高速线扫描共焦检眼镜

高速线扫描共焦检眼镜使用线光束照明眼底视网膜,同时利用线阵CCD对视网膜平面的单次散射线光束探测成像。系统光学放大率为7倍,横向分辨率小于10μm,对于58kHz线频的1024pixel×512pixel成像模式,成像帧频高达110frame/s。该系统实现了高分辨率、高帧频模拟人眼实验图像的获取。     

基于PCA/ICA和误差补偿算法的眼镜摘除研究

眼镜遮挡对人脸图像识别率影响较大,为了提高戴眼镜人脸图像的识别率,需要摘除正面人脸图像中眼镜。采用PCA和ICA算法提取了二阶统计信息、高阶信息,较好地刻画了人脸的细节特征;同时结合灰度补偿算法,弥补了由于戴眼镜图像未参与特征空间的训练过程中所造成的合成图像中人脸表情的失真;利用反复的迭代补偿算法进行人脸重建。通过Yale人脸数据库进行仿真实验结果表明:该方法合成的图像没有眼镜的痕迹,看起来更加自然,有效地改善了戴眼镜图像的面部特性,提高了人脸的识别率。     

德发明家设计滤镜效果眼镜可直接拍照上传

德国发明人马库斯·格尔克设计了一款新型眼镜，拥有lnstagram功能。这款眼镜内置一个5 Mpixel传感器，可利用内置电脑为真实世界的景象添加滤镜效果。格尔克的灵感来源于谷歌、奥林巴斯和爱普生的眼镜电脑。他表示：“佩带者只需推一下‘Insta’，就能激活眼镜，选择不同的滤镜。此外，用户也可以用眼镜拍照，而后直接将照片上传到Instagram。”     

Femtosecond measurement of third-order optical nonlinearities in Bi_2O_3-B_2O_3-BaO glasses

We present the measurement of the third-order nonlinearity of Bi203-B~O3-BaO glasses using the single Z-scan method with femtosecond laser pulses at 750 - 850 nm. Both third-order nonlinear refraction γ and two photon absorption coefficient β are investigated. The γ shows an increasing tendency with increasing BaO content, and the largest value is estimated to be 7.2×10^-14 cm^2/W, which is as large as those of chalcogenide glasses. The dependence of 13 on the normalized photon energy is studied.     

新型光纤让看3D电影不戴眼镜

麻省理工学院的电气工程师和材料科学家近日制造出一种神奇的光纤，用其编织成的柔性显示屏可以播放3D图像而观众不必佩戴特制眼镜来观看。该研究近期发表在《自然-光子学》网站上。     

Broadband Infrared Luminescence from Bismuth-Doped GeS2--Ga2S3 Chalcogenide Glasses

Near-infrared luminescence is observed from bismuth-doped GeS2-Ga2Sa chalcogenide glasses excited by an 808 nm laser diode. The emission peak with a maximum at about 1260 nm is observed in 80GeS2-2OGa2 Sa：O.fBi glass and it shifts toward the long wavelength with the addition of Bi gradually. The full width of half maximum （FWHM） is about 200 nm. The broadband infrared luminescence of Bi-doped GeS2-Ga2Sa chalcogenide glasses may be predominantly originated from the low valence state of Bi, such as Bi＋. Raman scattering is also conducted to claxify the structure of glasses. These Bi-doped GeS2 Ga2Sa chalcogenide glasses can be applied potentially in novel broadband optical fibre amplifiers and broadly tunable laser in optical communication system.     

偏振眼镜立体显示的立体串扰度及其影响因素

偏振眼镜立体显示是使用偏振片来分离左右眼图像的,偏振片的参数决定了偏振眼镜立体显示的性能好坏。提出了偏振眼镜立体显示的立体串扰度概念,推导了立体串扰度与偏振片旋转角度和偏振片偏振度的关系式。结果表明,立体串扰度随偏振片旋转角的变大而增大,随偏振片偏振度的增大而减小。因此为偏振眼镜立体显示的性能改善提供了依据。