How to determine if your lenses are high quality?

Currently, factories classify lenses into two grades: Grade A and Grade B. Our company just produces only Grade A lenses. So how do you determine if the lenses you purchase are good quality( Grade A lenses)? First, let’s look at the areas of the lens: Lenses typically have three areas: A, B, and C. Area A is a … Continue reading How to determine if your lenses are high quality?