Fabrication of small complex-shaped optics by plasma chemical vaporization machining with a microelectrode.
We have developed plasma chemical vaporization machining by using a microelectrode for the fabrication of small complex-shaped optical surfaces. In this method, a 0.5 mm diameter pipe microelectrode, from which processing gas is drawn in, generates a small localized plasma that is scanned over a workpiece under numerical computer control to shape a desired surface. A 12 mm x 12 mm nonaxisymmetric mirror with a maximum depth of approximately 3 microm was successfully fabricated with a peak-to-valley shape accuracy of 0.04 microm in an area excluding the edges of the mirror. The average surface roughness was 0.58 nm, which is smooth enough for optical use.
Takino
Hideo
H
Nikon Corporation, Kanagawa, Japan. takino@nikongw.nikon.co.jp
Shibata
Norio
N
Itoh
Hiroshi
H
Kobayashi
Teruki
T
Nemoto
Koshichi
K
Fujii
Takashi
T
Goto
Naohiko
N
Yamamura
Kazuya
K
Sano
Yasuhisa
Y
Mori
Yuzo
Y