Prism right-angle

The analysing prism is first placed at right angles to the polarising prism, so that the field appears green the analyser is then rotated through 90°, the field then appearing red with a violet shade. 

The thin film sensors were deposited on 20 mm right angle prisms for characterization. The test apparatus was sealed to protect the film from the surrounding air and to expose the films to predetermined gas mixtures, as shown in Figure 1. The sensors consisted of three layers 40 nm gold, 600 nm W03 and 3 nm palladium. Figure 2 shows a set of spectra... 

Tetragonal Two equal axes and one longer, all at right angles to each other Prism, pyramid Vesuvian, rutile, chalcopyrite... 

Monoclinic Three unequal axes one angle not 90 degrees, two at right angles Prism Gypsum, orthoclase, mica... 

Triclinic Three unequal axes, no right angles prism Microcline, albite... 

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