Design of receptacle laser diode modules with low reflection

Abstract

AbstractThis paper describes the configurations and properties of receptacle User diode modules for optical subscriber networks. In optical assemblies where a single mode fiber is coupled using a ball lens, internal reflection frequently takes place. To reduce the back reflection at the fiber end face, a glass plate physically contacted the head of a PC‐polished ferrule. Then the method to evaluate the physical contact between the fiber end face and glass plate was discussed. Inspection with a Newton ring has proved such physical contact to be an efficient method of assembling a glass plate. In addition, modules were fabricated applying the projection and YAG laser welding, both of which are advantageous in firmly coupling components. Then the stability of the output of modules at higher temperatures, the stability of the contact between the module and PC‐FC connector and the influences of temperature cycling and high‐temperature environment on the connector were investigated. It was found that the change in the optical output was small when the temperatures were 0, 25, and 85°C and that the optical output was stable after temperature cycling and a high‐temperature stress test. Therefore, it was concluded that this receptacle laser diode was suitable for the optical subscriber systems.