Fluorescent Lights = sleepiness?

[sanddrag]

Do fluorescent lights make you sleepy? I'm convinced it is what makes me sleepy sometimes. Is there some sort of scientific reasoning that these lights either do or do not make people sleepy? I think they do because of something about the frequency of which they ocsillate on and off. What do you think?

[CmptrGk]

my old english teacher said something about this. they turn off an on rapidly so your eyes are constantly adjusting to light and dark. idk if this is actually why, but this is what he told us.

[KenWittlief]

they do blink 60 times a second

they can cause eye stress, and when you move your eyes around the room you get a pulsed view, not steady light

there are some florescent lights that have more persistance or run at a higher frequency, so they dont flicker/blink as much.

[tiffany34990]

all i know is i hate them when i have a migrane... because of the constant flickering and the power of them..

all wellz... and they are all over the place really...

[Andy A.]

As an aside, if you ever get the chance, you can use a photo resistor and an oscilloscope and see the rise and fall of the light intensity in a room with fluorescent lights. It's one of those oscilloscope 101 things that you just never forget. I remember thinking how neat it was that this tool was seeing something right in front of me that I couldn't.

As for making you sleepy, I've suspected the same thing. In any case, I've always felt like the light was to blue, and your brain isn't seeing the right frequency of light to make it think that its daytime. Theres nothing like full sunlight.

-Andy A.

[KenWittlief]

something else you can do, power a small fan with a variable power supply, and look through the blades at the fluorescent lights in the room.

If you get the speed just right it looks like the lights are slowly turning on and off. And if different banks of lights are powered on different phases of the power coming into the building (220 or 3 phase power) you can tell which ones are wired together, because they pulse together.

[Hutch]

Yep... Even this with an inductor to try to stabilize it some (without it they would just go off). This is one of those things though that I don't know how people notice O_o. Kind of like seeing my CRT refresh, just never had that problem.

[Andy A.]

Originally Posted by Hutch

Yep... Even this with an inductor to try to stabilize it some (without it they would just go off). This is one of those things though that I don't know how people notice O_o. Kind of like seeing my CRT refresh, just never had that problem.

Just think how cats must feel! Their vision is so 'fast' they can see the image on a TV screen being drawn. I'm sure they can see all kinds of flicker in our lights, not to mention what they must hear.

Perhaps you've been blessed with vision thats just a touch slower then others, so you don't have to notice that little flicker in your monitor or lights. At 85 Hertz, I can't notice any flicker in my monitor. By 65Hz it is noticeable and at 60Hz it's just plain aggravating. I guess somewhere around 60Hz is the highest frequency that my eyes can register. I wonder how big of a spread there is in humans?

Makes you appreciate just how lame our senses are.

-Andy A.

[KenWittlief]

stand about 10 to 20 feet away from your CRT monitor, and chew on some crushed ice

then try to figure out why your monitor wacks out with each crunch of the ice between your teeth!

?

you can also see this if you walk quickly though a room with CRT monitors. With each step the monitors appear to glitch.

[KTorak]

MY eyes do weird things...a lot of the time I can see my monitor flicker at 85Hz.

[Steve W]

At work I have had a lot of the lights pulled. I was getting headaches on a more consistent basis until I removed a lot of the lights. Much better now. I can't spend much time in stores with fluorescent lights because they hurt my eyes.