The Study Of Modal Electrode Bend Oriented Liquid Crystal Lens

Liquid crystal lens is an adaptive microlens with adjustable focal length electronic control.The principle is mainly rely on the birefringence characteristics of liquid crystal to form a lens effect,the alignment of the liquid crystal molecules in the lens can be adjusted to achieve the gradient refractive index distribution by tuning the applied driving voltage.The liquid crystal lens generate great applications in the field of portable optical devices due to the tunable drive voltage focusing,stable and compact structure,portable and easy to integrate.However,the problems of conventional liquid crystal lenses have gradually emerged as the demands for optoelectronic devices continuously increase,such as slower response speeds,larger driving voltages,and poorer large aperture imaging.Therefore,in view of the deficiencies of traditional liquid crystal lens,we proposes a modal electrode bend oriented liquid crystal lens combining with the modal electrode liquid crystal lens,which have frequency-adjusting lens effect and better large aperture imaging effect with the bend orientation of liquid crystal moleculars.Response speed of the liquid crystal lens can be improved with low driving voltage in modal electrode bend oriented liquid crystal lens.The specific research content is as following:1.A simple and fast calculation method is proposed to simulate the modal electrode bend oriented liquid crystal lens by combining the theory of liquid crystal continuum wth the resistance-capacitance equivalent circuit model of modal electrode liquid crystal lens.The effects of voltage and frequency of the liquid crystal lens and square resistance of the high-resistance film on optical path difference distribution and voltage distributionare investigated.According to the simulation results,the driving conditions of modal electrode bend oriented liquid crystal lens with driving voltage of 21 V and th frequency of 12-20k Hz are designed.2.In order to improve the lens effect and reduce the errors of optical path difference distribution between the modal electrode liquid crystal lens and the ideal parabola,the optical path difference distribution of the modal electrode liquid crystal lens is simulated and compared with the ideal parabolic optical path difference distribution by adjusting the square resistance values of the lens hole at different positionse,which is based on the regional change feasibility of the high-resistance film square-resistance in the actual process.The comparison results show that the simulated optical path difference distribution after adjusting the resistance is closer to the ideal parabolic optical path difference distribution.The effect of the modal electrode liquid crystal lens can be improved by adjusting the distribution of the circular hole square resistance.3.Experimental research is carried out on the basis of simulation.A mode electrodee liquid crystal lens with cell thickness of 23.6 ?mand a mode electrode with cell thickness of 24 ?m are prepared,and a drive deviee with continuously adjusts voltage and frequency is designed.The optical characteristics and response velocities of the modal electrode parallel oriented liquid crystal lens and modal electrode bend oriented liquid crystal lens are studied by means of comparative test and the experimental results are analyzed.The test results show that the modal electrode bend oriented liquid crystal lens has a good imaging effect.The focal length can be continuously varied from 30.3 cm to infinity.The response time of modal electrode bend oriented liquid crystal lens is 136 ms,which is 368 ms shorter than the parallel oriented liquid crystal lens with similar parameters.The response speed of modal electrode bend oriented liquid crystal lens is significantly improved because it effectively avoids the"backflow effect".