1. A process for deriving three-dimensional information from a series of two-dimensional images which can be obtained without changing the position of the detector or its focus comprising: obtaining at least three two-dimensional images of the same object: one centered image with aperture positioned on the central optical axis; and two or more directional images taken with same numerical aperture but with the apertures located at different off axis positions; wherein the image is sectioned into many depth layers such that the image in each layer is decoupled from other layers using point spread function associated with the imaging system, the image in each layer is sharpened independent of other layers, and the image is displayed indicating the three-dimensional structure of the imaged object.