Abstract: A method of profiling a rough surface of an object includes moving the object along a z axis so that a highest point of the rough surface is optically aligned with and outside of the focus range of a solid-state imaging array. An interferogram of the rough surface then is produced by means of a two beam interferometer. The solid-state imaging array is operated to scan the rough surface along x and y axes to produce intensity data for each pixel of the solid-state imaging array for a plurality of frames each shifted from the other by a preselected phase difference. The modulation for each pixel is computed from the intensity data. The most recently computed modulation of each pixel is compared with a stored prior value of modulation of that pixel. The prior value is replaced with the most recently computed value if the most recently computed value is greater.

Abstract: An edge sensitive set-reset flip-flop is implemented by providing a conventional cross-coupled coincident gate flip-flop with an input means consisting of an inverter, a noninverting delay element and a coincident gate. The input means buffers binary input signals such that the cross-coupled coincident flip-flop will change state only in response to binary transitions of a prescribed direction.