Popis: |
Large bandwidth acousto-optical spectrometers have now reached a very high level of maturity. They achieve very compatible results in comparison with other spectrometer types like filterbanks, autocorrelators, and chirp transform spectrometers. In addition, AOS are rather simple in design, have little complexity and can be designed for space applications very easily. A new generation of broad-band AOS, the array-AOS, consists of four parallel 1 GHz spectrometers built into one optical unit. Tests results in the laboratory as well at a radio-observatory are very promising. For example, the Allan variance minimum time has been found above 1000 seconds. In comparison it can be shown that the AOS spectra are less affected by instrumental noise or baseline distortions due to platforming effects as they are visible with most hybrid autocorrelators. For future applications of acousto-optics the development of cross-correlators seems to be feasible. First steps in this new direction are on the way.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only. |