Refraction problems in continuous wave THz-CT

Guo Fenglei; Zhang Mingyue; Xiao Zheng; Li Xiangjun; Liu Jianjun

Terahertz CT setup was designed and constructed by backward wave Oscillator which has been used to perform computed tomography of 3D objects. However, the imaging quality is affected by strong refraction from materials with the refractive index greater than 1.5 in objects. At first, the cross section image of a teflon modal was reconstructed from the projection dataset by the filtered backprojection algorithm , then high refraction effects were analyzed. Finally, a human tooth sample was scanned and the cross section images were reconstructed to reveal its internal structures. However, the accuracy and resolution of the images were still limited owing to the high refraction effects. And the terahertz transmission depth in teeth was seriously affected by the thickness of enamel. The results in paper are helpful to improve the imaging quality of THz-CT and promote its applications especially in biomedical imaging of human bones like human tooth.

1. College of Information Engineering,Center for THz Research,China Jiliang University,Hangzhou 310018,China;

2. Naval Convalescent District,Hangzhou Sanatorium of Nanjing Military Command,Hangzhou 310002,China

Received Date: 2014-07-05

Rev Recd Date: 2014-08-15

Key words:

Abstract: Terahertz CT setup was designed and constructed by backward wave Oscillator which has been used to perform computed tomography of 3D objects. However, the imaging quality is affected by strong refraction from materials with the refractive index greater than 1.5 in objects. At first, the cross section image of a teflon modal was reconstructed from the projection dataset by the filtered backprojection algorithm , then high refraction effects were analyzed. Finally, a human tooth sample was scanned and the cross section images were reconstructed to reveal its internal structures. However, the accuracy and resolution of the images were still limited owing to the high refraction effects. And the terahertz transmission depth in teeth was seriously affected by the thickness of enamel. The results in paper are helpful to improve the imaging quality of THz-CT and promote its applications especially in biomedical imaging of human bones like human tooth.

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Reference (17)

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Refraction problems in continuous wave THz-CT

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