先用斯忒潘-玻尔兹曼定律计算小孔的温度,由M0(T)=σT^4 =>T=(M0(T)/σ)^(1/4)=(W/Sσ)^(1/4)由普朗克公式可知,M0λ(T)=2πhc^2λ^(-5)/[e^(hc/λkt)-1]先将小孔在λ到λ'范围内的单色辐出度看做不变（不然太麻烦了囧...