讨论了单层过渡金属超薄膜以及它与介质膜组成的多层膜的光学特性，对它们进行了定量的分析，并以实例说明了过渡金属超薄膜在中性分光镜、窄带高反滤光片等方面的应用。

Transition metallic thin films with n≈k are characterized. The optical properties of transition metallic ultrathin films and the multilayer coatings and other films are quantitatively analyzed, and their applications in neutral beam splitters and in reflection filters of narrow bandwidth and high reflectivity are discussed.