切換到寬版
  • 廣告投放
  • 稿件投遞
  • 繁體中文
    • 2217閱讀
    • 1回復(fù)

    [討論]當(dāng)導(dǎo)光板的出光面刻有光柵,那么當(dāng)入射角大于臨界角時(shí),它會(huì)全反射而不衍射嗎? [復(fù)制鏈接]

    上一主題 下一主題
    離線pan2qfly
     
    發(fā)帖
    16
    光幣
    16
    光券
    0
    只看樓主 倒序閱讀 樓主  發(fā)表于: 2015-10-26
    各位大大,最近我在看一篇二區(qū)的論文,題目是Grating_micro-dot_patterned_light_guide_plates_for_LED_backlights,Seung Ryong Park,2007。作者在里面提到,團(tuán)隊(duì)的導(dǎo)光板設(shè)計(jì)理念是通過(guò)在導(dǎo)光板上表面刻正弦型光柵,使得光以衍射-1級(jí)主級(jí)大出射,如圖所示。那么在作者所希望達(dá)到的出射情況(摘自原文)“when δi=0, all diffracted orders are located in the x-o-z plane as shown in Fig. 2(b). This grating diffraction geometry is referred to as classical “in-plane diffraction.” Under this condition with a sufficiently large incident inclination angle (typically larger than the critical angle), it is possible to make the forward diffracted zero-order vanescent and only the -1st diffracted order to be vertically (in the z-axis direction) out-coupled into air by suitable choice of the grating period”時(shí),這個(gè)大于臨界角的入射角光線竟然不會(huì)繼續(xù)在導(dǎo)光板內(nèi)全反射,而是發(fā)生了衍射,這里我覺(jué)得矛盾[了。既然滿足全反射的條件卻不發(fā)生全反射,為什么呢? AgsR-"uh  
    RVP