Solar-Powered Arm Band

• Researchers from the University of Tokyo have created a solar-powered arm band that sounds an alarm if the wearer's body temperature gets too high.
• The device consists of a flexible amorphous silicon solar panel, a piezoelectric speaker, a temperature sensor, and a power supply circuit.
• All of these are created using organic components, such as ink jet-printed onto a polymer film. 
• It can be worn either over clothing or directly against the skin.
• When the temperature sensor detects that the patient's body temperature has risen above a given range, the speaker provides an audible alarm. 
• This is the first time that an organic circuit has been used to create sound, and also the first instance of one featuring an organic power supply circuit. 
• The arm band requires no external power supply.
• It's flexible enough that it doesn't cause discomfort to the patient, and it's cheap enough to dispose of after each use, in order to maintain hygiene.