New Fabrication Process of Deep Paraboloidal Mirror by Combination of Elid-grinding and Electro-forming Techniques for Laman Spectroscopy Instrument

Abstract

In this paper, ELID grinding and electro-forming techniques were applied to fabricate a deep concave paraboloidal mirror which will be used in Laman spectroscopy instrument. First, an injection mold with paraboloid was fabricated by ELID grinding and polishing. After the injection mold was ground by a #4000 metal resin bonded diamond grinding wheel, Ra, Rz and Ry were 8nm, 36nm and 60nm respectively. In order to further reduce the surface roughness, the injection mold was polished by diamond paste with average grit size of 0.25 μ m. Half an hour later, the surface roughness was Ra2nm, Rzl5nm and Ry32nm. Secondly, the injection mold was used to electro-form the deep concave paraboloidal mirror.