Circadian Science, Explained
Research-backed articles on sleep, light, display health, and building better habits around your biological clock.
Why Night Shift Isn't Warm Enough (And What Actually Works)
You dragged the warmth slider all the way to the right. You're still wide awake at 1 AM. Here's why Night Shift doesn't do enough, and what the science says you need instead.
Read article →Why Apple's Night Shift Isn't Enough
Night Shift is better than nothing. But a fixed timer and a simple warm tint cannot replicate what solar-phase tracking does for your circadian clock. Here is what the research shows.
Read article →Blue Light and Sleep: What the Research Actually Says
The link between short-wavelength light, melanopsin activation, and melatonin suppression is well-established. We walk through the key studies and explain the underlying biology.
Read article →Melanopic EDI Explained: Why Lux Is the Wrong Metric
The CIE S 026:2018 standard introduced a better way to measure circadian light exposure. If you only know about lux and color temperature, you are missing half the picture.
Read article →The Morning Light Problem Nobody Talks About
Blocking blue light at night is only half the equation. Morning light is what anchors your SCN to the solar day, and most people who work from home are chronically deficient.
Read article →PWM Flicker and Headaches: The Hidden Cause of Screen Fatigue
Most laptop and monitor backlight dimming uses pulse-width modulation, which rapidly switches the backlight on and off. For many people, this invisible flicker causes headaches and eye strain.
Read article →Eye Health for Developers: A Practical Guide for Late-Night Coders
Developers spend more screen time than almost any other profession, often late into the night. Here is a research-grounded toolkit for protecting your eyes and your sleep without breaking your flow.
Read article →The 20-20-20 Rule: Why Most People Fail at It (and How to Fix That)
The American Academy of Ophthalmology recommends looking at something 20 feet away for 20 seconds every 20 minutes. Simple in theory. Almost nobody does it consistently. Here is why, and what actually works.
Read article →Your Circadian Rhythm Is Running Your Productivity (Whether You Know It or Not)
Sleep is the obvious link, but circadian timing affects cognitive performance, mood, metabolism, and immune function throughout the day. The research is deeper than you might think.
Read article →Circadian Rhythm Disorders: Signs You Are Out of Sync
Circadian rhythm disorders affect millions and are routinely misdiagnosed as insomnia or laziness. Learn the six types, the warning signs, and evidence-based strategies to get back in sync.
Read article →Screen Dimmer for Better Sleep
Screen dimmer better sleep: dimming adds about 4 minutes, color filtering adds about 11 minutes. See the science, compare tools, and build an effective evening routine.
Read article →How Screen Time Before Bed Destroys Sleep Quality
Screen time before bed delays melatonin onset by 1.5 hours, reduces REM sleep, and produces next-day cognitive deficits. Here is the evidence and what to do about it.
Read article →Best Monitor Settings for Eye Health in 2026
Optimal monitor brightness, contrast, color temperature, and refresh rate settings to reduce eye strain and protect circadian health. Evidence-based recommendations.
Read article →Color Temperature Explained: What Kelvin Means for Your Screen
What color temperature (Kelvin) means for displays, why 6500K is standard, how lower Kelvin protects your circadian rhythm, and what different temperature settings look like.
Read article →Dark Mode vs Blue Light Filter: Which Actually Protects Your Eyes?
Dark Mode and blue light filters serve different functions. Dark Mode reduces luminance. Blue light filters reduce melanopic stimulation. Here is when to use each, and why you need both.
Read article →Can Blue Light Cause Headaches? What the Research Says
Blue light from screens can trigger headaches through neural pathway activation, PWM flicker, and circadian disruption. Here is what the research actually shows and what works.
Read article →Biohacking Sleep with Light Management: The Complete Protocol
Light is the master circadian zeitgeber. A biohacker's guide to morning light exposure, melanopic EDI targets, evening light hygiene, and sleep optimization.
Read article →The Huberman Blue Light Protocol: What It Says and How to Implement It
Andrew Huberman's light protocol: morning bright light, evening dim light, red filters after sunset. How to automate it with CircadianShield.
Read article →Screen Dimmer for Gaming: Reduce Eye Strain Without Losing Color Accuracy
Screen dimmer gaming guide: reduce eye strain without sacrificing color accuracy. Learn melanopic EDI, Kelvin settings, and CircadianShield's Gaming mode.
Read article →Screen Dimmer Night Reading: The Right Settings for Eye Comfort and Circadian Safety
The best screen dimmer night reading settings go beyond brightness. Learn the Kelvin, melanopic EDI, and preset combos for e-books, code, and web browsing.
Read article →Best Blue Light Filter Software Mac: Why f.lux Isn't Enough in 2026
The best blue light filter software mac users need goes beyond basic color temperature. Here's the science gap f.lux and Night Shift leave open.
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