设计了一款宽光谱日夜两用鱼眼监控镜头,使用近红外LED光源照明及IR-CUT双滤光片,近红外波长为850 nm,采用Zemax软件的多重配置结构设计,使用固定焦距,实现可见光和近红外光的共焦。对设计的光学系统结构和像差曲线进行分析,设计全视场角和相对孔径分别为175°和1/1.8,使用1/3 in CCD成像接收器件,全视场MTF值在空间频率100 lp/mm处达到0.3。
The output characteristics of neodymium-doped gadolinium vanadate(Nd:GdVO4) crystals laser with dual c-axis orthogonal gains end-pumped by two fiber-coupled diode lasers are investigated. With two 1 W semiconductor diode lasers pumping, the output power of TEM00 laser is 920 m W, and the optical conversion efficiency is close to 46%. By changing the relative orientations of both Nd:Gd VO4 crystals, the polarization characteristics of laser are varied. In particular, by keeping the c-axes of two Nd:Gd VO4 crystals orthogonal to each other and adjusting two diode pump lasers to operate at the same power level, the completely unpolarized light is obtained.
