| 摘要 |
<P>PROBLEM TO BE SOLVED: To precisely detect the cavity trouble or crack trouble of the surface of an ink receiving layer even in high glossiness ink jet recording paper with a surface glossiness of 75° or above. <P>SOLUTION: A halogen lamp is used as the light source of a light projector 28 for emitting detection light while a solid-state imaging element is used as a light receiver 30 for receiving reflected light, and a light projecting angle θ1 and a light receiving angle θ2 are set so as to become a regular reflecting condition of a range of 25-35°. By this constitution, the cavity trouble (b) or crack trouble (c) of the surface (a) of the ink receiving layer of the ink jet recording paper 14A can be detected precisely. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
