Acoustic imaging probe incorporating photoacoustic excitation

Abstract

Various embodiments of the present invention provide for a photoacoustic imaging probe for use in a photoacoustic imaging system, whereby the probe is comprised of a cohesive composite, acoustic lens incorporating aspheric geometry and exhibiting low or practically no measurable dispersion of acoustic waves constructed of at least one material with a low acoustic impedance and attenuation and a relatively low acoustic velocity and at least one other material with a low acoustic impedance and attenuation and a relatively high acoustic velocity. The probe is housed in a conduit filled with a low acoustic velocity and low acoustic impedance fluid such as water or mineral oil. The lens may be designed as a telecentric lens, an acoustic zoom lens, a catadioptric lens, or a reflective lens. The lens focuses acoustic waves on an acoustic imager which detects the image. The acoustic imager may be designed as a 2 dimensional array of transducers. Research to date indicates that within the range of acoustic frequencies of interest, 1 MHz-50 MHz and preferable 2 MHz-10 MHz, there exists little velocity variation within the materials of interest, and the lens design approach may currently be considered to be essentially monochromatic. The acoustic waves can be generated when an emitting light source illuminates a test subject comprising materials that generate acoustic waves at differing intensities and/or frequencies when illuminated with light, for example tissue containing blood vessels, wherein the blood vessels excite and generate an acoustic pulse. The probe has an acoustic window made of a material with low acoustic impedance which allows the acoustic pulse to enter the probe without distortion and then may be reflected by a mirror onto the acoustic lens. The probe may include the emitting light source and an optical window to allow light emitting from said light source to illuminate the test subject.

Dependencies are inferred from the claim text.