> The time of day of any potential violet-light therapy for myopia also could matter.
Before anyone rushes to change desktop backgrounds, any effect might involve actual "violet" wavelengths of light (380nm) [0] as opposed to mix of typical LED-reds and LED-blues that are visually similar. Plus then you have a new risk, with blue light at night affects circadian rhythms.
I suppose one could create their own light-emitting source, but I'd be afraid of accidentally scorching my retinas with strong invisible UV.
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