LIQUID-CRYSTAL VARIABLE RETARDER USING LIQUID CRYSTAL CELLS OF DIFFERING THICKNESSES

• Main Author: ALEX HEGYI
• Format: Patent
• Language: English; Korean
• Published: 10.06.2019
• Subjects: ADVERTISING; ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICESUSING STATIC MEANS TO PRESENT VARIABLE INFORMATION; CRYPTOGRAPHY; DEVICES OR ARRANGEMENTS, THE OPTICAL OPERATION OF WHICH ISMODIFIED BY CHANGING THE OPTICAL PROPERTIES OF THE MEDIUM OF THEDEVICES OR ARRANGEMENTS FOR THE CONTROL OF THE INTENSITY,COLOUR, PHASE, POLARISATION OR DIRECTION OF LIGHT, e.g.SWITCHING, GATING, MODULATING OR DEMODULATING; DISPLAY; EDUCATION; FREQUENCY-CHANGING; NON-LINEAR OPTICS; OPTICAL ANALOGUE/DIGITAL CONVERTERS; OPTICAL LOGIC ELEMENTS; OPTICS; PHYSICS; SEALS; TECHNIQUES OR PROCEDURES FOR THE OPERATION THEREOF

A liquid crystal variable retarder has first and second liquid crystal cells with respective first and second thicknesses, wherein the second thickness is less than the first thickness. A feedback sensor provides a feedback signal indicative of retardance of the liquid crystal variable retarder. A controller is coupled to the feedback sensor and the first and second liquid crystal cells. The controller is operable to apply a first signal to the first liquid crystal cell based on a target retardance trajectory and a feedforward control model. The controller applies a second signal to the second liquid crystal cell based on the feedback signal and the target retardance trajectory. 액정 가변 지연자는 각각 제 1 및 제 2 두께를 갖는 제 1 및 제 2 액정 셀을 가지며, 제 2 두께는 제 1 두께보다 작다. 피드백 센서는 액정 가변 지연자의 지연을 나타내는 피드백 신호를 제공한다. 제어기는 피드백 센서 및 제 1 및 제 2 액정 셀에 결합된다. 제어기는 타겟 지연 궤적 및 피드 포워드 제어 모델에 기초하여 제 1 신호를 제 1 액정 셀에 인가하도록 동작 가능하다. 제어기는 피드백 신호 및 타겟 지연 궤적에 기초하여 제 2 신호를 제 2 액정 셀에 인가한다.