"The best nap duration is 15 to 20 minutes," reckons Japanese startup GiraffeNap. "Anything longer than 30 minutes will cause you to fall into a deep sleep, making it hard to wake up, and will interfere with getting a good night's sleep later."

To that end, the company's eponymous product is a napping pod that lets office workers catch shuteye in a vertical position. The thinking is that the desirable "power nap"—that's Stage 2, non-REM sleep—"washes away brain fatigue" and rejuvenates sleepy office workers. Sleeping vertically, the company claims, gets you to this Stage 2, without letting you lapse into workday-disrupting deep sleep.

The GiraffeNap pods contain four points of support for the human body:

These are height-adjustable via a panel.

The air within the pods is purified using membranes and an airflow system.

Two versions are on offer. The entry-level Forest model is wooden and makes generous use of plywood.

The higher-end Spacia unit has a melamine finish and a more futuristic look. And unlike the Forest model, it's soundproof.

Both units come on casters, to make them easy to move, and obviously take up way less space than a dedicated napping room.

Below is a demo video. (It's in Japanese, but you can turn on the English-translated subtitles.)

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