Blur, Accommodation, and Vision

描述(申请人提供)：我们对视觉世界的主观印象是一切都在焦点上。摄影和摄影中的常见做法强化了这种印象，即在任何地方都能创造出聚焦的图像。然而，我们的主观印象是非常不正确的，因为视网膜图像的大部分都是明显模糊的。我们将研究模糊和眼睛的聚焦反应在感知距离和大小方面的使用。我们还将研究模糊和适应对观众疲劳的影响。有明确的证据表明，模糊会影响距离和大小感知。将开发一个概率模型，将模糊和其他线索中的信息合并在一起。该模型将通过将其行为与人类在一系列心理物理实验中的感知进行比较来进行评估和改进。其中一组实验将使用在摄影中开发的微缩效果。这些实验将确定模糊和眼睛的聚焦反应(调节)对感知的绝对距离的贡献。另一组实验将利用图像中两个区域之间边界模糊所包含的信息。这些实验将决定观察到的模糊、焦距和相对大小是否会影响对深度顺序的感知。双目视差得到的深度几何形状和模糊得到的深度几何形状基本相似。原则上，这两种线索提供了关于距离的互补信息，其中视差提供了更准确的注视点附近的信息，模糊提供了远离注视的更准确的信息。视差和模糊对感知距离和眼动控制的相对贡献将针对相对于观看者观看的不同位置进行测量。视网膜图像中的模糊量取决于环境中物体的绝对和相对距离以及观察者聚焦的位置。我们定义了“自然景深”的概念；这是正常人眼观察自然环境时，其他景深线索和模糊之间的适当关系。我们将确定人们是否对自然景深敏感，以及3D结构在偏离自然关系的图像中是否被误解。立体显示器在医学成像、外科训练和科学可视化等应用中得到了越来越广泛的应用。电影和电视行业也在迅速引入立体声技术。对于立体显示器，收敛和调节之间的正常关联被打乱。结果是一场融合与协调的冲突。冲突有几个不利后果，但最重要的无疑是不适和疲惫。我们将确定观看距离、屈光不正、年龄以及收敛-调节冲突的程度和迹象如何影响不适和疲劳。更好的理解将有助于立体声显示器的设计和这种显示器上显示的内容。 与公众健康相关：我们将研究眼睛的模糊和聚焦反应，以及其他深度信息来源如何影响3D布局的感知。这项拟议的研究基于严格的心理物理技术，对眼睛图像形成的几何基础和深度信息来源进行了深入分析，并建立了定量的概率模型。它将产生广泛的影响，因为它涉及到大量的学术和应用学科，包括感知心理学、视觉科学、医学成像、计算机图形学、摄影、电影摄影、人体工程学和艺术。

DESCRIPTION (provided by applicant): Our subjective impression of the visual world is that everything is in focus. This impression is reinforced by the common practice in photography and cinematography of creating images that are in focus everywhere. Our subjective impression, however, is quite incorrect because most parts of the retinal image are significantly blurred. We will examine the use of blur and the eye's focusing response in the perception of distance and size. We will also examine how blur and accommodation affect viewer fatigue. There is clear evidence that blur affects distance and size perception. A probabilistic model will be developed that incorporates the information in blur and other cues. The model will be evaluated and refined by comparing its behavior to human perception in a series of psychophysical experiments. One set of experiments will use miniaturization effects developed in photography. Those experiments will determine the contributions of blur and the eye's focusing response (accommodation) on perceived absolute distance. Another set of experiments will capitalize on the information contained in the blur of a border between two regions in an image. Those experiments will determine whether the plausibility of observed blur, focus distance, and relative size affect the perception of depth order. The geometries of depth from binocular disparity and depth from blur are fundamentally similar. In principle, the two cues provide complimentary information about distance, with disparity providing more precise information near the point of fixation and blur providing more precise information away from fixation. The relative contributions of disparity and blur to perceived distance and eye-movement control will be measured for various positions relative to where the viewer is looking. The amount of blur in the retinal image depends on the absolute and relative distance of objects in the environment and on where the viewer is focused. We define the concept of "natural depth of field"; this is the appropriate relationship between other depth cues and blur for a normal human eye viewing the natural environment. We will determine whether people are sensitive to natural depth of field and whether 3D structure is misperceived in images that deviate from the natural relationship. Stereo displays are becoming more widely used in applications such medical imaging, surgical training, and scientific visualization. The motion picture and television industries are also rapidly introducing stereo. With stereo displays, the normal correlation between vergence and accommodation is disrupted. The result is a vergence-accommodation conflict. There are several adverse consequences of the conflict, but the most important is undoubtedly discomfort and fatigue. We will determine how viewing distance, refractive error, age, and the magnitude and sign of the vergence-accommodation conflict affect discomfort and fatigue. A better understanding will aid the design of stereo displays and the content shown on such displays. PUBLIC HEALTH RELEVANCE: We will examine how blur and the focusing response of the eye, coupled with other sources of depth information, affect the perception of 3D layout. The proposed research is based on rigorous psychophysical techniques, thorough analyses of the geometry underlying image formation in the eye and sources of depth information, and quantitative probabilistic modeling. It will have broad impact because it is relevant to a large number of academic and applied disciplines including perceptual psychology, vision science, medical imaging, computer graphics, photography, cinematography, ergonomics, and art.