High resolution photoacoustic system based on acoustic lens and photoacoustic sensors array
Jianning Han1, Tingdun Wen2, Peng Yang1, Lu Zhang1
COMPUTER MODELLING & NEW TECHNOLOGIES 2014 18(4) 289-295
1School of Information and Communication Engineering, North University of China, 3 Xue Yuan Road, Taiyuan, China
2Key Laboratory of Electronic Testing Technology, North University of China, 3 Xue Yuan Road, Taiyuan, China
Photoacoustic tomography is a nondestructive bio-photonic imaging method based on the differences of optical absorption within biological organization. An approach using the lens with negative refractive index and photoacoustic sensors array to make the evanescent wave involved in the imaging process was presented in this paper. A set of comparative experiments was demonstrated on the imaging effect between the ordinary lens and the lens designed in this work. The experiment showed that the imaging effect of photoacoustic tomography by the designed lens had greatly outperformed the ordinary lens. In order to illustrate the good results, according to the characteristics of ultrasonic waves produced in photoacoustic effect, the propagation properties of the acoustic waves in lens with different refractive index was discussed. On the basis of analysing evanescent decay of ordinary acoustic lens which results in the loss of high-frequency information with image details in current photo-acoustic tomography system, the diffraction limit of was broken through and the image resolution was greatly improved by the lens with negative refractive index in theory.