Newton fringe

Newton Fringe. A rainbow effect in films that have been metallized under high vacuum, caused usually by inadequate thickness of the top lacquer. 

Schematic representation of an apparatus for the determination of mechanical film stresses by observing Newton fringes between a stressed circular substrate disk and an optical flat [149].

FIGURE 26.7 Newton s interference fringes and the corresponding contour diagrams showing the difference between the contact area of a ruhher sphere and a glass plate when (right) wetted with distilled water and (left) with a polar substance added to the water. (From Roherts, A.D., The Physics of Tire Traction, Theory and Experiment, Hayes, D.L. and Browne, A.L. (eds.). Plenum Press, New York/London, 1974.)... 

Although Newton studied adhesion of glass lenses shortly after Galileo s death, noting ye apparition of a black spot at ye contact of two convex glasses [2], and measuring the interference fringes which indicated very close contact of the... 

If a convex lens touches a perfect flat plate, at a favorable ratio of the lens curvature radius, light wavelength and the presence of an optical magnifying system, so-called Newton s rings can be observed. They represent the fringes of equal thickness in the form of concentric circles. 

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