Research on Echo Energy of Cat-Eye Target Based on Lasers Character of Polarization
Most of the military electro-optical (EO) systems, including optical observing and collimating systems, EO surveillance systems, EO tracking systems, EO search systems, EO fire control systems and EO distance-measuring systems, have reflective elements or partial reflective elements at the focal planes, such as modulate tray, cross image, lattice and photo-sensitive area of photoelectric detector. The collimating echo along the primary route can be formed when one of these systems is irradiated by incidence laser. This echo energy is two to four orders of magnitude greater than normal diffuse reflectors echo energy in the aspect of order of magnitude. This phenomenon is called cat-eye effect and so these electro-optical systems are called cat-eye targets. Presently research on transmission and reflective energy of cat-eye target from the view of geometrical optics is the main study aspect and a lot of field use these research results into application, such as active laser detection system, retro-reflector, optical communication and target identification. To a certain extent all of the optical systems can change polarization state of laser wave. For example, optical lens or reflecting mirror can cause the incident lasers transformation of polarization state and phase delay. In this paper, the cat-eye target is regard as the combination of a thin lens and a reflecting surface. In accordance with path of light beams propagation in the cateye target, this target is unfolded along the reflecting surface symmetrically, and forms a 4-f system model. That is to say, a polarization converter is set at the con-focal plane of two lenses. According to the Fresnels law and the theory of Jones matrix, echo energys characteristic equations of normal incident polarization laser through cat-eye target are theoretically deduced in detail by using ray tracing method. The character of thin-lens systems echo energy is quantitatively analyzed by Matlab and the discipline of different incident lasers azimuth and coordinate is discussed. The simulation results indicate that the output polarization lasers amplitude would be subdued to 0.034 times of the incident lasers amplitude after the refraction and reflection of cat-eye target, which has nothing to do with the focal length of cat-eye target, while the polarization degree and polarization state are almost not affected. Moreover, as for other diffuse reflecting target, the polarization characteristics of echo laser will be changed obviously. These results are valuable for the active laser detection, target recognition of laser radar and the cat-eye retro-reflector in optical communication.
laser polarization cat-eye target echo energy Jones matrix
Bin Zhou Bingqi Liu Dongsheng Wu
Department of Optics and Electron Engineering, Ordnance Engineering College, Shijiazhuang Hebei, Chi Department of Optics and Electron Engineering, Ordnance Engineering College, Shijiazhuang Hebei, Chi Department of Optics and Electron Engineering, Ordnance Engineering College, Shijiazhuang Hebei, Chi
国际会议
2011 International Conference on Electronics and Optoelectronics(2011电子学与光电子学国际会议 ICEOE 2011)
大连
英文
302-305
2011-07-29（万方平台首次上网日期，不代表论文的发表时间）