请教这里的视力标准如何换算成国内的数值？

nils_li

an uncorrected visual acuity of at least 20/40 (6/12) with both eyes open.
# G% q: I3 r: T/ k; d3 q- avisual aids (glasses or contact lenses) must have vision of 20:20 (6:6) with both eyes open.
6 j; k. F  Q. ?7 i! c/ e8 z: I
1 E5 l! G( [& 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！