The four-point bend test is one of the most popular strength testing methods used to test LCD panels. Traditionally, a panel is assumed to be either a monolithic piece of glass or two independent pieces of glass sliding against each other. This paper uses finite element analysis to show that a panel behaves like a monolithic piece of glass in the epoxy region (near the edges) but behaves like two pieces of glass at the center. Assuming a panel to be a monolithic piece of glass may overpredict the stresses by a factor of two at the center. Similarly, assuming a panel to be two pieces of glass may underpredict the stresses by a factor of two at the edges. During four-point testing of a panel, the stresses are not uniform in the load-span region and so finite element analysis is required to obtain an accurate stress distribution.
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