| 摘要 |
PURPOSE:To obtain the image of a part excellent in background brightness when the part is recognized through either a reflected illumination method or a transmitted illumination method. CONSTITUTION:When a CPU judges that a part 5 attracted by a suction nozzle 14 must be recognized through a transmitted illumination method, a liquid crystal layer 25 is turned transparent, and light is reflected by a white coating layer 24 to make a diffusion plate 22 bright. When a CPU judges that a reflected illumination method should be utilized, the liquid crystal layer 25 is put in a light shading state, and light is not reflected by the white coating layer 24 to turn the diffusion plate 22 dark. |
