The focusing is effected after the deflection unit via a focusing lens in front of the scanner head.

通过扫描头前方聚焦透镜的反射单元，调焦发生了变化。

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We leave through the steel doors and head up the ten-story elevator, past the retinal scanner, and through glass Chambers with sliding doors that seem like air locks on a spaceship.

我们从那个大铁门离开，乘着电梯从地下十层来到地上，先通过视网膜扫描，然后穿过一个带有滑动玻璃门好像飞船的空气舱一样的玻璃房间。

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Sheep are mildly sedated by a vet and then strapped to a conveyor, with head cushion for comfort, before passing slowly through the scanner.

接受检查的羊首先被注射镇静剂保证其不会影响接下来的工作，然后被捆绑着送上输送带，为了保证头部舒适，还要垫上专门的软垫，最后才被慢慢送入扫描仪中。

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Thinking during tasks shows up in color in cross-sectional images, recorded as the subject lies with his head inside the scanner.

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Now they have something that works like a flatbed document scanner, with a scanning head containing either six or 12 light-emitting diodes, each emitting light of a specific wavelength between 350 nanometres (ultraviolet) and 800 nanometres (infra-red).

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Rather than a big scanner, it involves a cap worn on a person's head.

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