How can I test blue light glasses to see if they work?

To test blue-light filtering lenses, you can use a blue light torch/laser that emits a minimum wavelength of 420nm, and see how much of the light is filtered when beamed through the lens of the glasses.

We know, we know... everyone carries this laser in their back pockets 🤓 

Tip: Need more help? Click 👉 here to know more about blue light lenses.