基于复琼斯矩阵的扭曲染料液晶调光器件的机理与性能研究OA

Owing to their unique physical properties,liquid crystals have evolved into an important category of optical modulation devices,and Dye-Doped Liquid Crystal(DDLC)serves as a critical technical route to achieve electrically tunable light intensity modulation.To tackle the lack of quantitative theoretical correlation between optical rotation and the coupling effect of dye anisotropic absorption in Twisted Nematic(TN)DDLC devices,this work established a complex Jones matrix theoretical model for TN liquid crystals with absorption losses,derived an analytical formula of dark-state transmittance for the light-modulating structure of single-layer TN cells integrated with a polarizer(TN+P),and systematically investigated how twist angles,liquid crystal cell gaps,dye absorption coefficients and birefringence modulate devices'optical performance.A closed-loop verification integrating theoretical calculation,Techwiz LCD 1D optical simulation and sample fabrication was carried out using commercial positive DDLC mixtures as the core functional material.Theoretical calculations revealed that twisted liquid crystal structures alter polarization evolution along the optical path,break the matching conditions for efficient dye absorption and thus induce dark-state light leakage,while high-birefringence materials enhance optical rotation and boost light absorption efficiency.The software simulations and contrast ratio viewing angle distributions further confirmed that twist angles increase dark-state transmittance and degrade device performance.Samples with cell gaps of 5,8,10 μm and twist angles ranging from 0° to 360° were experimentally fabricated.The measured results demonstrated that the TN+P device with a 10 μm cell gap and a 0° twist angle achieves optimal light-shielding performance with a dark-state transmittance as low as 1.03%;all 8 μm devices exhibit millisecond-scale fall times,and the 90° twisted structure exhibited the slowest fall time dominated by the twist elastic torque.This study refines the quantitative optical analysis system for twisted DDLC,providing a complete theoretical basis and experimental support for the structural design of DDLC-based smart windows and optical shutters with excellent light-shielding performance and continuous electrical tunability.