Resonance-Domain Diffractive Infrared Spectrometer

Abstract

Diffractive spectroscopy has served as one of the most powerful tools in the history of physics and extends its applications to optics, astronomy, and biology. However, diffractive spectroscopy suffers from its low efficiency compared to all the newly invented spectroscopic techniques in the past century. Resonance domain designs help to improve the efficiency of existing diffractive elements. Furthermore, based on the effective grating theory, the resonance-domain diffractive lens allows both focusing and dispersion within a diffractive component.In this thesis, the author studied the effective grating theory in the resonance domain and applied this approach to design, fabricate, and simulate a resonance-domain diffractive infrared spectrometer that operates in mid-infrared from 3µm to 5µm. The designed infrared spectrometer consists of a resonance domain diffractive lens and a single mid-infrared detector. This system achieved a stimulated efficiency of over 99%. The compact, broadband, and highly efficient spectrometer shows great promise for more extensive applications such as environmental monitoring, security screening, and biomedical research.