Switching and Fast Operation of Glow Discharge Detector for Millimeter Wave Focal Plane Array Imaging Systems

Applications of millimeter waves (MMWs), especially MMW imaging, are required in medicine, homeland security, communication, and space technology. The lack of a fast and inexpensive room temperature detector makes it difficult to realize those applications. Recently we found that the commercially available miniature neon lamps, known as glow discharge detectors (GDD), can be used as room temperature, sensitive, and inexpensive MMW detectors. Furthermore, they have shown a fast response time of about one microsecond. The disadvantages of using the GDD are high power consumption and for relatively large bias current, aging of the electrode coating due to electrode bombardment by heavy ions inside the plasma. Those disadvantages can be overcome by electronically switching on the detector bias current during detection period only, leaving the detector OFF most of the time. In this paper, the influence of the detector aging on the responsivity is investigated experimentally, and an electronic circuit for fast ON/OFF switching operation is demonstrated.