Check your glasses for unwanted blue light transmission using this personal test kit.
To use, place glasses on top of test strip, then illuminate at close range using included light for 10 secords. If test strip turns purple, the glasses are transmitting blue light. The intensity of the spot will vary depending upon the blue light transmission of the lenses. Illuminator wavelength: 400 nanometers. Battery type: 3x LR41 Dry Alkaline Cell. Reusable.