| 摘要 |
<p>A method for characterizing a sample (930) is described. The method includes applying a first pulse of electromagnetic radiation (1012) to the surface of the sample (930) and thus creating a propagating strain pulse within the sample (930). A second pulse of second electromagnetic radiation (1015) is applied to the surface of the sample (930) so as to intercept the propagating strain pulse. The first and second pulses are applied through a structure, such as a reflector, (933) that is disposed over the surface of the sample (930) at a distance predetermined to form an optical cavity (50); the cavity (50) having a width related to a wavelength of the second electromagnetic radiation (1015). The method includes detecting at least one optical property of a reflection of the second pulse from the sample (930). The detected optical property(ies) of the reflection are associated with a characteristic of the sample. An, apparatus, computer-readable medium and structure (933) are also described.</p> |
