Three-Dimensional Nondestructive “Sampling” of Art Objects Using Acoustic Microscopy and Time–Frequency Analysis

The microsampling destructions, which are caused by the sampling procedures of analytical spectroscopic methods, are, in most cases, not permitted to art objects, which are extremely valuable, rare, and fragile. Consequently, the development of nondestructive analysis techniques becomes a necessity. In this paper, we present a technique and method for the nondestructive identification of the stratigraphic structure of the paint layers of art objects. Using acoustic microscopy, in combination with time-frequency representations, the continuous or discrete wavelet transform, or the Hilbert-Huang transform, the depth profile of the stratigraphy is determined.