??blue light and alertness

Found an article about blue light having the effect of making people stay awake, here

So... if I had an array of blue lights shining at me I wouldn't fall asleep as readily? Sounds useful, but I'll stick to my stockpile of Jolt gum, Penguin mints, Bawls mints, XTZ mints, Red Bull, and Monster.

Interesting. I gather that these newly discovered receptors play a role in modulating the melatonin level in the bloodstream.

Interesting. I've got a projection clock that projects blue numbers onto my ceiling. I've always thought the reflected blue light was soothing and helped me sleep. Maybe it's actually keeping me awake longer since I'm staring at the ceiling... :thinking:

I have a new clock in my room and it's got a REALLY bright blue neon around it. I noticed that it does keep me going when it's the only light on. I actually thought about that the other day because sunlight does have UV/Blue in it but yet incandecents put out more IR and they always make me go to sleep with their warm hues...

Here is an article from an aggregator website reporting on possible benefits of blue light.

https://newatlas.com/blue-light-psychosocial-stress/52151/

bobbagum said:

Found an article about blue light having the effect of making people stay awake, here

Click to expand...

Thanks!

I sometimes drive when Im tired, and sometimes resort to Coffee in that situation. Maybe a Blue LED would be a useful addition to my Xmas wish list..

Could it be that cars with blue dash lights (e.g. VW Passat) increase driver alertness and reduce driving fatigue?



on a separate subject, it is possible that eliminating red and green light, speeds up recovery from stress.
(Imo the following article title is not quite accurate):
Blue lighting accelerates post-stress relaxation:

"In this paper we have shown that blue lighting accelerates the post-stress relaxation in comparison with conventional white.
...
white lighting was produced as the combination of the three sets of LEDs (red, green and blue). However, the blue one was obtained as the suppression of red and green LEDs ceteris paribus. The set of blue LEDs was the only light source in common during the whole relaxation session and paradoxically, whatever differences found in the comparison of blue to white, cannot be due to this wavelength, but the absence of green and red. "


based on the above, a more accurate title might be:
Absence of red and green light, speeds up recovery from stress:

KITROBASKIN said:

Here is an article from an aggregator website reporting on possible benefits of blue light.

https://newatlas.com/blue-light-psychosocial-stress/52151/

Click to expand...

I wouldn't put much faith in the findings described in that study personally. It was only 10 subjects and there is an overwhelming amount of studies that have found that blue light is far more harmful then good for you overall. In fact, it has so many detrimental effects to your health that the American Medical Association has even recommended that cities around the world stop using cool white LED's(high in blue light) for street lighting. People who like cool white flashlights probably should heed this warning as well.

http://www.cnn.com/2016/06/21/health/led-streetlights-ama/index.html

Tachead said:

the American Medical Association has even recommended that cities around the world stop using cool white LED's(high in blue light) for street lighting

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yes the negative effects of blue light is that it disrupts the sleep cycle of residents, when using cooler and or brighter streetlights..

otoh, when trying not to fall asleep at the wheel, Blue Light helps keep drivers awake

so it depends whether you want to sleep or stay awake

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http://volt.org/lessons-learned-davis-ca-led-streetlight-retrofit/

the city made the decision to use Leotek 27-watt/2,800 lumens fixtures with 4,000K CCT color temperature.

By May, negative public reaction to the conversion project precipitated a review

in October 2014, the decision was made to replace 650 of the already installed fixtures in residential areas and all remaining LED fixtures with Leotek 19-watt Green Cobra Jr., producing approximately 1800 lumens and 2,700K CCT.

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http://www.cnn.com/2016/06/21/health/led-streetlights-ama/index.html

In the case of white LED light, it is estimated to be five times more effective at suppressing melatonin at night than the high pressure sodium lamps (given the same light output) which have been the mainstay of street lighting for decades. Melatonin suppression is a marker of circadian disruption, which includes disrupted sleep.
…
the AMA "encourage the use of 3000K or lower lighting for outdoor installations such as roadways.

===

For a driver interested in staying awake, it sounds like a "regular" Cool White LED flashlight might help... as it has tons of blue, apparently..

Tachead said:

I wouldn't put much faith in the findings described in that study personally. It was only 10 subjects and there is an overwhelming amount of studies that have found that blue light is far more harmful then good for you overall. In fact, it has so many detrimental effects to your health that the American Medical Association has even recommended that cities around the world stop using cool white LED's(high in blue light) for street lighting. People who like cool white flashlights probably should heed this warning as well.

http://www.cnn.com/2016/06/21/health/led-streetlights-ama/index.html

Click to expand...

Usually when I am using a flashlight, I want to stay awake. I fall on the trails far less than when I am awake.

"Overwhelming amount of studies showing blue light bad" ... where? If you are near the time when you sleep then blue light is not what you want to be exposing yourself too. One could argue for an increased glare response too ... which is good and bad. Intense short wavelengths long term can cause degradation of the eye ... and then again there is far more blue radiation in sunlight than any artificial light given how bright sunlight is.

The AMA release was bordering on professional ignorance. 1) Drivers need to stay awake. 2) People have blinds on their windows that block out streetlights.

jon_slider said:

http://volt.org/lessons-learned-davis-ca-led-streetlight-retrofit/

the city made the decision to use Leotek 27-watt/2,800 lumens fixtures with 4,000K CCT color temperature.

By May, negative public reaction to the conversion project precipitated a review

in October 2014, the decision was made to replace 650 of the already installed fixtures in residential areas and all remaining LED fixtures with Leotek 19-watt Green Cobra Jr., producing approximately 1800 lumens and 2,700K CCT.

Click to expand...

I will go out on a limb and say of those 36 negative comment, 35 of them were born of pure ignorance. A 90W HPS produces a lot of light. They were replacing them with lights with much lower lumen levels. The only way you can do that is to 1) Have a better lumen maintenance (brighter and end of life, not start), and 2) Place far more of the light where it needs to be.

Here is the claims, "producing too much glare and light trespass, increasing skyglow and light pollution"

While the glare claim is quite likely valid, the trespass, skyglow and light pollution was likely not at all true given the way lower amount of lumens AND that far few lumens were going outside the target area (road and sidewalk). Unfortunately, this is what happens when you let politicians make technical decisions.

I have no doubt the 2700K was better received in the residential areas, it is a more pleasant light at typical low lighting levels used for street lights. Of course, while there is limited value in higher CCT lights at highway speeds, at the low speeds of residential streets, the higher CCT lights would have provided improved peripheral vision .... i.e. so your kid, dog, cat, etc. was not run over.

Makes sense. When I was strugging with insomnia I had certain lights for therapy. Cooler and brighter white for when I first got up in the morning to restablish my circadian rythm and let my brain know its time to be awake. And then much warmer and lower levels of light in the evening to let me brain know it was time to go to sleep. I'm sure its much more technical than that. But, I still only use warm colored lights within an hour or so before bed time. Never cool tints or blue light.

Yes, it's pretty well known that blue wavelengths from LED lights/backlights interfere in myriad ways with your sleep cycle (hence phones have "night mode" now) so I guess if you want to remain alert and suffer the significant health repercussions of a totally messed up circadian rhythm and lack of sleep then blue light might help. YMMV!

Lumen83 said:

When I was strugging with insomnia I had certain lights for therapy. Cooler and brighter white for when I first got up in the morning to restablish my circadian rythm and let my brain know its time to be awake. And then much warmer and lower levels of light in the evening to let me brain know it was time to go to sleep..

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Phillips Hue is a Home LED lighting product I tried.
I set it up as a wake up alarm, the lights in my bedroom would come on as an orange glow in the morning, that got brighter. Then 30 minutes later, they would turn on to Cool White, which made it very difficult to stay asleep. At the end of the day, I set the lights to lower brightness and warmer colors.. It is a very versatile system, with timers, schedules, and even a web app. Its rather clever, there is even geofencing, it can turn the lights on and off when I leave and come back home..

they have "light recipes" for reading, studying, relaxing, working.. that each vary the color temperature and brightness.