Research On Photonic Crystal Fiber Filled With Liquid Crystal And Its Characteristics

Optical devices play the important roles in the field of information detection instruments which used for exploring the unknown fields.It is significance to design new instruments to study the characteristics of optical devices.Photonic crystal fibers(PCFs)hold an indispensable and important position in the field of scientific,because of the flexible structure design and unique characteristics.PCF is not easy to be disturbed by the electromagnetic field of the outside world.However,this feature is also an important factor that restricts its application in electromagnetic measurement.Liquid crystals(LCs)are well known for its optical birefringence,good electromagnetic and temperature response.A new research field,photonic liquid crystal fibers(PLCFs),combines the advantages of PCFs and LCs,and breaks the limitations of their application fields.With the development of the theory research and application technology of PLCFs,a series of optical devices based on PLCFs have been designed,such as polarization filter,optical attenuator and so on.Therefore,the study of PLCFs has become a research focus,and the related scientific research has important academic value and application potential.The thesis focuses on the influence factors of the transmission characteristics of three kinds of filled structures of PLCFs,which include the full-filled PLCF,selective-filled PLCF and both-end-filled PLCF.This study provides feasible design schemes for the tunable optical sensors based on PLCFs.The details are described as follows:1.Based on the advantages of LCs and the antiresonant reflecting optical waveguides model,achieves the control of the transmission characteristics of PLCFs by changing the parameters of LCs and the outside conditions.And the influence of LC parameters on the transmission characteristics of PLCFs is studied in details.At the same time,the influence of the clearing point on the tuning characteristics of temperature and electric field of PLCFs is also analyzed through the experiments.The feasibility for the realization of the tunable bandgap sensors and temperature-controlled switch are studied.2.Based on the multihole structure of PCFs and optical birefringence of LCs,the control and optimization of the optical properties of PCFs can be achieved by changing the number and location of LC holes.By the technology of selective-filling the PCFs,the influence of the number and location of LC holes on the transmission characteristics of PLCFs is studied.Taking the two-hole-filled PLCF as the example,the influence of the position of the LC holes on its birefringence is experimentally and numerically investigated.3.Based on the antiresonant reflecting optical waveguides model and the fiber coupling theory,the both-end-filled PLCFs are proposed.The structures achieve multifunction of filtering,temperature controllable fiber switch and light beam splitter,or one-way filter According to the filling materials are the same or not,they are divided into selective-full-filled PLCFs and both-full-filled PLCFs.For the selective-full-filled PLCFs,the influences of the number of LC holes and the temperature on transmission characteristics of PLCFs are investigated.For the both-full-filled PLCFs,the working principle is studied,and the influence of the proposed PLCFs with different coupling lengths on the transmission characteristics is also measured and analyzed.The study shows a original design for the realization of multifunctional tunable optical devices.