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At Stanford University<\/a>, electrical engineer Gordon Wetzstein leads the project, working with postdoctoral scholar Suyeon Choi and collaborators. <\/p>\n Their goal is to pass what colleagues call a Visual Turing Test<\/a>. This is a standard borrowed from computing<\/a>, in which a viewer cannot tell a natural object from a digitally created one.<\/p>\n Holographic glasses make better VR<\/p>\n Invented by Nobel laureate Dennis Gabor<\/a>, holography<\/a> stores both the brightness and timing of light waves, letting a flat surface rebuild a full three-dimensional wavefront. <\/p>\n Because every pixel bends light rather than just shining it, a holographic screen can place virtual objects at any distance without the eye strain that plagues stereoscopic displays.<\/p>\n \u201cThis technology offers capabilities that we can\u2019t get with any other type of display, in a package that is much smaller than anything on the market today,\u201d said Wetzstein. <\/p>\n The team chose holography not for novelty but to match human depth cues that require subtle phase information.<\/p>\n Current commercial<\/a> headsets imitate depth by sending separate images to each eye, but both eyes still focus on the same flat panel. Holography restores natural focusing. <\/p>\n A kitten can sit on your lap while a planet floats miles away, and each will appear crisp at its own distance.<\/p>\n How these holographic glasses work<\/p>\n Miniature lasers feed a micro electromechanical mirror that steers light into a custom waveguide that is only 0.02 inches (0.5 millimeters) thick. <\/p>\n Inside that glassy slab, volume Bragg gratings bounce and expand the beam before it exits toward a reflective spatial light modulator<\/a> that sculpts the final hologram.<\/p>\n The entire optical stack, from input face to eyepiece, measures just 0.12 inches (3 millimeters). <\/p>\n That leanness means the device could fit frames no bigger than ordinary eyeglasses and rest on the bridge of the nose for hours without neck fatigue.<\/p>\n Choi calls the experience mixed reality rather than virtual<\/a> because real scenery seeps through untreated areas of the lenses. <\/p>\n A digitally summoned sculpture can sit on your real coffee table while sunlight streams around its edges.<\/p>\n How light moves in holographic glasses<\/p>\n Conventional surface relief gratings leak light in both directions, washing images with glare. <\/p>\n The Stanford design swaps those gratings for angle encoded volume Bragg gratings<\/a> that diffract only one way and only within a narrow color band, thus cutting unwanted brightness to the eye.<\/p>\n Three sets of gratings funnel red, green, and blue laser light through identical paths, minimizing chromatic blur. <\/p>\n After two reflections, the beam lands on the modulator and the modulated wave then passes through a holographic eyepiece that puts the picture at optical infinity.<\/p>\n The waveguide approach also eliminates large, curved lenses, so there is no need for the physical depth normally required to bring a screen into focus. Flattening the optics is what allows the package to be as thin as a credit card.<\/p>\n Wide natural view<\/p>\n Optical designers crave a high \u00e9tendue<\/a>, the product of field of view and eyebox size. A large number means the user can move pupils freely while still seeing a wide scene, a combination that is usually impossible in thin devices.<\/p>\n The prototype delivers a 38 degree diagonal field and a 0.35 by 0.31 inch (8.8 by 7.9 millimeter) eyebox. These values are two orders of magnitude higher than earlier holographic glasses. <\/p>\n Users can glance around the virtual scene without losing sharpness, a property that makes the imagery feel fixed in space rather than painted on the retina.<\/p>\n \u00c9tendue grows here because a scanning laser creates a synthetic aperture. Ten by ten overlapping sub pupils are stitched together by software. Each patch carries partial information<\/a>, yet the sum recreates a seamless light field.<\/p>\n AI sharpens holographic glasses visuals<\/p>\n To polish those patches, the team trained an implicit neural network that learns how partially coherent light meanders inside the glass. <\/p>\n The algorithm maps four dimensional spatio-angular coordinates to the complex wavefront that finally leaves the guide, which trims optical errors in real time.<\/p>\n Earlier models<\/a> relied on convolutional networks and assumed perfect coherence, an unrealistic simplification. <\/p>\n The new network needs roughly one-tenth of the training data yet predicts wave propagation more accurately across the entire synthetic aperture.<\/p>\n Artificial intelligence also handles phase retrieval, the math that converts a target scene into a pattern of voltages for the modulator. <\/p>\n By supervising on-light field rather than ray tracing errors, the system maintains image fidelity, even when eye position or pupil size changes.<\/p>\n Testing in the lab<\/p>\n Captured photos show a Snellen<\/a> equivalent resolution of 1.2 arcminutes, which is close to 20\/20 vision. Text remains legible as the camera focuses from infinity to 16 inches (40 centimeters), demonstrating that vergence and accommodation cues line up.<\/p>\n \u201cThis is the best 3D display created so far and a great step forward,\u201d Wetzstein remarked in the lab. His statement comes with caution. <\/p>\n Volume three of his \u201ctrilogy\u201d aims for a commercial product, a milestone he predicts is several years away.<\/p>\n Bench tests also reveal little vignetting while sliding a mock eye laterally across the entire 0.35 inch (8.9 millimeter) eyebox. <\/p>\n Vertical motion tolerance is almost as forgiving, which will be a relief for users whose headsets inevitably slip during normal movement.<\/p>\n Holographic glasses, VR, and the future<\/p>\n Education, remote collaboration, and telemedicine could be early winners because lightweight glasses lower the barrier to all day wear. <\/p>\n Architects might sketch holographic beams into a construction site, and surgeons could overlay imaging data directly on a patient without glancing at monitors.<\/p>\n Challenges remain. Higher frame rates demand faster modulators, and the laser driven backlight must pass regulatory safety checks. <\/p>\n Mass manufacturing of volume Bragg gratings with nanometer precision is still expensive.<\/p>\n Even so, shrinking a mixed reality display to the scale of everyday eyewear edges digital content toward physical parity. Passing a visual exam once reserved for humans no longer feels far fetched.<\/p>\n The study is published in Nature Photonics<\/a>.<\/p>\n \u2014\u2013<\/p>\n Like what you read? Subscribe to our newsletter<\/a> for engaging articles, exclusive content, and the latest updates.\u00a0<\/p>\n Check us out on EarthSnap<\/a>, a free app brought to you by Eric Ralls<\/a> and Earth.com.<\/p>\n \u2014\u2013<\/p>\n","protected":false},"excerpt":{"rendered":"Virtual reality keeps improving, yet most headsets still clamp a heavy box to your face and flatten scenes…\n","protected":false},"author":2,"featured_media":325666,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3162],"tags":[53,16,15,3243,3244],"class_list":{"0":"post-325665","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-virtual-reality","8":"tag-technology","9":"tag-uk","10":"tag-united-kingdom","11":"tag-virtual-reality","12":"tag-vr"},"share_on_mastodon":{"url":"https:\/\/pubeurope.com\/@uk\/114988505137365172","error":""},"_links":{"self":[{"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/posts\/325665","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/comments?post=325665"}],"version-history":[{"count":0,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/posts\/325665\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/media\/325666"}],"wp:attachment":[{"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/media?parent=325665"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/categories?post=325665"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/tags?post=325665"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}![\"An](\"https:\/\/www.europesays.com\/uk\/wp-content\/uploads\/2025\/08\/holographic-virtual-reality-glasses_MR-display-system_graphic_credit-Nathan-Matsuda_1s.webp.webp\")
<\/a>An illustration of the synthetic aperture waveguide holography principle. The illumination module consists of a collimated fibre-coupled laser, a MEMS mirror that steers the input light angle, and a holographic waveguide. Together, these components serve as a partially coherent backlight of the SLM. The SLM is synchronized with the MEMS mirror and creates a holographic light field, which is focused towards the user\u2019s eye using an eyepiece lens. Click image to enlarge. Credit: Stanford University<\/p>\n