激光照射性能测量中异源相机的标定方法

激光照射性能测量相机包括可见光相机和近红外相机,可完成激光照射器照射精度立靶成像测量。可见光相机用来拍摄运动靶板,近红外相机用来拍摄照射激光。为解决在测量过程中卡塞格林光学系统使图像产生畸变和两个相机光轴不严格一致问题,在远距离测量中忽略透视误差的影响,对张正友相机标定方法进行改进,使相机内参数中扭曲因子为0,实现相机标定;根据可见光相机和近红外相机成像面的空间透视关系,实现双相机轴线一致性标定。实验结果表明:可见光相机标定的重投影误差为0.08像素,近红外相机标定的重投影误差为0.19像素,相机配准轴线一致性精度为0.37μrad,满足激光照射器照射精度外场测试中的需求。

防激光、防眩光PMMA材料的应用性能

以聚甲基丙烯酸甲酯(PMMA)为基材,加入防激光、防眩光吸收剂IR530、IR580、IR1065,制备了能有效吸收530 nm、1 060 nm波长激光和500～580 nm波长眩光的PMMA材料,对其防护性能、力学性能、耐老化性能和耐激光照射性能进行了研究.结果表明,防激光、防眩光PMMA材料对530nm波长激光的透过率为0.01%,对1 060 nm波长激光的透过率为0.02%,对500～580 nm波长范围眩光的透过率小于等于0.1%,具有良好的防护性能;防激光、防眩光PMMA材料的冲击强度较高,为10.6 kJ/m2,且有良好的耐紫外老化性能.

Giant negative photoresistance of epitaxial manganite La_(2/3)Ca_(1/3)MnO_(3-δ) film

The La2/3Cal/3Mn03_σ film has been deposited on the （001） SrTiO3 substrate and its temper- ature-dependent photoconductive properties have been investigated from 80 to 300 K. The La2/3Cal/3MnO3-σ film has a novel photoelectric property due to its oxygen-deficient structure. We observed laser-induced giant negative photoresistance of the sample in a wide temperature range. The change rate of negative photoresistance was nearly 100% at the low temperature when the sample was irradiated by 532 nm laser. In addition, this effect was sensitive to the power of laser irradiation. The oxygen-deficiency of La2/3Cal/3Mn03-σ film seems to have an impact on the laser-induced resistance variation. The experimental results made the La2/3Cal/3MnO3_σ film a promising application as a photoswitch device.