AbstractThe luminance and luminous efficiency of Ne + Xe gas mixture in an AC PDP were investigated as a function of sustain gap according to Xenon concentration. The discharge characteristics of Ne+13%Xe gas‐mixture were compared with those of Ne+4%Xe when sustain gap was varied and the height of barrier rib was fixed. The luminance of Ne+13%Xe gas‐mixture discharge increased with an increase in sustain voltage until sustain gap was 300μm. The luminance and luminous efficiency of Ne+13%Xe gas‐mixture discharges in 500μm sustain gap were much lower than those in 80∼300μm sustain gap.