Optical components in large aperture optical imaging system are susceptive to intense laser radiation. Optical band pass filter for spectra selection and nonlinear filter for intense laser blocking, are usually focal or near focal elements in imaging system, will more likely to be permanently damaged by high intense unwanted laser irradiating. In order to relate the optical imaging performance degradation to laser irradiating parameters, characteristics of the damage sites and so on, a test facility consisting of scaled electro-optical imaging system and standard imager evaluation system was constructed, and the linear spread function, modulation transfer function, signal transfer function, and noise power spectrum were obtained. Experimental imaging performance degradation law of damaged fused silica and colored glass filters were analyzed. Furthermore, some brief discussions on the imaging performance degradation mechanisms are also presented.
Based on the invariable stretching stress preloading device, the experimental investigation on damage effect of 30CrMnSiA steel structure specimen by continuous laser was carried out. While the stress is between 660MPa and 1140MPa, the average laser power density is between 110W/cm2 and 330W/cm2, we can get the conclusions as follow: (1) When the preloaded stretching stress increases, the necking phenomenon becomes unobvious. (2) When the preloaded stretching stress increases, both the rupture time and rupture temperature decrease monotonously. (3) When the laser power density increases, the rupture time decreases monotonously. (4) When the preloaded stretching stress or laser power density increases, the rupture threshold decreases monotonously. (5) The strain of the specimen before necking is small, and the specimen metamorphoses during necking period and the deformation of specimen is centralized in the necking region.