Abstract: This invention relates to methods of forming interference anti-reflective, abrasion resistant and easy to clean coatings on plastic articles by improved microwave plasma modification to obtain a coating with stable layer thickness and a refractive index as low as 1.29-1.35, which is formed from organic silicon compounds.

Abstract: A method of designing progressive addition lenses is provided in which the surface of the lens is in effect synthesized directly from its specification. A desired pattern of grid lines is produced in which the astigmatism is distributed over the entire pattern of grid lines in a predetermined manner, a standard grid viewing system from which rays are traced is then assumed, and surface normals for each grid crossing are calculated by using the grid object and grid image as known quantities and solving for each surface normal using the law of refraction and determining the surface of the lens from the respective surface normals.

Abstract: A progressive addition lens is provided having a wide transition corridor and an improved balance between astigmatism and distortion in the field of peripheral vision to provide a wide, distortion-free clear view. This is achieved by employing a cosine function in blending the transition corridor with the peripheral area.