This is an extreme case, generally complete extinction does not occur. 這是一種極限情況,一般說(shuō)來(lái),并不致發(fā)生完全熄火。
We can approach the limiting case of free propagation by allowing the aperture dimensions to increase indefinitely. 讓孔的線(xiàn)度無(wú)限增大,我們就能趨近于自由傳播的極限情況。