CN101444416B - An optical fiber scanning probe and its driving method - Google Patents

Abstract

Translated fromChinese

本发明涉及一种光纤扫描探头及其驱动方法，在一片无逆压电效应的薄导电基片上对称平行粘接有两片镀有电极层的压电陶瓷片，一段末端去掉涂覆层且端面具有合适结构的裸光纤粘接在两片压电陶瓷片中间，并预留合适长度裸光纤作为振动自由端，两片压电陶瓷的电极分别接入驱动信号，驱动信号由锯齿波和正弦波叠加而成，锯齿波使两片压电陶瓷片在同一时刻产生相同的伸长或缩短量，带动光纤端头产生位置的移动完成场扫描动作，正弦波使两对压电陶瓷片产生微小长度差从而产生平行于薄导电基片的微小摆动而使光纤产生振幅较大的共振行为完成行扫描动作。本发明结构简单，有效地减小探头体积。让探头扫描更加稳定，消除成像质量不均匀的情况。

The invention relates to an optical fiber scanning probe and its driving method. Two piezoelectric ceramic sheets coated with an electrode layer are bonded symmetrically and parallelly on a thin conductive substrate without inverse piezoelectric effect. A bare optical fiber with a suitable structure is bonded between two piezoelectric ceramic sheets, and a suitable length of bare optical fiber is reserved as a free end for vibration. The electrodes of the two piezoelectric ceramics are respectively connected to the driving signal, and the driving signal consists of a sawtooth wave and a sine wave. It is superimposed, the sawtooth wave makes the two piezoelectric ceramic sheets produce the same elongation or shortening at the same time, drives the movement of the optical fiber end to complete the field scanning action, and the sine wave makes the two pairs of piezoelectric ceramic sheets produce a small length The difference produces a small swing parallel to the thin conductive substrate, so that the optical fiber produces a resonance behavior with a large amplitude to complete the row scanning action. The invention has a simple structure and effectively reduces the volume of the probe. Make probe scanning more stable and eliminate uneven imaging quality.

Description

A kind of fiber-optic scanning head and driving method thereof

Technical field

The invention belongs to the optical scanning technical field of imaging, particularly a kind of fiber-optic scanning head and driving method thereof.

Background technology

Optical imagery not only can be realized not damaged, non-intruding, Non-ionizing radiation and real-time detection and the imaging to biological tissue, and can be used for the diagnosis and the treatment of vivo biological tissue structural analysis, characterisitic parameter measurement and disease, and growth momentum is swift and violent.In order to observe mechanics of biological tissue better, the optical scanning technology is arisen at the historic moment.More representative optical scanning imaging technique has Optical Coherence Tomography Imaging Technology (Optical Coherence Tomography), the burnt micro-imaging of copolymerization, two-photon fluorescence excitation imaging.Optical Coherence Tomography Imaging Technology has good characteristics such as imaging is quick, high-resolution, and is all significant to biological tissue's research and clinical practice.The microstructure imaging that burnt micro-imaging of copolymerization and two-photon fluorescence excitation imaging can be used to organize.In order to adapt to the demand in research and the clinical practice, as scanning imagery in vivo and organize the microstructure imaging, it is imperative to make microminiaturized inner peeping type scanheads.

The inner peeping type scanheads generally adopts fiber optic conduction, and reason is that optical fiber has characteristics such as volume is little, easy to operate.At present, Chang Yong inner peeping type scanheads most variations is based on micromachine, MEMS technology, electromagnetism and electrostatic effect design.Complex structure, volume are big, higher, the not high shortcoming of image taking speed of cost but these designs exist.So researcher begins to be concerned about piezoelectric ceramics (PZT), it has advantages such as volume is little, cheap, vibration is stable.

MIT OCT group had adopted piezoelectric ceramic tube to drive the fiber-optic vibration method in 1997, successfully developed inner peeping type scanheads (Boppart SA, Bouma BE, Pitris C et al.Forward-imaging instruments for optical coherence tomography.OptLett 22:1618-1620,1997.).This is designed to the first scheme that PZT is applied to scanheads.But this scheme can only realize one-dimensional scanning, and sweep limits is less.But also brought a new thinking to researcher design inner peeping type fiber-optic scanning head.

That more representative is Li Xinde has realized a kind of two-dimentional inner peeping type fiber-optic scanning head with the piezoelectric ceramic tube of cutting apart electrode in 2004 scheme (Xiumei Liu, Michael J.Cobb, and Yuchuan Chen, Michael B.Kimmey, Xingde Li.Rapid-scanningforward-imaging miniature endoscope for real-time optical coherencetomography.Opt Lett, 29:1763-1765,2004.), and applied for United States Patent (USP) (Pub.No.:US2004/0254474).This probe has that sweep limits is big, volume is little, the image taking speed advantages of higher, but because scan mode is the two-dimensional helical shape, and imaging effect is inhomogeneous, inner outside clear.

The Ding Zhihua of Zhejiang University's contemporary optics instrument state key experiment etc. utilizes the resonance characteristics of optical fiber cantilever, structural asymmetry in conjunction with the optical fiber cantilever, it is (just yellow to have developed the two-dimensional scan fibre-optical probe that is applied to optical coherence tomography (OCT) imaging, Ding Zhihua, Wu Ling. single two-dimensional scan fibre-optical probe development .CHINESE JOURNAL OF LASERS that drives, VOL.34, No.3,2007).This design has only used a PZT just to realize the function of two-dimensional scan, has simplified the structure of probe.But the track while scan of probe is a Lissajou's figure, and the signal to noise ratio of imaging is not that very high quality to imaging can produce bigger influence.

Summary of the invention

Purpose of the present invention is at the deficiencies in the prior art and defective, plurality of advantages based on PZT, and provide a kind of fiber-optic scanning head and driving method thereof, the present invention utilizes a PZT to realize the function of two-dimensional scan, the volume of fiber-optic scanning head is littler like this, more simple while of structure sweep limits is big, the image quality height.These unique advantages be allowed to condition at clinical and scientific research on have a good application prospect.

A kind of fiber-optic scanning head, it is characterized in that, the inboard symmetrical parallel of thin conductive substrate that a slice does not have inverse piezoelectric effect is bonded with two piezoelectric ceramic pieces that are coated with electrode layer, one section end removes the bare fibre that coat and end face have suitable construction and is bonded in the middle of two piezoelectric ceramic pieces, and reserve 0.5-1.5cm length bare fibre as the vibration free end, this fiber-optic scanning head can be finished the two-dimensional scan campaign.

Described thin conductive substrate can be sheet metal or conductive carbon fibre, and its thickness is no more than 0.2mm.

Described two piezoelectric ceramic pieces that are coated with electrode layer, when after applying voltage on the electrode layer, because the effect of inverse piezoelectric effect, the deformation that piezoelectric ceramic piece will produce length direction elongates or shortens.

Described optical fiber can be single-mode fiber, multimode fibre or photonic crystal fiber.

Described end face has the bare fibre of suitable construction, and its end face can be planar end surface, hemispherical end face, parabola shaped end face or tapered end face according to the difference of application form.

A kind of driving method of fiber-optic scanning head, thin conductive substrate on the fiber-optic scanning head is connect power ground, the electrode of two piezoelectric ceramics of parallel placement inserts the driving signal respectively, driving signal is formed by stacking by two parts of signals, a part is that amplitude is bigger, the sawtooth waveforms that frequency is lower, another part is that amplitude is less, frequency just equals the double polarity sine ripple of free end mechanical fiber optic resonant frequency, the instantaneous value that drives signal for this reason the two parts of signals instantaneous value and value, the driving signal sawtooth waveforms of two piezoelectric ceramic pieces partly has identical amplitude and phase place, two piezoelectric ceramic pieces produce the identical amount of elongating or shortening at synchronization, thereby drive optic fibre end and produce moving of position, constitute the field scanning action of optical fiber scanning head.But the sinusoidal wave part of the driving signal of two piezoelectric ceramic pieces has identical amplitude position phase difference of pi just mutually, the result of its effect makes that thereby producing the tiny length difference at two pairs of piezoelectric ceramic pieces produces the small sway that is parallel to thin conductive substrate, because hunting frequency just equals to vibrate free end mechanical fiber optic resonant frequency, thereby optical fiber will produce the bigger resonance behavior of amplitude, thereby constitute the line scanning action of optical fiber scanning head.

The present invention has following characteristics:

1, the present invention utilizes two piezoelectric ceramic pieces and the thin conductive substrate of a slice to drive optical fiber formation optical-fiber two-dimensional scanheads, simplified the structure of fiber-optic scanning head, can greatly dwindle the size of fiber-optic scanning head, therefore can be deep into and spy upon the head use in the live body body in the conduct.

2, driving method has utilized the resonance characteristic of optical fiber to form line scanning cleverly, has increased the line scanning scope of optical fiber, and non-resonant scheme has been adopted in field scanning simultaneously, so there is not blind spot in scanning process.

3, because the track while scan of track while scan and other optical imaging systems is basic identical, help being used with other imaging devices.

4, detection fiber there is not specific (special) requirements, convenient with other fiber optic detection system couplings.

5, manufacture method is simple, and is with low cost, is beneficial to popularization.

Description of drawings

Fig. 1 fiber-optic scanning head structural representation.

Fig. 2 adds Y direction electric field probe deformation sketch map.

Fig. 3 deformational displacement amount is calculated sketch map.

Fig. 4 added polarity opposite electric field probe deformation sketch map.

Fig. 5 line scanning trajectory diagram of popping one's head in.

Fig. 6 drives the signal form sketch map.

Fig. 7 fibre-optical probe two-dimensional scan track sketch map.

Fig. 8 drives and probe overall structure sketch map.

Fig. 9 utilizes in the fiber-optic scanning head formation and peeps the fluorescence imaging system schematic.

The specific embodiment

The invention will be further described below in conjunction with example and accompanying drawing, but should not limit protection scope of the present invention with this.

The present invention can realize by following mode: as shown in Figure 1.

1, get the piezoelectricceramic piece 2 that two single faces are coated withelectrode layer 1, utilize epoxy resin that two piezoelectric ceramic pieces are not had on the parallel thinconductive substrate 3 that is bonded in no inverse piezoelectric effect of plated film face, the piezoelectric ceramic piece spacing is as the criterion with stand-byoptical fiber 4 diameters;

2, one section end removes thebare fibre 4 that coat and end face have suitable construction and is bonded in the middle of two piezoelectricceramic pieces 2, and reserves 0.5-1.5cm lengthbare fibre 4 as the vibration free ends;

3, the difference welding lead is fixed fiber-optic scanning head one end as signal lead on piezoelectricceramics electrode surface 1 and thinconductive substrate 3, and the other end can be finished scan function under the effect of driving signal;

4, driving signal is formed by stacking by two parts of signals, a part is the sawtooth waveforms that amplitude is big, frequency is lower, another part is that amplitude is less, and frequency just equals the double polarity sine ripple of free end mechanical fiber optic resonant frequency, the instantaneous value that drives signal for this reason the two parts of signals instantaneous value and value.The driving signal sawtooth waveforms of two piezoelectricceramic pieces 2 partly has identical amplitude and phase place, two piezoelectricceramic pieces 2 produce the identical amount of elongating or shortening at synchronization, thereby driveoptical fiber 4 terminations and produce moving of position, constitute the field scanning action of optical fiber scanning head.But the sinusoidal wave part of the driving signal of two piezoelectricceramic pieces 2 has identical amplitude position phase difference of pi just mutually, the result of its effect makes that thereby producing the tiny length difference at two piezoelectricceramic pieces 2 produces the small sway that is parallel to thinconductive substrate 3, because hunting frequency just equals to vibrate free endoptical fiber 4 mechanical resonance frequencies, therebyoptical fiber 4 will produce the bigger resonance behavior of amplitude, thereby constitute the line scanning action of optical fiber scanning head.

For operation principle of the present invention is described, definition piezoelectricceramic piece 2 length directions are the Z direction, thickness direction is the Y direction, width is a directions X, and suppose the elongation action thatpiezoelectric ceramics 2 produces length direction (Z direction) when the external electric field direction is Y direction negative direction (both:electrode layer 1 connects the driving power positive pole, and thinconductive substrate 3 connects the driving power negative pole).

Shown in Fig. 2 a, when extra electric field direction Y direction, pass through inverse piezoelectric effect, the elongation that piezoelectricceramic piece 2 produces Z direction (length direction), because there is not inverse piezoelectric effect in thinconductive substrate 3, length does not change under electric field, and therefore the result of whole effect makes the whole convex bending deformation that produces on the Y direction (thickness direction).Produce bow deformation when in like manner, direction of an electric field is opposite shown in Fig. 2 b.When with the one end fixedly the time, the other end will produce displacement owing to deformation.

With convex bending deformation is example, its displacement can roughly be estimated as follows: owing to compare with piezoelectricceramic piece 2 length l piezoelectricceramic pieces 2 absolute variable Δ l less, therefore can be with the approximate straight line of regarding as of convex bending deformation, as shown in Figure 3, length l is respectively the right-angle side and the hypotenuse of right angled triangle with distortion back length l+Δ l before the distortion, then another right-angle side length displacement that is the termination.

$\mathrm{\&Delta;y}=\sqrt{{(l+\mathrm{\&Delta;l})}^2-{\mathrm{<figure-callout\; label="l"\; filenames="H2008102374155E00011.png,H2008102374155E00012.png"\; state="\{\{state\}\}">l</figure-callout>}}^2}$

Wherein$\mathrm{\&Delta;l}=d_{31}\frac{V}{t}l,$d₃₁Be piezoelectric modulus, t is a piezoelectric ceramic piece thickness, and V is an applied voltage.

With the PZT5 canonical parameter is example, supposes l=50mm, d₃₁=360, t=0.3mm, V=200V, then

$\mathrm{\&Delta;l}=d_{31}\frac{V}{t}l=12\mathrm{\&mu;m}$

$\mathrm{\&Delta;y}=\sqrt{{(l+\mathrm{\&Delta;l})}^2-{\mathrm{<figure-callout\; label="l"\; filenames="H2008102374155E00011.png,H2008102374155E00012.png"\; state="\{\{state\}\}">l</figure-callout>}}^2}=1.1\mathrm{mm}$

The i.e. displacement of this fiber-optic scanning head under the effect of 200V voltage is 1.1mm.

Insert identical driving voltage on two piezoelectricceramic pieces 2, then two piezoelectricceramic piece 2 coefficient results are identical with a slice piezoelectric ceramics exercising result of above analysis.

If driving signal is an alternating signal, then the fiber-optic scanning head shift position will change with drive signal change.For guaranteeing the sweep limits of scanheads, usually the length ofpiezoelectric ceramics 2 is tens mm, therefore the resonant vibration frequency of itself is generally tens to hundreds of Hz, when driving signal frequency is higher than resonant frequency, the amplitude of itself will dwindle significantly, so the displacement of y direction is suitable as the lower field scanning of relative frequency.

If on two piezoelectric ceramics, add opposite polarity two electric fields, as adding on the plate electrode 1-Y direction electric field, add on anotherplate electrode 1+Y direction electric field, then a sector-meeting is along the elongation of Z direction in twopiezoelectric ceramics 2, and another sheet shortens along the Z direction.Then coefficient result makes integral body produce crooked deformation at directions X (width).Shown in Fig. 4 a, Fig. 4 b.

Has identical amplitude but the position sine wave of phase difference of pi just mutually if be added in the driving signal of two piezoelectricceramic pieces 2 and be, then Zuo Yong result makes that to produce time dependent tiny length at two piezoelectricceramic pieces 2 poor, thereby produce the small sway that is parallel to thinconductive substrate 3, if hunting frequency just equals to vibrate free endoptical fiber 4 mechanical resonance frequencies,optical fiber 4 will produce the bigger resonance behavior of amplitude, thereby constitute the line scanning action of optical fiber scanning head.According to Theory of Vibration, the natural frequency f that can vibrate free end optical fiber is:

$f=\frac{\mathrm{\&beta;}}{4\mathrm{\&pi;}}\sqrt{\frac{E}{\mathrm{\&rho;}}}\left(\frac{R}{L^2}\right)$

In the formula, L is the free end fiber lengths, and R is a fiber radius, and E is the optical fiber Young's modulus, and ρ is a density of optic fibre, and β is a constant by vibration modulus and boundary condition decision.After optical fiber was selected, because R, E and ρ also are constant, the natural frequency of optical fiber was only relevant with length, can reach specific rate of scanning by regulating vibration free endoptical fiber 4 length.When the frequency that drives signal during near the optical fiber natural frequency,optical fiber 4 is in resonance state, and it is maximum that the amplitude of vibration will reach.This shows, whether the optical fiber amplitude of line scanning depends primarily on frequency accurate, therefore and little with the amplitude relation of piezoelectricceramic piece 2, in frequency accurately under the prerequisite, the driving voltage that 2 needs of piezoelectric ceramic piece are very little just can make the bigger sweep limits ofoptical fiber 4 generations.

Be example with above PZT5 material still, when drive signal amplitude was the 10V peak-to-peak value, sweep limits can reach more than 500 microns.Actual scanogram as shown in Figure 5.

In sum, finish the two-dimensional scan action for making fiber-optic scanning head, driving signal demand is made of two parts, a part is the sawtooth waveforms that amplitude is big, frequency is lower, as field scanning, another part is that amplitude is less, and frequency just equals the double polarity sine ripple of free end mechanical fiber optic resonant frequency, as line scanning, the instantaneous value that drives signal for this reason the two parts of signals instantaneous value and value.

The driving signal sawtooth waveforms of two piezoelectricceramic pieces 2 partly has identical amplitude and phase place, two piezoelectricceramic pieces 2 produce the identical amount of elongating or shortening at synchronization, thereby driveoptical fiber 4 terminations and produce moving of position, constitute the field scanning action of optical fiber scanning head.But the sinusoidal wave part of the driving signal of two piezoelectricceramic pieces 2 has identical amplitude position phase difference of pi just mutually, the result of its effect makes that thereby producing the tiny length difference at two pairs of piezoelectricceramic pieces 2 produces the small sway that is parallel to thin conductive substrate, because hunting frequency just equals to vibrate free endoptical fiber 4 mechanical resonance frequencies, therebyoptical fiber 4 will produce the bigger resonance behavior of amplitude, thereby constitute the line scanning action of optical fiber scanning head.Optical fiber 4 movement locus after two actions are synthetic as shown in Figure 7.

Embodiment one: the making of fiber-optic scanning head.Step is as follows

1, gets 2 two of the piezoelectric ceramic pieces that length that single face is coated withelectrode layer 1 is 50mm, width 0.2mm, thickness 0.2mm, getting 53 millimeters of thickness length, width 0.6mm, thickness is scale copper 3 a slices of 0.1mm, utilize epoxy resin with two piezoelectric ceramic pieces, 2 parallel being bonded on thecopper sheet 3, piezoelectricceramic piece 2 one ends are concordant withcopper sheet 3 terminations, and two piezoelectricceramic piece 2 spacings are 0.2mm.

2, a section single-mould fiber end is removed 30～40mm coat and exposebare fibre 4, it is smooth to utilize the fiber cut cutter that fiber end face is cut,optical fiber 4 is placed gap between two piezoelectric ceramic pieces, and reserve 10mm length (resonant frequency is about 1KHz) as the vibration free end, utilize epoxy resin withoptical fiber 4 strong bond in 2 gaps of two piezoelectric ceramic pieces.

3, the difference welding lead is fixed non-fiber one end as signal lead on 1 of piezoelectric ceramics electrode layer andcopper sheet 3.

4, signal lead on thecopper sheet 3 is connect signal ground, two piezoelectric ceramic piece lead-in wires insert thedriving power 5 driving signal of form as shown in Figure 6 respectively, driving signal is formed by stacking by two parts of signals, a part for amplitude be 0～200V, frequency be 4Hz, rise time and fall time ratio be 9: 1 sawtooth waveforms, another part is peak-to-peak value 10V, the double polarity sine ripple of frequency 1KHz, the instantaneous value that drives signal for this reason the two parts of signals instantaneous value and value.

5, the driving signal sawtooth waveforms of two piezoelectricceramic pieces 2 partly has identical amplitude and phase place, two piezoelectricceramic pieces 2 produce the identical amount of elongating or shortening at synchronization, thereby driveoptical fiber 4 terminations and produce moving of 4Hz, the about 1.1mm of scope, constitute the field scanning action of optical fiber scanning head.But the sinusoidal wave part of the driving signal of two piezoelectricceramic pieces 2 has identical amplitude position phase difference of pi just mutually, thereby the result of its effect makes that producing the tiny length differences at two pairs of piezoelectricceramic pieces 2 produces the small sway that is parallel to thin conductive substrate.Because hunting frequency (1KHz) just equals to vibrate free endoptical fiber 4 mechanical resonance frequencies (1KHz),optical fiber 4 will produce amplitude and be about 500 microns vibration, thereby constitute the line scanning action of optical fiber scanning head.

Embodiment two: utilize in the fiber-optic scanning head formation and peep the fluorescence imaging system.In peep the fluorescence imaging system schematic as shown in Figure 9.

1, make fiber-optic scanning head as embodiment one step after, it is inserted in a diameter is in the 2mm stainless steel tube 6, stainless steel tube 6 one ends are installed dimpling lens 7 in advance and are used for the focusing of optical fiber emergent light and the collection of fluorescence.

2, adjust the position of fiber-optic scanning head in stainless steel tube 6, make optical fiber axle center and lens 7 optical axis coincidences, and adjustmentoptical fiber 4 bonds together with the lead end and the stainless steel tube 6 of epoxy resin 8 with fibre-optical probe to suitable distance with lens 7.

3, the signal lead of optical fiber and probe is inserted in rubber sheath 9 backs and draws, utilize epoxy resin 8 that rubber sheath 9 and stainless steel tube 6 are bonded together, and guarantee good seal from the other end of stainless steel tube 6.

4, the light that sends of excitation source 10 is reflected by dichroic mirror 11 after overcoupling lens 12 are coupled in theoptical fiber 4, exciting light focuses on the fluorescence staining sample 13 to be measured through lenticule 7 after the fiber-optic scanning head outgoing and excited sample 13 is sent fluorescence, fluorescence is collected and is coupled in theoptical fiber 4 of fiber-optic scanning head by lenticule 7, passes dichroic mirror 11 throughoptical fiber 4 transmission back scioptics 12 collimations and is radiated on the photomultiplier tube 14.

5, drivingpower 5 drives fiber-optic scanning head and realizes two-dimensional scan, and drivingpower 5 will drive signal and send into image processing system 15 simultaneously.

6, image processing system 15 fluorescence intensity that photomultiplier tube 14 is noted is corresponding one by one with the sweep signal of drivingpower 5, promptly constitutes complete scanogram.

7, will encapsulate the back fiber-optic scanning head is inserted into and peeps fluorescence imaging in can carrying out in the organism.

Claims (5)

Translated fromChinese

1.一种光纤扫描探头，其特征在于：在一片无逆压电效应的薄导电基片上对称平行粘接有两片镀有电极层的压电陶瓷片，一段末端去掉涂覆层且端面具有合适结构的裸光纤粘接在两片压电陶瓷片中间，并预留0.5-1.5cm长度裸光纤作为振动自由端，所述的两片镀有电极层的压电陶瓷片，当在电极层上施加电压后，压电陶瓷片将产生长度方向的形变：伸长或缩短。1. An optical fiber scanning probe is characterized in that: on a thin conductive substrate without inverse piezoelectric effect, two piezoelectric ceramic sheets plated with an electrode layer are bonded symmetrically in parallel, and one section of the end removes the coating layer and the end face has A bare optical fiber with a suitable structure is bonded between two piezoelectric ceramic sheets, and a bare optical fiber with a length of 0.5-1.5 cm is reserved as a free end for vibration. The two piezoelectric ceramic sheets coated with an electrode layer, when the electrode layer After a voltage is applied to the piezoelectric ceramic sheet, it will deform in the longitudinal direction: elongation or shortening.2.根据权利要求1所述的光纤扫描探头，其特征在于：所述的薄导电基片为金属片或导电碳纤维，其厚度不超过0.2mm。2. The optical fiber scanning probe according to claim 1, wherein the thin conductive substrate is a metal sheet or conductive carbon fiber, and its thickness is not more than 0.2mm.3.根据权利要求1所述的光纤扫描探头，其特征在于：所述的光纤为单模光纤、多模光纤或光子晶体光纤。3. The optical fiber scanning probe according to claim 1, wherein the optical fiber is a single-mode optical fiber, a multi-mode optical fiber or a photonic crystal optical fiber.4.根据权利要求1所述的光纤扫描探头，其特征在于：所述的端面具有合适结构的裸光纤，裸光纤端面为平端面、半球形端面、抛物线形端面或锥形端面。4. The optical fiber scanning probe according to claim 1, characterized in that: the end face has a bare optical fiber with a suitable structure, and the end face of the bare optical fiber is a flat end face, a hemispherical end face, a parabolic end face or a tapered end face.5.一种光纤扫描探头的驱动方法，其特征在于：将根据权利要求1-4之一所述的光纤扫描探头上薄导电基片接电源地线，平行放置的两片压电陶瓷的电极分别接入驱动信号，驱动信号由锯齿波和双极性正弦波两部分信号叠加而成，驱动信号的瞬时值为此两部分信号瞬时值的和值；两片压电陶瓷片的驱动信号锯齿波部分具有相同的幅值和相位，两片压电陶瓷片在同一时刻产生相同的伸长或缩短量，从而带动光纤端头产生位置的移动，构成光纤扫描头的场扫描动作；两片压电陶瓷片的驱动信号正弦波部分具有相同的幅值但是位相刚好相差π，使得在两对压电陶瓷片产生微小长度差从而产生平行于薄导电基片的微小摆动，由于摆动频率刚好等于振动自由端光纤机械共振频率，光纤将产生振幅较大的共振行为，从而构成光纤扫描头的行扫描动作。5. A driving method for an optical fiber scanning probe, characterized in that: the thin conductive substrate on the optical fiber scanning probe according to one of claims 1-4 is connected to the power supply ground wire, and the electrodes of two piezoelectric ceramics placed in parallel The driving signal is respectively connected, and the driving signal is composed of a sawtooth wave and a bipolar sine wave. The instantaneous value of the driving signal is the sum of the instantaneous value of the two parts of the signal; The wave part has the same amplitude and phase, and the two piezoelectric ceramic sheets produce the same amount of elongation or shortening at the same time, thereby driving the movement of the optical fiber end to form the field scanning action of the optical fiber scanning head; The sine wave part of the driving signal of the electric ceramic sheet has the same amplitude but the phase difference is just π, so that there is a small length difference between the two pairs of piezoelectric ceramic sheets to produce a small swing parallel to the thin conductive substrate, because the swing frequency is just equal to the vibration The mechanical resonance frequency of the free-end optical fiber, the optical fiber will produce a resonance behavior with a large amplitude, thus constituting the line scanning action of the optical fiber scanning head.

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