利用漫反射式红外传感器、数字编/译码集成电路、专用电源系统以及LED数码管等器件，设计了一种通信井红外报警监控系统。当某个或某些井盖被揭起或移动时，红外接收端接收不到漫反射红外光信号。此时，监控模块将会输出报警信号脉冲，各自对应的井盖指示灯以红色闪烁显示，并发出报警信号，提醒值班人员注意，同时显示井盖号。由于该系统采用了数字编码技术，通过一台PC监控主机便可监控多个报警点。整体装置采用模块化结构，具有对光容易、工作稳定和免调试等特点。该报警监控系统己经在某机场通信网络公司得到了应用。

An infrared alarm monitor system for communication wells is designed. The system is consisted of diffuse infrared sensors, integrated circuits with digital coding and decoding functions, a special power supply and a LED digital display etc.. When one or some well covers are opened or removed, the infrared receiving module of the monitor system can not receive any diffuse infrared signals. At this moment, the monitor module outputs alarm signal pulses. Then, each corresponding indicator ?ickers and displays the number of the wells. Because the digital coding technique is incorporated, multiple places can be monitored via one master PC monitor. The whole system adopts a modular structure and has the features of easy light alignment, stable operation and free debug etc.. It has been used in an airport communication network.