| 摘要 |
PURPOSE:To improve an after image characteristic of a pickup tube remarkably even if the illuminance of surface of the tube is low, by illuminating an output fluorescent plane of an X-ray picture conversion tube with radiant rays etc. capable of exciting the fluorescent plane. CONSTITUTION:X-rays from an X-ray source 1 are made incident on an X-ray incident plane 4 of an X-ray picture conversion tube 3 via a body 2 to be inspected. An output fluorescent plane 5 of the tube 3 is picked up with a pickup lens 7, a pickup tube 8 and a pickup plane 9. In this case, the output fluorescent plane 5 is illuminated with a wavelength light in a photosensing region of the tube 8 in the optical reflection zone of the fluorescent body, or the radiant rays capable of exciting the fluorescent substance from a bias light source 6. Thus, the pickup device is operated with the increased optical signal level at the region where the after image of the luminous amount versus after image characteristic of the pickup tube is reduced. Further, since the illuminated light is observed brighter with the reflection from the fluorescent plane, allowing to obtain the bias illumination effect. |
