X-ray tomography

X-ray tomography, also called X-ray computed tomography or XCT, is an imaging method used to look inside a PV module. It can be used to examine less obvious delaminations at higher resolution than visual inspection gives, including delaminations that cannot be seen by eye. Delamination means the bond between the glass, encapsulant, active layers and back layers has failed, and moisture ingress and corrosion often follow it. Like ultrasonic scanning, X-ray tomography takes more time per examination than quicker methods such as visual inspection or thermography. It covers only a small physical area, so optical profilometry is better for measuring cracks across large areas of backsheet.

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• sentence 1: support check: partial - Passages give XCT = X-Ray Computed Tomography and mention X-ray tomography examining delaminations, but nothing explicitly says it is used to look inside a PV module (imaging method) generally.
• sentence 4: support check: partial - Passage says X-ray tomography and ultrasonic scanner both require greater examination time, but only relative to unspecified methods; visual inspection and thermography are not explicitly named as quicker comparators. -->