发光光弹性涂层折射率测量方法

涂层的折射率是发光光弹性涂层方法采用斜射法应变分离时不可缺少的参数之一. 通过对发光光弹性涂层受斜入射光波激发时, 发射光波沿入射光波原路径返回振幅变化的理论分析, 提出一种基于发光涂层光学菲涅耳响应的折射率在线测量方法. 实验测量了罗丹明B为发光染料的发光光弹性涂层在入射角为60°、波长为465 nm光波激发下的涂层折射率. 测量结果表明: 新的折射率测量方法是可行的, 对于其他用途的发光涂层折射率测量同样适用. 关键词： 折射率 光学测量 光学涂层 光致发光

Measurement of refractive index of luminescent photoelastic coating

The refractive index of the coating is one of the essential parameters used for principal strain separation in luminescent photoelastic coating (LPC) method by oblique incidence technique. According to the theoretical analysis of the amplitude of the emitted light exciting the coating, which returns along the same path as the oblique incident excitation light, we propose a new online method of measuring the refractive index of the LPC based on optical Fresnel response of the coating. The refractive index of the coating containing Rhodamine B as luminescent dye, is measured under the excitation at a wavelength of 465 nm and an incident angle of 60°. The experimental result proves the feasibility of the new method, and the present method is also applicable to the refractive index measurement of other luminescent coating.