This paper reports on a blood pressure pulse wave measurement device using the arterial tonometry method calibrated by the pulse transit time. The pressure sensor for arterial tonometry method and the optical sensor for pulse transit time were fabricated. The sizes of pressure sensor and optical sensor are 19×19×9 mm3 and 13×25×4 mm3, respectively. The blood pressure was calculated by the pulse transit time measured by the pressure sensor and the optical sensor. The blood pressure was also measured by the pressure sensor using arterial tonometry method, and by the commercially available sphygmomanometer for comparison. The blood pressure calculated by the pulse transit time was similar to the blood pressure measured by the sphygmomanometer. Therefore, it is useful for the blood pressure measured by arterial tonometry method to calibrate by the blood pressure calculated by the pulse transit time.
We have developed a solar powered watch which has hybrid timekeeping system by combining both GPS signal and the long wave radio signal reception capability. We have reduced the GPS power consumption so that the battery has been downsized. We also achieved the hybrid timekeeping system by developing GPS and radio signal reception algorithm, and by high-density packaging design. This hybrid watch will give users more chance to receive the exact time information than before.
Due to the broad expansion of Smartphones and new connectivity technology of “Bluetooth® Smart” from Bluetooth SIG, various types of “Things” around personal area (“My Things”) have been developed with the Internet connectivity and have become very popular. And for the next, all of the “Things” are considered to be “always connected” to Internet & Cloud services, with the innovation of “IoT” (Internet of Things). It is expected to change the whole world with the significant quality of service & convenience, but not only for those, it is also expected to create innovative human communication, experience, and value with “Connected Devices/Watches” with those “IoT” technologies.