| 摘要 |
PURPOSE:To detect the position of the picture plane of films of any coloring accurately by disposing plural photodetectors provided with filters of different colors in plural detecting optical paths disposed in the different positions for a film passage. CONSTITUTION:An illuminating lamp 10 and heat-shield glass 11 are disposed above a passage Y for a film X, and a mask 12 and a slit 13 are provided below the same. A blue filter 4, a green filter 15 and a red filter 16 are disposed in the width direction below the slit, and are so constituted that the rays past these filters 14-16 are made incident to photodetectors 20-22 through optical fiber bundles 17-19. Therefore, the position of the picture plane of films of any coloring is detected accurately. |
