నైరూప్య

Improving the Edge Imaging Characteristics of Aberrated Coherent Optical Systems by Variable Apodisation Method

Venkanna Mekala and Karuna Sagar Dasari

The coherent edge-response of aberrated optical systems apodised with amplitude filters has been studied theoretically. The two most common problems encountered in the coherent-imaging techniques are speckling and edge-ringing. The pronounced effects of edge-ringing associated with coherent images of straight edges can be considerably reduced using variable apodisation technique. It is found that this type of apodisation is more effective not only in trimming the ringing-effect and also improves another image quality assessment factor edge gradient perceptibly which improves the edge images under the influence of defocus and primary coma. Studies on this subject indicate the importance of coherent imagery in areas like spatial filtering technique and microscopy