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arXiv · 2502.20686

Development of a Neutron Imager using CMOS Pixelated Sensor

Yoshio Kamiya·Hidetoshi Ohshita·Ryutaro Nishimura·Toshiya Muto·Shingo Mitsui·Tomohiro Seya·Izumi Umegaki·Yasuo Arai
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Abstract

We acquired an image of the Siemens Star Chart using the 10B-INTPIX4 CMOS pixelated imager at J-PARC MLF BL21 (NOVA). The image blurriness, characterized by a root mean square (rms) value of 17 um in the line spread function, corresponds to an rms beam divergence of 2.7 mrad. for the neutron beam. This is equivalent to the effective geometrical ratio (L/D ratio) of 370. The contrast of the image was analyzed as a function of structural scale of the chart, and based on this contrast, the modulation transfer function (MTF) of the imaging system was evaluated. The results indicate that the structure corresponding to the 50% cutoff is 12 line-space pairs per mm.

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Yoshio Kamiya, Hidetoshi Ohshita, Ryutaro Nishimura, Toshiya Muto, Shingo Mitsui, Tomohiro Seya, Izumi Umegaki, Yasuo Arai. 2025-02-28. Development of a Neutron Imager using CMOS Pixelated Sensor. https://doi.org/10.7566/jpscp.45.011024

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