Abstract: A coherent anti-Stokes Raman spectroscopy (CARS) method and apparatus for producing a broadband CARS vibrational spectrum of a sample in a single picosecond laser pulse. A laser pulse having a picosecond duration and a frequency of .omega. is directed into a liquid cell containing D.sub.2 O which generates a picosecond continuum pulse having a broad range of frequencies .omega..sub.WL and a picosecond duration. A second harmonic of the laser pulse is produced to form a probe pulse having a frequency of .omega..sub.1 and a picosecond duration. The probe pulse and the continuum pulse are spatially and temporally combined and the combined pulses are directed into a sample to excite the Raman active vibrational resonances in the sample. In response the sample emits a beam of radiation which contains an anti-Stokes spectrum of energy characteristic of the sample. The anti-Stokes spectrum is separated from the beam of radiation for detection and analysis.

Abstract: Improvements in Praseodymium solid state YLF lasers operating in the blueeen spectral region at room temperature and providing short pulses useful for underwater communication and detection systems. A dye laser with a narrow spectral output matched to the absorption spectra of the solid state laser is provided as a laser pump. The Pr doped YLF crystal of the solid state laser is physically oriented so it can be longitudinally pumped by light polarized parallel to the c-axis of the crystal, and the solid state laser is equipped with special spectrally selective mirrors. The foregoing and other modifications of prior Pr solid state laser systems provide increased efficiency and power output.