An integrated spectrometer instrument, including an optical source formed on a chip, the optical source configured to generate an incident optical beam upon a sample to be measured. Collection optics formed on the chip are configured to receive a scattered optical beam from the sample, and filtering optics formed on the chip are configured to remove elastically scattered light from the scattered optical beam at a wavelength corresponding to the optical source. A tunable filter formed on the chip is configured to pass selected wavelengths of the scattered optical beam, and a photo detector device formed on the chip is configured to generate an output signal corresponding to the intensity of photons passed through the tunable filter.