A multivariate optical computing and analysis system includes a light source configured to radiate a first light along a first ray path; a modulator disposed in the first ray path, the modulator configured to modulate the first light to a desired frequency; a spectral element disposed proximate the modulator, the spectral element configured to filter the first light for a spectral range of interest of a sample; a cavity disposed in communication with the spectral element, the cavity configured to direct the first light in a direction of the sample; a tube disposed proximate the cavity, the tube configured to receive and direct a second light generated by a reflection of the first light from the sample, the tube being further configured to separate the first and second lights; a beamsplitter configured to split the second light into a first beam and a second beam; an optical filter mechanism disposed to receive the first beam, the optical filter mechanism configured to optically filter data carried by the first beam into at least one orthogonal component of the first beam; and a detector mechanism in communication with the optical filter mechanism to measure a property of the orthogonal component to measure the data.