Abstract:
PURPOSE:A long-standing conundrum is why photoacoustic tomography (PAT) possesses the unique ability to produce images devoid of speckle artifacts while all other coherent imaging technologies do not. METHODS:In this paper, we explain the inherent mechanism that suppresses speckle in PAT, and the analysis was validated by simulations based on an experimental PAT system. RESULTS:We found that the speckle-free feature of PAT results directly from the optical absorption contrast. CONCLUSIONS:All optical absorbers expand on laser excitation, and therefore all initial photoacoustic pressure rises are positive, which engenders strong correlations among the photoacoustic waves from the absorbers. As a result, prominent boundaries always build up in photoacoustic images and suppress the interior speckle.
journal_name
Med Physjournal_title
Medical physicsauthors
Guo Z,Li L,Wang LVdoi
10.1118/1.3187231subject
Has Abstractpub_date
2009-09-01 00:00:00pages
4084-8issue
9eissn
0094-2405issn
2473-4209journal_volume
36pub_type
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