摘要:
A dual-frequency grating interferometer displacement measurement system, comprises a dual-frequency laser, an interferometer, a measurement grating and an electronic signal processing component. The measurement system realizes displacement measurement based on grating diffraction, optical Doppler effect and optical beat frequency theory. Dual-frequency laser light is emitted from the dual-frequency laser and split into reference light and measurement light via a polarization spectroscope. The measurement light is incident to the measurement grating to generate positive and negative first-order diffraction. The diffraction light and the reference light form a beat frequency signal containing displacement information about two directions at a photo-detection unit, and linear displacement output is realized after signal processing. The measurement system can realize sub-nanometer and even higher resolution and accuracy, and is able to measure long horizontal displacement and vertical displacement at the same time.
摘要:
A single degree of freedom vibration isolating device of a linear motor and a motion control method thereof. The vibration isolating device comprises a balance block, an anti-drifting driving unit, and a control unit. An upper surface of the balance block is connected to a stator of the linear motor, and a lower surface of the balance block is connected to a base. The anti-drifting driving unit is connected to the balance block for controlling the position of the balance block. Provided two motion control methods; inputting a second grating ruler signal to the control unit as feedback to perform variable stiffness and nonlinear control on the balance block; inputting a first and a second grating ruler signal to the control unit as feedback to obtain resultant centroid displacement signals of the rotor and the balance block to perform nonlinear anti-drifting control on the balance block.
摘要:
A displacement measurement system of heterodyne grating interferometer, comprises a reading head, a measurement grating and an electronic signal processing component. Laser light emitted from the laser tube is collimated, passes through the first polarization spectroscope, and then emits two light beams with an orthogonal polarization direction and an orthogonal propagation direction; the two light beams pass through two acousto-optic modulators and respectively generate two first-order diffraction light beams with different frequencies, which are later divided into reference light and measurement light; two parallel reference light beams form a beat frequency electric signal with positive and negative first-order diffraction measurement light respectively after passing through a measurement signal photo-electric conversion unit; the beat frequency signals are transmitted to the electronic signal processing component for signal processing, thus the output of linear displacement in two directions is realized.
摘要:
An optical grating phase modulator for a laser interference photoetching system is composed of a substrate, an optical grating, an electric motor and an optical grating positioner. The optical grating, the electric motor and the optical grating positioner are all mounted on the substrate. The optical grating is circular or rectangular, and adopt transmission or reflection type optical grating. A light beam is incident on the optical grating and generates diffraction, and when the electric motor drives the optical grating to continuously move relative to the incident light beam, diffracted light will generate a frequency shift, thereby realizing the phase modulation of the light beam. The optical grating phase modulator has the advantages of high phase modulation speed, high regulation precision and wide regulation range, thereby improving the whole performance of an interference photoetching system.
摘要:
A three-DOF (Degree of Freedom) heterodyne grating interferometer displacement measurement system comprises a dual-frequency laser, a grating interferometer, a measurement grating, receivers and an electronic signal processing component; the grating interferometer comprises a polarizing beam splitter, a reference grating and dioptric elements; the measurement system realizes displacement measurement on the basis of grating diffraction, the optical Doppler Effect and the optical beat frequency principle. Three linear displacements can be output by the system when the grating interferometer and the measurement grating perform a three-DOF linear relative motion. The measurement system can reach sub-nanometer and higher resolution and precision, and can simultaneously measure three linear displacements. The measurement system has the advantages of being environmentally insensitive, high in measurement precision, small in size, light in weight, and is capable of improving the overall performances of an ultra-precision stage of a lithography machine as a position measurement system for this stage.
摘要:
A single degree of freedom vibration isolating device of a linear motor and a motion control method thereof. The vibration isolating device comprises a balance block, an anti-drifting driving unit, and a control unit. An upper surface of the balance block is connected to a stator of the linear motor, and a lower surface of the balance block is connected to a base. The anti-drifting driving unit is connected to the balance block for controlling the position of the balance block. Provided two motion control methods: inputting a second grating ruler signal to the control unit as feedback to perform variable stiffness and nonlinear control on the balance block; inputting a first and a second grating ruler signal to the control unit as feedback to obtain resultant centroid displacement signals of the rotor and the balance block to perform nonlinear anti-drifting control on the balance block.
摘要:
A method for measuring the displacement of a planar motor rotor. The measuring method comprises: four magnetic induction intensity sensors are distributed on the planar motor rotor; sampled signals of the four distributed sensors are processed to obtain signals Bsx, Bcx, Bsy and Bcy and magnetic field reference values Bksx, Bkcx, Bksy and Bkcy; and X-direction displacement and Y-direction displacement can be measured respectively according to inequalities (I) and (II) by judgments, wherein Δx and Δy are X-direction displacement resolution and Y-direction displacement resolution respectively, and BM is the magnetic induction intensity amplitude of the magnetic field of said planar motor. The method provided by the invention is simple in calculation, can avoid calculation of a transcendental function and solve the quadrant judgment problem, is favorable to real-time high-speed operation and has a high engineering value. B ksx B cx - B kcx B sx B M 2 ≥ Δ x ( I ) B ksy B cy - B kcy B sy B M 2 ≥ Δ y ( II )
摘要翻译:一种用于测量平面电动机转子的位移的方法。 测量方法包括:四个磁感应强度传感器分布在平面电机转子上; 处理四个分布式传感器的采样信号以获得信号Bsx,Bcx,Bsy和Bcy以及磁场参考值Bksx,Bkcx,Bksy和Bkcy; 并且可以通过判断根据不等式(I)和(II)分别测量X方向位移和Y方向位移,其中&Dgr; x和&Dgr; y分别是X方向位移分辨率和Y方向位移分辨率, BM是所述平面电动机的磁场的磁感应强度振幅。 本发明提供的方法计算简单,可以避免超验函数的计算,解决象限判断问题,有利于实时高速运行,具有很高的工程价值。 B ksx B cx - B kcx B sx B M 2ß≥&Dgr; x(I)B ksy B cy-B kcy B sy B M 2ß≥&Dgr; y(II)
摘要:
A silicon wafer platform with anti-collision function comprises a silicon wafer platform body (1) and a cable platform (2). The cable platform (2) is mounted on one side of the silicon wafer platform. The silicon wafer platform comprises three airbags (3), four damping buffer elements (4) and an air source (6), the three airbags (3) being connected in series and respectively secured on the other three sides of the silicon wafer platform by an airbag support (5), two adjacent airbags (3) communicating with a gas pipeline by one damping buffer element (4), and the gas pipeline being secured on the cable platform (2) and communicating with the air source. When two silicon platforms collide, the collision is buffered by the airbags and the silicon wafer platforms are not bounced off.
摘要:
A method for measuring displacement of a large-range moving platform, comprising: arranging multiple beams of first measuring light parallel to one another and generated by an optical path distribution device and a position sensitive detector array in a certain manner, to ensure that at least one beam of first measuring light is detected by the position sensitive detector array when a moving platform is at any position of a moving area; a detection head array capable of determining whether a light beam is shaded being used for auxiliary measurement of a position of the moving platform; and determining a position of the moving platform that corresponds to the first measuring light measured by the position sensitive detector array, to calculate displacement of the moving platform. The method effectively enlarges a measurement range of the position sensitive detector array, and implements measurement of long range displacement of the moving platform.
摘要:
A dual-frequency grating interferometer displacement measurement system, comprises a dual-frequency laser, an interferometer, a measurement grating and an electronic signal processing component. The measurement system realizes displacement measurement based on grating diffraction, optical Doppler effect and optical beat frequency theory. Dual-frequency laser light is emitted from the dual-frequency laser and split into reference light and measurement light via a polarization spectroscope. The measurement light is incident to the measurement grating to generate positive and negative first-order diffraction. The diffraction light and the reference light form a beat frequency signal containing displacement information about two directions at a photo-detection unit, and linear displacement output is realized after signal processing. The measurement system can realize sub-nanometer and even higher resolution and accuracy, and is able to measure long horizontal displacement and vertical displacement at the same time.