How to construct liquid-crystal spectacles to control vision of real-world objects and environments

Abstract

A major challenge in studying naturalistic vision lies in controlling stimulus and scene viewing time. This is especially the case for studies using real-world objects as stimuli (rather than computerized images) because real objects cannot be “onset” and “offset” in the same way that images can be. Since the late 1980s, one solution to this problem has been to have the observer wear electro-optic spectacles with computer-controlled liquid-crystal lenses that switch between transparent (“open”) and translucent (“closed”) states. Unfortunately, the commercially available glasses (PLATO Visual Occlusion Spectacles) command a high price tag, the hardware is fragile, and the glasses cannot be customized. This led us to explore how to manufacture liquid-crystal occlusion glasses in our own laboratory. Here, we share the products of our work by providing step-by-step instructions for researchers to design, build, operate, and test liquid-crystal glasses for use in experimental contexts. The glasses can be assembled with minimal technical knowledge using readily available components, and they can be customized for different populations and applications. The glasses are robust, and they can be produced at a fraction of the cost of commercial alternatives. Tests of reliability and temporal accuracy show that the performance of our laboratory prototype was comparable to that of the PLATO glasses. We discuss the results of our work with respect to implications for promoting rigor and reproducibility, potential use cases, comparisons with other liquid-crystal shutter glasses, and how users can find information regarding future updates and developments.

Optimizing Tunable LC Devices with Twisted Light

“…Crystals 2024, 14, 16 6 of 31 the structure. Removing material may produce a dramatic decrease in the device thickness, making it possible for regular LC samples in the 10′s µm range to develop lens powers of several diopters.…”

“…Crystals 2024, 14, 16 26 of 31 previous case, but the power of the resulting lens is twice the power of the individual lenses.…”

“…At present, LC lenses are finding applications in many dissimilar fields, such as vision (e.g., eyeglasses [16], contact lenses [17], and intraocular lenses [18]), adaptive optics for astronomy [19], or wearable devices [20], in addition to their traditional applications as tunable lenses for consumer photonics [21,22].…”

“…Crystals 2024, 14,16 23 of 31point is to realize that the external connections keep electric continuity from the edge to the center; no further wiring is necessary.…”