A study of novel mid-infrared optical devices: Wave plates and tunable filters

Mid-Infrared;Wave Plate;Birefringence;Filter;Subwavelength grating;Plasmons

Taylor, Andrew ; Wasserman ; Daniel M.

关键词: Mid-Infrared;    Wave Plate;    Birefringence;    Filter;    Subwavelength grating;    Plasmons;   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/44174/Andrew_Taylor.pdf?sequence=1&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

The mid-infrared wavelength range is important for both molecular sensing and thermal imaging. However, many optical devices that are common in the visible range are not as accessible in the mid-infrared. In this thesis, we look to partially address this problem by proposing two novel structures using subwavelength gratings. First, we look at a wave plate design that uses a physical path length difference to impose aphase shift between the components of incident light as an alternative to costly birefringent crystals. Then, we look at a crossed grating structure that serves as a narrowband filter due to its extraordinary transmission. We also propose a way to make the filter structure actively tunable.