| 摘要 |
PURPOSE: To obtain a method for non-destructively rapidly measuring alignment deviations of layers with a low cost by attaching a plurality of vernier scales to materials of the layers, then positioning them on a translucent main reference unit attached with the scales, and reading the superposed scales. CONSTITUTION: After a plurality of vernier scales 13 are attached to a substance layer 1 used for a multilayer printed circuit board, and the layer 1 is positioned on a translucent main reference unit 10 attached with the scales 13. The superposed scales 13 are read with respect to the unit 10, and hence an alignment deviation of the layer 1 is measured. For example, one set of positioning pins 12 are provided, the layer 1 of a copper-clad glass epoxy board provided at four corners with the scales 13 is aligned on the unit 10 disposed at corners of an upper surface of a glass plate 11 with perpendicularly crossed sets of the scales 13. The unit 10 is illuminated from its lower surface, and the superposed scales 13 are read. |
