Near-eye light field display: Difference between revisions - VR & AR Wiki

Line 1:

[[File:Lightfields.jpg|thumb|Figure 1. Light fields (Image: fudzilla.com)]]

__NOTOC__

'''Near-eye light field display'''s introduce a light-field-based approach to near-eye displays. This allows for ~~thinner and lighter~~ HMDs capable of depicting accurate accommodation, convergence, and binocular-disparity [[depth cue]]s. The two human eyes perceive the world slightly differently. In the same way, light rays that enter the pupil at different location will encode a slightly different picture of the world being observed <ref name=”3”></ref> <ref name=”4”> Fattal, D. (2016). The ultimate guide to 3D technologies. Retrieved from https://thenextweb.com/insider/2016/04/23/guide-to-3d-tech/#</ref>. A light field is composed of all the light rays at every point in space travelling in every direction. It is a 4D data, since every point in three-dimensional space is attributed a direction. This concept came about in the 1990s as a solution to problems in computer graphics and vision <ref name=”5”> LightField Forum. Refocus your Eyes: Nvidia presents Near-Eye Light Field Display Prototype. Retrieved from http://lightfield-forum.com/2013/07/refocus-your-eyes-nvidia-presents-near-eye-light-field-display-prototype/</ref>. Near-eye light field displays must independently render light rays that are coming from every direction through every point in space in order to trigger accommodation. Sharp images from out-of-focus display elements are depicted by synthesizing these light fields that correspond to virtual scenes located within the viewer’s natural accommodation range (Figure 1). Lanman and Luebke (2013) mention that “conventional displays are intended to emit light isotropically. In contrast, a light ﬁeld display supports the control of tightly-clustered bundles of light rays, modulating radiance as a function of position and direction across its surface.” <ref name=”2”></ref> <ref name=”3”></ref> <ref name=”4”></ref>

'''Near-eye light field display'''s introduce a light-field-based approach to near-eye displays. This allows for HMDs capable of depicting accurate accommodation, convergence, and binocular-disparity [[depth cue]]s that are also thinner and lighter. The two human eyes perceive the world slightly differently. In the same way, light rays that enter the pupil at different location will encode a slightly different picture of the world being observed <ref name=”3”></ref> <ref name=”4”> Fattal, D. (2016). The ultimate guide to 3D technologies. Retrieved from https://thenextweb.com/insider/2016/04/23/guide-to-3d-tech/#</ref>. A light field is composed of all the light rays at every point in space travelling in every direction. It is a 4D data, since every point in three-dimensional space is attributed a direction. This concept came about in the 1990s as a solution to problems in computer graphics and vision <ref name=”5”> LightField Forum. Refocus your Eyes: Nvidia presents Near-Eye Light Field Display Prototype. Retrieved from http://lightfield-forum.com/2013/07/refocus-your-eyes-nvidia-presents-near-eye-light-field-display-prototype/</ref>. Near-eye light field displays must independently render light rays that are coming from every direction through every point in space in order to trigger accommodation. Sharp images from out-of-focus display elements are depicted by synthesizing these light fields that correspond to virtual scenes located within the viewer’s natural accommodation range (Figure 1). Lanman and Luebke (2013) mention that “conventional displays are intended to emit light isotropically. In contrast, a light ﬁeld display supports the control of tightly-clustered bundles of light rays, modulating radiance as a function of position and direction across its surface.” <ref name=”2”></ref> <ref name=”3”></ref> <ref name=”4”></ref>

Near-eye displays (NEDs) project images into a viewer’s eyes, creating a virtual image in their field of view. The image appears at a distance, and larger than the small display panel and optics used to create it. However, according to [[Doug Lanman]] and Luebke (2013), these kind of displays have a fundamental problem: the unaided human eye cannot accommodate (focus) on objects placed in close proximity <ref name=”1”> Bhakta, V.R., Richuso, J. and Jain, A. (2014). DLP ® Technology for Near Eye Display. Retrieved from http://www.ti.com/lit/wp/dlpa051/dlpa051.pdf</ref> <ref name=”2”> Lanman, D. and Luebke, D. (2013). Near-Eye Light Field Displays. ACM Transactions on Graphics, 32(6)</ref> <ref name=”3”> Stanford University. Near-Eye Light Field Displays. Retrieved from https://talks.stanford.edu/douglas-lanman-near-eye-light-field-displays/</ref>.