A lamination study of a composite LCD flat panel display

Historically, the research and development for large flat panel displays has focused on gas plasma devices. Another type of display under consideration uses a series of individual LCD panels to form a large monolithic display. The objective of this study involves the lamination of the tiles into a single composite assembly. A final cover is placed over a subassembly of tiles which when butted together, can vary in thickness by up to 25 microns. The attachment mechanism for this process uses a single sheet adhesive to set the initial gap thickness. A second layer of a liquid adhesive is used to compensate for geometry variations in the tiles. ne process of squeezing the cover onto the tiles is characterized in terms of the squeeze times, directionality, and void development. Two primary mechanisms were found involving the generation of voids and bubbles; the first relating to the out gassing of the volatile components in the adhesive and the second relating to entrainment or hydrodynamic mechanisms associated with squeeze flows and surface topology of the sheet adhesive.