We present a field-portable lens-free optical tomographic microscope, which enables sectional-imaging of a large sample volume (~20 mm) with an axial-resolution of <7 μm. This platform, weighing ~110 grams, employs cost-effective lightemitting diodes and an optoelectronic sensor array to record in-line projection holograms of objects placed on a sensor-chip along different directions of illumin...

Most of commercial computed tomography (CT) system employs filtered back projection (FBP) based algorithm to reconstruct tomographic image. Although FBP originated from an analytical solution, it generates streak artifacts during practical implementation due to interpolation between projection lines. The presence of streak artifacts will result in misinterpretation of tomographic features espec...

introduction: filtering can greatly affect the quality of clinical images. determining the best filter and the proper degree of smoothing can help to ensure the most accurate diagnosis. methods: forty five patient’s data aquired during brain phantom spect studies were reconstructed using filtered back-projection technique. the ramp, shepp-logan, cosine, hamming, hanning, butterworth, metz and w...

Introduction: Measurement of the complex 3D radiation dose distribution created with advanced radiotherapy techniques such as IMRT and SRS became very important. Polymer gel dosimetry (PGD) is proposed method to recording this dose distribution. MRI, X-ray CT, ultrasound, spectrophotometry and optical CT scanners can be used for readout of Polymer gel dosimeters. Although MRI i...

We perform a parametric study of the newly developed time-of-flight (TOF) image reconstruction algorithm, proposed for real-time imaging in total-body Jagiellonian PET (J-PET) scanners. The asymmetric 3D filtering kernel is applied at each most likely position electron-positron annihilation, estimated from emissions back-to-back γ-photons. optimisation its parameters studied using Monte Carlo s...

SPECT images are observation data acquired by a gamma-camera following an orbit around the patient’s body, at regularly spaced angles. A reconstructed image is the discrete representation of a slice or cross-section of the isotope distribution within the patient, transversal to the gamma-camera rotation axis. Bayesian reconstruction methods have been extensively used to reconstruct medical imag...

This paper reports on the local reconstruction of a region-of-interest from 3D terahertz imaging data obtained via a quantum cascade laser (QCL). It is an important step in understanding the trade-off between wavelet based techniques and traditional filtered back projection (FBP) for local reconstruction of terahertz images. The advantage of local reconstruction is a reduction in measurement ti...

Image reconstruction is an important task in X-ray computed tomography. In this paper we discuss the results of morphological analysis of test objects in high-noise conditions and compare image reconstruction using two widely employed methods in computed tomography, namely Filtered Back Projection and Algebraic Reconstruction Technique. In our test tomography experiments, we used a laboratory X...