Formation of a refractive index distribution profile in glasses due to ion exchange

The paper studies the refractive indexes radial distribution for various samples and its dependence on the conditions of ion exchange in order to obtain large aperture self focusing elements with a n(r) distribution in the form of a hyperbolic secant or a parabola. The spatial distribution obtained for alumoborosilicogermanate glass immersed in molten NaNO /SUB s/ is shown. The authors show that processing of potassium glass in molten lithium nitrate can be used in making elements for integral optics, where smaller gradient layers are required