Questions?

Optical Engineering in Houston, TX

Hello, Are you able to explain the below problem to me? Thank you.. Q1. Design a fiber optic endoscope to look for stomach ulcers. The field of view on the stomach wall should be one centimeter diameter, the viewing distance beyond the end of the endoscope should be 0.5 centimeters. The outside end of the endoscope is observed by a CCD television camera, using a 1/4 inch diagonal square CCD chip, three millimeters beyond the package window. At no place should the diameter of the endoscope exceed 0.5 centimeters. The television camera requires an equivalent scene illumination of 10 Lux. Design a fiber optic illuminator, coaxial with the endoscope, to provide sufficient illumination, and to illuminate the whole field. Q2 You wish to construct an X-ray system capable of resolving calcium accretions of 1.5 millimeter diameter in a subjects lungs. The system consists of an X ray tube placed one meter behind the subject and a photographic film cassette placed in contact with the front of the subject. Determine the maximum spot size of the electron beam in the X ray tube, which will give a full shadow of these lesions on the film. The X ray tube is operated at a potential difference of 100 Kilovolts, and the elestrons are emitted from a heated thoriated tungsten sheet. The emission density of electrons is 2100 milliamps per square centimeter at a sheet temperature of 2300K. Using the "Optic" program, or otherwise, design a transport which will deliver a minimum of 50 milliamps of electrons at an energy of 100 Kev to the impact spot of the electron on the X ray generating target. (Assume the angular part of the emission phase space is +-pi/2 and the energy of emitted electrons is KT). Instructions for the use of "Optic" and a sample data file are available on the Web page.

Sent by Olga on 4/21/12