激光技术
激光技術
격광기술
LASER TECHNOLOGY
2015年
4期
501-505
,共5页
激光技术%激光反馈干涉%相位凝固技术%调制解调%重构%微位移测量
激光技術%激光反饋榦涉%相位凝固技術%調製解調%重構%微位移測量
격광기술%격광반궤간섭%상위응고기술%조제해조%중구%미위이측량
laser technique%laser feedback interference%phase freezing technique%modulation and demodulation%reconstruction%micro-displacement measurement
为了进一步减小基于相位凝固技术的激光反馈干涉系统测量运动物体微位移时的测量误差，采用MATLAB数值仿真及曲线拟合的方法，对移相间隔和外腔反射面振动幅度引起的系统误差进行了理论分析。在系统实验中依据相位凝固原理对物体运动产生的干涉信号进行采样，获取多组光功率曲线，在光功率曲线上实时判向并标记特征点。根据特征点重构被测物体的微位移曲线，对重构得到的微位移台阶曲线进行多项式拟合以提高测量精度。结果表明，在固定移相间隔为π／5、激光器波长为1550nm的情况下，测量分辨率优于λ／20（77．5nm），实际测量的绝对误差最大值为47．98nm，峰峰值误差平均值小于1nm。相位凝固技术调制解调干涉信号为微位移的方向辨识和高精度测量提供了新的解决方案。
為瞭進一步減小基于相位凝固技術的激光反饋榦涉繫統測量運動物體微位移時的測量誤差，採用MATLAB數值倣真及麯線擬閤的方法，對移相間隔和外腔反射麵振動幅度引起的繫統誤差進行瞭理論分析。在繫統實驗中依據相位凝固原理對物體運動產生的榦涉信號進行採樣，穫取多組光功率麯線，在光功率麯線上實時判嚮併標記特徵點。根據特徵點重構被測物體的微位移麯線，對重構得到的微位移檯階麯線進行多項式擬閤以提高測量精度。結果錶明，在固定移相間隔為π／5、激光器波長為1550nm的情況下，測量分辨率優于λ／20（77．5nm），實際測量的絕對誤差最大值為47．98nm，峰峰值誤差平均值小于1nm。相位凝固技術調製解調榦涉信號為微位移的方嚮辨識和高精度測量提供瞭新的解決方案。
위료진일보감소기우상위응고기술적격광반궤간섭계통측량운동물체미위이시적측량오차，채용MATLAB수치방진급곡선의합적방법，대이상간격화외강반사면진동폭도인기적계통오차진행료이론분석。재계통실험중의거상위응고원리대물체운동산생적간섭신호진행채양，획취다조광공솔곡선，재광공솔곡선상실시판향병표기특정점。근거특정점중구피측물체적미위이곡선，대중구득도적미위이태계곡선진행다항식의합이제고측량정도。결과표명，재고정이상간격위π／5、격광기파장위1550nm적정황하，측량분변솔우우λ／20（77．5nm），실제측량적절대오차최대치위47．98nm，봉봉치오차평균치소우1nm。상위응고기술조제해조간섭신호위미위이적방향변식화고정도측량제공료신적해결방안。
In order to reduce measurement errors with a laser feedback interference system measuring micro displacements of moving objects based on phase freezing technique , system errors induced by intervals of phase shift and vibrating amplitudes of reflecting surface were analyzed theoretically by means of MATLAB numerical simulation , interpolation and curve fit .In system experiments , interference signals produced by moving objects were collected and sampled by phase freezing principle so as to obtain multiple curves of optical power .Feature points were marked on the optical power curves to judge moving direction and reconstruct micro-displacement curves .Polynomial fitting based on the reconstructed micro displacement curves improved system measurement precision . Experimental results show that measurement resolution is superior to λ/20 (77.5nm) when fixed interval of phase shift is π/5 and wavelength of laser is 1550nm.The maximum absolute error of actual measurement of micro-displacements is 47.98nm and the average value of peak-peak errors is less than 1nm.Phase freezing technique provides a new solution for laser feedback interferometer system to identify directions and realize high precision measurement of micro-displacements .
