From http://www.engadget....monitor-patent/
Nintendo first announced its intention to develop a sleep monitor as part of its "quality of life" initiative in 2014. Now, thanks to a recently published patent unearthed byNeoGAF forum members, we have an idea of what the system could look like. The gamemaker is apparently planning to build a sensor-laden alarm clock-like gadget that's equipped with a projector. Since the documents are mostly in Japanese, we only have their summaries and the device's illustration to go by