Patent ID: 8432543

Claim:
A laser system for analyzing or exposing a sample to optical radiation, the system comprising: a first light source producing monochromatic coherent pump light pulses having a duration in a picosecond range and a first wavelength ; a second light source producing monochromatic coherent Stokes light pulses having a duration in a picosecond range and a second wavelength energetically spaced from the first wavelength by a vibrational energy state of the sample and a Gaussian beam profile, wherein a difference of photon energy corresponding to the first wavelength and photon energy corresponding to the second wavelength populate the vibrational energy state of the sample; a third light source being phase-locked to the second laser and producing monochromatic coherent interfering light pulses having a duration in a picosecond range and a third wavelength energetically spaced from the second wavelength by a second vibrational energy state of the sample; a fourth light source producing coherent actinic light pulses having at least one fourth wavelength , wherein photon energy corresponding to the at least one fourth wavelength is substantially equal to an energy difference between the virtual energy state and a stable quantum state of the sample; and an optical assembly combining the light pulses from the first, second, third and fourth light sources into a pulsed overlapping light beam and focusing the overlapping light beam with a Gaussian beam profile for the pump, Stokes and actinic pulses and an annular beam profile for the interfering light pulses in a focal plane on or in the sample.