Single-package motion gesture sensor for portable applications

Proximity-based motion gesture sensors (MGSs) using IR LEDs have been widely researched for contactless human-machine interfaces. Conventional MGSs have incorporated discrete photodiodes into a receiver, which prevents them from being adopted for portable handheld devices because of their large size and high profile. This paper proposes a proximity-based contactless MGS that embeds photodiodes and a motion detection algorithm into a single package. The area and height of the proposed optical structure including photodiodes and an optical block are reduced by 96.2% and 71.7%, respectively, compared with the most recently developed MGS. Furthermore, the proposed sensor achieves a recognition rate of over 99.5% on average at various speeds of hand movements. A prototype system is implemented and tested for validation.