基于双偏振检测的反射率差分型生物传感器  

Reflectivity Difference Biosensor Based on Dual Polarization Detection

作　　者：李武男[1] 冯莹[1] 魏立安[1] 曹毓[1] 马相路[1,2] 

机构地区：[1]国防科学技术大学光电科学与工程学院,湖南长沙410073 [2]空军预警学院,湖北武汉430019

出　　处：《光学学报》2012年第F12期245-249,共5页Acta Optica Sinica

摘　　要：为进一步提高反射率差分型生物传感器的检测灵敏度，简化光学系统结构，降低传感单元制作难度，在现有理论的基础上，采用双偏振检测方法来实现反射率差分传感。其思路是用不同偏振态的光照射传感单元，测量接收端的反射率差分量，从而获得生物分子层的厚度。仿真结果表明，当二氧化硅的厚度增加113．m时，双偏振检测方法获得的反射率差分量为0．7988％；改变偏振光的入射角度，得到反射率差分量的最大值为0．9143％；当入射波长增加1nm时，反射率差分量减少了0．23％。该方法比周期性结构的传感单元具有更高的检测灵敏度，而且受光源波长漂移和加工误差的影响较小。In order to further improve the detection sensitivity, simplify the optical system structure and reduce the manufacturing difficulty of sensing unit, the method using dual polarization to achieve differential detection is adopted on the basis of the existing theory. With the incidence of different polarization onto the sensing unit, reflectivity difference is obtained, and the thickness of biomolecule can be calculated by the reflectivity difference. According to the simulation results, when the thickness of silicon dioxide increases 1 nm, the reflectivity difference obtained by dual polarization detection method is 0. 7988%. By changing the incidence angle of different polarization, the maximum of reflectivity difference is O. 9143%. When the incidence wavelength has an excursion for 1 nm, the reflectivity difference changes 0.23% compared with the initial condition. Compared with the sensing unit using periodic structure, the method has higher sensitivity and dull reaction to wavelength excursion and machining error.

关 键 词：生物光学 光学生物传感器 双偏振检测 反射率差分 

分 类 号：O439[机械工程—光学工程] TP212.3[理学—光学]