Abstract: Registration is the key problem in augmented reality application systems.In this paper，an improved registration method is proposed using projection technique.It is composed of four procedures：detecting positions of markers and feature points，camera tracking using projection technique，calculation of the model-view matrix，and rendering the virtual objects.In the initial process，four points are specified to build the world coordinate system on which the virtual objects will be superimposed.In the registration process，projection technique is used to track the positions of feature points and calculate the model-view transformation for augmentation.This method can provide accuracy and real-time performance needed for general indoor augmented reality systems.

Key words: augmented reality, registration, projection, tracking

摘要： 注册技术是实现增强现实应用系统的关键问题之一。实现了一种利用投影技术改进了的注册方法。这种注册方法主要包含4个步骤：（1）检测标识和特征点的位置；（2）利用投影技术跟踪摄像机；（3）计算模型视图矩阵；（4）绘制虚拟物体。在初始阶段，指定4个点建立世界坐标系，虚拟物体将会被叠加到这个坐标系上；在注册过程中，利用投影技术跟踪特征点的位置，并计算用于增强的模型视图转换。这种注册方法可以为一般的室内增强现实系统提供所需的精确度和实时性。

关键词: 增强现实, 注册, 投影, 跟踪