Study On Mechanical Display Characteristics Of LCD TV

The effect of electrically controlled birefringence of liquid crystal materials is used to display information.Under the certian voltage,the arrangement of the LC molecules,the birefringence of the LC,and the thickness of the LC cell have the direct influence on the transmittance of a LCD.In order to meet the needs of the market,LCD TVs become more and more larger and lighter.As the fact that the thinner glass substrates have to bear more heavier weight and the worser heat dissipation,the upper and lower glass substrates may perform inconsistent deformation due to different thermo-mechanical parameters of the various components in a LCD.As a result,the transmittance of light with different wavelengths varies with different trends,leading to display Mura.It is therefore necessary to carry out in-depth study on the mechanical display characteristics of large-size LCD TVs.The structure of a LCD panel is very complicated and it is difficult to obtain the substrate deformation and the transmittance variation by the direct test method.Therefore,this paper proposes a method combining experimental and simulation to explore the mechanical display characteristics of liquid crystal panels.Firstly,the mechanical tests are performed on the common LCDs and the bonding LCDs to observe the display phenomenon under different forces.Then the finite element analysis software ANSYS Workbench and the optical simulation software Tech Wiz LCD are employed to obtain the substrates deformation and the transmittance of three primary light.Finally,the threshold of the transmittance change that causes Mura display is obtained by comparing with the test results.The same simulation analysis method is used to analyze the influencing factors of LCD TV display characteristics,including LCD panel size,working temperature,installation method,and foam parameters.The results show that: the larger the size,the greater influence of gravity on the display characteristics of a LCD;as the temperature increases,the panel deformation and transmittance changes will increase dramatically.Therefore,it is necessary to effectively dissipate the heat of a LCD TV to ensure normal display.Selecting a foam with a large thickness and a small elasticity modulus can improve the Mura display.