精确计算红外焦平面冷屏立体角的方法
吨的认识教学设计-学生会主席竞选稿
第41卷第5期
VO1.41 NO.5
红外与激光工程
Inf
rared and Laser Engineering
2012年5月
Mav.20
12
精确计算红外焦平面冷屏立体角的方法
李建林,孙娟,周效军
(昆明物理研
究所,云南昆明650223)
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intO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。
关键词:红外焦平面阵列
; 冷屏; 立体角
中图分类号:TN215;TN219 文献标志码:A 文章编号:1007—
2276(2012)05一l153—05
Method of accurate calcul
ation of solid angle cold shield
for infrared
focal plane array
Li Jianlin,Sun Juan,Zhou Xia
ojun
(Kunming Institute of Physics,Kunming 650
223,China)
Abstract:Cold shield of coohng infr
ared detectors Can suppress photons noise of backg
round effectively.
The accurate calculations o
f solid angle of FPA are used in design of cold sh
ield and calculation of
radiant energy.In engi
neering design,there are only formulas for the acc
urate c ̄culation of cold shield
solid angle fo
r symmetric circular and rectnglae cold aperture g
eometry in sphere coordinate system.Solid
ngla
e formula in rectangulr coordinates was deraived f
rom vector integral formula in space solid angle,
which produces the effective weight solid angl
e integral formula and c ̄culating formula.To calcu
late
accurately solid angle of cold sielhd in
rectangular coorinatdes by function im()in MATLAB,
oblique cone
was conve ̄ed into right cone.Usef
ul solid angle of right cone and oblique cone were
calculated and
integral region were analyzed
such as symmetric round,ellipse,rectangular,athlet
ic field—shaped and
special—shaped cold shield
.Cold shield solid angle of on-axis pixel and off-
axis pixel on FPA were
calculated.
Key wor
ds:infrared focal plane array;cold shield;solid an
gle
收稿日期:2011—09—22;修订13期:2011—10—19
基金项目:
国防预研项目
作者简介:李建林(1963-),男,高级工程师,主要从事红外探测器封装和测试技
术方面的研究。Email:lijinalinl2@2lcn.com