Luminescence characteristics of green phosphors were investigated for different dwell times and anode biases for optimal designing of field emission displays. At a medium anode voltage of 2.5 kV, the brightness was decreased steeply with a lower dwell time (a higher device resolution). At higher anode biases, however, the-brightness Was reduced slower than calculated from a given dwell time, Such a relationship between the brightness and the dwell times seems to be explained by excitation profile of phosphor at different anode biases. For high-resolution field emission displays, it is considered that an engagement of higher anode biases is more beneficial to excellent images in terms of brightness.