For a long time, security technology involves many subject fields and a wide range. In the past, it has always used optoelectronics, electronics, computers and other subject technologies and equipment to form a security system. Therefore, it is an application technology of Optoelectronics and other subject technologies. In particular, photoelectric information technology disciplines, such as image sensors and anti-theft and fire detectors at the front end of the security system, mainly photoelectric imaging devices and photoelectric detection devices, and their terminals and invisible light sources are their electro-optic converters and light-emitting devices, as well as optical fiber, infrared light transmission, night vision and photoelectric image processing Identification and tracking system, etc. Therefore, security technology is essentially an applied science and technology of photoelectric information technology in security technology prevention system. Of course, computer technology is used in the control part of the security system, electronic technology is used in the circuit part, and mechanical technology is involved in the assembly and positioning of equipment and the design and manufacture of casing. Therefore, security technology can be said to be a multi-disciplinary edge and multi-disciplinary comprehensive application high-tech integrating optoelectronics, electronics, computers, communications and machinery. At present, the traditional disciplinary and professional boundaries will be more and more weakened. The cross penetration and integration of various high and new technologies will be the general trend of the future development of a new technology (such as security monitoring technology). Therefore, the designer of security monitoring system should pay close attention to the development of science and technology in various fields, constantly adopt advanced and mature technology and constantly enrich intelligent functions to improve the design of the system. It is worth pointing out that while comprehensively applying various new technologies, we must pay attention to the coordination of the three basic elements of detection, response and delay and the cooperation of the three basic means of technical defense, material defense and civil defense, so as to truly and effectively achieve the purpose of security. With the development of photoelectric information technology, microelectronics, microcomputer and digital video technology, security monitoring technology has changed from traditional analog to highly integrated miniaturization, digitization and networking, and is developing towards integration, high definition and intelligence. At present, security monitoring technology has moved from foreground management to background processing. In many digital video equipment, it will have the functions of image feature extraction, processing and recognition, such as motion detection and alarm, abnormal behavior detection and alarm of people and vehicles through image analysis, so as to make the security technology intelligent. At present, the security technology has changed from the classical mode of applying the technology of various disciplines to the modern intelligent mode required by the characteristics of the security technology with image processing, recognition and tracking as the core. The discipline of security technology has developed from the application technology of Optoelectronics and other disciplines to a special discipline technology. In particular, the 9 / 11 bombings in the United States and the British bombings have further promoted the birth and development of security technology.