500 degrees of aspherical, how much is the center of the thickness of 1.56,1.60,1.67,1.7,1.74 lens ? Recently, I confused what the difference between 1.6 non-spherical and aspherical previous 1.56? They almost look the same?

They are based on the refractive index to points. The higher refractive index, the more thin lenses.