an uncorrected visual acuity of at least 20/40 (6/12) with both eyes open. 1 k. { G, _ P3 @visual aids (glasses or contact lenses) must have vision of 20:20 (6:6) with both eyes open. 7 |) |- ~# z/ l& a0 ]( a! e3 i+ a0 e+ r, P$ ?5 H
请问上面的意思是什么?相当于国内什么等级的视力?谢谢!