Adaptation of a commercial Raman spectrometer for multiline and broadband laser operation

A commercial single laser line Raman spectrometer is modified to accommodate multiline and tunable dye lasers, thus combining the high sensitivity of such single monochromator systems with broadband operation. Such instruments rely on high-throughput interference filters that perform both beam alignment and Rayleigh filtering. Our set-up handles this dual task with two independent elements: a beam splitter and a long pass filter. Filter rotation shifts the transmission passband, effectively expanding the range of operation. Operation is demonstrated on single-walled carbon nanotubes, for which the set-up was optimized. As the set-up operates with standard optical elements it can be customized for specific needs with relative ease.