How do blue light glasses work?

Question

What’s the mechanic in transparant blue light glasses and how would they help prevent eye fatigue and headaches?

In: Physics

Answer 1

Clear “blue blocking” lens scam works something like this:

The “blue blocking” glasses come with “blue” LED and a test pad to verify that the glasses do actually work.
If you shine the “blue” LED on the test pad it changes color. If you shine the “blue” LED on the pad through the glasses it does not change color.

But the pad is not responding to blue light. The pad responds to UV light. The LED is actually weak UV LED which also has some bule light in it.
So the test pad just tests that the glasses block UV light.
The glasses of course block UV light (this is normal feature with glasses).