CN113607062A - Micro-actuator displacement and inclination angle measuring device and method - Google Patents

Micro-actuator displacement and inclination angle measuring device and method Download PDF

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CN113607062A
CN113607062A CN202110882268.2A CN202110882268A CN113607062A CN 113607062 A CN113607062 A CN 113607062A CN 202110882268 A CN202110882268 A CN 202110882268A CN 113607062 A CN113607062 A CN 113607062A
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actuator
laser
plane
displacement
mirror
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CN113607062B (en
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刘维新
唐宁
夏利东
左修辉
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Shandong University
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B11/00—Measuring arrangements characterised by the use of optical techniques
    • G01B11/02—Measuring arrangements characterised by the use of optical techniques for measuring length, width or thickness
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B11/00—Measuring arrangements characterised by the use of optical techniques
    • G01B11/26—Measuring arrangements characterised by the use of optical techniques for measuring angles or tapers; for testing the alignment of axes

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Abstract

The invention provides a micro-actuator displacement and inclination angle measuring device and method. The laser resonant cavity is composed of a fixed cavity mirror and an independent cavity mirror, an antireflection film-coated glass sheet is obliquely arranged between the independent cavity mirror and the laser gain tube along the laser axis, two weak light beams reflected by the surface of the glass sheet are incident to a plane reflector driven by an actuator, and the two weak light beams are coupled back to resonate to form bifurcated cavity laser feedback after being folded back. In the motion process of the actuator, a light intensity change stripe formed by laser feedback is received and recorded through a photoelectric detector, and the displacement and the inclination angle of the actuator are calculated according to the period and the envelope characteristic of the feedback stripe. The invention can simultaneously measure the displacement and the inclination angle of the micro-displacement actuator in the linear expansion and contraction process and evaluate the performance index of the micro-displacement actuator.

Description

Micro-actuator displacement and inclination angle measuring device and method
Technical Field
The invention relates to the technical field of optical measurement, in particular to a micro-actuator displacement and inclination angle measuring device.
Background
The precisely controllable linear displacement has important application in various fields such as manufacturing, materials, scientific research and the like. With the increasing requirement for displacement accuracy, micro-displacement actuators driven by stepping motors or servo motors, piezoelectric ceramics, voice coil motors, etc. are developed gradually, and the performance index of the micro-displacement actuators determines the processing or measuring accuracy.
The actuator, driven by the power supply, may present a yaw angle with respect to the axis in addition to a linear elongation along the axis, mainly due to material and structural non-uniformities, already caused by the driving voltage differences. Therefore, in the working process of the actuator, on one hand, the resolution of the displacement variation along with the drive source (such as a voltage signal) is high, the linearity is good, and the displacement hysteresis is reduced as much as possible; on the other hand, the direction is good in the displacement process, and the inclination angle relative to the axis is reduced as much as possible.
In order to test the displacement performance and the inclination angle of different types of actuators, an interferometer which has higher precision and can trace to the laser wavelength is generally adopted. However, in the optical path of the interferometer, the components for measuring displacement and measuring inclination angle are independent, i.e. only one of the two components can be measured, and in practical application, if the piezoceramic actuator needs to simultaneously measure the inclination angle in the process of extension, the measurement cannot be performed through the interferometer. In addition, the displacement and inclination angle measurement components of the laser interferometer are large in size and weight, and the stress state of the components can be obviously changed in the driving process of the micro-displacement actuator, so that system errors are brought to measurement.
Disclosure of Invention
The present invention is directed to solving one of the above problems and providing a device capable of simultaneously measuring a micro tilt angle and a displacement change of a micro-actuator.
In order to achieve the purpose, the invention adopts the technical scheme that:
micro-actuator displacement and tilt measurement apparatus comprising:
laser gain tube: one end of the fixed cavity mirror is connected with the high-reflection film plated fixed cavity mirror, and the other end of the fixed cavity mirror is connected with the anti-reflection film plated glass window sheet;
independent chamber mirror: the laser gain tube mirror is arranged at an interval, one surface plated with the high reflection film faces one side of the glass window sheet and is arranged in parallel with the fixed cavity mirror to form a laser resonant cavity, and the laser resonant cavity and the fixed cavity are arranged at an interval, namely the length of the resonant cavity;
optical glass sheet: the gain tube is arranged between the gain tube glass window and the independent cavity mirror, is inclined at a certain angle with the laser beam in the resonant cavity, and comprises a first plane close to one side of the gain tube and a second plane close to one side of the independent cavity mirror, and the two planes are plated with antireflection films;
the actuator is arranged on a reflected light path of the laser passing through the optical glass sheet and is adjusted to generate micro-displacement along the direction of the laser beam;
a plane mirror: the two light primary paths reflected by the first plane and the second plane of the reflecting optical glass sheet return to the laser resonant cavity; a branched cavity attached to the laser resonant cavity is formed between the optical glass sheet and the plane reflector;
a photoelectric detector: the tail light detector is arranged on one side of the fixed cavity mirror, which is far away from the independent cavity mirror, and is used for detecting tail light output from the fixed cavity mirror and converting the tail light into an electric signal which changes along with time;
a data processing unit: the laser feedback stripe is measured according to the detected light intensity change curve when the laser branched cavity is fed back, and the displacement and the inclination angle of the actuator are calculated;
the displacement is the displacement of the actuator approaching or departing from the optical glass sheet along the direction of the laser axis in the branched cavity under the driving of the power supply, and the inclination angle is the angle change relative to the propagation direction of the laser axis.
In some embodiments of the invention, the data processing unit is configured to calculate the actuator displacement Δ L as follows:
ΔL＝λ/2(M+m)；
wherein, λ is the laser wavelength, M is the feedback stripe integer part, M is the feedback stripe decimal part obtained according to the light intensity variation phase, and the feedback stripe decimal part is obtained according to the light intensity variation curve detected by the photoelectric detector;
the data processing unit is configured to calculate the tilt angle of the actuator as follows
Figure BDA0003192488570000022
Figure BDA0003192488570000021
Wherein: d is a light beam ErAnd a light beam Er'The distance between the two chambers is epsilon, a bifurcated cavity length difference coefficient caused by micro-actuator displacement and inclination angle is epsilon, and N is a period number of half-wavelength fluctuation under one long-period envelope in a light intensity change curve in the actuator expansion and contraction process; 10800 is a radian to angle conversion factor;
Erfor emitting laser through the gain tube, on the first plane F of the optical glass sheet1After being reflected to the plane mirror, the light is transmitted to the plane mirror and then reflected back to the laser resonant cavity by the plane mirror; er'For emitting laser through the gain tube, on the first plane F of the optical glass sheet1Refracted to a second plane F2Through the second plane F2Reflected to a first plane F1Then passes through a first plane F1And refracting the optical glass sheet, transmitting the optical glass sheet to the plane reflector, and reflecting the light returned to the resonant cavity by the plane reflector.
In some embodiments of the present invention, there is further provided a method for measuring displacement and tilt angle of a micro-actuator, using the above-mentioned testing apparatus, including the following steps:
calculating actuator displacement Δ L: obtaining an integer part M and a decimal part M of the laser feedback stripes according to the image of the photoelectric detector;
ΔL＝λ/2(M+m)；
calculating tilt angle of actuator
Figure BDA0003192488570000032
The method comprises the following steps:
Figure BDA0003192488570000031
wherein: d is a light beam ErAnd a light beam Er'The distance between the two chambers is epsilon, a bifurcated cavity length difference coefficient caused by micro-actuator displacement and inclination angle is epsilon, and N is a period number of half-wavelength fluctuation under one long-period envelope in a light intensity change curve in the actuator expansion and contraction process; 10800 is a radian to angle conversion factor;
Erfor emitting laser light through the gain tube, at the first side of the optical glass sheetA plane F1After being reflected to the plane mirror, the light is transmitted to the plane mirror and then reflected back to the laser resonant cavity by the plane mirror; er'For emitting laser through the gain tube, on the first plane F of the optical glass sheet1Refracted to a second plane F2Through the second plane F2Reflected to a first plane F1Then passes through a first plane F1And refracting the optical glass sheet, transmitting the optical glass sheet to the plane reflector, and reflecting the light returned to the resonant cavity by the plane reflector.
In some embodiments of the invention, the method further comprises:
obtaining tilt data for a first set of actuators at a first angle calculation;
rotating the actuator by 90 degrees, and repeating the calculation step of the inclination angle of the actuator;
obtaining tilt data for a second set of actuators at a second angle calculation;
and combining the first set of tilt angle data and the second set of tilt angle data to obtain an actual tilt angle and a tilt direction during the displacement of the actuator.
Compared with the prior art, the invention has the advantages and positive effects that:
(1) the invention can simultaneously measure the displacement and the inclination angle of the micro-displacement actuator in the linear extension process and evaluate the performance index of actuation.
(2) The invention can calculate the displacement and the inclination angle of the actuator by calculating the number of the feedback stripes in the measuring process, and has high linearity; the magnitudes of actuator displacement and tilt can be correlated to the laser wavelength, enabling the measurement to be traced to the reference for length, the laser wavelength.
Drawings
FIG. 1 is a schematic diagram of an actuator displacement and tilt angle measuring device according to the present invention;
FIG. 2 is a schematic diagram of the optical path of the displacement and tilt measuring device of the actuator of the present invention;
FIG. 3 is a state diagram of the actuator without displacement;
FIG. 4 is a state diagram of displacement of the actuator with tilt;
FIG. 5 is a graph of displacement of the actuator along the laser axis with the laser intensity at the tilt position.
In the above figures:
1. the device comprises a laser gain tube, 2 parts of a fixed cavity mirror, 3 parts of an anti-reflection window sheet, 4 parts of an independent cavity mirror, 5 parts of a glass sheet, 6 parts of an actuator, 7 parts of a plane mirror, 8 parts of a photoelectric detector and 9 parts of a data processing unit.
Detailed Description
The invention is described in detail below by way of exemplary embodiments. It should be understood, however, that elements, structures and features of one embodiment may be beneficially incorporated in other embodiments without further recitation.
In the description of the present invention, it should be noted that the terms "upper", "lower", "front", "rear", and the like indicate orientations or positional relationships based on positional relationships shown in the drawings, and are only for convenience in describing the present invention and simplifying the description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention.
It will be understood that when an element is referred to as being "disposed on," "connected to," or "secured to" another element, it can be directly on the other element or be indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or be indirectly connected to the other element. Furthermore, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
The invention provides a micro-actuator displacement and inclination angle measuring device, which can be a micro-displacement actuator such as piezoelectric ceramics and a voice coil motor.
Referring to fig. 3 and 4, the direction of laser propagation from left to right is illustrated, which is defined as the initial propagation direction of laser light, and the displacement described herein refers to the displacement of the actuator 6 toward or away from the optical glass sheet along the laser axis in the bifurcated cavity under the driving of the power supply, and is represented as the upward or downward direction shown in fig. 3; the tilt angle referred to herein means the angular change of the actuator with respect to the propagation direction of the laser axis, and is represented by the swing direction shown in fig. 4. The reason why the actuator generates displacement and inclination angle is: when the actuator 6 applies voltage, each end face of the actuator generates elongation, and the elongation movement is performed towards the initial propagation direction of the laser; however, due to the non-uniformity of the material and structure of the actuator 6, the elongation motion generated by the actuator 6 is non-uniform, and thus, the tilt angle is generated.
The structure of the measuring device is shown in fig. 1, and comprises:
laser gain tube 1: one end of the fixed cavity mirror 2 is connected with the high-reflection film plated, and the other end of the fixed cavity mirror 3 is connected with the anti-reflection film plated glass window sheet; the light-emitting direction of the light-emitting device faces the independent cavity mirror 4; the diameter of the capillary tube in the gain tube 1 is small, and light deviating from the diameter range of the capillary tube cannot return through the gain tube 1;
independent chamber mirror 4: the laser gain tube mirror 1 is arranged at an interval, one surface plated with a high reflection film faces one side of the glass window sheet and is arranged in parallel with the fixed cavity mirror 2 to form a laser resonant cavity, and the interval between the laser resonant cavity and the fixed cavity mirror is L0The distance between the two is the cavity length of the resonant cavity;
optical glass sheet 5: is arranged between the gain tube glass window 3 and the independent cavity mirror 4 and is inclined at a certain angle with the laser beam in the resonant cavity, specifically, the normal direction of the gain tube glass window is at an angle theta relative to the light-emitting direction of the gain tube, the thickness of the gain tube glass window is d, and the gain tube glass window comprises a first plane F close to one side of the gain tube 11And a second plane F adjacent to one side of the independent cavity mirror2Plating antireflection films on the two planes; the laser is reflected after being irradiated to the optical glass sheet 3, and the actuator 6 is arranged on a reflection light path of the laser passing through the optical glass sheet; in some embodiments, antireflection films may be disposed on both sides of the optical glass sheet 3, and after the antireflection films are disposed, the reflection coefficient of light may be reduced, and the reflection amount of light after passing through the optical glass sheet 3 may be reduced; the optical glass sheet 5 is positioned in the resonant cavity and forms an angle theta with the laser, and the angle can be selected according to requirements and can be set to be 45 degrees for example;
the actuator 6 is arranged on a reflected light path of the laser passing through the optical glass sheet and is adjusted to generate micro-displacement along the direction of the laser beam;
plane mirror 7: arranged to be actuatedThe end face of the device facing one side of the optical glass sheet 5 is arranged in parallel to the initial propagation direction of the laser; first plane F of reflective optical glass sheet1And a second plane F2Two reflected light beams return to the laser resonant cavity in a primary path; a branched cavity attached to the laser resonant cavity is formed between the optical glass sheet 5 and the plane reflector 7, and the length of the branched cavity is lbThe length is defined as the distance between the incident point of the laser light incident on the optical glass sheet 5 from the end of the gain tube 1 and the plane mirror 7; when the actuator 6 is rotated, the length of the bifurcation cavity will change; the direction of the laser reflected to the plane reflector 7 by the optical glass sheet 3 is the laser axis transmission direction;
the photodetector 8: the tail light detector is arranged on one side of the fixed cavity mirror, which is far away from the independent cavity mirror, and is used for detecting tail light output from the fixed cavity mirror and converting the tail light into an electric signal which changes along with time;
the data processing unit 9: and the photoelectric detector 8 is connected with the laser feedback stripe and is used for measuring the laser feedback stripe according to the detected light intensity change curve when the laser branched cavity is fed back, and calculating the displacement and the inclination angle of the actuator 6.
The data processing unit calculates the displacement Δ L of the actuator 6 based on the following method:
ΔL＝λ/2(M+m)；
wherein, λ is the laser wavelength, M is the feedback stripe integer part, M is the feedback stripe decimal part obtained according to the light intensity variation phase, and the feedback stripe decimal part is obtained according to the light intensity variation curve detected by the photoelectric detector;
the data processing unit is configured to calculate the tilt angle of the actuator as follows
Figure BDA0003192488570000062
Figure BDA0003192488570000061
Wherein: d is a light beam ErAnd a light beam Er'The distance between the two is the length difference coefficient of the branched cavity caused by the displacement and the inclination angle of the micro-actuator, and is the inclination angle of the actuator
Figure BDA0003192488570000063
And the displacement delta L determines a small amount, and N is the periodicity of half-wavelength fluctuation under a long period envelope in a light intensity change curve in the expansion and contraction process of the actuator; 10800 is a transform factor for radian conversion to an angle in units;
Erfor laser passing through gain tube, on the first plane F of optical glass sheet1After being reflected to the plane mirror, the light is transmitted to the plane mirror and then reflected back to the laser resonant cavity by the plane mirror; er'For emitting laser through the gain tube, at a first plane F of the optical glass sheet 51Refracted to a second plane F2Through the second plane F2Reflected to a first plane F1Then passes through a first plane F1And refracting the optical glass sheet, transmitting the optical glass sheet to the plane reflector, and reflecting the light returned to the resonant cavity by the plane reflector.
The following describes the principles of the present invention in detail.
The resonant cavity of the standing wave laser consists of a fixed cavity mirror 2 and an independent cavity mirror 4, and the oscillating optical field meets the resonance condition. When the output laser is reflected by the optical surface outside the resonant cavity, the output laser returns to the resonant cavity and is overlapped with the oscillating optical field to form interference, namely laser feedback or self-mixing interference. When the external optical reflection surface (usually a mirror with a specific reflectivity) changes, the phase of the feedback light returning to the resonant cavity is correspondingly changed, which can cause the laser intensity to change to form a feedback stripe.
An optical glass sheet 5 is placed in the laser resonant cavity, the optical glass sheet inclines along the laser axis to enable part of light in the cavity to be reflected to the outside of the laser, a plane reflector 7 is arranged on the reflected light path to enable the light to be incident back to the resonant cavity along the original path, laser feedback is formed similarly, and the laser intensity is changed.
Because the optical glass sheet 5 in the cavity and the plane reflector 7 outside the cavity form a branched cavity structure independent of the laser resonant cavity, the reflectivity of the surface of the element is low, two beams of incident light formed by the branched cavity can not influence laser oscillation, but the output light intensity can be changed, and a laser feedback effect is generated. When the off-cavity plane mirror 7 is displaced in the laser direction, the light intensity changes periodically. According to the laser physics, the light intensity of the laser changes for one period every time the plane mirror 7 of the branched cavity moves for one half of the wavelength of the light, and a feedback stripe is formed. When the reflector is driven by the actuator with linear displacement, the number of feedback stripes is measured, and the displacement of the micro actuator can be obtained.
Specifically, the optical path propagation of the laser light after passing through the actuator displacement and tilt angle measuring device is schematically shown in fig. 2. Hereinafter, a method for measuring the tilt angle and the displacement of the micro-actuator using the device provided by the present invention will be described with reference to the accompanying drawings.
The initial light wave emitted by the fixed cavity mirror 2 is transmitted towards the right side of the figure, and the complex amplitude of the electric field vector of the initial light wave is E0The electric field vector complex amplitude is changed into E after the right propagation in the resonant cavity is a positive direction and is amplified by the laser gain tube 1 and attenuated by the anti-reflection window sheet 3i。
Because two surfaces before intracavity optical glass piece 5 back can all reflect laser, actually the branching chamber has two bundles of parallel laser:
one beam is ErEmitting laser light E for gain tube 1iFirst plane F of optical glass sheet 51After being reflected to the plane reflector 7, the light is transmitted to the plane reflector 7 and refracted back by the plane reflector 7;
one beam is Er'Emitting laser light E for gain tube 1iFirst plane F of optical glass sheet 51Refracted to a second plane F2Through the second plane F2Reflected to a first plane F1Then passes through a first plane F1The light refracted out of the optical glass sheet 5 is transmitted to the plane reflector 7, and then is refracted back by the plane reflector 7.
Reflected light ErAnd Er'Is reflected by the plane mirror 7 and returns to the first plane F1And a second plane F2After once refraction and reflection, three paths of light beams are generated respectively:
Er: is first plane F1Reflecting to form reflected light ErrThe reflected light returns along the capillary gain tube; along a first plane F1Refracting and further along a second plane F2Refracted and pass through a second plane F2The light is passed out to form refracted light Ert(ii) a Is first plane F1Refracting and further along a second plane F2Reflected by the first plane F1Refracted and pass through a first plane F1Then the light passes out to form a return light Err'；
Er': is first plane F1Reflecting to form reflected light Er'r(ii) a Along a first plane F1Refracting and further along a second plane F2Refracted and pass through a second plane F2The light is passed out to form refracted light Er't(ii) a Is first plane F1Refracting and further along a second plane F2Reflected by the first plane F1Refracted and pass through a first plane F1Then the light passes out to form a return light Er'r'The reflected light returns along the capillary gain tube.
Since the diameter of the capillary in the gain tube 1 is small, the above-mentioned Err'、Er'tAnd not back to the gain chamber. Meanwhile, the reflection coefficient of the surface of the optical glass sheet 5 is very small due to the antireflection coating, so that only two times of reflected light and less than two times of reflected light on the two surfaces of the optical glass sheet 5 are considered, the intensity of high-order reflected light is too small to be ignored, and only E is consideredrr、Er'r'And returns to the gain chamber.
The folding back of the optical path from the fixed cavity mirror 2 to the independent cavity mirror 4 is as follows.
EiTransmitted light E from optical glass sheet 5tAfter propagating to the independent cavity mirror 4, the electric field vector complex amplitude is changed into E1The original path returns to pass through the optical glass sheet 5 again, and after being reflected and transmitted by the two surfaces, the primary reflected light respectively follows the original ErtAnd Er't，Err'Cannot enter the laser gain tube 1, only the transmitted light E2Can be returned to the fixed cavity mirror 2 via the capillary.
In summary, in the optical path, the light returning to the resonant cavity includes: err、Er'r'、E2。
The principle of estimation for calculating the displacement and tilt of the micro-actuator is as follows.
It is known that: refraction of airA rate of n0Refractive index of glass n1The incident angle of the laser in the resonant cavity reaching the glass sheet 5 is thetaiAngle of reflection θrθ, the angle of refraction is:
θt＝arcsin(n0/n1·sinθ)。
e can be calculated based on the above-mentioned indexrAnd Er'Optical path difference to the plane mirror 7:
Figure BDA0003192488570000091
then Err、Er'r'The optical path difference returning to the incident point is: 2 Delta l.
Then Err、Er'r'The phase delay amount of (d) is: 2 Δ Φ ═ 4 pi Δ l/λ.
Further, the electric field vector complex amplitude of each light returning to the resonant cavity after passing through the independent cavity mirror 4, the optical glass sheet 5 and the plane reflector 7 can be calculated as follows:
Figure BDA0003192488570000092
where g is the gain coefficient of the active medium, laTo activate the effective length of the medium (He-Ne laser capillary gain tube), glaThe one-way gain is obtained by the laser passing through the gain tube once in the resonant cavity, L' is the equivalent physical cavity length of the laser resonant cavity, and k is the wave vector: k 2 pi/λ.
In the process of calculating the equivalent physical cavity length of the laser resonant cavity, the refractive indexes of the laser gain medium, the anti-reflection window sheet 3 and the optical glass sheet 5 are considered, and the following steps are obtained:
Figure BDA0003192488570000093
then according to the self consistent condition, the light field from the fixed cavity mirror 2 goes back and forth a circle in the cavity, and after returning to the fixed cavity mirror 2, the light field should be consistent with the initial state, then there are:
E0＝E2+Err+Er'r'；
namely:
Figure BDA0003192488570000094
meanwhile, for the optical glass sheet 7 with the antireflection film coated on the surface, the reflectivity is far less than 1, and the transmissivity is approximately equal to 1. By simplifying equation (3) and eliminating higher order small quantities, the laser gain can be expressed as:
Figure BDA0003192488570000095
wherein:
Figure BDA0003192488570000096
l1＝l+lb-L'，l2＝l+lb+Δl-L'。
when the length of the bifurcation cavity is lbIn the change, the laser intensity generates sinusoidal modulation with a period of λ 2, that is, when the plane mirror 7 is driven by the actuator, the laser intensity changes by one period (feedback fringe) every time λ 2 is displaced, and then the total displacement Δ L (linear elongation) of the actuator is:
ΔL＝λ/2(M+m)； (5)
wherein, M is the integral part of the feedback stripe, and M is the decimal part of the feedback stripe obtained according to the phase of the light intensity change. The light wave image obtained by reference detection can be obtained by the data processing unit 9, the whole period number is M, and the part less than one period is converted into a fractional part M according to the phase.
The actuators 6 are energized so that the extensions of the points on the end surfaces thereof are not uniform, and the plane mirror 7 has a small yaw angle with respect to the surface normal
Figure BDA0003192488570000102
After passing through the reflector 7, the two light beams are alongThe displacement amounts in the respective axial directions are not equal, and a difference exists between them. According to l in formula (4)1And l2The following steps are changed:
l1′＝l+(1-ε/2)lb-ΔL-L′,l2′＝l+(1+ε/2)lb-ΔL+Δl-L′； (6)
by substituting equation (6) for equation (4), the variation curve of the laser intensity formed during the displacement of the actuator 6 can be calculated as shown in fig. 5.
It can be seen that as the actuator 6 is displaced, the bifurcated lumen length lbInstead, a long-period envelope appears on the light intensity fluctuation curve with a period λ 2. The average displacement of the actuator 6 can be obtained in accordance with the light intensity fluctuation period, instead of equation (5). And the size of the deflection angle in the elongation process of the actuator 6 is calculated according to the half-wavelength fluctuation cycle number N under one long-period envelope in the light intensity curve:
Figure BDA0003192488570000101
thereby, the linear extension Δ L of the actuator 6 and the yaw angle in the x-axis direction can be obtained simultaneously
Figure BDA0003192488570000103
Obtaining tilt data for a first set of actuators at a first angle calculation;
rotating the actuator by 90 degrees, and repeating the calculation step of the inclination angle of the actuator;
obtaining tilt data for a second set of actuators at a second angle calculation;
and combining the first set of tilt angle data and the second set of tilt angle data to obtain an actual tilt angle and a tilt direction during the displacement of the actuator.
For example, the actuator 6 may be rotated 90 ° relative to the laser axis, and continuing the above test, the pitch angle ζ in the y-direction may be obtained. Combining two angles of inclination
Figure BDA0003192488570000111
And ζ, can be actuatedThe actual angle of inclination and the direction of inclination of the device 6 during elongation.
The above description is only a preferred embodiment of the present invention, and not intended to limit the present invention in other forms, and any person skilled in the art may apply the above modifications or changes to the equivalent embodiments with equivalent changes, without departing from the technical spirit of the present invention, and any simple modification, equivalent change and change made to the above embodiments according to the technical spirit of the present invention still belong to the protection scope of the technical spirit of the present invention.

Claims (4)

1.微致动器位移及倾角测量装置，其特征在于，包括：1. micro-actuator displacement and inclination measuring device, is characterized in that, comprises: 激光增益管：一端连接镀高反射膜的固定腔镜，一端连接镀增透膜的玻璃窗片；Laser gain tube: one end is connected to a fixed cavity mirror coated with a high reflection film, and one end is connected to a glass window coated with an antireflection coating; 独立腔镜：与激光增益管镜间隔设置，镀高反膜的一面朝向玻璃窗片一侧，与固定腔镜平行设置构成激光谐振腔，二者间隔即谐振腔腔长；Independent cavity mirror: It is set apart from the laser gain tube mirror, and the side coated with the high reflective film faces the glass window side, and is set in parallel with the fixed cavity mirror to form a laser resonant cavity. The distance between the two is the length of the cavity; 光学玻璃片：设置在增益管玻璃窗片与独立腔镜之间，与谐振腔内的激光束倾斜成一定角度，包括靠近增益管一侧的第一平面，和靠近独立腔镜一侧的第二平面，两个平面镀增透膜；Optical glass sheet: It is set between the gain tube glass window and the independent cavity mirror, and is inclined at a certain angle to the laser beam in the resonant cavity, including the first plane on the side of the gain tube and the first plane on the side of the independent cavity mirror. Two planes, two planes are coated with antireflection coating; 所述致动器设置在激光经光学玻璃片的反射光路上，调整为可沿激光光束方向产生微位移；The actuator is arranged on the reflected light path of the laser passing through the optical glass sheet, and is adjusted to generate micro-displacement along the direction of the laser beam; 平面反射镜：设置在致动器朝向光学玻璃片一侧的端面，反射光学玻璃片第一平面和第二平面反射的两束光原路返回激光谐振腔；光学玻璃片与平面反射镜之间形成附属于激光谐振腔的分叉腔；Plane mirror: set on the end face of the actuator facing the optical glass sheet, the two beams of light reflected by the first plane and the second plane of the optical glass sheet are returned to the laser resonator in the same way; between the optical glass sheet and the plane mirror forming a bifurcated cavity attached to the laser resonator; 光电探测器：设置在固定腔镜远离独立腔镜的一侧，用于探测从固定腔镜输出的尾光，转变为随时间变化的电信号；Photodetector: set on the side of the fixed cavity mirror away from the independent cavity mirror, used to detect the tail light output from the fixed cavity mirror and convert it into an electrical signal that changes with time; 数据处理单元：与光电探测器相连，根据探测到激光分叉腔回馈时光强变化曲线，测得激光回馈条纹，计算致动器的位移与倾角；Data processing unit: connected with the photodetector, according to the detected light intensity change curve of the laser bifurcated cavity feedback, the laser feedback fringes are measured, and the displacement and inclination of the actuator are calculated; 所述位移为致动器在电源驱动下沿分叉腔中激光轴线方向上靠近或远离光学玻璃片的位移，所述倾角为相对激光轴线传播方向的角度变化。The displacement is the displacement of the actuator toward or away from the optical glass sheet in the direction of the laser axis in the bifurcated cavity under the driving of the power supply, and the inclination angle is the angular change relative to the propagation direction of the laser axis. 2.如权利要求1所述的微致动器位移及倾角测量装置，其特征在于：2. micro-actuator displacement and inclination measuring device as claimed in claim 1, is characterized in that: 所述数据处理单元被配置为，按如下方法计算致动器位移ΔL：The data processing unit is configured to calculate the actuator displacement ΔL as follows: ΔL＝λ/2(M+m)；ΔL=λ/2(M+m); 其中，λ为激光波长，M为回馈条纹整数部分，m为根据光强变化相位得到的回馈条纹小数部分，根据光电探测器探测的光强变化曲线获取；Among them, λ is the laser wavelength, M is the integer part of the feedback fringe, m is the fractional part of the feedback fringe obtained according to the change phase of the light intensity, and obtained according to the light intensity change curve detected by the photodetector; 所述数据处理单元被配置为，按如下方法计算致动器的倾角θ：The data processing unit is configured to calculate the inclination angle θ of the actuator as follows:
Figure FDA0003192488560000021
Figure FDA0003192488560000021
 其中：D为光束Er和光束Er'之间的距离，ε为微致动器位移和倾角引起的分叉腔长差系数，N为致动器伸缩过程中光强变化曲线中一个长周期包络下半波长波动的周期数；10800为弧度至角度的变换因子；Where: D is the distance between the beam Er and the beam Er' , ε is the length difference coefficient of the bifurcated cavity caused by the displacement and inclination of the micro-actuator, and N is a length in the light intensity change curve during the extension and contraction of the actuator. The number of cycles of the lower half-wavelength fluctuation of the periodic envelope; 10800 is the conversion factor from radians to degrees; Er为发射激光经增益管，在光学玻璃片第一平面F1反射至平面反射镜后，传播至平面反射镜处，再经过平面反射镜反射回激光谐振腔的光；Er'为发射激光经增益管，在光学玻璃片第一平面F1折射至第二平面F2，经第二平面F2反射至第一平面F1后，经第一平面F1折射出光学玻璃片，传播至平面反射镜处，再经过平面反射镜反射回谐振腔的光。E r is the light emitted by the emitted laser through the gain tube, after the first plane F 1 of the optical glass sheet is reflected to the plane mirror, then propagated to the plane mirror, and then reflected back to the laser resonator through the plane mirror; Er' is the emitted light The laser is refracted from the first plane F 1 of the optical glass sheet to the second plane F 2 through the gain tube, and after being reflected to the first plane F 1 by the second plane F 2 , the optical glass sheet is refracted through the first plane F 1 and propagated. to the plane mirror, and then the light reflected back to the resonator through the plane mirror. 3.一种微致动器位移及倾角测量方法，采用权利要求2中所述的测试装置，其特征在于，包括以下步骤：3. a kind of micro-actuator displacement and inclination angle measurement method, adopts the test device described in claim 2, is characterized in that, comprises the following steps: 计算致动器位移ΔL步骤：根据光电探测器图像获取激光回馈条纹的整数部分M和小数部分m；The step of calculating the actuator displacement ΔL: obtain the integer part M and the fractional part m of the laser feedback fringes according to the photodetector image; ΔL＝λ/2(M+m)；ΔL=λ/2(M+m); 计算致动器的倾角θ步骤：Steps to calculate the inclination angle θ of the actuator:
Figure FDA0003192488560000022
Figure FDA0003192488560000022
 其中：D为光束Er和光束Er'之间的距离，ε为微致动器位移和倾角引起的分叉腔长差系数，N为致动器伸缩过程中光强变化曲线中一个长周期包络下半波长波动的周期数；10800为弧度至角度的变换因子；Where: D is the distance between the beam Er and the beam Er' , ε is the length difference coefficient of the bifurcated cavity caused by the displacement and inclination of the micro-actuator, and N is a length in the light intensity change curve during the extension and contraction of the actuator. The number of cycles of the lower half-wavelength fluctuation of the periodic envelope; 10800 is the conversion factor from radians to degrees; Er为发射激光经增益管，在光学玻璃片第一平面F1反射至平面反射镜后，传播至平面反射镜处，再经过平面反射镜反射回激光谐振腔的光；Er'为发射激光经增益管，在光学玻璃片第一平面F1折射至第二平面F2，经第二平面F2反射至第一平面F1后，经第一平面F1折射出光学玻璃片，传播至平面反射镜处，再经过平面反射镜反射回谐振腔的光。E r is the light emitted by the emitted laser through the gain tube, after the first plane F 1 of the optical glass sheet is reflected to the plane mirror, then propagated to the plane mirror, and then reflected back to the laser resonator through the plane mirror; Er' is the emitted light The laser is refracted from the first plane F 1 of the optical glass sheet to the second plane F 2 through the gain tube, and after being reflected to the first plane F 1 by the second plane F 2 , the optical glass sheet is refracted through the first plane F 1 and propagated. to the plane mirror, and then the light reflected back to the resonator through the plane mirror. 4.如权利要求3所述的微致动器位移及倾角测量方法，其特征在于，所述方法进一步包括：4. The method for measuring displacement and inclination of a micro-actuator as claimed in claim 3, wherein the method further comprises: 在第一个角度计算获得第一组致动器的倾角数据；Calculate the inclination data of the first group of actuators at the first angle; 将致动器旋转90度，重复致动器倾角的计算步骤；Rotate the actuator by 90 degrees and repeat the steps of calculating the inclination of the actuator; 在第二个角度计算获得第二组致动器的倾角数据；Calculate the inclination angle data of the second group of actuators at the second angle; 结合第一组倾角数据和第二组倾角数据，获得致动器位移过程中实际倾角和倾斜方向。Combining the first set of inclination angle data and the second set of inclination angle data, the actual inclination angle and inclination direction during the displacement process of the actuator are obtained.
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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115117723A (en) * 2022-06-24 2022-09-27 中国科学院光电技术研究所 A cavity tuning method based on cavity mirror spot shape monitoring
CN115325943A (en) * 2022-08-18 2022-11-11 山东大学 High-resolution displacement measuring device and measuring method
CN120176980A (en) * 2025-05-21 2025-06-20 中国空气动力研究与发展中心超高速空气动力研究所 A method and device for measuring sideslip angle of wind tunnel test model
CN120294945A (en) * 2025-04-11 2025-07-11 中山大学 A high-precision small-angle generation device and method based on optical path folding and magnification

Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2002023120A2 (en) * 2000-09-13 2002-03-21 Gerhard Bonnet Optical device
CN1648682A (en) * 2005-01-26 2005-08-03 清华大学 Laser feedback nano displaycement measuring device
JP2006322820A (en) * 2005-05-19 2006-11-30 Fdk Corp Method and apparatus for measuring displacement of actuator
CN1888816A (en) * 2006-07-20 2007-01-03 清华大学 Extender high-light folding feedback displacement measuring system
CN1963384A (en) * 2006-11-21 2007-05-16 暨南大学 Method for measuring minute angle based on self-commix interference of laser and apparatus thereof
CN101021563A (en) * 2007-03-16 2007-08-22 清华大学 Double-refraction external cavity displacement measuring system
CN101261322A (en) * 2008-04-18 2008-09-10 清华大学 Dual Frequency He-Ne Laser Optical Feedback Rangefinder
CN102506715A (en) * 2011-10-13 2012-06-20 清华大学 Displacement data processing method based on microchip laser feedback interferometer
CN103471527A (en) * 2013-08-14 2013-12-25 北京镭测科技有限公司 Laser exocoel feedback low-angle roll angle measuring system
US20170025819A1 (en) * 2013-12-20 2017-01-26 Accelink Technologies Co., Ltd. Broadband Tunable External-Cavity Laser Using Small Mems Mirror
CN109813227A (en) * 2017-11-20 2019-05-28 中国人民解放军第四军医大学 Multiple feedback displacement measurement device and measurement method based on laser cavity tuning

Patent Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2002023120A2 (en) * 2000-09-13 2002-03-21 Gerhard Bonnet Optical device
CN1648682A (en) * 2005-01-26 2005-08-03 清华大学 Laser feedback nano displaycement measuring device
JP2006322820A (en) * 2005-05-19 2006-11-30 Fdk Corp Method and apparatus for measuring displacement of actuator
CN1888816A (en) * 2006-07-20 2007-01-03 清华大学 Extender high-light folding feedback displacement measuring system
CN1963384A (en) * 2006-11-21 2007-05-16 暨南大学 Method for measuring minute angle based on self-commix interference of laser and apparatus thereof
CN101021563A (en) * 2007-03-16 2007-08-22 清华大学 Double-refraction external cavity displacement measuring system
CN101261322A (en) * 2008-04-18 2008-09-10 清华大学 Dual Frequency He-Ne Laser Optical Feedback Rangefinder
CN102506715A (en) * 2011-10-13 2012-06-20 清华大学 Displacement data processing method based on microchip laser feedback interferometer
CN103471527A (en) * 2013-08-14 2013-12-25 北京镭测科技有限公司 Laser exocoel feedback low-angle roll angle measuring system
US20170025819A1 (en) * 2013-12-20 2017-01-26 Accelink Technologies Co., Ltd. Broadband Tunable External-Cavity Laser Using Small Mems Mirror
CN109813227A (en) * 2017-11-20 2019-05-28 中国人民解放军第四军医大学 Multiple feedback displacement measurement device and measurement method based on laser cavity tuning

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
张书练等: "激光回馈纳米级宽度干涉条纹", 《红外与激光工程》 *

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115117723A (en) * 2022-06-24 2022-09-27 中国科学院光电技术研究所 A cavity tuning method based on cavity mirror spot shape monitoring
CN115325943A (en) * 2022-08-18 2022-11-11 山东大学 High-resolution displacement measuring device and measuring method
CN115325943B (en) * 2022-08-18 2025-05-13 山东大学 High-resolution displacement measuring device and measuring method
CN120294945A (en) * 2025-04-11 2025-07-11 中山大学 A high-precision small-angle generation device and method based on optical path folding and magnification
CN120176980A (en) * 2025-05-21 2025-06-20 中国空气动力研究与发展中心超高速空气动力研究所 A method and device for measuring sideslip angle of wind tunnel test model

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