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电子探针的X射线图能以微米尺度显示元素在二维方向上的分布,这是人们所熟悉的。它是利用电子束在试样表面扫描,然后搜集自试样发射出的X射线光子,经放大后加到显象管成象。荧光屏上每个小亮点代表一个X射线光子,小亮点密集程度的不同反映了元素含量上的差别。但是,这种图象缺乏具体数量概念,小亮点的多少不仅与含量有关,还受实验条件和拍照时暴光长短的影响,而且它的灵敏度比较差,很难显示低含量和含量的微小变化。尤其是,它无法显示较大范围内元素的分布,这是因为放大倍数低于400倍时,电子束扫描范围的直径大于0.25mm,使得计数管、分光晶体和试样上的X射线源三者不在一个罗
It is well-known that the electron probe’s x-ray pattern shows the distribution of elements in two dimensions in the micron scale. It is the use of electron beam scanning the surface of the specimen, and then collected from the sample emitted X-ray photons, amplified by the imaging tube imaging. Each small bright spot on the screen represents an X-ray photon, and the difference in the intensity of small bright spots reflects the difference in elemental content. However, this image lacks a specific quantity concept. The number of small bright spots is not only related to the content, but also affected by experimental conditions and the exposure to light during photographing. Moreover, its sensitivity is poor and it is difficult to show small changes in content and content. In particular, it fails to show the distribution of elements over a larger area because the diameter of the electron beam scanning range is greater than 0.25 mm at magnifications lower than 400, so that the counting tube, the spectroscopic crystal, and the X-ray source on the sample Who is not a Luo