Introduction
The rapid rise in screen time in both children and adults has coincided with a marked global increase in myopia (nearsightedness). While genetic and environmental factors both contribute to myopia, a growing body of research points to near-work activities (like close distance or extended screen use) as critical risk factors. One of the key culprits? Retinal defocus, especially in the peripheral retina, induced by the flat, fixed-depth nature of conventional displays [1–3].
At Brelyon, we’re not just building immersive display systems — we’re reimagining visual ergonomics. This article explores how one’s visual environment shapes eye growth, and how depth-based immersive displays may support healthier visual behavior by altering key factors like accommodation and peripheral defocus.
The Problem with Near Work and Conventional Displays
Myopic defocus occurs when light rays converge and focus in front of the retina, while hyperopic defocus refers to light focusing behind the retinal surface, often in the peripheral regions (see Fig. 1). During near tasks — such as reading, using a computer, or viewing a smartphone — our eyes must converge and accommodate to maintain focus on close objects. Prolonged engagement in such activities places significant strain on the visual system. Although central accommodation may remain accurate, it does not fully correct for peripheral blur. This mismatch often results in peripheral hyperopic defocus, a condition illustrated in Fig. 1, where the peripheral image is focused behind the retina [4].
Press enter or click to view image in full size
Numerous studies show that this type of defocus acts as a biological signal for axial elongation of the eyeball, the hallmark of progressive myopia [1–7]. In essence, when peripheral blur is interpreted as hyperopic, the eye “responds” by growing longer to bring the image into focus — ironically pushing central vision into myopic territory. The visual environment indoors compounds this problem: objects are close and unevenly distributed in depth, causing a complex “dioptric landscape” (the scene as the eye perceives it) across the retina [1]. In contrast, outdoor environments present much more uniform optical fields, allowing the eye to maintain consistent focus and reducing stimuli for axial elongation [8].
This is shown in Fig. 2 in which the comparison of different visual tasks and fixation distances reveals that indoor environments — due to their compact, three-dimensional structure — produce complex patterns of retinal defocus, especially in the peripheral retina [1]. Fig. 2 visually reinforces the concept that the eye’s growth is regulated by the pattern of defocus across the retina, with peripheral hyperopic defocus promoting elongation and myopic defocus providing a “stop” signal [1]. When the peripheral retina experiences hyperopic defocus (as occurs with near work or small-screen use), there is a stimulus for axial elongation, leading to myopia progression. This demonstrates that this elongation is not uniform but is driven by localized optical signals, particularly in the peripheral retina, which can override central (foveal) focus cues. Conversely, when the peripheral retina is exposed to myopic defocus, axial elongation is inhibited or slowed, supporting the use of optical interventions (such as multifocal lenses) that induce peripheral myopic defocus to control myopia progression [7].
Press enter or click to view image in full size
Accommodation Lag and Hyperopic Defocus
Accommodation lag — a slight delay or insufficiency in the eye’s focusing ability — means that even central vision during near work can be hyperopically defocused, especially in myopic individuals [9–11]. This creates central retinal blur, further reinforcing the biological triggers for eye growth. The most vulnerable populations are children and adolescents, whose eyes are still in the critical stages of emmetropization [12, 13]. Animal studies and human cohort data suggest that just a few hours of hyperopic defocus per day can accelerate axial growth, especially in younger eyes [5, 14].
The Depth Challenge in AR/VR and 3D Displays
AR and VR systems add another dimension to the problem. While traditional flat screens require constant near accommodation, ARVR tech struggles with the accommodation-vergence conflict. In real-world vision, vergence (eye turning) and accommodation (focusing) are coordinated and reinforce each other. But in most VR and AR systems, the eyes converge on virtual depth planes while the focal demand remains at the fixed distance of the headset’s optics (see Fig. 3). This accommodation-vergence mismatch is unnatural and leads to visual fatigue, blur, and — potentially — long-term refractive consequences if used extensively [15–17]. Such systems can worsen symptoms of digital eye strain and do not adequately stimulate the natural range of depth focus needed for healthy visual development. Moreover, conventional VR displays still present significant peripheral hyperopic defocus, which can continue to promote eye elongation, particularly in growing eyes [14, 18].
Press enter or click to view image in full size
The Discomfort of Hyperopic Defocus
Beyond long-term eye growth, hyperopic defocus is perceptually unpleasant. It’s associated with symptoms like:
- Blurry peripheral vision
- Eye strain and fatigue
- Headaches, particularly with prolonged close work
This discomfort is especially prominent in digital environments where visual ergonomics are suboptimal. Even among adults, sustained focus at short distances has been linked with digital eye strain, sometimes called computer vision syndrome [14, 18].
How Brelyon’s Technology Alters the Visual Equation
Brelyon’s light-field display systems provide a radically different approach. By simulating a panoramic virtual screen with real depth cues at farther depths, Brelyon displays reduce the demand for extreme convergence and encourage naturalistic depth perception [19]. In essence, our displays push your depth cues farther away, making near work feel less near (see Fig. 4). This allows users to engage in visually intensive tasks without the typical strain associated with close-up screens. Our displays can present different depth planes more realistically — without headsets — way.
This matters for several reasons:
- Reduced Near Lag of Accommodation: Because virtual images can appear at mid or far distances, the eyes can relax more, reducing the lag that drives central hyperopic defocus.
- Peripheral Focus Consistency: Our light-field technology minimizes abrupt gradients in peripheral defocus by offering a virtual image closer to the natural horopter than what is seen in traditional near displays (see the right panel in Fig. 3).
- Decreased Visual Fatigue: The lack of accommodation-vergence conflict — common in headset-based systems — leads to more comfortable and sustainable viewing sessions, potentially helping maintain or even enhance acuity reserve, i.e., the ability of the eye to see fine details.[20].
Together, these changes might help reduce some of the optical conditions that promote myopia progression, particularly in professional or prolonged use settings.
Fig. 5 illustrates the ranking of display technologies by accommodation-vergence mismatch and accommodation error — from projector to AR — that reflects the degree to which each system disrupts the natural coupling between where the eyes converge (vergence) and where they focus (accommodation). Projectors and TVs, positioned several meters away, offer fixed and consistent vergence and accommodation cues, closely matching real-world viewing and minimizing visual fatigue. Brelyon displays, although closer than projectors or TVs, simulate distant focal points through light field manipulation, preserving a more natural depth experience. Monitors, tablets, and cell phones progressively reduce the viewing distance while still providing a fixed accommodation point, increasing the likelihood of vergence-accommodation conflict. IMAX 3D introduces artificial depth via binocular disparity while the screen remains several meters away, keeping the accommodation cue fixed, yet inducing moderate conflict. In autostereoscopic displays (e.g., glasses-free 3D), viewers sit closer to the screen, but the displayed 3D images may appear to be much farther away, increasing mismatch due to conflicting vergence and accommodation cues. VR and AR headsets bring the physical screen extremely close to the eyes, but simulate a wide range of depths. This results in a range of vergence-accommodation mismatches, since the eyes must converge on virtual depths while continuing to accommodate at the near physical screen, leading to the highest levels of mismatch and visual discomfort (see Fig. 3).
Press enter or click to view image in full size
Scientific Consensus and Practical Advice
Numerous longitudinal and cross-sectional studies support interventions such as:
- Increasing outdoor time (2+ hours/day) [8]
- Limiting continuous near work sessions [10, 11]
- Maintaining working distances of at least 40 cm [4, 9]
- Using display systems that reduce the need for accommodation or encourage far-distance viewing [21]
Brelyon’s display systems align with these principles not by making sustained visual tasks more compatible with them. Our immersive screens allow for expansive, natural viewing fields — supporting a less stressful visual environment.
Conclusion
The rise of myopia is a modern public health issue, driven in large part by our visual behaviors and environments. Although technology plays a major role in driving this epidemic, it also offers a potential path forward.
By integrating depth-aware optical systems, minimizing accommodation-vergence conflict, and reducing peripheral hyperopic defocus, display technologies like those developed at Brelyon might support healthier visual habits and reduce long-term myopia risk — especially in settings where screen use is unavoidable.
We believe the future of immersive display isn’t just about better visuals — it’s also about better visual health.
References
[1] Flitcroft, D. I. “The complex interactions of retinal, optical and environmental factors in myopia aetiology.” Progress in retinal and eye research 31, no. 6 (2012): 622–660.
[2] Flitcroft, Daniel Ian, Mingguang He, Jost B. Jonas, Monica Jong, Kovin Naidoo, Kyoko Ohno-Matsui, Jugnoo Rahi, Serge Resnikoff, Susan Vitale, and Lawrence Yannuzzi. “IMI–defining and classifying myopia: a proposed set of standards for clinical and epidemiologic studies.” Investigative ophthalmology & visual science 60, no. 3 (2019): M20-M30.
[3] Ip, Jenny M., Seang-Mei Saw, Kathryn A. Rose, Ian G. Morgan, Annette Kifley, Jie Jin Wang, and Paul Mitchell. “Role of near work in myopia: findings in a sample of Australian school children.” Investigative ophthalmology & visual science 49, no. 7 (2008): 2903–2910.
[4] Mutti, Donald O., John R. Hayes, G. Lynn Mitchell, Lisa A. Jones, Melvin L. Moeschberger, Susan A. Cotter, Robert N. Kleinstein, Ruth E. Manny, J. Daniel Twelker, and Karla Zadnik. “Refractive error, axial length, and relative peripheral refractive error before and after the onset of myopia.” Investigative ophthalmology & visual science 48, no. 6 (2007): 2510–2519.
[5] Delshad, Samaneh, Michael J. Collins, Scott A. Read, and Stephen J. Vincent. “The time course of the onset and recovery of axial length changes in response to imposed defocus.” Scientific reports 10, no. 1 (2020): 8322.
[6] Kim, Hong Kyu, and Sung Soo Kim. “Factors associated with axial length elongation in high myopia in adults.” International journal of ophthalmology 14, no. 8 (2021): 1231.
[7] Lin, Weiping, Na Li, Kunpeng Lu, Zhaochun Li, Xiaohua Zhuo, and Ruihua Wei. “The relationship between baseline axial length and axial elongation in myopic children undergoing orthokeratology.” Ophthalmic and Physiological Optics 43, no. 1 (2023): 122–131.
[8] Zhang, Jun, and Guohua Deng. “Protective effects of increased outdoor time against myopia: a review.” Journal of International Medical Research 48, no. 3 (2020): 0300060519893866.
[9] Li, Shi-Ming, Si-Yuan Li, Meng-Tian Kang, Yuehua Zhou, Luo-Ru Liu, He Li, Yi-Peng Wang et al. “Near work related parameters and myopia in Chinese children: the Anyang Childhood Eye Study.” PloS one 10, no. 8 (2015): e0134514.
[10] Czepita, Maciej, Leszek Kuprjanowicz, Krzysztof Safranow, Artur Mojsa, Ewa Majdanik, Maria Ustianowska, and Damian Czepita. “The role of reading, writing, using a computer, or watching television in the development of myopia.” Ophthalmology Journal 1, no. 2 (2016): 53–57.
[11] Wen, Longbo, Yingpin Cao, Qian Cheng, Xiaoning Li, Lun Pan, Lei Li, HaoGang Zhu, Weizhong Lan, and Zhikuan Yang. “Objectively measured near work, outdoor exposure and myopia in children.” British Journal of Ophthalmology 104, no. 11 (2020): 1542–1547.
[12] Huang, Hsiu-Mei, Dolly Shuo-Teh Chang, and Pei-Chang Wu. “The association between near work activities and myopia in children — a systematic review and meta-analysis.” PloS one 10, no. 10 (2015): e0140419.
[13] Guo, Lan, J. Yang, J. Mai, X. Du, Y. Guo, P. Li, Y. Yue, D. Tang, C. Lu, and Wei Hong Zhang. “Prevalence and associated factors of myopia among primary and middle school-aged students: a school-based study in Guangzhou.” Eye 30, no. 6 (2016): 796–804.
[14] Sheppard, Amy L., and James S. Wolffsohn. “Digital eye strain: prevalence, measurement and amelioration.” BMJ open ophthalmology 3, no. 1 (2018).
[15] Dutheil, Frédéric, Tharwa Oueslati, Louis Delamarre, Joris Castanon, Caroline Maurin, Frédéric Chiambaretta, Julien S. Baker et al. “Myopia and near work: a systematic review and meta-analysis.” International journal of environmental research and public health 20, no. 1 (2023): 875.
[16] Erkelens, Ian M., and Kevin J. MacKenzie. “19‐2: Vergence‐Accommodation conflicts in augmented reality: Impacts on perceived image quality.” In SID Symposium Digest of Technical Papers, vol. 51, no. 1, pp. 265–268. 2020.
[17] Yoon, Hyeon Jeong, Jonghwa Kim, Sang Woo Park, and Hwan Heo. “Influence of virtual reality on visual parameters: immersive versus non-immersive mode.” BMC ophthalmology 20 (2020): 1–8.
[18] Long, Jennifer, Rene Cheung, Simon Duong, Rosemary Paynter, and Lisa Asper. “Viewing distance and eyestrain symptoms with prolonged viewing of smartphones.” Clinical and Experimental Optometry 100, no. 2 (2017): 133–137.
[19] Aghasi, Alireza, Barmak Heshmat, Leihao Wei, and Moqian Tian. “Optimal allocation of quantized human eye depth perception for multi-focal 3D display design.” Optics Express 29, no. 7 (2021): 9878–9896.
[20] Foreman, Joshua, Arief Tjitra Salim, Anitha Praveen, Dwight Fonseka, Daniel Shu Wei Ting, Ming Guang He, Rupert RA Bourne, Jonathan Crowston, Tien Y. Wong, and Mohamed Dirani. “Association between digital smart device use and myopia: a systematic review and meta-analysis.” The Lancet Digital Health 3, no. 12 (2021): e806-e818.
[21] Pärssinen, Olavi, and Markku Kauppinen. “Risk factors for high myopia: a 22‐year follow‐up study from childhood to adulthood.” Acta ophthalmologica 97, no. 5 (2019): 510–518.