PERFORMANCE ANALYSIS OF FIBER OPTIC SPECTROMETER

The multimode optical fiber can be used as a high resolution fiber optic based spectrometer (FOS). After calibration the wavelength dependent speckle patterns produced by interference between the guided modes of the fiber. A performance analysis of the effects of the fiber geometry and length on the spectral resolution and bandwidth, also the additional limitation on the bandwidth imposed by speckle contrast reduction when measuring dense spectra has been demonstrated. A laboratory model using multi-mode optical fiber was designed and implemented for the purpose of spectral analysis based on the recording of the speckle pattern emerging from the other side of the optical fiber. Different prepared concentrations of both Sucrose and NaCl solutions samples tested by different approaches, high resolution and broadband fiber based spectrometer systems. The beam distribution can be represented by the speckle pattern, which can be detected by using a CCD camera placed at the end of the multimode optical fiber. The results of this study demonstrate the advantage of using a multimode optical fiber based spectrometer.