DOUBLE REFRACTION MEASURING INSTRUMENT AND DOUBLE REFRACTION MEASURING METHOD

摘要

PROBLEM TO BE SOLVED: To accurately calculate retardation Rth in a thickness direction on-line in a film manufacturing process for continuously feeding a sheetlike film to manufacture a film.;SOLUTION: The polarization characteristics of the film are measured from the normal line direction of the film by a first polarization characteristic measuring part 11 and the orientation axis azimuth of a sample 16 is calculated on the basis of the measuring result by an axis/retardation calculation means 61. An in-plane azimuth control means 64 performs the azimuth revolution of a second polarization characteristic measuring part 17 so that the oblique incident light of the second polarization characteristic measuring part 17 becomes parallel to the calculated orientation axis azimuth. The sample 16 is fed by a feed roll 21, and the reagent measured by the first polarization characteristic measuring part 11 reaches the measuring position of the polarization characteristic measuring part 17, when measurement is started by the second polarization characteristic measuring part 17. The axis/retardation calculation means 61 calculates the retardation Rth in the thickness direction of the film on the basis of the measuring results of the first and second polarization characteristic measuring parts 11 and 17.;COPYRIGHT: (C)2010,JPO&INPIT