Display-driven optical stimuli underpin a major class of clinically validated digital therapeutics (DTx) now expanding from neuropsychiatric disorders to chronic diseases. The display’s optical characteristics—spectral power distribution, luminance, contrast, and temporal modulation—therefore define the delivered dose of these software-based interventions. In this context, blue-rich emission in the 450–480 nm band, particularly with evening exposure, can suppress melatonin via melanopsin-mediated intrinsically photo-sensitive retinal ganglion cell (ipRGC) pathways and perturb circadian timing, potentially attenuating therapeutic efficacy. This review summarizes clinical evidence for display-enabled DTx across major indications and synthesizes mechanistic and experimental data linking blue light to sleep and circadian disruption, with downstream mood, cognitive, cardiovascular, and metabolic effects, as well as increased risk of cancer and skin damage. This review distinguishes wavelength-dependent hazards by separating retinal photochemical risk in the roughly 415–450 nm range from circadian-disruptive melanopic effects in the 450–480 nm range, informing spectrum optimization for therapeutic use. It then synthesizes mitigation strategies spanning display emitter spectrum engineering, optical filtering or conversion films, and software controls such as color temperature tuning, high-frequency dimming, metameric spectrum design, and personalized circadian lighting. The review concludes with design, prescription, and standards considerations to align display output with therapeutic intent.
Wonki Hong (Mon,) studied this question.