Venkanna Mekala, Karuna Sagar Dasari
The analytical studies were made for obscured apertures apodised with amplitude filter under the influence of defocus. The coherent edge-response of optical systems apodised with shaded aperture in the case of shrink aperture has been studied. The image quality assessment parameters have been evaluated by masking the aperture from the outside. Results are drawn for various obscured apertures and compared with and without apodisation. It is found that, this type of shading and shaping of apertures is found to be effective in enhancing the image quality and the resolving power of the optical imaging systems.