- We have developed focal plan array (FPA) imagers based on very inexpensive miniature neon indicator lamp detectors called glow discharged detectors (GDDs). The novelty of this paper is a technique of calibration, which permits reliable imaging with such an inexpensive FPA. GDDs are commercial lamps, which lack uniformity as detectors. The technique developed in this paper cancels out differences in response between the FPA lamps caused by both nonuniformity of the MMW collimated beam, and nonuniformity of the GDDs and other components in the electronic circuit. Utilizing this method in the new imaging system unifies detector response. Results, shown with two types of sensor configurations (8$,times,$ 8 and 18$,times,$2 scanner array), indeed show better performances and improvement in visibility of details.