an uncorrected visual acuity of at least 20/40 (6/12) with both eyes open. 7 b3 c+ U9 h a, K9 I4 R9 v
visual aids (glasses or contact lenses) must have vision of 20:20 (6:6) with both eyes open. % b# \6 b A n" t! S# |$ n- {2 @4 {
3 I- [$ R: H7 T% `7 n) f3 W$ o$ \
请问上面的意思是什么?相当于国内什么等级的视力?谢谢!