lens focal length是什么意思

lens focal length是什么意思 How does a focal length change as a convex lens becomes flatter? focal length的意思 instruction manual for direct drive iris fixed focal vari focal lens 一道SAT2的物理题 光学部分的.A convex lens whose focal length is 20cm has an object placed 10cm away from it.The image distance?答案是-20 请问怎么算的呢? C-lens是什么 If using a larger f/ givesa larger depth of field,why would you always use a larger f/?f/=focal length divided by diameterf/ is f numbers printed on the lens mounting on the camera.我问的不是翻译 关于物理中的光学问题中相机原理 英语翻译LENGTH：8.0是什么 focal distan focal view Slide down lens cover to shoot 中文意思是什么? 光纤准直器的C-lens中文称谓是什么 英语翻译The lens focusing system has also been improved over the conventional 2-group inner focus in terms of a shorter MOD and improved resolution at the picture extremities especially over the middle to telephoto focal range. brim length 中文意思是什么 LENS是什么意思 lens convex FOCAL什么牌子镜头 focal spirit one怎么样