权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Development of an X-ray Spectrometer with Sub-Micron Spatial Resolution

亚微米空间分辨率 X 射线光谱仪的研制

基本信息

批准号：
12440075
负责人：
DOTANI Tadayasu
金额：
$ 4.93万
依托单位：
Institute of Space and Astronautical Science
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2000
资助国家：
日本
起止时间：
2000 至 2002
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-12440075/
关键词：
X-ray CCD Spectrometer X-ray detector FPGA 画像処理データ処理

项目摘要

We have studied methods to improve the spatial resolution of the X-ray CCD detector as a spectrometer. The spatial resolution of X-ray CCD is determined mainly by (1) pixel size of the CCD, (2) noise of the measured pulse heights, and (3) data processing algorithm. Among these, we concentrated on items (2) and (3), because the development of CCD with small pixels is beyond the scope of current research.Both the clock signals and the analogue electronics are keys to reduce the noise of the pulse heights. We adjusted the phase of the clock signals and the sampling timing to minimize the interference of the clocking noise to the output. We developed a low-noise preamplifier and an active low-pass filter to improve the signal-to-noise ratio of the analogue circuits. With these modifications, we could reduce the measurement noise significantly. We also studied the best algorithm to determine the incident position of X-ray photons from the distribution of measured charges. We found that just a simple model fitting with a 2-dimensional Gauss function gives a good result.We could determine the incident position of X-ray photons with an accuracy of about 20% of the pixsel size. We estimate that the position error can be reduced to 10% with further improvement of S/N ratio. CCDs with pixel size smaller the 10 μm are now available for X-ray detection. With these CCDs it is possible to achieve a spatial resolution less than 1 μm. This is the goal of our research.

研究了提高X射线CCD探测器空间分辨率的方法。X射线CCD的空间分辨率主要取决于（1）CCD的像素尺寸，（2）测量脉冲高度的噪声，和（3）数据处理算法。其中，由于小像元CCD的发展超出了目前的研究范围，我们重点研究了（2）和（3）项，时钟信号和模拟电子学都是降低脉冲高度噪声的关键。通过调整时钟信号的相位和采样时序，减小了时钟噪声对输出的干扰。为了提高模拟电路的信噪比，我们研制了低噪声放大器和有源低通滤波器。通过这些修改，我们可以显着降低测量噪声。研究了由测量电荷分布确定X射线光子入射位置的最佳算法。我们发现用一个简单的模型拟合二维高斯函数就可以得到很好的结果，我们可以确定X射线光子的入射位置，精度约为像素尺寸的20%。我们估计，随着信噪比的进一步提高，定位误差可以减小到10%。像素尺寸小于10 μm的CCD现在可用于X射线检测。使用这些CCD，可以实现小于1 μm的空间分辨率。这是我们研究的目标。