A paper published August 18 in Cell Reports Medicine reports that supplemental indigo light — short wavelengths abundant in outdoor daylight but poorly represented in conventional white LEDs — prevented the axial eye growth that produces myopia in tree shrews, an established model for studying myopia with several eye characteristics similar to humans. Led by researchers at Cincinnati Children's and the University of Alabama at Birmingham, the study identifies an effective band roughly 419–446 nm and frames a hypothesis for the broader "myopia boom": modern indoor lighting may differ from daylight in a biologically consequential way even when the room looks adequately illuminated.
The architectural claim is about spectral power distribution, not brightness. Standard white LEDs can deliver plenty of photopic light for seeing while underrepresenting portions of the outdoor spectrum that may matter for nonvisual pathways involved in eye growth. The authors point next toward testing indigo-enriched lighting in daycare settings. Until those human studies exist, this remains an animal finding and a design hypothesis — not a specification for residential bulbs.
The researchers also have a commercial interest in the technology: Grytz and Lang are named inventors on pending patents for related lighting devices, while Grytz is founder and chief science officer of Electric Indigo, a UAB startup in which the university holds an ownership interest.