Transmissivity Testing System Of The Plume Penetrated By Laser

Various kinds of laser weapons basing on laser technology force us to develop the counter-measure promptly to maximally reduce the damage and occupy the favorable position in the modern war. Smoke interfering is one of the commonly used methods. Therefore, the smog ingredient research becomes the urgent topic in recent years, and the attenuation characteristics which laser transit smoke is one of important aspect on smog ingredient research. It is significant for laser guidance and infrared countermeasure. Main task of the subject is to test dynamically transmissibility which laser passes the aircraft engine plume. Firstly, We analyze the smog essence and the principle of closing over infrared radiation and the measuring technique in detail. Several methods of testing presently transmissibility are introduced and compared. We used the method of high precision and simple structure. Then we propose the overall layout of testing laser plume transmissibility system, which discussed the overall structure and working scheme. The system is divided into two major parts: optical system and signal acquisition and data processing system. This article has emphasized the optical system composition and the work process. We elaborate the design process of optical system in part of optical system design. Finally, two design results according with system requests are listed. The effect of spherical aberration on the radius of image beam waist in the design of laser optical system is discussed in detail,and the expression is presented. Radius variation of image beam waist due to spherical aberration, which varies with the position of objective beam waist, and optical system focus is analyzed with the form of curve. At last,a design example of optical system used for laser plume attenuation testing system is given to illustrate the effect of spherical aberration on the image beam waist. The testing system software has been programmed in Delphi software development environment after the design satisfied for demands. We analyze the testing results after system passing test experiment, which proved this system to accord with the design request. The error of atmospheric disturbance and attenuation flake are calculated and analyzed. The error estimation and the source of error in testing are given. It proves that this method has great practical value.