An Imaging Enhancement Method for a Terahertz Rotation Mirror Imaging System Based on a Scale-Recurrent Network

The terahertz (THz) rotation mirror imaging system is an alternative to the THz array imaging system. A THz rotation mirror imaging system costs less than a THz array imaging system, while the imaging speed of a THz rotation mirror imaging system is much higher than the imaging speed of a THz raster-scan imaging system under the same hardware conditions. However, there is some distortion in the THz image from the THz rotation mirror imaging system. The distortion, which makes images from the THz rotation mirror imaging system difficult to identify, results from the imaging principle of the THz rotation mirror imaging system. In this article, a method based on the scale-recurrent network (SRN) is put in place to correct the distortion. A comparison between distorted THz images and corrected images shows that the proposed method significantly increases the structural similarity between the THz images and the samples.

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Microwave Imaging of Breast Skin Utilizing Elliptical UWB Antenna and Reverse Problems Algorithm

Micromachines ◽

10.3390/mi12060647 ◽

2021 ◽

Vol 12 (6) ◽

pp. 647

Author(s):

Sameer Alani ◽

Zahriladha Zakaria ◽

Tale Saeidi ◽

Asmala Ahmad ◽

Muhammad Ali Imran ◽

...

Keyword(s):

Skin Cancer ◽

Imaging System ◽

Signal Transmission ◽

Similarity Index ◽

Structural Similarity ◽

Microwave Imaging ◽

Ultra Wideband ◽

Uwb Antenna ◽

System A ◽

High Structural Similarity

Skin cancer is one of the most widespread and fast growing of all kinds of cancer since it affects the human body easily due to exposure to the Sun’s rays. Microwave imaging has shown better outcomes with higher resolution, faster processing time, mobility, and less cutter and artifact effects. A miniaturized elliptical ultra-wideband (UWB) antenna and its semi-spherical array arrangement were used for signal transmission and reception from the defected locations in the breast skin. Several conditions such as various arrays of three, six, and nine antenna elements, smaller tumor, multi-tumors, and skin on a larger breast sample of 30 cm were considered. To assess the ability of the system, a breast shape container with a diameter of 130 mm and height of 60 mm was 3D printed and then filled with fabricated skin and breast fat to perform the experimental investigation. An improved modified time-reversal algorithm (IMTR) was used to recreate 2D images of tumors with the smallest radius of 1.75 mm in any location within the breast skin. The reconstructed images using both simulated and experimental data verified that the system can be a reliable imaging system for skin cancer diagnosis having a high structural similarity index and resolution.

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High-Resolution Speckle-Free Ultrasound Imaging System-A Potential Solution for Detecting Missed Breast Cancer

10.21236/ada398166 ◽

2001 ◽

Author(s):

Matthew T. Freedman

Keyword(s):

Breast Cancer ◽

High Resolution ◽

Ultrasound Imaging ◽

Imaging System ◽

Potential Solution ◽

System A

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Modeling and image quality enhancement for dynamic compressive imaging system

Journal of Algorithms & Computational Technology ◽

10.1177/17483026211008098 ◽

2021 ◽

Vol 15 ◽

pp. 174830262110080

Author(s):

Changjun Zha* ◽

Qian Zhang* ◽

Huimin Duan

Keyword(s):

Image Quality ◽

Imaging System ◽

Quality Enhancement ◽

Target Image ◽

Compressive Imaging ◽

Image Quality Enhancement ◽

System A ◽

Single Column ◽

The Impact

Traditional single-pixel imaging systems are aimed mainly at relatively static or slowly changing targets. When there is relative motion between the imaging system and the target, sizable deviations between the measurement values and the real values can occur and result in poor image quality of the reconstructed target. To solve this problem, a novel dynamic compressive imaging system is proposed. In this system, a single-column digital micro-mirror device is used to modulate the target image, and the compressive measurement values are obtained for each column of the image. Based on analysis of the measurement values, a new recovery model of dynamic compressive imaging is given. Differing from traditional reconstruction results, the measurement values of any column of vectors in the target image can be used to reconstruct the vectors of two adjacent columns at the same time. Contingent upon characteristics of the results, a method of image quality enhancement based on an overlapping average algorithm is proposed. Simulation experiments and analysis show that the proposed dynamic compressive imaging can effectively reconstruct the target image; and that when the moving speed of the system changes within a certain range, the system reconstructs a better original image. The system overcomes the impact of dynamically changing speeds, and affords significantly better performance than traditional compressive imaging.

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One-shot BRDF imaging system to obtain surface properties

Optical Review ◽

10.1007/s10043-021-00689-x ◽

2021 ◽

Author(s):

Hiroshi Ohno ◽

Takahiro Kamikawa

Keyword(s):

Surface Properties ◽

Imaging System ◽

Reconstruction Method ◽

Surface Reflectance ◽

Bidirectional Reflectance Distribution Function ◽

Bidirectional Reflectance ◽

Color Mapping ◽

System A ◽

Cone Surface ◽

Bidirectional Reflectance Distribution

AbstractThe bidirectional reflectance distribution function (BRDF) that describes an angle-resolved distribution of surface reflectance is available for characterizing surface properties of a material. A one-shot BRDF imaging system can capture an in-plane color mapping of light direction extracted from a surface BRDF distribution. A surface roughness identification method is then proposed here using the imaging system. A difference between surface properties of a matt paper and a glossy paper is experimentally shown to be detected using the method. A surface reconstruction method of an axisymmetric micro-object using the imaging system is also proposed here. The imaging system experimentally shows that it can reconstruct an axisymmetric aluminium cone surface with a height of 37 μm.

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