• Journal of Biomedical Engineering Research
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• v.21 no.4
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• pp.419-431
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• 2000

In this paper, a new beamforming technique is proposed, which can completely eliminate all the artifacts caused by digital scan converter. In the proposed method, named display-pixel-based focusing(DPBF) by the authors, ultrasound waves are focused directly at the display pixels instead of sampling points on the polar coordinate. Consequently. the DPBF system does not require the digital scan converter. To verify the proposed method, we modified a commercial scanner and performed experiments with a 3.5 MHz convex array and a 7.5 MHz linear array. We also defined and measured ICRA/B(Image Coarseness Ratio) to compare the image quality quantitatively. The experimental results with in vivo and in vitro data show that the proposed method improves the ICRA/B considerably, resulting in much smoother and finer images.