INSPECTION METHOD

• Main Authors: MATSUDA SHUNSUKE, KOBAYASHI SHINJI
• Format: Patent
• Language: English; Japanese
• Published: 09.08.2023
• Subjects: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIRCHEMICAL OR PHYSICAL PROPERTIES; MEASURING; OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICS; PHYSICS; TESTING; TESTING STATIC OR DYNAMIC BALANCE OF MACHINES ORSTRUCTURES; TESTING STRUCTURES OR APPARATUS NOT OTHERWISE PROVIDED FOR

To provide an inspection method that is a reflection type inspection method and can easily determine whether there are defects on a circular polarizing plate.SOLUTION: An inspection method determines whether there are defects on a film-shaped inspection target 10 that includes a circular polarizing plate 1 in which a polarizing film 11 and a retardation film 14 are laminated, and a release film 16a which is laminated on the retardation film 14 side of the circular polarizing plate 1 and formed of a polyethylene terephthalate resin. A light source 4, a band-pass filter 2 which allows light having a predetermined wavelength to pass through, a first polarizing section 3A, an inspection target 10, and a second polarizing section 3B are disposed, and an angle θ of incidence of light onto the inspection target 10 is changed so as to minimize effects of the phase difference of the release film 16a. The method determines whether there are defects on the circular polarizing plate 1 by observing light reflected by the inspection target 10 from the second polarizing section 3B side.SELECTED DRAWING: Figure 1 【課題】反射型の検査方法であって、円偏光板の欠陥の有無を容易に判断することができる検査方法を提供すること。【解決手段】偏光フィルム１１と位相差膜１４とが積層されてなる円偏光板１、及び、円偏光板１の位相差膜１４側に積層されポリエチレンテレフタレート系樹脂からなる剥離フィルム１６ａを備えるフィルム状の被検査物１０の欠陥の有無を判断する検査方法である。光源４と、所定の波長の光を透過させるバンドパスフィルタ２と、第１の偏光部３Ａと、被検査物１０と、第２の偏光部３Ｂを配置し、剥離フィルム１６ａが有する位相差の影響が小さくなるように被検査物１０への光の入射角θを変化させる。被検査物１０によって反射された光を第２の偏光部３Ｂ側から観察して円偏光板１の欠陥の有無を判断する。【選択図】図１