Universiti Teknologi Malaysia Institutional Repository

Precision manufacture of spherical and aspheric surfaces on plastics, glass, silicon and germanium

Venkatesh, Vasisht, C. (2003) Precision manufacture of spherical and aspheric surfaces on plastics, glass, silicon and germanium. Current Sciences, 84 (9). pp. 1211-1219.

Full text not available from this repository.

Abstract

This paper discusses the manufacture of aspheric and spherical surfaces in industries as well as in the universities with which the author is associated. Surfaces on plastics are produced by replicating them on glass moulds which, in turn, are replicated using ceramic moulds (for rotationally non-symmetrical lenses) or (for rotationally symmetrical lenses) ground on appropriate aspheric generators. The ceramic mould surfaces are generated on CNC milling machines. Rotationally symmetrical glass lenses were generated on both 4-axis and 5-axis CNC machining centres using both metal-bonded as well as resinoid-bonded cup grinding wheels. The same techniques were used for making lenses out of thermal imaging materials (silicon and germanium) where attempts to get semi-ductile mode of grinding were highly successful. The manufacture of spherical silicon lenses in industry is highlighted especially with respect to non-ductile regime grinding that increases polishing time. Results of surface texture and profile accuracy analyses using the Form Talysurf instrument are presented together with SEM pictures of the surfaces.

Item Type:Article
Subjects:T Technology > TJ Mechanical engineering and machinery
Divisions:Mechanical Engineering
ID Code:7389
Deposited By: Maznira Sylvia Azra Mansor
Deposited On:01 Jan 2009 07:20
Last Modified:01 Jan 2009 07:20

Repository Staff Only: item control page