The Applied Research Of The Temperature Controled Light Beam Deflection Based On Lithium Niobate Crystal

Lithium niobate crystal is a multi-functional material,including ferroelectric,piezoelectric,electro-optical,photorefractive properties,it has a very good thermal stability and chemical stability.The lithium niobate crystals grown by the pulling method are easy to process and have lower cost and larger growth size,which is an important functional material in the future.At present,the beam deflection phenomenon is more popular topics,the main use of the crystal effect of light beam deflection.Recently studied hot crystals mainly include KTN,LiNbO3,etc.and doped similar crystals.Lithium niobate crystal electro-optical deflection has also been studied,but that the lithium niobate dielectric constant is only 28.7,while the KTN crystal is 15000.Therefore,under the same conditions,in order to achieve the same deflection effect with other crystals,the voltage of lithium niobate crystal is 500 times the KTN crystal.Therefore,we consider the use of temperature field to achieve the crystal within the beam deflection.In this paper,we study the beam deflection of lithium niobate crystals under the condition of temperature field.We mainly study the experimental study on the beam deflection in different thicknesses,different positions and different electrode modes,and use the experimental results to design the optical switch and beam splitter two optics.It can be seen from the experimental results that the deflection angle inside the crystal increases with the increase of the applied voltage on the crystal.When the voltage applied to the crystal increases,the temperature field inside the crystal will also increase.In the experimental results,the deflection angle of the lithium niobate crystal with 1 mm thick upper and lower plating electrodes can reach more than 2 degrees to achieve one-dimensional deflection.At the same time,the comparison experiment of 1 mm thick single-sided plating electrode was studied.It was found that the deflection of the beam resulted in a two-dimensional change due to the change of the electrode,but the maximum deflection angle was only close to 1 degree.The deflection angle of the 3 mm thick electrode with two electrodes is similar to that of the 1 mm thick single-sided electrode.The deflection angle can be close to 1 degree.Due to the change of the crystal thickness,crystal can achieve two-dimensional deflection with the change of the incident position of the beam;On the basis of this,we compared the influence of the change of the electrode on the angle of the temperature field and the deflection of the beam.From the experimental results,it can be seen that the temperature field generated by the crystal decreases with the decrease of the electrode.Optical switch and beam splitter are two important optical devices in the field of optics.We use light field to achieve beam deflection experiment to realize optical switch,as well as one-dimensional and two-dimensional beam splitting.Experiments measure the power of each beam of optical switch and beam splitter.The experimental results are in good agreement with the theory.With the rotation of the half-wave plate,the intensity will also change.