Epoxy adhesives for optical element attachment in planar passive optical components

Optical elements are bonded to the planar housing with adhesive materials for applications in a non-hermetic package of integrated passive optical devices. Eight epoxy adhesives have been evaluated in order to select the most suitable adhesive for use in a high-speed, automated assembly production facility. Tests were performed to examine the angular alignment accuracy and to determine the long-term adhesion and stability of the epoxy bonded components. Our results show that a thixotropic epoxy having high green strength, minimal shrinkage on cure, low outgassing and high resistance to humidity environment is suitable for bonding optical elements for the application.