Parallel detection of amplitude-modulated, ultrasound-modulated optical signals
نویسندگان
چکیده
منابع مشابه
Parallel detection of amplitude-modulated, ultrasound-modulated optical signals.
We investigated the effect of amplitude-modulated (AM) ultrasound (US) on acousto-optic (AO) signals. A phantom was exposed to both AM US and a green laser, and CCD measurements of speckle contrast were made with various exposure times. The results show that the AO signal oscillates at the AM frequency when the CCD exposure time is a fraction of the AM period and stops oscillating when the CCD ...
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We demonstrate that microscopic imaging is feasible in ultrasound-modulated optical tomography (UOT) of soft biological tissues, using a high-frequency focused ultrasound transducer with a 75-MHz central frequency. Our experiments in tissue mimicking phantoms show that at an imaging depth of about 2 mm, an axial resolution better than 30 microm can be achieved, whereas the lateral resolution is...
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We describe a generalization of traditional coherence that estimates the relationship between frequency components of one or two signals at different frequencies. The key idea of this technique is to apply amplitude modulation to one of the signals prior to a traditional coherence analysis. The modulated coherence includes traditional coherence as a special case. This is useful for identifying ...
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ژورنال
عنوان ژورنال: Optics Letters
سال: 2010
ISSN: 0146-9592,1539-4794
DOI: 10.1364/ol.35.002633