TESTER FOR HETERO-CRYSTAL IN UNIDIRECTIONAL COAGULATION AND TEST METHOD

摘要

PROBLEM TO BE SOLVED: To provide a tester for hetero-crystal in a unidirectional coagulation capable of detecting a fine hetero-crystalline area and a test method.SOLUTION: The tester for hetero-crystal in a unidirectional coagulation includes: an illumination part for illuminating a test object area in the unidirectional coagulation with light; an imaging part for imaging the test object area; an illumination direction change part configured to change a rotation angle φ in a light illumination direction having the test object area as the center in a projection of the light illumination direction to a second plane surface orthogonal to a first plane surface including the test object area, the illumination part and the imaging part; and a hetero-crystal identification part for identifying a hetero-crystalline area in the test object area on the basis of a plurality of pieces of image data having a different rotation angle φ acquired by the imaging part.SELECTED DRAWING: Figure 1