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Patent Searching and Data


Title:
PROJECTION OPTICAL APPARATUS
Document Type and Number:
Japanese Patent JPH0629179
Kind Code:
A
Abstract:

PURPOSE: To always expose a photosensitive board under accurate imaging characteristics even when a so-called a multiple oblique illuminating method and an ordinary illuminating method are switched to be used.

CONSTITUTION: A main controller 50 maintains imaging characteristics of a projection optical system PI, in a constant state through a driving element control unit 53 based on a prediction control arithmetic parameter. A correction error of the characteristics is corrected while measuring the characteristics of the system PL by using a pattern plate 15, etc., at a predetermined time interval in a transient period in the case of varying illumination conditions, and the parameter is corrected after influence of the illumination conditions of previous time is eliminated.


Inventors:
Taniguchi, Tetsuo
Application Number:
JP1992000203075
Publication Date:
February 04, 1994
Filing Date:
July 07, 1992
Export Citation:
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Assignee:
NIKON CORP
International Classes:
G03F7/20; H01L21/027; H01L21/30; (IPC1-7): H01L21/027; G03F7/20
Attorney, Agent or Firm:
大森 聡