Abstract In this paper, we present two effects of illusion-based virtual shadows on a real surface for optical see-through head-mounted displays without devices that selectively reduce or intercept light rays from the real scene. The virtual shadows are based on the simultaneous brightness-contrast illusion in which a central region surrounded by a lighter one is perceived as darker than one without such a lighter region. To display a virtual shadow, a virtual object with a real image texture is placed around the shadow region as the lighter region to provide a sense of a darker area. We conducted two kinds of experiments to validate the feasibility of our method. The first experiment showed that users tend to perceive the virtual shadow part as darker than the surrounding area with the same physical luminance. The second experiment provided evidence that there are cases in which the virtual shadows can improve the reality of virtual objects.

中文翻译：

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光学透视头戴式显示器上的阴影感应

摘要在本文中，我们展示了基于幻觉的虚拟阴影在真实表面上的两种效果，用于光学透视头戴式显示器，无需选择性地减少或拦截来自真实场景的光线的设备。虚拟阴影基于同时出现的亮度对比错觉，其中被较亮区域包围的中心区域比没有较亮区域的区域更暗。为了显示虚拟阴影，在阴影区域周围放置具有真实图像纹理的虚拟对象作为较亮区域，以提供较暗区域的感觉。我们进行了两种实验来验证我们方法的可行性。第一个实验表明，用户倾向于将虚拟阴影部分感知为比具有相同物理亮度的周围区域更暗。