METHOD OF MEASURING THICKNESS OF FILM AND METHOD OF MANUFACTURING GLASS OPTICAL ELEMENT

PROBLEM TO BE SOLVED: To provide a highly versatile method of measuring a thickness of a film for simply measuring the thickness of a film formed on a base material. SOLUTION: In the method of measuring a thickness of a film formed on a base material, a test film is formed on a test base material with a surface reflectance R0to light of wavelength λnm, a surface reflectance R' of the test film to the light of wavelength λnm is measured two or more times while changing the thickness of the test film, thereby a relational expression between a thickness of the test film and a variation of the surface reflectance (R'-R0) is directed, then a surface reflectance R of the film of an object to measure the thickness to the light of wavelength λnm is measured, and the thickness of the film of an object to measure the thickness is determined by applying the difference (R-R0) between the surface reflectance R and the surface reflectance R0of the test base material to the relational expression as a variation of the surface reflectance. COPYRIGHT: (C)2011,JPO&INPIT