Lcd Shift The Theoretical And Applied Research Of The Phase Detector

Liquid-crystal-based phased array (LC-phased array) is a kind of programmable optical phased array which uses Liquid Crystal as the electro-optic material and forms periodic phase distribution under periodic applied voltages. LC-phased array represent an enabling new technology that makes possible simple, lightweight, optical sensors offering very precise stabilization, random-access pointing, programmable multiple simultaneous beams, a dynamic focus/defocus capability. A phase profile is imposed on an optical beam and the imposed phase profile steers, focuses, fans out, or corrects phase aberrations on beams. LC-based phased arrays, which can be implemented using liquid crystals to produce the phase shift, require very little prime power, random-access, rapid beam pointing with no moving parts, thereby opening up application areas such as missile interceptors, satellite communications, and portable sensors of all types.In this dissertation, I design and fabricate a Liquid phased array based on the principle of Liquid Crystal grating, which can modulate the phase distribution of the incident light, for the electro-optic character of Liquid Crystal, through the computer programming and finally realize steering. Each electrode of the Liquid Crystal phased array can be controlled separate and can come into being random phase by programming, which is totally different from traditional Liquid Crystal grating. Here deflecting a beam is accomplished by forming phase distribution that similar to binary grating phase's through modulating applied voltages.Firstly, a practical model is set up according to the theory of binary grating. Based on binary optics and coupling wave optics with liquid crystal director calculation, LC-based phased arrays'diffraction efficiency of different orders is derived under kinds of step-shaped voltages. Using Matlab simulate the performance of the device, including steering angle, steering efficiencies, OPD and so on.Secondly, Based on the calculation of relative theory, a real LC-based phased array is realized through coating kinds of function thin films, lithographic patterning of an electrical addressing network and banding driving IC which provide voltages on the ITO glass substrate. Thirdly, built the testing system and test the quality of Liquid Crystal phased array. Testing experiments prove that LC-based phased array can realize the function of scanning, random-access pointing and programmable moderate to excellent optical power handling capability. At the same time, testing reveal some problems in the production process. Some new methods are employed in the production process later, aiming at solving the problems revealed from the testing and ameliorating performances of the device.