Title:
METHOD FOR CORRECTING MEASUREMENT ERROR OF LENGTH MEASURING DEVICE
Document Type and Number:
Japanese Patent JPH05332726
Kind Code:
A
Abstract:
PURPOSE:To provide a method for correcting the measurement error of a length measuring device capable of correcting the waviness of a mirror to make precise measurement without requiring the precise assembly and adjustment of the mirror. CONSTITUTION:A sample 30 having patterns 30P1-30Pn is placed on a table 8, and the coordinates of a number of positions of the pattern 30p is measured. The sample 30 is then rotated at 180 deg. around the straight line parallel to the arranging direction of the patterns 30P1-30Pn (turned over), and the coordinates are similarly measured. Each measurement value contains the error by the waviness of mirrors 24X, 24Y and the manufacturing error of the sample 30, but the latter is in the relation of (+) and (-) in both the measurements. Therefore, by adding both the measurement values followed by multiplication by 1/2, the error portion of waviness of the mirrors 24X, 24Y can be taken out, and this is used as a correction value.
Inventors:
HOSHINO YOSHIHIRO
NAGASAWA KIYOSHI
NAGASAWA KIYOSHI
Application Number:
JP13885992A
Publication Date:
December 14, 1993
Filing Date:
May 29, 1992
Export Citation:
Assignee:
HITACHI CONSTRUCTION MACHINERY
International Classes:
G01B11/02; G01J1/00; (IPC1-7): G01B11/02
Attorney, Agent or Firm:
Kenjiro Take (1 person outside)
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