The relationship between the field emission lifetime and the surface treatment for carbon nanotube (CNT) cold cathodes, with additional pulse aging was investigated. The surfaces of CNT cold cathodes after screen printing and baking were treated by a KrF excimer laser or tape peeling. An additional pulse aging was performed by an application of high pulsed field during operation. The lifetime of the CNT cathodes before and after pulse aging was measured with initial current densities of 0.1 and 1 mA/cm(2) as a function of time. The field emission lifetime of a laser-treated cathode followed by pulse aging was much longer than that of a tape-peeled cathode. The lifetime of a laser-treated CNT cathode reached 100 h, corresponding to 100 000 h at a duty ratio of 1/1000. (C) 2009 American Vacuum Society. [DOI: 10.1116/1.3100222]