基于谐振的光压测量

Measuring light pressure based on mechanical resonance

在扭秤的基础上,提出结合机械共振、光杠杆和电磁阻尼的光压测量方法.在大气环境中,测量激光对镜片作用的平行分力,忽略垂直镜片的分力,从而将光压与辐射效应错开,无需真空处理.采用调制光驱动扭秤,使其发生共振,并通过测量扭秤的振动幅度,得到光压的大小.实验结果表明:采用该方法测得激光器在45°入射、功率为70 mW时,产生光压为4.2×10^(-5) Pa.对共振曲线进行频谱分析及光压测量值评估,证实实验结果可靠.

Based on torsion balance,combining with mechanical resonance,optical lever and electromagnetic damping,a measurement method of light pressure was put forward.Optical parallel force towards lens was measured and the vertical force was omitted in the atmospheric environment,which would stagger light pressure and radiation effect,not requiring vacuum conditions.The controlled laser drove the torsion balance to resonate.By measuring the amplitude of the torsion balance,the light pressure could be obtained.Experimental results showed that the light pressure was about 4.2×10^（-5） Pa when the incidence angle was 45°and the power was about 70 mW.The spectrum analysis of the resonance curve and the assessment of pressure measurement result confirmed the feasibility of the method.