The organization of behavior: A neuropsychological theory

The computational brain: Patricia S. Churchland and Terrence J. Sejnowski (MIT Press, Cambridge, MA, 1992); xi, 544 pages, $39.95

Three-dimensional (3D) displays have become important for many applications including vision research, operation of remote devices, medical imaging, surgical training, scientific visualization, virtual prototyping, and more. In many of these applications, it is important for the graphic image to create a faithful impression of the 3D structure of the portrayed object or scene. Unfortunately, 3D displays often yield distortions in perceived 3D structure compared with the percepts of the real scenes the displays depict. A likely cause of such distortions is the fact that computer displays present images on one surface. Thus, focus cues-accommodation and blur in the retinal image-specify the depth of the display rather than the depths in the depicted scene. Additionally, the uncoupling of vergence and accommodation required by 3D displays frequently reduces one's ability to fuse the binocular stimulus and causes discomfort and fatigue for the viewer. We have developed a novel 3D display that presents focus cues that are correct or nearly correct for the depicted scene. We used this display to evaluate the influence of focus cues on perceptual distortions, fusion failures, and fatigue. We show that when focus cues are correct or nearly correct, (1) the time required to identify a stereoscopic stimulus is reduced, (2) stereoacuity in a time-limited task is increased, (3) distortions in perceived depth are reduced, and (4) viewer fatigue and discomfort are reduced. We discuss the implications of this work for vision research and the design and use of displays.

Vergence-accommodation conflicts hinder visual performance and cause visual fatigue.

Lasing in disordered media presents both theoretical challenges and practical opportunities.

/pdf/the-physics-and-applications-of-random-lasers-12d4cwd4vp.pdf

The physics and applications of random lasers

Binocular vision and ocular motility , Binocular vision and ocular motility , کتابخانه دیجیتال جندی شاپور اهواز

Binocular Vision and Ocular Motility

The variations in fixation disparity (FD) with spatial frequency and retinal locus of fusion locks were examined in two groups of subjects having either steep or flat forced-duction FD curves. FD for subjects with flat curves was unaffected by either spatial frequency or diameter of fusion locks. FD of observers with steep forced-duction curves increased with both the coarseness and eccentricity of fusion locks. Panum's horizontal fusion range increased markedly with target spatial period but only modestly with retinal eccentricity. These results indicate that factors other than the dimensions of Panum's fusional area (PFA) result in the increase of FD found in some observers with peripheral fusion locks.

Combined effects of spatial frequency and retinal eccentricity upon fixation disparity.

Changes in cyclotorsion and vertical eye alignment during prolonged monocular occlusion.

Purpose
The maximum binocular vertical disparity that can be fused with disparity vergence (vertical-fusion amplitude or VFA), varies with convergence angle VFA is larger for convergence responses to near than to far viewing distances; however the clinical norms for changes in VFA with convergence have not been established VFA at several convergence angles was measured to obtain a quantitative description of the changes in VFA with convergence

Variation of binocular-vertical fusion amplitude with convergence

A pulse-step model of accommodation dynamics in the aging eye.

http://schorlab.berkeley.edu/download/plasticity_convergence-dependent01.pdf

Clifton M. Schor

Papers

Combined effects of spatial frequency and retinal eccentricity upon fixation disparity.

Changes in cyclotorsion and vertical eye alignment during prolonged monocular occlusion.

Variation of binocular-vertical fusion amplitude with convergence

A pulse-step model of accommodation dynamics in the aging eye.

Plasticity of convergence-dependent variations of cyclovergence with vertical gaze.