Matched spectral filter based on reflection holograms for analyte identification

作者：Cao Liangcai; Gu Claire^*

来源：Applied Optics, 2009, 48(36): 6973-6979.

DOI：10.1364/AO.48.006973

• Analytes
• Angular accuracy
• Interference alignment
• Multiplexed grating
• Raman spectrometers
• Raman Spectrum
• Recording beams
• Reflection gratings
• Reflection hologram
• Reflection spectra
• Rhodamine 6G
• Spectral filters
• Spectral peak
• Volume holographic

A matched spectral filter set that provides automatic preliminary analyte identification is proposed and analyzed. Each matched spectral filter in the set containing the multiple spectral peaks corresponding to the Raman spectrum of a substance is capable of collecting the specified spectrum into the detector simultaneously. The filter set is implemented by multiplexed volume holographic reflection gratings. The fabrication of a matched spectral filter in an Fe : LiNbO3 crystal is demonstrated to match the Raman spectrum of the sample Rhodamine 6G (R6G). An interference alignment method is proposed and used in the fabrication to ensure that the multiplexed gratings are in the same direction at a high angular accuracy of 0:0025°. Diffused recording beams are used to control the bandwidth of the spectral peaks. The reflection spectrum of the filter is characterized using a modified Raman spectrometer. The result of the filter's reflection spectrum matches that of the sample R6G. A library of such matched spectral filters will facilitate a fast detection with a higher sensitivity and provide a capability for preliminary molecule identification.

• 出版日期2009
• 单位University of California at Santa Cruz