遮光板
light screen
遮光剂
light-screening agent; opacifier
遮光帘
window blind; window shade
遮光器
light chopper
遮光涂料
opaque paint
遮光物
shade
遮光眼罩
eyeshade
遮光罩
lens hood
有效截止频率
effective cut-off frequency
有效频率
effective frequency
语音频率
speech frequency
预定频率
preset frequency
遇险频率
disstress frequency
原频率
primary frequency
原子频率
atomic frequency
圆频率
circular frequency
载波频率
carrier frequency
振荡频率
oscillation frequency
振荡最大频率
maximum frequency of oscillation
振幅对频率失真
amplitude versus frequency distortion