精确计算红外焦平面冷屏立体角的方法  

Method of accurate calculation of solid angle cold shield for infrared focal plane array

作　　者：李建林[1] 孙娟[1] 周效军[1] 

机构地区：[1]昆明物理研究所,云南昆明650223

出　　处：《红外与激光工程》2012年第5期1153-1157,共5页Infrared and Laser Engineering

基　　金：国防预研项目

摘　　要：制冷型探测器的冷屏蔽能有效地抑制来自背景的光子噪声。冷屏设计和能量计算都需要精确计算冷屏立体角。在工程设计中,仅有圆形和矩形正锥面立体角的精确计算公式,没有其他形状正锥面和斜锥面立体角的计算公式。由空间立体角矢量积分得到了直角坐标系积分公式,给出了有效权重立体角计算公式。针对圆形、椭圆形、矩形、田径场形和异形冷屏孔,将斜锥面转换成正锥面,分析计算了它们的积分区间,用MATLAB积分函数int()计算了冷屏立体角的精确值。解决了轴上像元和轴外像元接收辐射立体角的计算问题。Cold shield of cooling infrared detectors can suppress photons noise of background effectively. The accurate calculations of solid angle of FPA are used in design of cold shield and calculation of radiant energy. In engineering design, there are only formulas for the accurate calculation of cold shield solid angle for symmetric circular and rectangle cold aperture geometry in sphere coordinate system. Solid angle formula in rectangular coordinates was derived from vector integral formula in space solid angle, which produces the effective weight solid angle integral formula and calculating formula. To calculate accurately solid angle of cold shield in rectangular coordinates by function int（ ） in MATLAB, oblique cone was converted into right cone. Useful solid angle of right cone and oblique cone were calculated and integral region were analyzed such as symmetric round, ellipse, rectangular, athletic field-shaped and special-shaped cold shield. Cold shield solid angle of on-axis pixel and off-axis pixel on FPA were calculated.

关 键 词：红外焦平面阵列 冷屏 立体角 

分 类 号：TN215[电子电信—物理电子学] TN219