http://img0.ph.126.net/RxXtXJIAZGrbu59RcKhMNg==/1165869353552916459.gif
http://img0.ph.126.net/PmSYcGQheEQPBzES4NZJYQ==/6608860929353031795.gif
菲涅尔圆孔衍射时,场点到极点的距离减小时,所划分出的半周期带的数目减少
http://img1.ph.126.net/Lknxy2gDR7Bv9iAmgxez-Q==/6619349170770070135.gif
压疮的主要因素