The cathodoluminescent characteristics (CL) of a spherical Y 2 O 3 :Eu phosphor screen were investigated for field emission display application. The phosphor screen as an anode plate was vacuum sealed (ϳ3 ϫ 10 Ϫ6 Torr) with 0.7 in. diagonal Si-based Mo tip field emitter array with 25 ϫ 25 pixels. It was prepared by electrophoretically depositing spherical Y 2 O 3 :Eu phosphors, which were synthesized by the aerosol pyrolysis method. The character image was displayed on this anode plate by an external driver circuit with PWM driving scheme. The CL brightness of 41 cd/m 2 with CIE chromaticity of x ϭ 0.649, y ϭ 0.346 could be obtained at 400 V anode voltage and 55 V gate voltage inducing a 48 A/cm 2 current density in the dc mode, corresponding to 0.63 lm/W. However, screen efficiency could be increased to 1.24 lm/W by reducing the charge dose on the screen, of which the operating conditions were of 400 V anode voltage and 60 Vp-p gate voltage inducing an average 30 A/cm 2 emission current density in 15% pulse mode. It was found that the electrical resistivity of the phosphor screen was the origin of a pool image of displayed character and even caused a sudden decrease of emission light. The charging effects of spherical Y 2 O 3 :Eu phosphors screen on the luminance under low voltage operation are examined in this work and the methodology for enhancing picture quality is discussed based on experimental observation.

FED panel system was successfully built up through the integration of a 0.7″ diagonal Si‐based Mo‐tip FEA with 25×25 pixels, Y2O3:Eu or ZnO:Zn phosphor screen, and vacuum sealing through an exhausting glass tube, including a getter. The panel system was driven by an external driver circuit having PWM driving scheme. Before character imaging, it was stabilized through tip aging by increasing slowly a pulse‐mode emission current and phosphor aging by a coulombic charging process. After aging, luminescent characteristics such as emission uniformity, charging and arcing phenomena were shown to be improved significantly.