Patent ID: 11860106
Assignee: SANGUIS CORPORATION
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 11:
12. A method of obtaining high gain stimulated Raman spectroscopy comprising:
providing a first continuous wave laser having first output beam at a tunable optical frequency which is modulated at a first RF modulation frequency (f1) and a first average power of laser radiation;
providing a second continuous wave laser having a second output beam at an optical frequency which is modulated at a second RF modulation frequency (f2) and a second average power of laser radiation, wherein the first and second RF modulation frequencies (f1, f2) are selected such that their difference or sum beat notes (f1−f2; f1+f2) represent a Raman resonance frequency;
rasterizing the first and second output beams continuous wave lasers by scanning the first and second output beams onto a sample over an exposure area, wherein the scanned sample exposure area is exposed to an average power of laser radiation that is reduced relative to first and second average powers of laser radiation and in response thereto is stimulated by the laser beams to emit Raman radiation signals;
receiving the Raman signals at first and second photosensors; and
delivering output of the first and second photosensors to a differential amplifier that is configured to provide sensitivity and gain to signals at the beat note resonant frequency (f1−f2) and to filter out signals at other frequencies so as to output the Raman radiation signals with gain.