Optical performance of circular Fresnel spectrometer
Autor: | Uhn Lee, Sang H. Choi, Glen C. King, Yeon-Joon Park, Hyunjung Kim |
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Rok vydání: | 2011 |
Předmět: |
Physics
Spectrometer business.industry Fresnel zone antenna Astrophysics::Instrumentation and Methods for Astrophysics Physics::Optics Zone plate Fraunhofer diffraction law.invention symbols.namesake Optics law Blazed grating symbols Fresnel number Physics::Atomic Physics Arago spot business Fresnel diffraction |
Zdroj: | SPIE Proceedings. |
ISSN: | 0277-786X |
Popis: | Most of today's spectrometers are based on Fraunhofer diffraction with a periodic regular line grating. We demonstrate a new type of a spectrometer which is based on Fresnel diffraction that can be miniaturized smaller than Fraunhofer diffraction limit, a2/λ where a is the aperture size, and λ is the wavelength of the light. The theory, fabrication, and optical performance of the miniaturized Fresnel spectrometer with a circular Fresnel grating, i.e. zone-plate will be presented. The theoretical calculation shows that the spectral resolution of Fresnel spectrometer is not fundamentally determined by the size of the grating but it is determined by the total number of rings. The miniaturized Fresnel spectrometer has a circular grating of 750 micrometer diameter and the volume of the optical path between the grating and the aperture slit is only 1mm3. In spite of this small dimension, it achieved a spectral resolution of 22nm which is similar to the typical value of a color filter. |
Databáze: | OpenAIRE |
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