求教

<>是个这样的问题,直角棱镜的斜面通过透镜成像在一平面,因为光程差有一定散焦,成象是近似梯形的,想问下,怎样能消除,</P>

加补偿棱镜

补偿的话光路回变的我加个简图,,,,主要是用到棱镜全反射的面<img src="data/attachment/forum/dvbbs/2004-5/2004514171539961.jpg" border="0" onload="if(this.width>screen.width*0.7) {this.resized=true; this.width=screen.width*0.7; this.alt=\'Click here to open new window\nCTRL+Mouse wheel to zoom in/out\';}" onmouseover="if(this.width>screen.width*0.7) {this.resized=true; this.width=screen.width*0.7; this.style.cursor=\'hand\'; this.alt=\'Click here to open new window\nCTRL+Mouse wheel to zoom in/out\';}" onclick="if(!this.resized) {return true;} else {window.open(\'data/attachment/forum/dvbbs/2004-5/2004514171539961.jpg\');}" onmousewheel="return imgzoom(this);" alt="" />