網址: https://www.researchgate.net/profile/Dirk-Puhlmann/publication/243580671/figure/fig1/AS:298443567321088@1448165899326/Diffraction-efficiency-for-the-first-order-of-diffraction-in-dependence-of-the.png
網址2: https://www.researchgate.net/figure/Diffraction-efficiency-for-the-first-order-of-diffraction-in-dependence-of-the_fig1_243580671
