Summary: | 碩士 === 國立交通大學 === 電子物理系所 === 96 === The thesis, about an application of the volume holographic optical elements (VHOE), describes how to apply the technique of the transmission volume hologram recording to fabricate the diffraction grating elements for a spectrometer. The purpose of the designment and the method to produce dispersive grating elements is in order to improve the resolution and the spectral response of the dispersive thin grating elements. According to “the coupled wave theory” suitable for volume holographic gratings and due to calculating, we find volume gratings easily possess higher resolution than ordinary thin gratings after recording. For the thin hologram, however, the multiple gratings can not to be recorded. Due to the diffraction features of the volume hologram, we can utilize the trick of multiplexing to record multiple gratings in a medium. Generally, the thin holographic grating used in the spectrometer was designed rotatably by the driving motor. If we record multiple gratings to the volume hologram, we can fix the incident angle to disperse any multicolor light source in some given spectral ranges without rotating the grating during reading out. We will set how to make this kind of gratings, including the angles of incidence we choose during recording, and what kinds of wavelength the medium can relate.
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