窃听器是随着20世纪电子技术的飞速发展而出现的,并且不断地微型化和精密化。目前,窃听器种类繁多,或体积微小(甚至小于一粒米)或伪装性强,能隐藏在任何物体内,如:电话机、手表、钢笔、领带夹、各种办公用品、生活用品、工艺品、 With the rapid development of electronic technology in the 20th century, bugging devices have emerged and are continuously miniaturized and refined. At present, a wide range of bug, or small size (or even less than a grain of rice) or camouflage, can be hidden in any object, such as: telephone sets, watches, pens, tie clips, all kinds of office supplies, daily necessities, handicrafts ,