Termination of Eyestrain and Myopia

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Introduction

In humans, prolonged contraction of the ciliary and medial rectus muscles during close reading will result in eye strain.

On the other hand, eye strain will not occur if the ciliary and medial rectus muscles do not contract during close reading.

The near-eye display (NED)[1] technology of Augmented reality smart glasses (AR glasses) projects computer generated images(CGI) directly onto the retina, and this provides a new way for our eyes to acquire information.

Figure 1. Projection of CGI onto the retina

Factors contributing to eyestrain and myopia

In the medical community, the main factors considered to causing eye fatigue and myopia are as follows:

1. Long-term contraction of the ciliary muscle.

2. Long-term contraction of the medial rectus muscle.

3. Insufficient exposure of the retina to sunlight.[2]

4. The eye not exhibiting peripheral myopia.[3]

5. Peripheral visual field deprivation.[4]

Disease prevention

With the NED technology, augmented reality smart glasses have the potential to play an important role in the prevention of asthenopia and myopia.

Prevention of asthenopia

Similar in principle to an ophthalmoscope shining light into the eye, the NED [1] optical engine of AR glasses actively projects computer-generated images(CGI) onto the retina.

①. Once any refractive errors are corrected, people of any age can receive the CGI clearly via the retina; this indicates that the light projected from the NED is indeed parallel light.

②. Once the refractive error is corrected, the CGI emitted by the parallel light is naturally focused on the retina without any accommodation.  

③. By extension of the accommodation-vergence reflex, no accommodation, no convergence.

Therefore, there is no contraction of the ciliary and medial rectus muscle.

So by using augmented reality glasses, humans can read at close range with both the ciliary and medial rectus muscles relaxed, and the eyes will never get tired.

In short, the projection of CGI onto the retina by the NED technology is purely a physical phenomenon of light and has nothing to do with physiological action.

Prevention of myopia

AR glasses can be turned into AR computer by appending a piece of opaque material on the front of the screen to turn the see-through display into a non see-through one and installing a personal computer operating system on its host.

Figure 2. An augmented reality personal computer (AR Computer)


Figure 3. Attaching an opaque material on the front of the screen


• The AR Computer is equipped with a light-transmittable part around the opaque display. The opaque display allows the user to face the sun and use sunlight as the background light source. The opaque display protects the eyeball and the macula, while the light-transmittable part allows the peripheral retina to come into contact with sunlight.

• The AR Computer can be equipped with convex lenses around the opaque display. The convex lens can shorten the focal length of the light around the opaque display (i.e. the macula area) and change the light that is originally focused on the outside of the retina to the inside, turning the relative peripheral hyperopia into peripheral myopia.

Figure 4. AR Computer without convex lens
Figure 5. AR Computer with convex lens


• With the head raised, the light-transmittable part of AR Computer provides a wide field of view, eliminating the phenomenon where the peripheral visual field is deprived when reading with the head down.

Figure 6. No peripheral visual field deprivation


Thus, the AR computer can simultaneously overcome all the major factors contributing to myopia.

Further advantages

AR Computer can perform all the work of a traditional computer, besides, it has the unique ability of AR glasses.

No reading glasses required

As long as the refractive error is corrected, people of any age can get a clear picture, so the elderly do not need reading glasses when using AR Computer.

Relieve eye fatigue

Once the refractive error is corrected, both the ciliary and medial rectus muscles are relaxed. Therefore, the use of AR computer may relieve eye fatigue caused by prolonged contraction of the ciliary and medial rectus muscles due to long-term close reading.

Unaffected by vehicle vibration

The display of AR Computer moves synchronously with the user’s eyes, and the images remain clear and relatively stable even on moving vehicles.

No dizziness

As both the ciliary and medial rectus muscles are relaxed, there is no vergence-accommodation conflict (VAC), so there is no dizziness.

Large virtual screen

The size of the perceived image in the brain depends on the distance between the viewer and the target screen. For example, at a 34° angle of view, the image is 120 inches at a distance of 5 meters, and 240 inches at 10 meters.

2.5D and 3D

Instead of a single screen, binocular AR computer provides dual-display. Each eye has its own image, rather than two eyes sharing the same one, which creates differences.

When two images are different, an IMAX-like 3D effect can be created, which can be used to view in many things—including any surgical operation in a Side-By-Side (SBS) 3D format.

On the other hand, when two images are identical, a visual effect somewhere between 2D and 3D can be generated, which hereafter is referred to as 2.5D. This offers a new way to see the 2D digital world and allows viewers to immerse themselves in the scene.

Hologram

A hologram is an interactive 3D digital image that may be moved, disassembled, assembled and changed through gestures.  It provides a playful way to observe, think, manipulate and explore in three dimensions.

In the medical field, it may be used for anatomical or surgical exercises and so on.

Supine position

The ability to use AR Computer while lying down means the muscles of the whole body are relaxed, the spine can be extended, and the vertebrae will no longer overlap and compress each other. So there will be no backaches or neck stiffness.

Dynamic reading over of static reading

The display moves with the line of sight, so the user can move their head and neck at will instead of having to look down. The light-transmitting part allows the user to see the surrounding environment even while using the AR Computer. So it encourages dynamic reading over static reading to avoid the complications of a sedentary lifestyle. In the confines of a safe environment, the user can even walk around.

Environmentally friendly

When AR Computer users go outdoors or face the outside, the use of artificial light is reduced, saving energy and being environmentally friendly.

Conclusion

Mankind has paid a heavy price for the acquisition of knowledge. Eye fatigue and myopia have plagued us for thousands of years.

AR Computer's potential in alleviating and preventing these afflicting conditions cannot be overstated.

Although its results still need to be supported by clinical trial data, the fact that it overcomes the currently known factors of myopia is promising.

The emergence of NED technology has revolutionized the mechanism for reading at close range, and is undoubtedly worthy of further exploration.

The end of myopia in humans may soon be at hand once clinical trials are carried out.

References

  1. 1.0 1.1 http://www.kessleroptics.com/portfolio/near-to-eye-displays
  2. Erica G. Landis, Victoria Yang, Dillon M. Brown, Machelle T. Pardue, Scott A. Read; Dim Light Exposure and Myopia in Children. Invest. Ophthalmol. Vis. Sci. 2018;59(12):4804-4811. doi: https://doi.org/10.1167/iovs.18-24415.
  3. Alexandra Benavente-Pérez, Ann Nour, David Troilo; Axial Eye Growth and Refractive Error Development Can Be Modified by Exposing the Peripheral Retina to Relative Myopic or Hyperopic Defocus. Invest. Ophthalmol. Vis. Sci. 2014;55(10):6765-6773. doi: https://doi.org/10.1167/iovs.14-14524.
  4. Smith EL 3rd, Hung LF, Arumugam B. Visual regulation of refractive development: insights from animal studies. Eye (Lond). 2014 Feb;28(2):180-8. doi: 10.1038/eye.2013.277. Epub 2013 Dec 13. PMID: 24336296; PMCID: PMC3930279.