Photometric and psychophysical evaluation of photochromic lenses

Annalaura Piccioli¹, Elisabetta Baldanzi^1,2, and Alessandro Farini^1,2

¹Dipartimento di Fisica e Astronomia,Università degli Studi di Firenze Via Giovanni Sansone 1, 50059 Sesto Fiorentino Firenze, Italy

²CNR-Istituto nazionale di Ottica, largo Enrico Fermi 6 50125 Firenze, Italy

This study presents a photometric and psychophysical evaluation of Transitions GenS photochromic lenses compared to their previous generation, Transitions Gen8. The photometric analysis measured lightness (L*) and color stability during the clearing phase using a spectrophotometer, revealing that GenS lenses fade significantly faster while maintaining better chromatic consistency, especially in the grey tint. Psychophysical tests assessed contrast sensitivity recovery in 25 adult participants (20–35 years old, uncorrected visual acuity ≤ 0 logMAR) using both a printed and a digital version of the Pelli–Robson chart. Results showed that subjects consistently regained contrast sensitivity more quickly with GenS lenses, confirmed by statistical analyses including t-tests (p < 0.001), Bland–Altman plots, and correlation assessments. These findings suggest that the improved transition speed of GenS lenses offers not only measurable photometric advantages but also meaningful benefits in visual performance. © Anita Publications. All rights reserved.
Doi:10.54955/AJP.34.5-6.2025.279-287
Keywords: Photochromic lenses, Contrast sensitivity, Color stability.

Peer Review Information
Method: Single- anonymous; Screened for Plagiarism? Yes
Buy this Article in Print © Anita Publications. All rights reserve

References

1. Nicoletti F, Kaliakatsos D, Ferraro V, Cucumo M A , Analysis of the energy and visual performance of a building with photochromic windows for a location in southern italy, Build Environ, 224(2022)109570; doi.org/10.1016/j.buildenv.2022.109570.
2. Dotsenko A V, Glebov L B, Tsechomsky V A, Physics and chemistry of photochromic glasses, CRC Press), 2020.
3. Ercole F, Davis T P, Evans R A, Photo-responsive systems and biomaterials: photochromic polymers, light-triggered self-assembly, surface modification, fluorescence modulation and beyond, Polym Chem, 1(2010)37–54.
4. Renzi-Hammond L M, Hammond B R, The effects of photochromic lenses on visual performance, Clin Exp Optom, 99(2016)568–574.
5. Hammond B R (Jr), Buch J, Hacker L, Cannon J, Toubouti Y, Renzi-Hammond L M, The effects of light scatter when using a photochromic vs. non-photochromic contact lens, J Optom, 13(2020)227–234.
6. Buch J, Sonoda L, Cannon J, Unexpected vision performance with photochromic contact lenses in normal and low light conditions: An analysis of two randomized trials, J Optom, 16(2023)135–142.
7. Kamiya K, Suzuki S, Fujimura F, Effect of photochromic contact lens wear on indoor visual performance and patient satisfaction, Ophthalmology and Therapy, (2022)1847–1855.
8. Pelli D, Robson J, Wilkins A, The design of a new letter chart for measuring contrast sensitivity, Clinical Vision Sciences, 2(1988)187–199.
9. One-sample and paired-sample t-test, MathWorks, (2024). Available at: https://it.mathworks.com/help/stats/ttest.html (Accessed: 03-07-2024).
10. Bland J M, Altman D, Statistical methods for assessing agreement between two methods of clinical measurement, The Lancet, 327(1986)307–310.