GB1345642A - Raman spectrometer - Google Patents

Abstract

1345642 Spectrometer NIHON DENSHI K K 20 March 1972 [18 March 1971] 13023/72 Heading G1A [Also in Divisions G2 and H1] In a Raman spectrometer comprising a laser light source and means within the laser or external thereof for changing in a scanning manner the wavelength of the test beam. Raman light is selected according to its wavelength by a Fabry-Perot interferometer and applied to a detector for recording as a spectrum. Raman light from a sample 8 Fig.1 irradiated by the output from a dye laser 1 is applied to a detector 15 which may be a photo-multiplier, by way of lens 10, interference filter 11, and two Fabry-Perot interferometers 12, 13, the arrangement giving a single sharp peak output as described with reference to Fig.2 (not shown). The laser may contain Rodamin 6G, and the wavelength is scanned by rotating a prism 5 or in an alternative embodiment a grating, the wavelength being monitored in a second path 18-21. In an alternative laser arrangement Fig. 6, YAG crystals 41 containing doped Nd ions is irradiated by a lamp 42, and the arrangement includes a second harmonic generator 43 for wavelength doubling, and an ultra-sonic Q switching mechanism 47 to generate high amplitude, pulsed laser light. The wavelength is scanned by varying the temperature of a crystal 51 in a parametric oscillator through which the beam is passed. In a further modification the Raman light path includes a Fabry-Perot interferometer and a monochromator.