This book investigates the Point Spread Function (PSF) for many apertures either modified in its circular shape or deformed using Kidney and elliptic shapes. The modulation in apertures is considered to be linear, quadratic, linear- quadratic, and longitudinal strips inside the circular aperture. The discrimination between apertures is based on speckle imaging and Fourier optics techniques. In addition, higher order apertures are investigated and the amplitude impulse response or the PSF is computed. In all modulated apertures described in this book, we tried to improve the microscope resolution either conventional or the confocal laser microscope.