如何生成具有适当水平位差的左右眼平面图片是自由立体显示软件设计的核心问题。针对该问题，首先以双眼能够舒适地融合显示屏上的最大水平位差为依据，在Microsoft Direct 3D构建的3维模型空间体系内，寻找模型空间的视点与显示屏上水平位差之间的理论关系；然后，以视者在真实空间浏览3维模型真实感强、视觉舒适为原则来确定模型空间视点位置和投射表面平移量；最后，还提出了调整立体视觉效果的参数，并阐述了它们对立体视觉效果的影响机制。该研究成果已经投入使用，并获得了理想的立体视觉效果。

It is a crucial problem how to produce two pictures for left-eye and right-eye respectively with proper horizontal position disparity in autotereoscopic 3D display. The theoretic interrelation between the left-viewpoint and right-viewpoint in the model space by Direct 3D and the horizontal position disparity in the display screen has been established in this paper. The method for getting proper horizontal position disparity has been put forward aiming to provide proper sensation of depth as in real world and the most comfortable vision, and the theoretic formula is presented as well. Furthermore, two parameters, the position of left-viewpoint and fight-viewpoint in model world and the movement of the perspective plane, have been given in this paper, which directly affects the view result, The conclusions from this paper have gone into application and marvelous auto-stereoscopic 3D view has been achieved,