To inexpensively form microlenses as an optical system for condensing of a liquid crystal display panel used in a liquid crystal projector by a simple stage.

An aluminum film 21 is formed atop an upper substrate 2 provided with color filters, etc., on the rear surface and prescribed resist patterns 22 for forming light shielding films (black masks) 11 are formed thereon. When an anodic oxidation is executed next, the aluminum film 21 exposed via the apertures 23 of the resist patterns 22 are anodically oxidized and is changed to a transparent anodic oxide (Al2O3). In addition, the volume thereof is increased to a planoconvex shape by the anodic oxidation, by which the planoconvex microlenses 10 are formed. On the other hand, the aluminum film 21 under the resist patterns 22 is not anodically oxidized and the light shielding films 11 are formed by the aluminum film 12 which is not anodically oxidized. This method is applicable to two-dimensional image sensors, etc., as well.