Patent ID: 7295325

Claim:
An apparatus for measuring characteristics of a sample, comprising: a first source supplying a pump pulse of radiation to a first surface area of the sample to cause a disturbance of the sample at the first surface area; a second source supplying a radiation probe pulse having a duration of less than about 1 picosecond for probing the sample at the first surface area, the probe pulse having a plurality of wavelength components in a bandwidth; a converter converting the probe pulse into a corresponding converted pulse of longer duration than duration of the probe pulse prior to conversion so that each temporal portion of the converted pulse corresponds to and comprises one of the wavelength components, and supplying the converted pulse to the sample at the first surface area; a detector detecting changes in characteristics of the sample at wavelengths of the wavelength components corresponding to temporal portions of the converted pulse after the converted pulse has been modified by the sample and providing an output, wherein at least some of the temporal portions have been affected by the disturbance; and a device analyzing the output of the detector or a signal derived therefrom to determine characteristics of the sample.