Experimental characterization of fiber coupled NIR-AOTF for wavelength tuning

摘要

Acousto-Optical Tunable Filter (AOTF) based spectrophotometers are suitable for wide range of non-in-vasive and real-time spectroscopic measurements in various process industries and scientific applications. Integrating such a spectrophotometer from scratch, mandates understanding of the functionality of each sub-unit, namely Radio Frequency (RF) driver, AOTF and InGaAs detector by experimentally studying its operational characteristics. Comparison of RF driver characteristics provided in the datasheet and its experimental observations were elucidated. Possible test cases for controlling the wavelength tuning in a fiber pigtailed AOTF were explored by varying the modulation signal parameters applied to the RF driver and the corresponding inferences were reported. Such experimental understanding will aid in estimating the reliability of the complete spectrophotometer.