1u+1v=1f\dfrac{1}{u}+\dfrac{1}{v}=\dfrac{1}{f}u1+v1=f1
1f=(μ−1)(1r1+1r2)\dfrac{1}{f}=(\mu-1)\left(\dfrac{1}{r_{1}}+\dfrac{1}{r_{2}}\right)f1=(μ−1)(r11+r21)
μv+1v=μ−1r\dfrac{\mu}{v}+\dfrac{1}{v}=\dfrac{\mu-1}{r}vμ+v1=rμ−1
m=uv(1+Df)m=\dfrac{u}{v}\left(1+\dfrac{D}{f}\right)m=vu(1+fD)