A large-area, full-colored field emission display panel prototype based upon carbonnanotube emitters is proposed. Its cathode and gate are on the same plane. The experiment shows that the emission efficiency of this display device can reach to 29.3%, which is well consistent with the results of the theoretic simulation. The trench between the cathode and gate was etched by laser beam. The carbon nanotube polymer used as field emitter is formed by water bath.Results of the simple structure and fabrication process can lead the triode structure display to practical applications.