The name is absent

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Chapter 6

A future CS terahertz imaging system

6.1 Summary of results

In order to improve the image acquisition speed upon traditional raster-scanning
systems, this thesis demonstrates two novel terahertz imaging systems based on com-
pressive sensing: the CS Fourier THz imaging system and the single-pixel CS THz
imaging system.

The CS Fourier THz imaging system successfully recovers the test object with pixel
size 1.4 mm, using only a random subset of about 12% of the 4096 (64×64) uniform
Fourier samples scanned at the focal plane of a lens. This image reconstruction result
implies a 2/3 reduction of acquisition time compared to traditional raster scanning,
with a slight loss in imaging resolution, if the system scans the receiver along a
random path across a subset of pixels. The system also demonstrates successful
image reconstruction with only the Fourier amplitude using compressive sensing phase
retrieval. This setup could be useful for quality control applications, such as detection
of point impurities in manufactured products, because Fourier-domain measurements
are particularly sensitive to sharp point-like features.

While mechanical scanning of the receiver still limits the acquisition speed of the
CS Fourier imaging system, the single-pixel CS THz imaging system does not rely
on raster scanning, or a source∕detector array; instead, it uses random patterns for
imaging. Based on the theory of CS, the prototype system is capable of recovering a

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