Projecting film and method of forming the same

A projecting film enables adhesion to a reflecting film 44 made of an inorganic material to be improved, and alteration of optical properties of the reflecting film 44 to be prevented. A method is provided for forming such a projecting film that enables the surface roughness to be controlled freely through few manufacturing steps. A sol-form application liquid in which are mixed metal compounds and solvent(s) is prepared, the prepared sol-form application liquid is applied onto a glass substrate 40 to form a mixed layer 41 on the glass substrate 40, and the mixed layer 41 on the glass substrate 40 is dried, thus evaporating off the solvent(s), and hence bringing about phase separation into an upper layer and a lower layer, whereby an internal scattering layer is formed.