Research on mechanism and control technology of fixed pattern noise between multi-fibers of microchannel plate

As an excellent two-dimensional electron multiplier device for transmission and enhancement of electronic image, microchannel plate (MCP) has the advantages of small volume, light weight, high resolution, high gain, low noise, low operating voltage, which plays an irreplaceable role in the fields of low-light-level night vision, space detection, nuclear detection, ultraviolet warning, medical image and so on. In recent years, with the continuous expansion of the application fields and the improvement of related manufacturing technologies, the performance requirements of MCP, especially the image quality, are getting higher and higher. 4G standard is the latest international requirements of image intensifier with FOM (Figure of Merit) reached more than 1800. Fixed pattern noise between multi-fibers of MCP is a common image defect. This defect not only increases the noise, reduces the signal-to-noise ratio, but also greatly interferes with the imaging quality, which has become a bottleneck problem restricting the improvement of FOM. This research is focused on the formation mechanism and control technology of fixed pattern noise between multi-fibers of MCP. The result shows that the formation mechanism of the fixed pattern noise between the multi-fibers is caused by the difference in microchannel structure, which leads to the difference in secondary electron yields between adjacent multi-fibers. Improving microchannel uniformity is an effective way to eliminate fixed pattern noise. The difference in microchannel structure is caused by the diameter deviation during fiber drawing. Through analysis and experimental measurement, it is found that the "heating-constant-cooling" zone of the drawing furnace has an optimal structure.