Fabrication of Optical Non-Circular Lenses by a Laser Ion-Exchange Method and Its Analysis.

Abstract

The growing use of optical lenses in optical integrated circuits has necessitated finding a better, more cost-effective way of producing them. We have succeeded in developing a method of producing high-quality micro lenses on soda-lime grass plates by combining laser annealing and ion-exchange; The method is referred to as a “Laser Ion-Exchange Method”. The use of this technique makes it increase the refractive indexes on both sides of a soda-lime glass plate to create an optical lens. The upper surface of the glass is annealed by CO₂ laser beam irradiation while the underside is subjected to ion-exchange between Na⁺ of the glass and K⁺ of KNO₃ of an immersion bath. This method was applied to producing circular, non-circular, linear and array micro-lenses.