The significance of optical studies of art objects is discussed, and the history and present state of these studies in Europe, America and Japan is briefly summarized. The methods and equipment considered include: X-ray radio graphy ultra-violet rays, intra-red rays, the microscope and beta-rays. Sculpture of wood, dry-lacquer, clay and giltbronze: painting on wood, silk and paper; calligraphy; and handicrafts such as ceramics, are various types of Oriental antiquities to which these methods have been applied. -- AATA