What it’s for
- Circadian timing and selected sleep problems
Timed exposure to a bright artificial light, usually to influence sleep-wake timing or mood.
Purpose, evidence and practical considerations.
Reviews find benefits for some sleep outcomes, with variation between studies. Timing and the person’s underlying sleep pattern matter; a fixed morning schedule is not suitable for every condition.
Confidence: moderate
Possible effects include eyestrain, headache, agitation, nausea and sleep disruption if mistimed. Bipolar disorder, retinal disease, migraine or photosensitising medicines warrant clinician input. Do not stare directly into the light; follow the device distance and timing instructions.
Bright light reaching the eyes signals intrinsically photosensitive retinal ganglion cells and can shift circadian timing. Morning exposure usually advances the sleep-wake rhythm, while evening exposure can delay it; timing, spectrum, distance and intensity all matter.
The evidence on this page does not automatically apply to:
How people use it, with their schedules, context and original sources.
10,000 lux
Manufacturer guidance and observed protocol patterns, kept separate from evidence of benefit.
Session and timing patterns reported in public protocols; these are observations, not instructions. Private and hidden usage is excluded.
daily
These share a protocol with this intervention. This does not establish that they work together or are suitable alternatives.
10,000 lux, 6 min · Daily · on waking (~5 a.m., before sunrise)