Multi-coated means it prevents all sorts of scattering and reflection of light which results in minimizing the risk of light loss and also gives you a great image clarity and brightness. As per the information, the non-coated one leads to a loss of 1.5% of light, while one coated layer results to loss of 1.5%. The multi-layered coating prevents high loss of light reflection like 0.25% of light. The multi-coated means it is the fastest level of light transmission and giving excellent image clarity.