F.lux
 | |
| Developer(s) | Michael Herf, Lorna Herf |
|---|---|
| Initial release | February 2009 |
| Stable release |
Windows: v3.9 Mac OS X: build 23[1] Linux: -- iOS: 0.985[2] |
| Development status | Active |
| Operating system | Microsoft Windows, Linux, Mac OS X, iOS |
| Available in | English |
| License | Proprietary, with free download. (with patent claim) |
| Website |
stereopsis.com/flux/ justgetflux.com |
f.lux is a computer program developed by Michael and Lorna Herf. It adjusts a computer display's color temperature according to its location and time of day, based on a user specified set of longitude and latitude geographical coordinates.
The program was designed to reduce eye strain during nighttime use and to prevent disruption of normal sleep patterns.
Compatibility
f.lux is available on all major operating systems, including Microsoft Windows, OS X, and Linux.
f.lux also is available on the iPhone, iPad, and iPod Touch, although it requires the device to be jailbroken. The developers also are working on a version for the Android operating system.[3]
Theory
f.lux is based on the idea that adjusting the color temperature of the display to match the current time of day will not inhibit the secretion of melatonin during nighttime that is involved in Circadian rhythms, thus allowing the user to sleep with ease. Bright and blueish lights, such as natural sunlight, inhibit the creation of melatonin in the brain to signal the beginning of the day.[4] Most computer, tablet, and touch telephone displays, however, also emit a blue light that triggers this inhibition,[5] affecting the user's ability to sleep and potentially disrupting the user's sleep cycle. Red light does not interfere in the natural cycle. When nighttime arrives, f.lux automatically adjusts the color temperature (making whites appear reddish or salmon), thus reducing the display's brightness to match natural light cycles. The change is noticeable at first, but turns imperceptible after a few seconds.
Configuration
f.lux automatically calibrates the computer or device display's color temperature to the time of the day. The user also has the option of choosing a color preset or disabling f.lux for an hour and returning the screen to its normal calibration. The software offers five preset color settings on OS X: candle, tungsten, halogen, fluorescent, and daylight.[3] For Microsoft Windows, the halogen, fluorescent, and daylight settings are available—as well as Incandescent on beta.
The software requires the device's location in order to determine its local sunrise and sunset. Currently the program does not work for locations that are above 65° North.
See also
References
- ↑ http://justgetflux.com/mac/macflux.xml
- ↑ http://cydia.saurik.com/package/org.herf.flux
- ↑ 3.0 3.1 f.lux: F.A.Q
- ↑ Kubota T, Uchiyama M, Suzuki H, Shibui K, Kim K, et al. (2002). "Effects of nocturnal bright light on saliva melatonin, core body temperature and sleep propensity rhythms in human subjects.".
- ↑ Cajochen C, Frey S, Anders D, Späti J, Bues M, et al. (2011). "Evening exposure to a light-emitting diodes (LED)-backlit computer screen affects circadian physiology and cognitive performance.".