The name is absent

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32 × 32 image of a rather complicated object with only 300 measurements (~30%),
but it still relies on mechanical moving parts. A fast spatial THz modulator for the
binary modulation of the THz beam is required to realize a high-speed single-pixel
CS THz imaging system.

Therefore, two spatial THz modulators are designed and implemented based on
metamaterial split-ring resonators. The first-generation THz SLM design, a 4-by-4
pixel array, demonstrates a modulation depth of 35% to 50% at the resonant fre-
quency, uniformly across all pixels, and a negligible amount of crosstalk among pix-
els. Demonstrated by the interference patterns with a double slit configuration, the
kHz-rate operation of this spatial modulator can allow fast switching of random pat-
terns for the single-pixel imaging system. The metamaterial spatial THz modulator
operates under small voltage levels at room temperature and with low power con-
sumption.

The second-generation design of the THz SLM has a much larger number of pixels
(32×32) than the first-generation design. In order to independently control the 1024
SLM pixels, we build a control circuit system with a FPGA and voltage amplifying
components. This system allows synchronization between the SLM control signals
and the Т-ray acquisition system. Initial THz experiments find only 20% modulation
depth at each pixel of the second-generation THz SLM, and discover some fabrication
and packaging defects on the THz SLM samples. Further investigation is needed to
explain the low modulation depth, and to improve the fabrication and packaging
procedures.

The major contributions of this thesis are the demonstration of the single-pixel
THz imaging system, and the implementation and characterization of the THz SLM.
When properly fabricated and packaged in the future, the second-generation THz

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