an uncorrected visual acuity of at least 20/40 (6/12) with both eyes open. : z0 Z e$ k1 J9 r1 j
visual aids (glasses or contact lenses) must have vision of 20:20 (6:6) with both eyes open. ! E8 z3 u! a& t- @) T# R
& i7 ]' L6 ]% }
请问上面的意思是什么?相当于国内什么等级的视力?谢谢!