Summary
This thesis presents a novel contact lens technology using plasmonic silver nanoparticles (AgNPs) to selectively block harmful blue-light wavelengths (400–450 nm) while transmitting beneficial wavelengths needed for circadian and pupillary functions. The approach offers a practical wearable solution for the 71 million contact lens users worldwide who currently have no commercially available UV and blue-light protective option.
Key Findings
- AgNPs were synthesized with tunable localized surface plasmon resonance (LSPR) peaks between 400–450 nm and full width at half maximum (FWHM) values of less than 45 nm, enabling precise selective blue-light filtering.
- Silica-coated AgNPs integrated into commercial etafilcon contact lenses demonstrated blue-light filtering while maintaining transparency across visible wavelengths.
- NP-integrated lenses showed stability after autoclaving, UV exposure, natural sunlight exposure, and room-temperature storage, supporting commercial viability.
- No commercially available contact lenses currently offer both UV and blue-light protection despite over 71 million contact lens wearers worldwide.
Categories
Eye Health & Vision: The paper addresses retinal damage, AMD, and photophobia risks from blue light (HEV) and develops a contact lens solution to selectively filter harmful wavelengths.
The Science of Light: The work engages with spectral sensitivity of blue light wavelengths relevant to pupillary light reflex, melatonin regulation, and circadian rhythm, motivating selective rather than total blue-light filtering.
Sleep & Circadian Health: The thesis explicitly accounts for the role of specific blue-light wavelengths in melatonin regulation and circadian entrainment, designing filters to preserve these beneficial wavelengths.
Author(s)
H Krishnakumar
Publication Year
2018
Related Publications
Eye Health & Vision
- Diminished pupillary light reflex at high irradiances in melanopsin-knockout mice
- Genetic reactivation of cone photoreceptors restores visual responses in retinitis pigmentosa
- Melanopsin and rod–cone photoreceptors play different roles in mediating pupillary light responses during exposure to continuous light in humans
- Characteristic patterns of dendritic remodeling in early-stage glaucoma: evidence from genetically identified retinal ganglion cell types
- Intrinsically photosensitive melanopsin retinal ganglion cell contributions to the pupillary light reflex and circadian rhythm
The Science of Light
- Phototransduction by retinal ganglion cells that set the circadian clock
- Color appearance models
- The mammalian circadian timing system: organization and coordination of central and peripheral clocks
- Diminished pupillary light reflex at high irradiances in melanopsin-knockout mice
- Melanopsin is required for non-image-forming photic responses in blind mice
Sleep & Circadian Health
- Phototransduction by retinal ganglion cells that set the circadian clock
- The mammalian circadian timing system: organization and coordination of central and peripheral clocks
- The two‐process model of sleep regulation: a reappraisal
- Melanopsin is required for non-image-forming photic responses in blind mice
- Strange vision: ganglion cells as circadian photoreceptors