Scheme And Optical Design Of Airborne Directional Laser Interference System

As a new infrared interference method,the directional jamming system can effectively improve the survivability of the flight platform under the threat of infrared guidance.Most existing directional interference systems generate interference signals by modulating infrared light sources.Such low-energy interference systems have poor interference effects on imaging seekers,and high-energy light sources need to focus on the target to produce higher energy density.This can blind or even destroy the target.This kind of jamming system similar to laser weapons needs to have the ability to focus at different distances and to accurately detect and track the target at all times,so it is necessary to conduct in-depth research on this common-caliber tracking and launching system.This article will discuss the performance of relevant parameters of this high-energy laser emission tracking system,and design the tracking system based on the analysis results and index requirements.In this paper,based on the propagation equation of the Gaussian beam,the focusing characteristics of the card system are simulated and analyzed,and the existing spot aiming model is improved,so as to determine the structural parameters of the launching system and put forward requirements for the tracking accuracy of the system;The two-level tracking system proposes an overall plan,and selects the rough tracking and fine tracking optical systems based on the target characteristics,and the optical system parameters are demonstrated;based on the demonstration parameters,each system is optically designed,and the Image quality evaluation was performed on different systems;finally,tolerance analysis and focus analysis were performed on the designed system.The designed beam expansion system adopts a coaxial non-focusing card structure and a hollow flat-top beam for beam emission.Both the primary mirror and the secondary mirror are designed with a conical surface,and the beam can be moved within the range of 1km?4km by the forward and backward movement of the secondary mirror Carry out focusing,the focusing accuracy is better than 0.1?m.The tracking system is a two-stage tracking system,in which the coarse tracking system is a mid-wave infrared system,with a large field of view of 5°×4° for preliminary target capture.The precision tracking system and the launching system adopt a common aperture design,which can achieve better imaging quality for targets at different positions in the field of view of 2mrad×2mrad.The two-level system satisfies the principle of visual field transition,which enables the system to quickly capture thetarget and theoretically enables the tracking accuracy of the system to be better than20?rad.The designed system parameter structure is simple,the image quality meets the requirements,the tolerance allocation meets the actual processing and manufacturing,and the focus error has little effect on the launch system and the tracking system.The detailed analysis and demonstration of the parameters of each system are expected to provide guidance for the design of directional laser interference system.