WO2020052056A1 - 一种五自由度外差光栅干涉测量系统 - Google Patents

一种五自由度外差光栅干涉测量系统 Download PDF

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WO2020052056A1
WO2020052056A1 PCT/CN2018/115782 CN2018115782W WO2020052056A1 WO 2020052056 A1 WO2020052056 A1 WO 2020052056A1 CN 2018115782 W CN2018115782 W CN 2018115782W WO 2020052056 A1 WO2020052056 A1 WO 2020052056A1
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measurement
degree
light
freedom
interference signal
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PCT/CN2018/115782
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English (en)
French (fr)
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朱煜
张鸣
王磊杰
叶伟楠
杨富中
夏一洲
李鑫
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清华大学
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Priority to US17/275,651 priority Critical patent/US11525673B2/en
Publication of WO2020052056A1 publication Critical patent/WO2020052056A1/zh

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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
    • G01B9/00—Measuring instruments characterised by the use of optical techniques
    • G01B9/02—Interferometers
    • G01B9/02001—Interferometers characterised by controlling or generating intrinsic radiation properties
    • G01B9/02002—Interferometers characterised by controlling or generating intrinsic radiation properties using two or more frequencies
    • G01B9/02003—Interferometers characterised by controlling or generating intrinsic radiation properties using two or more frequencies using beat frequencies
    • 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
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B9/00—Measuring instruments characterised by the use of optical techniques
    • G01B9/02—Interferometers
    • G01B9/02015—Interferometers characterised by the beam path configuration
    • G01B9/02017—Interferometers characterised by the beam path configuration with multiple interactions between the target object and light beams, e.g. beam reflections occurring from different locations
    • G01B9/02019—Interferometers characterised by the beam path configuration with multiple interactions between the target object and light beams, e.g. beam reflections occurring from different locations contacting different points on same face of object
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B9/00—Measuring instruments characterised by the use of optical techniques
    • G01B9/02—Interferometers
    • G01B9/02015—Interferometers characterised by the beam path configuration
    • G01B9/02027—Two or more interferometric channels or interferometers
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B9/00—Measuring instruments characterised by the use of optical techniques
    • G01B9/02—Interferometers
    • G01B9/02055—Reduction or prevention of errors; Testing; Calibration
    • G01B9/0207—Error reduction by correction of the measurement signal based on independently determined error sources, e.g. using a reference interferometer
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B2290/00—Aspects of interferometers not specifically covered by any group under G01B9/02
    • G01B2290/60—Reference interferometer, i.e. additional interferometer not interacting with object
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B2290/00—Aspects of interferometers not specifically covered by any group under G01B9/02
    • G01B2290/70—Using polarization in the interferometer

Definitions

  • the invention relates to a grating measurement system, in particular to a five-degree-of-freedom heterodyne grating interference quantity system.
  • Interferometric systems are also widely used in production and scientific research due to their high accuracy.
  • Common interference systems include laser interferometry systems and grating interferometry systems, as well as heterodyne interferometry systems and homodyne interferometry systems.
  • the method used in the existing multi-degree-of-freedom measurement systems on the market is a distributed combination of multiple single-degree-of-freedom laser measurement systems. Install a multi-axis laser interferometer in one direction, change the direction of the measurement light by using a pyramid prism, then install a mirror on the side and the direction of light propagation, and finally use the displacement difference to achieve a six-degree-of-freedom measurement.
  • the measurement system has a multi-degree-of-freedom measurement.
  • the influence of environmental factors is small, and it can compensate the advantages of thermal drift noise and fiber transmission error.
  • the measuring system can measure two linear displacements and three rotation angles simultaneously, and the accuracy is nanometer and micro radian.
  • this measurement system has obvious advantages, and can be applied to precision measuring machines such as precision machine tools, three-dimensional measuring machines, and semiconductor testing equipment that require large stroke linear displacement and a certain rotation angle. It is especially applicable to the measurement of ultra-precision worktables of lithography machines.
  • a five-degree-of-freedom heterodyne grating interferometry system is characterized in that it includes a single-frequency laser and an acousto-optic modulator.
  • the single-frequency laser emits a single-frequency laser
  • the single-frequency laser After optical fiber coupling and beam splitting, it is incident on the acousto-optic modulator to obtain two linearly polarized lights of different frequencies, one of which is used as reference light and the other is used as measurement light
  • the interferometer lens group and measurement grating are used to combine the reference light and measurement
  • the light forms a measurement interference signal and a compensation interference signal
  • a plurality of optical fiber bundles respectively receives the measurement interference signal and the compensation interference signal
  • each of the optical fiber bundles has a plurality of multimode optical fibers, and respectively receives signals at different positions on the same plane
  • the interferometer lens group includes a spectroscopic prism, a right-angle prism, a quarter-wave plate,
  • the components of the interferometer mirror group are symmetrically distributed from top to bottom.
  • the beam splitting prisms are located on the upper and lower layers of the mirror group and are symmetrically distributed.
  • the polarization beam splitting prism is located on the middle layer of the mirror group, the refractive element is located on the top of the mirror group, and the light path is set at a 90 ° deflection.
  • the right-angle prism, the right-angle prism, the beam splitting prism, and the polarization beam splitting prism, and the measurement light and the reference light pass through the same path in the interferometer lens group.
  • the reference light is divided into three beams of reference light after being split by two beam splitter prisms and reflected by a right-angle prism, and the three beams of reference light are reflected by three polarizing beam splitter prisms in the middle as three-way interference signals;
  • the measurement light After being split by two beam splitter prisms and reflected by a right-angle prism, it is divided into three beams of measurement light; two of the three beams of measurement light are reflected by a polarizing beam splitter prism in order, a quarter-wave plate, and a refraction element, from the left and right sides of the refraction element to facilitate
  • the Trow angle is incident on the measurement grating, and the diffracted beam returns along the original optical path, and then passes through the 1/4 wave plate in turn.
  • the two polarization beam splitting prisms in the middle transmit, the two right-angle prisms reflect, and the two beams serve as reference signals for interference signals.
  • the third measurement light is reflected by the polarization beam splitting prism, a 1/4 wave plate, and after reflecting by the mirror, passes through the 1/4 wave plate again, transmitted through the polarization beam splitting prism, and reflected by two right-angle prisms. And interfere with the third beam of reference light as an interference signal to form a compensation interference signal.
  • the measurement grating performs two-degree-of-freedom linear motion and three-degree-of-freedom rotation motion relative to the interferometer lens group.
  • the interferometer mirror is symmetrically distributed up and down, and the measurement light and reference light travel the same path in the interferometer mirror.
  • the temperature drift error of the parallel displacement is automatically eliminated.
  • the temperature drift error of the vertical displacement is eliminated by compensating the interference signal.
  • the displacement of two linear movements is measured based on the principle of Doppler frequency shift, and the accuracy reaches nanometer level;
  • the measurement of three rotation angles is measured based on the principle of differential wavefront, and the measurement range of the rotation angle is 1mrad, and the accuracy reaches the level of microradians.
  • the compensation interference signal is one
  • the measurement interference signal is two.
  • the two measurement interference signals and one compensation interference signal are respectively received by the optical fiber bundle, and each optical fiber bundle has four optical fibers and four The optical fibers are located at different positions in the same plane, and are used to receive interference signals in four quadrants.
  • Each optical fiber bundle outputs four optical signals for a total of twelve optical signals.
  • the interferometry system further includes a photoelectric conversion unit and an electronic signal processing component, wherein the photoelectric conversion unit is configured to receive an optical signal transmitted by the optical fiber bundle and convert the optical signal into an electrical signal to be input to the electronic signal.
  • a processing component the electronic signal processing component receives the electrical signal, and is used to calculate a linear displacement and / or a rotational movement of the measurement grating.
  • the fiber transmission error of the measurement system can be compensated.
  • the measurement system is applicable to a laser interferometer, a grating interferometer, a heterodyne interferometer, and a homodyne interferometer.
  • the precision five-degree-of-freedom heterodyne grating interferometric measurement system has the following advantages: the measurement system can simultaneously achieve five-degrees-of-freedom measurement of two translational displacements and three rotation angles, and accuracy Nano and micro radian levels, respectively, the measurement system has the advantages of realizing multi-free measurement, simple and compact structure, high accuracy, wide measurement range, little influence by environmental factors, and can compensate for thermal drift noise and fiber transmission error; compared with the existing There are multi-degree-of-freedom interferometry systems, which can avoid the influence of geometric installation errors such as Abbe error and cosine error on accuracy, and can better meet existing measurement requirements.
  • the measurement system can compensate for errors caused by temperature drift through its symmetrical optical structure, and can compensate fiber transmission errors due to the presence of compensation interference signals.
  • the five-degree-of-freedom heterodyne grating interferometer displacement measurement system can also be widely used in applications requiring precise measurement of multi-degree-of-freedom displacements, such as precision machine tools, three-coordinate measuring machines, and semiconductor inspection equipment, especially suitable for ultra-precision lithography machines. The workpiece table is being measured.
  • FIG. 1 is a schematic diagram of a five-degree-of-freedom interferometry system of the present invention.
  • FIGS. 2 and 3 are schematic structural diagrams of an interferometer lens group according to the present invention.
  • FIG. 4 is a schematic cross-sectional view of an optical fiber bundle used in the present invention.
  • 1 single-frequency laser
  • 2 acousto-optic modulator
  • 3 interferometer mirror group
  • 4 one-dimensional planar reflection grating
  • 5 fiber bundle
  • 6 photodetector
  • 7 Electro signal processing unit
  • 31 beamsplitter prism
  • 32 right-angle prism
  • 33 1 / 4 wave plate
  • 34 reffractive element
  • 35 reflector
  • 36 polarization beamsplitter prism.
  • FIG. 1 is a schematic diagram of a five-degree-of-freedom heterodyne grating interferometric measurement system according to the present invention.
  • the five-degree-of-freedom heterodyne grating interferometry system includes a single-frequency laser 1, an acoustooptic modulator 2, an interferometer mirror group 3, a measurement grating 4, a fiber bundle 5, a photodetector 6, and electronic signal processing.
  • Unit 7 is a schematic diagram of a five-degree-of-freedom heterodyne grating interferometric measurement system according to the present invention.
  • the five-degree-of-freedom heterodyne grating interferometry system includes a single-frequency laser 1, an acoustooptic modulator 2, an interferometer mirror group 3, a measurement grating 4, a fiber bundle 5, a photodetector 6, and electronic signal processing.
  • Unit 7 is a schematic diagram of a five-degree-of-freedom heterodyne
  • the interferometer lens group 3 includes a spectroscopic prism 31, a polarization beam splitting prism 36, a refractive element 34, a quarter-wave plate 33, a reflecting mirror 35, and a right-angle prism 32.
  • the beam splitting prism 31 is preferably located at the upper and lower layers of the mirror group, and is preferably symmetrically distributed.
  • the polarization beam splitting prism 36 is located at the middle or middle position of the mirror group, the refractive element 34 is preferably located at the top of the mirror group, and a right-angle prism 32 is arranged at a 90 ° deflection of the optical path.
  • the prism 32 is preferably bonded to the dichroic prism 31 and the polarization dichroic prism 36. All components are preferably fixed by means of adhesion.
  • FIG. 4 is a schematic cross-sectional view of an optical fiber bundle according to the present invention.
  • each fiber bundle 5 contains four multimode fibers.
  • Four multimode fibers are located at different positions in the same plane, instead of the quadrant photodetector, and used to receive interference signals in the four quadrants.
  • the single-frequency laser 1 emits a single-frequency laser that is coupled by an optical fiber and splits and enters the acousto-optic modulator 2 to obtain two channels of polarized light of different frequencies.
  • the reference light is divided into three beams of reference light after being reflected by the two beam splitting prisms 31 and the right-angle prism 32.
  • the three beams of reference light are reflected by the three polarization beam splitting prisms 36 in the middle as three-way interference signals.
  • the two beam splitting prisms 31 split the light and the right-angle prism 32 reflected into three beams of measurement light; two of the three beams of measurement light are reflected by the polarization beam splitting prism 32 in sequence, the quarter-wave plate 33, and the refractive element 34, and then from the refractive element
  • the left and right sides are incident on the measuring grating 4 at the Littrow angle.
  • the diffracted beam returns along the original optical path, and then passes through the 1/4 wave plate 33 in turn.
  • the two polarization beam splitting prisms 36 in the middle transmit and the two right-angle prisms 32 reflect.
  • the third beam of measurement light is reflected by the polarization beam splitting prism 36, the 1/4 wave plate 33, and the reflection mirror 35, and then passes through 1 /
  • the 4-wave plate 33 is transmitted through the polarization beam splitting prism 32, and is reflected by the two right-angle prisms 32, and interferes with the third beam of reference light as an interference signal to form a compensation interference signal.
  • the two measurement interference signals and one compensation interference signal are respectively received through three optical fiber bundles 5, and each optical fiber bundle contains four multi-mode optical fibers.
  • the optical signals of four quadrants of the same interference signal are collected and received through the light beam 5.
  • the formed twelve signals are transmitted to the photodetector 6 to be converted into electrical signals, and then transmitted to the electronic signal processing unit 7 for processing.
  • the rotation angle information of the grating can be calculated based on the principle of differential wavefront. The obtained rotation angle compensates for the phase caused by the additional displacement, and then solves the two-degree-of-freedom linear motion.
  • the electronic signal processing unit 7 When the measurement grid 4 performs translational movements in the x-direction and z-direction with respect to the interferometer lens group 3, and three rotation angle movements, the electronic signal processing unit 7 will output a two-degree-of-freedom linear displacement and a three-degree-of-freedom movement rotation angle.
  • ⁇ x, y, z is the rotation angle of the grating relative to the interferometer lens group
  • x, z is the displacement of the grating relative to the interferometer lens group
  • ⁇ 1,2,3,4,5,6,7,8 is Reading values of the two measurement signals on the electronic signal processing card
  • ⁇ x, y, and z are calibration constants
  • ⁇ x ⁇ , and z ⁇ are additional displacement compensation phases
  • p is the grating pitch
  • ⁇ is the laser wavelength
  • ⁇ is Litero angle.
  • the measurement system and structural solution provided in the above embodiments can measure three rotation angles and two linear displacements simultaneously, and the system has high measurement accuracy.
  • the measurement accuracy of the rotation angle is micro-radian level, and the measurement accuracy of the linear displacement is nano-level.
  • the system is less affected by the environment. It uses a fiber optic bundle to simplify the optical path, while improving the anti-interference ability and system integration of the measurement system.
  • the optical structure of the system uses a symmetrical structure to compensate for errors caused by temperature drift.
  • This measurement system is applied to the displacement measurement of ultra-precision workpiece table of lithography machine. Compared with the laser interferometer measurement system, it can effectively reduce the quality and volume of the workpiece table, and greatly improve the dynamic performance of the workpiece table.
  • the overall performance of the workbench has been comprehensively improved.
  • the five-degree-of-freedom heterodyne grating interferometry system can also be applied to other multi-degree-of-freedom precision measurement occasions, such as precision machine tools, coordinate measuring machines, and semiconductor testing equipment.
  • the present invention is not limited to the above-mentioned embodiments, and adopts the same or similar structure as the above-mentioned embodiments of the present invention, and other structural designs obtained are all within the protection scope of the present invention.

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  • General Physics & Mathematics (AREA)
  • Instruments For Measurement Of Length By Optical Means (AREA)
  • Length Measuring Devices By Optical Means (AREA)

Abstract

一种五自由度外差光栅干涉测量系统，包括单频激光器(1)、声光调制器(2)，单频激光器(1)出射单频激光，单频激光经光纤耦合、分束后入射至声光调制器(2)得到两路不同频率的线偏振光，一路作为参考光，一路作为测量光；干涉仪镜组(3)和测量光栅(4)，用于将参考光和测量光形成测量干涉信号和补偿干涉信号；多束光纤束(5)，分别接收测量干涉信号和补偿干涉信号，每束光纤束(5)中有多根多模光纤，分别接收同一平面上不同位置处的信号。该测量系统具有测量精度高、测量范围大、对温漂不敏感、整体尺寸小等优点，可用作光刻机超精密工件台位置测量系统。

Description

一种五自由度外差光栅干涉测量系统
本申请要求于2018年9月13日提交中国专利局的申请号为201811066763.0、发明名称为“一种五自由度外差光栅干涉测量系统”的中国专利申请的优先权，其全部内容通过引用结合在本申请中。
技术领域
本发明涉及一种光栅测量系统，特别涉及一种五自由度外差光栅干涉量系统。
背景技术
由于技术发展和工业需求，在特定的大型精密加工装备的设计制造中，测量系统的精度成为了一种重要的技术指标。干涉测量系统由于其高精度也广泛应用于生产和科研等领域。常见的干涉系统包括激光干涉测量系统和光栅干涉测量系统，同时也有外差干涉测量系统和零差干涉测量系统。
目前已有激光干涉测量系统一般只能实现单自由度的位移测量，多自由度测量系统很少存在。就现有的商用激光干涉仪而言，测量精度通常为纳米量级，但在实际测量过程中，由于几何安装误差、热漂移误差以及周期非线性误差的影响，造成测量结果的精度下降。在实际的运动过程中，振动等其他环境因素导致的微小转角，会带来x方向和z方向位移测量的附加位移。随着测量精度、运动距离、实际速度等运动指标的不断提高，以及多自由度测量的需求不断上升，一个能实现多自由度测量、且测量范 围和精度等性能指标满足实际需求的测量系统的设计是有必要的。
针对上述问题，为了满足多自由度的测量要求，目前市场已有的多自由度测量系统采用的方法是多个单自由度激光测量系统分布式组合。在一个方向上安装多轴激光干涉仪，再利用角锥棱镜改变测量光的方向，然后在侧面和光传播方向上安装反射镜，最后利用位移差分，实现六自由度测量。利用该方法的有荷兰ASML公司美国专利US 6,020,964B2(公开日2000年2月1日)、日本Nikon公司美国专利US 6,980,279B2(公开日2005年12月27日)、美国Agilent公司美国专利US 7,355,719B2(公开日2008年4月8日)。这种分布式组合的干涉测量系统结构不紧凑、光学调试复杂，且需要多个测量信号，给信号处理带来困难，难以满足现在的测量需求。还有的多自由度测量方法是通过测量光斑的位置变化，采用多种探测器的组合使用实现多自由度的同时测量。上述的这些方法，其系统结构复杂，且实际的测量依赖具体的光路结构，并且测量精度依赖于探测器性能和环境因素，目前的转角测量精度一般为角秒量级，位移测量精度一般为微米量级，很少达到纳米级。
发明内容
根据目前技术方案的不足，以及超精密测量的需求，发明了一种五自由度外差光栅干涉测量系统，该测量系统具有实现多自由度测量，结构简单紧凑，精度高，测量范围广，受环境因素影响小，能补偿热漂噪声和光纤传输误差等优点。该测量系统能同时测量两直线位移和三转角，精度为纳米和微弧度。该测量系统相较于上述的多自由度测量系统，具有明显的优势，能应用于精密机床、三坐标测量机、半导体检测设备等需要大行程直线位移和一定转角的精密测量的场合。特别能运用于光刻机超精密工 件台的测量中。
本发明所采用的技术方案如下：一种五自由度外差光栅干涉测量系统，其特征在于：包括单频激光器、声光调制器，所述单频激光器出射单频激光，所述单频激光经光纤耦合、分束后入射至声光调制器得到两路不同频率的线偏振光，一路作为参考光，一路作为测量光；干涉仪镜组和测量光栅，用于将所述参考光和测量光形成测量干涉信号和补偿干涉信号；多束光纤束，分别接收所述测量干涉信号和补偿干涉信号，每束光纤束中有多根多模光纤，分别接收同一平面上不同位置处的信号；所述干涉仪镜组包括分光棱镜、直角棱镜、1/4波片、折光元件、反射镜、偏振分光镜。
进一步地，干涉仪镜组各部件上下对称分布，分光棱镜位于镜组上层和下层，且呈对称分布，偏振分光棱镜位于镜组中层，折光元件位于镜组顶端，在光路发生90°偏转处设置直角棱镜，直角棱镜与分光棱镜和偏振分光棱镜，测量光和参考光在所述干涉仪镜组里面所经过的路径相同。
进一步地，所述参考光经过两个分光棱镜分光、直角棱镜反射后分为三束参考光，三束参考光再经过中间的三个偏振分光棱镜反射后作为三路干涉信号；所述测量光经过两个分光棱镜分光、直角棱镜反射后分为三束测量光；三束测量光中的两束依次经过偏振分光棱镜反射，1/4波片，折光元件后，从折光元件左右两边以利特罗角入射到测量光栅，衍射后的光束沿原光路返回，再依次经过1/4波片，中间的两个偏振分光棱镜透射，两个直角棱镜反射，与两束作为干涉信号的参考光分别干涉形成两路测量干涉信号；第三束测量光经过偏振分光棱镜反射，1/4波片，反射镜反射后，再次经过1/4波片，通过偏振分光棱镜透射，两个直角棱镜反射，与第三束作为干涉信号的参考光干涉形成一路补偿干涉信号。
进一步地，所述测量光栅相对于所述干涉仪镜组作二自由度线性运动和三自由度转角运动。
进一步地，所述干涉仪镜上下对称分布，测量光与参考光在所述干涉仪镜里面所经过的路径相同，当解算二自由度线性位移时，平行方向位移的温漂误差自动消除，垂直方向位移的温漂误差通过补偿干涉信号消除。
进一步地，两线性运动的位移是基于多普勒频移原理测量的，精度达到纳米级别；三转角的测量是基于差分波前原理测量的，且转角测量范围为1mrad，精度达到微弧度级别。
进一步地，所述补偿干涉信号为一路，所述测量干涉信号为两路，两路测量干涉信号和一路补偿干涉信号分别经所述光纤束接收，每束光纤束中有四根光纤，四根光纤位于同一平面内的不同位置，用于接收四个象限的干涉信号，每束光纤束输出四个光信号，共十二路光信号。
进一步地，所述干涉测量系统还包括光电转换单元和电子信号处理部件，其中：所述光电转换单元用于接收所述光纤束传输的光信号并转换为电信号，以输入至所述电子信号处理部件；所述电子信号处理部件接收所述电信号，用以解算所述测量光栅的线性位移和/或转角运动。
进一步地，由于补偿干涉信号的存在，又可补偿测量系统的光纤传输误差。
进一步地，测量系统适用于激光干涉仪、光栅干涉仪、外差干涉仪、以及零差干涉仪。
与现有技术相比，本发明所提供的一种精密五自由度外差光栅干涉测量系统具有以下优点：该测量系统能同时实现两个平移位移和三个转角的五自由度的测量，精度分别为纳米和微弧度级别，该测量系统具有实现 多自由测量，结构简单紧凑，精度高，测量范围广，受环境因素影响小，能补偿热漂噪声和光纤传输误差的优点；相较于已有多自由度干涉测量系统，该测量系统能避免阿贝误差和余弦误差等几何安装误差对精度的影响，更能满足现有的测量需求。同时，该测量系统可以通过自身对称的光学结构从而补偿温漂引起的误差，由于补偿干涉信号的存在又可补偿光纤传输误差。该五自由度外差光栅干涉仪位移测量系统还可广泛应用于需要多自由度位移的精密测量的场合中，如精密机床、三坐标测量机、半导体检测设备，尤其适用于光刻机超精密工件台的测量中。
附图说明
图1为本发明一种五自由度干涉测量系统示意图。
图2、3为本发明的干涉仪镜组结构示意图。
图4为本发明所用的光纤束截面示意图。
图中，1——单频激光器，2——声光调制器，3——干涉仪镜组，4——一维平面反射光栅，5——光纤束，6——光电探测器，7——电子信号处理单元；31——分光棱镜，32——直角棱镜，33——1/4波片，34——折光元件，35——反射镜，36——偏振分光棱镜。
具体实施方式
下面结合附图对本发明的原理、优选结构和具体实施方式作进一步地详细描述。尽管已经对本发明的优选实施例进行了描述，但是应理解的是，本发明不应限制于这些优选的实施例，而是本领域技术人员可在权利要求所要求的精神和范围内对本发明进行各种变化和修改。
请参考图1，图1为本发明的五自由度外差光栅干涉测量系统示意图。如图1所示，该五自由度外差光栅干涉测量系统包括单频激光器1、声 光调制器2、干涉仪镜组3、测量光栅4、光纤束5、光电探测器6、电子信号处理单元7。
请参考图2、3，图2、3为本发明的干涉仪镜组结构示意图。如图2所示，干涉仪镜组3包括分光棱镜31、偏振分光棱镜36、折光元件34、1/4波片33、反射镜35、直角棱镜32。分光棱镜31优选位于镜组上层和下层，优选呈对称分布，偏振分光棱镜36位于镜组中层或中间位置，折光元件34优选位于镜组顶端，在光路发生90°偏转处设置直角棱镜32，直角棱镜32优选与分光棱镜31和偏振分光棱镜36贴合。所有元件之间优选均采用粘接的方式固定。
请参考图4，图4为本发明的光纤束截面示意图。如图4所示，每个光纤束5中含有四根多模光纤。四根多模光纤位于同一平面内的不同位置，替代象限光电探测器，用于接收四个象限的干涉信号，。
结合图1、图2详细说明测量系统的原理，单频激光器1出射单频激光经光纤耦合、分束后入射至声光调制器2得到两路不同频率的偏振光，一路作为参考光，一路作为测量光参考光经过两个分光棱镜31分光、直角棱镜32反射后分为三束参考光，三束参考光再经过中间的三个偏振分光棱镜36反射后作为三路干涉信号；测量光经过两个分光棱镜31分光、直角棱镜32反射后分为三束测量光；三束测量光中的两束依次经过偏振分光棱镜32反射，1/4波片33，折光元件34后，从折光元件34左右两边以利特罗角入射到测量光栅4，衍射后的光束沿原光路返回，再依次经过1/4波片33，中间的两个偏振分光棱镜36透射，两个直角棱镜32反射，与两束作为干涉信号的参考光分别干涉形成两路测量干涉信号；第三束测量光经过偏振分光棱镜36反射，1/4波片33，反射镜35反射后，再次经过1/4波片 33，通过偏振分光棱镜32透射，两个直角棱镜32反射，与第三束作为干涉信号的参考光干涉形成一路补偿干涉信号。
所述两路测量干涉信号和一路补偿干涉信号，分别经三个光纤束5接收，每束光纤束内部含有四根多模光纤，采集同一干涉信号四个象限的光信号，经光线束5接收所形成的十二路信号传输至光电探测器6转换为电信号，再传至电子信号处理单元7进行处理，利用得到的相位信息，基于差分波前原理即可解算出光栅的转角信息，根据所得转角对附加位移引起的相位进行补偿，再解算二自由度线性运动。所述测量栅4相对于干涉仪镜组3做x向和z向的平移运动，和三个转角运动时，电子信号处理单元7将输出二自由度线性位移和三自由度运动转角。
五自由度运动解算的表达式为
Figure PCTCN2018115782-appb-000001
Figure PCTCN2018115782-appb-000002
Figure PCTCN2018115782-appb-000003
Figure PCTCN2018115782-appb-000004
Figure PCTCN2018115782-appb-000005
式中θ x,y,z为光栅相对与干涉仪镜组的转角，x,z为光栅相对于干涉仪镜组的位移，φ 1,2,3,4,5,6,7,8为两路测量信号在电子信号处理卡的读数值，Γ x,y,z为标定常数，φ xθ,zθ为附加位移补偿相位，p为光栅的栅距，λ为激光波长，θ为利特罗角。
上述实施方式中给出的测量系统及结构方案能够同时测量三个转动角度和两个线性位移，系统测量精度高，转角的测量的精度为微弧度级， 线性位移的测量精度为纳米级。该系统受环境影响很小，采用光纤束使光路简化，同时提高测量系统的抗干扰能力和系统集成性，同时该系统的光学结构采用上下对称的结构，补偿温漂引起的误差。该测量系统应用于光刻机超精密工件台的位移测量，对比激光干涉仪测量系统，在满足测量需求的基础上，可有效的降低工件台质量和体积，大大提高工件台的动态性能，使工件台整体性能综合提高。该五自由度外差光栅干涉测量系统还可应用于其他多自由度精密测量的场合中，如精密机床、三坐标测量机、半导体检测设备。
本发明并不限于上述实施方式，采用与本发明上述实施例相同或相近的结构，而得到的其他结构设计，均在本发明的保护范围之内。

Claims (13)

  1. 一种五自由度外差光栅干涉测量系统，其特征在于：包括激光器(1)、声光调制器(2)，所述激光器(1)出射激光，所述激光经光纤耦合、分束后入射至声光调制器(2)得到两路不同频率的线偏振光，一路作为参考光，一路作为测量光；干涉仪镜组(3)和测量光栅(4)，用于将所述参考光和测量光形成测量干涉信号和补偿干涉信号；多束光纤束(5)，分别接收所述测量干涉信号和补偿干涉信号。
  2. 根据权利要求1所述的一种五自由度外差光栅干涉测量系统，其特征在于：每束光纤束(5)中包括多根多模光纤，分别接收同一平面上不同位置处的信号。
  3. 根据权利要求1或2所述的一种五自由度外差光栅干涉测量系统，其特征在于：所述干涉仪镜组(3)包括分光棱镜(31)、直角棱镜(32)、1/4波片(33)、折光元件(34)、反射镜(35)、偏振分光镜(36)。
  4. 根据权利要求3所述的一种五自由度外差光栅干涉测量系统，其特征在于：干涉仪镜组(3)各部件上下对称分布，分光棱镜(31)位于镜组上层和下层，偏振分光棱镜(36)位于镜组中层，折光元件(34)位于镜组顶端，在光路发生90°偏转处设置直角棱镜(32)，直角棱镜(32)分别与分光棱镜(31)和偏振分光棱镜(36)贴合，测量光和参考光在所述干涉仪镜组(3)里面所经过的路径相同。
  5. 根据权利要求1或4所述的一种五自由度外差光栅干涉测量系统，其特征在于：所述参考光经过两个分光棱镜(31)分光、直角棱镜(32)反射后分为三束参考光，三束参考光再经过中间的三个偏振分光棱镜(36)反射后作为三路干涉信号；
    所述测量光经过两个分光棱镜(31)分光、直角棱镜(32)反射后分 为三束测量光；
    三束测量光中的两束依次经过偏振分光棱镜(36)反射，1/4波片(33)，折光元件(34)后，从折光元件(34)左右两边入射到测量光栅(4)，衍射后的光束沿原光路返回，再依次经过1/4波片(33)，中间的两个偏振分光棱镜(36)透射，两个直角棱镜(32)反射，与两束作为干涉信号的参考光分别干涉形成两路测量干涉信号；
    第三束测量光经过偏振分光棱镜(36)反射，1/4波片(33)，反射镜(35)反射后，再次经过1/4波片(33)，通过偏振分光棱镜(32)透射，两个直角棱镜(32)反射，与第三束作为干涉信号的参考光干涉形成一路补偿干涉信号。
  6. 根据权利要求1所述的一种五自由度外差光栅干涉测量系统，其特征在于：所述测量光栅(4)相对于所述干涉仪镜组(3)作二自由度线性运动和/或三自由度转角运动。
  7. 根据权利要求1或4所述的一种五自由度外差光栅干涉测量系统，其特征在于：测量光与参考光在所述干涉仪镜(3)里面所经过的路径相同，当解算二自由度线性位移时，平行方向位移的温漂误差自动消除，垂直方向位移的温漂误差通过补偿干涉信号消除。
  8. 根据权利要求6所述的一种五自由度外差光栅干涉测量系统，其特征在于：线性运动的位移是基于多普勒频移原理测量的，精度达到纳米级别；转角的测量是基于差分波前原理测量的，且转角测量范围为1mrad，精度达到微弧度级别。
  9. 根据权利要求1或2所述的一种五自由度外差光栅干涉测量系统，其特征在于：所述补偿干涉信号为一路，所述测量干涉信号为两路，两路 测量干涉信号和一路补偿干涉信号分别经所述光纤束(5)接收。
  10. 根据权利要求9所述的一种五自由度外差光栅干涉测量系统，其特征在于：每束光纤束(5)中有四根光纤，四根光纤位于同一平面内的不同位置，用于接收四个象限的干涉信号，每束光纤束(5)输出四个光信号。
  11. 根据权利要求1所述的一种五自由度外差光栅干涉测量系统，其特征在于：所述干涉测量系统还包括光电转换单元(6)和电子信号处理部件(7)，其中：所述光电转换单元(6)用于接收所述光纤束(5)传输的光信号并转换为电信号，以输入至所述电子信号处理部件(7)；所述电子信号处理部件(7)接收所述电信号，用以解算所述测量光栅(4)的线性位移和/或转角运动。
  12. 根据权利要求1所述的一种五自由度外差光栅干涉测量系统，其特征在于：所述测量系统适用于激光干涉仪、光栅干涉仪、外差干涉仪、以及零差干涉仪。
  13. 根据权利要求1所述的一种五自由度外差光栅干涉测量系统，其特征在于：所述补偿干涉信号可补偿所述测量系统的光纤传输误差。
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CN117367327B (zh) * 2023-12-01 2024-03-29 上海隐冠半导体技术有限公司 一种五角棱镜垂直度检测系统及方法

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6657181B1 (en) * 1999-03-12 2003-12-02 Canon Kabushiki Kaisha Optical element used in compact interference measuring apparatus detecting plurality of phase difference signals
CN102906545A (zh) * 2010-03-30 2013-01-30 齐戈股份有限公司 干涉测量编码器系统
CN102944176A (zh) * 2012-11-09 2013-02-27 清华大学 一种外差光栅干涉仪位移测量系统
CN103322927A (zh) * 2013-06-19 2013-09-25 清华大学 一种三自由度外差光栅干涉仪位移测量系统
CN106152974A (zh) * 2016-06-20 2016-11-23 哈尔滨工业大学 一种外差式六自由度光栅运动测量系统
CN106813578A (zh) * 2015-11-30 2017-06-09 上海微电子装备有限公司 一种二维光栅测量系统
CN108106536A (zh) * 2017-11-13 2018-06-01 清华大学 一种平面光栅干涉仪位移测量系统
CN108627099A (zh) * 2018-07-02 2018-10-09 清华大学 五自由度外差光栅干涉测量系统

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7188954B2 (en) * 2003-03-14 2007-03-13 Victor Company Of Japan Limited Image displaying apparatus and color separating-combining optical system
CN103307986B (zh) * 2013-06-19 2016-03-30 清华大学 一种二自由度外差光栅干涉仪位移测量系统
CN207487599U (zh) * 2017-11-13 2018-06-12 清华大学 一种平面光栅干涉仪位移测量系统

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6657181B1 (en) * 1999-03-12 2003-12-02 Canon Kabushiki Kaisha Optical element used in compact interference measuring apparatus detecting plurality of phase difference signals
CN102906545A (zh) * 2010-03-30 2013-01-30 齐戈股份有限公司 干涉测量编码器系统
CN102944176A (zh) * 2012-11-09 2013-02-27 清华大学 一种外差光栅干涉仪位移测量系统
CN103322927A (zh) * 2013-06-19 2013-09-25 清华大学 一种三自由度外差光栅干涉仪位移测量系统
CN106813578A (zh) * 2015-11-30 2017-06-09 上海微电子装备有限公司 一种二维光栅测量系统
CN106152974A (zh) * 2016-06-20 2016-11-23 哈尔滨工业大学 一种外差式六自由度光栅运动测量系统
CN108106536A (zh) * 2017-11-13 2018-06-01 清华大学 一种平面光栅干涉仪位移测量系统
CN108627099A (zh) * 2018-07-02 2018-10-09 清华大学 五自由度外差光栅干涉测量系统

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112857207A (zh) * 2021-03-09 2021-05-28 哈尔滨工业大学 基于阵列式探测器的单光束三自由度零差激光干涉仪
CN112857207B (zh) * 2021-03-09 2022-12-16 哈尔滨工业大学 基于阵列式探测器的单光束三自由度零差激光干涉仪
CN114485419A (zh) * 2022-01-24 2022-05-13 重庆大学 基于相干接收机延迟自零差探测的激光线宽测量系统及方法
CN114485419B (zh) * 2022-01-24 2023-01-10 重庆大学 基于相干接收机延迟自零差探测的激光线宽测量系统及方法
CN114719758A (zh) * 2022-03-30 2022-07-08 合肥工业大学 基于涡旋光束微位移测量的误差处理与补偿系统及方法
CN114719758B (zh) * 2022-03-30 2023-08-22 合肥工业大学 基于涡旋光束微位移测量的误差处理与补偿系统及方法

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