Dual Wavelength Raman Source permits SERDS Spectroscopy Technique in the Lab

Laser Components is pleased to introduce the LabSource series of bench top laser sources manufactured by PD-LD Inc, with Volume Bragg Grating® stabilised laser diodes. Two models are available; the LS-1 with a single Volume Bragg Grating® stabilised laser diode, and the LS-2 featuring two stabilised sources. Wavelength stability is +/- 5pm over 8 hours with a +/-0.5% power stability over the same period. The dual wavelength functionality of the LS-2 enables use in a variety of unique tasks including Shifted Excitation Raman Differential Spectroscopy (SERDS). The technique involves two Raman spectra formed from closely matching but different excitation wavelengths allowing the offset of background fluorescence. The result is a dramatic improvement in the identification and measurement of organic and biological samples and in security industries where fluorescence is widespread, previously unachievable with traditional single-source Raman spectroscopy. The modules are customisable principally in terms of the laser diode power and wavelength. Standard wavelengths include 647nm, 785nm, 830nm and 1064nm, however, as long as the laser diode is available and with a wavelength between 405nm and 2.2μm, a VBG can created to stabilise that wavelength. Both the LS-1 and LS-2 include integrated drive circuitry for ACC and APC modes with adjustment resolutions of 1mA and 5mW respectively and software allow integration with existing laboratory instruments with a user friendly interface. The LS-2 model has been designed particularly for the SERDS techniques outlined in PD-LDs most recent US patent 7,982,869 and represents a significant development in the capabilities of Raman spectroscopy.