| 摘要 |
<p>PURPOSE:To provide a method as well as a device for inexpensively marking a lamination plate without any need of a substantial facility by projecting polarized light to the plate containing information recorded via the change of crystal orientation at the specified position of a resin film, and transmitting the polarized light through a polarizing filter for detecting the distribution of the crystal orientation. CONSTITUTION:When a lamination raw plate 5 such as a steel sheet is heated with a roll and a resin film 3 is' compression pasted thereon, a pattern roll is employed for forming a portion having temperature different from surrounding temperature and the crystal orientation of the film 3 is thereby changed to mark a bar code, a position mark or the like thereon. A. lamination plate 4 so marked is, then, exposed to monochromatic light projected from a light source 6. The light from the source 6 turns into light L1 having a transverse vibration plane after a polarizing plate 1. Then, the light is incident on the film 3 and reflected with the plate 5. As a result, light having a vertical component is incident on a polarizing filter 2a. In this case, a part of the light pass the filter 2a. The light through the filter 2a is converted to the variable density of light at an image processing device, and a mark is read on a monitor 9.</p> |
