Blue Light Tester Card

Charger la vidéo:
  1. Place the testing card on a flat surface.
  2. Shine the testing light on the test area (white box).
  3. It should leave a purple mark wherever you shine the test light.
  4. Take the pair of glasses, facing toward you, and place the lens in front of the test area.
  5. Shine the test light through the glasses lens.
  6. Note the reduction of purple markings.