【摘要】 基于光折变材料的二波耦合特性提出了一种新型的空气扰动探测方法。空气中的微扰导致入射到光折变材料中两束光的光程差发生改变,干涉条纹随之发生变化。由于光折变体相位栅建立时间比较长,体相位栅不能及时跟随干涉条纹发生变化,导致干涉条纹与体相位栅间的相移将随空气扰动信息的变化而变化。相移角的改变将导致瞬态能量转移,输出两束光的能量在瞬态能量转移作用下将实现对空气扰动信息的光调制,并且这种调制过程是一种差分调制方式。在接收端采用电差分检测方法便可解调出空气扰动信息。这种利用光折变体相位栅的差分探测方法在未来的探测领域将有广泛的应用前景。更多还原

【Abstract】 A novel method based on photorefractive(PR) two-wave mixing to detect air turbulence is presented.The air turbulence is modulated on the input pump and signal beams of a PR crystal,thus creating a phase fluctuation for the input beams.Such a phase fluctuation results in an intensity fluctuation in the output beams and the intensity fluctuation can be detected by measuring the differential signals between the two output beams.Our experimental demonstration shows that air turbulence can be detected effectively based on the process of PR two-wave mixing and an electrical differential detection.This method may be widely used in future detecting applications.更多还原