[OPTICAL REVIEW Vol. 6, No. 1 (1999) 88-92]

Development of a Unique, High Precision Linear Motor Integrated Air Slide Table, and Its Application to Laser Beam Writers

Hajime ONDA

Mechatronics R&D Center, NTN Corporation, 1578, Higashikaizuka, Iwata, Shizuoka, 438-8510 Japan

(Received May 29, 1998; Accepted October 29, 1998)

This paper reports on the development of a unique, high precision linear motor integrated air slide table for precise positioning and its application to laser beam writers for photo-mask pattern-making. The air slide table takes advantage of the balance between the air bearing's levitating and magnetic forces. A brushless linear motor and a high resolution linear encoder are integrated into the table. The unique construction of the device results in a very compact package with excellent accuracy. The basic characteristics of the air slide table are evaluated. The device is applied to a laser beam writer, which must be capable of rendering minute and precise patterns for photo-masking equipment. Examples are given including optical devices such as wave guides and Fresnel zone plates which were fabricated and evaluated. Experimental data is given to show that the Fresnel zone plate fabricated here can be used to focus a laser beam to the theoretical limit, just like a standard refractive lens.

Key words : linear motor, air slide table, patterning, precise positioning, diffractive optical element, laser writer