Written by a senior industry expert with nearly 40 years of hands-on experience, this book demonstrates how to improve photoluminescent (PL) and cathodoluminescent (CL) phosphor display devices in terms of energy efficiency, image quality, color fidelity, operational lifetime, and production cost. The text relates luminescence phenomena and color to chemical composition, excitation mechanisms, energy conversion efficiencies, and bulk properties of phosphor particles. It addresses image quality issues, powder deposition techniques, and the production of phosphor powders. It also explores promising developments for future phosphor display devices, such as nano-phosphor powders and flat CL displays.