| 摘要 |
According to one aspect, the invention relates to a device for detecting a resonant nonlinear optical signal of Stimulated Raman Scattering type (SRS) induced in a sample. The device comprises electro-optical means for causing the interaction, in the sample, at a first modulation frequency, of trains of light pulses (14, 12) of angular frequencies ω1 and ω2 and, at a second modulation frequency, trains of light pulses (12, 16) of angular frequencies ω2 and ω3, such that ω2 - ω1 = ω3 - ω2 = &OHgr;R where &OHgr;R is an angular frequency of molecular vibrational resonance of the sample. The device furthermore comprises means of synchronous detection (70, 80) at the first and second modulation frequencies of nonlinear optical signals resulting from the interaction of the light pulses in the sample and means of electronic processing (80) making it possible on the basis of electronic signals resulting from the synchronous detection to obtain a signal characteristic of the molecular vibrational resonance of the sample. |
