An infrared beam is directed to the surface of a Mylar mirror, and the mirror reflects that beam. The process segregates the removal of fluoride and fluorosilicate ions, from the totality of ions in the waste water stream, thus improving treatment efficiency and reducing costs. The image-forming chemistry i) and ii) components are in reactive association and uniformly dispersed or dissolved within a binder in one or more layers of the element. When one of these control signals is applied to the delay line, it is applied to half the elements, either the odd or the even numbered elements.