Ordinary cameras use filters to block any light in the infrared spectrum.

普通相机用滤光片来阻隔红外光谱范围内的任何光线。

youdao

To eliminate this effect, you can place a small piece of opaque material or black foam just long enough to block the direct part of the light from hitting your subject.

为了消除这种效果，可以在闪光灯灯头上加一片不透明材料或黑色塑料泡沫板做的遮光片，以阻挡扩散的光线照射到被摄体。

youdao

On the flipside, amber and red light can be used to block out blue light to help relieve insomnia and overstimulation.

琥珀光和红色光可以被用来阻止蓝光，从而减轻失眠和过度刺激水平。

youdao

In light of threats from the Israelis to block the flotilla of ships, Zehra Ozturk says she and her fellow pro-Palestinian activists from Turkey are not thinking about a blockade.

VOA: standard.2010.05.28

The microtrichia are believed to block stray light from reaching the eyelets in much the same way as matte-surfaced hoods around camera lenses.

BBC: 100-eyed bug surprises scientists

But it also carries a coronagraph to block the light from bright objects so it can see more easily nearby, dimmer targets - such as planets circling their stars.

BBC: Science & Environment

The 2011 storms dumped a torrent of mud and debris into the bay, and that sediment, which can bury grasses and block them from the light they need to grow, is the most likely cause for the 21 percent drop.

WSJ: Chesapeake Bay grasses decline again