各位大大,最近我在看一篇二区的
论文,题目是Grating_micro-dot_patterned_light_guide_plates_for_LED_backlights,Seung Ryong Park,2007。作者在里面提到,团队的
导光板设计理念是通过在导光板上表面刻正弦型
光栅,使得光以衍射-1级主级大出射,如图所示。那么在作者所希望达到的出射情况(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”时,这个大于临界角的入射角
光线竟然不会继续在导光板内全反射,而是发生了
衍射,这里我觉得矛盾[了。既然满足全反射的条件却不发生全反射,为什么呢?
=*>ri n|q$=jE