Diffraction of Electromagnetic Waves by a Plane Wire Grating (Classic Reprint)


Book Description

Excerpt from Diffraction of Electromagnetic Waves by a Plane Wire Grating In the infrared region the grating constant is much greater than a wavelength. In this case one can assume that there is no interaction between the wires of the grating. The diffraction field is taken as the sum of diffrac tion fields of the individual wires of the grating, the field of any one wire calculated neglecting the other wiresl. The grating is assumed to consist of a set of infinite, parallel, equidistant, perfectly conducting circular cylinders. The set may be taken as finite, showing the background in addition to the various order spectra. Only the infinite grating will be considered here. This approach was extended somewhat by'twersky2 who included the first order interaction effects between neighboring elements in the case of an acoustic wave incident on a grat ing of perfectly rigid circular cylinders. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.













Diffraction of Electromagnetic Waves by a Plane Wire Grating II (Classic Reprint)


Book Description

Excerpt from Diffraction of Electromagnetic Waves by a Plane Wire Grating II Putting the values of the coefficients An thus obtained into differentiating with respect to r, and finally evaluating this derivative at r R. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.







A Biologically Inspired CMOS Image Sensor


Book Description

Biological systems are a source of inspiration in the development of small autonomous sensor nodes. The two major types of optical vision systems found in nature are the single aperture human eye and the compound eye of insects. The latter are among the most compact and smallest vision sensors. The eye is a compound of individual lenses with their own photoreceptor arrays. The visual system of insects allows them to fly with a limited intelligence and brain processing power. A CMOS image sensor replicating the perception of vision in insects is discussed and designed in this book for industrial (machine vision) and medical applications. The CMOS metal layer is used to create an embedded micro-polarizer able to sense polarization information. This polarization information is shown to be useful in applications like real time material classification and autonomous agent navigation. Further the sensor is equipped with in pixel analog and digital memories which allow variation of the dynamic range and in-pixel binarization in real time. The binary output of the pixel tries to replicate the flickering effect of the insect’s eye to detect smallest possible motion based on the change in state. An inbuilt counter counts the changes in states for each row to estimate the direction of the motion. The chip consists of an array of 128x128 pixels, it occupies an area of 5 x 4 mm2 and it has been designed and fabricated in an 180nm CMOS CIS process from UMC.