What are anti-reflective lens

[glass frame]

On the surface of this lens is coated a thin layer of magnesium fluoride in order to prevent reflection by the strong light, and enable wears clearer scenery without the interference of strong light. To examine whether your cheap eyeglasses is the anti-reflective lens, you can let the eyeglasses directed at light source, if you can see purple reflective light, it can be said that the lens is really coated anti-reflective protective material.