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一、空隙技术对一个放射诊断医生来说,在投照中他很关心如何减少到达底片的散射线.因为,这种到达底片的散射线不仅不能提供诊断信息,实际上反而使X射线象的细节变得模糊,降低了有价值的诊断信息量.我们知道,由散射X射线引起的曝光可使底片发灰,俗称灰雾.为了减少灰雾,通常采用滤线栅,滤线栅对提高X射线的象质有很大的作用.然而,采用滤线栅拍X线片也存在一些不足之处:1)使用静止滤线栅,不可避免地会在底片上留下铅条阴影,有碍图象的完整性;2)诚然,采用活动滤线栅,可以消除底片上的铅条阴影,但无论是哪种滤线栅,都不可能完全滤去散射线.譬如说,出现在与铅条相平行的面上的一部分散射线,就能通过铅条
First, the gap technology For a diagnostic radiologist, in the projection he is concerned about how to reduce the scattering line to reach the film, because the scattering line to reach the film not only can not provide diagnostic information, but in fact make X-ray The details become blurred, reducing the amount of valuable diagnostic information.We know that exposure caused by scattered X-rays can make the film gray, commonly known as fog.In order to reduce the fog, usually using the grid, the grid to improve X-ray image quality has a great effect.However, there are some drawbacks when using the grid to pat the X-ray film: 1) The use of a stationary grid will inevitably leave a lead shadow on the film, with 2) It is true that the use of active grids eliminates the shadow of lead on the negatives, but it is impossible to completely remove the scattered rays regardless of the grids.For example, Part of the plane parallel to the surface of the scattering line, you can lead through