中文摘要：

传统的键盘鼠标交互方式将演讲者束缚在计算机周围，阻碍演讲者与听众作近距离的交流，操作起来有欠自然。为解决此问题，提出了一种在投影显示中采用光笔进行人机交互的系统。利用摄像头拍摄投影屏幕，通过实时检测、计算激光笔投影点的屏幕坐标从而改变光标的坐标位置，控制鼠标的移动，采用无线射频技术实现鼠标按键功能。同时提出了一种基于网格细分的屏幕坐标校准方法，根据三个一组的网格点插值计算其中的屏幕坐标。实践结果表明，该系统人机交互简单直观，定位精确，具有很高的应用价值。

英文摘要：

In order to solve the problem in traditional human-computer interactions with keyboard and mouse band speakers to the computer devices, a system which used laser pen for human-computer interaction in the projective display was presented. The movements of cursor were controlled by the projective points of laser pen. The functioning keys of the mouse were imitated by the functioning keys of the laser pen. A simple calibration method for precise coordinates was presented. The result shows that the operators can control the object on the projective screen by the laser pen directly and conveniently, and the system is of high value.