constitutes is only to the high-frequency signal symmetry, and, asymmetric to low frequency signal.The 1st driving voltage generating unit 20 that promptly constitutes in impedance bridge circuit can produce different driving voltage mutually with the 2nd driving voltage generating unit 22.Constitute by having asymmetrical circuit for such low frequency signal, when making the float electrode displacement of moving element Ai, detecting its displacement becomes possibility.On the other hand, because be to adopt the circuit of symmetry to constitute, so utilize terminal T for high-frequency signal
LWith terminal T
RDifferential wave, can precision detect capacitor C well
Li, C
RiThe small electric tolerance.
(enforcement side is 6)
With reference to 6th embodiment of Figure 13 and Figure 14 explanation according to microactrator of the present invention.Figure 13 is the summary pie graph of microactrator in the present embodiment.
Moving element Ai in the microactrator of present embodiment, j, I/F portion 122 and displacement of targets configuration part 123 have the same formation of formation in the microactrator with embodiment 4.In addition, displacement detecting portion 170 is with the 162 a plurality of formations arranged side by side of the displacement detecting portion in the microactrator of embodiment 5.
The different part of formation of the formation of present embodiment and embodiment 4,5 is with voltage instruction value Di, and j is transformed to driving voltage V
I, j, L, V
I, j, RThe non-linear DA converter 176 of Shi Caiyong, complementary drive voltages V
I, j, L, V
I, j, RNon-linear with the displacement of moving element makes voltage instruction value Di, and the relation of the displacement of j and moving element is roughly linearity.Thus, not only can be reduced to the terrible necessary voltage instruction value Di of resolution to displacement, the figure place of j can also significantly reduce correction unit 178 with approximate function match voltage instruction value Di, the operand the during corresponding relation of j and moving element.
Each moving element Ai has connected 2 MOS transistor that switch is used among the j, be H if make word line Wi, then bit line Bj
L, Bj
RRespectively with moving element Ai, the 1st electrode of j, the 2nd electrode conduction.
Word line W1～W32 links to each other with row decoder 171, and having only the word line of selecting according to the address signal Adr1 from switch control portion 172 is H.
Transformation component 173, shift register 174, the voltage instruction value Di of latch 175 except handling, the figure place of j is beyond 9, and is identical with transformation component 124, shift register 125, the latch 126 of explanation in embodiment 4.Because the voltage instruction value that transformation component 124, shift register 125, latch 126 are handled is 11, so in the present embodiment in contrast to this, be that 2 formations that precision is thicker are arranged, but because by adopting non-linear DA converter 176 described later to make voltage instruction value Di, the relation of the displacement of j and moving element is roughly linearity, so can obtain same result as the resolution of the displacement of moving element.According to 9 voltage instruction value Di, the value of the most significant digit of j, expression moving element Ai, which of the 1st electrode, the 2nd electrode the driven fixed electorde of j be, also the content with explanation in embodiment 4 is identical for this point.The transfer rate of shift register 171 is 13.8MHz, and 9 * 96 data transmit with 62.5 μ s.
The voltage instruction value Di that in latch 175, preserves, 1～Di, 96 are transformed at each moving element Ai the driving voltage V that applies on each fixed electorde of j by 96 non-linear DA converters 176
I, j, L, V
I, j, RNon-linear DA converter 176 is to according to each voltage instruction value Di, the bit line Bj that the most significant digit of j is selected
L, Bj
RAny one output and each voltage instruction value Di, the driving voltage of the value correspondence of the least-significant byte of j.Give the nonlinear corresponding relation of a certain regulation in the value of this least-significant byte and the size of driving voltage.This nonlinear corresponding relation is set to displacement non-linear of just complementary drive voltages and moving element, so that voltage instruction value Di, the pass of the displacement of j and moving element is that linear mode is provided with.Detailed back narration for this non-linear DA converter 176.
Capable word line Wi is H if row decoder 171 only makes i, each moving element Ai, j and bit line B
IL, B
IRConducting, according to voltage instruction value Di, j, moving element Ai, the displacement of j is controlled by open loop.
When corrective action,, when the j multistage switches, carry out displacement detecting by displacement detecting portion 170 with this voltage instruction value Di.The output of displacement detecting portion 170 is transfused to correction unit 178 and voltage instruction value Di, and j is corresponding, makes correction chart.This action and comprise offset correction, in embodiment 4 explanation action basic identical.Be when the time with the different of embodiment 4, use 1 rank function D (Z)=α Z+ β with the approximate function match.
Below, utilize Figure 14 that 1 rank approximation to function action of the formation and the correction unit 178 of non-linear DA converter 176 is described.
Figure 14 (a) is the summary pie graph of non-linear DA converter 176.This sentences 1 non-linear DA converter 176a is that example describes, and other 95 also have same formation.Also have,, omitted the Di of the corresponding relation of expression and moving element in order to simplify, the subscript i of j, j etc., voltage instruction value with D, at the driving voltage of the 1st electrode and the output of the 2nd electrode with V
L, V
R, bit line is with B
L, B
RDescribe.
Non-linear DA converter 176 adopts and makes the current potential at the resistance R 1～Rn-1 two ends that are connected in series be respectively potential minimum V1 and maximum potential Vn, produces the voltage V1～Vn of the n value that comprises the medium voltage that obtains by electric resistance partial pressure.Then, suitably select the formation of any one output among this n value current potential V1～Vn by selector switch 180.Herein, potential minimum V1 is an earthing potential.In addition, because the position precision of non-linear DA converter 176a is 8, so the value of n is 256.
The voltage instruction value that selector switch 180 inputs are 9 is with corresponding therewith driving voltage V
L, V
ROutput to bit line B respectively
L, B
RIf the most significant digit of voltage instruction value D is 0, driving voltage V
LSelect potential minimum V1, driving voltage V
RSelect any one current potential of the V1～Vn corresponding with the least-significant byte of voltage instruction value D.In addition, if most significant digit is 1, driving voltage V
LSelect any one current potential of the V1～Vn corresponding, driving voltage V with the least-significant byte of voltage instruction value D
RSelect potential minimum V1.In the explanation afterwards, the symbol of definition voltage instruction value D in the most significant digit of voltage instruction value D be under 0 the situation for just, most significant digit is for bearing under 1 the situation.In addition, definition driving voltage V is V=V
R-V
LAnd voltage instruction value D similarly gives positive and negative symbol.
The resistance value of setting resistance R 1～Rn-1 comprises mutually different at least value, by suitably setting this resistance value, can realize non-linear arbitrarily.More particularly, the terminal that will link to each other with potential minimum V1 is called R1 near the resistance of a side, below be called in order R2, R3 ... Rn-1, make its resistance value have R1＞R2＞R3＞... such relation that number diminishes in order that＞Rn-1 is such.By carrying out such setting, carry out current potential Vi (under the big more situation of the value of I=2～n), the increase Vi-Vi-1 of current potential such setting that diminishes more.Promptly the absolute value with driving voltage V is big more, and the mode that becomes more little for the recruitment of the increase driving voltage V of voltage instruction value D is provided with.
Owing between the displacement Z of driving voltage V and moving element, exist the absolute value of driving voltage V big more, the big relation of increase quantitative change for the increase displacement Z of driving voltage, by giving the nonlinear characteristic of above-mentioned such DA converter 176, the nonlinear characteristic of the driving voltage V and the displacement Z of moving element can be compensated, the approaching linearity of relation of the displacement Z ' of voltage instruction value D and moving element can be made.
More preferably so that the function V (D) of voltage instruction value D and driving voltage V is satisfied | V|=k|D|
1/2The mode of the relation of (k is a constant), the resistance value of setting resistance R 1～Rn.
Figure 14 (b) is for the curve map of the corresponding relation of voltage instruction value D and displacement Z in correction unit 178 is described.
The voltage instruction value D of the non-linear DA converter 176 of the curve (A) of upper right quarter expression and the characteristic function V (D) of driving voltage V in Figure 14 (b).Such just as already explained, give | V|=k|D|
1/2The relation of (k is a constant).More correctly, set to satisfy when voltage instruction value D be on the occasion of situation under, V=kD
1/2, voltage instruction value D is under the situation of negative value, V=-k is (D)
1/2, such nonlinear relationship.Because this characteristic is the resistance R 1～Rn-1 decision by non-linear DA converter 176, so be can not be by the fixing relation of outside operation change.
In Figure 14 (b), in the curve (B) of upper left quarter, the driving voltage V of some moving element A1 and the characteristic function Z1 (V) of displacement Z have been represented with solid line.In addition, the characteristic function Z2 (V) of the driving voltage V of other moving element A2 and displacement Z dots.Just the characteristic of each moving element is not scattered for this moving element A1 and A2 different, also is included in the same moving element, because with the different characteristic variations of bringing of long-time variation and environmental baseline.In this figure,, in fact there is more characteristic function though only drawn 2 different characteristic functions.Because this characteristic also is by the decision of the state of moving element, so also be can not be by the fixing relation of outside operation change.
In Figure 14 (b) in the curve (C) of lower left, owing to proofreaied and correct the characteristic of this moving element A1, A2, so drawn the correction function D1 (Z) that correction unit 178 is made, D2 (Z).Correction function D1 (Z) is the displacement Z of expression moving element A1 and the relation of voltage instruction value D, represents with solid line in the drawings.Correction function D2 (Z) is the displacement Z of expression moving element A2 and the relation of voltage instruction value D, dots in the drawings.These correction functions D1 (Z), D2 (Z) become can be according to the corrective action relation of new settings more at random.
To in corrective action, when multistage changes voltage instruction value D, detect displacement Z, from then on the process made till the correction function D (Z) of result describes.
At first, as in the curve A of Figure 14 (b) with 5 circle-dot modes draw, select 5 sections voltage instruction value D.According to the characteristic function V (D) of non-linear DA converter 176, export 5 sections driving voltage V.
Then, in the curve B of Figure 14 (b), according to this driving voltage D, moving element A1 adopts at characteristic function Z1 (V) and goes up the displacement Z that represents with 5 round dots.Similarly, moving element A2 adopts at characteristic function Z2 (V) and goes up the displacement Z that represents with 5 triangles.The size of these displacements Z is detected by displacement detecting portion 170.
Then, in the curve C of Figure 14 (b), mated with correction function D (Z) by the displacement Z of displacement detecting portion 170 detections and the relation of voltage instruction value D.
Because compensate nonlinear characteristic Z1 (V), the Z2 (V) of moving element by the nonlinear characteristic V (D) of non-linear DA converter 176, so almost near linear, adopting 1 rank function is possible as the match of approximate function for correction function D1 (Z), D2 (Z).Therefore, just merely do not reduced the exponent number of approximate function, there is no need to divide quadrant to be suitable for yet, can carry out unified operation, the computing of match is carried out extremely simply at whole quadrants according to the positive and negative pairing approximation function of voltage instruction value D and displacement Z.
In addition, adopt as approximate function under the situation of 1 rank function, voltage instruction value D is directly represented as the function D (Z) of displacement Z, be not easy to make precise decreasing especially.The description of this function D (Z) is compared with its inverse function describing Z (D), also is good on the adaptability of the transformation component 173 of necessity when the displacement of targets transform is voltage instruction value D, can carry out more simply about the operation of the conversion of making of map table etc.
Also have, any one of correction function D1 (Z), D2 (Z) all shows and be bordering on linear characteristic might not be certain on mathematics.One of reason that such linearization precision is carried out well is because characteristic function Z1 (V), the Z2 (V) of moving element get shape arbitrarily, but has the character of the variation of a certain tendency.This tendency is meant the value that does not rely on V, and Z1 (V) expression approaches the value of a certain constant times of Z2 (V), and this is the main cause that the characteristic function Z (V) of moving element changes, and is certain reason of variation of elastic constant of bringing the hinge 106 of moving element.The hinge 106 of moving element has linear restoring force like this, in driving force and restoring force are cancelled out each other the system of decision displacement, make non-linear DA converter 176 have non-linear, compensate the non-linear of driving force and displacement, so can access the precision of the linearity between displacement of targets Z and the voltage instruction value D, as illustrating, can calculate correction function D (Z) accurately by simple calculations.
Microactrator according to present embodiment, comprise the non-linear DA converter 176 that voltage instruction value D non-linearly is transformed to driving voltage D, the value of driving voltage V is big more, by reducing to be provided with recruitment corresponding to the drive signal V of the recruitment of voltage instruction value D, the displacement Z's of complementary drive voltages V and moving element is non-linear, can make the relation of the displacement Z of voltage instruction value D and moving element approach linearity.Thus, the figure place that is reduced to the necessary voltage instruction value D of terrible resolution to displacement becomes possibility, can carry out the reduction of circuit scale and data transfer rate.
In addition, because correction unit 178 is approximate with the correction function D (Z) of 1 rank function with the corresponding relation of the displacement Z of voltage instruction value D and moving element, also there is no need to divide quadrant to be suitable for according to the positive and negative pairing approximation function of voltage instruction value D and displacement Z, can be when all quadrant carries out unified operation, voltage instruction value D is directly represented it is possible as the function D (Z) of displacement Z, can reduce the correction calculation amount significantly.
As described above, according to the present invention, when making the moving element displacement according to the drive signal of drive division output, detect its displacement by displacement detecting portion, because correction unit is proofreaied and correct the corresponding relation of displacement and drive signal, so do not need outside deviation meter, when can detect the displacement of indivedual moving elements extremely simply, the variation of the moving element characteristic that can bring with the environmental change with long-time variation and temperature etc. is corresponding.
In addition, since switching part make drive division and/or displacement detecting portion and a plurality of moving elements each optionally be connected, even so comprised the microactrator of a plurality of moving elements, also can cut down and be used for displacement detecting circuit, can reduce the cost of chip.
In addition, be used for deformable mirror by the microactrator that will have so own displacement detection function, can be with simple formation, carry out to reliability photocontrol high, that light loss is little with long-time variation, environmental change.
(in industrial possibility of its application)
Microactrator of the present invention just is not applied to deformable mirror, can also be applicable to high-frequency circuit purposes such as relay switch and tunable capacitor, perhaps the various uses of the fluid purposes of micropump etc.
Claims (32)
1, a kind of microactrator is characterized in that, comprising:
Substrate;
Moving element, it is supported on the described substrate movablely;
Drive division, its output are used to allow the drive signal of described moving element displacement;
Transformation component, it keeps the displacement of described moving element and the corresponding relation between the described drive signal;
Displacement detecting portion, it detects in the displacement of having given the described moving element under the described driving status signal; With
Correction unit, the corresponding relation that it utilizes the described transformation component of output calibration of described drive signal and described displacement detecting portion to keep.
2, microactrator according to claim 1 is characterized in that,
Described moving element is the moving element of electrostatic, is included on the described substrate fixing fixed electorde and the float electrode of facing mutually with described fixed electorde;
The displacement of described moving element detects according to the variation of the electrostatic capacitance between described fixed electorde and described float electrode in described displacement detecting portion.
3, according to claim 1 or 2 described microactrators, it is characterized in that,
Described drive division with near the 1 subresonance frequency of described moving element or the low frequency signal below it export as described drive signal;
Described displacement detecting portion overlaps the high-frequency signal more than the 1 subresonance frequency of described moving element on the described drive signal.
4, microactrator according to claim 3 is characterized in that,
Described drive division is exported substantial dc voltage as described drive signal.
5, microactrator according to claim 4 is characterized in that,
Described drive division is exported the described dc voltage of multistage as described drive signal;
The displacement of described moving element detects in described displacement detecting portion in each section of described multistage;
Described correction unit is approximate with the approximate function of prescribed form with the output of the dc voltage of described each section and described displacement detecting portion.
6, microactrator according to claim 3 is characterized in that,
Described drive division will have the low frequency signal of multistage frequency and export as described drive signal;
The displacement that adds the described moving element that shakes detects in described displacement detecting portion;
Described correction unit is corresponding with the output of displacement detecting portion with described drive signal, calculates the amplitude response or the phase response of described moving element.
7, according to claim 3 or 6 described microactrators, it is characterized in that,
Described drive division is exported near the low frequency signal the 1 subresonance frequency of described moving element as described drive signal multistage;
The displacement that adds the described moving element that shakes detects in described displacement detecting portion in each section of described multistage;
Described correction unit makes described drive signal corresponding with the output of displacement detecting portion, extracts 1 subresonance frequency of described moving element.
8, according to each described microactrator in the claim 3～7, it is characterized in that,
When increase setting the amplitude of described drive signal, reduce to set the amplitude of the described high-frequency signal that described displacement detecting portion produces.
9, according to each described microactrator in the claim 2～8, it is characterized in that,
The described float electrode of described moving element comprises axle roughly the 1st electric conductivity part and the 2nd electric conductivity part of symmetry in accordance with regulations, and it is supported versatilely to be with described axle that the center can freely tilt, and,
Described fixed electorde comprises the 1st electrode of partly facing mutually by the gap with the 1st electric conductivity of described float electrode and the 2nd electrode of partly facing mutually by the gap with the 2nd electric conductivity of described float electrode;
Described drive division is applying described drive signal between described the 1st electric conductivity part and described the 1st electrode or between described the 2nd electric conductivity part and described the 2nd electrode;
Described displacement detecting portion applies the 1st high-frequency signal on described the 1st electrode, on described the 2nd electrode, apply and described the 1st high-frequency signal same-amplitude and the 2nd opposite high-frequency signal of phase place, detect will described the 1st electric conductivity partly and the voltage of the terminal that partly is electrically connected of described the 2nd electric conductivity.
10, according to each described microactrator in the claim 1～9, it is characterized in that,
The corresponding voltage instruction value of displacement of described transformation component generation and described moving element;
Described drive division comprises the DA converter of output corresponding to the described drive signal of described voltage instruction value;
Described correction unit is proofreaied and correct the corresponding relation between the displacement of described voltage instruction value and described moving element.
11, microactrator according to claim 10 is characterized in that,
Described DA converter section has nonlinear characteristic, and the value of described drive signal is big more, reduces the recruitment of setting the described drive signal corresponding with described voltage instruction value more.
12, microactrator according to claim 11 is characterized in that,
Described correction unit is with the corresponding relation between the displacement of described voltage instruction value of 1 rank approximation to function and described moving element.
13, according to each described microactrator in the claim 1～12, it is characterized in that,
When power initiation, allow described correction unit move.
14, according to each described microactrator in the claim 1～13, it is characterized in that,
Comprise temperature detecting part, when described temperature detecting part detects temperature variation more than the setting, allow described correction unit action.
15, according to each described microactrator in the claim 1～14, it is characterized in that,
Comprise unusual judging part, when its output in described displacement detecting portion surpasses specialized range, judge the unusual of described moving element or described displacement detecting portion.
16, microactrator according to claim 15 is characterized in that,
When described unusual judgement section judges when being unusual, forbid renewal by the described corresponding relation of described correction unit.
17, a kind of microactrator is characterized in that, comprising:
Substrate;
Moving element, it is supported on the described substrate movablely;
Drive division, its output are used to allow the drive signal of described moving element displacement;
Displacement detecting portion, it detects the displacement of described moving element; With
Switching part, it optionally connects described drive division and/or described displacement detecting portion and described a plurality of moving elements each.
18, microactrator according to claim 17 is characterized in that,
Described switching part switches the displacement detecting object of described displacement detecting portion on one side with time series, Yi Bian detect the displacement of each described moving element.
19, according to claim 17 or 18 described microactrators, it is characterized in that,
Comprise closed-loop control portion, it utilizes the output of described displacement detecting portion, the output of the described drive division of closed-loop control.
20, microactrator according to claim 19 is characterized in that,
Comprise that further open loop controls the open loop control part of the output of described drive division, switch described closed-loop control portion and described open loop control part, carry out the control of described moving element with time series.
21, microactrator according to claim 20 is characterized in that,
Described open loop control part comprises the preservation portion of the output of preserving the described drive division of controlling by described closed-loop control portion.
22, microactrator according to claim 19 is characterized in that,
Described moving element is configured to accumulate the electric charge corresponding to described drive signal;
Described switching part switches to the 2nd state that described moving element is kept described electric charge as high impedance with described moving element with the 1st state that described closed-loop control portion links to each other.
23, according to each described microactrator in the claim 19～22, it is characterized in that,
Comprise the counter of the time value that measurement links to each other with described closed-loop control portion about each described moving element and detect the convergent convergence detection portion of described closed-loop control;
Even surpass the set upper limit value from the output of described counter, described convergence detection portion does not detect under the described convergent situation yet, and described switching part cuts off being connected of described moving element and described closed-loop control portion.
24, microactrator according to claim 23 is characterized in that,
The time value that is connected with described closed-loop control portion about described moving element is the cycle index of described closed-loop control portion.
25, microactrator according to claim 23 is characterized in that,
Described convergence detection portion detects described convergence, described switching part switches to the moment of next moving element at the tie point of described closed-loop control portion, when the output of described counter does not reach under the situation of described higher limit, according to the output of described counter, change the higher limit of next moving element.
26, according to each described microactrator in the claim 17～25, it is characterized in that,
Described switching part is with linking to each other with described displacement detecting portion simultaneously more than 2 among described a plurality of moving elements at least.
27, according to each described microactrator in the claim 3～16, it is characterized in that,
To be applied on the both sides of described fixed electorde and described float electrode with the equal above big or small bias voltage of the amplitude of described high-frequency signal.
28, microactrator according to claim 1 is characterized in that,
Comprise switching part, it is set in the wiring path that connects between described drive division and/or described displacement detecting portion and the described moving element, switches between the state of state that connects described wiring path and cut-out;
Described correction unit utilization is in the 1st output of the described displacement detecting portion that obtains under the state that has connected described wiring path and cut off the 2nd output of the described displacement detecting portion that obtains under the state of described wiring path, revises.
29, microactrator according to claim 1 is characterized in that,
Described moving element is included on the described substrate fixing fixed electorde and the float electrode of facing mutually with described fixed electorde;
Described float electrode comprises roughly symmetrical the 1st electric conductivity part and the 2nd electric conductivity part of axle according to the rules, is that the center energy freely tilt supported versatilely with described axle;
Described fixed electorde comprises the 1st electrode of partly facing mutually by the gap with the 1st electric conductivity of described float electrode and the 2nd electrode of partly facing mutually by the gap with the 2nd electric conductivity of described float electrode;
Described drive division is created in the 1st drive signal that described the 1st electrode applies and has size different with described the 1st drive signal and the 2nd drive signal that applies at described the 2nd electrode;
Described displacement detecting portion comprises: the high-frequency signal generating unit of exporting the above high-frequency signal of 1 subresonance frequency of described moving element, the 1st loaded impedance element that links to each other with described the 1st electrode at the 1st terminal, the 2nd loaded impedance element that links to each other with described the 2nd electrode at the 2nd terminal, the high-frequency detection portion that connects described the 1st terminal and described the 2nd terminal, with the terminal of the opposite side of described the 1st terminal of described the 1st loaded impedance element on applied described the 1st drive signal of described high-frequency signal overlapping, with the terminal of the opposite side of described the 2nd terminal of described the 2nd loaded impedance element on applied described the 2nd drive signal of described high-frequency signal overlapping;
The displacement of described moving element detects by the relatively phase place and/or the amplitude of the described high-frequency signal between described the 1st terminal and described the 2nd terminal in described high-frequency detection portion.
30, a kind of deformable mirror is characterized in that,
Comprise each described microactrator in the claim 1～29;
At least a portion at described moving element forms reflection region.
31, a kind of device is characterized in that,
Comprise each described microactrator in the claim 1～29.
32, a kind of driving method is used to drive the microactrator with moving element, it is characterized in that, comprising:
Output is used to allow the step of drive signal of described moving element displacement;
Keep the displacement of described moving element and the step of the corresponding relation between the described drive signal;
Detection is in the step of the displacement of giving the described moving element under the state of described drive signal;
Utilize the output of described drive signal and described displacement detecting portion, the step of proofreading and correct described corresponding relation.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP322247/2002 | 2002-11-06 | ||
| JP2002322247 | 2002-11-06 | ||
| JP352736/2003 | 2003-10-10 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1708449A true CN1708449A (en) | 2005-12-14 |
| CN100405122C CN100405122C (en) | 2008-07-23 |
Family
ID=35581817
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB2003801023104A Expired - Lifetime CN100405122C (en) | 2002-11-06 | 2003-11-05 | Microactuator provided with displacement detection function, and deformable mirror provided with this microactuator |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN100405122C (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102822720A (en) * | 2010-03-30 | 2012-12-12 | 奥林巴斯株式会社 | Variable spectral element |
| CN105846711A (en) * | 2016-03-30 | 2016-08-10 | 南方科技大学 | Electrostatic vibration energy collector and preparation method thereof |
| CN113568162A (en) * | 2021-07-20 | 2021-10-29 | 绍兴中芯集成电路制造股份有限公司 | Self-compensating micro-mirror driving device and compensation method of working voltage thereof |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE102014016189A1 (en) * | 2014-11-03 | 2016-05-04 | Audi Ag | Determining a position of a movable element of a linear actuator intended for a motor vehicle |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2899133B2 (en) * | 1991-06-05 | 1999-06-02 | 松下電工株式会社 | Electrostatic actuator |
| JPH09159939A (en) * | 1995-12-13 | 1997-06-20 | Nippon Telegr & Teleph Corp <Ntt> | Return light control unit |
| JP3050164B2 (en) * | 1997-05-23 | 2000-06-12 | 日本電気株式会社 | Microactuator and manufacturing method thereof |
| US6229640B1 (en) * | 1999-08-11 | 2001-05-08 | Adc Telecommunications, Inc. | Microelectromechanical optical switch and method of manufacture thereof |
| JP4441134B2 (en) * | 2001-02-08 | 2010-03-31 | オリンパス株式会社 | Electrostatic actuator and mirror array |
-
2003
- 2003-11-05 CN CNB2003801023104A patent/CN100405122C/en not_active Expired - Lifetime
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102822720A (en) * | 2010-03-30 | 2012-12-12 | 奥林巴斯株式会社 | Variable spectral element |
| CN102822720B (en) * | 2010-03-30 | 2014-11-26 | 奥林巴斯株式会社 | Variable spectral element |
| CN105846711A (en) * | 2016-03-30 | 2016-08-10 | 南方科技大学 | Electrostatic vibration energy collector and preparation method thereof |
| CN105846711B (en) * | 2016-03-30 | 2019-06-07 | 南方科技大学 | Electrostatic vibration energy collector and preparation method thereof |
| CN113568162A (en) * | 2021-07-20 | 2021-10-29 | 绍兴中芯集成电路制造股份有限公司 | Self-compensating micro-mirror driving device and compensation method of working voltage thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| CN100405122C (en) | 2008-07-23 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN1258759C (en) | Optical disk | |
| CN1090336C (en) | Diffractive optical modulator and method for producing the same, infrared sensor including such a diffractive optical mouldator and method for producing the same, and display device including such.... | |
| CN1266665C (en) | Liquid crystal display devices | |
| CN100351052C (en) | Leg-type moving robot and floor reaction force detection device therefor | |
| CN1910110A (en) | Micro actuator and device having micro actuator | |
| CN1267738C (en) | Semiconductor measurer and semiconductor measuring method | |
| CN1677846A (en) | Differential amplifier, digital-to-analog converter and display apparatus | |
| CN1259659C (en) | Optical system for recording regenerating, objective lens and optical pick device | |
| CN1437083A (en) | Reference voltage generating circuit and method, display drive circuit and display apparatus | |
| CN1306220A (en) | OPtical device, regulation method for same, and storing medium stored program | |
| CN1489716A (en) | Variable mirror and information apparatus comprising variable mirror | |
| CN1437086A (en) | Reference voltage generating circuit and method, display drive circuit and display device | |
| CN1782662A (en) | Spectrometric measuring instrument | |
| CN1334555A (en) | Liquid crystal display drive circuit, liquid crystal display and electronic device thereof | |
| CN1838277A (en) | Optical pickup apparatus | |
| CN1521714A (en) | Driving circuit for display device | |
| CN1630573A (en) | Leg-type moving robot and floor reaction force detection device thereof | |
| CN1384382A (en) | Objective, light converging optical system, optical pick-up and record and regeneration device | |
| CN1484214A (en) | LCD device | |
| CN1855259A (en) | Optical pickup and optical disk drive using same | |
| CN1522438A (en) | Optical disk device | |
| CN1866117A (en) | Liquid crystal display apparatus and method | |
| CN1519827A (en) | Optical pick-up and semiconductor laser device | |
| CN1708449A (en) | Microactuator provided with displacement detection function, and deformable mirror provided with this microactuator | |
| CN1574644A (en) | Digital/analog conversion device and display device having the same |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CX01 | Expiry of patent term |
Granted publication date: 20080723 |
|
| CX01 | Expiry of patent term |