三温区梯度化学气相沉积ZnS制备  

TTG-CVD based ZnS material preparation

作　　者：吴绍华 黄攀[3] 赵劲松 赵跃进 郑丽和[5] 董汝昆[3] Wu Shaohua;Huang Pan;Zhao Jingsong;Zhao Yuejin;Zheng Lihe;Dong Rukun(School of Physics,Beijing Institute of Technology,Beijing 100081,China;Kunming Institute of Physics,Kunming 650217,China;Yunnan KIRO Photonics Co.,Ltd.,Kunming 650217,China;School of Optics and Photonics,Beijing Institute of Technology,Beijing 100081,China;School of Physics and Astronomy,Yunnan University,Kunming 650500,China)

机构地区：[1]北京理工大学物理学院,北京100081 [2]昆明物理研究所,云南昆明650217 [3]云南北方光学科技有限公司,云南昆明650217 [4]北京理工大学光电学院,北京100081 [5]云南大学物理与天文学院,云南昆明650500

出　　处：《红外与激光工程》2021年第10期172-177,共6页Infrared and Laser Engineering

基　　金：云南省科技创新强省计划专项(2014AA023);国家自然科学基金联合基金(U1830104)。

摘　　要：红外热像仪可在全天候条件下实现目标识别,在安防、夜视辅助及红外测温系统等领域应用广泛,但红外热像仪成像质量和效果受制于ZnS红外光学镜头的品质和性能。文中采用自主研制的三温区梯度化学气相沉积(TTG-CVD)及退火热处理制备ZnS块体。采用X射线衍射表征出ZnS块体是立方闪锌矿结构,具有光学各向同性,可以满足后续在红外光学镜头中的设计需求。结合红外透过光谱获得ZnS块体在8~12μm长波红外波段的平均透过率达71.6%。ZnS块体在1.06μm处的折射率均匀性为1.94×10^(-5)。进一步采用光学冷加工和单点金刚石车削等工艺,制作出ZnS红外光学透镜和红外镜头。红外光学镜头在空间频率为20 lp/mm时,在半视场(0.5视场)和0.707视场的调制传递函数(MTF)接近衍射极限。红外成像系统在中心视场、0.707视场由像差引起的弥散斑均方根值(RMS)均小于像元尺寸20μm,系统畸变小于1%,各项指标均达到实际使用要求。Infrared thermal imagers are widely used in security,night vision and infrared temperature measurement with the advantages of target recognition under all-weather conditions.However,the imaging quality is restricted by the quality of ZnS infrared optical lens.The annealed ZnS bulk was fabricated through Three-Temperature zone Gradient Chemical Vapor Deposition(TTG-CVD)furnace.The ZnS bulk with cubic sphalerite structure was characterized by X-ray diffraction.No hexagonal wurtzite structure was detected.It indicates that ZnS bulk possessing optically isotropic property,which can meet the design requirements in lens.The average transmittance of ZnS bulk was measured as 71.6%in the long-wavelength infrared band of 8-12μm.The refractive index uniformity of ZnS bulk was measured as 1.94×10^(-5)at 1.06μm.As encouraged by the above optical parameters,ZnS infrared optical lens was further produced by adopting optically cold-mechanical process and single-point diamond turning techniques.When the spatial frequency of ZnS infrared optical lens was 20 lp/mm,the modulation transfer function(MTF)of the half or 0.707 field of view was close to the diffraction limit.The root mean square value(RMS)of the diffuse speckle caused by aberration in the central field and 0.707 field of view was less than 20μm in the pixel size.Meanwhile,the system distortion was less than 1%in the infrared imaging system.It shows TTG-CVD based ZnS crystal is promising for infrared applications.

关 键 词：ZnS块体 折射率均匀性 红外光学镜头 调制传递函数 红外成像 

分 类 号：O734[理学—晶体学] O435[机械工程—光学工程]