Presented Results and the Model

On the basis of reflection and structural analyses of the silver mirror and other different metal surfaces, it can be concluded that the light from flat parts of surface is mirror reflected light. The diffuse reflection arises from the parts of the surface between the flat parts of surface. Flence, these parts of a surface scatter light. 

Reflection analysis of a silver mirror surface taken as a reference standard showed that the reflection of light from this surface is mostly mirror reflection and that the degrees of mirror reflection are very close to the ideal reflectance of silver. The structural characteristics of this surface, which provide a high degree of mirror reflection, are flat and mutually parallel parts which are smooth on the atomic level, with adjacent flat parts being separated by several atomic diameters of silver. 

the conditions which must be fulfilled in order for metal surfaces to be mirror bright are (i) flat parts of the surface which are smooth on the atomic level and (ii) distances between adjacent flat parts are comparable with the distances between the adjacent flat parts of a silver mirror. 

The variety of results presented can be illustrated by a simple model which treats brightness from the point of view of geometrical optics only.12 The proposed model will be valid if the following assumptions are fulfilled  

In total, the brightness of a surface is determined by the ratio of flat parts to the surface between adjacent flat parts. Increasing the distance between adjacent flat parts leads to a decreasing brightness of the surface.12 

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