Unusual structural colors are demonstrated in thin‐film coatings due to a combination of optical interference and light scattering effects. These vivid colors are concealed under ambient illumination but can be observed when light is reflected from the film surface. The origin of the effect is explored computationally and it is shown that, in thin‐films of lossless dielectrics coated on near‐perfect conductors, incident electromagnetic waves form standing waves. Electric field intensities at the thin film interfaces are maximized for wavelengths that fulfil destructive interference conditions, while nanoscale roughness can enhance scattering at these boundaries. The interplay of these two factors yields vivid, thickness‐dependent colors. This approach increases the repertoire of optical effects and perceived colors in thin coatings. When combined with traditional thin‐film interference colours, dichromatic images with distinctly changing colors can be generated, which can function as a covert, optical security feature.

中文翻译：

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通过光散射发现隐藏的结构颜色

由于光学干涉和光散射效应的结合，在薄膜涂料中显示出异常的结构颜色。这些鲜艳的色彩在环境照明下被隐藏起来，但是当光从胶片表面反射时可以观察到。通过计算探索了效应的起源，结果表明，在接近完美导体上涂覆的无损电介质薄膜中，入射电磁波形成驻波。对于满足破坏性干涉条件的波长，薄膜界面处的电场强度最大，而纳米级粗糙度可以增强这些边界处的散射。这两个因素的相互作用产生了鲜艳的，取决于厚度的颜色。这种方法增加了薄涂层中的光学效果和可察觉的颜色。