In this study, the film stacks of foldable AMOLED display are analyzed and designed by finite element analysis (FEA). Controlling the position of neutral plane is one of the key designs for foldable AMOLED display. However, the use of optically clear adhesives (OCA) has a particular effect on the prediction of neutral plane. In the FEA, traction-separation law is chosen to describe the mechanical behavior of adhesives; also the material parameters and failure strength of adhesives are obtained by basic material tests in advance. A 5.99-inch WQHD prototype foldable AMOLED display has been successfully folded more than 100,000 times in dynamic and static mixing at 3mm inward folding radius without damages.

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In this study, the film stacks of rollable AMOLED display are analyzed and designed by FEA (finite element analysis). The control for the layer thicknesses and stiffness of film stacks are two of the key designs for rollable AMOLED display. Also, the use of OCA (optically clear adhesives) brings a particular effect to the setting of neutral plane. In the FEA, constitutive model of hyperelasticity is chosen to describe the mechanical behavior of adhesives since the nonlinear elastic behavior and large deformation characteristics of adhesives. A 7.4-inch WQHD prototype rollable AMOLED display has been successfully rolled up more than 15,000 cycles in dynamic at 10mm rolling radius without damages.

Mid-story isolation structure is developing from base isolation structures. As a complex structural system, the work mechanism of base isolation structure is not entirely appropriate for mid-story isolation structure, and the prolonging of structural natural period may not be able to decrease the seismic response of substructure and superstructure simultaneously. In this paper, for a four-story steel frame model, whose prototype first natural period is about 1s without seismic isolation design, the seismic responses and isolation effectiveness of mid-story isolation system with lead rubber bearing are studied experimentally by changing the location of isolation layer. Respectively, the locations of isolation layer are set at bottom of the first story, top of the first story, top of the second story and top of the third story. The results show that mid-story isolation can reduce seismic response in general, and substructure acceleration may be amplified.

Mid-story isolation structure is developing from base isolation structures. As a complex structural system, the work mechanism of base isolation structure is not entirely appropriate for mid-story isolation structure, and the prolonging of structural natural period may not be able to decrease the seismic response of substructure and superstructure simultaneously. In this paper, for a four-story steel frame model, whose prototype first natural period is about 1s without seismic isolation design, the seismic responses and isolation effectiveness of mid-story isolation system with linear natural rubber bearing and viscous damper are studied experimentally by changing the location of isolation layer. Respectively, the locations of isolation layer are set at bottom of the first story, top of the first story, top of the second story and top of the third story. The results show that mid-story isolation can reduce seismic response in general, and substructure acceleration may be amplified.