Professor Emeritus
Professor Emeritus
- 1968 – 1972 Graduate School of Arts and Sciences
- University of Pennsylvania, Philadelphia, PA
- Received degree of Doctor of Philosophy
- Major in Electrical Engineering;
- Specializing in electrooptics.
- Dissertation: “Millimeter Wave Detection with Glow Discharge Plasmas and its Application to Holography”
- Advisor: Prof. N.H. Farhat
- Support: National Aeronautics and Space Administration
- Fellowship, 1968 to 1971.
- 1966 – 1968 Moore School of Electrical Engineering
- University of Pennsylvania, Philadelphia, PA.
- Received degree of Master of Science in Engineering
- Major in Electrical Engineering, specializing in
- communication theory and electrooptics.
- Title of Master’s Thesis: “Optical Speed Sensing”
- Advisor: Prof. J. Bordogna
- Support: Moore School Research Assistantship,
- 1966 to 1968. Work on laser theory and applications.
- 1962 – 1966 Moore School of Electrical Engineering
- University of Pennsylvania, Philadelphia, PA.
- Bachelor of Science in Engineering, Major in
- Electrical Engineering.
- Imaging through the atmosphere and restoration from such blur.
- Imaging in the presence of image vibrations and motions and restorations from such blur.
- Imaging system theory.
- Target acquisition.
- Terrahertz detection and imaging
- 1. Imaging for automobile safety
- 2. Imaging through the atmosphere
- 3. Atmospheric optics
- 4. Terrahertz imaging
- 1. Imaging for automotive safety . This involves an active imaging system developed by an Israeli company Elbit, Ltd, in which infrared laser pulses are used to illuminate the road ahead up to about 250-300 meters, which is far more than the 50 meters associated with low-beam headlamps. However, strong back reflections from road signs tend to blind the image of the road over the whole region near the sign, and also prevent reading of the sign. We have developed techniques to remove the blindness from the image, and to allow the road signs to be read from much greater distances than can be done with car headlamps. By providing imaging of the road for almost 300 meters instead of the normal 50 with headlamps, we hope we will make a contribution to road safety. Also, by using range-gating techniques, this system can see through all sorts of adverse weather conditions such as fog, rain, snow, etc. (O. David, N.S.Kopeika, and B. Weizer, “Range-gated active night vision system for automobiles”, Applied Optics , vol. 45, pp. 7248-7254, 1 Oct. 2006.) Elbit is in contact with GM, Ford, and various European automobile manufacturers. It is felt that solving this problem might lead to a major breakthrough into the international auotomobile market. This project is supported by The Ministry of Commerce and Industry. The research is carried out by Dr. Yitzhaky, a postdoc in the Electrooptical engineering Unit, Ofer David who is both an engineer at Elbit and a Ph.D. student in the Electrooptical Engineering Unit – beintichumi, and various students in both Electrooptical Engineering and Electrical and Computer Engineering. Ofer David has been approved to receive his degree at the next Ph.D. graduation. Additional papers are waiting approval by Elbit prior to submission.
- 2. Imaging through the atmosphere . Optical turbulence and aerosols [very small particles carried by the atmosphere] blur and attenuate images, especially over long lines of sight. Such blurring makes it very difficult to distinguish small objects, or even long objects that are very narrow, such as missiles including kassam missiles. Using the Elbit automobile safety imaging system, we demonstrated with some very preliminary image processing that we are able to provide computer correction of atmospheric blur so as to image kassam missiles in trucks many kilometers away. We were on the verge of being awarded a project from the Ministry of Defence this past summer to develop this further, when the Lebanon War broke out. Hopefully, we will be awarded such a project in the near future. This research too is run by Dr. Yitzhaky, Prof. Kopeika, and various students. A provisional patent has been applied and several papers have been recently published/ submitted toward this goal.
- 3. Atmospheric optics. Optical turbulence is variations in the refractive index of the atmosphere. These are random in both time and space. They cause image dancing and blur. An example can be looking at objects where the line of sight passes over Sabbath candles, or over a toaster. In such cases, the heat causes atmospheric refractive index variations, and the objects appear to be dancing randomly and are blurred. Outside, the heating of the earth’s surface by the sun causes similar effects, so that on hot days images appear blurred and dancing. We investigate the vertical profile of such phenomena up to about 14 km elevation. This is important to satellite optical communication and to imaging from high elevation platforms such as planes and satellites. It is also very important for high intensity laser weaponry to destroy incoming missiles. We use a high intensity laser to transmit very short light pulses high into the atmosphere, and study the image dancing at various altitudes of the light pulse. This is a LIDAR, or light radar system. Our results indicate that assumptions (Kolmogorov model) used to describe such effects higher up in the atmosphere are incorrect. We are measuring and modeling what actually takes place. This means that much of the atmospheric turbulence modeling for above the boundary layer is incorrect, and has to be fundamentally revised. This is extremely important for laser weaponry, where turbulence modeling until now has been Kolmogorov. The US Air Force Airborne Laser Division [ABL], for example, which has been heavily involved in schemes involving high intensity lasers to destroy incoming missiles, has based its work upon Kolmogorov modeling. This basic research is sponsored by the highly prestigious Israel Science Foundation [ ISF ]. It is being carried out by Arkadi Zilberman, who recently submitted his Ph.D. dissertation in The Department of Electrical and Computer Engineering, Dr. Efim Golbraikh of the BGU MHD Center, and Prof. Kopeika (E. Golbraikh and N.S. Kopeika, “Behavior of the structural function of the refraction coefficient in different turbulent fields”, Applied Optics , vol. 43, pp. 6151-6156, 20 November, 2004; E. Golbraikh and N.S.Kopeika, “Turbulence strength parameter in laboratory and natural optical experiments in non-Kolmogorov cases,” Optics Communications , vol. 242, pp. 333-338, 8 Dec., 2004; E. Golbraikh, H. Branover, A. Zilberman, and N.S.Kopeika, “Non-Kolmogorov atmospheric turbulence and optical signal propagation”, Nonlinear Processes in Geophysics , vol. 13, pp.297-301, 2006.)
- 4. Terrahertz imaging . The terrahertz [THz] spectral region is between the infrared and radio wave portions of the electromagnetic spectrum. Image quality is not as good as at optical wavelengths, but much better than at radio wavelengths where imaging is ordinarily impractical because of the very extensive diffraction blur. The advantage of THz waves over light waves is that THz waves penetrate all clothing, and basically anything that is not metallic. This means that in THz images people appear somewhat fuzzy but completely naked, so that anything concealed on their body or clothing is imaged. This is much better than a metal detector because here one obtains an image.
- There is great interest in developing THz imaging systems for use at airports, trains, bus stations, shopping centers, etc. There is no known biological hazard to THz imaging. Such systems have already been developed, but are prohibitively expensive, costing hundreds of thousands of dollars, because of the detector. We have found a very cheap [about 20-50 cents] but sensitive THz detector in research sponsored by the US Office of Naval Research [ONR] and the U.S. Army night Vision Lab. At their request, we have submitted a proposal to develop a real time THz camera for imaging of concealed objects at up to 100 meter distance. We think we can develop real time THz imaging systems costing about only 1% of those presently available. We have been informed by the US sponsors that the funds for the first year of this continuation project have already been approved. The project is expected to last three years, at a total budget of about $600,000. However, based on milestones, each year must be approved separately. This research is carried out by Prof. Kopeika of BGU, BGU graduate students in Electrooptical Engineering, and Dr. Abromovitch of The College of Judea and Samaria who is head of the terahertz lab there. A major portion of the THz camera work is to be carried by BGU Prof. Yadid-Pecht of The Electrooptical Engineering Unit and The VLSI Center which she heads. Dr. Yitzhaky is to be called upon to add image processing to improve the image quality.