Differences in the optical properties of photochromic lenses between cold and warm temperatures

Abstract

The aim of our study was to quantitatively evaluate the optical properties of photochromic lenses available on the market under cold and warm temperatures corresponding to the winter and summer seasons. The transmittance of 12 photochromic lenses from five manufacturers was measured using an UV/VIS spectrophotometer at cold (6 ± 2˚C) and at warm (21 ± 2˚C) temperatures. Transmittances were recorded from 380 to 780 nm and at the wavelength with maximum absorbance, which was calculated from the transmittance. The characteristics of the lenses were evaluated by examining changes in the optical properties at colorless and colored states and in the fading rate depending on temperature. The wavelength with maximum absorbance for photochromic lenses at the cold temperature showed a shorter shift than that at the warm temperature. The photochromic properties at the cold temperature were 11.5% lower for transmittance, 1.4 times higher for the change in optical density, and 1.2 times higher for the change in transmittance in the colored and colorless states, optical blocking % ratio, and change in luminous transmittance as compared to those at the warm temperature in the colored state. The fading rates based on the half-life time at the cold temperature were from 2.7 to 5.4 times lower than those at the warm temperature. The fading time until 80% transmittance was 6.4 times longer at the cold as compared to that at the warm temperature. There were significant differences in the optical properties of the photochromic lenses in terms of an absorbance at a shorter wavelength, a lower transmittance, a higher optical density, optical blocking % ratio, and luminous transmittance at the cold as compared to the warm temperature. Hence, it is necessary to provide consumers with information on photochromic optical properties, including the transmittance in colored and colorless states, and the fading rates at temperatures corresponding to the summer and winter seasons for each product.

Effect of Photochromic Contact Lens Wear on Indoor Visual Performance and Patient Satisfaction

“…They found that the improvement in glare disability, glare discomfort, and chromatic contrast was about half of what we had previously seen using similar measures but an activated photochromic lens (improvements around 15% vs. around 30%) showed that the photochromic CL improved the ability resolve the separation of two small bright points of light and that this effect was reduced in magnitude but still apparent even when the photochromic CL was not activated [7]. Interestingly, Alabi et al and Moon et al found, using CL and spectacle lens photochromic bench, respectively, that the temperature can influence both the activation and deactivation of photochromic lenses such that the higher the temperature, the greater the light transmission [11,12]. However, the clinical usefulness or the feasibility of the photochromic CL has not been fully elucidated, except for one study, in an indoor environment [6].…”

“…Corning first introduced photochromic spectacle lenses in 1962 to rectify such disadvantages by filtering in a dose-dependent manner according to the intensity and wavelength of light in the environment [4]. Furthermore, photochromic contact lenses (CLs) have also been reported to be beneficial for reducing these unpleasant visual symptoms, especially under bright light conditions [2,[5][6][7][8][9][10][11][12]. Recently, new photochromic CLs (ACUVUEÒ OASYS with Transitions TM , Johnson & Johnson Vision, Jacksonville, FL, USA) have been approved for clinical use and have become commercially available in Japan.…”

Assessing visual performance during intense luminance changes in virtual reality

“…14 Additionally, to ease the visual discomfort elicited from indoor-outdoor transitions, for example when entering a building on a sunny day, the solution can be photochromic self-tinting lenses. 15,16 However, photochromic lenses have limited usability, as they depend on ultraviolet light and reaction times on average of approximately 210 seconds to switch between states at room temperature, 17 which is too slow for most of the encountered indoor-outdoor transitions. The latest solutions are ultraviolet-light independent electrochromic lenses, 18,19 which have highly variable characteristics regarding their switching times and transmission values.…”