Abstract: An interferometer includes a resonant cavity having a movable mirror and at least one fiber optic component acting as a fixed mirror. A surface of the fiber optic component is coated with a reflective film. An actuator is coupled to the movable mirror, such that when a scattered optical beam is coupled to the cavity, interference occurs between the surface of the fiber optic component coated with reflective film and a surface of the movable mirror facing the surface of the fiber optic component coated with reflective film. The reflective film on the surface of the fiber optic component causes closely spaced spectral lines within the scattered optical beam to be suitably resolved.

Abstract: A method of Raman detection for a portable, integrated spectrometer instrument includes directing Raman scattered photons by a sample to an avalanche photodiode (APD), the APD configured to generate an output signal responsive to the intensity of the Raman scattered photons incident thereon. The output signal of the APD is amplified and passed through a discriminator so as to reject at least one or more of amplifier noise and dark noise. A number of discrete output pulses within a set operational range of the discriminator is counted so as to determine a number of photons detected by the APD.

Abstract: A photonic crystal based collection probe is provided. The probe includes a photonic crystal configured to guide and condition a beam of Raman scattered photons. Further, the device includes a spectrograph in optical communication with the photonic crystal and configured to receive Raman scattering from the photonic crystal. The device may be employed in a Raman spectrometer system.