NEW : ACLU says machines ' detailed images violate privacy , assault dignity . It 's called `` millimeter-wave passenger imaging technology , '' and it produces a more detailed picture than the metal detectors in use now at airports to screen for weapons and explosives.. New machines use radio waves to scan passengers for hidden objects . They 'll be used on passengers selected for secondary screening . Comment:
NEW : ACLU says machines ' detailed images violate privacy , assault dignity . New machines use radio waves to scan passengers for hidden objects . They 'll be used on passengers selected for secondary screening . Comment: