Wavefront shaping assisted design and application of effective diffractive optical elements providing spectral splitting and solar concentration: splicons

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2020-9
Gün, Berk Nezir
The diffractive optical elements that mainly concentrate light are primarily designed via numerical methods. These methods incur increased computational time as well as a lack of real-life conditions. Our experimental approach offers a new design method for SpliCon, a particular type of diffractive optical element that can spectrally split and concentrate broadband light (420 nm - 875 nm). We managed to form a programmable SpliCon by wavefront shaping via a phase-only spatial light modulator.The method we adopted is ∼ 300 times faster than the conventional methods. We spectrally split the broadband range into three frequency bands, as well as achieving simultaneous concentration of the incident light. The spatial light modulator steered the frequency bands of red (560 nm - 875 nm), green (425 nm - 620 nm), and blue (420 nm - 535 nm) into two and three regions. When we have two concentration regions, the total enhancement factor is 715 %; and the spectral splitting ratios are 52 %, 57 %, and 66 % for the red, the green, and the blue channels, respectively.For the three concentration region case, the total enhancement factor is 564 %; and the spectral splitting ratios are 43 %, 37 %, and 34 % for the red, the green, and the v blue channels, respectively. Additionally, we present the methods to convert a programmable SpliCon into a physical Splicon that can be fabricated at large scale and low cost

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Citation Formats
B. N. Gün, “Wavefront shaping assisted design and application of effective diffractive optical elements providing spectral splitting and solar concentration: splicons,” M.S. - Master of Science, Middle East Technical University, 2020.