  A new method to correct the emulsion deformation, mainly produced in the
development process, is developed to recover the high accuracy of nuclear
emulsion as a tracking device. The method is based on a precise photomask and a
careful treatment of the emulsion films. A position measurement accuracy of 0.6
{\mu}m is obtained over an area of 5 cm x 7 cm. The method allows to measure
positions of track segments with submicron accuracy in an ECC brick with as few
as 10 reference tracks for alignment. Such a performance can be important for
hybrid emulsion experiments at underground laboratories where only a small
number of reference tracks for alignment are available.
