Optical Characterization of Eu3+ Doped and Undoped Sr2CeO4 PhosphorsThe typical blue phosphor Sr2CeO4 material was prepared by different routes and also synthesized by different techniquies such as Pechini’s method, high temperature solid–state reaction, citrate–gel/sol-gel method, microwave calcination method, combustion method, and microwave–accelerated hydrothermal method. The luminescent compound materials doped with Europium (Eu) have various luminescence features in different lattice parameters, which are important in fields of displays (FEDs), plasma display panel devices, lamps and  cathode ray tubes (CRTs) etc.  In this study, a rare earth material Eu doped Sr2CeO4 phosphors and undoped Sr2CeO4 were synthesized by the conventional solid–state reaction method and characterized by X–ray diffraction (XRD), scanning electron microscopy images (SEM) and radioluminescence (RL) measurements. The Undoped Sr2CeO4 has a broad band with a peak position around 500nm due to the charge transfer (CT) mechanism. The Eu is an excellent host lattice activator yielding a strong emission in comparison to the luminescence from the well–known Sr2CeO4. Strong red emission coming from the hypersensitive 5D0®7F2 transition of Eu3+ ion suggested the presence of the dopant ion in a structurally disordered environment. From the XRD data, the average crystallite sizes of undoped and Eu doped Sr2CeO4, calculated using the Scherer’s Formula are found to be 72nm and 73nm respectively.