针对半影孔加工和检测困难的缺点，设计了半影锥成像系统。根据神光Ⅲ主机装置中子产额条件，确定成像系统排布参数；根据点扩展函数的尖锐性和等晕性要求，确定半影锥参数；模拟半影锥系统的分辨率，以及在不同加工精度、偏心误差、旋转误差和物距误差时，对成像质量的影响。模拟结果表明，系统分辨率能达到15 μm，半影锥椭圆度的加工误差要小于0.1，瞄准的偏心误差要小于60 μm，旋转误差要控制在0.35 mrad以内，物距误差要控制在1 mm以内。

The aperture for neutron penumbral imaging is newly designed in order to reduce the difficulties of fabrication and detecting. Firstly, the source-detector and source-aperture distances are fixed on because of the neutron yield of Shenguang-Ⅲ facility. Then, base on the sharpness and isoplanaticity of the point spread function, the radii of the aperture are optimized. Finally, the resolution of the system is analysed, and the distortions induced by the aperture-fabrication error and misalignment are estimated by the simulation. According to the results, a resolution of 15 μm can be satisfied, the fabrication error should be limited to a maximum of 0.1, the precision of alignment should be better than 60 μm, the aperture rotation should be within 0.35 mrad, and the source-aperture distance error should be less than 1 mm.