<div>
	Aberration analysis of a wedge as a compensator element in augmented and virtual reality systems.</div>

Romanova Galina Eduardovna, Ngoc Son Nguyen

2021 , VOLUME 21, NUMBER 6 ( november-december )

ISSN 2226-1494 (print), ISSN 2500-0373 (online)

Publications

Editor-in-Chief

Nikiforov
Vladimir O.
D.Sc., Prof.

Partners

doi: 10.17586/2226-1494-2021-21-6-808-816

Aberration analysis of a wedge as a compensator element in augmented and virtual reality systems.

G. E. Romanova, N. S. Nguyen

Read the full article

Article in Russian

For citation:

Romanova G.E., Nguyen N.S. Aberration analysis of a wedge as a compensator element in augmented and virtual reality systems. Scientific and Technical Journal of Information Technologies, Mechanics and Optics, 2021, vol. 21, no. 6, pp. 808–816 (in Russian). doi: 10.17586/2226-1494-2021-21-6-808-816

Abstract

The paper considers the optical systems of virtual reality, which use an optical wedge to eliminate or reduce the conflict of convergence and accommodation (vergence-accommodation conflict, VAC). The inclined surfaces of the optical wedge introduce specific aberrations into the optical system that can critically affect image quality. The authors analyzed wedge aberrations using relationships derived from the third-order aberration theory. In contrast to existing approaches, the relationships were obtained without the assumption of a small refractive angle or wedge thickness. The results demonstrate that in the scheme with an optical wedge, with characteristics typical for virtual reality systems, the dependence of astigmatism on the angular field is linear and significantly exceeds the other types of aberrations. It is shown that to obtain a high-quality image, the most successful compensation for such aberration can be achieved by using diffractive optical elements (kinoforms) or a Fresnel lens. The paper gives examples of optical systems with a wedge, developed taking into account the requirements for the overall dimensions of virtual reality systems and image quality. The obtained ratios for the aberrations of the optical wedge and the inclined surface make it possible to evaluate the correction capabilities of schemes where such elements are used with arbitrary characteristics. The proposed solutions can be used in virtual reality systems with a reduced value of vergence-accommodation conflict.

Keywords: optical wedge, vergence-accomodation conflict, aberration analysis, virtual reality, augmented reality

Acknowledgements. Nguyen Ngoc Son acknowledges support from the Vietnam Scholarship Council.

References

Hoffman D.M., Girshick A.R., Akeley K., Banks M.S. Vergence–accommodation conflicts hinder visual performance and cause visual fatigue. Journal of Vision, 2008, vol. 8, no. 3, pp. 33. https://doi.org/10.1167/8.3.33
Shibata T., Kim J., Hoffman D.M., Banks M.S. The zone of comfort: Predicting visual discomfort with stereo displays. Journal of Vision, 2011, vol. 11, no. 8, pp. 11. https://doi.org/10.1167/11.8.11
Bankset M.S., Kim J., Shibata T. Insight into vergence-accommodation mismatch. Proceedings of SPIE, 2013, vol. 8735, pp. 873509. https://doi.org/10.1117/12.2019866
Akşit K., Lopes W., Kim J., Shirley P., Luebke D. Near-eye varifocal augmented reality display using see-through screens. ACM Transactions on Graphics, 2017, vol. 36, no. 6, pp. 1. https://doi.org/10.1145/3130800.3130892
Hasnain A., Laffont P.-Y., Jalil S.B.A., Buyukburc K., Guillemet P.-Y., Wirajaya S., Khoo L., Teng D., Bazin J.C. Piezo-actuated varifocal head-mounted displays for virtual and augmented reality. Proceedings of SPIE, 2019, vol. 10942, pp. 1094207. https://doi.org/10.1117/12.2509143
Liu S., Cheng D., Hua H. An optical see-through head mounted display with addressable focal planes. Proc. of the 7^th IEEE/ACM International Symposium on Mixed and Augmented Reality, 2008, pp. 33–42. https://doi.org/10.1109/ISMAR.2008.4637321
Akeley K., Watt S.J., Girshick A.R., Banks M.S. A stereo display prototype with multiple focal distances. ACM Transactions on Graphics, 2004, vol. 23, no. 3, pp. 804. https://doi.org/10.1145/1015706.1015804
Rolland J.P., Krueger M.W., Goon A. Multifocal planes head-mounted displays. Applied Optics, 2000, vol. 39, no. 19, pp. 3209–3215. https://doi.org/10.1364/AO.39.003209
Cheng D., Wang Q., Wang Y., Jin G. Lightweight spatial-multiplexed dual focal-plane head-mounted display using two freeform prisms. Chinese Optics Letters, 2013, vol. 11, no. 3, pp. 031201 https://doi.org/10.3788/COL201311.031201
Song W., Wang Y., Cheng D., Liu Y. Light field head-mounted display with correct focus cue using microstructure array. Chinese Optics Letters, 2014, vol. 12, no. 6, pp. 060010. https://doi.org/10.3788/COL201412.060010
Song W., Wang Y., Cheng D., Liu Y. Design of light field head-mounted display. Proceedings of SPIE, 2014, vol. 9293, pp. 92930J. https://doi.org/10.1117/12.2075183
Sluka T. Near-eye sequential light-field projector with correct monocular depth cues. Patent WO2018091984A1, 2017.
Wilson A., Hua H. High-resolution optical see-through vari-focal-plane head-mounted display using freeform Alvarez lenses. Proceedings of SPIE, 2018, vol. 10676, pp. 106761J. https://doi.org/10.1117/12.2315771
Cui W., Gao L. Optical mapping near-eye three-dimensional display with correct focus cues. Optics Letters, 2017, vol. 42, no. 13, pp. 2475–2478. https://doi.org/10.1364/OL.42.002475
Ngoc Son Nguyen, Romanova G.E. Overcoming the conflict of convergence and accommodation in virtual and augmented reality systems. Journal of Instrument Engineering, 2021, vol. 64, no. 2, pp. 143–152. (in Russian). https://doi.org/10.17586/0021-3454-2021-64-2-143-152
Riedl M.J. Optical Design Fundamentals for Infrared Systems. SPIE Press, 2001, pp. 90.
Utekhin Iu.A. Optical methods and tools for restoring binocular vision. Dissertation abstract for the degree of doctor of technical sciences. St. Petersburg, Saint Petersburg Institute of Fine Mechanics and Optics, 1993, 49 p. (in Russian)
Sasián J.M. Aberrations from a prism and a grating. Applied Optics, 2000, vol. 39, no. 1, pp. 34–39. https://doi.org/10.1364/AO.39.000034
Howard J.W. Formulas for the coma and astigmatism of wedge prisms used in converging light. Applied Optics, 1985, vol. 24, no. 23, pp. 4265–4268. https://doi.org/10.1364/AO.24.004265
Barth C.J., Oepts D. Stigmatic and coma-free imaging with a thick prism: a comparison of third-order theory and ray-tracing results. Applied Optics, 1988, vol. 27, no. 18, pp. 3838–3844. https://doi.org/10.1364/AO.27.003838
Kidger M. Fundamental Optical Design. SPIE Press, 2002, pp. 107.
Geary J.M. Introduction to Lens Design: With Practical ZEMAX Examples. Willmann-Bell, 2002, pp. 110.
Delano E. Primary aberrations of Fresnel lenses. Journal of the Optical Society of America, 1974, vol. 64, no. 4, pp. 459–468. https://doi.org/10.1364/JOSA.64.000459
Bobrov S.T., Greisukh G.I., Turkevich Iu.G. Optics of diffractive elements and systems. Leningrad, Mashinostroenie Publ., 1986, 23 p. (in Russian)
Zemax Optic Studio 19.8 User manual. October 2019.

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License