A new type of large-displacement actuator called RAINBOW (Reduced And Internally Biased Oxide Wafer) has been fabricated by the chemical reduction of PSZT antiferroelectric ceramics and its properties are investigated. It is found that PSZT is easily reduced and the optimal conditions for producing RAINBOW samples were determined to be 870 degrees C for 2-3 h. The AFE-FE phase transitions occur at a lower field strength in the RAINBOW actuators compared with normal PSZT actuators. Larger axial displacement (about 190 mu m) have also been obtained from the RAINBOW actuators by application of electric fields exceeding the phase switching level. However, the field-induced displacement of the RAINBOW actuator is dependent on the manner of application of load on the samples.