I have changed my habits, no reading on the ipad in the evening. I activated Night Shift, set it to 23 hours. When I read I use the night whatever, it is a black screen with white fonts. With filter active the font is yellow. The filters cause a yellow tint over everything. I read about a lot of things you can do that helps like setting the monitor at arms length. I use Firefox and an add on called no squint and I can zoom the background and font. I also get up after 20 to 30 minutes and do something else and blink a lot. I believe this is a real danger or I would not have posted this. It's just like the phones putting out radiation, no one wants to believe it can cause cancer because they don't want to give up their phones. I carried mine in my right pocket for 3 and 1/2 years and had cancer in the right kidney.

I haven't read any books on my New Acer Tablet, but I did notice while playing around with it in Setting that it has a Reading Mode Built-In. It's a Slider to adjust to a level comfortable to you! My Sleep Cycle were all screwed up long before Computers existed.

My sleep cycle was never like this. I read a reg book in bed tonight and I am still wide awake. I don't think anyone really understands what I am talking about. The blue light emits something that can seriously damage your eyes. You need to have a filter and it is not built into the devices. A filter has to be downloaded by the user or by the company. Apple realized the dangers and they downloaded the filter, it took 3 hours. Blue light leads to macular degeneration which leads to blindness. The corneas of my eyes are swollen and very irritated we don't know if it a natural cause or the blue light. I won't say any thing more about this. I should not have said this much. I got a warning from my eye doctor, I paid attention and wanted to warn others.

marci, I'm sorry about your past health problems and I hope the future holds many years of good health for you.

Having said that, I think you're a bit misinformed and perhaps also overly concerned about what you've heard. Sleep issues are addressed not on a computer forum but by seeing a medical doctor who specializes in Sleep Medicine. It's a newer field but properly trained docs are easy enough to find.

From what I've read (triggered by your comments), macular degeneration can have many risk factors but causes aren't confidently understood. You're seeing an ophthalmologist, listen to their advice but don't overreact to what you hear.

There are just far too many people who follow a different path than you have without any problems or ill-effects. What you refer to with such confidence concerning cause and effect aren't experienced by as many people as your view would suggest.

Good luck

I have AMD. I have the wet version in my left eye [required/and may require additional treatment] and the dry version in my right eye [requiring no treatment but continual observation in the event it changes]. Luckily, this struck me at a very advantageous time in medical research. There's a relatively new [and successful] treatment for AMD called Eylea. AMD is actually actively bleeding tiny blood vessels in the back of the eye. Eylea injections stop the bleeding. Instead of losing all the sight in the eye...with vision turning to a black blob...you may only lose a very small area of view. I have what I consider a small grayish circle where I've lost vision...and my right eye compensates. I've adapted very well to this loss but the one side effect that is more annoying to deal with is the loss of depth perception. I continually watch where I put my feet when I'm walking in strange territory.

In any case...I can tell you with a surety...having thoroughly researched this malady...as well as having discussed it with several expert medicos...that blue light does not, has not and will not...in and of itself...cause AMD.

I am an inveterate reader, writer/ researcher. I don't own an iPad or similar reading tool but I rarely go to sleep at night without at least 2 hours of book reading [in bed] under my belt. And...yes...that can cause eye strain if you don't have proper lighting
and the font is very small....but it will not lead to AMD. I do, however, spend a lot of time reading/writing on my PC. That, too, will/can cause eye strain if I don't have the proper lighting and I don't increase the font size to an easily readable number. But, again, it will not cause AMD and no blue light has caused me any harm.

If you have some other disease such as diabetes or high blood pressure...or physical impairments such as cataracts, a detached retina or other ocular damage...or you take daily doses of aspirin or are/were a smoker...these may contribute to AMD. Actually, probably the biggest contributor...segregating those mentioned above...is old age. Like most body parts...our eyes do wear out in time.

Your doctor, as Snidely mentioned above, is equipped to advise you where these issues are concerned. I, personally, inherited the genetic predisposition for AMD. I have no other contributing factors other than I am in mid to late 70's and I've used my eyes excessively throughout my lifetime for copious amounts of detailed work and enjoyment.

Check out some of these sites. I have read enough about this to know it's true. I will not use my Ipads again.

Blue light emissions.