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.