Holographic Technology & Vision Simulator

Holographic Technology & Vision Simulator

July 18, 2021

The only technology that can provide genuine 3D with the necessary depth clues is holographic display. For a comfortable 3D experience, holographic head-worn displays (HWD) can deliver continuous depth planes with the appropriate stereoscopic disparity. The spatial light modulator restricts the tiny FOV and small exit pupil size of existing HWD methods (SLM).

Using a 4 K SLM panel, conventional holographic HWDs are restricted to a fixed FOV of around 20° 11°. Patients with cataracts will be able to enjoy the best-corrected eyesight possible before surgery thanks to a holographic vision simulator system created specifically for them.

Although there are technologies for diagnosing cataracts, such as retinoscopy, aberrometry, optical coherence tomography, and biometry, their preoperative performance cannot predict the postoperative visual acuity, they cannot correct aberrations, and they are restricted to static pinhole exit pupils.

Holography is considered the ultimate display technology that can offer natural 3-dimensional vision with all required focus and depth cues,” said Koray Kavakli, MS, a student, and Hakan Urey, PhD, a professor of electrical engineering, both from the Department of Electrical Engineering and the Translational Medicine Research Center at Koc University in Istanbul, Turkey.

The phase, size, and shape of a light beam entering the pupil can only be digitally controlled through holography, according to Kavakli. Prior to using the simulator in this study, the 10 patients with various degrees of cataracts had their eyes examined. Throughout the tests, they had the holographic vision simulator on their heads. The holographic screens use pupil tracking to steer a light beam that shapes the output pupil in order to detect solid noncataractous spots on the crystalline lens with millimeter-level accuracy.

The simulated vision the patients achieve, said Kavakli, facilitates their choice of different IOL options offered preoperatively and correction of any refractive errors. Results “All patients had better visual acuity when tested in our holographic simulator compared to the conventional eye examination,” Kavakli said. “Patients without retina diseases exhibited 20/40 vision, whereas the patients with age-related macular degeneration or glaucoma had 20/70 vision.” Based on the results, the investigators concluded that the vision simulator can predict the patients’ postoperative visual acuity before they undergo cataract surgery.

“Our augmented-reality display device overperforms the existing vision simulators,” they commented. “This device also can be used for matching the right patient to the right choice of intraocular lenses, such as trifocal, monofocal, or extended depth-of-focus IOLs.”

The researchers also pointed out that the technique can be used to corneal conditions like keratoconus that call for surgery and cannot be treated with contact lenses.