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•Terahertz(THz) radiation is nonionizing is therefore harmless to live organisms, as opposed to higher energy radiation, such as x-rays and UV rays. THz low scattering characteristic, as compared to optical rays, and strong absorption by water makes THz useful for imaging organic tissue. • In a Lumpectomy procedure, a tumor is removed from a predetermined area. In most cases, a surgeon will often remove a larger amount of tissue to ensure that all of the cancer is removed however this can extend the patient's recovery period and it does not guarantee that all the cancerous tissue was removed.. • Using the THz Jets Transmission (Tx) Imaging method the goal will be to allow a surgeon to better assess the margins of the excised tissue using higher THz resolution images. • This method is done by transmitting a THz signal through a Teflon sphere, then through the sample, and finally to the receiver on the other side. • Teflon spheres have the ability to filter out the lower terahertz frequencies which then have the potential to produce high-resolution images.
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Ptychographic X-ray speckle tracking with multi-layer Laue lens systems
The ever-increasing brightness of synchrotron radiation sources demands improved X-ray optics to utilize their capability for imaging and probing biological cells, nano-devices and functional matter on the nanometre scale with chemical sensitivity. Hard X-rays are ideal for high-resolution imaging and spectroscopic applications owing to their short wavelength, high penetrating power and chemical sensitivity. The penetrating power that makes X-rays useful for imaging also makes focusing them technologically challenging. Recent developments in layer deposition techniques have enabled the fabrication of a series of highly focusing X-ray lenses, known as wedged multi-layer Laue lenses. Improvements to the lens design and fabrication technique demand an accurate, robust,in situand at-wavelength characterization method. To this end, a modified form of the speckle tracking wavefront metrology method has been developed. The ptychographic X-ray speckle tracking method is capable of operating with highly divergent wavefields. A useful by-product of this method is that it also provides high-resolution and aberration-free projection images of extended specimens. Three separate experiments using this method are reported, where the ray path angles have been resolved to within 4 nrad with an imaging resolution of 45 nm (full period). This method does not require a high degree of coherence, making it suitable for laboratory-based X-ray sources. Likewise, it is robust to errors in the registered sample positions, making it suitable for X-ray free-electron laser facilities, where beam-pointing fluctuations can be problematic for wavefront metrology.
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- Award ID(s):
- 1231306
- PAR ID:
- 10587755
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- Journal of Applied Crystallography
- Date Published:
- Journal Name:
- Journal of Applied Crystallography
- Volume:
- 53
- Issue:
- 4
- ISSN:
- 1600-5767
- Page Range / eLocation ID:
- 927 to 936
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1107/s1600576720006925
