Until recently, the construction of polarizers for operation below approximately 260 nm were limited to materials such as magnesium fluoride and crystalline quartz. These materials have a much smaller birefringence than calcite, but unlike calcite they have good transmission below 200 nm. These materials are, however, not well suited for Glan-Taylor-type polarizer designs, as they do not produce a large angular separation of the polarized components. A new material, a-barium borate, has recently become available, which transmits to just below 200 nm and has a birefringence that approaches that of calcite. We analyze the performance of various polarizer designs that use this material. Results are presented that compare theory with experimental investigation of a manufactured device.

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A scanning optical profilometer is described which can simultaneously and independently measure the differential phase/amplitude variation of light reflected off an object surface. This information may then be interpreted as topographical and reflectivity variation of the object surface. The system is based on a heterodyne interferometer and uses two beams to probe the surface. The theoretical sensitivity of the system is 3×10−3 mrad in phase and 3 in 105 in reflectivity variation, both measured in a 1 kHz bandwidth. Preliminary measurements of film thickness and reflectivity variation are presented. This system also has potential applications for imaging objects with minute structural variations.

The design and construction of an optical instrument is described to enable accurate and reliable resonance Raman scattering and photoluminescence measurements to be acquired in the 200–700 nm (1.77–6.2 eV) wave band, with minimum user intervention between changes of the excitation wavelength. An f/6 line or point focus is formed at the sample. f/2 achromatic catadioptric optics image the scattered light to the entrance slit of an f/7.5 spectrometer. An ultraviolet sensitive charge coupled device camera enables imaging and alignment of samples within the excitation laser region, providing an imaging resolution of better than 13 μm (results presented elsewhere suggest a resolution limit of 7 μm). The use of an aperture plate allows pseudo-confocal operation, leading to considerable improvement in depth discrimination when interrogating extended volume scatterers. This mode of operation furthermore eliminates stray light derived from the Rayleigh line, thereby enabling line focus spectra to be obtained to very low wave numbers. The optics present a unique method of interrogating a sample with an extended lateral and well-defined axial interaction region with a high collection efficiency (optical throughput of >41%), simultaneously offering broadband achromatic spectral response in collection from 200 to 700 nm.

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