Are you struggling to fall asleep? Do your kids become hyperactive after using tablets before bedtime? If you're using smartphones or tablets in the evening or are sensitive to light during migraines, Twilight might be the solution for you!
Recent research indicates that exposure to blue light before sleep can disrupt your natural circadian rhythm, leading to difficulties falling asleep. This is due to a photoreceptor in your eyes called Melanopsin, which is sensitive to blue light in the 460-480nm range. This sensitivity can suppress Melatonin production, a crucial hormone for maintaining healthy sleep-wake cycles. Studies have shown that reading on a tablet or smartphone for a few hours before bed can delay sleep by about an hour.
The Twilight app adjusts your device's screen to the time of day, filtering out blue light after sunset and applying a soothing red filter to protect your eyes. The filter's intensity is smoothly adjusted based on your local sunset and sunrise times. Twilight is also compatible with Wear OS devices.
Documentation
Learn more about Twilight at http://twilight.urbandroid.org/doc/.
Get More from Twilight
1. Bed Reading: Twilight offers a more pleasant reading experience at night by allowing the screen's backlight to be dimmed far below what standard controls permit.
2. AMOLED Screens: We've tested Twilight on AMOLED screens for five years without signs of depletion or over-burning. Proper configuration reduces light emission through dimming and provides a more uniform light distribution, potentially extending the life of your AMOLED screen.
Basics on Circadian Rhythm and the Role of Melatonin
Explore further at:
- http://en.wikipedia.org/wiki/Melatonin
- http://en.wikipedia.org/wiki/Melanopsin
- http://en.wikipedia.org/wiki/Circadian_rhythms
- http://en.wikipedia.org/wiki/Circadian_rhythm_disorder
Permissions
- Location: Used to determine your current sunset and sunrise times.
- Running Apps: Allows stopping Twilight in selected apps.
- Write Settings: Enables setting the backlight.
- Network: Accesses smart light systems (e.g., Philips HUE) to shield your household from blue light.
Accessibility Service
To filter notifications and lock screens, Twilight may request enabling its Accessibility Service. This service is used solely to enhance screen filtering and does not collect personal information. For more details, visit https://twilight.urbandroid.org/is-twilights-accessibility-service-a-thread-to-my-privacy/.
Wear OS
Twilight syncs with your Wear OS screen, allowing control over filtering through a "Wear OS Tile".
Automation (Tasker or Other)
For automation details, see https://sites.google.com/site/twilight4android/automation.
Related Scientific Research
- Amplitude Reduction and Phase Shifts of Melatonin, Cortisol and Other Circadian Rhythms after a Gradual Advance of Sleep and Light Exposure in Humans, Derk-Jan Dijk, & Co, 2012
- Exposure to Room Light before Bedtime Suppresses Melatonin Onset and Shortens Melatonin Duration in Humans, Joshua J. Gooley, Kyle Chamberlain, Kurt A. Smith & Co, 2011
- Effect of Light on Human Circadian Physiology, Jeanne F. Duffy, Charles A. Czeisler, 2009
- Efficacy of a single sequence of intermittent bright light pulses for delaying circadian phase in humans, Claude Gronfier, Kenneth P. Wright, & Co, 2009
- Intrinsic period and light intensity determine the phase relationship between melatonin and sleep in humans, Kenneth P. Wright, Claude Gronfier & Co, 2009
- The Impact of Sleep Timing and Bright Light Exposure on Attentional Impairment during Night Work, Nayantara Santhi & Co, 2008
- Short-Wavelength Light Sensitivity of Circadian, Pupillary, and Visual Awareness in Humans Lacking an Outer Retina, Farhan H. Zaidi & Co, 2007
