基于曲面传感器的大孔径1300万像素手机镜头设计

设计了一款由5片塑料非球面透镜组成的1 300万像素大孔径手机镜头。将曲面传感器引入镜头设计,在不增加镜片数量以及保证大光圈的基础上改善了边缘像质,解决了边缘失光问题。系统采用1/3英寸(4.8mm×3.6mm),长宽比为4∶3的曲面传感器。该镜头的焦距为3.5mm,F数为1.55,视场角为74°,全视场调制传递函数(MTF)均大于0.4,最大畸变小于3.5%,相对照度大于55%,可以获得良好的成像效果。镜头公差灵敏度较低,能满足加工条件。

小型化同心反射式手机镜头设计

基于现代社会对手机镜头高像素、小型化的要求,基于同心透镜原理设计了同心反射式手机镜头。通过光路计算,求解了系统的球差表达式,进一步获得了系统的初始结构。利用光学设计软件设计了光学系统,镜头采用像元大小为1.25μm的曲面传感器,光学系统的F数为1.8,焦距为2.7 mm,最大全视场角为100°,系统总长为2.7 mm。设计结果表明,在空间截止频率400 lp/mm处,0.7视场的调制传递函数均大于0.34,全视场的调制传递函数均大于0.23,各视场的弥散斑半径均小于艾里斑。在全视场内,相对照度高于0.64,该设计满足手机镜头成像要求。

AIRCRAFT MOTION PARAMETER ESTIMATION VIA MULTIPATH TIME-DELAY USING A SINGLE GROUND-BASED PASSIVE ACOUSTIC SENSOR

The time-frequency analysis of the signal acquired by a single ground-based microphone shows a two-dimensional interference pattern in the time-frequency plane,which is caused by the time delay of the received signal emitted from a low flying aircraft via the direct path and the ground-re-flected path. A model is developed for estimating the motion parameters of an aircraft flying along a straight line at a constant height and with a constant speed. Monte Carlo simulation results and ex-perimental results are presented to validate the model,and an error analysis of the model is presented to verify the effectiveness of the estimation scheme advocated.