Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Optical Heterodyne Interferometry Based on Capacitance Timing and Multi-stage Filtering to Eliminate Nonlinear Errors

A technology of nonlinear error and optical heterodyne interference, applied in the direction of using optical devices, measuring devices, instruments, etc., can solve the problems of complex system, large amount of calculation, poor real-time performance, etc.

Inactive Publication Date: 2016-01-13
CHANGCHUN INST OF OPTICS FINE MECHANICS & PHYSICS CHINESE ACAD OF SCI
View PDF6 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] In order to solve the technical problems existing in the existing laser heterodyne interferometry system, such as complex system, large amount of calculation, poor real-time performance, and inaccurate results, the present invention provides an optical heterodyne interferometry based on capacitance timing and multi-stage filtering to eliminate nonlinear errors The method can eliminate nonlinear errors or specific harmonic components of interference, and eliminate the need for precision optical adjustment devices and precise adjustment processes required to eliminate nonlinear errors, making this adjustment very easy, while greatly improving system performance and reducing cost

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Optical Heterodyne Interferometry Based on Capacitance Timing and Multi-stage Filtering to Eliminate Nonlinear Errors
  • Optical Heterodyne Interferometry Based on Capacitance Timing and Multi-stage Filtering to Eliminate Nonlinear Errors
  • Optical Heterodyne Interferometry Based on Capacitance Timing and Multi-stage Filtering to Eliminate Nonlinear Errors

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0055] The present invention will be described in further detail below in conjunction with the accompanying drawings.

[0056] The system that implements the phase detection based on the capacitor charging timing method, multi-stage resonance filtering and optical heterodyne interferometry for eliminating nonlinear errors by weighted superposition in 3-dimensional linear space of the present invention can be divided into an optical part and an electronic signal processing part. The principle of the optical part is as follows figure 1 As shown, on the basis of an original optical part, the present invention adds the part in the dotted line box in the figure. First, the working principle of the optical part of the original heterodyne interferometry system is described: the laser light is emitted by the laser 101, and enters the acousto-optic device 103 through the first part of the mirror 102, and is frequency-shifted and then emitted to the second part of the mirror 114, and th...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention belongs to the field of optical heterodyne interference, and discloses an optical heterodyne interference method for removing a non-linear error based on capacitance timing and multi-stage filtering. The method comprises the steps that at least three paths of signals are obtained from an optical path where non-linear error interference elements exist, phase angles, on signal frequency elements to be removed, of the periodic non-linear error interference elements of the at least three paths of signals are made to be different in a corresponding circumference angle range or in a corresponding circumference angle range after integral multiples of circumference angles are removed, meanwhile, signals are filtered through a multi-stage resonant filter in an analog electrical signal channel, a phase difference between each path of measuring signals and a reference signal is computed by the adoption of a capacitance charging timing method, and then displacement calculation, weighting and iterative calculation are conducted through analog-digital conversion so as to remove or restrain the interference elements conveniently. The optical heterodyne interference method for removing the non-linear error based on the capacitance timing and the multi-stage filtering can remove specific harmonic elements of the non-linear error or the interference, the regulation process is very easy, system performance is improved, and cost is reduced.

Description

technical field [0001] The invention belongs to the field of optical heterodyne interferometry (Heterodyne Interferometry) measurement, and in particular relates to an optical heterodyne interferometry method for eliminating non-linear errors based on a capacitor charging timing method and multi-stage resonance filtering without fine adjustment. Background technique [0002] The laser heterodyne interferometry system can be used to measure physical quantities such as displacement and length, and is one of the best nanometer measurement methods. The system converts the measured displacement into the frequency or phase change of the heterodyne signal, and then measures this change. Since the frequency of the heterodyne signal is much lower than the optical frequency, the photoelectric signal is easy to process and can be electronically fine-tuned. Points to achieve higher measurement resolution, the resolution can reach picometer (pm) or better. [0003] However, nonlinearity...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Patents(China)
IPC IPC(8): G01B9/02
Inventor 孙强李也凡郭帮辉张艳超吴宏圣
Owner CHANGCHUN INST OF OPTICS FINE MECHANICS & PHYSICS CHINESE ACAD OF SCI
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products