DEFECT INSPECTION METHOD AND DEFECT INSPECTION DEVICE

• Main Authors: MATSUDA SHUNSUKE, KOBAYASHI SHINJI
• Format: Patent
• Language: English; Japanese
• Published: 08.08.2022
• Subjects: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIRCHEMICAL OR PHYSICAL PROPERTIES; MEASURING; PHYSICS; TESTING

To provide a defect inspection method and defect inspection device capable of detecting unevenness in optical properties of a linear polarizing plate in a case where an optical film formed by laminating a protective film and a release film on the linear polarizing plate, is used as a test object.SOLUTION: A defect inspection method of a linear polarizing plate uses an optical film including the linear polarizing plate as a test object. The optical film includes a release film, the linear polarizing plate, and a protective film in this order. The defect inspection method includes an arrangement step of arranging, along an optical axis, a first filter having a first polarizer, a first phase difference compensation plate, the optical film, a second phase difference compensation plate, and a second filter having a second polarizer in this order, and arranging the optical film in such a direction that the surface thereof in the release film side faces the phase difference compensation plate. The first phase difference compensation plate compensates birefringence of the release film, while the second phase difference compensation plate compensates birefringence of the protective film.SELECTED DRAWING: Figure 2 【課題】直線偏光板にプロテクトフィルムと剥離フィルムとが積層されている光学フィルムを被検査物とする場合において、直線偏光板の光学特性のムラを検出することができる欠陥検査方法及び欠陥検査装置を提供する。【解決手段】直線偏光板を有する光学フィルムを被検査物とする、前記直線偏光板の欠陥検査方法であって、前記光学フィルムは、剥離フィルムと、前記直線偏光板と、プロテクトフィルムと、をこの順に有し、前記欠陥検査方法は、光軸に沿って、第１偏光子を有する第１フィルタ、第１位相差補償板、前記光学フィルム、第２位相差補償板、及び第２偏光子を有する第２フィルタ、をこの順で、かつ、前記光学フィルムを、前記剥離フィルム側の表面が前記位相差補償板に対向する向きで配置する配置工程を有し、前記第１位相差補償板は前記剥離フィルムが有する複屈折を補償し、前記第２位相差補償板は前記プロテクトフィルムが有する複屈折を補償する。【選択図】図２