光波导技术同步测量棱镜及波导薄膜参数

依据全反射理论和棱镜耦合原理，实现了对棱镜折射率及波导薄膜材料折射率和厚度的同步测量。使用高准直半导体激光器激光入射到棱镜内部与波导膜的分界面上,逐步旋转棱镜或改变棱镜的入射角，得到棱镜耦合M线，曲线前面几组的波谷为波导模激发，在M线左侧收尾处有一个不完整波峰，其反射光强随入射角迅速衰减，为全反射时的临界点，由此可实现棱镜及波导薄膜参数的同步测量；用此法测量了棱镜耦合一体化平面波导棱镜的折射率和聚甲基丙烯酸甲酯(PMMA)聚合物波导薄膜的折射率和厚度。测量棱镜折射率精度为±1.9×10-4，波导薄膜折射率和厚度的精度分别为±6.2×10-4 μm和±1.6×10-2 μm。

Simultaneous Measurement of Prism and Waveguide Film Parameters by Waveguide Technology

According to the principle of total reflection theory and the prism coupling, the simultaneous measurement of the refractive index of the prism and waveguide refractive index of film material and thickness are measured. Highly collimated diode laser is used to enter to the boundary surface of the waveguide film inside the prism, the prism coupler M line is obtained by gradually rotating the prism or changing the angle of incidence of the prism, the lines of previous trough are waveguide mode excitation in the M line ending at the left side there is an incomplete crest, its reflected light intensity decays rapidly with the angle of incidence, which is the total reflection critical point, by this the simultaneous measurement of the parameters of the prism and the waveguide film is realized; refractive index of the prism coupler integrated planar waveguide prism and the refractive index and thickness of the polymethylmethacrylate (PMMA) polymer waveguide film are measured with this method, measured prism refractive index accuracy is ±1.9×10－4. The accuracy of the waveguide refractive index and thickness are ±6.2×10-4 μm and ±1.6×10-2 μm respectively.