利用螺旋型波带片进行边缘增强成像

为了提高对等离子体内界面区域的诊断精度,研究了利用螺旋型波带片实现边缘增强成像的技术。制作了用于可见光波段的一阶螺旋型波带片,最外环宽度3μm。利用螺旋型波带片对振幅式物体进行了边缘增强成像,实验获得了成像物体内边界区域的清晰图像,界面区域的成像强度得到很大增强。通过实验测量发现,当物距在菲涅耳衍射区域内时,螺旋型波带片也能够获取较好的成像质量,表明螺旋型波带片具有较大的视场角,能够对大尺度物体进行边缘成像。基于螺旋型波带片的边缘增强成像可以弥补传统成像方式对界面区域成像的不足,提高对等离子体内界面区域的诊断能力。

Edge enhancement imaging using spiral zone plate

This paper studies the edge enhancement imaging using a spiral zone plate(SZP), which can improve imaging quality of the border areas inside the plasma. An SZP was fabricated for the visible light imaging with the outmost width of 3 μm. Edge-enhanced imaging of amplitude objects were carried out using the SZP. High quality images of edges in the amplitude objects were obtained in our experiments and the intensity of edges areas in the images was improved greatly. Experimental analysis shows that high quality edge-enhanced imaging can also be obtained using SZP even when the separation between the objects and optics is in the Fresnel diffraction ranges. This means that the spiral zone plate can provide a wide field of view and can be used for large-size object imaging.