If your cell phone has an LED light on the back for use as a flashlight and taking pictures, you may be able to verify that your solar eclipse glasses are safe.  In my case, I obtained the eclipse glasses a couple of weeks ago and actually tested them that day – by direct sunlight – no clouds.  Sure enough the sun appeared as a very dim yellow disc looking through the glasses. (I was actually surprised how small the sun looked with no flare) After reading about the recall of some solar glasses it occurred to me that my Samsung cell phone has a blinding LED light on the back.  So I decided to try it out on the solar glasses.

First of all, you shouldn’t be able to see anything through solar glasses except a very bright light comparable to sunlight.  The ones I have are totally dark until you look at an extremely bright light up close or the sun.  So I tested them using my cell phone light, the one that is blinding to look at normally.  Below are the photos of the test.  First one is a picture of the cell phone light and the second one is of the solar glasses covering the LED light on the back of my phone.  As you can see, the incredibly bright led light is reduced to a dim, yellowish spot through the glasses.  Since I had tested these glasses using actually direct sunlight, I knew they were safe.

Now this test is assuming your LED light on your phone is almost blinding in the first place.  Most cell phone LED lights are essentially of the same intensity. No this is not a scientific test of course but if you put your cell phone LED against your solar glasses, it should be very dim and virtually not visible.  If the light is very visible through the glasses, they may not be safe to watch the eclipse.  Most reports indicate solar glasses are supposed to have a code on them ISO 12312-2 (sometimes written as ISO 12312-2:2015) which my glasses have – BUT, there are reports that some solar glasses have the code but are NOT safe.  This presents a huge risk for millions of Americans who are going to be relying on their solar glasses to protect them from damaging their eyes.  My advice is use some method to verify your glasses are safe such as the one described here or some other method of intense light through the glasses.  Again, you shouldn’t be able to see anything through the glasses except a very intense brilliant light.