| 摘要 |
PROBLEM TO BE SOLVED: To make inspectable a flaw of a web by using transmitted light and reflected light at the same position. SOLUTION: The web inspecting apparatus is provided with a laser beam projecting means 30 for projecting laser beam with a predetermined wavelength, a scanning means 21 for scanning a web 3 laterally by laser beam by reflecting laser beam, a reflected beam receiving means for receiving the beam reflected from the web, and/or a transmitted beam receiving means for receiving beam transmitted through the web 3. Further, a region 12 becoming flat in the lateral direction of the web 3 over the length equal to or more than the diameter of scanning beam toward the feed direction of the web 3 is provided on the feed route of the web 3, and scanning beam is projected on this region.
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