Patent ID: 8259530

Claim:
A system for analyzing material around a borehole, the system comprising: a tool configured and sized to be positionable within the borehole and comprising: a transducer configured and arranged to generate a first acoustic wave at a first frequency and a second acoustic wave at a second frequency; a non-linear material arranged to receive the first and second waves, wherein, in operation, the first and second acoustic waves pass through the non-linear material and a composition of the non-linear material produces a collimated beam by mixing of the first and second acoustic waves, such that the collimated beam has a frequency equal to a difference of the frequencies of the first and the second acoustic waves, and wherein the collimated beam has a frequency of at least 20 kHz; a steering device arranged to controllably direct the collimated beam away from the borehole into the material around the borehole; one or more receivers arranged to receive the collimated beam after it has reflected or backscattered from an inhomogeneity in the material around the borehole; and a processor in communication with a memory having machine executable instructions stored therein which, when executed cause the processor to analyze the collimated beam after it has reflected or backscattered from an inhomogeneity in the material around the borehole to generate an image of the material.