The HSL-101 has a radio frequency sensor that sends out waves over a roughly 5-foot range. It stands by the bedside and starts scanning once you press the "good night" button.
The device detects body movements such as tossing and turning, as well as breathing. Blankets won't affect the sensor.
The HSL-101, which hits the Japanese market in May, analyses the data and gives you the total time you're awake and asleep with corresponding smiley faces (or sad faces) in the results display.
The HSL-001, on the other hand, is a smaller, palm-size device that sits by a user's pillow.
It does the same thing as the 101 but uses an accelerometer instead. The sensor measures the movement of bedclothes to determine if you've nodded off.
The HSL-001 goes on sale in April and can be used with an Android smartphone app that lets you review how well you slept on a weekly and monthly basis.
If you're not already stressed out about getting enough sleep, another gadget doesn't seem like the best solution to stop tossing and turning. Then again, sleep experts say that establishing a routine before going to bed is the best way to improve sleep quality.
Maybe that button could be the door to golden slumbers.