Reflectance reducing film and method of forming same on glass substrate

A method of forming on a glass substrate a silicon dioxide film having a thickness of about 60 to 160 nm and a refractive index of 1.21 to 1.40 and being minutely rough such that the film has micro-pits and/or microscopic land regions, at least one of each micro-pit and each land region having a diameter of 50 to 200 nm, the method comprising the steps of:

• (a) preparing at least two sols respectively from at least one compound so as to disperse in said at least two sols at least two polymers of said at least one compound, said at least one compound being selected from the group consisting of silicon alkoxides and silicon acetylacetonates, said at least two polymers having different average molecular weights;
• (b) mixing said at least two sols together with a solvent so as to prepare a coating solution;
• (c) applying the coating solution to the glass substrate so as to form a sol film on the glass substrate;
• and
• (d) heating the glass substrate and the sol film so as to transform the sol film into a gel film which has a minutely rough surface having micro-pits and/or microscopic and regions.