Accommodation-Free Head Mounted Display with Comfortable 3D Perception and an Enlarged Eye-box

Abstract

<jats:p>An accommodation-free displays, also known as Maxwellian displays, keep the displayed image sharp regardless of the viewer’s focal distance. However, they typically suffer from a small eye-box and limited effective field of view (FOV) which requires careful alignment before a viewer can see the image. This paper presents a high-quality accommodation-free head mounted display (aHMD) based on pixel beam scanning for direct image forming on retina. It has an enlarged eye-box and FOV for easy viewing by replicating the viewing points with an array of beam splitters. A prototype aHMD is built using this concept, which shows high definition, low colour aberration 3D augmented reality (AR) images with an FOV of 36°. The advantage of the proposed design over other head mounted display (HMD) architectures is that, due to the narrow, collimated pixel beams, the high image quality is unaffected by changes in eye accommodation, and the approach to enlarge the eye-box is scalable. Most importantly, such an aHMD can deliver realistic three-dimensional (3D) viewing perception with no vergence-accommodation conflict (VAC). It is found that viewing the accommodation-free 3D images with the aHMD presented in this work is comfortable for viewers and does not cause the nausea or eyestrain side effects commonly associated with conventional stereoscopic 3D or HMD displays, even for all day use.</jats:p>

Augmented reality and virtual reality displays: emerging technologies and future perspectives

“…Methods to expand eyebox can be generally categorized into pupil duplication [168][169][170][171][172] and pupil steering 9,13,167,173 . Pupil duplication simply generates multiple viewpoints to cover a large area.…”

“…10d), which equals to shifting the light source position. Other like a grating or beam splitter can also serve as ray deflector/splitter 170,171 (Fig. 10e).…”

Gaze‐Matched Pupil Steering Maxwellian‐View Augmented Reality Display with Large Angle Diffractive Liquid Crystal Lenses

“…To enlarge the eyebox of a Maxwellian-view display, two major approaches have been developed: pupil duplication (Figure 1a) [18] and pupil steering (Figure 1b). [5,12,19,20] As Figure 1a depicts, pupil duplication methods usually utilize a HOE, [18,21] beam splitter array, [22] or spatial light modulator (SLM) [23] to split the collimated beam into multiple directions, so that each direction corresponds to one viewing point. This approach is cost-effective because no additional eye-tracking system is needed, but it will introduce some problems.…”

“…As Figure 1a depicts, pupil duplication methods usually utilize a HOE, [ 18,21 ] beam splitter array, [ 22 ] or spatial light modulator (SLM) [ 23 ] to split the collimated beam into multiple directions, so that each direction corresponds to one viewing point. This approach is cost‐effective because no additional eye‐tracking system is needed, but it will introduce some problems.…”

Pupil steerable Maxwellian AR display with gaze matching

“…4,5 However, the most significant drawback of Maxwellian system is its small eyebox. Several approaches have been proposed to enlarge the eyebox, and they can be classified into two groups: pupil duplication (Figure 1A) [6][7][8] and pupil steering (Figure 1B). [9][10][11][12] In Figure 1A, pupil duplication aims to split the collimated beam into multiple directions by using a HOE, 6,13 beam splitter array, 7 or spatial light modulator (SLM), 8 and each direction corresponds to one viewpoint.…”