The experiment compared 6.5 hours of 460-nm and equal-photon 555-nm light; short-wavelength light produced approximately twice the phase delay and melatonin suppression.
High Sensitivity of the Human Circadian Melatonin Rhythm to Resetting by Short Wavelength Light
Article title
The experiment compared 6.5 hours of 460-nm and equal-photon 555-nm light; short-wavelength light produced approximately twice the phase delay and melatonin suppression. Supports wavelength sensitivity under laboratory lighting, but does not itself establish a universal 90-minute delay from phones.