Abstract: A compact ellipsometric apparatus is constructed using as a building block a tri-beam ellipsometric sensor having a monochromatic source of polarized light with a diverging beam of sufficient divergence that three analyzers and associated light detectors may be placed into the beam side by side so that they each receive light reflected from a surface under study at the same angle of reflection. Pairs of these sensors are used together, with one of each pair having in the optical path a quarter wave plate matched to the monochromatic light wavelength and the other of the pair having no quarter wave plate, but with the light wavelength and angle of incidence being the same for each pair. A variety of measurements are made by constructing apparatus using one or more pairs of these basic sensors, the pairs of sensors varying from each other in the light wavelength of the source and the angle of incidence of the polarized beam of light to the surface.

Abstract: An instrument for monitoring the surface characteristics of materials, whereby the surface is characterized by measurement of a current of photo-emitted electrons flowing from the surface to a collector on the instrument. The instrument directs ultra violet light against the surface being measured, and the photoelectrons emitted are characteristic of surface features such as oxide thickness, contamination, or fatigue. The current of electrons emitted from the surface is compared with previously established limits for surface quality to provide an acceptability test of the surface. The instrument is portable and does not require the use of a vacuum chamber.

Abstract: A hand-holdable apparatus for testing, and a method of testing, a light-reflective surface for contamination. The apparatus and the method are based upon a novel "off null" ellipsometry technique by the use of which contamination of the surface is ascertained, if the intensity of light reflected by the surface being tested exceeds a predetermined threshold of intensity.

Abstract: Ellipsometric parameters for a given structural member surface area are obtained by scanning the structural member surface area at an oblique angle with a polarized monochromatic light beam and receiving the reflected light beam with a rotating analyzer. The rotating analyzer outputs are detected at its 0.degree., 45.degree. and 90.degree. azimuth orientations by a photodetector. The photodetector outputs can be plotted in their proper relationship to the scanned surface area boundaries to provide maps useful in nondestructive testing and other applications. Equations are provided that permit the conversion of the photodetector outputs into ellipsometric physical parameter values for refractive index, absorption coefficient and material thickness. Scanning in one embodiment is accomplished by a structural member holding device that can be simultaneously rotated and vertically translated.

Abstract: A miniaturized ellipsometric testing device having a laser for precisely impinging a prescribed beam of light upon a surface to be tested and a detector for capturing the reflected impinged beam only within prescribed limits. The value of the reflected impinged beam, which is transmissible to the detector, is used in determination of the validity of the surface tested; the miniaturized device is couplable to the laser light source and the detector by fiber optic cables.