The ultraviolet (UV) absorption spectra of several gasoline samples are measured using a compact static Fourier-transform (FT) spectrometer. The FT-UV spectrometer is constructed from crystalline quartz Wollaston prisms and polarizers fabricated from beta barium borate to form an interferogram in the spatial domain. The interferogram is recorded with a UV-sensitive detector array and Fourier transformed to yield spectra. Investigation using principal component analysis enables the identification of important gasoline properties such as origin.

A fiber-coupled, compact laser wavemeter based on a modified Wollaston prism has been constructed and evaluated. The path difference between orthogonal polarization states of the input light varies smoothly across the aperture of the prism forming an interferogram in the spatial domain that is recorded with a CCD detector array. A Fourier transform of this interferogram gives the spectral distribution of the incident light. Alternatively, for a narrow-linewidth source a fringe period measurement technique is used to obtain precision measurement of the center wavelength. Using 752 interferogram data points we obtain a wavelength precision of 1 part in 10(6). The elimination of moving parts from the design makes the recorded interferogram inherently stable.

The development of a novel static Fourier-transform spectrometer based on two Wollaston prisms, two polarizers, and a compact two-dimensional detector array is described. The wavelength calibration is fixed by the geometry of the prisms and the detector array and is therefore inherently stable. The Wollaston prisms are fabricated from materials with opposite sign of birefringence which gives a significantly increased field of view compared with existing Wollaston prism based Fourier-transform spectrometers. The spectrometer operates in the visible region of the spectrum, has a resolution of 350 cm−1, an aperture of 6×4.6 mm, and a field of view of ±10°. The optical assembly is interfaced to a laptop computer resulting in a rugged, portable instrument with no moving parts.

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