镀减反射膜后半导体激光器端面反射率谱的测量

Specifying the Variation of Reflectivity with Wavelength of a Semictinductor Diode Facet After AR Coated

比较相同偏置条件下镀减反射膜前后的半导体激光器端面自发辐射谱，测得了端面反射率随波长变化的关系曲线。该方法突破了Ｋａｍｉｎｏｗ法单一波长测量的限制，同时也避免了Ｋａｍｉｎｏｗ法在两端面镀膜后所遇到的调制度过小的问题。实验中确定出了低于８×１０（－５）的第二镀膜端面反射率。

Comparison between spectra from the facet of a semiconductor laser before andafter AR coated under the same bias condition has led to the establishment of the variationcurve of the facet reflectivity vs. the wavelength.,This method is applicable to a certainwavelength range, and overcomes the difficulty encountered when Kaminow's methodis implemented to determine the very low reflectivity of the diode with both facetS ARcoated.As a result, a reflectivity of less than 8×10-5 at the second coated facet has beenmeasured.