Wake up easier, sleep better
Bright morning light helps reset your circadian rhythm, making it easier to wake up alert and wind down naturally at night.
Light and Health
the evidence
Light is a biological signal
Light doesn't just help you see. It tells your body what time it is. Specialised receptors in your eyes detect brightness and send signals to your brain's master clock, which regulates sleep, alertness, mood, hormone release, and metabolism.
When light exposure is insufficient or poorly timed, this system drifts out of sync, leading to disrupted sleep, lower energy, impaired focus, and long-term health consequences.
For a deeper look at the science of light and circadian health, read founder Nat Martin's piece here: How to Use Bright Light to Improve Your Life →
the evidence
Bright Light for health
The therapeutic effects of bright light are well established. Research into Seasonal Affective Disorder (SAD) first demonstrated that light alone can meaningfully influence mood and energy. Since then, studies have shown benefits extending to sleep quality, cognitive performance, and metabolic health.
A consistent finding across decades of research: around 5,000 lux hours of daily bright light exposure supports optimal circadian function. Timing matters too. Light in the morning has the strongest effect on resetting your internal clock.
Bright light therapy
The problem with current solutions
Traditional SAD lamps can deliver the required intensity, but only if you sit inches away for 30 -60 minutes daily. In practice, few people maintain this routine. Bright light becomes a task rather than part of life.
Total Light Output (lumens)
Phillips ES R63 3W
Beurer TL130 SAD Light
Lumie Task Lamp
Sunday
Sunday delivers 34,500 lumens (30 to 50x more than a typical SAD lamp). That's 10,000 lux at arm's length, enabling you to seamlessly integrate bright light into your routine.
No dedicated sessions. No behaviour change. Just better light where you already spend time.
The science
Why bright light matters for your health
More energy through the day
Daylight-quality light supports sustained energy and helps reduce the afternoon slump we experience under dim indoor lighting.
Sharper focus and clarity
Research shows bright light improves concentration, reaction time, and cognitive performance, whether working from home or in an office.
Lift your mood naturally
Decades of research show bright light is effective for seasonal affective disorder (SAD) and helps regulate mood and emotional wellbeing.
Dr Russell Foster
Circadian Neuroscientist, University of Oxford
I was incredibly impressed by the Sunday Light. It produces a level and quality of light that approximates sunlight, yet its design allows prolonged use that is both comfortable and convenient.
Critically, you do not have to sit next to the device to get the levels of light that will deliver physiological benefits.
The Sunday difference
Daylight quality, not just brightness
Intensity alone isn't enough. Outdoors, sunlight is scattered by the atmosphere, creating soft, diffuse light across the entire sky.
Sunday recreates this effect using a large reflective panel that spreads light across a broad surface. The result: daylight-level brightness that feels natural, not harsh.
The right light at the right time
Your circadian rhythm responds not just to brightness, but to colour temperature. Cool, blue-enriched light signals morning, and warm, amber light signals evening.
Sunday shifts automatically, from 6000K at dawn to 2650K in the evening, aligning your environment with the natural arc of the sun. No manual adjustment. No conscious effort. Just light that follows the day.