Abstract: A thermoacoustic imaging apparatus comprises an electromagnetic radiation source, an acoustic signal detection probe and a radiation responsive acoustic signal generator outside the sample area. The detection probe arrangement detects both signals generated in the sample area in response to the electromagnetic irradiation and an acoustic signal from the radiation responsive acoustic signal generator that has traveled through the sample area. An acoustic transmission parameter such as a speed of sound or absorption as a function of a position in the sample area is computed from signals due to the radiation responsive acoustic signal generator. The acoustic transmission parameter is used to correct the computation of a thermoacoustic image from detections due to acoustic signals generated in the sampled area.

Abstract: An apparatus includes first and second light sources for respectively generating broadband and monochromatic lights, a beamsplitter optically coupled to the first light source for splitting the broadband light into a reference light and a sample light, a reference arm optically coupled to the beamsplitter for receiving the reference light and returning the received reference light into the beamsplitter, a sample arm optically coupled to the beamsplitter and the second light source for combining the sample and monochromatic lights, delivering the combined light to the target of interest, collecting a backscattering light and a Raman scattering light generated from interaction of the combined light with the target of interest, returning the backscattering light into the beamsplitter so as to generate an interference signal between the returned backscattering light and the returned reference light in the beamsplitter, and directing the Raman scattering light in an output optical path.

Abstract: In one aspect of the present invention, an apparatus includes a first light source for generating a broadband light, and a second light source for generating a monochromatic light, a beamsplitter optically coupled to the first light source for receiving the broadband light and splitting the received broadband light into a reference light and a sample light, a reference arm optically coupled to the beamsplitter for receiving the reference light and returning the received reference light into the beamsplitter, and a sample arm optically coupled to the beamsplitter and the second light source for combining the sample light and the monochromatic light, delivering the combined sample and monochromatic light to the target of interest, collecting a backscattering light and a Raman scattering light that are generated from interaction of the sample light and the monochromatic light with the target of interest, respectively, returning the backscattering light into the beamsplitter so as to generate an interference sign

Abstract: A thermoacoustic imaging apparatus comprises an electromagnetic radiation source configured to irradiate a sample area and an acoustic signal detection probe arrangement for detecting acoustic signals. A radiation responsive acoustic signal generator is added outside the sample area. The detection probe arrangement detects both signals generated in a sample area in response to the irradiation and an acoustic signal from the radiation responsive acoustic signal generator that has traveled through the sample area. A computing system distinguishes first acoustic signal detections attributed to the acoustic signal generated by the radiation responsive acoustic signal generator and second acoustic signal detections attributed to the acoustic signals generated by the sample area. The computing system performs a tomographic computation of an acoustic transmission parameter as a function of a position in the sample area from the first acoustic signal detections.

Abstract: The invention relates to a method and system for determining a parameter representing an acoustic property of a material. The method comprises: generating an acoustic pressure wave in said material originating from a localized position; placing a plurality of acoustic receivers (6, 7) at mutually differing distances from the acoustic source (3); transforming a plurality of measured acoustic signals to represent field values in a common computational point; computing a signal representing a measure of overlap between said transformed plurality of acoustic signals as a function of said numerical estimates of said acoustic property parameter and deriving said acoustic property parameter from said overlap signal. Since the invention uses acoustic sources that are well localized in the material, the velocity calculations are simple and the geometry of the acoustic receivers in relation to the acoustic source can be exactly taken into account.